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-rw-r--r--builtin/revert.c598
1 files changed, 598 insertions, 0 deletions
diff --git a/builtin/revert.c b/builtin/revert.c
new file mode 100644
index 0000000..8b9d829
--- /dev/null
+++ b/builtin/revert.c
@@ -0,0 +1,598 @@
+#include "cache.h"
+#include "builtin.h"
+#include "object.h"
+#include "commit.h"
+#include "tag.h"
+#include "wt-status.h"
+#include "run-command.h"
+#include "exec_cmd.h"
+#include "utf8.h"
+#include "parse-options.h"
+#include "cache-tree.h"
+#include "diff.h"
+#include "revision.h"
+#include "rerere.h"
+#include "merge-recursive.h"
+#include "refs.h"
+
+/*
+ * This implements the builtins revert and cherry-pick.
+ *
+ * Copyright (c) 2007 Johannes E. Schindelin
+ *
+ * Based on git-revert.sh, which is
+ *
+ * Copyright (c) 2005 Linus Torvalds
+ * Copyright (c) 2005 Junio C Hamano
+ */
+
+static const char * const revert_usage[] = {
+ "git revert [options] <commit-ish>",
+ NULL
+};
+
+static const char * const cherry_pick_usage[] = {
+ "git cherry-pick [options] <commit-ish>",
+ NULL
+};
+
+static int edit, no_replay, no_commit, mainline, signoff, allow_ff;
+static enum { REVERT, CHERRY_PICK } action;
+static struct commit *commit;
+static int commit_argc;
+static const char **commit_argv;
+static int allow_rerere_auto;
+
+static const char *me;
+static const char *strategy;
+
+#define GIT_REFLOG_ACTION "GIT_REFLOG_ACTION"
+
+static char *get_encoding(const char *message);
+
+static const char * const *revert_or_cherry_pick_usage(void)
+{
+ return action == REVERT ? revert_usage : cherry_pick_usage;
+}
+
+static void parse_args(int argc, const char **argv)
+{
+ const char * const * usage_str = revert_or_cherry_pick_usage();
+ int noop;
+ struct option options[] = {
+ OPT_BOOLEAN('n', "no-commit", &no_commit, "don't automatically commit"),
+ OPT_BOOLEAN('e', "edit", &edit, "edit the commit message"),
+ OPT_BOOLEAN('r', NULL, &noop, "no-op (backward compatibility)"),
+ OPT_BOOLEAN('s', "signoff", &signoff, "add Signed-off-by:"),
+ OPT_INTEGER('m', "mainline", &mainline, "parent number"),
+ OPT_RERERE_AUTOUPDATE(&allow_rerere_auto),
+ OPT_STRING(0, "strategy", &strategy, "strategy", "merge strategy"),
+ OPT_END(),
+ OPT_END(),
+ OPT_END(),
+ };
+
+ if (action == CHERRY_PICK) {
+ struct option cp_extra[] = {
+ OPT_BOOLEAN('x', NULL, &no_replay, "append commit name"),
+ OPT_BOOLEAN(0, "ff", &allow_ff, "allow fast-forward"),
+ OPT_END(),
+ };
+ if (parse_options_concat(options, ARRAY_SIZE(options), cp_extra))
+ die("program error");
+ }
+
+ commit_argc = parse_options(argc, argv, NULL, options, usage_str,
+ PARSE_OPT_KEEP_ARGV0 |
+ PARSE_OPT_KEEP_UNKNOWN);
+ if (commit_argc < 2)
+ usage_with_options(usage_str, options);
+
+ commit_argv = argv;
+}
+
+struct commit_message {
+ char *parent_label;
+ const char *label;
+ const char *subject;
+ char *reencoded_message;
+ const char *message;
+};
+
+static int get_message(const char *raw_message, struct commit_message *out)
+{
+ const char *encoding;
+ const char *p, *abbrev, *eol;
+ char *q;
+ int abbrev_len, oneline_len;
+
+ if (!raw_message)
+ return -1;
+ encoding = get_encoding(raw_message);
+ if (!encoding)
+ encoding = "UTF-8";
+ if (!git_commit_encoding)
+ git_commit_encoding = "UTF-8";
+
+ out->reencoded_message = NULL;
+ out->message = raw_message;
+ if (strcmp(encoding, git_commit_encoding))
+ out->reencoded_message = reencode_string(raw_message,
