Make default merge messages denser.
[gitweb.git] / diff.c
diff --git a/diff.c b/diff.c
index f745cdd6e8bcd356c8b6f26accdd26b8b78be056..046d9a39293fa5d33529b59a251f626785ced233 100644 (file)
--- a/diff.c
+++ b/diff.c
@@ -12,6 +12,7 @@ static const char *diff_opts = "-pu";
 static unsigned char null_sha1[20] = { 0, };
 
 static int reverse_diff;
+static int use_size_cache;
 
 static const char *external_diff(void)
 {
@@ -131,17 +132,23 @@ static void builtin_diff(const char *name_a,
                            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])
+       if (!path1[0][0]) {
                printf("new file mode %s\n", temp[1].mode);
-       else if (!path1[1][0])
+               if (xfrm_msg && xfrm_msg[0])
+                       puts(xfrm_msg);
+       }
+       else if (!path1[1][0]) {
                printf("deleted file mode %s\n", temp[0].mode);
+               if (xfrm_msg && xfrm_msg[0])
+                       puts(xfrm_msg);
+       }
        else {
                if (strcmp(temp[0].mode, temp[1].mode)) {
                        printf("old mode %s\n", temp[0].mode);
                        printf("new mode %s\n", temp[1].mode);
                }
                if (xfrm_msg && xfrm_msg[0])
-                       fputs(xfrm_msg, stdout);
+                       puts(xfrm_msg);
 
                if (strncmp(temp[0].mode, temp[1].mode, 3))
                        /* we do not run diff between different kind
@@ -222,12 +229,61 @@ static int work_tree_matches(const char *name, const unsigned char *sha1)
        return 1;
 }
 
+static struct sha1_size_cache {
+       unsigned char sha1[20];
+       unsigned long size;
+} **sha1_size_cache;
+static int sha1_size_cache_nr, sha1_size_cache_alloc;
+
+static struct sha1_size_cache *locate_size_cache(unsigned char *sha1,
+                                                int find_only,
+                                                unsigned long size)
+{
+       int first, last;
+       struct sha1_size_cache *e;
+
+       first = 0;
+       last = sha1_size_cache_nr;
+       while (last > first) {
+               int cmp, next = (last + first) >> 1;
+               e = sha1_size_cache[next];
+               cmp = memcmp(e->sha1, sha1, 20);
+               if (!cmp)
+                       return e;
+               if (cmp < 0) {
+                       last = next;
+                       continue;
+               }
+               first = next+1;
+       }
+       /* not found */
+       if (find_only)
+               return NULL;
+       /* insert to make it at "first" */
+       if (sha1_size_cache_alloc <= sha1_size_cache_nr) {
+               sha1_size_cache_alloc = alloc_nr(sha1_size_cache_alloc);
+               sha1_size_cache = xrealloc(sha1_size_cache,
+                                          sha1_size_cache_alloc *
+                                          sizeof(*sha1_size_cache));
+       }
+       sha1_size_cache_nr++;
+       if (first < sha1_size_cache_nr)
+               memmove(sha1_size_cache + first + 1, sha1_size_cache + first,
+                       (sha1_size_cache_nr - first - 1) *
+                       sizeof(*sha1_size_cache));
+       e = xmalloc(sizeof(struct sha1_size_cache));
+       sha1_size_cache[first] = e;
+       memcpy(e->sha1, sha1, 20);
+       e->size = size;
+       return e;
+}
+
 /*
  * While doing rename detection and pickaxe operation, we may need to
  * grab the data for the blob (or file) for our own in-core comparison.
  * diff_filespec has data and size fields for this purpose.
  */
-int diff_populate_filespec(struct diff_filespec *s)
+int diff_populate_filespec(struct diff_filespec *s, int size_only)
 {
        int err = 0;
        if (!DIFF_FILE_VALID(s))
@@ -235,6 +291,9 @@ int diff_populate_filespec(struct diff_filespec *s)
        if (S_ISDIR(s->mode))
                return -1;
 
