diff options
Diffstat (limited to 'builtin-rev-list.c')
-rw-r--r-- | builtin-rev-list.c | 664 |
1 files changed, 664 insertions, 0 deletions
diff --git a/builtin-rev-list.c b/builtin-rev-list.c new file mode 100644 index 0000000000..de80158fd4 --- /dev/null +++ b/builtin-rev-list.c @@ -0,0 +1,664 @@ +#include "cache.h" +#include "refs.h" +#include "tag.h" +#include "commit.h" +#include "tree.h" +#include "blob.h" +#include "tree-walk.h" +#include "diff.h" +#include "revision.h" +#include "list-objects.h" +#include "builtin.h" +#include "log-tree.h" + +/* bits #0-15 in revision.h */ + +#define COUNTED (1u<<16) + +static const char rev_list_usage[] = +"git-rev-list [OPTION] <commit-id>... [ -- paths... ]\n" +" limiting output:\n" +" --max-count=nr\n" +" --max-age=epoch\n" +" --min-age=epoch\n" +" --sparse\n" +" --no-merges\n" +" --remove-empty\n" +" --all\n" +" --stdin\n" +" --quiet\n" +" ordering output:\n" +" --topo-order\n" +" --date-order\n" +" formatting output:\n" +" --parents\n" +" --objects | --objects-edge\n" +" --unpacked\n" +" --header | --pretty\n" +" --abbrev=nr | --no-abbrev\n" +" --abbrev-commit\n" +" --left-right\n" +" special purpose:\n" +" --bisect\n" +" --bisect-vars\n" +" --bisect-all" +; + +static struct rev_info revs; + +static int bisect_list; +static int show_timestamp; +static int hdr_termination; +static const char *header_prefix; + +static void finish_commit(struct commit *commit); +static void show_commit(struct commit *commit) +{ + if (show_timestamp) + printf("%lu ", commit->date); + if (header_prefix) + fputs(header_prefix, stdout); + if (commit->object.flags & BOUNDARY) + putchar('-'); + else if (revs.left_right) { + if (commit->object.flags & SYMMETRIC_LEFT) + putchar('<'); + else + putchar('>'); + } + if (revs.abbrev_commit && revs.abbrev) + fputs(find_unique_abbrev(commit->object.sha1, revs.abbrev), + stdout); + else + fputs(sha1_to_hex(commit->object.sha1), stdout); + if (revs.parents) { + struct commit_list *parents = commit->parents; + while (parents) { + printf(" %s", sha1_to_hex(parents->item->object.sha1)); + parents = parents->next; + } + } + show_decorations(commit); + if (revs.commit_format == CMIT_FMT_ONELINE) + putchar(' '); + else + putchar('\n'); + + if (revs.verbose_header) { + struct strbuf buf; + strbuf_init(&buf, 0); + pretty_print_commit(revs.commit_format, commit, + &buf, revs.abbrev, NULL, NULL, + revs.date_mode, 0); + if (buf.len) + printf("%s%c", buf.buf, hdr_termination); + strbuf_release(&buf); + } + maybe_flush_or_die(stdout, "stdout"); + finish_commit(commit); +} + +static void finish_commit(struct commit *commit) +{ + if (commit->parents) { + free_commit_list(commit->parents); + commit->parents = NULL; + } + free(commit->buffer); + commit->buffer = NULL; +} + +static void finish_object(struct object_array_entry *p) +{ + if (p->item->type == OBJ_BLOB && !has_sha1_file(p->item->sha1)) + die("missing blob object '%s'", sha1_to_hex(p->item->sha1)); +} + +static void show_object(struct object_array_entry *p) +{ + /* An object with name "foo\n0000000..." can be used to + * confuse downstream git-pack-objects very badly. + */ + const char *ep = strchr(p->name, '\n'); + + finish_object(p); + if (ep) { + printf("%s %.*s\n", sha1_to_hex(p->item->sha1), + (int) (ep - p->name), + p->name); + } + else + printf("%s %s\n", sha1_to_hex(p->item->sha1), p->name); +} + +static void show_edge(struct commit *commit) +{ + printf("-%s\n", sha1_to_hex(commit->object.sha1)); +} + +/* + * This is a truly stupid algorithm, but it's only + * used for bisection, and we just don't care enough. + * + * We care just barely enough to avoid recursing for + * non-merge entries. + */ +static int count_distance(struct commit_list *entry) +{ + int nr = 0; + + while (entry) { + struct commit *commit = entry->item; + struct commit_list *p; + + if (commit->object.flags & (UNINTERESTING | COUNTED)) + break; + if (!