Add git-config-set, a simple helper for scripts to set config variables
[git.git] / diff.c
diff --git a/diff.c b/diff.c
index 9bded28..0391e8c 100644 (file)
--- a/diff.c
+++ b/diff.c
 #include "diffcore.h"
 
 static const char *diff_opts = "-pu";
-static unsigned char null_sha1[20] = { 0, };
 
 static int use_size_cache;
 
+int diff_rename_limit_default = -1;
+
+static char *quote_one(const char *str)
+{
+       int needlen;
+       char *xp;
+
+       if (!str)
+               return NULL;
+       needlen = quote_c_style(str, NULL, NULL, 0);
+       if (!needlen)
+               return strdup(str);
+       xp = xmalloc(needlen + 1);
+       quote_c_style(str, xp, NULL, 0);
+       return xp;
+}
+
+static char *quote_two(const char *one, const char *two)
+{
+       int need_one = quote_c_style(one, NULL, NULL, 1);
+       int need_two = quote_c_style(two, NULL, NULL, 1);
+       char *xp;
+
+       if (need_one + need_two) {
+               if (!need_one) need_one = strlen(one);
+               if (!need_two) need_one = strlen(two);
+
+               xp = xmalloc(need_one + need_two + 3);
+               xp[0] = '"';
+               quote_c_style(one, xp + 1, NULL, 1);
+               quote_c_style(two, xp + need_one + 1, NULL, 1);
+               strcpy(xp + need_one + need_two + 1, "\"");
+               return xp;
+       }
+       need_one = strlen(one);
+       need_two = strlen(two);
+       xp = xmalloc(need_one + need_two + 1);
+       strcpy(xp, one);
+       strcpy(xp + need_one, two);
+       return xp;
+}
+
 static const char *external_diff(void)
 {
        static const char *external_diff_cmd = NULL;
@@ -134,55 +175,52 @@ static void builtin_diff(const char *name_a,
                         int complete_rewrite)
 {
        int i, next_at, cmd_size;
-       const char *const diff_cmd = "diff -L%s%s -L%s%s";
-       const char *const diff_arg  = "%s %s||:"; /* "||:" is to return 0 */
+       const char *const diff_cmd = "diff -L%s -L%s";
+       const char *const diff_arg  = "-- %s %s||:"; /* "||:" is to return 0 */
        const char *input_name_sq[2];
-       const char *path0[2];
-       const char *path1[2];
-       const char *name_sq[2];
+       const char *label_path[2];
        char *cmd;
 
-       name_sq[0] = sq_quote(name_a);
-       name_sq[1] = sq_quote(name_b);
-
-       /* diff_cmd and diff_arg have 6 %s in total which makes
-        * the sum of these strings 12 bytes larger than required.
+       /* diff_cmd and diff_arg have 4 %s in total which makes
+        * the sum of these strings 8 bytes larger than required.
         * we use 2 spaces around diff-opts, and we need to count
-        * terminating NUL, so we subtract 9 here.
+        * terminating NUL; we used to subtract 5 here, but we do not
+        * care about small leaks in this subprocess that is about
+        * to exec "diff" anymore.
         */
-       cmd_size = (strlen(diff_cmd) + strlen(diff_opts) +
-                       strlen(diff_arg) - 9);
+       cmd_size = (strlen(diff_cmd) + strlen(diff_opts) + strlen(diff_arg)
+                   + 128);
+
        for (i = 0; i < 2; i++) {
                input_name_sq[i] = sq_quote(temp[i].name);
-               if (!strcmp(temp[i].name, "/dev/null")) {
-                       path0[i] = "/dev/null";
-                       path1[i] = "";
-               } else {
-                       path0[i] = i ? "b/" : "a/";
-                       path1[i] = name_sq[i];
-               }
-               cmd_size += (strlen(path0[i]) + strlen(path1[i]) +
-                            strlen(input_name_sq[i]));
+               if (!strcmp(temp[i].name, "/dev/null"))
+                       label_path[i] = "/dev/null";
+               else if (!i)
+                       label_path[i] = sq_quote(quote_two("a/", name_a));
+               else
+                       label_path[i] = sq_quote(quote_two("b/", name_b));
+               cmd_size += (strlen(label_path[i]) + strlen(input_name_sq[i]));
        }
 
        cmd = xmalloc(cmd_size);
 
        next_at = 0;
        next_at += snprintf(cmd+next_at, cmd_size-next_at,
-                           diff_cmd,
-                           path0[0], path1[0], path0[1], path1[1]);
+                           diff_cmd, label_path[0], label_path[1]);
        next_at += snprintf(cmd+next_at, cmd_size-next_at,
                            " %s ", diff_opts);
        next_at += snprintf(cmd+next_at, cmd_size-next_at,
                            diff_arg, input_name_sq[0], input_name_sq[1]);
 
