diff options
Diffstat (limited to 'builtin-reset.c')
| -rw-r--r-- | builtin-reset.c | 279 |
1 files changed, 279 insertions, 0 deletions
diff --git a/builtin-reset.c b/builtin-reset.c new file mode 100644 index 0000000000..99d5c082a6 --- /dev/null +++ b/builtin-reset.c @@ -0,0 +1,279 @@ +/* + * "git reset" builtin command + * + * Copyright (c) 2007 Carlos Rica + * + * Based on git-reset.sh, which is + * + * Copyright (c) 2005, 2006 Linus Torvalds and Junio C Hamano + */ +#include "cache.h" +#include "tag.h" +#include "object.h" +#include "commit.h" +#include "run-command.h" +#include "refs.h" +#include "diff.h" +#include "diffcore.h" +#include "tree.h" + +static const char builtin_reset_usage[] = +"git-reset [--mixed | --soft | --hard] [<commit-ish>] [ [--] <paths>...]"; + +static char *args_to_str(const char **argv) +{ + char *buf = NULL; + unsigned long len, space = 0, nr = 0; + + for (; *argv; argv++) { + len = strlen(*argv); + ALLOC_GROW(buf, nr + 1 + len, space); + if (nr) + buf[nr++] = ' '; + memcpy(buf + nr, *argv, len); + nr += len; + } + ALLOC_GROW(buf, nr + 1, space); + buf[nr] = '\0'; + + return buf; +} + +static inline int is_merge(void) +{ + return !access(git_path("MERGE_HEAD"), F_OK); +} + +static int unmerged_files(void) +{ + char b; + ssize_t len; + struct child_process cmd; + const char *argv_ls_files[] = {"ls-files", "--unmerged", NULL}; + + memset(&cmd, 0, sizeof(cmd)); + cmd.argv = argv_ls_files; + cmd.git_cmd = 1; + cmd.out = -1; + + if (start_command(&cmd)) + die("Could not run sub-command: git ls-files"); + + len = xread(cmd.out, &b, 1); + if (len < 0) + die("Could not read output from git ls-files: %s", + strerror(errno)); + finish_command(&cmd); + + return len; +} + +static int reset_index_file(const unsigned char *sha1, int is_hard_reset) +{ + int i = 0; + const char *args[6]; + + args[i++] = "read-tree"; + args[i++] = "-v"; + args[i++] = "--reset"; + if (is_hard_reset) + args[i++] = "-u"; + args[i++] = sha1_to_hex(sha1); + args[i] = NULL; + + return run_command_v_opt(args, RUN_GIT_CMD); +} + +static void print_new_head_line(struct commit *commit) +{ + const char *hex, *dots = "...", *body; + + hex = find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV); + if (!hex) { + hex = sha1_to_hex(commit->object.sha1); + dots = ""; + } + printf("HEAD is now at %s%s", hex, dots); + body = strstr(commit->buffer, "\n\n"); + if (body) { + const char *eol; + size_t len; + body += 2; + eol = strchr(body, '\n'); + len = eol ? eol - body : strlen(body); + printf(" %.*s\n", (int) len, body); + } + else + printf("\n"); +} + +static int update_index_refresh(void) +{ + const char *argv_update_index[] = {"update-index", "--refresh", NULL}; + return run_command_v_opt(argv_update_index, RUN_GIT_CMD); +} + +static void update_index_from_diff(struct diff_queue_struct *q, + struct diff_options *opt, void *data) +{ + int i; + + /* do_diff_cache() mangled the index */ + discard_cache(); + read_cache(); + + for (i = 0; i < q->nr; i++) { + struct diff_filespec *one = q->queue[i]->one; + if (one->mode) { + struct cache_entry *ce; + ce = make_cache_entry(one->mode, one->sha1, one->path, + 0, 0); + add_cache_entry(ce, ADD_CACHE_OK_TO_ADD | + ADD_CACHE_OK_TO_REPLACE); + } else + remove_file_from_cache(one->path); + } +} + +static int read_from_tree(const char *prefix, const char **argv, + unsigned char *tree_sha1) +{ + struct lock_file *lock = xcalloc(1, sizeof(struct lock_file)); + int index_fd; + struct diff_options opt; + + memset(&opt, 0, sizeof(opt)); + diff_tree_setup_paths(get_pathspec(prefix, (const char **)argv), &opt); + opt.output_format = DIFF_FORMAT_CALLBACK; + opt.format_callback = update_index_from_diff; + + index_fd = hold_locked_index(lock, 1); + read_cache(); + if (do_diff_cache(tree_sha1, &opt)) + return 1; + diffcore_std(&opt); + diff_flush(&opt); + return write_cache(index_fd, active_cache, active_nr) || + close(index_fd) || + commit_locked_index(lock); +} + +static void prepend_reflog_action(const char *action, char *buf, size_t size) +{ + const char *sep = ": "; + const char *rla = getenv("GIT_REFLOG_ACTION"); + if (!rla) + rla = sep = ""; + if (snprintf(buf, size, "%s%s%s", rla, sep, action) >= size) + warning("Reflog action message too long: %.