+ git_commit_encoding, encoding);
+ if (out->reencoded_message)
+ out->message = out->reencoded_message;
+
+ abbrev = find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV);
+ abbrev_len = strlen(abbrev);
+
+ /* Find beginning and end of commit subject. */
+ p = out->message;
+ while (*p && (*p != '\n' || p[1] != '\n'))
+ p++;
+ if (*p) {
+ p += 2;
+ for (eol = p + 1; *eol && *eol != '\n'; eol++)
+ ; /* do nothing */
+ } else
+ eol = p;
+ oneline_len = eol - p;
+
+ out->parent_label = xmalloc(strlen("parent of ") + abbrev_len +
+ strlen("... ") + oneline_len + 1);
+ q = out->parent_label;
+ q = mempcpy(q, "parent of ", strlen("parent of "));
+ out->label = q;
+ q = mempcpy(q, abbrev, abbrev_len);
+ q = mempcpy(q, "... ", strlen("... "));
+ out->subject = q;
+ q = mempcpy(q, p, oneline_len);
+ *q = '\0';
+ return 0;
+}
+
+static void free_message(struct commit_message *msg)
+{
+ free(msg->parent_label);
+ free(msg->reencoded_message);
+}
+
+static char *get_encoding(const char *message)
+{
+ const char *p = message, *eol;
+
+ if (!p)
+ die ("Could not read commit message of %s",
+ sha1_to_hex(commit->object.sha1));
+ while (*p && *p != '\n') {
+ for (eol = p + 1; *eol && *eol != '\n'; eol++)
+ ; /* do nothing */
+ if (!prefixcmp(p, "encoding ")) {
+ char *result = xmalloc(eol - 8 - p);
+ strlcpy(result, p + 9, eol - 8 - p);
+ return result;
+ }
+ p = eol;
+ if (*p == '\n')
+ p++;
+ }
+ return NULL;
+}
+
+static void add_message_to_msg(struct strbuf *msgbuf, const char *message)
+{
+ const char *p = message;
+ while (*p && (*p != '\n' || p[1] != '\n'))
+ p++;
+
+ if (!*p)
+ strbuf_addstr(msgbuf, sha1_to_hex(commit->object.sha1));
+
+ p += 2;
+ strbuf_addstr(msgbuf, p);
+}
+
+static void set_author_ident_env(const char *message)
+{
+ const char *p = message;
+ if (!p)
+ die ("Could not read commit message of %s",
+ sha1_to_hex(commit->object.sha1));
+ while (*p && *p != '\n') {
+ const char *eol;
+
+ for (eol = p; *eol && *eol != '\n'; eol++)
+ ; /* do nothing */
+ if (!prefixcmp(p, "author ")) {
+ char *line, *pend, *email, *timestamp;
+
+ p += 7;
+ line = xmemdupz(p, eol - p);
+ email = strchr(line, '<');
+ if (!email)
+ die ("Could not extract author email from %s",
+ sha1_to_hex(commit->object.sha1));
+ if (email == line)
+ pend = line;
+ else
+ for (pend = email; pend != line + 1 &&
+ isspace(pend[-1]); pend--);
+ ; /* do nothing */
+ *pend = '\0';
+ email++;
+ timestamp = strchr(email, '>');
+ if (!timestamp)
+ die ("Could not extract author time from %s",
+ sha1_to_hex(commit->object.sha1));
+ *timestamp = '\0';
+ for (timestamp++; *timestamp && isspace(*timestamp);
+ timestamp++)
+ ; /* do nothing */
+ setenv("GIT_AUTHOR_NAME", line, 1);
+ setenv("GIT_AUTHOR_EMAIL", email, 1);
+ setenv("GIT_AUTHOR_DATE", timestamp, 1);
+ free(line);
+ return;
+ }
+ p = eol;
+ if (*p == '\n')
+ p++;
+ }
+ die ("No author information found in %s",
+ sha1_to_hex(commit->object.sha1));
+}
+
+static char *help_msg(void)
+{
+ struct strbuf helpbuf = STRBUF_INIT;
+ char *msg = getenv("GIT_CHERRY_PICK_HELP");
+
+ if (msg)
+ return msg;
+
+ strbuf_addstr(&helpbuf, " After resolving the conflicts,\n"
+ "mark the corrected paths with 'git add <paths>' or 'git rm <paths>'\n"
+ "and commit the result");
+
+ if (action == CHERRY_PICK) {
+ strbuf_addf(&helpbuf, " with: \n"
+ "\n"
+ " git commit -c %s\n",
+ sha1_to_hex(commit->object.sha1));
+ }
+ else
+ strbuf_addch(&helpbuf, '.');
