diff.c

   1 /*
   2  * Copyright (C) 2005 Junio C Hamano
   3  */
   4 #include "cache.h"
   5 #include "quote.h"
   6 #include "diff.h"
   7 #include "diffcore.h"
   8 #include "delta.h"
   9 #include "xdiff-interface.h"
  10 #include "color.h"
  11
  12 #ifdef NO_FAST_WORKING_DIRECTORY
  13 #define FAST_WORKING_DIRECTORY 0
  14 #else
  15 #define FAST_WORKING_DIRECTORY 1
  16 #endif
  17
  18 static int use_size_cache;
  19
  20 static int diff_detect_rename_default;
  21 static int diff_rename_limit_default = -1;
  22 static int diff_use_color_default;
  23
  24 static char diff_colors[][COLOR_MAXLEN] = {
  25         "\033[m",       /* reset */
  26         "",             /* PLAIN (normal) */
  27         "\033[1m",      /* METAINFO (bold) */
  28         "\033[36m",     /* FRAGINFO (cyan) */
  29         "\033[31m",     /* OLD (red) */
  30         "\033[32m",     /* NEW (green) */
  31         "\033[33m",     /* COMMIT (yellow) */
  32         "\033[41m",     /* WHITESPACE (red background) */
  33 };
  34
  35 static int parse_diff_color_slot(const char *var, int ofs)
  36 {
  37         if (!strcasecmp(var+ofs, "plain"))
  38                 return DIFF_PLAIN;
  39         if (!strcasecmp(var+ofs, "meta"))
  40                 return DIFF_METAINFO;
  41         if (!strcasecmp(var+ofs, "frag"))
  42                 return DIFF_FRAGINFO;
  43         if (!strcasecmp(var+ofs, "old"))
  44                 return DIFF_FILE_OLD;
  45         if (!strcasecmp(var+ofs, "new"))
  46                 return DIFF_FILE_NEW;
  47         if (!strcasecmp(var+ofs, "commit"))
  48                 return DIFF_COMMIT;
  49         if (!strcasecmp(var+ofs, "whitespace"))
  50                 return DIFF_WHITESPACE;
  51         die("bad config variable '%s'", var);
  52 }
  53
  54 /*
  55  * These are to give UI layer defaults.
  56  * The core-level commands such as git-diff-files should
  57  * never be affected by the setting of diff.renames
  58  * the user happens to have in the configuration file.
  59  */
  60 int git_diff_ui_config(const char *var, const char *value)
  61 {
  62         if (!strcmp(var, "diff.renamelimit")) {
  63                 diff_rename_limit_default = git_config_int(var, value);
  64                 return 0;
  65         }
  66         if (!strcmp(var, "diff.color") || !strcmp(var, "color.diff")) {
  67                 diff_use_color_default = git_config_colorbool(var, value);
  68                 return 0;
  69         }
  70         if (!strcmp(var, "diff.renames")) {
  71                 if (!value)
  72                         diff_detect_rename_default = DIFF_DETECT_RENAME;
  73                 else if (!strcasecmp(value, "copies") ||
  74                          !strcasecmp(value, "copy"))
  75                         diff_detect_rename_default = DIFF_DETECT_COPY;
  76                 else if (git_config_bool(var,value))
  77                         diff_detect_rename_default = DIFF_DETECT_RENAME;
  78                 return 0;
  79         }
  80         if (!strncmp(var, "diff.color.", 11) || !strncmp(var, "color.diff.", 11)) {
  81                 int slot = parse_diff_color_slot(var, 11);
  82                 color_parse(value, var, diff_colors[slot]);
  83                 return 0;
  84         }
  85         return git_default_config(var, value);
  86 }
  87
  88 static char *quote_one(const char *str)
  89 {
  90         int needlen;
  91         char *xp;
  92
  93         if (!str)
  94                 return NULL;
  95         needlen = quote_c_style(str, NULL, NULL, 0);
  96         if (!needlen)
  97                 return xstrdup(str);
  98         xp = xmalloc(needlen + 1);
  99         quote_c_style(str, xp, NULL, 0);
 100         return xp;
 101 }
 102
 103 static char *quote_two(const char *one, const char *two)
 104 {
 105         int need_one = quote_c_style(one, NULL, NULL, 1);
 106         int need_two = quote_c_style(two, NULL, NULL, 1);
 107         char *xp;
 108
 109         if (need_one + need_two) {
 110                 if (!need_one) need_one = strlen(one);
 111                 if (!need_two) need_one = strlen(two);
 112
 113                 xp = xmalloc(need_one + need_two + 3);
 114                 xp[0] = '"';
 115                 quote_c_style(one, xp + 1, NULL, 1);
 116                 quote_c_style(two, xp + need_one + 1, NULL, 1);
 117                 strcpy(xp + need_one + need_two + 1, "\"");
 118                 return xp;
 119         }
 120         need_one = strlen(one);
 121         need_two = strlen(two);
 122         xp = xmalloc(need_one + need_two + 1);
 123         strcpy(xp, one);
 124         strcpy(xp + need_one, two);
 125         return xp;
 126 }
 127
 128 static const char *external_diff(void)
 129 {
 130         static const char *external_diff_cmd = NULL;
 131         static int done_preparing = 0;
 132
 133         if (done_preparing)
 134                 return external_diff_cmd;
 135         external_diff_cmd = getenv("GIT_EXTERNAL_DIFF");
 136         done_preparing = 1;
 137         return external_diff_cmd;
 138 }
 139
 140 #define TEMPFILE_PATH_LEN               50
 141
 142 static struct diff_tempfile {
 143         const char *name; /* filename external diff should read from */
 144         char hex[41];
 145         char mode[10];
 146         char tmp_path[TEMPFILE_PATH_LEN];
 147 } diff_temp[2];
 148
 149 static int count_lines(const char *data, int size)
 150 {
 151         int count, ch, completely_empty = 1, nl_just_seen = 0;
 152         count = 0;
 153         while (0 < size--) {
 154                 ch = *data++;
 155                 if (ch == '\n') {
 156                         count++;
 157                         nl_just_seen = 1;
 158                         completely_empty = 0;
 159                 }
 160                 else {
 161                         nl_just_seen = 0;
 162                         completely_empty = 0;
 163                 }
 164         }
 165         if (completely_empty)
 166                 return 0;
 167         if (!nl_just_seen)
 168                 count++; /* no trailing newline */
 169         return count;
 170 }
 171
 172 static void print_line_count(int count)
 173 {
 174         switch (count) {
 175         case 0:
 176                 printf("0,0");
 177                 break;
 178         case 1:
 179                 printf("1");
 180                 break;
 181         default:
 182                 printf("1,%d", count);
 183                 break;
 184         }
 185 }
 186
 187 static void copy_file(int prefix, const char *data, int size)
 188 {
 189         int ch, nl_just_seen = 1;
 190         while (0 < size--) {
 191                 ch = *data++;
 192                 if (nl_just_seen)
 193                         putchar(prefix);
 194                 putchar(ch);
 195                 if (ch == '\n')
 196                         nl_just_seen = 1;
 197                 else
 198                         nl_just_seen = 0;
 199         }
 200         if (!nl_just_seen)
 201                 printf("\n\\ No newline at end of file\n");
 202 }
 203
 204 static void emit_rewrite_diff(const char *name_a,
 205                               const char *name_b,
 206                               struct diff_filespec *one,
 207                               struct diff_filespec *two)
 208 {
 209         int lc_a, lc_b;
 210         diff_populate_filespec(one, 0);
 211         diff_populate_filespec(two, 0);
 212         lc_a = count_lines(one->data, one->size);
 213         lc_b = count_lines(two->data, two->size);
 214         name_a += (*name_a == '/');
 215         name_b += (*name_b == '/');
 216         printf("--- a/%s\n+++ b/%s\n@@ -", name_a, name_b);
 217         print_line_count(lc_a);
 218         printf(" +");
 219         print_line_count(lc_b);
 220         printf(" @@\n");
 221         if (lc_a)
 222                 copy_file('-', one->data, one->size);
 223         if (lc_b)
 224                 copy_file('+', two->data, two->size);
 225 }
 226
 227 static int fill_mmfile(mmfile_t *mf, struct diff_filespec *one)
 228 {
 229         if (!DIFF_FILE_VALID(one)) {
 230                 mf->ptr = (char *)""; /* does not matter */
 231                 mf->size = 0;
 232                 return 0;
 233         }
 234         else if (diff_populate_filespec(one, 0))
 235                 return -1;
 236         mf->ptr = one->data;
 237         mf->size = one->size;
 238         return 0;
 239 }
 240
 241 struct diff_words_buffer {
 242         mmfile_t text;
 243         long alloc;
 244         long current; /* output pointer */
 245         int suppressed_newline;
 246 };
 247
 248 static void diff_words_append(char *line, unsigned long len,
 249                 struct diff_words_buffer *buffer)
 250 {
 251         if (buffer->text.size + len > buffer->alloc) {
 252                 buffer->alloc = (buffer->text.size + len) * 3 / 2;
 253                 buffer->text.ptr = xrealloc(buffer->text.ptr, buffer->alloc);
 254         }
 255         line++;
 256         len--;
 257         memcpy(buffer->text.ptr + buffer->text.size, line, len);
 258         buffer->text.size += len;
 259 }
 260
 261 struct diff_words_data {
 262         struct xdiff_emit_state xm;
 263         struct diff_words_buffer minus, plus;
 264 };
 265
 266 static void print_word(struct diff_words_buffer *buffer, int len, int color,
 267                 int suppress_newline)
 268 {
 269         const char *ptr;
 270         int eol = 0;
 271
 272         if (len == 0)
 273                 return;
 274
 275         ptr  = buffer->text.ptr + buffer->current;
 276         buffer->current += len;
 277
 278         if (ptr[len - 1] == '\n') {
 279                 eol = 1;
 280                 len--;
 281         }
 282
 283         fputs(diff_get_color(1, color), stdout);
 284         fwrite(ptr, len, 1, stdout);
 285         fputs(diff_get_color(1, DIFF_RESET), stdout);
 286
 287         if (eol) {
 288                 if (suppress_newline)
 289                         buffer->suppressed_newline = 1;
 290                 else
 291                         putchar('\n');
 292         }
 293 }
 294
 295 static void fn_out_diff_words_aux(void *priv, char *line, unsigned long len)
 296 {
 297         struct diff_words_data *diff_words = priv;
 298
 299         if (diff_words->minus.suppressed_newline) {
 300                 if (line[0] != '+')
 301                         putchar('\n');
 302                 diff_words->minus.suppressed_newline = 0;
 303         }
 304
 305         len--;
 306         switch (line[0]) {
 307                 case '-':
 308                         print_word(&diff_words->minus, len, DIFF_FILE_OLD, 1);
 309                         break;
 310                 case '+':
 311                         print_word(&diff_words->plus, len, DIFF_FILE_NEW, 0);
 312                         break;
 313                 case ' ':
 314                         print_word(&diff_words->plus, len, DIFF_PLAIN, 0);
 315                         diff_words->minus.current += len;
 316                         break;
 317         }
 318 }
 319
 320 /* this executes the word diff on the accumulated buffers */
 321 static void diff_words_show(struct diff_words_data *diff_words)
 322 {
 323         xpparam_t xpp;
 324         xdemitconf_t xecfg;
 325         xdemitcb_t ecb;
 326         mmfile_t minus, plus;
 327         int i;
 328
 329         minus.size = diff_words->minus.text.size;
 330         minus.ptr = xmalloc(minus.size);
 331         memcpy(minus.ptr, diff_words->minus.text.ptr, minus.size);
 332         for (i = 0; i < minus.size; i++)
 333                 if (isspace(minus.ptr[i]))
 334                         minus.ptr[i] = '\n';
 335         diff_words->minus.current = 0;
 336
 337         plus.size = diff_words->plus.text.size;
 338         plus.ptr = xmalloc(plus.size);
 339         memcpy(plus.ptr, diff_words->plus.text.ptr, plus.size);
 340         for (i = 0; i < plus.size; i++)
 341                 if (isspace(plus.ptr[i]))
 342                         plus.ptr[i] = '\n';
 343         diff_words->plus.current = 0;
 344
 345         xpp.flags = XDF_NEED_MINIMAL;
 346         xecfg.ctxlen = diff_words->minus.alloc + diff_words->plus.alloc;
 347         xecfg.flags = 0;
 348         ecb.outf = xdiff_outf;
 349         ecb.priv = diff_words;
 350         diff_words->xm.consume = fn_out_diff_words_aux;
 351         xdl_diff(&minus, &plus, &xpp, &xecfg, &ecb);
 352
 353         free(minus.ptr);
 354         free(plus.ptr);
 355         diff_words->minus.text.size = diff_words->plus.text.size = 0;
 356
 357         if (diff_words->minus.suppressed_newline) {
 358                 putchar('\n');
 359                 diff_words->minus.suppressed_newline = 0;
 360         }
 361 }
 362
 363 struct emit_callback {
 364         struct xdiff_emit_state xm;
 365         int nparents, color_diff;
 366         const char **label_path;
 367         struct diff_words_data *diff_words;
 368 };
 369
 370 static void free_diff_words_data(struct emit_callback *ecbdata)
 371 {
 372         if (ecbdata->diff_words) {
 373                 /* flush buffers */
 374                 if (ecbdata->diff_words->minus.text.size ||
 375                                 ecbdata->diff_words->plus.text.size)
 376                         diff_words_show(ecbdata->diff_words);
 377
 378                 if (ecbdata->diff_words->minus.text.ptr)
 379                         free (ecbdata->diff_words->minus.text.ptr);
 380                 if (ecbdata->diff_words->plus.text.ptr)
 381                         free (ecbdata->diff_words->plus.text.ptr);
 382                 free(ecbdata->diff_words);
 383                 ecbdata->diff_words = NULL;
 384         }
 385 }
 386
 387 const char *diff_get_color(int diff_use_color, enum color_diff ix)
 388 {
 389         if (diff_use_color)
 390                 return diff_colors[ix];
 391         return "";
 392 }
 393
 394 static void emit_line(const char *set, const char *reset, const char *line, int len)
 395 {
 396         if (len > 0 && line[len-1] == '\n')
 397                 len--;
 398         fputs(set, stdout);
 399         fwrite(line, len, 1, stdout);
 400         puts(reset);
 401 }
 402
 403 static void emit_add_line(const char *reset, struct emit_callback *ecbdata, const char *line, int len)
 404 {
 405         int col0 = ecbdata->nparents;
 406         int last_tab_in_indent = -1;
 407         int last_space_in_indent = -1;
 408         int i;
 409         int tail = len;
 410         int need_highlight_leading_space = 0;
 411         const char *ws = diff_get_color(ecbdata->color_diff, DIFF_WHITESPACE);
 412         const char *set = diff_get_color(ecbdata->color_diff, DIFF_FILE_NEW);
 413
 414         if (!*ws) {
 415                 emit_line(set, reset, line, len);
 416                 return;
 417         }
 418
 419         /* The line is a newly added line.  Does it have funny leading
 420          * whitespaces?  In indent, SP should never precede a TAB.
