From: Junio C Hamano Date: Tue, 10 Apr 2007 00:01:27 +0000 (-0700) Subject: Refactor patch-id filtering out of git-cherry and git-format-patch. X-Git-Tag: v1.5.2-rc0~56^2~2 X-Git-Url: http://git.tremily.us/?a=commitdiff_plain;h=5d23e133d23bc9e26d6f23a4d136901e18e6ffba;p=git.git Refactor patch-id filtering out of git-cherry and git-format-patch. This implements the patch-id computation and recording library, patch-ids.c, and rewrites the get_patch_ids() function used in cherry and format-patch to use it, so that they do not pollute the object namespace. Earlier code threw non-objects into the in-core object database, and hoped for not getting bitten by SHA-1 collisions. While it may be practically Ok, it still was an ugly hack. Signed-off-by: Junio C Hamano --- diff --git a/Makefile b/Makefile index a77d31de9..f956c3d9b 100644 --- a/Makefile +++ b/Makefile @@ -283,7 +283,7 @@ LIB_H = \ diff.h object.h pack.h pkt-line.h quote.h refs.h list-objects.h sideband.h \ run-command.h strbuf.h tag.h tree.h git-compat-util.h revision.h \ tree-walk.h log-tree.h dir.h path-list.h unpack-trees.h builtin.h \ - utf8.h reflog-walk.h + utf8.h reflog-walk.h patch-ids.h DIFF_OBJS = \ diff.o diff-lib.o diffcore-break.o diffcore-order.o \ @@ -295,6 +295,7 @@ LIB_OBJS = \ date.o diff-delta.o entry.o exec_cmd.o ident.o \ interpolate.o \ lockfile.o \ + patch-ids.o \ object.o pack-check.o patch-delta.o path.o pkt-line.o sideband.o \ reachable.o reflog-walk.o \ quote.o read-cache.o refs.o run-command.o dir.o object-refs.o \ diff --git a/builtin-log.c b/builtin-log.c index 4a4890aca..eea96901b 100644 --- a/builtin-log.c +++ b/builtin-log.c @@ -12,6 +12,7 @@ #include "builtin.h" #include "tag.h" #include "reflog-walk.h" +#include "patch-ids.h" static int default_show_root = 1; @@ -333,25 +334,12 @@ static int reopen_stdout(struct commit *commit, int nr, int keep_subject) } -static int get_patch_id(struct commit *commit, struct diff_options *options, - unsigned char *sha1) -{ - if (commit->parents) - diff_tree_sha1(commit->parents->item->object.sha1, - commit->object.sha1, "", options); - else - diff_root_tree_sha1(commit->object.sha1, "", options); - diffcore_std(options); - return diff_flush_patch_id(options, sha1); -} - -static void get_patch_ids(struct rev_info *rev, struct diff_options *options, const char *prefix) +static void get_patch_ids(struct rev_info *rev, struct patch_ids *ids, const char *prefix) { struct rev_info check_rev; struct commit *commit; struct object *o1, *o2; unsigned flags1, flags2; - unsigned char sha1[20]; if (rev->pending.nr != 2) die("Need exactly one range."); @@ -364,10 +352,7 @@ static void get_patch_ids(struct rev_info *rev, struct diff_options *options, co if ((flags1 & UNINTERESTING) == (flags2 & UNINTERESTING)) die("Not a range."); - diff_setup(options); - options->recursive = 1; - if (diff_setup_done(options) < 0) - die("diff_setup_done failed"); + init_patch_ids(ids); /* given a range a..b get all patch ids for b..a */ init_revisions(&check_rev, prefix); @@ -382,8 +367,7 @@ static void get_patch_ids(struct rev_info *rev, struct diff_options *options, co if (commit->parents && commit->parents->next) continue; - if (!get_patch_id(commit, options, sha1)) - created_object(sha1, xcalloc(1, sizeof(struct object))); + add_commit_patch_id(commit, ids); } /* reset for next revision walk */ @@ -421,7 +405,7 @@ int cmd_format_patch(int argc, const char **argv, const char *prefix) int ignore_if_in_upstream = 0; int thread = 0; const char *in_reply_to = NULL; - struct diff_options patch_id_opts; + struct patch_ids ids; char *add_signoff = NULL; char message_id[1024]; char