[PATCH] document command to show diff of a commit
[gitweb.git] / diff.c
diff --git a/diff.c b/diff.c
index 3cb41c533313fdd70b3f13858c68032aeb08062a..d8d20c2fcb141124bf4c798eb054e5c1be451f68 100644 (file)
--- a/diff.c
+++ b/diff.c
@@ -19,6 +19,7 @@ static const char *external_diff(void)
 {
        static const char *external_diff_cmd = NULL;
        static int done_preparing = 0;
+       const char *env_diff_opts;
 
        if (done_preparing)
                return external_diff_cmd;
@@ -31,21 +32,23 @@ static const char *external_diff(void)
         *
         * GIT_DIFF_OPTS="-c";
         */
-       if (gitenv("GIT_EXTERNAL_DIFF"))
-               external_diff_cmd = gitenv("GIT_EXTERNAL_DIFF");
+       external_diff_cmd = getenv("GIT_EXTERNAL_DIFF");
 
        /* In case external diff fails... */
-       diff_opts = gitenv("GIT_DIFF_OPTS") ? : diff_opts;
+       env_diff_opts = getenv("GIT_DIFF_OPTS");
+       if (env_diff_opts) diff_opts = env_diff_opts;
 
        done_preparing = 1;
        return external_diff_cmd;
 }
 
+#define TEMPFILE_PATH_LEN              50
+
 static struct diff_tempfile {
        const char *name; /* filename external diff should read from */
        char hex[41];
        char mode[10];
-       char tmp_path[50];
+       char tmp_path[TEMPFILE_PATH_LEN];
 } diff_temp[2];
 
 static int count_lines(const char *filename)
@@ -132,8 +135,8 @@ static void builtin_diff(const char *name_a,
                         int complete_rewrite)
 {
        int i, next_at, cmd_size;
-       const char *diff_cmd = "diff -L%s%s -L%s%s";
-       const char *diff_arg  = "%s %s||:"; /* "||:" is to return 0 */
+       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 *input_name_sq[2];
        const char *path0[2];
        const char *path1[2];
@@ -211,14 +214,10 @@ struct diff_filespec *alloc_filespec(const char *path)
 {
        int namelen = strlen(path);
        struct diff_filespec *spec = xmalloc(sizeof(*spec) + namelen + 1);
+
+       memset(spec, 0, sizeof(*spec));
        spec->path = (char *)(spec + 1);
-       strcpy(spec->path, path);
-       spec->should_free = spec->should_munmap = 0;
-       spec->xfrm_flags = 0;
-       spec->size = 0;
-       spec->data = NULL;
-       spec->mode = 0;
-       memset(spec->sha1, 0, 20);
+       memcpy(spec->path, path, namelen+1);
        return spec;
 }
 
@@ -377,8 +376,10 @@ int diff_populate_filespec(struct diff_filespec *s, int size_only)
                if (fd < 0)
                        goto err_empty;
                s->data = mmap(NULL, s->size, PROT_READ, MAP_PRIVATE, fd, 0);
-               s->should_munmap = 1;
                close(fd);
+               if (s->data == MAP_FAILED)
+                       goto err_empty;
+               s->should_munmap = 1;
        }
        else {
                char type[20];
@@ -419,8 +420,7 @@ static void prep_temp_blob(struct diff_tempfile *temp,
 {
        int fd;
 
-       strcpy(temp->tmp_path, ".diff_XXXXXX");
-       fd = mkstemp(temp->tmp_path);
+       fd = git_mkstemp(temp->tmp_path, TEMPFILE_PATH_LEN, ".diff_XXXXXX");
        if (fd < 0)
                die("unable to create temp-file");
        if (write(fd, blob, size) != size)
@@ -528,10 +528,12 @@ static void run_external_diff(const char *pgm,
        pid_t pid;
        int status;
        static int atexit_asked = 0;
+       const char *othername;
 