 421          */
 422         for (i = col0; i < len; i++) {
 423                 if (line[i] == '\t') {
 424                         last_tab_in_indent = i;
 425                         if (0 <= last_space_in_indent)
 426                                 need_highlight_leading_space = 1;
 427                 }
 428                 else if (line[i] == ' ')
 429                         last_space_in_indent = i;
 430                 else
 431                         break;
 432         }
 433         fputs(set, stdout);
 434         fwrite(line, col0, 1, stdout);
 435         fputs(reset, stdout);
 436         if (((i == len) || line[i] == '\n') && i != col0) {
 437                 /* The whole line was indent */
 438                 emit_line(ws, reset, line + col0, len - col0);
 439                 return;
 440         }
 441         i = col0;
 442         if (need_highlight_leading_space) {
 443                 while (i < last_tab_in_indent) {
 444                         if (line[i] == ' ') {
 445                                 fputs(ws, stdout);
 446                                 putchar(' ');
 447                                 fputs(reset, stdout);
 448                         }
 449                         else
 450                                 putchar(line[i]);
 451                         i++;
 452                 }
 453         }
 454         tail = len - 1;
 455         if (line[tail] == '\n' && i < tail)
 456                 tail--;
 457         while (i < tail) {
 458                 if (!isspace(line[tail]))
 459                         break;
 460                 tail--;
 461         }
 462         if ((i < tail && line[tail + 1] != '\n')) {
 463                 /* This has whitespace between tail+1..len */
 464                 fputs(set, stdout);
 465                 fwrite(line + i, tail - i + 1, 1, stdout);
 466                 fputs(reset, stdout);
 467                 emit_line(ws, reset, line + tail + 1, len - tail - 1);
 468         }
 469         else
 470                 emit_line(set, reset, line + i, len - i);
 471 }
 472
 473 static void fn_out_consume(void *priv, char *line, unsigned long len)
 474 {
 475         int i;
 476         int color;
 477         struct emit_callback *ecbdata = priv;
 478         const char *set = diff_get_color(ecbdata->color_diff, DIFF_METAINFO);
 479         const char *reset = diff_get_color(ecbdata->color_diff, DIFF_RESET);
 480
 481         if (ecbdata->label_path[0]) {
 482                 printf("%s--- %s%s\n", set, ecbdata->label_path[0], reset);
 483                 printf("%s+++ %s%s\n", set, ecbdata->label_path[1], reset);
 484                 ecbdata->label_path[0] = ecbdata->label_path[1] = NULL;
 485         }
 486
 487         /* This is not really necessary for now because
 488          * this codepath only deals with two-way diffs.
 489          */
 490         for (i = 0; i < len && line[i] == '@'; i++)
 491                 ;
 492         if (2 <= i && i < len && line[i] == ' ') {
 493                 ecbdata->nparents = i - 1;
 494                 emit_line(diff_get_color(ecbdata->color_diff, DIFF_FRAGINFO),
 495                           reset, line, len);
 496                 return;
 497         }
 498
 499         if (len < ecbdata->nparents) {
 500                 set = reset;
 501                 emit_line(reset, reset, line, len);
 502                 return;
 503         }
 504
 505         color = DIFF_PLAIN;
 506         if (ecbdata->diff_words && ecbdata->nparents != 1)
 507                 /* fall back to normal diff */
 508                 free_diff_words_data(ecbdata);
 509         if (ecbdata->diff_words) {
 510                 if (line[0] == '-') {
 511                         diff_words_append(line, len,
 512                                           &ecbdata->diff_words->minus);
 513                         return;
 514                 } else if (line[0] == '+') {
 515                         diff_words_append(line, len,
 516                                           &ecbdata->diff_words->plus);
 517                         return;
 518                 }
 519                 if (ecbdata->diff_words->minus.text.size ||
 520                     ecbdata->diff_words->plus.text.size)
 521                         diff_words_show(ecbdata->diff_words);
 522                 line++;
 523                 len--;
 524                 emit_line(set, reset, line, len);
 525                 return;
 526         }
 527         for (i = 0; i < ecbdata->nparents && len; i++) {
 528                 if (line[i] == '-')
 529                         color = DIFF_FILE_OLD;
 530                 else if (line[i] == '+')
 531                         color = DIFF_FILE_NEW;
 532         }
 533
 534         if (color != DIFF_FILE_NEW) {
 535                 emit_line(diff_get_color(ecbdata->color_diff, color),
 536                           reset, line, len);
 537                 return;
 538         }
 539         emit_add_line(reset, ecbdata, line, len);
 540 }
 541
 542 static char *pprint_rename(const char *a, const char *b)
 543 {
 544         const char *old = a;
 545         const char *new = b;
 546         char *name = NULL;
 547         int pfx_length, sfx_length;
 548         int len_a = strlen(a);
 549         int len_b = strlen(b);
 550         int qlen_a = quote_c_style(a, NULL, NULL, 0);
 551         int qlen_b = quote_c_style(b, NULL, NULL, 0);
 552
 553         if (qlen_a || qlen_b) {
 554                 if (qlen_a) len_a = qlen_a;
 555                 if (qlen_b) len_b = qlen_b;
 556                 name = xmalloc( len_a + len_b + 5 );
 557                 if (qlen_a)
 558                         quote_c_style(a, name, NULL, 0);
 559                 else
 560                         memcpy(name, a, len_a);
 561                 memcpy(name + len_a, " => ", 4);
 562                 if (qlen_b)
 563                         quote_c_style(b, name + len_a + 4, NULL, 0);
 564                 else
 565                         memcpy(name + len_a + 4, b, len_b + 1);
 566                 return name;
 567         }
 568
 569         /* Find common prefix */
 570         pfx_length = 0;
 571         while (*old && *new && *old == *new) {
 572                 if (*old == '/')
 573                         pfx_length = old - a + 1;
 574                 old++;
 575                 new++;
 576         }
 577
 578         /* Find common suffix */
 579         old = a + len_a;
 580         new = b + len_b;
 581         sfx_length = 0;
 582         while (a <= old && b <= new && *old == *new) {
 583                 if (*old == '/')
 584                         sfx_length = len_a - (old - a);
 585                 old--;
 586                 new--;
 587         }
 588
 589         /*
 590          * pfx{mid-a => mid-b}sfx
 591          * {pfx-a => pfx-b}sfx
 592          * pfx{sfx-a => sfx-b}
 593          * name-a => name-b
 594          */
 595         if (pfx_length + sfx_length) {
 596                 int a_midlen = len_a - pfx_length - sfx_length;
 597                 int b_midlen = len_b - pfx_length - sfx_length;
 598                 if (a_midlen < 0) a_midlen = 0;
 599                 if (b_midlen < 0) b_midlen = 0;
 600
 601                 name = xmalloc(pfx_length + a_midlen + b_midlen + sfx_length + 7);
 602                 sprintf(name, "%.*s{%.*s => %.*s}%s",
 603                         pfx_length, a,
 604                         a_midlen, a + pfx_length,
 605                         b_midlen, b + pfx_length,
 606                         a + len_a - sfx_length);
 607         }
 608         else {
 609                 name = xmalloc(len_a + len_b + 5);
 610                 sprintf(name, "%s => %s", a, b);
 611         }
 612         return name;
 613 }
 614
 615 struct diffstat_t {
 616         struct xdiff_emit_state xm;
 617
 618         int nr;
 619         int alloc;
 620         struct diffstat_file {
 621                 char *name;
 622                 unsigned is_unmerged:1;
 623                 unsigned is_binary:1;
 624                 unsigned is_renamed:1;
 625                 unsigned int added, deleted;
 626         } **files;
 627 };
 628
 629 static struct diffstat_file *diffstat_add(struct diffstat_t *diffstat,
 630                                           const char *name_a,
 631                                           const char *name_b)
 632 {
 633         struct diffstat_file *x;
 634         x = xcalloc(sizeof (*x), 1);
 635         if (diffstat->nr == diffstat->alloc) {
 636                 diffstat->alloc = alloc_nr(diffstat->alloc);
 637                 diffstat->files = xrealloc(diffstat->files,
 638                                 diffstat->alloc * sizeof(x));
 639         }
 640         diffstat->files[diffstat->nr++] = x;
 641         if (name_b) {
 642                 x->name = pprint_rename(name_a, name_b);
 643                 x->is_renamed = 1;
 644         }
 645         else
 646                 x->name = xstrdup(name_a);
 647         return x;
 648 }
 649
 650 static void diffstat_consume(void *priv, char *line, unsigned long len)
 651 {
 652         struct diffstat_t *diffstat = priv;
 653         struct diffstat_file *x = diffstat->files[diffstat->nr - 1];
 654
 655         if (line[0] == '+')
 656                 x->added++;
 657         else if (line[0] == '-')
 658                 x->deleted++;
 659 }
 660
 661 const char mime_boundary_leader[] = "------------";
 662
 663 static int scale_linear(int it, int width, int max_change)
 664 {
 665         /*
 666          * make sure that at least one '-' is printed if there were deletions,
 667          * and likewise for '+'.
 668          */
 669         if (max_change < 2)
 670                 return it;
 671         return ((it - 1) * (width - 1) + max_change - 1) / (max_change - 1);
 672 }
 673
 674 static void show_name(const char *prefix, const char *name, int len,
 675                       const char *reset, const char *set)
 676 {
 677         printf(" %s%s%-*s%s |", set, prefix, len, name, reset);
 678 }
 679
 680 static void show_graph(char ch, int cnt, const char *set, const char *reset)
 681 {
 682         if (cnt <= 0)
 683                 return;
 684         printf("%s", set);
 685         while (cnt--)
 686                 putchar(ch);
 687         printf("%s", reset);
 688 }
 689
 690 static void show_stats(struct diffstat_t* data, struct diff_options *options)
 691 {
 692         int i, len, add, del, total, adds = 0, dels = 0;
 693         int max_change = 0, max_len = 0;
 694         int total_files = data->nr;
 695         int width, name_width;
 696         const char *reset, *set, *add_c, *del_c;
 697
 698         if (data->nr == 0)
 699                 return;
 700
 701         width = options->stat_width ? options->stat_width : 80;
 702         name_width = options->stat_name_width ? options->stat_name_width : 50;
 703
 704         /* Sanity: give at least 5 columns to the graph,
 705          * but leave at least 10 columns for the name.
 706          */
 707         if (width < name_width + 15) {
 708                 if (name_width <= 25)
 709                         width = name_width + 15;
 710                 else
 711                         name_width = width - 15;
 712         }
 713
 714         /* Find the longest filename and max number of changes */
 715         reset = diff_get_color(options->color_diff, DIFF_RESET);
 716         set = diff_get_color(options->color_diff, DIFF_PLAIN);
 717         add_c = diff_get_color(options->color_diff, DIFF_FILE_NEW);
 718         del_c = diff_get_color(options->color_diff, DIFF_FILE_OLD);
 719
 720         for (i = 0; i < data->nr; i++) {
 721                 struct diffstat_file *file = data->files[i];
 722                 int change = file->added + file->deleted;
 723
 724                 if (!file->is_renamed) {  /* renames are already quoted by pprint_rename */
 725                         len = quote_c_style(file->name, NULL, NULL, 0);
 726                         if (len) {
 727                                 char *qname = xmalloc(len + 1);
 728                                 quote_c_style(file->name, qname, NULL, 0);
 729                                 free(file->name);
 730                                 file->name = qname;
 731                         }
 732                 }
 733
 734                 len = strlen(file->name);
 735                 if (max_len < len)
 736                         max_len = len;
 737
 738                 if (file->is_binary || file->is_unmerged)
 739                         continue;
 740                 if (max_change < change)
 741                         max_change = change;
 742         }
 743
 744         /* Compute the width of the graph part;
 745          * 10 is for one blank at the beginning of the line plus
 746          * " | count " between the name and the graph.