ref_message_id[1024]; @@ -560,22 +544,19 @@ int cmd_format_patch(int argc, const char **argv, const char *prefix) } if (ignore_if_in_upstream) - get_patch_ids(&rev, &patch_id_opts, prefix); + get_patch_ids(&rev, &ids, prefix); if (!use_stdout) realstdout = fdopen(dup(1), "w"); prepare_revision_walk(&rev); while ((commit = get_revision(&rev)) != NULL) { - unsigned char sha1[20]; - /* ignore merges */ if (commit->parents && commit->parents->next) continue; if (ignore_if_in_upstream && - !get_patch_id(commit, &patch_id_opts, sha1) && - lookup_object(sha1)) + has_commit_patch_id(commit, &ids)) continue; nr++; @@ -630,6 +611,8 @@ int cmd_format_patch(int argc, const char **argv, const char *prefix) fclose(stdout); } free(list); + if (ignore_if_in_upstream) + free_patch_ids(&ids); return 0; } @@ -652,7 +635,7 @@ static const char cherry_usage[] = int cmd_cherry(int argc, const char **argv, const char *prefix) { struct rev_info revs; - struct diff_options patch_id_opts; + struct patch_ids ids; struct commit *commit; struct commit_list *list = NULL; const char *upstream; @@ -698,7 +681,7 @@ int cmd_cherry(int argc, const char **argv, const char *prefix) return 0; } - get_patch_ids(&revs, &patch_id_opts, prefix); + get_patch_ids(&revs, &ids, prefix); if (limit && add_pending_commit(limit, &revs, UNINTERESTING)) die("Unknown commit %s", limit); @@ -714,12 +697,10 @@ int cmd_cherry(int argc, const char **argv, const char *prefix) } while (list) { - unsigned char sha1[20]; char sign = '+'; commit = list->item; - if (!get_patch_id(commit, &patch_id_opts, sha1) && - lookup_object(sha1)) + if (has_commit_patch_id(commit, &ids)) sign = '-'; if (verbose) { @@ -737,5 +718,6 @@ int cmd_cherry(int argc, const char **argv, const char *prefix) list = list->next; } + free_patch_ids(&ids); return 0; } diff --git a/patch-ids.c b/patch-ids.c new file mode 100644 index 000000000..a288fac99 --- /dev/null +++ b/patch-ids.c @@ -0,0 +1,192 @@ +#include "cache.h" +#include "diff.h" +#include "commit.h" +#include "patch-ids.h" + +static int commit_patch_id(struct commit *commit, struct diff_options *options, + unsigned char *sha1) +{ + if (commit->parents) + diff_tree_sha1(commit->parents->item->object.sha1, + commit->object.sha1, "", options); + else + diff_root_tree_sha1(commit->object.sha1, "", options); + diffcore_std(options); + return diff_flush_patch_id(options, sha1); +} + +static uint32_t take2(const unsigned char *id) +{ + return ((id[0] << 8) | id[1]); +} + +/* + * Conventional binary search loop looks like this: + * + * do { + * int mi = (lo + hi) / 2; + * int cmp = "entry pointed at by mi" minus "target"; + * if (!cmp) + * return (mi is the wanted one) + * if (cmp > 0) + * hi = mi; "mi is larger than target" + * else + * lo = mi+1; "mi is smaller than target" + * } while (lo < hi); + * + * The invariants are: + * + * - When entering the loop, lo points at a slot that is never + * above the target (it could be at the target), hi points at a + * slot that is guaranteed to be above the target (it can never + * be at the target). + * + * - We find a point 'mi' between lo and hi (mi could be the same + * as lo, but never can be the same as hi), and check if it hits + * the target. There are three cases: + * + * - if it is a hit, we are happy. + * + * - if it is strictly higher than the target, we update hi with + * it. + * + * - if it is strictly lower than the target, we update lo to be + * one slot after it, because we allow lo to be at the target. + * + * When choosing 'mi', we do not have to take the "middle" but + * anywhere in between lo and hi, as long as lo <= mi < hi is + * satisfied. When we