git-format-patch should show the correct version

[git.git] / diff.c

diff --git a/diff.c b/diff.c
index 2e0797b..c815918 100644 (file)
--- a/diff.c
+++ b/diff.c
@@ -723,11 +723,13 @@ static void run_diff(struct diff_filepair *p, struct diff_options *o)
 
        if (memcmp(one->sha1, two->sha1, 20)) {
                char one_sha1[41];
-               const char *index_fmt = o->full_index ? "index %s..%s" : "index %.7s..%.7s";
+               int abbrev = o->full_index ? 40 : DIFF_DEFAULT_INDEX_ABBREV;
                memcpy(one_sha1, sha1_to_hex(one->sha1), 41);
 
                len += snprintf(msg + len, sizeof(msg) - len,
-                               index_fmt, one_sha1, sha1_to_hex(two->sha1));
+                               "index %.*s..%.*s",
+                               abbrev, one_sha1, abbrev,
+                               sha1_to_hex(two->sha1));
                if (one->mode == two->mode)
                        len += snprintf(msg + len, sizeof(msg) - len,
                                        " %06o", one->mode);
@@ -791,6 +793,8 @@ int diff_setup_done(struct diff_options *options)
        }
        if (options->setup & DIFF_SETUP_USE_SIZE_CACHE)
                use_size_cache = 1;
+       if (options->abbrev <= 0 || 40 < options->abbrev)
+               options->abbrev = 40; /* full */
 
        return 0;
 }
@@ -841,6 +845,10 @@ int diff_opt_parse(struct diff_options *options, const char **av, int ac)
        }
        else if (!strcmp(arg, "--find-copies-harder"))
                options->find_copies_harder = 1;
+       else if (!strcmp(arg, "--abbrev"))
+               options->abbrev = DIFF_DEFAULT_ABBREV;
+       else if (!strncmp(arg, "--abbrev=", 9))
+               options->abbrev = strtoul(arg + 9, NULL, 10);
        else
                return 0;
        return 1;
@@ -947,14 +955,49 @@ void diff_free_filepair(struct diff_filepair *p)
        free(p);
 }
 
+/* This is different from find_unique_abbrev() in that
+ * it needs to deal with 0{40} SHA1.
+ */
+const char *diff_unique_abbrev(const unsigned char *sha1, int len)
+{
+       int abblen;
+       const char *abbrev;
+       if (len == 40)
+               return sha1_to_hex(sha1);
+
+       abbrev = find_unique_abbrev(sha1, len);
+       if (!abbrev) {
+               if (!memcmp(sha1, null_sha1, 20)) {
+                       char *buf = sha1_to_hex(null_sha1);
+                       if (len < 37)
+                               strcpy(buf + len, "...");
+                       return buf;
+               }
+               else 
+                       return sha1_to_hex(sha1);
+       }
+       abblen = strlen(abbrev);
+       if (abblen < 37) {
+               static char hex[41];
+               if (len < abblen && abblen <= len + 2)
+                       sprintf(hex, "%s%.*s", abbrev, len+3-abblen, "..");
+               else
+                       sprintf(hex, "%s...", abbrev);
+               return hex;
+       }
+       return sha1_to_hex(sha1);
+}
+
 static void diff_flush_raw(struct diff_filepair *p,
                           int line_termination,
                           int inter_name_termination,
-                          int output_format)
+                          struct diff_options *options)
 {
        int two_paths;
        char status[10];
+       int abbrev = options->abbrev;
        const char *path_one, *path_two;
+       int output_format = options->output_format;
 
        path_one = p->one->path;
        path_two = p->two->path;
@@ -985,8 +1028,10 @@ static void diff_flush_raw(struct diff_filepair *p,
        }
        if (output_format != DIFF_FORMAT_NAME_STATUS) {
                printf(":%06o %06o %s ",
-                      p->one->mode, p->two->mode, sha1_to_hex(p->one->sha1));
-               printf("%s ", sha1_to_hex(p->two->sha1));
+                      p->one->mode, p->two->mode,
+                      diff_unique_abbrev(p->one->sha1, abbrev));
+               printf("%s ",
+                      diff_unique_abbrev(p->two->sha1, abbrev));
        }
        printf("%s%c%s", status, inter_name_termination, path_one);
        if (two_paths)
@@ -1194,7 +1239,7 @@ void diff_flush(struct diff_options *options)
                case DIFF_FORMAT_NAME_STATUS:
                        diff_flush_raw(p, line_termination,
                                       inter_name_termination,
-                                      diff_output_format);
+                                      options);
                        break;
                case DIFF_FORMAT_NAME:
                        diff_flush_name(p,