 747          *
 748          * From here on, name_width is the width of the name area,
 749          * and width is the width of the graph area.
 750          */
 751         name_width = (name_width < max_len) ? name_width : max_len;
 752         if (width < (name_width + 10) + max_change)
 753                 width = width - (name_width + 10);
 754         else
 755                 width = max_change;
 756
 757         for (i = 0; i < data->nr; i++) {
 758                 const char *prefix = "";
 759                 char *name = data->files[i]->name;
 760                 int added = data->files[i]->added;
 761                 int deleted = data->files[i]->deleted;
 762                 int name_len;
 763
 764                 /*
 765                  * "scale" the filename
 766                  */
 767                 len = name_width;
 768                 name_len = strlen(name);
 769                 if (name_width < name_len) {
 770                         char *slash;
 771                         prefix = "...";
 772                         len -= 3;
 773                         name += name_len - len;
 774                         slash = strchr(name, '/');
 775                         if (slash)
 776                                 name = slash;
 777                 }
 778
 779                 if (data->files[i]->is_binary) {
 780                         show_name(prefix, name, len, reset, set);
 781                         printf("  Bin\n");
 782                         goto free_diffstat_file;
 783                 }
 784                 else if (data->files[i]->is_unmerged) {
 785                         show_name(prefix, name, len, reset, set);
 786                         printf("  Unmerged\n");
 787                         goto free_diffstat_file;
 788                 }
 789                 else if (!data->files[i]->is_renamed &&
 790                          (added + deleted == 0)) {
 791                         total_files--;
 792                         goto free_diffstat_file;
 793                 }
 794
 795                 /*
 796                  * scale the add/delete
 797                  */
 798                 add = added;
 799                 del = deleted;
 800                 total = add + del;
 801                 adds += add;
 802                 dels += del;
 803
 804                 if (width <= max_change) {
 805                         add = scale_linear(add, width, max_change);
 806                         del = scale_linear(del, width, max_change);
 807                         total = add + del;
 808                 }
 809                 show_name(prefix, name, len, reset, set);
 810                 printf("%5d ", added + deleted);
 811                 show_graph('+', add, add_c, reset);
 812                 show_graph('-', del, del_c, reset);
 813                 putchar('\n');
 814         free_diffstat_file:
 815                 free(data->files[i]->name);
 816                 free(data->files[i]);
 817         }
 818         free(data->files);
 819         printf("%s %d files changed, %d insertions(+), %d deletions(-)%s\n",
 820                set, total_files, adds, dels, reset);
 821 }
 822
 823 static void show_shortstats(struct diffstat_t* data)
 824 {
 825         int i, adds = 0, dels = 0, total_files = data->nr;
 826
 827         if (data->nr == 0)
 828                 return;
 829
 830         for (i = 0; i < data->nr; i++) {
 831                 if (!data->files[i]->is_binary &&
 832                     !data->files[i]->is_unmerged) {
 833                         int added = data->files[i]->added;
 834                         int deleted= data->files[i]->deleted;
 835                         if (!data->files[i]->is_renamed &&
 836                             (added + deleted == 0)) {
 837                                 total_files--;
 838                         } else {
 839                                 adds += added;
 840                                 dels += deleted;
 841                         }
 842                 }
 843                 free(data->files[i]->name);
 844                 free(data->files[i]);
 845         }
 846         free(data->files);
 847
 848         printf(" %d files changed, %d insertions(+), %d deletions(-)\n",
 849                total_files, adds, dels);
 850 }
 851
 852 static void show_numstat(struct diffstat_t* data, struct diff_options *options)
 853 {
 854         int i;
 855
 856         for (i = 0; i < data->nr; i++) {
 857                 struct diffstat_file *file = data->files[i];
 858
 859                 if (file->is_binary)
 860                         printf("-\t-\t");
 861                 else
 862                         printf("%d\t%d\t", file->added, file->deleted);
 863                 if (options->line_termination && !file->is_renamed &&
 864                     quote_c_style(file->name, NULL, NULL, 0))
 865                         quote_c_style(file->name, NULL, stdout, 0);
 866                 else
 867                         fputs(file->name, stdout);
 868                 putchar(options->line_termination);
 869         }
 870 }
 871
 872 struct checkdiff_t {
 873         struct xdiff_emit_state xm;
 874         const char *filename;
 875         int lineno;
 876 };
 877
 878 static void checkdiff_consume(void *priv, char *line, unsigned long len)
 879 {
 880         struct checkdiff_t *data = priv;
 881
 882         if (line[0] == '+') {
 883                 int i, spaces = 0;
 884
 885                 /* check space before tab */
 886                 for (i = 1; i < len && (line[i] == ' ' || line[i] == '\t'); i++)
 887                         if (line[i] == ' ')
 888                                 spaces++;
 889                 if (line[i - 1] == '\t' && spaces)
 890                         printf("%s:%d: space before tab:%.*s\n",
 891                                 data->filename, data->lineno, (int)len, line);
 892
 893                 /* check white space at line end */
 894                 if (line[len - 1] == '\n')
 895                         len--;
 896                 if (isspace(line[len - 1]))
 897                         printf("%s:%d: white space at end: %.*s\n",
 898                                 data->filename, data->lineno, (int)len, line);
 899
 900                 data->lineno++;
 901         } else if (line[0] == ' ')
 902                 data->lineno++;
 903         else if (line[0] == '@') {
 904                 char *plus = strchr(line, '+');
 905                 if (plus)
 906                         data->lineno = strtol(plus, NULL, 10);
 907                 else
 908                         die("invalid diff");
 909         }
 910 }
 911
 912 static unsigned char *deflate_it(char *data,
 913                                  unsigned long size,
 914                                  unsigned long *result_size)
 915 {
 916         int bound;
 917         unsigned char *deflated;
 918         z_stream stream;
 919
 920         memset(&stream, 0, sizeof(stream));
 921         deflateInit(&stream, zlib_compression_level);
 922         bound = deflateBound(&stream, size);
 923         deflated = xmalloc(bound);
 924         stream.next_out = deflated;
 925         stream.avail_out = bound;
 926
 927         stream.next_in = (unsigned char *)data;
 928         stream.avail_in = size;
 929         while (deflate(&stream, Z_FINISH) == Z_OK)
 930                 ; /* nothing */
 931         deflateEnd(&stream);
 932         *result_size = stream.total_out;
 933         return deflated;
 934 }
 935
 936 static void emit_binary_diff_body(mmfile_t *one, mmfile_t *two)
 937 {
 938         void *cp;
 939         void *delta;
 940         void *deflated;
 941         void *data;
 942         unsigned long orig_size;
 943         unsigned long delta_size;
 944         unsigned long deflate_size;
 945         unsigned long data_size;
 946
 947         /* We could do deflated delta, or we could do just deflated two,
 948          * whichever is smaller.
 949          */
 950         delta = NULL;
 951         deflated = deflate_it(two->ptr, two->size, &deflate_size);
 952         if (one->size && two->size) {
 953                 delta = diff_delta(one->ptr, one->size,
 954                                    two->ptr, two->size,
 955                                    &delta_size, deflate_size);
 956                 if (delta) {
 957                         void *to_free = delta;
 958                         orig_size = delta_size;
 959                         delta = deflate_it(delta, delta_size, &delta_size);
 960                         free(to_free);
 961                 }
 962         }
 963
 964         if (delta && delta_size < deflate_size) {
 965                 printf("delta %lu\n", orig_size);
 966                 free(deflated);
 967                 data = delta;
 968                 data_size = delta_size;
 969         }
 970         else {
 971                 printf("literal %lu\n", two->size);
 972                 free(delta);
 973                 data = deflated;
 974                 data_size = deflate_size;
 975         }
 976
 977         /* emit data encoded in base85 */
 978         cp = data;
 979         while (data_size) {
 980                 int bytes = (52 < data_size) ? 52 : data_size;
 981                 char line[70];
 982                 data_size -= bytes;
 983                 if (bytes <= 26)
 984                         line[0] = bytes + 'A' - 1;
 985                 else
 986                         line[0] = bytes - 26 + 'a' - 1;
 987                 encode_85(line + 1, cp, bytes);
 988                 cp = (char *) cp + bytes;
 989                 puts(line);
 990         }
 991         printf("\n");
 992         free(data);
 993 }
 994
 995 static void emit_binary_diff(mmfile_t *one, mmfile_t *two)
 996 {
 997         printf("GIT binary patch\n");
 998         emit_binary_diff_body(one, two);
 999         emit_binary_diff_body(two, one);
1000 }
1001
1002 #define FIRST_FEW_BYTES 8000
1003 static int mmfile_is_binary(mmfile_t *mf)
1004 {
1005         long sz = mf->size;
1006         if (FIRST_FEW_BYTES < sz)
1007                 sz = FIRST_FEW_BYTES;
1008         return !!memchr(mf->ptr, 0, sz);
1009 }
1010
1011 static void builtin_diff(const char *name_a,
1012                          const char *name_b,
1013                          struct diff_filespec *one,
1014                          struct diff_filespec *two,
1015                          const char *xfrm_msg,
1016                          struct diff_options *o,
1017                          int complete_rewrite)
1018 {
1019         mmfile_t mf1, mf2;
1020         const char *lbl[2];
1021         char *a_one, *b_two;
1022         const char *set = diff_get_color(o->color_diff, DIFF_METAINFO);
1023         const char *reset = diff_get_color(o->color_diff, DIFF_RESET);
1024
1025         a_one = quote_two("a/", name_a + (*name_a == '/'));
1026         b_two = quote_two("b/", name_b + (*name_b == '/'));
1027         lbl[0] = DIFF_FILE_VALID(one) ? a_one : "/dev/null";
1028         lbl[1] = DIFF_FILE_VALID(two) ? b_two : "/dev/null";
1029         printf("%sdiff --git %s %s%s\n", set, a_one, b_two, reset);
1030         if (lbl[0][0] == '/') {
1031                 /* /dev/null */
1032                 printf("%snew file mode %06o%s\n", set, two->mode, reset);
1033                 if (xfrm_msg && xfrm_msg[0])
1034                         printf("%s%s%s\n", set, xfrm_msg, reset);
1035         }
1036         else if (lbl[1][0] == '/') {
1037                 printf("%sdeleted file mode %06o%s\n", set, one->mode, reset);
1038                 if (xfrm_msg && xfrm_msg[0])
1039                         printf("%s%s%s\n", set, xfrm_msg, reset);
1040         }
1041         else {
1042                 if (one->mode != two->mode) {
1043                         printf("%sold mode %06o%s\n", set, one->mode, reset);
1044                         printf("%snew mode %06o%s\n", set, two->mode, reset);
1045                 }
1046                 if (xfrm_msg && xfrm_msg[0])
1047                         printf("%s%s%s\n", set, xfrm_msg, reset);
1048                 /*
1049                  * we do not run diff between different kind
1050                  * of objects.