+       othername = (other? other : name);
        if (one && two) {
                prepare_temp_file(name, &temp[0], one);
-               prepare_temp_file(other ? : name, &temp[1], two);
+               prepare_temp_file(othername, &temp[1], two);
                if (! atexit_asked &&
                    (temp[0].name == temp[0].tmp_path ||
                     temp[1].name == temp[1].tmp_path)) {
@@ -572,7 +574,7 @@ static void run_external_diff(const char *pgm,
                 * otherwise we use the built-in one.
                 */
                if (one && two)
-                       builtin_diff(name, other ? : name, temp, xfrm_msg,
+                       builtin_diff(name, othername, temp, xfrm_msg,
                                     complete_rewrite);
                else
                        printf("* Unmerged path %s\n", name);
@@ -617,7 +619,7 @@ static void run_diff(struct diff_filepair *p)
        other = (strcmp(name, p->two->path) ? p->two->path : NULL);
        one = p->one; two = p->two;
        switch (p->status) {
-       case 'C':
+       case DIFF_STATUS_COPIED:
                sprintf(msg_,
                        "similarity index %d%%\n"
                        "copy from %s\n"
@@ -626,7 +628,7 @@ static void run_diff(struct diff_filepair *p)
                        name, other);
                xfrm_msg = msg_;
                break;
-       case 'R':
+       case DIFF_STATUS_RENAMED:
                sprintf(msg_,
                        "similarity index %d%%\n"
                        "rename from %s\n"
@@ -635,7 +637,7 @@ static void run_diff(struct diff_filepair *p)
                        name, other);
                xfrm_msg = msg_;
                break;
-       case 'M':
+       case DIFF_STATUS_MODIFIED:
                if (p->score) {
                        sprintf(msg_,
                                "dissimilarity index %d%%",
@@ -699,7 +701,7 @@ static int parse_num(const char **cp_p)
                        scale *= 10;
                        num = num * 10 + ch - '0';
                }
-               *cp++;
+               cp++;
        }
        *cp_p = cp;
 
@@ -760,7 +762,8 @@ struct diff_filepair *diff_queue(struct diff_queue_struct *queue,
        dp->status = 0;
        dp->source_stays = 0;
        dp->broken_pair = 0;
-       diff_q(queue, dp);
+       if (queue)
+               diff_q(queue, dp);
        return dp;
 }
 
@@ -768,6 +771,8 @@ void diff_free_filepair(struct diff_filepair *p)
 {
        diff_free_filespec_data(p->one);
        diff_free_filespec_data(p->two);
+       free(p->one);
+       free(p->two);
        free(p);
 }
 
@@ -779,7 +784,8 @@ static void diff_flush_raw(struct diff_filepair *p,
        char status[10];
 
        if (line_termination) {
-               const char *err = "path %s cannot be expressed without -z";
+               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);
@@ -796,10 +802,12 @@ static void diff_flush_raw(struct diff_filepair *p,
                status[1] = 0;
        }
        switch (p->status) {
-       case 'C': case 'R':
+       case DIFF_STATUS_COPIED:
+       case DIFF_STATUS_RENAMED:
                two_paths = 1;
                break;
-       case 'N': case 'D':
+       case DIFF_STATUS_ADDED:
+       case DIFF_STATUS_DELETED:
                two_paths = 0;
                break;
        default:
@@ -884,13 +892,13 @@ int diff_queue_is_empty(void)
 void diff_debug_filespec(struct diff_filespec *s, int x, const char *one)
 {
        fprintf(stderr, "queue[%d] %s (%s) %s %06o %s\n",
-               x, one ? : "",
+               x, one ? one : "",
                s->path,
                DIFF_FILE_VALID(s) ? "valid" : "invalid",
                s->mode,
                s->sha1_valid ? sha1_to_hex(s->sha1) : "");
        fprintf(stderr, "queue[%d] %s size %lu flags %d\n",
-               x, one ? : "",
+               x, one ? one : "",
                s->size, s->xfrm_flags);
 }
 
@@ -899,7 +907,7 @@ void diff_debug_filepair(const struct diff_filepair *p, int i)
        diff_debug_filespec(p->one, i, "one");
        diff_debug_filespec(p->two, i, "two");
        fprintf(stderr, "score %d, status %c stays %d broken %d\n",
-               p->score, p->status ? : '?',
+               p->score, p->status ? p->status : '?',
                p->source_stays, p->broken_pair);
 }
 
@@ -928,13 +936,13 @@ static void diff_resolve_rename_copy(void)
                p = q->queue[i];
                p->status = 0; /* undecided */
                if (DIFF_PAIR_UNMERGED(p))
-                       p->status = 'U';
+                       p->status = DIFF_STATUS_UNMERGED;
                else if (!DIFF_FILE_VALID(p->one))
-                       p->status = 'N';
+                       p->status = DIFF_STATUS_ADDED;
                else if (!DIFF_FILE_VALID(p->two))
-                       p->status = 'D';
+                       p->status = DIFF_STATUS_DELETED;
                else if (DIFF_PAIR_TYPE_CHANGED(p))
-                       p->status = 'T';
+                       p->status = DIFF_STATUS_TYPE_CHANGED;
 