*s...", 50, buf); +} + +enum reset_type { MIXED, SOFT, HARD, NONE }; +static char *reset_type_names[] = { "mixed", "soft", "hard", NULL }; + +int cmd_reset(int argc, const char **argv, const char *prefix) +{ + int i = 1, reset_type = NONE, update_ref_status = 0; + const char *rev = "HEAD"; + unsigned char sha1[20], *orig = NULL, sha1_orig[20], + *old_orig = NULL, sha1_old_orig[20]; + struct commit *commit; + char *reflog_action, msg[1024]; + + git_config(git_default_config); + + reflog_action = args_to_str(argv); + setenv("GIT_REFLOG_ACTION", reflog_action, 0); + + if (i < argc) { + if (!strcmp(argv[i], "--mixed")) { + reset_type = MIXED; + i++; + } + else if (!strcmp(argv[i], "--soft")) { + reset_type = SOFT; + i++; + } + else if (!strcmp(argv[i], "--hard")) { + reset_type = HARD; + i++; + } + } + + if (i < argc && argv[i][0] != '-') + rev = argv[i++]; + + if (get_sha1(rev, sha1)) + die("Failed to resolve '%s' as a valid ref.", rev); + + commit = lookup_commit_reference(sha1); + if (!commit) + die("Could not parse object '%s'.", rev); + hashcpy(sha1, commit->object.sha1); + + if (i < argc && !strcmp(argv[i], "--")) + i++; + else if (i < argc && argv[i][0] == '-') + usage(builtin_reset_usage); + + /* git reset tree [--] paths... can be used to + * load chosen paths from the tree into the index without + * affecting the working tree nor HEAD. */ + if (i < argc) { + if (reset_type == MIXED) + warning("--mixed option is deprecated with paths."); + else if (reset_type != NONE) + die("Cannot do %s reset with paths.", + reset_type_names[reset_type]); + if (read_from_tree(prefix, argv + i, sha1)) + return 1; + return update_index_refresh() ? 1 : 0; + } + if (reset_type == NONE) + reset_type = MIXED; /* by default */ + + /* Soft reset does not touch the index file nor the working tree + * at all, but requires them in a good order. Other resets reset + * the index file to the tree object we are switching to. */ + if (reset_type == SOFT) { + if (is_merge() || unmerged_files()) + die("Cannot do a soft reset in the middle of a merge."); + } + else if (reset_index_file(sha1, (reset_type == HARD))) + die("Could not reset index file to revision '%s'.", rev); + + /* Any resets update HEAD to the head being switched to, + * saving the previous head in ORIG_HEAD before. */ + if (!get_sha1("ORIG_HEAD", sha1_old_orig)) + old_orig = sha1_old_orig; + if (!get_sha1("HEAD", sha1_orig)) { + orig = sha1_orig; + prepend_reflog_action("updating ORIG_HEAD", msg, sizeof(msg)); + update_ref(msg, "ORIG_HEAD", orig, old_orig, 0, MSG_ON_ERR); + } + else if (old_orig) + delete_ref("ORIG_HEAD", old_orig); + prepend_reflog_action("updating HEAD", msg, sizeof(msg)); + update_ref_status = update_ref(msg, "HEAD", sha1, orig, 0, MSG_ON_ERR); + + switch (reset_type) { + case HARD: + if (!update_ref_status) + print_new_head_line(commit); + break; + case SOFT: /* Nothing else to do. */ + break; + case MIXED: /* Report what has not been updated. */ + update_index_refresh(); + break; + } + + unlink(git_path("MERGE_HEAD")); + unlink(git_path("rr-cache/MERGE_RR")); + unlink(git_path("MERGE_MSG")); + unlink(git_path("SQUASH_MSG")); + + free(reflog_action); + + return update_ref_status; +} |