1051                  */
1052                 if ((one->mode ^ two->mode) & S_IFMT)
1053                         goto free_ab_and_return;
1054                 if (complete_rewrite) {
1055                         emit_rewrite_diff(name_a, name_b, one, two);
1056                         goto free_ab_and_return;
1057                 }
1058         }
1059
1060         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
1061                 die("unable to read files to diff");
1062
1063         if (!o->text && (mmfile_is_binary(&mf1) || mmfile_is_binary(&mf2))) {
1064                 /* Quite common confusing case */
1065                 if (mf1.size == mf2.size &&
1066                     !memcmp(mf1.ptr, mf2.ptr, mf1.size))
1067                         goto free_ab_and_return;
1068                 if (o->binary)
1069                         emit_binary_diff(&mf1, &mf2);
1070                 else
1071                         printf("Binary files %s and %s differ\n",
1072                                lbl[0], lbl[1]);
1073         }
1074         else {
1075                 /* Crazy xdl interfaces.. */
1076                 const char *diffopts = getenv("GIT_DIFF_OPTS");
1077                 xpparam_t xpp;
1078                 xdemitconf_t xecfg;
1079                 xdemitcb_t ecb;
1080                 struct emit_callback ecbdata;
1081
1082                 memset(&ecbdata, 0, sizeof(ecbdata));
1083                 ecbdata.label_path = lbl;
1084                 ecbdata.color_diff = o->color_diff;
1085                 xpp.flags = XDF_NEED_MINIMAL | o->xdl_opts;
1086                 xecfg.ctxlen = o->context;
1087                 xecfg.flags = XDL_EMIT_FUNCNAMES;
1088                 if (!diffopts)
1089                         ;
1090                 else if (!strncmp(diffopts, "--unified=", 10))
1091                         xecfg.ctxlen = strtoul(diffopts + 10, NULL, 10);
1092                 else if (!strncmp(diffopts, "-u", 2))
1093                         xecfg.ctxlen = strtoul(diffopts + 2, NULL, 10);
1094                 ecb.outf = xdiff_outf;
1095                 ecb.priv = &ecbdata;
1096                 ecbdata.xm.consume = fn_out_consume;
1097                 if (o->color_diff_words)
1098                         ecbdata.diff_words =
1099                                 xcalloc(1, sizeof(struct diff_words_data));
1100                 xdl_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
1101                 if (o->color_diff_words)
1102                         free_diff_words_data(&ecbdata);
1103         }
1104
1105  free_ab_and_return:
1106         free(a_one);
1107         free(b_two);
1108         return;
1109 }
1110
1111 static void builtin_diffstat(const char *name_a, const char *name_b,
1112                              struct diff_filespec *one,
1113                              struct diff_filespec *two,
1114                              struct diffstat_t *diffstat,
1115                              struct diff_options *o,
1116                              int complete_rewrite)
1117 {
1118         mmfile_t mf1, mf2;
1119         struct diffstat_file *data;
1120
1121         data = diffstat_add(diffstat, name_a, name_b);
1122
1123         if (!one || !two) {
1124                 data->is_unmerged = 1;
1125                 return;
1126         }
1127         if (complete_rewrite) {
1128                 diff_populate_filespec(one, 0);
1129                 diff_populate_filespec(two, 0);
1130                 data->deleted = count_lines(one->data, one->size);
1131                 data->added = count_lines(two->data, two->size);
1132                 return;
1133         }
1134         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
1135                 die("unable to read files to diff");
1136
1137         if (mmfile_is_binary(&mf1) || mmfile_is_binary(&mf2))
1138                 data->is_binary = 1;
1139         else {
1140                 /* Crazy xdl interfaces.. */
1141                 xpparam_t xpp;
1142                 xdemitconf_t xecfg;
1143                 xdemitcb_t ecb;
1144
1145                 xpp.flags = XDF_NEED_MINIMAL | o->xdl_opts;
1146                 xecfg.ctxlen = 0;
1147                 xecfg.flags = 0;
1148                 ecb.outf = xdiff_outf;
1149                 ecb.priv = diffstat;
1150                 xdl_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
1151         }
1152 }
1153
1154 static void builtin_checkdiff(const char *name_a, const char *name_b,
1155                              struct diff_filespec *one,
1156                              struct diff_filespec *two)
1157 {
1158         mmfile_t mf1, mf2;
1159         struct checkdiff_t data;
1160
1161         if (!two)
1162                 return;
1163
1164         memset(&data, 0, sizeof(data));
1165         data.xm.consume = checkdiff_consume;
1166         data.filename = name_b ? name_b : name_a;
1167         data.lineno = 0;
1168
1169         if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
1170                 die("unable to read files to diff");
1171
1172         if (mmfile_is_binary(&mf2))
1173                 return;
1174         else {
1175                 /* Crazy xdl interfaces.. */
1176                 xpparam_t xpp;
1177                 xdemitconf_t xecfg;
1178                 xdemitcb_t ecb;
1179
1180                 xpp.flags = XDF_NEED_MINIMAL;
1181                 xecfg.ctxlen = 0;
1182                 xecfg.flags = 0;
1183                 ecb.outf = xdiff_outf;
1184                 ecb.priv = &data;
1185                 xdl_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
1186         }
1187 }
1188
1189 struct diff_filespec *alloc_filespec(const char *path)
1190 {
1191         int namelen = strlen(path);
1192         struct diff_filespec *spec = xmalloc(sizeof(*spec) + namelen + 1);
1193
1194         memset(spec, 0, sizeof(*spec));
1195         spec->path = (char *)(spec + 1);
1196         memcpy(spec->path, path, namelen+1);
1197         return spec;
1198 }
1199
1200 void fill_filespec(struct diff_filespec *spec, const unsigned char *sha1,
1201                    unsigned short mode)
1202 {
1203         if (mode) {
1204                 spec->mode = canon_mode(mode);
1205                 hashcpy(spec->sha1, sha1);
1206                 spec->sha1_valid = !is_null_sha1(sha1);
1207         }
1208 }
1209
1210 /*
1211  * Given a name and sha1 pair, if the dircache tells us the file in
1212  * the work tree has that object contents, return true, so that
1213  * prepare_temp_file() does not have to inflate and extract.
1214  */
1215 static int reuse_worktree_file(const char *name, const unsigned char *sha1, int want_file)
1216 {
1217         struct cache_entry *ce;
1218         struct stat st;
1219         int pos, len;
1220
1221         /* We do not read the cache ourselves here, because the
1222          * benchmark with my previous version that always reads cache
1223          * shows that it makes things worse for diff-tree comparing
1224          * two linux-2.6 kernel trees in an already checked out work
1225          * tree.  This is because most diff-tree comparisons deal with
1226          * only a small number of files, while reading the cache is
1227          * expensive for a large project, and its cost outweighs the
1228          * savings we get by not inflating the object to a temporary
1229          * file.  Practically, this code only helps when we are used
1230          * by diff-cache --cached, which does read the cache before
1231          * calling us.
1232          */
1233         if (!active_cache)
1234                 return 0;
1235
1236         /* We want to avoid the working directory if our caller
1237          * doesn't need the data in a normal file, this system
1238          * is rather slow with its stat/open/mmap/close syscalls,
1239          * and the object is contained in a pack file.  The pack
1240          * is probably already open and will be faster to obtain
1241          * the data through than the working directory.  Loose
1242          * objects however would tend to be slower as they need
1243          * to be individually opened and inflated.
1244          */
1245         if (!FAST_WORKING_DIRECTORY && !want_file && has_sha1_pack(sha1, NULL))
1246                 return 0;
1247
1248         len = strlen(name);
1249         pos = cache_name_pos(name, len);
1250         if (pos < 0)
1251                 return 0;
1252         ce = active_cache[pos];
1253         if ((lstat(name, &st) < 0) ||
1254             !S_ISREG(st.st_mode) || /* careful! */
1255             ce_match_stat(ce, &st, 0) ||
1256             hashcmp(sha1, ce->sha1))
1257                 return 0;
1258         /* we return 1 only when we can stat, it is a regular file,
1259          * stat information matches, and sha1 recorded in the cache
1260          * matches.  I.e. we know the file in the work tree really is
1261          * the same as the <name, sha1> pair.
1262          */
1263         return 1;
1264 }
1265
1266 static struct sha1_size_cache {
1267         unsigned char sha1[20];
1268         unsigned long size;
1269 } **sha1_size_cache;
1270 static int sha1_size_cache_nr, sha1_size_cache_alloc;
1271
1272 static struct sha1_size_cache *locate_size_cache(unsigned char *sha1,
1273                                                  int find_only,
1274                                                  unsigned long size)
1275 {
1276         int first, last;
1277         struct sha1_size_cache *e;
1278
1279         first = 0;
1280         last = sha1_size_cache_nr;
1281         while (last > first) {
1282                 int cmp, next = (last + first) >> 1;
1283                 e = sha1_size_cache[next];
1284                 cmp = hashcmp(e->sha1, sha1);
1285                 if (!cmp)
1286                         return e;
1287                 if (cmp < 0) {
1288                         last = next;
1289                         continue;
1290                 }
1291                 first = next+1;
1292         }
1293         /* not found */
1294         if (find_only)
1295                 return NULL;
1296         /* insert to make it at "first" */
1297         if (sha1_size_cache_alloc <= sha1_size_cache_nr) {
1298                 sha1_size_cache_alloc = alloc_nr(sha1_size_cache_alloc);
1299                 sha1_size_cache = xrealloc(sha1_size_cache,
1300                                            sha1_size_cache_alloc *
1301                                            sizeof(*sha1_size_cache));
1302         }
1303         sha1_size_cache_nr++;
1304         if (first < sha1_size_cache_nr)
1305                 memmove(sha1_size_cache + first + 1, sha1_size_cache + first,
1306                         (sha1_size_cache_nr - first - 1) *
1307                         sizeof(*sha1_size_cache));
1308         e = xmalloc(sizeof(struct sha1_size_cache));
1309         sha1_size_cache[first] = e;
1310         hashcpy(e->sha1, sha1);
1311         e->size = size;
1312         return e;
1313 }
1314
1315 /*
1316  * While doing rename detection and pickaxe operation, we may need to
1317  * grab the data for the blob (or file) for our own in-core comparison.
1318  * diff_filespec has data and size fields for this purpose.
1319  */
1320 int diff_populate_filespec(struct diff_filespec *s, int size_only)
1321 {
1322         int err = 0;
1323         if (!DIFF_FILE_VALID(s))
1324                 die("internal error: asking to populate invalid file.");
1325         if (S_ISDIR(s->mode))
1326                 return -1;
1327
1328         if (!use_size_cache)
1329                 size_only = 0;
1330
1331         if (s->data)
1332                 return err;
1333         if (!s->sha1_valid ||
1334             reuse_worktree_file(s->path, s->sha1, 0)) {
1335                 struct stat st;
1336                 int fd;
1337                 if (lstat(s->path, &st) < 0) {
1338                         if (errno == ENOENT) {
1339                         err_empty:
1340                                 err = -1;
1341                         empty:
1342                                 s->data = (char *)"";
1343                                 s->size = 0;
1344                                 return err;
1345                         }
1346                 }
1347                 s->size = st.st_size;
1348                 if (!s->size)
1349                         goto empty;
1350                 if (size_only)
1351                         return 0;
1352                 if (S_ISLNK(st.st_mode)) {
1353                         int ret;
1354                         s->data = xmalloc(s->size);
1355                         s->should_free = 1;
1356                         ret = readlink(s->path, s->data, s->size);
1357                         if (ret < 0) {
1358                                 free(s->data);
1359                                 goto err_empty;
1360                         }
1361                         return 0;
1362                 }
1363                 fd = open(s->path, O_RDONLY);
1364                 if (fd < 0)
1365                         goto err_empty;
1366                 s->data = xmmap(NULL, s->size, PROT_READ, MAP_PRIVATE, fd, 0);
1367                 close(fd);
1368                 s->should_munmap = 1;
1369                 /* FIXME! CRLF -> LF conversion goes here, based on "s->path" */
1370         }
1371         else {
1372                 char type[20];
1373                 struct sha1_size_cache *e;
1374
1375                 if (size_only) {
1376                         e = locate_size_cache(s->sha1, 1, 0);
1377                         if (e) {
1378                                 s->size = e->size;
1379                                 return 0;
1380                         }
1381                         if (!sha1_object_info(s->sha1, type, &s->size))
1382                                 locate_size_cache(s->sha1, 0, s->size);
1383                 }
1384                 else {
1385                         s->data = read_sha1_file(s->sha1, type, &s->size);
1386                         s->should_free = 1;
1387                 }
1388         }
1389         return 0;
1390 }
1391
1392 void diff_free_filespec_data(struct diff_filespec *s)
1393 {
1394         if (s->should_free)
1395                 free(s->data);
1396         else if (s->should_munmap)
1397                 munmap(s->data, s->size);
1398         s->should_free = s->should_munmap = 0;
1399         s->data = NULL;
1400         free(s->cnt_data);
1401         s->cnt_data = NULL;
1402 }
1403
1404 static void prep_temp_blob(struct diff_tempfile *temp,
1405                            void *blob,
1406                            unsigned long size,
1407                            const unsigned char *sha1,
1408                            int mode)
1409 {
1410         int fd;
1411
1412         fd = git_mkstemp(temp->tmp_path, TEMPFILE_PATH_LEN, ".diff_XXXXXX");
1413         if (fd < 0)
1414                 die("unable to create temp-file");
1415         if (write_in_full(fd, blob, size) != size)
1416                 die("unable to write temp-file");
1417         close(fd);
1418         temp->name = temp->tmp_path;
1419         strcpy(temp->hex, sha1_to_hex(sha1));
1420         temp->hex[40] = 0;
1421         sprintf(temp->mode, "%06o", mode);
1422 }
1423
1424 static void prepare_temp_file(const char *name,
1425                               struct diff_tempfile *temp,
1426                               struct diff_filespec *one)
1427 {
1428         if (!DIFF_FILE_VALID(one)) {
1429         not_a_valid_file:
1430                 /* A '-' entry produces this for file-2, and
1431                  * a '+' entry produces this for file-1.
1432                  */
1433                 temp->name = "/dev/null";
1434                 strcpy(temp->hex, ".");
1435                 strcpy(temp->mode, ".");
1436                 return;
1437         }
1438
1439         if (!one->sha1_valid ||
1440             reuse_worktree_file(name, one->sha1, 1)) {
1441                 struct stat st;
1442                 if (lstat(name, &st) < 0) {
1443                         if (errno == ENOENT)
1444                                 goto not_a_valid_file;
1445                         die("stat(%s): %s", name, strerror(errno));
1446                 }
1447                 if (S_ISLNK(st.st_mode)) {
1448                         int ret;
1449                         char buf[PATH_MAX + 1]; /* ought to be SYMLINK_MAX */
1450                         if (sizeof(buf) <= st.st_size)
1451                                 die("symlink too long: %s", name);
1452                         ret = readlink(name, buf, st.st_size);
1453                         if (ret < 0)
1454                                 die("readlink(%s)", name);
1455                         prep_temp_blob(temp, buf, st.st_size,
1456                                        (one->sha1_valid ?
1457                                         one->sha1 : null_sha1),
1458                                        (one->sha1_valid ?