somehow know that the distance between the + * target and lo is much shorter than the target and hi, we could + * pick mi that is much closer to lo than the midway. + */ +static int patch_pos(struct patch_id **table, int nr, const unsigned char *id) +{ + int hi = nr; + int lo = 0; + int mi = 0; + + if (!nr) + return -1; + + if (nr != 1) { + unsigned lov, hiv, miv, ofs; + + for (ofs = 0; ofs < 18; ofs += 2) { + lov = take2(table[0]->patch_id + ofs); + hiv = take2(table[nr-1]->patch_id + ofs); + miv = take2(id + ofs); + if (miv < lov) + return -1; + if (hiv < miv) + return -1 - nr; + if (lov != hiv) { + /* + * At this point miv could be equal + * to hiv (but id could still be higher); + * the invariant of (mi < hi) should be + * kept. + */ + mi = (nr-1) * (miv - lov) / (hiv - lov); + if (lo <= mi && mi < hi) + break; + die("oops"); + } + } + if (18 <= ofs) + die("cannot happen -- lo and hi are identical"); + } + + do { + int cmp; + cmp = hashcmp(table[mi]->patch_id, id); + if (!cmp) + return mi; + if (cmp > 0) + hi = mi; + else + lo = mi + 1; + mi = (hi + lo) / 2; + } while (lo < hi); + return -lo-1; +} + +#define BUCKET_SIZE 190 /* 190 * 21 = 3990, with slop close enough to 4K */ +struct patch_id_bucket { + struct patch_id_bucket *next; + int nr; + struct patch_id bucket[BUCKET_SIZE]; +}; + +int init_patch_ids(struct patch_ids *ids) +{ + memset(ids, 0, sizeof(*ids)); + diff_setup(&ids->diffopts); + ids->diffopts.recursive = 1; + if (diff_setup_done(&ids->diffopts) < 0) + return error("diff_setup_done failed"); + return 0; +} + +int free_patch_ids(struct patch_ids *ids) +{ + struct patch_id_bucket *next, *patches; + + free(ids->table); + for (patches = ids->patches; patches; patches = next) { + next = patches->next; + free(patches); + } + return 0; +} + +static struct patch_id *add_commit(struct commit *commit, + struct patch_ids *ids, + int no_add) +{ + struct patch_id_bucket *bucket; + struct patch_id *ent; + unsigned char sha1[20]; + int pos; + + if (commit_patch_id(commit, &ids->diffopts, sha1)) + return NULL; + pos = patch_pos(ids->table, ids->nr, sha1); + if (0 <= pos) + return ids->table[pos]; + if (no_add) + return NULL; + + pos = -1 - pos; + + bucket = ids->patches; + if (!bucket || (BUCKET_SIZE <= bucket->nr)) { + bucket = xcalloc(1, sizeof(*bucket)); + bucket->next = ids->patches; + ids->patches = bucket; + } + ent = &bucket->bucket[bucket->nr++]; + hashcpy(ent->patch_id, sha1); + + if (ids->alloc <= ids->nr) { + ids->alloc = alloc_nr(ids->nr); + ids->table = xrealloc(ids->table, sizeof(ent) * ids->alloc); + } + if (pos < ids->nr) + memmove(ids->table + pos + 1, ids->table + pos, + sizeof(ent) * (ids->nr - pos)); + ids->nr++; + ids->table[pos] = ent; + return ids->table[pos]; +} + +struct patch_id *has_commit_patch_id(struct commit *commit, + struct patch_ids *ids) +{ + return add_commit(commit, ids, 1); +} + +struct patch_id *add_commit_patch_id(struct commit *commit, + struct patch_ids *ids) +{ + return add_commit(commit, ids, 0); +} diff --git a/patch-ids.h b/patch-ids.h new file mode 100644 index 000000000..c8c7ca110 --- /dev/null +++ b/patch-ids.h @@ -0,0 +1,21 @@ +#ifndef PATCH_IDS_H +#define PATCH_IDS_H + +struct patch_id { + unsigned char patch_id[20]; + char seen; +}; + +struct patch_ids { + struct diff_options diffopts; + int nr, alloc; + struct patch_id **table; + struct patch_id_bucket *patches; +}; + +int init_patch_ids(struct patch_ids *); +int free_patch_ids(struct patch_ids *); +struct patch_id *add_commit_patch_id(struct commit *, struct patch_ids *); +struct patch_id *has_commit_patch_id(struct commit *, struct patch_ids *); + +#endif /* PATCH_IDS_H */