diff: refactor the word-diff setup from builtin_diff_cmd

Quite a chunk of builtin_diff_cmd deals with word-diff setup, defaults
and such.  This makes the function a bit hard to read, but is also
asymmetric because the corresponding teardown lives in free_diff_words_data
already.

Refactor into a new function init_diff_words_data.  For simplicity,
also shuffle around some functions it depends on.

Signed-off-by: Thomas Rast <trast@student.ethz.ch>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/diff.c b/diff.c
index 5388ded2140d9d4268fbda702603902bf4530981..526f1980596887dff99b1236ce39a47b6bdb7215 100644 (file)
--- a/diff.c
+++ b/diff.c
@@ -987,6 +987,67 @@ static void diff_words_flush(struct emit_callback *ecbdata)
                diff_words_show(ecbdata->diff_words);
 }
 
+static void diff_filespec_load_driver(struct diff_filespec *one)
+{
+       /* Use already-loaded driver */
+       if (one->driver)
+               return;
+
+       if (S_ISREG(one->mode))
+               one->driver = userdiff_find_by_path(one->path);
+
+       /* Fallback to default settings */
+       if (!one->driver)
+               one->driver = userdiff_find_by_name("default");
+}
+
+static const char *userdiff_word_regex(struct diff_filespec *one)
+{
+       diff_filespec_load_driver(one);
+       return one->driver->word_regex;
+}
+
+static void init_diff_words_data(struct emit_callback *ecbdata,
+                                struct diff_options *o,
+                                struct diff_filespec *one,
+                                struct diff_filespec *two)
+{
+       int i;
+
+       ecbdata->diff_words =
+               xcalloc(1, sizeof(struct diff_words_data));
+       ecbdata->diff_words->type = o->word_diff;
+       ecbdata->diff_words->opt = o;
+       if (!o->word_regex)
+               o->word_regex = userdiff_word_regex(one);
+       if (!o->word_regex)
+               o->word_regex = userdiff_word_regex(two);
+       if (!o->word_regex)
+               o->word_regex = diff_word_regex_cfg;
+       if (o->word_regex) {
+               ecbdata->diff_words->word_regex = (regex_t *)
+                       xmalloc(sizeof(regex_t));
+               if (regcomp(ecbdata->diff_words->word_regex,
+                           o->word_regex,
+                           REG_EXTENDED | REG_NEWLINE))
+                       die ("Invalid regular expression: %s",
+                            o->word_regex);
+       }
+       for (i = 0; i < ARRAY_SIZE(diff_words_styles); i++) {
+               if (o->word_diff == diff_words_styles[i].type) {
+                       ecbdata->diff_words->style =
+                               &diff_words_styles[i];
+                       break;
+               }
+       }
+       if (want_color(o->use_color)) {
+               struct diff_words_style *st = ecbdata->diff_words->style;
+               st->old.color = diff_get_color_opt(o, DIFF_FILE_OLD);
+               st->new.color = diff_get_color_opt(o, DIFF_FILE_NEW);
+               st->ctx.color = diff_get_color_opt(o, DIFF_PLAIN);
+       }
+}
+
 static void free_diff_words_data(struct emit_callback *ecbdata)
 {
        if (ecbdata->diff_words) {
@@ -2016,20 +2077,6 @@ static void emit_binary_diff(FILE *file, mmfile_t *one, mmfile_t *two, char *pre
        emit_binary_diff_body(file, two, one, prefix);
 }
 
-static void diff_filespec_load_driver(struct diff_filespec *one)
-{
-       /* Use already-loaded driver */
-       if (one->driver)
-               return;
-
-       if (S_ISREG(one->mode))
-               one->driver = userdiff_find_by_path(one->path);
-
-       /* Fallback to default settings */
-       if (!one->driver)
-               one->driver = userdiff_find_by_name("default");
-}
-
 int diff_filespec_is_binary(struct diff_filespec *one)
 {
        if (one->is_binary == -1) {
@@ -2055,12 +2102,6 @@ static const struct userdiff_funcname *diff_funcname_pattern(struct diff_filespe
        return one->driver->funcname.pattern ? &one->driver->funcname : NULL;
 }
 
-static const char *userdiff_word_regex(struct diff_filespec *one)
-{
-       diff_filespec_load_driver(one);
-       return one->driver->word_regex;
-}
-
 void diff_set_mnemonic_prefix(struct diff_options *options, const char *a, const char *b)
 {
        if (!options->a_prefix)
@@ -2247,42 +2288,8 @@ static void builtin_diff(const char *name_a,
                        xecfg.ctxlen = strtoul(diffopts + 10, NULL, 10);
                else if (!prefixcmp(diffopts, "-u"))
                        xecfg.ctxlen = strtoul(diffopts + 2, NULL, 10);
-               if (o->word_diff) {
-                       int i;
-
-                       ecbdata.diff_words =
-                               xcalloc(1, sizeof(struct diff_words_data));
-                       ecbdata.diff_words->type = o->word_diff;
-                       ecbdata.diff_words->opt = o;
-                       if (!o->word_regex)
-                               o->word_regex = userdiff_word_regex(one);
-                       if (!o->word_regex)
-                               o->word_regex = userdiff_word_regex(two);
-                       if (!o->word_regex)
-                               o->word_regex = diff_word_regex_cfg;
-                       if (o->word_regex) {
-                               ecbdata.diff_words->word_regex = (regex_t *)
-                                       xmalloc(sizeof(regex_t));
-                               if (regcomp(ecbdata.diff_words->word_regex,
-                                               o->word_regex,
-                                               REG_EXTENDED | REG_NEWLINE))
-                                       die ("Invalid regular expression: %s",
-                                                       o->word_regex);
-                       }
-                       for (i = 0; i < ARRAY_SIZE(diff_words_styles); i++) {
-                               if (o->word_diff == diff_words_styles[i].type) {
-                                       ecbdata.diff_words->style =
-                                               &diff_words_styles[i];
-                                       break;
-                               }
-                       }
-                       if (want_color(o->use_color)) {
-                               struct diff_words_style *st = ecbdata.diff_words->style;
-                               st->old.color = diff_get_color_opt(o, DIFF_FILE_OLD);
-                               st->new.color = diff_get_color_opt(o, DIFF_FILE_NEW);
-                               st->ctx.color = diff_get_color_opt(o, DIFF_PLAIN);
-                       }
-               }
+               if (o->word_diff)
+                       init_diff_words_data(&ecbdata, o, one, two);
                xdi_diff_outf(&mf1, &mf2, fn_out_consume, &ecbdata,
                              &xpp, &xecfg);
                if (o->word_diff)