(commit->object.flags & TREESAME)) + nr++; + commit->object.flags |= COUNTED; + p = commit->parents; + entry = p; + if (p) { + p = p->next; + while (p) { + nr += count_distance(p); + p = p->next; + } + } + } + + return nr; +} + +static void clear_distance(struct commit_list *list) +{ + while (list) { + struct commit *commit = list->item; + commit->object.flags &= ~COUNTED; + list = list->next; + } +} + +#define DEBUG_BISECT 0 + +static inline int weight(struct commit_list *elem) +{ + return *((int*)(elem->item->util)); +} + +static inline void weight_set(struct commit_list *elem, int weight) +{ + *((int*)(elem->item->util)) = weight; +} + +static int count_interesting_parents(struct commit *commit) +{ + struct commit_list *p; + int count; + + for (count = 0, p = commit->parents; p; p = p->next) { + if (p->item->object.flags & UNINTERESTING) + continue; + count++; + } + return count; +} + +static inline int halfway(struct commit_list *p, int nr) +{ + /* + * Don't short-cut something we are not going to return! + */ + if (p->item->object.flags & TREESAME) + 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; + } +} + +#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) +{ + struct commit_list *p; + + fprintf(stderr, "%s (%d/%d)\n", debug, counted, nr); + + 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 & TREESAME) ? ' ' : '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"); + } +} +#endif /* DEBUG_BISECT */ + +static struct commit_list *best_bisection(struct commit_list *list, int nr) +{ + struct commit_list *p, *best; + int best_distance = -1; + + best = list; + for (p = list; p; p = p->next) { + int distance; + unsigned flags = p->item->object.flags; + + if (flags & TREESAME) + continue; + distance = weight(p); + if (nr - distance < distance) + distance = nr - distance; + if (distance > best_distance) { + best = p; + best_distance = distance; + } + } + + return best; +} + +struct commit_dist { + struct commit *commit; + int distance; +}; + +static int compare_commit_dist(const void *a_, const void *b_) +{ + struct commit_dist *a, *b; + + a = (struct commit_dist *)a_; + b = (struct commit_dist *)b_; + if (a->distance != b->distance) + return b->distance - a->distance; /* desc sort */ + return hashcmp(a->commit->object.sha1, b->commit->object.sha1); +} + +static struct commit_list *best_bisection_sorted(struct commit_list *list, int nr) +{ + struct commit_list *p; + struct commit_dist *array = xcalloc(nr, sizeof(*array)); + int cnt, i; + + for (p = list, cnt = 0; p; p = p->next) { + int distance; + unsigned flags = p->item->object.flags; + + if (flags & TREESAME) + continue; + distance = weight(p); + if (nr - distance < distance) + distance = nr - distance; + array[cnt].commit = p->item; + array[cnt].distance = distance; + cnt++; + } + qsort(array, cnt, sizeof(*array), compare_commit_dist); + for (p = list, i = 0; i < cnt; i++) { + struct name_decoration *r = xmalloc(sizeof(*r) + 100); + struct object *obj = &(array[i].commit->object); + + sprintf(r->name, "dist=%d", array[i].distance); + r->next = add_decoration(&name_decoration, obj, r); + p->item = array[i].commit; + p = p->next; + } + if (p) + p->next = NULL; + free(array); + return list; +} + +/* + * 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 find_all) +{ + int n, counted; + struct commit_list *p; + + counted = 0; + + for (n = 0, p = list; p; p = p->next) { + struct commit *commit = p->item; + unsigned flags = commit->object.flags; + + p->item->util = &weights[n++]; + switch (count_interesting_parents(commit)) { + case 0: + if (!(flags & TREESAME)) { + weight_set(p, 1); + counted++; + 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 + * can reach. So we do not have to run the expensive + * count_distance() for single strand of pearls. + * + * However, if you have more than one parents, you cannot + * just add their distance and one for yourself, since + * they usually reach the same ancestor and you would + * end up counting them twice that way. + * + * So we will first count distance of merges the usual + * way, and then fill the blanks using cheaper algorithm. + */ + for (p = list; p; p = p->next) { + if (p->item->object.flags & UNINTERESTING) + continue; + if (weight(p) != -2) + continue; + weight_set(p, count_distance(p)); + clear_distance(list); + + /* Does it happen to be at exactly half-way? */ + if (!find_all && 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 (0 <= weight(p)) + continue; + 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 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 (!