Add some fancy colors in the test library when terminal supports it.
[gitweb.git] / builtin-rev-list.c
index b395ffeb03340af98f7f2c6447c850f7529d1cfb..33726b8d8426b4878ed63184dc280957ba4434e0 100644 (file)
@@ -35,6 +35,7 @@ static const char rev_list_usage[] =
 "    --header | --pretty\n"
 "    --abbrev=nr | --no-abbrev\n"
 "    --abbrev-commit\n"
+"    --left-right\n"
 "  special purpose:\n"
 "    --bisect\n"
 "    --bisect-vars"
@@ -69,21 +70,9 @@ static void show_commit(struct commit *commit)
        if (revs.parents) {
                struct commit_list *parents = commit->parents;
                while (parents) {
-                       struct object *o = &(parents->item->object);
+                       printf(" %s", sha1_to_hex(parents->item->object.sha1));
                        parents = parents->next;
-                       if (o->flags & TMP_MARK)
-                               continue;
-                       printf(" %s", sha1_to_hex(o->sha1));
-                       o->flags |= TMP_MARK;
                }
-               /* TMP_MARK is a general purpose flag that can
-                * be used locally, but the user should clean
-                * things up after it is done with them.
-                */
-               for (parents = commit->parents;
-                    parents;
-                    parents = parents->next)
-                       parents->item->object.flags &= ~TMP_MARK;
        }
        if (revs.commit_format == CMIT_FMT_ONELINE)
                putchar(' ');
@@ -91,13 +80,15 @@ static void show_commit(struct commit *commit)
                putchar('\n');
 
        if (revs.verbose_header) {
-               static char pretty_header[16384];
-               pretty_print_commit(revs.commit_format, commit, ~0,
-                                   pretty_header, sizeof(pretty_header),
-                                   revs.abbrev, NULL, NULL, revs.relative_date);
-               printf("%s%c", pretty_header, hdr_termination);
+               struct strbuf buf;
+               strbuf_init(&buf, 0);
+               pretty_print_commit(revs.commit_format, commit,
+                                       &buf, revs.abbrev, NULL, NULL, revs.date_mode);
+               if (buf.len)
+                       printf("%s%c", buf.buf, hdr_termination);
+               strbuf_release(&buf);
        }
-       fflush(stdout);
+       maybe_flush_or_die(stdout, "stdout");
        if (commit->parents) {
                free_commit_list(commit->parents);
                commit->parents = NULL;
@@ -112,6 +103,10 @@ static void show_object(struct object_array_entry *p)
         * confuse downstream git-pack-objects very badly.
         */
        const char *ep = strchr(p->name, '\n');
+
+       if (p->item->type == OBJ_BLOB && !has_sha1_file(p->item->sha1))
+               die("missing blob object '%s'", sha1_to_hex(p->item->sha1));
+
        if (ep) {
                printf("%s %.*s\n", sha1_to_hex(p->item->sha1),
                       (int) (ep - p->name),
@@ -169,117 +164,170 @@ static void clear_distance(struct commit_list *list)
        }
 }
 
-static struct commit_list *find_bisection(struct commit_list *list,
-                                         int *reaches, int *all)
+#define DEBUG_BISECT 0
+
+static inline int weight(struct commit_list *elem)
 {
-       int nr, closest;
-       struct commit_list *p, *best;
+       return *((int*)(elem->item->util));
+}
 
-       nr = 0;
-       p = list;
-       while (p) {
-               if (!revs.prune_fn || (p->item->object.flags & TREECHANGE))
-                       nr++;
-               p = p->next;
-       }
-       *all = nr;
-       closest = 0;
-       best = list;
+static inline void weight_set(struct commit_list *elem, int weight)
+{
+       *((int*)(elem->item->util)) = weight;
+}
 
-       for (p = list; p; p = p->next) {
-               int distance, reach;
+static int count_interesting_parents(struct commit *commit)
+{
+       struct commit_list *p;
+       int count;
 
