diff --no-index: use strbuf for temporary pathnames

Instead of using limited-length buffers and risking of pathname
truncation, we should be taking advantage of strbuf API nowadays.

Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/diff-no-index.c b/diff-no-index.c
index 5cd3ff5848c1ad913c7802a157c61df42a0e9269..b44473e3c1fd5c2bdc4dce3af7aabc86fd37eb08 100644 (file)
--- a/diff-no-index.c
+++ b/diff-no-index.c
@@ -52,7 +52,7 @@ static int get_mode(const char *path, int *mode)
 }
 
 static int queue_diff(struct diff_options *o,
-               const char *name1, const char *name2)
+                     const char *name1, const char *name2)
 {
        int mode1 = 0, mode2 = 0;
 
@@ -63,10 +63,11 @@ static int queue_diff(struct diff_options *o,
                return error("file/directory conflict: %s, %s", name1, name2);
 
        if (S_ISDIR(mode1) || S_ISDIR(mode2)) {
-               char buffer1[PATH_MAX], buffer2[PATH_MAX];
+               struct strbuf buffer1 = STRBUF_INIT;
+               struct strbuf buffer2 = STRBUF_INIT;
                struct string_list p1 = STRING_LIST_INIT_DUP;
                struct string_list p2 = STRING_LIST_INIT_DUP;
-               int len1 = 0, len2 = 0, i1, i2, ret = 0;
+               int i1, i2, ret = 0;
 
                if (name1 && read_directory(name1, &p1))
                        return -1;
@@ -76,19 +77,15 @@ static int queue_diff(struct diff_options *o,
                }
 
                if (name1) {
-                       len1 = strlen(name1);
-                       if (len1 > 0 && name1[len1 - 1] == '/')
-                               len1--;
-                       memcpy(buffer1, name1, len1);
-                       buffer1[len1++] = '/';
+                       strbuf_addstr(&buffer1, name1);
+                       if (buffer1.len && buffer1.buf[buffer1.len - 1] != '/')
+                               strbuf_addch(&buffer1, '/');
                }
 
                if (name2) {
-                       len2 = strlen(name2);
-                       if (len2 > 0 && name2[len2 - 1] == '/')
-                               len2--;
-                       memcpy(buffer2, name2, len2);
-                       buffer2[len2++] = '/';
+                       strbuf_addstr(&buffer2, name2);
+                       if (buffer2.len && buffer2.buf[buffer2.len - 1] != '/')
+                               strbuf_addch(&buffer2, '/');
                }
 
                for (i1 = i2 = 0; !ret && (i1 < p1.nr || i2 < p2.nr); ) {
@@ -100,31 +97,28 @@ static int queue_diff(struct diff_options *o,
                        else if (i2 == p2.nr)
                                comp = -1;
                        else
-                               comp = strcmp(p1.items[i1].string,
-                                       p2.items[i2].string);
+                               comp = strcmp(p1.items[i1].string, p2.items[i2].string);
 
                        if (comp > 0)
                                n1 = NULL;
                        else {
-                               n1 = buffer1;
-                               strncpy(buffer1 + len1, p1.items[i1++].string,
-                                               PATH_MAX - len1);
-                               buffer1[PATH_MAX-1] = 0;
+                               strbuf_addstr(&buffer1, p1.items[i1++].string);
+                               n1 = buffer1.buf;
                        }
 
                        if (comp < 0)
                                n2 = NULL;
                        else {
-                               n2 = buffer2;
-                               strncpy(buffer2 + len2, p2.items[i2++].string,
-                                               PATH_MAX - len2);
-                               buffer2[PATH_MAX-1] = 0;
+                               strbuf_addstr(&buffer2, p2.items[i2++].string);
+                               n2 = buffer2.buf;
                        }
 
                        ret = queue_diff(o, n1, n2);
                }
                string_list_clear(&p1, 0);
                string_list_clear(&p2, 0);
+               strbuf_reset(&buffer1);
+               strbuf_reset(&buffer2);
 
                return ret;
        } else {