+ return strbuf_detach(&helpbuf, NULL);
+}
+
+static void write_message(struct strbuf *msgbuf, const char *filename)
+{
+ static struct lock_file msg_file;
+
+ int msg_fd = hold_lock_file_for_update(&msg_file, filename,
+ LOCK_DIE_ON_ERROR);
+ if (write_in_full(msg_fd, msgbuf->buf, msgbuf->len) < 0)
+ die_errno("Could not write to %s.", filename);
+ strbuf_release(msgbuf);
+ if (commit_lock_file(&msg_file) < 0)
+ die("Error wrapping up %s", filename);
+}
+
+static struct tree *empty_tree(void)
+{
+ struct tree *tree = xcalloc(1, sizeof(struct tree));
+
+ tree->object.parsed = 1;
+ tree->object.type = OBJ_TREE;
+ pretend_sha1_file(NULL, 0, OBJ_TREE, tree->object.sha1);
+ return tree;
+}
+
+static NORETURN void die_dirty_index(const char *me)
+{
+ if (read_cache_unmerged()) {
+ die_resolve_conflict(me);
+ } else {
+ if (advice_commit_before_merge)
+ die("Your local changes would be overwritten by %s.\n"
+ "Please, commit your changes or stash them to proceed.", me);
+ else
+ die("Your local changes would be overwritten by %s.\n", me);
+ }
+}
+
+static int fast_forward_to(const unsigned char *to, const unsigned char *from)
+{
+ struct ref_lock *ref_lock;
+
+ read_cache();
+ if (checkout_fast_forward(from, to))
+ exit(1); /* the callee should have complained already */
+ ref_lock = lock_any_ref_for_update("HEAD", from, 0);
+ return write_ref_sha1(ref_lock, to, "cherry-pick");
+}
+
+static void do_recursive_merge(struct commit *base, struct commit *next,
+ const char *base_label, const char *next_label,
+ unsigned char *head, struct strbuf *msgbuf,
+ char *defmsg)
+{
+ struct merge_options o;
+ struct tree *result, *next_tree, *base_tree, *head_tree;
+ int clean, index_fd;
+ static struct lock_file index_lock;
+
+ index_fd = hold_locked_index(&index_lock, 1);
+
+ read_cache();
+ init_merge_options(&o);
+ o.ancestor = base ? base_label : "(empty tree)";
+ o.branch1 = "HEAD";
+ o.branch2 = next ? next_label : "(empty tree)";
+
+ head_tree = parse_tree_indirect(head);
+ next_tree = next ? next->tree : empty_tree();
+ base_tree = base ? base->tree : empty_tree();
+
+ clean = merge_trees(&o,
+ head_tree,
+ next_tree, base_tree, &result);
+
+ if (active_cache_changed &&
+ (write_cache(index_fd, active_cache, active_nr) ||
+ commit_locked_index(&index_lock)))
+ die("%s: Unable to write new index file", me);
+ rollback_lock_file(&index_lock);
+
+ if (!clean) {
+ int i;
+ strbuf_addstr(msgbuf, "\nConflicts:\n\n");
+ for (i = 0; i < active_nr;) {
+ struct cache_entry *ce = active_cache[i++];
+ if (ce_stage(ce)) {
+ strbuf_addch(msgbuf, '\t');
+ strbuf_addstr(msgbuf, ce->name);
+ strbuf_addch(msgbuf, '\n');
+ while (i < active_nr && !strcmp(ce->name,
+ active_cache[i]->name))
+ i++;
+ }
+ }
+ write_message(msgbuf, defmsg);
+ fprintf(stderr, "Automatic %s failed.%s\n",
+ me, help_msg());
+ rerere(allow_rerere_auto);
+ exit(1);
+ }
+ write_message(msgbuf, defmsg);
+ fprintf(stderr, "Finished one %s.\n", me);
+}
+
+static int do_pick_commit(void)
+{
+ unsigned char head[20];
+ struct commit *base, *next, *parent;
+ const char *base_label, *next_label;
+ struct commit_message msg = { NULL, NULL, NULL, NULL, NULL };
+ char *defmsg = NULL;
+ struct strbuf msgbuf = STRBUF_INIT;
+
+ if (no_commit) {
+ /*
+ * We do not intend to commit immediately. We just want to
+ * merge the differences in, so let's compute the tree
+ * that represents the "current" state for merge-recursive
+ * to work on.
