rev-tree.c

   1 #include "cache.h"
   2 #include "commit.h"
   3
   4 /*
   5  * revision.h leaves the low 16 bits of the "flags" field of the
   6  * revision data structure unused. We use it for a "reachable from
   7  * this commit <N>" bitmask.
   8  */
   9 #define MAX_COMMITS 16
  10
  11 static int show_edges = 0;
  12 static int basemask = 0;
  13
  14 static void read_cache_file(const char *path)
  15 {
  16         die("no revtree cache file yet");
  17 }
  18
  19 /*
  20  * Some revisions are less interesting than others.
  21  *
  22  * For example, if we use a cache-file, that one may contain
  23  * revisions that were never used. They are never interesting.
  24  *
  25  * And sometimes we're only interested in "edge" commits, ie
  26  * places where the marking changes between parent and child.
  27  */
  28 static int interesting(struct commit *rev)
  29 {
  30         unsigned mask = rev->object.flags;
  31
  32         if (!mask)
  33                 return 0;
  34         if (show_edges) {
  35                 struct commit_list *p = rev->parents;
  36                 while (p) {
  37                         if (mask != p->item->object.flags)
  38                                 return 1;
  39                         p = p->next;
  40                 }
  41                 return 0;
  42         }
  43         if (mask & basemask)
  44                 return 0;
  45
  46         return 1;
  47 }
  48
  49 void process_commit(unsigned char *sha1)
  50 {
  51         struct commit_list *parents;
  52         struct commit *obj = lookup_commit(sha1);
  53
  54         if (obj && obj->object.parsed)
  55                 return;
  56         if (!obj || parse_commit(obj))
  57                 die("unable to parse commit (%s)", sha1_to_hex(sha1));
  58
  59         parents = obj->parents;
  60         while (parents) {
  61                 process_commit(parents->item->object.sha1);
  62                 parents = parents->next;
  63         }
  64 }
  65
  66 /*
  67  * Usage: rev-tree [--edges] [--cache <cache-file>] <commit-id> [<commit-id2>]
  68  *
  69  * The cache-file can be quite important for big trees. This is an
  70  * expensive operation if you have to walk the whole chain of
  71  * parents in a tree with a long revision history.
  72  */
  73 int main(int argc, char **argv)
  74 {
  75         int i;
  76         int nr = 0;
  77         unsigned char sha1[MAX_COMMITS][20];
  78
  79         /*
  80          * First - pick up all the revisions we can (both from
  81          * caches and from commit file chains).
  82          */
  83         for (i = 1; i < argc ; i++) {
  84                 char *arg = argv[i];
  85
  86                 if (!strcmp(arg, "--cache")) {
  87                         read_cache_file(argv[++i]);
  88                         continue;
  89                 }
  90
  91                 if (!strcmp(arg, "--edges")) {
  92                         show_edges = 1;
  93                         continue;
  94                 }
  95
  96                 if (arg[0] == '^') {
  97                         arg++;
  98                         basemask |= 1<<nr;
  99                 }
 100                 if (nr >= MAX_COMMITS || get_sha1(arg, sha1[nr]))
 101                         usage("rev-tree [--edges] [--cache <cache-file>] <commit-id> [<commit-id>]");
 102                 process_commit(sha1[nr]);
 103                 nr++;
 104         }
 105
 106         /*
 107          * Now we have the maximal tree. Walk the different sha files back to the root.
 108          */
 109         for (i = 0; i < nr; i++)
 110                 mark_reachable(&lookup_commit(sha1[i])->object, 1 << i);
 111
 112         /*
 113          * Now print out the results..
 114          */
 115         for (i = 0; i < nr_objs; i++) {
 116                 struct object *obj = objs[i];
 117                 struct commit *commit;
 118                 struct commit_list *p;
 119
 120                 if (obj->type != commit_type)
 121                         continue;
 122
 123                 commit = (struct commit *) obj;
 124
 125                 if (!interesting(commit))
 126                         continue;
 127
 128                 printf("%lu %s:%d", commit->date, sha1_to_hex(obj->sha1),
 129                        obj->flags);
 130                 p = commit->parents;
 131                 while (p) {
 132                         printf(" %s:%d", sha1_to_hex(p->item->object.sha1),
 133                                p->item->object.flags);
 134                         p = p->next;
 135                 }
 136                 printf("\n");
 137         }
 138         return 0;
 139 }