                /* from this point on, we are dealing with a pair
                 * whose both sides are valid and of the same type, i.e.
@@ -942,12 +950,14 @@ static void diff_resolve_rename_copy(void)
                 */
                else if (DIFF_PAIR_RENAME(p)) {
                        if (p->source_stays) {
-                               p->status = 'C';
+                               p->status = DIFF_STATUS_COPIED;
                                continue;
                        }
                        /* See if there is some other filepair that
                         * copies from the same source as us.  If so
-                        * we are a copy.  Otherwise we are a rename.
+                        * we are a copy.  Otherwise we are either a
+                        * copy if the path stays, or a rename if it
+                        * does not, but we already handled "stays" case.
                         */
                        for (j = i + 1; j < q->nr; j++) {
                                pp = q->queue[j];
@@ -956,22 +966,22 @@ static void diff_resolve_rename_copy(void)
                                if (!DIFF_PAIR_RENAME(pp))
                                        continue; /* not a rename/copy */
                                /* pp is a rename/copy from the same source */
-                               p->status = 'C';
+                               p->status = DIFF_STATUS_COPIED;
                                break;
                        }
                        if (!p->status)
-                               p->status = 'R';
+                               p->status = DIFF_STATUS_RENAMED;
                }
                else if (memcmp(p->one->sha1, p->two->sha1, 20) ||
                         p->one->mode != p->two->mode)
-                       p->status = 'M';
+                       p->status = DIFF_STATUS_MODIFIED;
                else {
                        /* This is a "no-change" entry and should not
                         * happen anymore, but prepare for broken callers.
                         */
                        error("feeding unmodified %s to diffcore",
                              p->one->path);
-                       p->status = 'X';
+                       p->status = DIFF_STATUS_UNKNOWN;
                }
        }
        diff_debug_queue("resolve-rename-copy done", q);
@@ -989,7 +999,7 @@ void diff_flush(int diff_output_style, int line_termination)
        for (i = 0; i < q->nr; i++) {
                struct diff_filepair *p = q->queue[i];
                if ((diff_output_style == DIFF_FORMAT_NO_OUTPUT) ||
-                   (p->status == 'X'))
+                   (p->status == DIFF_STATUS_UNKNOWN))
                        continue;
                if (p->status == 0)
                        die("internal error in diff-resolve-rename-copy");
@@ -1005,9 +1015,8 @@ void diff_flush(int diff_output_style, int line_termination)
                        diff_flush_name(p, line_termination);
                        break;
                }
-       }
-       for (i = 0; i < q->nr; i++)
                diff_free_filepair(q->queue[i]);
+       }
        free(q->queue);
        q->queue = NULL;
        q->nr = q->alloc = 0;
@@ -1024,15 +1033,17 @@ static void diffcore_apply_filter(const char *filter)
        if (!filter)
                return;
 
-       if (strchr(filter, 'A')) {
-               /* All-or-none */
+       if (strchr(filter, DIFF_STATUS_FILTER_AON)) {
                int found;
                for (i = found = 0; !found && i < q->nr; i++) {
                        struct diff_filepair *p = q->queue[i];
-                       if (((p->status == 'M') &&
-                            ((p->score && strchr(filter, 'B')) ||
-                             (!p->score && strchr(filter, 'M')))) ||
-                           ((p->status != 'M') && strchr(filter, p->status)))
+                       if (((p->status == DIFF_STATUS_MODIFIED) &&
+                            ((p->score &&
+                              strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
+                             (!p->score &&
+                              strchr(filter, DIFF_STATUS_MODIFIED)))) ||
+                           ((p->status != DIFF_STATUS_MODIFIED) &&
+                            strchr(filter, p->status)))
                                found++;
                }
                if (found)
@@ -1050,10 +1061,14 @@ static void diffcore_apply_filter(const char *filter)
                /* Only the matching ones */
                for (i = 0; i < q->nr; i++) {
                        struct diff_filepair *p = q->queue[i];
-                       if (((p->status == 'M') &&
-                            ((p->score && strchr(filter, 'B')) ||
-                             (!p->score && strchr(filter, 'M')))) ||
-                           ((p->status != 'M') && strchr(filter, p->status)))
+
+                       if (((p->status == DIFF_STATUS_MODIFIED) &&
+                            ((p->score &&
+                              strchr(filter, DIFF_STATUS_FILTER_BROKEN)) ||
+                             (!p->score &&
+                              strchr(filter, DIFF_STATUS_MODIFIED)))) ||
+                           ((p->status != DIFF_STATUS_MODIFIED) &&
+                            strchr(filter, p->status)))
                                diff_q(&outq, p);
                        else
                                diff_free_filepair(p);