1459                                         one->mode : S_IFLNK));
1460                 }
1461                 else {
1462                         /* we can borrow from the file in the work tree */
1463                         temp->name = name;
1464                         if (!one->sha1_valid)
1465                                 strcpy(temp->hex, sha1_to_hex(null_sha1));
1466                         else
1467                                 strcpy(temp->hex, sha1_to_hex(one->sha1));
1468                         /* Even though we may sometimes borrow the
1469                          * contents from the work tree, we always want
1470                          * one->mode.  mode is trustworthy even when
1471                          * !(one->sha1_valid), as long as
1472                          * DIFF_FILE_VALID(one).
1473                          */
1474                         sprintf(temp->mode, "%06o", one->mode);
1475                 }
1476                 return;
1477         }
1478         else {
1479                 if (diff_populate_filespec(one, 0))
1480                         die("cannot read data blob for %s", one->path);
1481                 prep_temp_blob(temp, one->data, one->size,
1482                                one->sha1, one->mode);
1483         }
1484 }
1485
1486 static void remove_tempfile(void)
1487 {
1488         int i;
1489
1490         for (i = 0; i < 2; i++)
1491                 if (diff_temp[i].name == diff_temp[i].tmp_path) {
1492                         unlink(diff_temp[i].name);
1493                         diff_temp[i].name = NULL;
1494                 }
1495 }
1496
1497 static void remove_tempfile_on_signal(int signo)
1498 {
1499         remove_tempfile();
1500         signal(SIGINT, SIG_DFL);
1501         raise(signo);
1502 }
1503
1504 static int spawn_prog(const char *pgm, const char **arg)
1505 {
1506         pid_t pid;
1507         int status;
1508
1509         fflush(NULL);
1510         pid = fork();
1511         if (pid < 0)
1512                 die("unable to fork");
1513         if (!pid) {
1514                 execvp(pgm, (char *const*) arg);
1515                 exit(255);
1516         }
1517
1518         while (waitpid(pid, &status, 0) < 0) {
1519                 if (errno == EINTR)
1520                         continue;
1521                 return -1;
1522         }
1523
1524         /* Earlier we did not check the exit status because
1525          * diff exits non-zero if files are different, and
1526          * we are not interested in knowing that.  It was a
1527          * mistake which made it harder to quit a diff-*
1528          * session that uses the git-apply-patch-script as
1529          * the GIT_EXTERNAL_DIFF.  A custom GIT_EXTERNAL_DIFF
1530          * should also exit non-zero only when it wants to
1531          * abort the entire diff-* session.
1532          */
1533         if (WIFEXITED(status) && !WEXITSTATUS(status))
1534                 return 0;
1535         return -1;
1536 }
1537
1538 /* An external diff command takes:
1539  *
1540  * diff-cmd name infile1 infile1-sha1 infile1-mode \
1541  *               infile2 infile2-sha1 infile2-mode [ rename-to ]
1542  *
1543  */
1544 static void run_external_diff(const char *pgm,
1545                               const char *name,
1546                               const char *other,
1547                               struct diff_filespec *one,
1548                               struct diff_filespec *two,
1549                               const char *xfrm_msg,
1550                               int complete_rewrite)
1551 {
1552         const char *spawn_arg[10];
1553         struct diff_tempfile *temp = diff_temp;
1554         int retval;
1555         static int atexit_asked = 0;
1556         const char *othername;
1557         const char **arg = &spawn_arg[0];
1558
1559         othername = (other? other : name);
1560         if (one && two) {
1561                 prepare_temp_file(name, &temp[0], one);
1562                 prepare_temp_file(othername, &temp[1], two);
1563                 if (! atexit_asked &&
1564                     (temp[0].name == temp[0].tmp_path ||
1565                      temp[1].name == temp[1].tmp_path)) {
1566                         atexit_asked = 1;
1567                         atexit(remove_tempfile);
1568                 }
1569                 signal(SIGINT, remove_tempfile_on_signal);
1570         }
1571
1572         if (one && two) {
1573                 *arg++ = pgm;
1574                 *arg++ = name;
1575                 *arg++ = temp[0].name;
1576                 *arg++ = temp[0].hex;
1577                 *arg++ = temp[0].mode;
1578                 *arg++ = temp[1].name;
1579                 *arg++ = temp[1].hex;
1580                 *arg++ = temp[1].mode;
1581                 if (other) {
1582                         *arg++ = other;
1583                         *arg++ = xfrm_msg;
1584                 }
1585         } else {
1586                 *arg++ = pgm;
1587                 *arg++ = name;
1588         }
1589         *arg = NULL;
1590         retval = spawn_prog(pgm, spawn_arg);
1591         remove_tempfile();
1592         if (retval) {
1593                 fprintf(stderr, "external diff died, stopping at %s.\n", name);
1594                 exit(1);
1595         }
1596 }
1597
1598 static void run_diff_cmd(const char *pgm,
1599                          const char *name,
1600                          const char *other,
1601                          struct diff_filespec *one,
1602                          struct diff_filespec *two,
1603                          const char *xfrm_msg,
1604                          struct diff_options *o,
1605                          int complete_rewrite)
1606 {
1607         if (pgm) {
1608                 run_external_diff(pgm, name, other, one, two, xfrm_msg,
1609                                   complete_rewrite);
1610                 return;
1611         }
1612         if (one && two)
1613                 builtin_diff(name, other ? other : name,
1614                              one, two, xfrm_msg, o, complete_rewrite);
1615         else
1616                 printf("* Unmerged path %s\n", name);
1617 }
1618
1619 static void diff_fill_sha1_info(struct diff_filespec *one)
1620 {
1621         if (DIFF_FILE_VALID(one)) {
1622                 if (!one->sha1_valid) {
1623                         struct stat st;
1624                         if (lstat(one->path, &st) < 0)
1625                                 die("stat %s", one->path);
1626                         if (index_path(one->sha1, one->path, &st, 0))
1627                                 die("cannot hash %s\n", one->path);
1628                 }
1629         }
1630         else
1631                 hashclr(one->sha1);
1632 }
1633
1634 static void run_diff(struct diff_filepair *p, struct diff_options *o)
1635 {
1636         const char *pgm = external_diff();
1637         char msg[PATH_MAX*2+300], *xfrm_msg;
1638         struct diff_filespec *one;
1639         struct diff_filespec *two;
1640         const char *name;
1641         const char *other;
1642         char *name_munged, *other_munged;
1643         int complete_rewrite = 0;
1644         int len;
1645
1646         if (DIFF_PAIR_UNMERGED(p)) {
1647                 /* unmerged */
1648                 run_diff_cmd(pgm, p->one->path, NULL, NULL, NULL, NULL, o, 0);
1649                 return;
1650         }
1651
1652         name = p->one->path;
1653         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
1654         name_munged = quote_one(name);
1655         other_munged = quote_one(other);
1656         one = p->one; two = p->two;
1657
1658         diff_fill_sha1_info(one);
1659         diff_fill_sha1_info(two);
1660
1661         len = 0;
1662         switch (p->status) {
1663         case DIFF_STATUS_COPIED:
1664                 len += snprintf(msg + len, sizeof(msg) - len,
1665                                 "similarity index %d%%\n"
1666                                 "copy from %s\n"
1667                                 "copy to %s\n",
1668                                 (int)(0.5 + p->score * 100.0/MAX_SCORE),
1669                                 name_munged, other_munged);
1670                 break;
1671         case DIFF_STATUS_RENAMED:
1672                 len += snprintf(msg + len, sizeof(msg) - len,
1673                                 "similarity index %d%%\n"
1674                                 "rename from %s\n"
1675                                 "rename to %s\n",
1676                                 (int)(0.5 + p->score * 100.0/MAX_SCORE),
1677                                 name_munged, other_munged);
1678                 break;
1679         case DIFF_STATUS_MODIFIED:
1680                 if (p->score) {
1681                         len += snprintf(msg + len, sizeof(msg) - len,
1682                                         "dissimilarity index %d%%\n",
1683                                         (int)(0.5 + p->score *
1684                                               100.0/MAX_SCORE));
1685                         complete_rewrite = 1;
1686                         break;
1687                 }
1688                 /* fallthru */
1689         default:
1690                 /* nothing */
1691                 ;
1692         }
1693
1694         if (hashcmp(one->sha1, two->sha1)) {
1695                 int abbrev = o->full_index ? 40 : DEFAULT_ABBREV;
1696
1697                 if (o->binary) {
1698                         mmfile_t mf;
1699                         if ((!fill_mmfile(&mf, one) && mmfile_is_binary(&mf)) ||
1700                             (!fill_mmfile(&mf, two) && mmfile_is_binary(&mf)))
1701                                 abbrev = 40;
1702                 }
1703                 len += snprintf(msg + len, sizeof(msg) - len,
1704                                 "index %.*s..%.*s",
1705                                 abbrev, sha1_to_hex(one->sha1),
1706                                 abbrev, sha1_to_hex(two->sha1));
1707                 if (one->mode == two->mode)
1708                         len += snprintf(msg + len, sizeof(msg) - len,
1709                                         " %06o", one->mode);
1710                 len += snprintf(msg + len, sizeof(msg) - len, "\n");
1711         }
1712
1713         if (len)
1714                 msg[--len] = 0;
1715         xfrm_msg = len ? msg : NULL;
1716
1717         if (!pgm &&
1718             DIFF_FILE_VALID(one) && DIFF_FILE_VALID(two) &&
1719             (S_IFMT & one->mode) != (S_IFMT & two->mode)) {
1720                 /* a filepair that changes between file and symlink
1721                  * needs to be split into deletion and creation.
1722                  */
1723                 struct diff_filespec *null = alloc_filespec(two->path);
1724                 run_diff_cmd(NULL, name, other, one, null, xfrm_msg, o, 0);
1725                 free(null);
1726                 null = alloc_filespec(one->path);
1727                 run_diff_cmd(NULL, name, other, null, two, xfrm_msg, o, 0);
1728                 free(null);
1729         }
1730         else
1731                 run_diff_cmd(pgm, name, other, one, two, xfrm_msg, o,
1732                              complete_rewrite);
1733
1734         free(name_munged);
1735         free(other_munged);
1736 }
1737
1738 static void run_diffstat(struct diff_filepair *p, struct diff_options *o,
1739                          struct diffstat_t *diffstat)
1740 {
1741         const char *name;
1742         const char *other;
1743         int complete_rewrite = 0;
1744
1745         if (DIFF_PAIR_UNMERGED(p)) {
1746                 /* unmerged */
1747                 builtin_diffstat(p->one->path, NULL, NULL, NULL, diffstat, o, 0);
1748                 return;
1749         }
1750
1751         name = p->one->path;
1752         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
1753
1754         diff_fill_sha1_info(p->one);
1755         diff_fill_sha1_info(p->two);
1756
1757         if (p->status == DIFF_STATUS_MODIFIED && p->score)
1758                 complete_rewrite = 1;
1759         builtin_diffstat(name, other, p->one, p->two, diffstat, o, complete_rewrite);
1760 }
1761
1762 static void run_checkdiff(struct diff_filepair *p, struct diff_options *o)
1763 {
1764         const char *name;
1765         const char *other;
1766
1767         if (DIFF_PAIR_UNMERGED(p)) {
1768                 /* unmerged */
1769                 return;
1770         }
1771
1772         name = p->one->path;
1773         other = (strcmp(name, p->two->path) ? p->two->path : NULL);
1774
1775         diff_fill_sha1_info(p->one);
1776         diff_fill_sha1_info(p->two);
1777
1778         builtin_checkdiff(name, other, p->one, p->two);
1779 }
1780
1781 void diff_setup(struct diff_options *options)
1782 {
1783         memset(options, 0, sizeof(*options));
1784         options->line_termination = '\n';
1785         options->break_opt = -1;
1786         options->rename_limit = -1;
1787         options->context = 3;
1788         options->msg_sep = "";
1789
1790         options->change = diff_change;
1791         options->add_remove = diff_addremove;
1792         options->color_diff = diff_use_color_default;
1793         options->detect_rename = diff_detect_rename_default;
1794 }
1795
1796 int diff_setup_done(struct diff_options *options)
1797 {
1798         int count = 0;
1799
1800         if (options->output_format & DIFF_FORMAT_NAME)
1801                 count++;
1802         if (options->output_format & DIFF_FORMAT_NAME_STATUS)
1803                 count++;
1804         if (options->output_format & DIFF_FORMAT_CHECKDIFF)
1805                 count++;
1806         if (options->output_format & DIFF_FORMAT_NO_OUTPUT)
1807                 count++;
1808         if (count > 1)
1809                 die("--name-only, --name-status, --check and -s are mutually exclusive");
1810
1811         if (options->find_copies_harder)
1812                 options->detect_rename = DIFF_DETECT_COPY;
1813
1814         if (options->output_format & (DIFF_FORMAT_NAME |
1815                                       DIFF_FORMAT_NAME_STATUS |
1816                                       DIFF_FORMAT_CHECKDIFF |
1817                                       DIFF_FORMAT_NO_OUTPUT))
1818                 options->output_format &= ~(DIFF_FORMAT_RAW |
1819                                             DIFF_FORMAT_NUMSTAT |
1820                                             DIFF_FORMAT_DIFFSTAT |
1821                                             DIFF_FORMAT_SHORTSTAT |
1822                                             DIFF_FORMAT_SUMMARY |
1823                                             DIFF_FORMAT_PATCH);
1824
1825         /*
1826          * These cases always need recursive; we do not drop caller-supplied
1827          * recursive bits for other formats here.