-               if (revs.prune_fn && !(p->item->object.flags & TREECHANGE))
+       for (count = 0, p = commit->parents; p; p = p->next) {
+               if (p->item->object.flags & UNINTERESTING)
                        continue;
-
-               distance = reach = count_distance(p);
-               clear_distance(list);
-               if (nr - distance < distance)
-                       distance = nr - distance;
-               if (distance > closest) {
-                       best = p;
-                       *reaches = reach;
-                       closest = distance;
-               }
+               count++;
        }
-       if (best)
-               best->next = NULL;
-       return best;
+       return count;
 }
 
-static inline int commit_interesting(struct commit_list *elem)
+static inline int halfway(struct commit_list *p, int nr)
 {
-       unsigned flags = elem->item->object.flags;
-       if (flags & UNINTERESTING)
+       /*
+        * Don't short-cut something we are not going to return!
+        */
+       if (revs.prune_fn && !(p->item->object.flags & TREECHANGE))
+               return 0;
+       if (DEBUG_BISECT)
+               return 0;
+       /*
+        * 2 and 3 are halfway of 5.
+        * 3 is halfway of 6 but 2 and 4 are not.
+        */
+       switch (2 * weight(p) - nr) {
+       case -1: case 0: case 1:
+               return 1;
+       default:
                return 0;
-       return (!revs.prune_fn || (flags & TREECHANGE));
+       }
 }
 
-static inline int weight(struct commit_list *elem)
+#if !DEBUG_BISECT
+#define show_list(a,b,c,d) do { ; } while (0)
+#else
+static void show_list(const char *debug, int counted, int nr,
+                     struct commit_list *list)
 {
-       return *((int*)(elem->item->util));
-}
+       struct commit_list *p;
 
-static inline void weight_set(struct commit_list *elem, int weight)
-{
-       *((int*)(elem->item->util)) = weight;
-}
+       fprintf(stderr, "%s (%d/%d)\n", debug, counted, nr);
 
-static int count_interesting_parents(struct commit_list *elem)
-{
-       int cnt = 0;
-       if (!elem->item->parents)
-               return cnt;
-       for (elem = elem->item->parents; elem; elem = elem->next) {
-               if (commit_interesting(elem))
-                       cnt++;
+       for (p = list; p; p = p->next) {
+               struct commit_list *pp;
+               struct commit *commit = p->item;
+               unsigned flags = commit->object.flags;
+               enum object_type type;
+               unsigned long size;
+               char *buf = read_sha1_file(commit->object.sha1, &type, &size);
+               char *ep, *sp;
+
+               fprintf(stderr, "%c%c%c ",
+                       (flags & TREECHANGE) ? 'T' : ' ',
+                       (flags & UNINTERESTING) ? 'U' : ' ',
+                       (flags & COUNTED) ? 'C' : ' ');
+               if (commit->util)
+                       fprintf(stderr, "%3d", weight(p));
+               else
+                       fprintf(stderr, "---");
+               fprintf(stderr, " %.*s", 8, sha1_to_hex(commit->object.sha1));
+               for (pp = commit->parents; pp; pp = pp->next)
+                       fprintf(stderr, " %.*s", 8,
+                               sha1_to_hex(pp->item->object.sha1));
+
+               sp = strstr(buf, "\n\n");
+               if (sp) {
+                       sp += 2;
+                       for (ep = sp; *ep && *ep != '\n'; ep++)
+                               ;
+                       fprintf(stderr, " %.*s", (int)(ep - sp), sp);
+               }
+               fprintf(stderr, "\n");
        }
-       return cnt;
 }
+#endif /* DEBUG_BISECT */
 
-static struct commit_list *find_bisection_2(struct commit_list *list,
-                                           int *reaches, int *all)
+static struct commit_list *best_bisection(struct commit_list *list, int nr)
 {
-       int n, nr, counted, distance;
        struct commit_list *p, *best;
-       int *weights;
+       int best_distance = -1;
 