(flags & TREESAME)) { + 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? */ + if (!find_all && halfway(p, nr)) + return p; + } + } + + show_list("bisection 2 counted all", counted, nr, list); + + if (!find_all) + return best_bisection(list, nr); + else + return best_bisection_sorted(list, nr); +} + +static struct commit_list *find_bisection(struct commit_list *list, + int *reaches, int *all, + int find_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; + p->next = last; + last = p; + if (!(flags & TREESAME)) + nr++; + on_list++; + } + 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, find_all); + if (best) { + if (!find_all) + best->next = NULL; + *reaches = weight(best); + } + free(weights); + return best; +} + +static void read_revisions_from_stdin(struct rev_info *revs) +{ + char line[1000]; + + while (fgets(line, sizeof(line), stdin) != NULL) { + int len = strlen(line); + if (len && line[len - 1] == '\n') + line[--len] = 0; + if (!len) + break; + if (line[0] == '-') + die("options not supported in --stdin mode"); + if (handle_revision_arg(line, revs, 0, 1)) + die("bad revision '%s'", line); + } +} + +int cmd_rev_list(int argc, const char **argv, const char *prefix) +{ + struct commit_list *list; + int i; + int read_from_stdin = 0; + int bisect_show_vars = 0; + int bisect_find_all = 0; + int quiet = 0; + + git_config(git_default_config); + init_revisions(&revs, prefix); + revs.abbrev = 0; + revs.commit_format = CMIT_FMT_UNSPECIFIED; + argc = setup_revisions(argc, argv, &revs, NULL); + + for (i = 1 ; i < argc; i++) { + const char *arg = argv[i]; + + if (!strcmp(arg, "--header")) { + revs.verbose_header = 1; + continue; + } + if (!strcmp(arg, "--timestamp")) { + show_timestamp = 1; + continue; + } + if (!strcmp(arg, "--bisect")) { + bisect_list = 1; + continue; + } + if (!strcmp(arg, "--bisect-all")) { + bisect_list = 1; + bisect_find_all = 1; + continue; + } + if (!strcmp(arg, "--bisect-vars")) { + bisect_list = 1; + bisect_show_vars = 1; + continue; + } + if (!strcmp(arg, "--stdin")) { + if (read_from_stdin++) + die("--stdin given twice?"); + read_revisions_from_stdin(&revs); + continue; + } + if (!strcmp(arg, "--quiet")) { + quiet = 1; + continue; + } + usage(rev_list_usage); + + } + if (revs.commit_format != CMIT_FMT_UNSPECIFIED) { + /* The command line has a --pretty */ + hdr_termination = '\n'; + if (revs.commit_format == CMIT_FMT_ONELINE) + header_prefix = ""; + else + header_prefix = "commit "; + } + else if (revs.verbose_header) + /* Only --header was specified */ + revs.commit_format = CMIT_FMT_RAW; + + list = revs.commits; + + if ((!list && + (!(revs.tag_objects||revs.tree_objects||revs.blob_objects) && + !revs.pending.nr)) || + revs.diff) + usage(rev_list_usage); + + save_commit_buffer = revs.verbose_header || revs.grep_filter; + track_object_refs = 0; + if (bisect_list) + revs.limited = 1; + + prepare_revision_walk(&revs); + if (revs.tree_objects) + mark_edges_uninteresting(revs.commits, &revs, show_edge); + + if (bisect_list) { + int reaches = reaches, all = all; + + revs.commits = find_bisection(revs.commits, &reaches, &all, + bisect_find_all); + if (bisect_show_vars) { + int cnt; + char hex[41]; + if (!revs.commits) + return 1; + /* + * revs.commits can reach "reaches" commits among + * "all" commits. If it is good, then there are + * (all-reaches) commits left to be bisected. + * On the other hand, if it is bad, then the set + * to bisect is "reaches". + * A bisect set of size N has (N-1) commits further + * to test, as we already know one bad one. + */ + cnt = all - reaches; + if (cnt < reaches) + cnt = reaches; + strcpy(hex, sha1_to_hex(revs.commits->item->object.sha1)); + + if (bisect_find_all) { + traverse_commit_list(&revs, show_commit, show_object); + printf("------\n"); + } + + printf("bisect_rev=%s\n" + "bisect_nr=%d\n" + "bisect_good=%d\n" + "bisect_bad=%d\n" + "bisect_all=%d\n", + hex, + cnt - 1, + all - reaches - 1, + reaches - 1, + all); + return 0; + } + } + + traverse_commit_list(&revs, + quiet ? finish_commit : show_commit, + quiet ? finish_object : show_object); + + return 0; +} |