1828          */
1829         if (options->output_format & (DIFF_FORMAT_PATCH |
1830                                       DIFF_FORMAT_NUMSTAT |
1831                                       DIFF_FORMAT_DIFFSTAT |
1832                                       DIFF_FORMAT_SHORTSTAT |
1833                                       DIFF_FORMAT_SUMMARY |
1834                                       DIFF_FORMAT_CHECKDIFF))
1835                 options->recursive = 1;
1836         /*
1837          * Also pickaxe would not work very well if you do not say recursive
1838          */
1839         if (options->pickaxe)
1840                 options->recursive = 1;
1841
1842         if (options->detect_rename && options->rename_limit < 0)
1843                 options->rename_limit = diff_rename_limit_default;
1844         if (options->setup & DIFF_SETUP_USE_CACHE) {
1845                 if (!active_cache)
1846                         /* read-cache does not die even when it fails
1847                          * so it is safe for us to do this here.  Also
1848                          * it does not smudge active_cache or active_nr
1849                          * when it fails, so we do not have to worry about
1850                          * cleaning it up ourselves either.
1851                          */
1852                         read_cache();
1853         }
1854         if (options->setup & DIFF_SETUP_USE_SIZE_CACHE)
1855                 use_size_cache = 1;
1856         if (options->abbrev <= 0 || 40 < options->abbrev)
1857                 options->abbrev = 40; /* full */
1858
1859         return 0;
1860 }
1861
1862 static int opt_arg(const char *arg, int arg_short, const char *arg_long, int *val)
1863 {
1864         char c, *eq;
1865         int len;
1866
1867         if (*arg != '-')
1868                 return 0;
1869         c = *++arg;
1870         if (!c)
1871                 return 0;
1872         if (c == arg_short) {
1873                 c = *++arg;
1874                 if (!c)
1875                         return 1;
1876                 if (val && isdigit(c)) {
1877                         char *end;
1878                         int n = strtoul(arg, &end, 10);
1879                         if (*end)
1880                                 return 0;
1881                         *val = n;
1882                         return 1;
1883                 }
1884                 return 0;
1885         }
1886         if (c != '-')
1887                 return 0;
1888         arg++;
1889         eq = strchr(arg, '=');
1890         if (eq)
1891                 len = eq - arg;
1892         else
1893                 len = strlen(arg);
1894         if (!len || strncmp(arg, arg_long, len))
1895                 return 0;
1896         if (eq) {
1897                 int n;
1898                 char *end;
1899                 if (!isdigit(*++eq))
1900                         return 0;
1901                 n = strtoul(eq, &end, 10);
1902                 if (*end)
1903                         return 0;
1904                 *val = n;
1905         }
1906         return 1;
1907 }
1908
1909 int diff_opt_parse(struct diff_options *options, const char **av, int ac)
1910 {
1911         const char *arg = av[0];
1912         if (!strcmp(arg, "-p") || !strcmp(arg, "-u"))
1913                 options->output_format |= DIFF_FORMAT_PATCH;
1914         else if (opt_arg(arg, 'U', "unified", &options->context))
1915                 options->output_format |= DIFF_FORMAT_PATCH;
1916         else if (!strcmp(arg, "--raw"))
1917                 options->output_format |= DIFF_FORMAT_RAW;
1918         else if (!strcmp(arg, "--patch-with-raw")) {
1919                 options->output_format |= DIFF_FORMAT_PATCH | DIFF_FORMAT_RAW;
1920         }
1921         else if (!strcmp(arg, "--numstat")) {
1922                 options->output_format |= DIFF_FORMAT_NUMSTAT;
1923         }
1924         else if (!strcmp(arg, "--shortstat")) {
1925                 options->output_format |= DIFF_FORMAT_SHORTSTAT;
1926         }
1927         else if (!strncmp(arg, "--stat", 6)) {
1928                 char *end;
1929                 int width = options->stat_width;
1930                 int name_width = options->stat_name_width;
1931                 arg += 6;
1932                 end = (char *)arg;
1933
1934                 switch (*arg) {
1935                 case '-':
1936                         if (!strncmp(arg, "-width=", 7))
1937                                 width = strtoul(arg + 7, &end, 10);
1938                         else if (!strncmp(arg, "-name-width=", 12))
1939                                 name_width = strtoul(arg + 12, &end, 10);
1940                         break;
1941                 case '=':
1942                         width = strtoul(arg+1, &end, 10);
1943                         if (*end == ',')
1944                                 name_width = strtoul(end+1, &end, 10);
1945                 }
1946
1947                 /* Important! This checks all the error cases! */
1948                 if (*end)
1949                         return 0;
1950                 options->output_format |= DIFF_FORMAT_DIFFSTAT;
1951                 options->stat_name_width = name_width;
1952                 options->stat_width = width;
1953         }
1954         else if (!strcmp(arg, "--check"))
1955                 options->output_format |= DIFF_FORMAT_CHECKDIFF;
1956         else if (!strcmp(arg, "--summary"))
1957                 options->output_format |= DIFF_FORMAT_SUMMARY;
1958         else if (!strcmp(arg, "--patch-with-stat")) {
1959                 options->output_format |= DIFF_FORMAT_PATCH | DIFF_FORMAT_DIFFSTAT;
1960         }
1961         else if (!strcmp(arg, "-z"))
1962                 options->line_termination = 0;
1963         else if (!strncmp(arg, "-l", 2))
1964                 options->rename_limit = strtoul(arg+2, NULL, 10);
1965         else if (!strcmp(arg, "--full-index"))
1966                 options->full_index = 1;
1967         else if (!strcmp(arg, "--binary")) {
1968                 options->output_format |= DIFF_FORMAT_PATCH;
1969                 options->binary = 1;
1970         }
1971         else if (!strcmp(arg, "-a") || !strcmp(arg, "--text")) {
1972                 options->text = 1;
1973         }
1974         else if (!strcmp(arg, "--name-only"))
1975                 options->output_format |= DIFF_FORMAT_NAME;
1976         else if (!strcmp(arg, "--name-status"))
1977                 options->output_format |= DIFF_FORMAT_NAME_STATUS;
1978         else if (!strcmp(arg, "-R"))
1979                 options->reverse_diff = 1;
1980         else if (!strncmp(arg, "-S", 2))
1981                 options->pickaxe = arg + 2;
1982         else if (!strcmp(arg, "-s")) {
1983                 options->output_format |= DIFF_FORMAT_NO_OUTPUT;
1984         }
1985         else if (!strncmp(arg, "-O", 2))
1986                 options->orderfile = arg + 2;
1987         else if (!strncmp(arg, "--diff-filter=", 14))
1988                 options->filter = arg + 14;
1989         else if (!strcmp(arg, "--pickaxe-all"))
1990                 options->pickaxe_opts = DIFF_PICKAXE_ALL;
1991         else if (!strcmp(arg, "--pickaxe-regex"))
1992                 options->pickaxe_opts = DIFF_PICKAXE_REGEX;
1993         else if (!strncmp(arg, "-B", 2)) {
1994                 if ((options->break_opt =
1995                      diff_scoreopt_parse(arg)) == -1)
1996                         return -1;
1997         }
1998         else if (!strncmp(arg, "-M", 2)) {
1999                 if ((options->rename_score =
2000                      diff_scoreopt_parse(arg)) == -1)
2001                         return -1;
2002                 options->detect_rename = DIFF_DETECT_RENAME;
2003         }
2004         else if (!strncmp(arg, "-C", 2)) {
2005                 if ((options->rename_score =
2006                      diff_scoreopt_parse(arg)) == -1)
2007                         return -1;
2008                 options->detect_rename = DIFF_DETECT_COPY;
2009         }
2010         else if (!strcmp(arg, "--find-copies-harder"))
2011                 options->find_copies_harder = 1;
2012         else if (!strcmp(arg, "--abbrev"))
2013                 options->abbrev = DEFAULT_ABBREV;
2014         else if (!strncmp(arg, "--abbrev=", 9)) {
2015                 options->abbrev = strtoul(arg + 9, NULL, 10);
2016                 if (options->abbrev < MINIMUM_ABBREV)
2017                         options->abbrev = MINIMUM_ABBREV;
2018                 else if (40 < options->abbrev)
2019                         options->abbrev = 40;
2020         }
2021         else if (!strcmp(arg, "--color"))
2022                 options->color_diff = 1;
2023         else if (!strcmp(arg, "--no-color"))
2024                 options->color_diff = 0;
2025         else if (!strcmp(arg, "-w") || !strcmp(arg, "--ignore-all-space"))
2026                 options->xdl_opts |= XDF_IGNORE_WHITESPACE;
2027         else if (!strcmp(arg, "-b") || !strcmp(arg, "--ignore-space-change"))
2028                 options->xdl_opts |= XDF_IGNORE_WHITESPACE_CHANGE;
2029         else if (!strcmp(arg, "--color-words"))
2030                 options->color_diff = options->color_diff_words = 1;
2031         else if (!strcmp(arg, "--no-renames"))
2032                 options->detect_rename = 0;
2033         else
2034                 return 0;
2035         return 1;
2036 }
2037
2038 static int parse_num(const char **cp_p)
2039 {
2040         unsigned long num, scale;
2041         int ch, dot;
2042         const char *cp = *cp_p;
2043
2044         num = 0;
2045         scale = 1;
2046         dot = 0;
2047         for(;;) {
2048                 ch = *cp;
2049                 if ( !dot && ch == '.' ) {
2050                         scale = 1;
2051                         dot = 1;
2052                 } else if ( ch == '%' ) {
2053                         scale = dot ? scale*100 : 100;
2054                         cp++;   /* % is always at the end */
2055                         break;
2056                 } else if ( ch >= '0' && ch <= '9' ) {
2057                         if ( scale < 100000 ) {
2058                                 scale *= 10;
2059                                 num = (num*10) + (ch-'0');
2060                         }
2061                 } else {
2062                         break;
2063                 }
2064                 cp++;
2065         }
2066         *cp_p = cp;
2067
2068         /* user says num divided by scale and we say internally that
2069          * is MAX_SCORE * num / scale.
2070          */
2071         return (num >= scale) ? MAX_SCORE : (MAX_SCORE * num / scale);
2072 }
2073
2074 int diff_scoreopt_parse(const char *opt)
2075 {
2076         int opt1, opt2, cmd;
2077
2078         if (*opt++ != '-')
2079                 return -1;
2080         cmd = *opt++;
2081         if (cmd != 'M' && cmd != 'C' && cmd != 'B')
2082                 return -1; /* that is not a -M, -C nor -B option */
2083
2084         opt1 = parse_num(&opt);
2085         if (cmd != 'B')
2086                 opt2 = 0;
2087         else {
2088                 if (*opt == 0)
2089                         opt2 = 0;
2090                 else if (*opt != '/')
2091                         return -1; /* we expect -B80/99 or -B80 */
2092                 else {
2093                         opt++;
2094                         opt2 = parse_num(&opt);
2095                 }
2096         }
2097         if (*opt != 0)
2098                 return -1;
2099         return opt1 | (opt2 << 16);
2100 }
2101
2102 struct diff_queue_struct diff_queued_diff;
2103
2104 void diff_q(struct diff_queue_struct *queue, struct diff_filepair *dp)
2105 {
2106         if (queue->alloc <= queue->nr) {
2107                 queue->alloc = alloc_nr(queue->alloc);
2108                 queue->queue = xrealloc(queue->queue,
2109                                         sizeof(dp) * queue->alloc);
2110         }
2111         queue->queue[queue->nr++] = dp;
2112 }
2113
2114 struct diff_filepair *diff_queue(struct diff_queue_struct *queue,
2115                                  struct diff_filespec *one,
2116                                  struct diff_filespec *two)
2117 {
2118         struct diff_filepair *dp = xcalloc(1, sizeof(*dp));
2119         dp->one = one;
2120         dp->two = two;
2121         if (queue)
2122                 diff_q(queue, dp);
2123         return dp;
2124 }
2125
2126 void diff_free_filepair(struct diff_filepair *p)
2127 {
2128         diff_free_filespec_data(p->one);
2129         diff_free_filespec_data(p->two);
2130         free(p->one);
2131         free(p->two);
2132         free(p);
2133 }
2134
2135 /* This is different from find_unique_abbrev() in that
2136  * it stuffs the result with dots for alignment.