-       for (nr = 0, p = list; p; p = p->next) {
-               if (commit_interesting(p))
-                       nr++;
+       best = list;
+       for (p = list; p; p = p->next) {
+               int distance;
+               unsigned flags = p->item->object.flags;
+
+               if (revs.prune_fn && !(flags & TREECHANGE))
+                       continue;
+               distance = weight(p);
+               if (nr - distance < distance)
+                       distance = nr - distance;
+               if (distance > best_distance) {
+                       best = p;
+                       best_distance = distance;
+               }
        }
-       *all = nr;
-       weights = xcalloc(nr, sizeof(int*));
+
+       return best;
+}
+
+/*
+ * zero or positive weight is the number of interesting commits it can
+ * reach, including itself.  Especially, weight = 0 means it does not
+ * reach any tree-changing commits (e.g. just above uninteresting one
+ * but traversal is with pathspec).
+ *
+ * weight = -1 means it has one parent and its distance is yet to
+ * be computed.
+ *
+ * weight = -2 means it has more than one parent and its distance is
+ * unknown.  After running count_distance() first, they will get zero
+ * or positive distance.
+ */
+static struct commit_list *do_find_bisection(struct commit_list *list,
+                                            int nr, int *weights)
+{
+       int n, counted;
+       struct commit_list *p;
+
        counted = 0;
 
        for (n = 0, p = list; p; p = p->next) {
-               if (!commit_interesting(p))
-                       continue;
-               if (commit_interesting(p)) {
-                       /*
-                        * positive weight is the number of interesting
-                        * commits it can reach, including itself.
-                        * weight = 0 means it has one parent and
-                        * its distance is unknown.
-                        * weight < 0 means it has more than one
-                        * parent and its distance is unknown.
-                        */
-                       p->item->util = &weights[n++];
-                       switch (count_interesting_parents(p)) {
-                       case 0:
+               struct commit *commit = p->item;
+               unsigned flags = commit->object.flags;
+
+               p->item->util = &weights[n++];
+               switch (count_interesting_parents(commit)) {
+               case 0:
+                       if (!revs.prune_fn || (flags & TREECHANGE)) {
                                weight_set(p, 1);
                                counted++;
-                               break;
-                       case 1:
-                               weight_set(p, 0);
-                               break;
-                       default:
-                               weight_set(p, -1);
-                               break;
+                               show_list("bisection 2 count one",
+                                         counted, nr, list);
                        }
+                       /*
+                        * otherwise, it is known not to reach any
+                        * tree-changing commit and gets weight 0.
+                        */
+                       break;
+               case 1:
+                       weight_set(p, -1);
+                       break;
+               default:
+                       weight_set(p, -2);
+                       break;
                }
        }
 
+       show_list("bisection 2 initialize", counted, nr, list);
+
        /*
         * If you have only one parent in the resulting set
         * then you can reach one commit more than that parent
@@ -295,69 +343,105 @@ static struct commit_list *find_bisection_2(struct commit_list *list,
         * way, and then fill the blanks using cheaper algorithm.
         */
        for (p = list; p; p = p->next) {
-               if (!commit_interesting(p))
+               if (p->item->object.flags & UNINTERESTING)
                        continue;
-               n = weight(p);
-               if (0 <= n)
+               if (weight(p) != -2)
                        continue;
-               distance = count_distance(p);
-               clear_distance(p);
-               weight_set(p, distance);
+               weight_set(p, count_distance(p));
+               clear_distance(list);
 
                /* Does it happen to be at exactly half-way? */
-               distance *= 2;
-               if (nr == distance || (nr+1) == distance) {
-                       p->next = NULL;
-                       *reaches = weight(p);
-                       free(weights);
+               if (halfway(p, nr))
                        return p;
-               }
                counted++;
        }
 