+ */
+ if (write_cache_as_tree(head, 0, NULL))
+ die ("Your index file is unmerged.");
+ } else {
+ if (get_sha1("HEAD", head))
+ die ("You do not have a valid HEAD");
+ if (index_differs_from("HEAD", 0))
+ die_dirty_index(me);
+ }
+ discard_cache();
+
+ if (!commit->parents) {
+ if (action == REVERT)
+ die ("Cannot revert a root commit");
+ parent = NULL;
+ }
+ else if (commit->parents->next) {
+ /* Reverting or cherry-picking a merge commit */
+ int cnt;
+ struct commit_list *p;
+
+ if (!mainline)
+ die("Commit %s is a merge but no -m option was given.",
+ sha1_to_hex(commit->object.sha1));
+
+ for (cnt = 1, p = commit->parents;
+ cnt != mainline && p;
+ cnt++)
+ p = p->next;
+ if (cnt != mainline || !p)
+ die("Commit %s does not have parent %d",
+ sha1_to_hex(commit->object.sha1), mainline);
+ parent = p->item;
+ } else if (0 < mainline)
+ die("Mainline was specified but commit %s is not a merge.",
+ sha1_to_hex(commit->object.sha1));
+ else
+ parent = commit->parents->item;
+
+ if (allow_ff && !hashcmp(parent->object.sha1, head))
+ return fast_forward_to(commit->object.sha1, head);
+
+ if (parent && parse_commit(parent) < 0)
+ die("%s: cannot parse parent commit %s",
+ me, sha1_to_hex(parent->object.sha1));
+
+ if (get_message(commit->buffer, &msg) != 0)
+ die("Cannot get commit message for %s",
+ sha1_to_hex(commit->object.sha1));
+
+ /*
+ * "commit" is an existing commit. We would want to apply
+ * the difference it introduces since its first parent "prev"
+ * on top of the current HEAD if we are cherry-pick. Or the
+ * reverse of it if we are revert.