+       if (!use_size_cache)
+               size_only = 0;
+
        if (s->data)
                return err;
        if (!s->sha1_valid ||
@@ -254,6 +313,8 @@ int diff_populate_filespec(struct diff_filespec *s)
                s->size = st.st_size;
                if (!s->size)
                        goto empty;
+               if (size_only)
+                       return 0;
                if (S_ISLNK(st.st_mode)) {
                        int ret;
                        s->data = xmalloc(s->size);
@@ -274,8 +335,21 @@ int diff_populate_filespec(struct diff_filespec *s)
        }
        else {
                char type[20];
-               s->data = read_sha1_file(s->sha1, type, &s->size);
-               s->should_free = 1;
+               struct sha1_size_cache *e;
+
+               if (size_only) {
+                       e = locate_size_cache(s->sha1, 1, 0);
+                       if (e) {
+                               s->size = e->size;
+                               return 0;
+                       }
+                       if (!sha1_file_size(s->sha1, &s->size))
+                               locate_size_cache(s->sha1, 0, s->size);
+               }
+               else {
+                       s->data = read_sha1_file(s->sha1, type, &s->size);
+                       s->should_free = 1;
+               }
        }
        return 0;
 }
@@ -355,13 +429,18 @@ static void prepare_temp_file(const char *name,
                                strcpy(temp->hex, sha1_to_hex(null_sha1));
                        else
                                strcpy(temp->hex, sha1_to_hex(one->sha1));
-                       sprintf(temp->mode, "%06o",
-                               S_IFREG |ce_permissions(st.st_mode));
+                       /* Even though we may sometimes borrow the
+                        * contents from the work tree, we always want
+                        * one->mode.  mode is trustworthy even when
+                        * !(one->sha1_valid), as long as
+                        * DIFF_FILE_VALID(one).
+                        */
+                       sprintf(temp->mode, "%06o", one->mode);
                }
                return;
        }
        else {
-               if (diff_populate_filespec(one))
+               if (diff_populate_filespec(one, 0))
                        die("cannot read data blob for %s", one->path);
                prep_temp_blob(temp, one->data, one->size,
                               one->sha1, one->mode);
@@ -492,9 +571,74 @@ static void run_diff(const char *name,
                run_external_diff(pgm, name, other, one, two, xfrm_msg);
 }
 
-void diff_setup(int reverse_diff_)
+void diff_setup(int flags)
+{
+       if (flags & DIFF_SETUP_REVERSE)
+               reverse_diff = 1;
+       if (flags & DIFF_SETUP_USE_CACHE) {
+               if (!active_cache)
+                       /* read-cache does not die even when it fails
+                        * so it is safe for us to do this here.  Also
+                        * it does not smudge active_cache or active_nr
+                        * when it fails, so we do not have to worry about
+                        * cleaning it up oufselves either.
+                        */
+                       read_cache();
+       }
+       if (flags & DIFF_SETUP_USE_SIZE_CACHE)
+               use_size_cache = 1;
+       
+}
+
+static int parse_num(const char **cp_p)
 {
-       reverse_diff = reverse_diff_;
+       int num, scale, ch, cnt;
+       const char *cp = *cp_p;
+
+       cnt = num = 0;
+       scale = 1;
+       while ('0' <= (ch = *cp) && ch <= '9') {
+               if (cnt++ < 5) {
+                       /* We simply ignore more than 5 digits precision. */
+                       scale *= 10;
+                       num = num * 10 + ch - '0';
+               }
+               *cp++;
+       }
+       *cp_p = cp;
+
+       /* user says num divided by scale and we say internally that
+        * is MAX_SCORE * num / scale.
+        */
+       return (MAX_SCORE * num / scale);
+}
+
+int diff_scoreopt_parse(const char *opt)
+{
+       int opt1, opt2, cmd;
+
+       if (*opt++ != '-')
+               return -1;
+       cmd = *opt++;
+       if (cmd != 'M' && cmd != 'C' && cmd != 'B')
+               return -1; /* that is not a -M, -C nor -B option */
+
+       opt1 = parse_num(&opt);
+       if (cmd != 'B')
+               opt2 = 0;
+       else {
+               if (*opt == 0)
+                       opt2 = 0;
+               else if (*opt != '/')
+                       return -1; /* we expect -B80/99 or -B80 */
+               else {
+                       opt++;
+                       opt2 = parse_num(&opt);
+               }
+       }
+       if (*opt != 0)
+               return -1;
+       return opt1 | (opt2 << 16);
 }
 
 struct diff_queue_struct diff_queued_diff;
@@ -517,10 +661,19 @@ struct diff_filepair *diff_queue(struct diff_queue_struct *queue,
        dp->one = one;
        dp->two = two;
        dp->score = 0;
+       dp->source_stays = 0;
+       dp->broken_pair = 0;
        diff_q(queue, dp);
        return dp;
 }
 
