From: Peter Eriksen Date: Tue, 23 May 2006 12:15:32 +0000 (+0200) Subject: Builtin git-read-tree. X-Git-Tag: v1.4.0-rc1~77^2~5 X-Git-Url: https://git.tokkee.org/?a=commitdiff_plain;h=d147e501f37a596e73a430ce46f125f83e06aa07;p=git.git Builtin git-read-tree. Signed-off-by: Peter Eriksen Signed-off-by: Junio C Hamano --- diff --git a/Makefile b/Makefile index a3164f8ef..1aebcf597 100644 --- a/Makefile +++ b/Makefile @@ -157,7 +157,7 @@ PROGRAMS = \ git-hash-object$X git-index-pack$X git-local-fetch$X \ git-mailinfo$X git-merge-base$X \ git-merge-index$X git-mktag$X git-mktree$X git-pack-objects$X git-patch-id$X \ - git-peek-remote$X git-prune-packed$X git-read-tree$X \ + git-peek-remote$X git-prune-packed$X \ git-receive-pack$X git-rev-parse$X \ git-send-pack$X git-show-branch$X git-shell$X \ git-show-index$X git-ssh-fetch$X \ @@ -172,7 +172,7 @@ BUILT_INS = git-log$X git-whatchanged$X git-show$X \ git-count-objects$X git-diff$X git-push$X \ git-grep$X git-rev-list$X git-check-ref-format$X \ git-init-db$X git-ls-files$X git-ls-tree$X \ - git-tar-tree$X + git-tar-tree$X git-read-tree$X # what 'all' will build and 'install' will install, in gitexecdir ALL_PROGRAMS = $(PROGRAMS) $(SIMPLE_PROGRAMS) $(SCRIPTS) @@ -222,7 +222,7 @@ BUILTIN_OBJS = \ builtin-log.o builtin-help.o builtin-count.o builtin-diff.o builtin-push.o \ builtin-grep.o builtin-rev-list.o builtin-check-ref-format.o \ builtin-init-db.o builtin-ls-files.o builtin-ls-tree.o \ - builtin-tar-tree.o + builtin-tar-tree.o builtin-read-tree.o GITLIBS = $(LIB_FILE) $(XDIFF_LIB) LIBS = $(GITLIBS) -lz diff --git a/builtin-read-tree.c b/builtin-read-tree.c new file mode 100644 index 000000000..ec40d013c --- /dev/null +++ b/builtin-read-tree.c @@ -0,0 +1,882 @@ +/* + * GIT - The information manager from hell + * + * Copyright (C) Linus Torvalds, 2005 + */ +#define DBRT_DEBUG 1 + +#include "cache.h" + +#include "object.h" +#include "tree.h" +#include +#include +#include "builtin.h" + +static int reset = 0; +static int merge = 0; +static int update = 0; +static int index_only = 0; +static int nontrivial_merge = 0; +static int trivial_merges_only = 0; +static int aggressive = 0; +static int verbose_update = 0; +static volatile int progress_update = 0; + +static int head_idx = -1; +static int merge_size = 0; + +static struct object_list *trees = NULL; + +static struct cache_entry df_conflict_entry = { +}; + +static struct tree_entry_list df_conflict_list = { + .name = NULL, + .next = &df_conflict_list +}; + +typedef int (*merge_fn_t)(struct cache_entry **src); + +static int entcmp(char *name1, int dir1, char *name2, int dir2) +{ + int len1 = strlen(name1); + int len2 = strlen(name2); + int len = len1 < len2 ? len1 : len2; + int ret = memcmp(name1, name2, len); + unsigned char c1, c2; + if (ret) + return ret; + c1 = name1[len]; + c2 = name2[len]; + if (!c1 && dir1) + c1 = '/'; + if (!c2 && dir2) + c2 = '/'; + ret = (c1 < c2) ? -1 : (c1 > c2) ? 1 : 0; + if (c1 && c2 && !ret) + ret = len1 - len2; + return ret; +} + +static int unpack_trees_rec(struct tree_entry_list **posns, int len, + const char *base, merge_fn_t fn, int *indpos) +{ + int baselen = strlen(base); + int src_size = len + 1; + do { + int i; + char *first; + int firstdir = 0; + int pathlen; + unsigned ce_size; + struct tree_entry_list **subposns; + struct cache_entry **src; + int any_files = 0; + int any_dirs = 0; + char *cache_name; + int ce_stage; + + /* Find the first name in the input. */ + + first = NULL; + cache_name = NULL; + + /* Check the cache */ + if (merge && *indpos < active_nr) { + /* This is a bit tricky: */ + /* If the index has a subdirectory (with + * contents) as the first name, it'll get a + * filename like "foo/bar". But that's after + * "foo", so the entry in trees will get + * handled first, at which point we'll go into + * "foo", and deal with "bar" from the