+ */
+
+ defmsg = git_pathdup("MERGE_MSG");
+
+ if (action == REVERT) {
+ base = commit;
+ base_label = msg.label;
+ next = parent;
+ next_label = msg.parent_label;
+ strbuf_addstr(&msgbuf, "Revert \"");
+ strbuf_addstr(&msgbuf, msg.subject);
+ strbuf_addstr(&msgbuf, "\"\n\nThis reverts commit ");
+ strbuf_addstr(&msgbuf, sha1_to_hex(commit->object.sha1));
+
+ if (commit->parents->next) {
+ strbuf_addstr(&msgbuf, ", reversing\nchanges made to ");
+ strbuf_addstr(&msgbuf, sha1_to_hex(parent->object.sha1));
+ }
+ strbuf_addstr(&msgbuf, ".\n");
+ } else {
+ base = parent;
+ base_label = msg.parent_label;
+ next = commit;
+ next_label = msg.label;
+ set_author_ident_env(msg.message);
+ add_message_to_msg(&msgbuf, msg.message);
+ if (no_replay) {
+ strbuf_addstr(&msgbuf, "(cherry picked from commit ");
+ strbuf_addstr(&msgbuf, sha1_to_hex(commit->object.sha1));
+ strbuf_addstr(&msgbuf, ")\n");
+ }
+ }
+
+ if (!strategy || !strcmp(strategy, "recursive") || action == REVERT)
+ do_recursive_merge(base, next, base_label, next_label,
+ head, &msgbuf, defmsg);
+ else {
+ int res;
+ struct commit_list *common = NULL;
+ struct commit_list *remotes = NULL;
+ write_message(&msgbuf, defmsg);
+ commit_list_insert(base, &common);
+ commit_list_insert(next, &remotes);
+ res = try_merge_command(strategy, common,
+ sha1_to_hex(head), remotes);
+ free_commit_list(common);
+ free_commit_list(remotes);
+ if (res) {
+ fprintf(stderr, "Automatic %s with strategy %s failed.%s\n",
+ me, strategy, help_msg());
+ rerere(allow_rerere_auto);
+ exit(1);
+ }
+ }
+
+ free_message(&msg);
+
+ /*
+ *
+ * If we are cherry-pick, and if the merge did not result in
+ * hand-editing, we will hit this commit and inherit the original
+ * author date and name.
+ * If we are revert, or if our cherry-pick results in a hand merge,
+ * we had better say that the current user is responsible for that.
+ */
+
+ if (!no_commit) {
+ /* 6 is max possible length of our args array including NULL */
+ const char *args[6];
+ int res;
+ int i = 0;
+
+ args[i++] = "commit";
+ args[i++] = "-n";
+ if (signoff)
+ args[i++] = "-s";
+ if (!edit) {
+ args[i++] = "-F";
+ args[i++] = defmsg;
+ }
+ args[i] = NULL;
+ res = run_command_v_opt(args, RUN_GIT_CMD);
+ free(defmsg);
+
+ return res;
+ }
+
+ free(defmsg);
+
+ return 0;
+}
+
+static void prepare_revs(struct rev_info *revs)
+{
+ int argc;
+
+ init_revisions(revs, NULL);
+ revs->no_walk = 1;
+ if (action != REVERT)
+ revs->reverse = 1;
+
+ argc = setup_revisions(commit_argc, commit_argv, revs, NULL);
+ if (argc > 1)
+ usage(*revert_or_cherry_pick_usage());
+
+ if (prepare_revision_walk(revs))
+ die("revision walk setup failed");
+
+ if (!revs->commits)
+ die("empty commit set passed");
+}
+
+static int revert_or_cherry_pick(int argc, const char **argv)
+{
+ struct rev_info revs;
+
+ git_config(git_default_config, NULL);
+ me = action == REVERT ? "revert" : "cherry-pick";
+ setenv(GIT_REFLOG_ACTION, me, 0);
+ parse_args(argc, argv);
+
+ if (allow_ff) {
+ if (signoff)
+ die("cherry-pick --ff cannot be used with --signoff");
+ if (no_commit)
+ die("cherry-pick --ff cannot be used with --no-commit");
+ if (no_replay)
+ die("cherry-pick --ff cannot be used with -x");
+ if (edit)
+ die("cherry-pick --ff cannot be used with --edit");
+ }
+
+ if (read_cache() < 0)
+ die("git %s: failed to read the index", me);
+
+ prepare_revs(&revs);
+
+ while ((commit = get_revision(&revs))) {
+ int res = do_pick_commit();
+ if (res)
+ return res;
+ }
+
+ return 0;
+}
+
+int cmd_revert(int argc, const char **argv, const char *prefix)
+{
+ if (isatty(0))
+ edit = 1;
+ action = REVERT;
+ return revert_or_cherry_pick(argc, argv);
+}
+
+int cmd_cherry_pick(int argc, const char **argv, const char *prefix)
+{
+ action = CHERRY_PICK;
+ return revert_or_cherry_pick(argc, argv);
+}
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-22 05:46:25 +0000