2137  */
2138 const char *diff_unique_abbrev(const unsigned char *sha1, int len)
2139 {
2140         int abblen;
2141         const char *abbrev;
2142         if (len == 40)
2143                 return sha1_to_hex(sha1);
2144
2145         abbrev = find_unique_abbrev(sha1, len);
2146         if (!abbrev)
2147                 return sha1_to_hex(sha1);
2148         abblen = strlen(abbrev);
2149         if (abblen < 37) {
2150                 static char hex[41];
2151                 if (len < abblen && abblen <= len + 2)
2152                         sprintf(hex, "%s%.*s", abbrev, len+3-abblen, "..");
2153                 else
2154                         sprintf(hex, "%s...", abbrev);
2155                 return hex;
2156         }
2157         return sha1_to_hex(sha1);
2158 }
2159
2160 static void diff_flush_raw(struct diff_filepair *p,
2161                            struct diff_options *options)
2162 {
2163         int two_paths;
2164         char status[10];
2165         int abbrev = options->abbrev;
2166         const char *path_one, *path_two;
2167         int inter_name_termination = '\t';
2168         int line_termination = options->line_termination;
2169
2170         if (!line_termination)
2171                 inter_name_termination = 0;
2172
2173         path_one = p->one->path;
2174         path_two = p->two->path;
2175         if (line_termination) {
2176                 path_one = quote_one(path_one);
2177                 path_two = quote_one(path_two);
2178         }
2179
2180         if (p->score)
2181                 sprintf(status, "%c%03d", p->status,
2182                         (int)(0.5 + p->score * 100.0/MAX_SCORE));
2183         else {
2184                 status[0] = p->status;
2185                 status[1] = 0;
2186         }
2187         switch (p->status) {
2188         case DIFF_STATUS_COPIED:
2189         case DIFF_STATUS_RENAMED:
2190                 two_paths = 1;
2191                 break;
2192         case DIFF_STATUS_ADDED:
2193         case DIFF_STATUS_DELETED:
2194                 two_paths = 0;
2195                 break;
2196         default:
2197                 two_paths = 0;
2198                 break;
2199         }
2200         if (!(options->output_format & DIFF_FORMAT_NAME_STATUS)) {
2201                 printf(":%06o %06o %s ",
2202                        p->one->mode, p->two->mode,
2203                        diff_unique_abbrev(p->one->sha1, abbrev));
2204                 printf("%s ",
2205                        diff_unique_abbrev(p->two->sha1, abbrev));
2206         }
2207         printf("%s%c%s", status, inter_name_termination, path_one);
2208         if (two_paths)
2209                 printf("%c%s", inter_name_termination, path_two);
2210         putchar(line_termination);
2211         if (path_one != p->one->path)
2212                 free((void*)path_one);
2213         if (path_two != p->two->path)
2214                 free((void*)path_two);
2215 }
2216
2217 static void diff_flush_name(struct diff_filepair *p, struct diff_options *opt)
2218 {
2219         char *path = p->two->path;
2220
2221         if (opt->line_termination)
2222                 path = quote_one(p->two->path);
2223         printf("%s%c", path, opt->line_termination);
2224         if (p->two->path != path)
2225                 free(path);
2226 }
2227
2228 int diff_unmodified_pair(struct diff_filepair *p)
2229 {
2230         /* This function is written stricter than necessary to support
2231          * the currently implemented transformers, but the idea is to
2232          * let transformers to produce diff_filepairs any way they want,
2233          * and filter and clean them up here before producing the output.
2234          */
2235         struct diff_filespec *one, *two;
2236
2237         if (DIFF_PAIR_UNMERGED(p))
2238                 return 0; /* unmerged is interesting */
2239
2240         one = p->one;
2241         two = p->two;
2242
2243         /* deletion, addition, mode or type change
2244          * and rename are all interesting.
2245          */
2246         if (DIFF_FILE_VALID(one) != DIFF_FILE_VALID(two) ||
2247             DIFF_PAIR_MODE_CHANGED(p) ||
2248             strcmp(one->path, two->path))
2249                 return 0;
2250
2251         /* both are valid and point at the same path.  that is, we are
2252          * dealing with a change.
2253          */
2254         if (one->sha1_valid && two->sha1_valid &&
2255             !hashcmp(one->sha1, two->sha1))
2256                 return 1; /* no change */
2257         if (!one->sha1_valid && !two->sha1_valid)
2258                 return 1; /* both look at the same file on the filesystem. */
2259         return 0;
2260 }
2261
2262 static void diff_flush_patch(struct diff_filepair *p, struct diff_options *o)
2263 {
2264         if (diff_unmodified_pair(p))
2265                 return;
2266
2267         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2268             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2269                 return; /* no tree diffs in patch format */
2270
2271         run_diff(p, o);
2272 }
2273
2274 static void diff_flush_stat(struct diff_filepair *p, struct diff_options *o,
2275                             struct diffstat_t *diffstat)
2276 {
2277         if (diff_unmodified_pair(p))
2278                 return;
2279
2280         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2281             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2282                 return; /* no tree diffs in patch format */
2283
2284         run_diffstat(p, o, diffstat);
2285 }
2286
2287 static void diff_flush_checkdiff(struct diff_filepair *p,
2288                 struct diff_options *o)
2289 {
2290         if (diff_unmodified_pair(p))
2291                 return;
2292
2293         if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2294             (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2295                 return; /* no tree diffs in patch format */
2296
2297         run_checkdiff(p, o);
2298 }
2299
2300 int diff_queue_is_empty(void)
2301 {
2302         struct diff_queue_struct *q = &diff_queued_diff;
2303         int i;
2304         for (i = 0; i < q->nr; i++)
2305                 if (!diff_unmodified_pair(q->queue[i]))
2306                         return 0;
2307         return 1;
2308 }
2309
2310 #if DIFF_DEBUG
2311 void diff_debug_filespec(struct diff_filespec *s, int x, const char *one)
2312 {
2313         fprintf(stderr, "queue[%d] %s (%s) %s %06o %s\n",
2314                 x, one ? one : "",
2315                 s->path,
2316                 DIFF_FILE_VALID(s) ? "valid" : "invalid",
2317                 s->mode,
2318                 s->sha1_valid ? sha1_to_hex(s->sha1) : "");
2319         fprintf(stderr, "queue[%d] %s size %lu flags %d\n",
2320                 x, one ? one : "",
2321                 s->size, s->xfrm_flags);
2322 }
2323
2324 void diff_debug_filepair(const struct diff_filepair *p, int i)
2325 {
2326         diff_debug_filespec(p->one, i, "one");
2327         diff_debug_filespec(p->two, i, "two");
2328         fprintf(stderr, "score %d, status %c stays %d broken %d\n",
2329                 p->score, p->status ? p->status : '?',
2330                 p->source_stays, p->broken_pair);
2331 }
2332
2333 void diff_debug_queue(const char *msg, struct diff_queue_struct *q)
2334 {
2335         int i;
2336         if (msg)
2337                 fprintf(stderr, "%s\n", msg);
2338         fprintf(stderr, "q->nr = %d\n", q->nr);
2339         for (i = 0; i < q->nr; i++) {
2340                 struct diff_filepair *p = q->queue[i];
2341                 diff_debug_filepair(p, i);
2342         }
2343 }
2344 #endif
2345
2346 static void diff_resolve_rename_copy(void)
2347 {
2348         int i, j;
2349         struct diff_filepair *p, *pp;
2350         struct diff_queue_struct *q = &diff_queued_diff;
2351
2352         diff_debug_queue("resolve-rename-copy", q);
2353
2354         for (i = 0; i < q->nr; i++) {
2355                 p = q->queue[i];
2356                 p->status = 0; /* undecided */
2357                 if (DIFF_PAIR_UNMERGED(p))
2358                         p->status = DIFF_STATUS_UNMERGED;
2359                 else if (!DIFF_FILE_VALID(p->one))
2360                         p->status = DIFF_STATUS_ADDED;
2361                 else if (!DIFF_FILE_VALID(p->two))
2362                         p->status = DIFF_STATUS_DELETED;
2363                 else if (DIFF_PAIR_TYPE_CHANGED(p))
2364                         p->status = DIFF_STATUS_TYPE_CHANGED;
2365
2366                 /* from this point on, we are dealing with a pair
2367                  * whose both sides are valid and of the same type, i.e.
2368                  * either in-place edit or rename/copy edit.
2369                  */
2370                 else if (DIFF_PAIR_RENAME(p)) {
2371                         if (p->source_stays) {
2372                                 p->status = DIFF_STATUS_COPIED;
2373                                 continue;
2374                         }
2375                         /* See if there is some other filepair that
2376                          * copies from the same source as us.  If so
2377                          * we are a copy.  Otherwise we are either a
2378                          * copy if the path stays, or a rename if it
2379                          * does not, but we already handled "stays" case.
2380                          */
2381                         for (j = i + 1; j < q->nr; j++) {
2382                                 pp = q->queue[j];
2383                                 if (strcmp(pp->one->path, p->one->path))
2384                                         continue; /* not us */
2385                                 if (!DIFF_PAIR_RENAME(pp))
2386                                         continue; /* not a rename/copy */
2387                                 /* pp is a rename/copy from the same source */
2388                                 p->status = DIFF_STATUS_COPIED;
2389                                 break;
2390                         }
2391                         if (!p->status)
2392                                 p->status = DIFF_STATUS_RENAMED;
2393                 }
2394                 else if (hashcmp(p->one->sha1, p->two->sha1) ||
2395                          p->one->mode != p->two->mode)
2396                         p->status = DIFF_STATUS_MODIFIED;
2397                 else {
2398                         /* This is a "no-change" entry and should not
2399                          * happen anymore, but prepare for broken callers.
2400                          */
2401                         error("feeding unmodified %s to diffcore",
2402                               p->one->path);
2403                         p->status = DIFF_STATUS_UNKNOWN;
2404                 }
2405         }
2406         diff_debug_queue("resolve-rename-copy done", q);
2407 }
2408
2409 static int check_pair_status(struct diff_filepair *p)
2410 {
2411         switch (p->status) {
2412         case DIFF_STATUS_UNKNOWN:
2413                 return 0;
2414         case 0:
2415                 die("internal error in diff-resolve-rename-copy");
2416         default:
2417                 return 1;
2418         }
2419 }
2420
2421 static void flush_one_pair(struct diff_filepair *p, struct diff_options *opt)
2422 {
2423         int fmt = opt->output_format;
2424
2425         if (fmt & DIFF_FORMAT_CHECKDIFF)
2426                 diff_flush_checkdiff(p, opt);
2427         else if (fmt & (DIFF_FORMAT_RAW | DIFF_FORMAT_NAME_STATUS))
2428                 diff_flush_raw(p, opt);
2429         else if (fmt & DIFF_FORMAT_NAME)
2430                 diff_flush_name(p, opt);
2431 }
2432
2433 static void show_file_mode_name(const char *newdelete, struct diff_filespec *fs)
2434 {
2435         char *name = quote_one(fs->path);
2436         if (fs->mode)
2437                 printf(" %s mode %06o %s\n", newdelete, fs->mode, name);
2438         else
2439                 printf(" %s %s\n", newdelete, name);
2440         free(name);
2441 }
2442
2443
2444 static void show_mode_change(struct diff_filepair *p, int show_name)
2445 {
2446         if (p->one->mode && p->two->mode && p->one->mode != p->two->mode) {
2447                 if (show_name) {
2448                         char *name = quote_one(p->two->path);
2449                         printf(" mode change %06o => %06o %s\n",
2450                                p->one->mode, p->two->mode, name);
2451                         free(name);
2452                 }
2453                 else
2454                         printf(" mode change %06o => %06o\n",
2455                                p->one->mode, p->two->mode);
2456         }
2457 }
2458
2459 static void show_rename_copy(const char *renamecopy, struct diff_filepair *p)
2460 {
2461         char *names = pprint_rename(p->one->path, p->two->path);
2462
2463         printf(" %s %s (%d%%)\n", renamecopy, names,
2464                (int)(0.5 + p->score * 100.0/MAX_SCORE));
2465         free(names);
2466         show_mode_change(p, 0);
2467 }
2468
2469 static void diff_summary(struct diff_filepair *p)
2470 {
2471         switch(p->status) {
2472         case DIFF_STATUS_DELETED:
2473                 show_file_mode_name("delete", p->one);
2474                 break;
2475         case DIFF_STATUS_ADDED:
2476                 show_file_mode_name("create", p->two);
2477                 break;
2478         case DIFF_STATUS_COPIED:
2479                 show_rename_copy("copy", p);
2480                 break;
2481         case DIFF_STATUS_RENAMED:
2482                 show_rename_copy("rename", p);
2483                 break;
2484         default:
2485                 if (p->score) {
2486                         char *name = quote_one(p->two->path);
2487                         printf(" rewrite %s (%d%%)\n", name,
2488                                 (int)(0.5 + p->score * 100.0/MAX_SCORE));
2489                         free(name);
2490                         show_mode_change(p, 0);
2491                 } else  show_mode_change(p, 1);
2492                 break;
2493         }
2494 }
2495
2496 struct patch_id_t {
2497         struct xdiff_emit_state xm;
2498         SHA_CTX *ctx;
2499         int patchlen;
2500 };
2501
2502 static int remove_space(char *line, int len)
2503 {
2504         int i;
2505         char *dst = line;
2506         unsigned char c;
2507
2508         for (i = 0; i < len; i++)
2509                 if (!isspace((c = line[i])))
2510                         *dst++ = c;
2511
2512         return dst - line;
2513 }
2514
2515 static void patch_id_consume(void *priv, char *line, unsigned long len)
2516 {
2517         struct patch_id_t *data = priv;
2518         int new_len;
2519
2520         /* Ignore line numbers when computing the SHA1 of the patch */
2521         if (!strncmp(line, "@@ -", 4))
2522                 return;
2523
2524         new_len = remove_space(line, len);
2525
2526         SHA1_Update(data->ctx, line, new_len);
2527         data->patchlen += new_len;
2528 }
2529
2530 /* returns 0 upon success, and writes result into sha1 */
2531 static int diff_get_patch_id(struct diff_options *options, unsigned char *sha1)
2532 {
2533         struct diff_queue_struct *q = &diff_queued_diff;