-       printf("diff --git a/%s b/%s\n", name_a, name_b);
-       if (!path1[0][0]) {
+       printf("diff --git %s %s\n",
+              quote_two("a/", name_a), quote_two("b/", name_b));
+       if (label_path[0][0] == '/') {
+               /* dev/null */
                printf("new file mode %s\n", temp[1].mode);
                if (xfrm_msg && xfrm_msg[0])
                        puts(xfrm_msg);
        }
-       else if (!path1[1][0]) {
+       else if (label_path[1][0] == '/') {
                printf("deleted file mode %s\n", temp[0].mode);
                if (xfrm_msg && xfrm_msg[0])
                        puts(xfrm_msg);
@@ -414,7 +452,7 @@ void diff_free_filespec_data(struct diff_filespec *s)
 static void prep_temp_blob(struct diff_tempfile *temp,
                           void *blob,
                           unsigned long size,
-                          unsigned char *sha1,
+                          const unsigned char *sha1,
                           int mode)
 {
        int fd;
@@ -597,15 +635,32 @@ static void run_external_diff(const char *pgm,
        remove_tempfile();
 }
 
-static void run_diff(struct diff_filepair *p)
+static void diff_fill_sha1_info(struct diff_filespec *one)
+{
+       if (DIFF_FILE_VALID(one)) {
+               if (!one->sha1_valid) {
+                       struct stat st;
+                       if (stat(one->path, &st) < 0)
+                               die("stat %s", one->path);
+                       if (index_path(one->sha1, one->path, &st, 0))
+                               die("cannot hash %s\n", one->path);
+               }
+       }
+       else
+               memset(one->sha1, 0, 20);
+}
+
+static void run_diff(struct diff_filepair *p, struct diff_options *o)
 {
        const char *pgm = external_diff();
-       char msg_[PATH_MAX*2+200], *xfrm_msg;
+       char msg[PATH_MAX*2+300], *xfrm_msg;
        struct diff_filespec *one;
        struct diff_filespec *two;
        const char *name;
        const char *other;
+       char *name_munged, *other_munged;
        int complete_rewrite = 0;
+       int len;
 
        if (DIFF_PAIR_UNMERGED(p)) {
                /* unmerged */
@@ -616,40 +671,63 @@ static void run_diff(struct diff_filepair *p)
 
        name = p->one->path;
        other = (strcmp(name, p->two->path) ? p->two->path : NULL);
+       name_munged = quote_one(name);
+       other_munged = quote_one(other);
        one = p->one; two = p->two;
+
+       diff_fill_sha1_info(one);
+       diff_fill_sha1_info(two);
+
+       len = 0;
        switch (p->status) {
        case DIFF_STATUS_COPIED:
-               sprintf(msg_,
-                       "similarity index %d%%\n"
-                       "copy from %s\n"
-                       "copy to %s",
-                       (int)(0.5 + p->score * 100.0/MAX_SCORE),
-                       name, other);
-               xfrm_msg = msg_;
+               len += snprintf(msg + len, sizeof(msg) - len,
+                               "similarity index %d%%\n"
+                               "copy from %s\n"
+                               "copy to %s\n",
+                               (int)(0.5 + p->score * 100.0/MAX_SCORE),
+                               name_munged, other_munged);
                break;
        case DIFF_STATUS_RENAMED:
-               sprintf(msg_,
-                       "similarity index %d%%\n"
-                       "rename from %s\n"
-                       "rename to %s",
-                       (int)(0.5 + p->score * 100.0/MAX_SCORE),
-                       name, other);
-               xfrm_msg = msg_;
+               len += snprintf(msg + len, sizeof(msg) - len,
+                               "similarity index %d%%\n"
+                               "rename from %s\n"
+                               "rename to %s\n",
+                               (int)(0.5 + p->score * 100.0/MAX_SCORE),
+                               name_munged, other_munged);
                break;
        case DIFF_STATUS_MODIFIED:
                if (p->score) {
-                       sprintf(msg_,
-                               "dissimilarity index %d%%",
-                               (int)(0.5 + p->score * 100.0/MAX_SCORE));
-                       xfrm_msg = msg_;
+                       len += snprintf(msg + len, sizeof(msg) - len,
+                                       "dissimilarity index %d%%\n",
+                                       (int)(0.5 + p->score *
+                                             100.0/MAX_SCORE));
                        complete_rewrite = 1;
                        break;
                }
                /* fallthru */
        default:
-               xfrm_msg = NULL;
+               /* nothing */
+               ;
        }
 
+       if (memcmp(one->sha1, two->sha1, 20)) {
+               char one_sha1[41];
+               const char *index_fmt = o->full_index ? "index %s..%s" : "index %.7s..%.7s";
+               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));
+               if (one->mode == two->mode)
+                       len += snprintf(msg + len, sizeof(msg) - len,
+                                       " %06o", one->mode);
+               len += snprintf(msg + len, sizeof(msg) - len, "\n");
+       }
+
+       if (len)
+               msg[--len] = 0;
+       xfrm_msg = len ? msg : NULL;
+
        if (!pgm &&
            DIFF_FILE_VALID(one) && DIFF_FILE_VALID(two) &&
            (S_IFMT & one->mode) != (S_IFMT & two->mode)) {
@@ -666,6 +744,9 @@ static void run_diff(struct diff_filepair *p)
        else
                run_external_diff(pgm, name, other, one, two, xfrm_msg,
                                  complete_rewrite);
+
+       free(name_munged);
+       free(other_munged);
 }
 