index, + * because the base will be "foo/". The only + * way we can actually have "foo/bar" first of + * all the things is if the trees don't + * contain "foo" at all, in which case we'll + * handle "foo/bar" without going into the + * directory, but that's fine (and will return + * an error anyway, with the added unknown + * file case. + */ + + cache_name = active_cache[*indpos]->name; + if (strlen(cache_name) > baselen && + !memcmp(cache_name, base, baselen)) { + cache_name += baselen; + first = cache_name; + } else { + cache_name = NULL; + } + } + +#if DBRT_DEBUG > 1 + if (first) + printf("index %s\n", first); +#endif + for (i = 0; i < len; i++) { + if (!posns[i] || posns[i] == &df_conflict_list) + continue; +#if DBRT_DEBUG > 1 + printf("%d %s\n", i + 1, posns[i]->name); +#endif + if (!first || entcmp(first, firstdir, + posns[i]->name, + posns[i]->directory) > 0) { + first = posns[i]->name; + firstdir = posns[i]->directory; + } + } + /* No name means we're done */ + if (!first) + return 0; + + pathlen = strlen(first); + ce_size = cache_entry_size(baselen + pathlen); + + src = xcalloc(src_size, sizeof(struct cache_entry *)); + + subposns = xcalloc(len, sizeof(struct tree_list_entry *)); + + if (cache_name && !strcmp(cache_name, first)) { + any_files = 1; + src[0] = active_cache[*indpos]; + remove_cache_entry_at(*indpos); + } + + for (i = 0; i < len; i++) { + struct cache_entry *ce; + + if (!posns[i] || + (posns[i] != &df_conflict_list && + strcmp(first, posns[i]->name))) { + continue; + } + + if (posns[i] == &df_conflict_list) { + src[i + merge] = &df_conflict_entry; + continue; + } + + if (posns[i]->directory) { + any_dirs = 1; + parse_tree(posns[i]->item.tree); + subposns[i] = posns[i]->item.tree->entries; + posns[i] = posns[i]->next; + src[i + merge] = &df_conflict_entry; + continue; + } + + if (!merge) + ce_stage = 0; + else if (i + 1 < head_idx) + ce_stage = 1; + else if (i + 1 > head_idx) + ce_stage = 3; + else + ce_stage = 2; + + ce = xcalloc(1, ce_size); + ce->ce_mode = create_ce_mode(posns[i]->mode); + ce->ce_flags = create_ce_flags(baselen + pathlen, + ce_stage); + memcpy(ce->name, base, baselen); + memcpy(ce->name + baselen, first, pathlen + 1); + + any_files = 1; + + memcpy(ce->sha1, posns[i]->item.any->sha1, 20); + src[i + merge] = ce; + subposns[i] = &df_conflict_list; + posns[i] = posns[i]->next; + } + if (any_files) { + if (merge) { + int ret; + +#if DBRT_DEBUG > 1 + printf("%s:\n", first); + for (i = 0; i < src_size; i++) { + printf(" %d ", i); + if (src[i]) + printf("%s\n", sha1_to_hex(src[i]->sha1)); + else + printf("\n"); + } +#endif + ret = fn(src); + +#if DBRT_DEBUG > 1 + printf("Added %d entries\n", ret); +#endif + *indpos += ret; + } else { + for (i = 0; i < src_size; i++) { + if (src[i]) { + add_cache_entry(src[i], ADD_CACHE_OK_TO_ADD|ADD_CACHE_SKIP_DFCHECK); + } + } + } + } + if (any_dirs) { + char *newbase = xmalloc(baselen + 2 + pathlen); + memcpy(newbase, base, baselen); + memcpy(newbase + baselen, first, pathlen); + newbase[baselen + pathlen] = '/'; + newbase[baselen + pathlen + 1] = '\0'; + if (unpack_trees_rec(subposns, len, newbase, fn, + indpos)) + return -1; + free(newbase); + } + free(subposns); + free(src); + } while (1); +} + +static void reject_merge(struct cache_entry *ce) +{ + die("Entry '%s' would be overwritten by merge. Cannot merge.", + ce->name); +} + +/* Unlink the last component and attempt to remove leading + * directories, in case this unlink is the removal of the + * last entry in the directory -- empty directories are removed. + */ +static void unlink_entry(char *name) +{ + char *cp, *prev; + + if (unlink(name)) + return; + prev = NULL; + while (1) { + int status; + cp = strrchr(name, '/'); + if (prev) + *prev = '/'; + if (!cp) + break; + + *cp = 0; + status = rmdir(name); + if (status) { + *cp = '/'; + break; + } + prev = cp; + } +} + +static