+void diff_free_filepair(struct diff_filepair *p)
+{
+       diff_free_filespec_data(p->one);
+       diff_free_filespec_data(p->two);
+       free(p);
+}
+
 static void diff_flush_raw(struct diff_filepair *p,
                           int line_termination,
                           int inter_name_termination)
@@ -544,6 +697,16 @@ static void diff_flush_raw(struct diff_filepair *p,
                sprintf(status, "%c%03d", p->status,
                        (int)(0.5 + p->score * 100.0/MAX_SCORE));
                break;
+       case 'N': case 'D':
+               two_paths = 0;
+               if (p->score)
+                       sprintf(status, "%c%03d", p->status,
+                               (int)(0.5 + p->score * 100.0/MAX_SCORE));
+               else {
+                       status[0] = p->status;
+                       status[1] = 0;
+               }
+               break;
        default:
                two_paths = 0;
                status[0] = p->status;
@@ -615,7 +778,7 @@ static void diff_flush_patch(struct diff_filepair *p)
                sprintf(msg_,
                        "similarity index %d%%\n"
                        "copy from %s\n"
-                       "copy to %s\n",
+                       "copy to %s",
                        (int)(0.5 + p->score * 100.0/MAX_SCORE),
                        p->one->path, p->two->path);
                msg = msg_;
@@ -623,12 +786,22 @@ static void diff_flush_patch(struct diff_filepair *p)
        case 'R':
                sprintf(msg_,
                        "similarity index %d%%\n"
-                       "rename old %s\n"
-                       "rename new %s\n",
+                       "rename from %s\n"
+                       "rename to %s",
                        (int)(0.5 + p->score * 100.0/MAX_SCORE),
                        p->one->path, p->two->path);
                msg = msg_;
                break;
+       case 'D': case 'N':
+               if (DIFF_PAIR_BROKEN(p)) {
+                       sprintf(msg_,
+                               "dissimilarity index %d%%",
+                               (int)(0.5 + p->score * 100.0/MAX_SCORE));
+                       msg = msg_;
+               }
+               else
+                       msg = NULL;
+               break;
        default:
                msg = NULL;
        }
@@ -639,28 +812,6 @@ static void diff_flush_patch(struct diff_filepair *p)
                run_diff(name, other, p->one, p->two, msg);
 }
 
-int diff_needs_to_stay(struct diff_queue_struct *q, int i,
-                      struct diff_filespec *it)
-{
-       /* If it will be used in later entry (either stay or used
-        * as the source of rename/copy), we need to copy, not rename.
-        */
-       while (i < q->nr) {
-               struct diff_filepair *p = q->queue[i++];
-               if (!DIFF_FILE_VALID(p->two))
-                       continue; /* removed is fine */
-               if (strcmp(p->one->path, it->path))
-                       continue; /* not relevant */
-
-               /* p has its src set to *it and it is not a delete;
-                * it will be used for in-place change, rename/copy,
-                * or just stays there.  We cannot rename it out.
-                */
-               return 1;
-       }
-       return 0;
-}
-
 int diff_queue_is_empty(void)
 {
        struct diff_queue_struct *q = &diff_queued_diff;
@@ -689,8 +840,9 @@ 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\n",
-               p->score, p->status ? : '?');
+       fprintf(stderr, "score %d, status %c stays %d broken %d\n",
+               p->score, p->status ? : '?',
+               p->source_stays, p->broken_pair);
 }
 
 void diff_debug_queue(const char *msg, struct diff_queue_struct *q)
@@ -712,8 +864,6 @@ static void diff_resolve_rename_copy(void)
        struct diff_filepair *p, *pp;
        struct diff_queue_struct *q = &diff_queued_diff;
 
-       /* This should not depend on the ordering of things. */
-
        diff_debug_queue("resolve-rename-copy", q);
 
        for (i = 0; i < q->nr; i++) {
@@ -721,24 +871,10 @@ static void diff_resolve_rename_copy(void)
                p->status = 0; /* undecided */
                if (DIFF_PAIR_UNMERGED(p))
                        p->status = 'U';
-               else if (!DIFF_FILE_VALID((p)->one))
+               else if (!DIFF_FILE_VALID(p->one))
                        p->status = 'N';
-               else if (!DIFF_FILE_VALID((p)->two)) {
-                       /* Deletion record should be omitted if there
-                        * are rename/copy entries using this one as
-                        * the source.  Then we can say one of them
-                        * is a rename and the rest are copies.
-                        */
+               else if (!DIFF_FILE_VALID(p->two))
                        p->status = 'D';
-                       for (j = 0; j < q->nr; j++) {
-                               pp = q->queue[j];
-                               if (!strcmp(pp->one->path, p->one->path) &&
-                                   strcmp(pp->one->path, pp->two->path)) {
-                                       p->status = 'X';
-                                       break;
-                               }
-                       }
-               }
                else if (DIFF_PAIR_TYPE_CHANGED(p))
                        p->status = 'T';
 
