#include "cache.h"
+#include "commit.h"
-#define SEEN 1
-
-struct parent {
- struct revision *parent;
- struct parent *next;
-};
+/*
+ * revision.h leaves the low 16 bits of the "flags" field of the
+ * revision data structure unused. We use it for a "reachable from
+ * this commit <N>" bitmask.
+ */
+#define MAX_COMMITS 16
+#define REACHABLE (1U << 16)
-struct revision {
- unsigned int flags;
- unsigned char sha1[20];
- struct parent *parent;
-};
+#define cmit_flags(cmit) ((cmit)->object.flags & ~REACHABLE)
-static struct revision **revs;
-static int nr_revs, rev_allocs;
+static int show_edges = 0;
+static int basemask = 0;
-static int find_rev(unsigned char *sha1)
+static void read_cache_file(const char *path)
{
- int first = 0, last = nr_revs;
-
- while (first < last) {
- int next = (first + last) / 2;
- struct revision *rev = revs[next];
- int cmp;
-
- cmp = memcmp(sha1, rev->sha1, 20);
- if (!cmp)
- return next;
- if (cmp < 0) {
- last = next;
- continue;
- }
- first = next+1;
- }
- return -first-1;
+ die("no revtree cache file yet");
}
-static struct revision *lookup_rev(unsigned char *sha1)
-{
- int pos = find_rev(sha1);
- struct revision *n;
-
- if (pos >= 0)
- return revs[pos];
-
- pos = -pos-1;
-
- if (rev_allocs == nr_revs) {
- rev_allocs = alloc_nr(rev_allocs);
- revs = realloc(revs, rev_allocs * sizeof(struct revision *));
- }
- n = malloc(sizeof(struct revision));
-
- n->flags = 0;
- memcpy(n->sha1, sha1, 20);
- n->parent = NULL;
-
- /* Insert it into the right place */
- memmove(revs + pos + 1, revs + pos, (nr_revs - pos) * sizeof(struct revision *));
- revs[pos] = n;
- nr_revs++;
-
- return n;
-}
-
-static int add_relationship(struct revision *rev, unsigned char *parent_sha)
+/*
+ * Some revisions are less interesting than others.
+ *
+ * For example, if we use a cache-file, that one may contain
+ * revisions that were never used. They are never interesting.
+ *
+ * And sometimes we're only interested in "edge" commits, ie
+ * places where the marking changes between parent and child.
+ */
+static int interesting(struct commit *rev)
{
- struct revision *parent_rev = lookup_rev(parent_sha);
- struct parent **pp = &rev->parent, *p;
+ unsigned mask = cmit_flags(rev);
- while ((p = *pp) != NULL) {
- if (p->parent == parent_rev)
- return 0;
- pp = &p->next;
- }
-
- p = malloc(sizeof(*p));
- p->parent = parent_rev;
- p->next = NULL;
- *pp = p;
- return 1;
-}
-
-static int parse_commit(unsigned char *sha1)
-{
- struct revision *rev = lookup_rev(sha1);
-
- if (!(rev->flags & SEEN)) {
- void *buffer;
- unsigned long size;
- char type[20];
- unsigned char parent[20];
-
- rev->flags |= SEEN;
- buffer = read_sha1_file(sha1, type, &size);
- if (!buffer || strcmp(type, "commit"))
- return -1;
- buffer += 46; /* "tree " + "hex sha1" + "\n" */
- while (!memcmp(buffer, "parent ", 7) && !get_sha1_hex(buffer+7, parent)) {
- add_relationship(rev, parent);
- parse_commit(parent);
- buffer += 48; /* "parent " + "hex sha1" + "\n" */
+ if (!mask)
+ return 0;
+ if (show_edges) {
+ struct commit_list *p = rev->parents;
+ while (p) {
+ if (mask != cmit_flags(p->item))
+ return 1;
+ p = p->next;
}
+ return 0;
}
- return 0;
-}
+ if (mask & basemask)
+ return 0;
-static void read_cache_file(const char *path)
-{
- FILE *file = fopen(path, "r");
- char line[100];
-
- while (fgets(line, sizeof(line), file)) {
- unsigned char sha1[20], parent[20];
- if (get_sha1_hex(line, sha1) || get_sha1_hex(line + 41, parent))
- usage("bad rev-tree cache file %s", path);
- add_relationship(lookup_rev(sha1), parent);
- }
- fclose(file);
+ return 1;
}
/*
- * Usage: rev-tree [--cache <cache-file>] <commit-id>
+ * Usage: git-rev-tree [--edges] [--cache <cache-file>] <commit-id> [<commit-id2>]
*
* The cache-file can be quite important for big trees. This is an
* expensive operation if you have to walk the whole chain of
int main(int argc, char **argv)
{
int i;
- unsigned char sha1[20];
+ int nr = 0;
+ unsigned char sha1[MAX_COMMITS][20];
+ struct commit_list *list = NULL;
+
+ /*
+ * First - pick up all the revisions we can (both from
+ * caches and from commit file chains).
+ */
+ for (i = 1; i < argc ; i++) {
+ char *arg = argv[i];
+ struct commit *commit;
+
+ if (!strcmp(arg, "--cache")) {
+ read_cache_file(argv[++i]);
+ continue;
+ }
- while (argc > 2) {
- if (!strcmp(argv[1], "--cache")) {
- read_cache_file(argv[2]);
- argv += 2;
- argc -= 2;
+ if (!strcmp(arg, "--edges")) {
+ show_edges = 1;
continue;
}
- usage("unknown option %s", argv[1]);
+
+ if (arg[0] == '^') {
+ arg++;
+ basemask |= 1<<nr;
+ }
+ if (nr >= MAX_COMMITS || get_sha1(arg, sha1[nr]))
+ usage("git-rev-tree [--edges] [--cache <cache-file>] <commit-id> [<commit-id>]");
+
+ commit = lookup_commit_reference(sha1[nr]);
+ if (!commit || parse_commit(commit) < 0)
+ die("bad commit object");
+ commit_list_insert(commit, &list);
+ nr++;
}
- if (argc != 2 || get_sha1_hex(argv[1], sha1))
- usage("rev-tree [--cache <cache-file>] <commit-id>");
- parse_commit(sha1);
- for (i = 0; i < nr_revs; i++) {
- struct revision *rev = revs[i];
- struct parent *p;
+ /*
+ * Parse all the commits in date order.
+ *
+ * We really should stop once we know enough, but that's a
+ * decision that isn't trivial to make.
+ */
+ while (list)
+ pop_most_recent_commit(&list, REACHABLE);
+
+ /*
+ * Now we have the maximal tree. Walk the different sha files back to the root.
+ */
+ for (i = 0; i < nr; i++)
+ mark_reachable(&lookup_commit_reference(sha1[i])->object, 1 << i);
+
+ /*
+ * Now print out the results..
+ */
+ for (i = 0; i < nr_objs; i++) {
+ struct object *obj = objs[i];
+ struct commit *commit;
+ struct commit_list *p;
+
+ if (obj->type != commit_type)
+ continue;
+
+ commit = (struct commit *) obj;
+
+ if (!interesting(commit))
+ continue;
- printf("%s", sha1_to_hex(rev->sha1));
- p = rev->parent;
+ printf("%lu %s:%d", commit->date, sha1_to_hex(obj->sha1),
+ cmit_flags(commit));
+ p = commit->parents;
while (p) {
- printf(" %s", sha1_to_hex(p->parent->sha1));
+ printf(" %s:%d", sha1_to_hex(p->item->object.sha1),
+ cmit_flags(p->item));
p = p->next;
}
printf("\n");