2534         int i;
2535         SHA_CTX ctx;
2536         struct patch_id_t data;
2537         char buffer[PATH_MAX * 4 + 20];
2538
2539         SHA1_Init(&ctx);
2540         memset(&data, 0, sizeof(struct patch_id_t));
2541         data.ctx = &ctx;
2542         data.xm.consume = patch_id_consume;
2543
2544         for (i = 0; i < q->nr; i++) {
2545                 xpparam_t xpp;
2546                 xdemitconf_t xecfg;
2547                 xdemitcb_t ecb;
2548                 mmfile_t mf1, mf2;
2549                 struct diff_filepair *p = q->queue[i];
2550                 int len1, len2;
2551
2552                 if (p->status == 0)
2553                         return error("internal diff status error");
2554                 if (p->status == DIFF_STATUS_UNKNOWN)
2555                         continue;
2556                 if (diff_unmodified_pair(p))
2557                         continue;
2558                 if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
2559                     (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
2560                         continue;
2561                 if (DIFF_PAIR_UNMERGED(p))
2562                         continue;
2563
2564                 diff_fill_sha1_info(p->one);
2565                 diff_fill_sha1_info(p->two);
2566                 if (fill_mmfile(&mf1, p->one) < 0 ||
2567                                 fill_mmfile(&mf2, p->two) < 0)
2568                         return error("unable to read files to diff");
2569
2570                 /* Maybe hash p->two? into the patch id? */
2571                 if (mmfile_is_binary(&mf2))
2572                         continue;
2573
2574                 len1 = remove_space(p->one->path, strlen(p->one->path));
2575                 len2 = remove_space(p->two->path, strlen(p->two->path));
2576                 if (p->one->mode == 0)
2577                         len1 = snprintf(buffer, sizeof(buffer),
2578                                         "diff--gita/%.*sb/%.*s"
2579                                         "newfilemode%06o"
2580                                         "---/dev/null"
2581                                         "+++b/%.*s",
2582                                         len1, p->one->path,
2583                                         len2, p->two->path,
2584                                         p->two->mode,
2585                                         len2, p->two->path);
2586                 else if (p->two->mode == 0)
2587                         len1 = snprintf(buffer, sizeof(buffer),
2588                                         "diff--gita/%.*sb/%.*s"
2589                                         "deletedfilemode%06o"
2590                                         "---a/%.*s"
2591                                         "+++/dev/null",
2592                                         len1, p->one->path,
2593                                         len2, p->two->path,
2594                                         p->one->mode,
2595                                         len1, p->one->path);
2596                 else
2597                         len1 = snprintf(buffer, sizeof(buffer),
2598                                         "diff--gita/%.*sb/%.*s"
2599                                         "---a/%.*s"
2600                                         "+++b/%.*s",
2601                                         len1, p->one->path,
2602                                         len2, p->two->path,
2603                                         len1, p->one->path,
2604                                         len2, p->two->path);
2605                 SHA1_Update(&ctx, buffer, len1);
2606
2607                 xpp.flags = XDF_NEED_MINIMAL;
2608                 xecfg.ctxlen = 3;
2609                 xecfg.flags = XDL_EMIT_FUNCNAMES;
2610                 ecb.outf = xdiff_outf;
2611                 ecb.priv = &data;
2612                 xdl_diff(&mf1, &mf2, &xpp, &xecfg, &ecb);
2613         }
2614
2615         SHA1_Final(sha1, &ctx);
2616         return 0;
2617 }
2618
2619 int diff_flush_patch_id(struct diff_options *options, unsigned char *sha1)
2620 {
2621         struct diff_queue_struct *q = &diff_queued_diff;
2622         int i;
2623         int result = diff_get_patch_id(options, sha1);
2624
2625         for (i = 0; i < q->nr; i++)
2626                 diff_free_filepair(q->queue[i]);
2627
2628         free(q->queue);
2629         q->queue = NULL;
2630         q->nr = q->alloc = 0;
2631
2632         return result;
2633 }
2634
2635 static int is_summary_empty(const struct diff_queue_struct *q)
2636 {
2637         int i;
2638
2639         for (i = 0; i < q->nr; i++) {
2640                 const struct diff_filepair *p = q->queue[i];
2641
2642                 switch (p->status) {
2643                 case DIFF_STATUS_DELETED:
2644                 case DIFF_STATUS_ADDED:
2645                 case DIFF_STATUS_COPIED:
2646                 case DIFF_STATUS_RENAMED:
2647                         return 0;
2648                 default:
2649                         if (p->score)
2650                                 return 0;
2651                         if (p->one->mode && p->two->mode &&
2652                             p->one->mode != p->two->mode)
2653                                 return 0;
2654                         break;
2655                 }
2656         }
2657         return 1;
2658 }
2659
2660 void diff_flush(struct diff_options *options)
2661 {
2662         struct diff_queue_struct *q = &diff_queued_diff;
2663         int i, output_format = options->output_format;
2664         int separator = 0;
2665
2666         /*
2667          * Order: raw, stat, summary, patch
2668          * or:    name/name-status/checkdiff (other bits clear)
2669          */
2670         if (!q->nr)
2671                 goto free_queue;
2672
2673         if (output_format & (DIFF_FORMAT_RAW |
2674                              DIFF_FORMAT_NAME |
2675                              DIFF_FORMAT_NAME_STATUS |
2676                              DIFF_FORMAT_CHECKDIFF)) {
2677                 for (i = 0; i < q->nr; i++) {
2678                         struct diff_filepair *p = q->queue[i];
2679                         if (check_pair_status(p))
2680                                 flush_one_pair(p, options);
2681                 }
2682                 separator++;
2683         }
2684
2685         if (output_format & (DIFF_FORMAT_DIFFSTAT|DIFF_FORMAT_SHORTSTAT|DIFF_FORMAT_NUMSTAT)) {
2686                 struct diffstat_t diffstat;
2687
2688                 memset(&diffstat, 0, sizeof(struct diffstat_t));
2689                 diffstat.xm.consume = diffstat_consume;
2690                 for (i = 0; i < q->nr; i++) {
2691                         struct diff_filepair *p = q->queue[i];
2692                         if (check_pair_status(p))
2693                                 diff_flush_stat(p, options, &diffstat);
2694                 }
2695                 if (output_format & DIFF_FORMAT_NUMSTAT)
2696                         show_numstat(&diffstat, options);
2697                 if (output_format & DIFF_FORMAT_DIFFSTAT)
2698                         show_stats(&diffstat, options);
2699                 else if (output_format & DIFF_FORMAT_SHORTSTAT)
2700                         show_shortstats(&diffstat);
2701                 separator++;
2702         }
2703
2704         if (output_format & DIFF_FORMAT_SUMMARY && !is_summary_empty(q)) {
2705                 for (i = 0; i < q->nr; i++)
2706                         diff_summary(q->queue[i]);
2707                 separator++;
2708         }
2709
2710         if (output_format & DIFF_FORMAT_PATCH) {
2711                 if (separator) {
2712                         if (options->stat_sep) {
2713                                 /* attach patch instead of inline */
2714                                 fputs(options->stat_sep, stdout);
2715                         } else {
2716                                 putchar(options->line_termination);
2717                         }
2718                 }
2719
2720                 for (i = 0; i < q->nr; i++) {
2721                         struct diff_filepair *p = q->queue[i];
2722                         if (check_pair_status(p))
2723                                 diff_flush_patch(p, options);
2724                 }
2725         }
2726
2727         if (output_format & DIFF_FORMAT_CALLBACK)
2728                 options->format_callback(q, options, options->format_callback_data);
2729
2730         for (i = 0; i < q->nr; i++)
2731                 diff_free_filepair(q->queue[i]);
2732 free_queue:
2733         free(q->queue);
2734         q->queue = NULL;
2735         q->nr = q->alloc = 0;
2736 }
2737
2738 static void diffcore_apply_filter(const char *filter)
2739 {
2740         int i;
2741         struct diff_queue_struct *q = &diff_queued_diff;
2742         struct diff_queue_struct outq;
2743         outq.queue = NULL;
2744         outq.nr = outq.alloc = 0;
2745
2746         if (!filter)
2747                 return;
2748
2749         if (strchr(filter, DIFF_STATUS_FILTER_AON)) {
2750                 int found;
2751                 for (i = found = 0; !found && i < q->nr; i++) {
2752                         struct diff_filepair *p = q->queue[i];
2753                         if (((p->status == DIFF_STATUS_MODIFIED) &&
2754                              ((p->score &&
2755                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
2756                               (!p->score &&
2757                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
2758                             ((p->status != DIFF_STATUS_MODIFIED) &&
2759                              strchr(filter, p->status)))
2760                                 found++;
2761                 }
2762                 if (found)
2763                         return;
2764
2765                 /* otherwise we will clear the whole queue
2766                  * by copying the empty outq at the end of this
2767                  * function, but first clear the current entries
2768                  * in the queue.
2769                  */
2770                 for (i = 0; i < q->nr; i++)
2771                         diff_free_filepair(q->queue[i]);
2772         }
2773         else {
2774                 /* Only the matching ones */
2775                 for (i = 0; i < q->nr; i++) {
2776                         struct diff_filepair *p = q->queue[i];
2777
2778                         if (((p->status == DIFF_STATUS_MODIFIED) &&
2779                              ((p->score &&
2780                                strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
2781                               (!p->score &&
2782                                strchr(filter, DIFF_STATUS_MODIFIED)))) ||
2783                             ((p->status != DIFF_STATUS_MODIFIED) &&
2784                              strchr(filter, p->status)))
2785                                 diff_q(&outq, p);
2786                         else
2787                                 diff_free_filepair(p);
2788                 }
2789         }
2790         free(q->queue);
2791         *q = outq;
2792 }
2793
2794 void diffcore_std(struct diff_options *options)
2795 {
2796         if (options->break_opt != -1)
2797                 diffcore_break(options->break_opt);
2798         if (options->detect_rename)
2799                 diffcore_rename(options);
2800         if (options->break_opt != -1)
2801                 diffcore_merge_broken();
2802         if (options->pickaxe)
2803                 diffcore_pickaxe(options->pickaxe, options->pickaxe_opts);
2804         if (options->orderfile)
2805                 diffcore_order(options->orderfile);
2806         diff_resolve_rename_copy();
2807         diffcore_apply_filter(options->filter);
2808 }
2809
2810
2811 void diffcore_std_no_resolve(struct diff_options *options)
2812 {
2813         if (options->pickaxe)
2814                 diffcore_pickaxe(options->pickaxe, options->pickaxe_opts);
2815         if (options->orderfile)
2816                 diffcore_order(options->orderfile);
2817         diffcore_apply_filter(options->filter);
2818 }
2819
2820 void diff_addremove(struct diff_options *options,
2821                     int addremove, unsigned mode,
2822                     const unsigned char *sha1,
2823                     const char *base, const char *path)
2824 {
2825         char concatpath[PATH_MAX];
2826         struct diff_filespec *one, *two;
2827
2828         /* This may look odd, but it is a preparation for
2829          * feeding "there are unchanged files which should
2830          * not produce diffs, but when you are doing copy
2831          * detection you would need them, so here they are"
2832          * entries to the diff-core.  They will be prefixed
2833          * with something like '=' or '*' (I haven't decided
2834          * which but should not make any difference).
2835          * Feeding the same new and old to diff_change()
2836          * also has the same effect.
2837          * Before the final output happens, they are pruned after
2838          * merged into rename/copy pairs as appropriate.
2839          */
2840         if (options->reverse_diff)
2841                 addremove = (addremove == '+' ? '-' :
2842                              addremove == '-' ? '+' : addremove);
2843
2844         if (!path) path = "";
2845         sprintf(concatpath, "%s%s", base, path);
2846         one = alloc_filespec(concatpath);
2847         two = alloc_filespec(concatpath);
2848
2849         if (addremove != '+')
2850                 fill_filespec(one, sha1, mode);
2851         if (addremove != '-')
2852                 fill_filespec(two, sha1, mode);
2853
2854         diff_queue(&diff_queued_diff, one, two);
2855 }
2856
2857 void diff_change(struct diff_options *options,
2858                  unsigned old_mode, unsigned new_mode,
2859                  const unsigned char *old_sha1,
2860                  const unsigned char *new_sha1,
2861                  const char *base, const char *path)
2862 {
2863         char concatpath[PATH_MAX];
2864         struct diff_filespec *one, *two;
2865
2866         if (options->reverse_diff) {
2867                 unsigned tmp;
2868                 const unsigned char *tmp_c;
2869                 tmp = old_mode; old_mode = new_mode; new_mode = tmp;
2870                 tmp_c = old_sha1; old_sha1 = new_sha1; new_sha1 = tmp_c;
2871         }
2872         if (!path) path = "";
2873         sprintf(concatpath, "%s%s", base, path);
2874         one = alloc_filespec(concatpath);
2875         two = alloc_filespec(concatpath);
2876         fill_filespec(one, old_sha1, old_mode);
2877         fill_filespec(two, new_sha1, new_mode);
2878
2879         diff_queue(&diff_queued_diff, one, two);
2880 }
2881
2882 void diff_unmerge(struct diff_options *options,
2883                   const char *path,
2884                   unsigned mode, const unsigned char *sha1)
2885 {
2886         struct diff_filespec *one, *two;
2887         one = alloc_filespec(path);
2888         two = alloc_filespec(path);
2889         fill_filespec(one, sha1, mode);
2890         diff_queue(&diff_queued_diff, one, two)->is_unmerged = 1;
2891 }