@@ -746,33 +882,24 @@ static void diff_resolve_rename_copy(void)
                 * whose both sides are valid and of the same type, i.e.
                 * either in-place edit or rename/copy edit.
                 */
-               else if (strcmp(p->one->path, p->two->path)) {
-                       /* See if there is somebody else anywhere that
-                        * will keep the path (either modified or
-                        * unmodified).  If so, we have to be a copy,
-                        * not a rename.  In addition, if there is
-                        * some other rename or copy that comes later
-                        * than us that uses the same source, we
-                        * have to be a copy, not a rename.
+               else if (DIFF_PAIR_RENAME(p)) {
+                       if (p->source_stays) {
+                               p->status = 'C';
+                               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.
                         */
-                       for (j = 0; j < q->nr; j++) {
+                       for (j = i + 1; j < q->nr; j++) {
                                pp = q->queue[j];
                                if (strcmp(pp->one->path, p->one->path))
-                                       continue;
-                               if (!strcmp(pp->one->path, pp->two->path)) {
-                                       if (DIFF_FILE_VALID(pp->two)) {
-                                               /* non-delete */
-                                               p->status = 'C';
-                                               break;
-                                       }
-                                       continue;
-                               }
-                               /* pp is a rename/copy ... */
-                               if (i < j) {
-                                       /* ... and comes later than us */
-                                       p->status = 'C';
-                                       break;
-                               }
+                                       continue; /* not us */
+                               if (!DIFF_PAIR_RENAME(pp))
+                                       continue; /* not a rename/copy */
+                               /* pp is a rename/copy from the same source */
+                               p->status = 'C';
+                               break;
                        }
                        if (!p->status)
                                p->status = 'R';
@@ -780,9 +907,14 @@ static void diff_resolve_rename_copy(void)
                else if (memcmp(p->one->sha1, p->two->sha1, 20) ||
                         p->one->mode != p->two->mode)
                        p->status = 'M';
-               else
-                       /* this is a "no-change" entry */
+               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';
+               }
        }
        diff_debug_queue("resolve-rename-copy done", q);
 }
@@ -817,17 +949,33 @@ void diff_flush(int diff_output_style, int resolve_rename_copy)
                        break;
                }
        }
-       for (i = 0; i < q->nr; i++) {
-               struct diff_filepair *p = q->queue[i];
-               diff_free_filespec_data(p->one);
-               diff_free_filespec_data(p->two);
-               free(p);
-       }
+       for (i = 0; i < q->nr; i++)
+               diff_free_filepair(q->queue[i]);
        free(q->queue);
        q->queue = NULL;
        q->nr = q->alloc = 0;
 }
 
+void diffcore_std(const char **paths,
+                 int detect_rename, int rename_score,
+                 const char *pickaxe, int pickaxe_opts,
+                 int break_opt,
+                 const char *orderfile)
+{
+       if (paths && paths[0])
+               diffcore_pathspec(paths);
+       if (break_opt != -1)
+               diffcore_break(break_opt);
+       if (detect_rename)
+               diffcore_rename(detect_rename, rename_score);
+       if (break_opt != -1)
+               diffcore_merge_broken();
+       if (pickaxe)
+               diffcore_pickaxe(pickaxe, pickaxe_opts);
+       if (orderfile)
+               diffcore_order(orderfile);
+}
+
 void diff_addremove(int addremove, unsigned mode,
                    const unsigned char *sha1,
                    const char *base, const char *path)
@@ -883,7 +1031,7 @@ void diff_helper_input(unsigned old_mode,
        if (new_mode)
                fill_filespec(two, new_sha1, new_mode);
        dp = diff_queue(&diff_queued_diff, one, two);
-       dp->score = score;
+       dp->score = score * MAX_SCORE / 100;
        dp->status = status;
 }