+       show_list("bisection 2 count_distance", counted, nr, list);
+
        while (counted < nr) {
                for (p = list; p; p = p->next) {
                        struct commit_list *q;
+                       unsigned flags = p->item->object.flags;
 
-                       if (!commit_interesting(p) || 0 < weight(p))
+                       if (0 <= weight(p))
                                continue;
-                       for (q = p->item->parents; q; q = q->next)
-                               if (commit_interesting(q) && 0 < weight(q))
+                       for (q = p->item->parents; q; q = q->next) {
+                               if (q->item->object.flags & UNINTERESTING)
+                                       continue;
+                               if (0 <= weight(q))
                                        break;
+                       }
                        if (!q)
                                continue;
-                       weight_set(p, weight(q)+1);
-                       counted++;
+
+                       /*
+                        * weight for p is unknown but q is known.
+                        * add one for p itself if p is to be counted,
+                        * otherwise inherit it from q directly.
+                        */
+                       if (!revs.prune_fn || (flags & TREECHANGE)) {
+                               weight_set(p, weight(q)+1);
+                               counted++;
+                               show_list("bisection 2 count one",
+                                         counted, nr, list);
+                       }
+                       else
+                               weight_set(p, weight(q));
 
                        /* Does it happen to be at exactly half-way? */
-                       distance = weight(p) * 2;
-                       if (nr == distance || (nr+1) == distance) {
-                               p->next = NULL;
-                               *reaches = weight(p);
-                               free(weights);
+                       if (halfway(p, nr))
                                return p;
-                       }
                }
        }
 
+       show_list("bisection 2 counted all", counted, nr, list);
+
        /* Then find the best one */
-       counted = 0;
-       best = list;
-       for (p = list; p; p = p->next) {
-               if (!commit_interesting(p))
+       return best_bisection(list, nr);
+}
+
+static struct commit_list *find_bisection(struct commit_list *list,
+                                         int *reaches, int *all)
+{
+       int nr, on_list;
+       struct commit_list *p, *best, *next, *last;
+       int *weights;
+
+       show_list("bisection 2 entry", 0, 0, list);
+
+       /*
+        * Count the number of total and tree-changing items on the
+        * list, while reversing the list.
+        */
+       for (nr = on_list = 0, last = NULL, p = list;
+            p;
+            p = next) {
+               unsigned flags = p->item->object.flags;
+
+               next = p->next;
+               if (flags & UNINTERESTING)
                        continue;
-               distance = weight(p);
-               if (nr - distance < distance)
-                       distance = nr - distance;
-               if (distance > counted) {
-                       best = p;
-                       counted = distance;
-                       *reaches = weight(p);
-               }
+               p->next = last;
+               last = p;
+               if (!revs.prune_fn || (flags & TREECHANGE))
+                       nr++;
+               on_list++;
        }
-       if (best)
+       list = last;
+       show_list("bisection 2 sorted", 0, nr, list);
+
+       *all = nr;
+       weights = xcalloc(on_list, sizeof(*weights));
+
+       /* Do the real work of finding bisection commit. */
+       best = do_find_bisection(list, nr, weights);
+
+       if (best) {
                best->next = NULL;
+               *reaches = weight(best);
+       }
        free(weights);
+
        return best;
 }
 
@@ -452,12 +536,7 @@ int cmd_rev_list(int argc, const char **argv, const char *prefix)
        if (bisect_list) {
                int reaches = reaches, all = all;
 
-               if (!revs.prune_fn)
-                       revs.commits = find_bisection_2(revs.commits,
-                                                       &reaches, &all);
-               else
-                       revs.commits = find_bisection(revs.commits,
-                                                     &reaches, &all);
+               revs.commits = find_bisection(revs.commits, &reaches, &all);
                if (bisect_show_vars) {
                        int cnt;
                        if (!revs.commits)