 void diff_setup(struct diff_options *options)
@@ -675,13 +756,19 @@ void diff_setup(struct diff_options *options)
        options->line_termination = '\n';
        options->break_opt = -1;
        options->rename_limit = -1;
+
+       options->change = diff_change;
+       options->add_remove = diff_addremove;
 }
 
 int diff_setup_done(struct diff_options *options)
 {
-       if ((options->find_copies_harder || 0 <= options->rename_limit) &&
-           options->detect_rename != DIFF_DETECT_COPY)
+       if ((options->find_copies_harder &&
+            options->detect_rename != DIFF_DETECT_COPY) ||
+           (0 <= options->rename_limit && !options->detect_rename))
                return -1;
+       if (options->detect_rename && options->rename_limit < 0)
+               options->rename_limit = diff_rename_limit_default;
        if (options->setup & DIFF_SETUP_USE_CACHE) {
                if (!active_cache)
                        /* read-cache does not die even when it fails
@@ -707,6 +794,8 @@ int diff_opt_parse(struct diff_options *options, const char **av, int ac)
                options->line_termination = 0;
        else if (!strncmp(arg, "-l", 2))
                options->rename_limit = strtoul(arg+2, NULL, 10);
+       else if (!strcmp(arg, "--full-index"))
+               options->full_index = 1;
        else if (!strcmp(arg, "--name-only"))
                options->output_format = DIFF_FORMAT_NAME;
        else if (!strcmp(arg, "--name-status"))
@@ -842,16 +931,13 @@ static void diff_flush_raw(struct diff_filepair *p,
 {
        int two_paths;
        char status[10];
+       const char *path_one, *path_two;
 
+       path_one = p->one->path;
+       path_two = p->two->path;
        if (line_termination) {
-               const char *const err =
-                       "path %s cannot be expressed without -z";
-               if (strchr(p->one->path, line_termination) ||
-                   strchr(p->one->path, inter_name_termination))
-                       die(err, p->one->path);
-               if (strchr(p->two->path, line_termination) ||
-                   strchr(p->two->path, inter_name_termination))
-                       die(err, p->two->path);
+               path_one = quote_one(path_one);
+               path_two = quote_one(path_two);
        }
 
        if (p->score)
@@ -879,16 +965,29 @@ static void diff_flush_raw(struct diff_filepair *p,
                       p->one->mode, p->two->mode, sha1_to_hex(p->one->sha1));
                printf("%s ", sha1_to_hex(p->two->sha1));
        }
-       printf("%s%c%s",status, inter_name_termination, p->one->path);
+       printf("%s%c%s", status, inter_name_termination, path_one);
        if (two_paths)
-               printf("%c%s", inter_name_termination, p->two->path);
+               printf("%c%s", inter_name_termination, path_two);
        putchar(line_termination);
+       if (path_one != p->one->path)
+               free((void*)path_one);
+       if (path_two != p->two->path)
+               free((void*)path_two);
 }
 
 static void diff_flush_name(struct diff_filepair *p,
+                           int inter_name_termination,
                            int line_termination)
 {
-       printf("%s%c", p->two->path, line_termination);
+       char *path = p->two->path;
+
+       if (line_termination)
+               path = quote_one(p->two->path);
+       else
+               path = p->two->path;
+       printf("%s%c", path, line_termination);
+       if (p->two->path != path)
+               free(path);
 }
 
 int diff_unmodified_pair(struct diff_filepair *p)
@@ -925,7 +1024,7 @@ int diff_unmodified_pair(struct diff_filepair *p)
        return 0;
 }
 
-static void diff_flush_patch(struct diff_filepair *p)
+static void diff_flush_patch(struct diff_filepair *p, struct diff_options *o)
 {
        if (diff_unmodified_pair(p))
                return;
@@ -934,7 +1033,7 @@ static void diff_flush_patch(struct diff_filepair *p)
            (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
                return; /* no tree diffs in patch format */ 
 
-       run_diff(p);
+       run_diff(p, o);
 }
 
 int diff_queue_is_empty(void)
@@ -1066,7 +1165,7 @@ void diff_flush(struct diff_options *options)
                        die("internal error in diff-resolve-rename-copy");
                switch (diff_output_format) {
                case DIFF_FORMAT_PATCH:
-                       diff_flush_patch(p);
+                       diff_flush_patch(p, options);
                        break;
                case DIFF_FORMAT_RAW:
                case DIFF_FORMAT_NAME_STATUS:
@@ -1075,7 +1174,9 @@ void diff_flush(struct diff_options *options)
                                       diff_output_format);
                        break;
                case DIFF_FORMAT_NAME:
-                       diff_flush_name(p, line_termination);
+                       diff_flush_name(p,
+                                       inter_name_termination,
+                                       line_termination);
                        break;
                }
                diff_free_filepair(q->queue[i]);