summaryrefslogtreecommitdiff
path: root/builtin-rev-list.c
diff options
context:
space:
mode:
Diffstat (limited to 'builtin-rev-list.c')
-rw-r--r--builtin-rev-list.c562
1 files changed, 562 insertions, 0 deletions
diff --git a/builtin-rev-list.c b/builtin-rev-list.c
new file mode 100644
index 0000000000..8efd609b12
--- /dev/null
+++ b/builtin-rev-list.c
@@ -0,0 +1,562 @@
+#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"
+
+/* 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"
+" 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"
+;
+
+static struct rev_info revs;
+
+static int bisect_list;
+static int show_timestamp;
+static int hdr_termination;
+static const char *header_prefix;
+
+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;
+ }
+ }
+ if (revs.commit_format == CMIT_FMT_ONELINE)
+ putchar(' ');
+ else
+ putchar('\n');
+
+ if (revs.verbose_header) {
+ char *buf = NULL;
+ unsigned long buflen = 0;
+ pretty_print_commit(revs.commit_format, commit, ~0,
+ &buf, &buflen,
+ revs.abbrev, NULL, NULL, revs.date_mode);
+ printf("%s%c", buf, hdr_termination);
+ free(buf);
+ }
+ maybe_flush_or_die(stdout, "stdout");
+ if (commit->parents) {
+ free_commit_list(commit->parents);
+ commit->parents = NULL;
+ }
+ free(commit->buffer);
+ commit->buffer = NULL;
+}
+
+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');
+
+ 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),
+ 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 (!revs.prune_fn || (commit->object.flags & TREECHANGE))
+ 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 distance, int nr)
+{
+ /*
+ * 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.
+ */
+ distance *= 2;
+ switch (distance - 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 & 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");
+ }
+}
+#endif /* DEBUG_BISECT */
+
+/*
+ * 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 *find_bisection(struct commit_list *list,
+ int *reaches, int *all)
+{
+ int n, nr, on_list, counted, distance;
+ 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 (!revs.prune_fn || (flags & TREECHANGE))
+ nr++;
+ on_list++;
+ }
+ list = last;
+ show_list("bisection 2 sorted", 0, nr, list);
+
+ *all = nr;
+ weights = xcalloc(on_list, sizeof(int*));
+ 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 (!revs.prune_fn || (flags & TREECHANGE)) {
+ 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;
+ n = weight(p);
+ if (n != -2)
+ continue;
+ distance = count_distance(p);
+ clear_distance(list);
+ weight_set(p, distance);
+
+ /* Does it happen to be at exactly half-way? */
+ if (halfway(p, distance, nr)) {
+ p->next = NULL;
+ *reaches = distance;
+ free(weights);
+ 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 (!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);
+ if (halfway(p, distance, nr)) {
+ p->next = NULL;
+ *reaches = distance;
+ free(weights);
+ return p;
+ }
+ }
+ }
+
+ show_list("bisection 2 counted all", counted, nr, list);
+
+ /* Then find the best one */
+ counted = -1;
+ best = list;
+ for (p = list; p; p = p->next) {
+ 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 > counted) {
+ best = p;
+ counted = distance;
+ *reaches = weight(p);
+ }
+ }
+ if (best)
+ best->next = NULL;
+ 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 (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;
+
+ 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-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;
+ }
+ 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);
+ if (bisect_show_vars) {
+ int cnt;
+ 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;
+ printf("bisect_rev=%s\n"
+ "bisect_nr=%d\n"
+ "bisect_good=%d\n"
+ "bisect_bad=%d\n"
+ "bisect_all=%d\n",
+ sha1_to_hex(revs.commits->item->object.sha1),
+ cnt - 1,
+ all - reaches - 1,
+ reaches - 1,
+ all);
+ return 0;
+ }
+ }
+
+ traverse_commit_list(&revs, show_commit, show_object);
+
+ return 0;
+}
generated by cgit v1.2.3 (git 2.25.1) at 2024-12-18 20:33:44 +0000