void progress_interval(int signum) +{ + progress_update = 1; +} + +static void setup_progress_signal(void) +{ + struct sigaction sa; + struct itimerval v; + + memset(&sa, 0, sizeof(sa)); + sa.sa_handler = progress_interval; + sigemptyset(&sa.sa_mask); + sa.sa_flags = SA_RESTART; + sigaction(SIGALRM, &sa, NULL); + + v.it_interval.tv_sec = 1; + v.it_interval.tv_usec = 0; + v.it_value = v.it_interval; + setitimer(ITIMER_REAL, &v, NULL); +} + +static void check_updates(struct cache_entry **src, int nr) +{ + static struct checkout state = { + .base_dir = "", + .force = 1, + .quiet = 1, + .refresh_cache = 1, + }; + unsigned short mask = htons(CE_UPDATE); + unsigned last_percent = 200, cnt = 0, total = 0; + + if (update && verbose_update) { + for (total = cnt = 0; cnt < nr; cnt++) { + struct cache_entry *ce = src[cnt]; + if (!ce->ce_mode || ce->ce_flags & mask) + total++; + } + + /* Don't bother doing this for very small updates */ + if (total < 250) + total = 0; + + if (total) { + fprintf(stderr, "Checking files out...\n"); + setup_progress_signal(); + progress_update = 1; + } + cnt = 0; + } + + while (nr--) { + struct cache_entry *ce = *src++; + + if (total) { + if (!ce->ce_mode || ce->ce_flags & mask) { + unsigned percent; + cnt++; + percent = (cnt * 100) / total; + if (percent != last_percent || + progress_update) { + fprintf(stderr, "%4u%% (%u/%u) done\r", + percent, cnt, total); + last_percent = percent; + } + } + } + if (!ce->ce_mode) { + if (update) + unlink_entry(ce->name); + continue; + } + if (ce->ce_flags & mask) { + ce->ce_flags &= ~mask; + if (update) + checkout_entry(ce, &state, NULL); + } + } + if (total) { + signal(SIGALRM, SIG_IGN); + fputc('\n', stderr); + } +} + +static int unpack_trees(merge_fn_t fn) +{ + int indpos = 0; + unsigned len = object_list_length(trees); + struct tree_entry_list **posns; + int i; + struct object_list *posn = trees; + merge_size = len; + + if (len) { + posns = xmalloc(len * sizeof(struct tree_entry_list *)); + for (i = 0; i < len; i++) { + posns[i] = ((struct tree *) posn->item)->entries; + posn = posn->next; + } + if (unpack_trees_rec(posns, len, "", fn, &indpos)) + return -1; + } + + if (trivial_merges_only && nontrivial_merge) + die("Merge requires file-level merging"); + + check_updates(active_cache, active_nr); + return 0; +} + +static int list_tree(unsigned char *sha1) +{ + struct tree *tree = parse_tree_indirect(sha1); + if (!tree) + return -1; + object_list_append(&tree->object, &trees); + return 0; +} + +static int same(struct cache_entry *a, struct cache_entry *b) +{ + if (!!a != !!b) + return 0; + if (!a && !b) + return 1; + return a->ce_mode == b->ce_mode && + !memcmp(a->sha1, b->sha1, 20); +} + + +/* + * When a CE gets turned into an unmerged entry, we + * want it to be up-to-date + */ +static void verify_uptodate(struct cache_entry *ce) +{ + struct stat st; + + if (index_only || reset) + return; + + if (!lstat(ce->name, &st)) { + unsigned changed = ce_match_stat(ce, &st, 1); + if (!changed) + return; + errno = 0; + } + if (reset) { + ce->ce_flags |= htons(CE_UPDATE); + return; + } + if (errno == ENOENT) + return; + die("Entry '%s' not uptodate. Cannot merge.", ce->name); +} + +/* + * We do not want to remove or overwrite a working tree file that + * is not tracked. + */ +static void verify_absent(const char *path, const char *action) +{ + struct stat st; + + if (index_only || reset || !update) + return; + if (!lstat(path, &st)) + die("Untracked working tree file '%s' " + "would be %s by merge.", path, action); +} + +static int merged_entry(struct cache_entry *merge, struct cache_entry *old) +{ + merge->ce_flags |= htons(CE_UPDATE); + if (old) { + /* + * See if we can re-use the old CE directly? + * That way we get the uptodate stat info. + * + * This also removes the UPDATE flag on + * a match. + */ + if (same(old, merge)) { + *merge = *old; + } else { + verify_uptodate(old); + } + } + else + verify_absent(merge->name, "overwritten"); + + merge->ce_flags &= ~htons(CE_STAGEMASK); + add_cache_entry(merge, ADD_CACHE_OK_TO_ADD); + return 1; +} + +static int deleted_entry(struct cache_entry *ce, struct cache_entry *old) +{ + if (old) + verify_uptodate(old); + else + verify_absent(ce->name, "removed"); + ce->ce_mode = 0; + add_cache_entry(ce, ADD_CACHE_OK_TO_ADD); + return 1; +} + +static int keep_entry(struct cache_entry *ce) +{ + add_cache_entry(ce, ADD_CACHE_OK_TO_ADD); + return 1; +} + +#if DBRT_DEBUG +static void show_stage_entry(FILE *o, + const char *label, const struct cache_entry *ce) +{ + if (!ce) + fprintf(o, "%s (missing)\n", label); + else + fprintf(o, "%s%06o %s %d\t%s\n", + label, + ntohl(ce->ce_mode), + sha1_to_hex(ce->sha1), + ce_stage(ce), + ce->name); +} +#endif + +static int threeway_merge(struct cache_entry **stages) +{ + struct cache_entry *index; + struct cache_entry *head; + struct cache_entry *remote = stages[head_idx + 1]; + int count; + int head_match = 0; + int remote_match = 0; + const char *path = NULL; + + int df_conflict_head = 0; + int df_conflict_remote = 0; + + int any_anc_missing = 0; + int no_anc_exists = 1; + int i; + + for (i = 1; i < head_idx; i++) { + if (!stages[i]) + any_anc_missing = 1; + else { + if (!path) + path = stages[i]->name; + no_anc_exists = 0; + } + } + + index = stages[0]; + head = stages[head_idx]; + + if (head == &df_conflict_entry) { + df_conflict_head = 1; + head = NULL; + } + + if (remote == &df_conflict_entry) { + df_conflict_remote = 1; + remote = NULL; + } + + if (!path && index) + path = index->name; + if (!path && head) + path = head->name; + if (!path && remote) + path = remote->name; + + /* First, if there's a #16 situation, note that to prevent #13 + * and #14. + */ + if (!same(remote, head)) { + for (i = 1; i < head_idx; i++) { + if (same(stages[i], head)) { + head_match = i; + } + if (same(stages[i], remote)) { + remote_match = i; + } + } + } + + /* We start with cases where the index is allowed to match + * something other than the head: #14(ALT) and #2ALT, where it + * is permitted to match the result instead. + */ + /* #14, #14ALT, #2ALT */ + if (remote && !df_conflict_head && head_match && !remote_match) { + if (index && !same(index, remote) && !same(index, head)) + reject_merge(index); + return merged_entry(remote, index); + } + /* + * If we have an entry in the index cache, then we want to + * make sure that it matches head. + */ + if (index && !same(index, head)) { + reject_merge(index); + } + + if (head) { + /* #5ALT, #15 */ + if (same(head, remote)) + return merged_entry(head, index); + /* #13, #3ALT */ + if (!df_conflict_remote && remote_match && !head_match) + return merged_entry(head, index); + } + + /* #1 */ + if (!head && !remote && any_anc_missing) + return 0; + + /* Under the new "aggressive" rule, we resolve mostly trivial + * cases that we historically had git-merge-one-file resolve. + */ + if (aggressive) { + int head_deleted = !head && !df_conflict_head; + int remote_deleted = !remote && !df_conflict_remote; + /* + * Deleted in both. + * Deleted in one and unchanged in the other. + */ + if ((head_deleted && remote_deleted) || + (head_deleted && remote && remote_match) || + (remote_deleted && head && head_match)) { + if (index) + return deleted_entry(index, index); + else if (path) + verify_absent(path, "removed"); + return 0; + } + /* + * Added in both, identically. + */ + if (no_anc_exists && head && remote && same(head, remote)) + return merged_entry(head, index); + + } + + /* Below are "no merge" cases, which require that the index be + * up-to-date to avoid the files getting overwritten with + * conflict resolution files. + */ + if (index) { + verify_uptodate(index); + } + else if (path) + verify_absent(path, "overwritten"); + + nontrivial_merge = 1; + + /* #2, #3, #4, #6, #7, #9, #11. */ + count = 0; + if (!head_match || !remote_match) { + for (i = 1; i < head_idx; i++) { + if (stages[i]) { + keep_entry(stages[i]); + count++; + break; + } + } + } +#if DBRT_DEBUG + else { + fprintf(stderr, "read-tree: warning #16 detected\n"); + show_stage_entry(stderr, "head ", stages[head_match]); + show_stage_entry(stderr, "remote ", stages[remote_match]); + } +#endif + if (head) { count += keep_entry(head); } + if (remote) { count += keep_entry(remote); } + return count; +} + +/* + * Two-way merge. + * + * The rule is to "carry forward" what is in the index without losing + * information across a "fast forward", favoring a successful merge + * over a merge failure when it makes sense. For details of the + * "carry forward" rule, please see . + * + */ +static int twoway_merge(struct cache_entry **src) +{ + struct cache_entry *current = src[0]; + struct cache_entry *oldtree = src[1], *newtree = src[2]; + + if (merge_size != 2) + return error("Cannot do a twoway merge of %d trees", + merge_size); + + if (current) { + if ((!oldtree && !newtree) || /* 4 and 5 */ + (!oldtree && newtree && + same(current, newtree)) || /* 6 and 7 */ + (oldtree && newtree && + same(oldtree, newtree)) || /* 14 and 15 */ + (oldtree && newtree && + !same(oldtree, newtree) && /* 18 and 19*/ + same(current, newtree))) { + return keep_entry(current); + } + else if (oldtree && !newtree && same(current, oldtree)) { + /* 10 or 11 */ + return deleted_entry(oldtree, current); + } + else if (oldtree && newtree && + same(current, oldtree) && !same(current, newtree)) { + /* 20 or 21 */ + return merged_entry(newtree, current); + } + else { + /* all other failures */ + if (oldtree) + reject_merge(oldtree); + if (current) + reject_merge(current); + if (newtree) + reject_merge(newtree); + return -1; + } + } + else if (newtree) + return merged_entry(newtree, current); + else + return deleted_entry(oldtree, current); +} + +/* + * One-way merge. + * + * The rule is: + * - take the stat information from stage0, take the data from stage1 + */ +static int oneway_merge(struct cache_entry **src) +{ + struct cache_entry *old = src[0]; + struct cache_entry *a = src[1]; + + if (merge_size != 1) + return error("Cannot do a oneway merge of %d trees", + merge_size); + + if (!a) + return deleted_entry(old, old); + if (old && same(old, a)) { + if (reset) { + struct stat st; + if (lstat(old->name, &st) || + ce_match_stat(old, &st, 1)) + old->ce_flags |= htons(CE_UPDATE); + } + return keep_entry(old); + } + return merged_entry(a, old); +} + +static int read_cache_unmerged(void) +{ + int i, deleted; + struct cache_entry **dst; + + read_cache(); + dst = active_cache; + deleted = 0; + for (i = 0; i < active_nr; i++) { + struct cache_entry *ce = active_cache[i]; + if (ce_stage(ce)) { + deleted++; + continue; + } + if (deleted) + *dst = ce; + dst++; + } + active_nr -= deleted; + return deleted; +} + +static const char read_tree_usage[] = "git-read-tree ( | -m [--aggressive] [-u | -i] [ []])"; + +static struct cache_file cache_file; + +int cmd_read_tree(int argc, const char **argv, char **envp) +{ + int i, newfd, stage = 0; + unsigned char sha1[20]; + merge_fn_t fn = NULL; + + setup_git_directory(); + git_config(git_default_config); + + newfd = hold_index_file_for_update(&cache_file, get_index_file()); + if (newfd < 0) + die("unable to create new cachefile"); + + git_config(git_default_config); + + merge = 0; + reset = 0; + for (i = 1; i < argc; i++) { + const char *arg = argv[i]; + + /* "-u" means "update", meaning that a merge will update + * the working tree. + */ + if (!strcmp(arg, "-u")) { + update = 1; + continue; + } + + if (!strcmp(arg, "-v")) { + verbose_update = 1; + continue; + } + + /* "-i" means "index only", meaning that a merge will + * not even look at the working tree. + */ + if (!strcmp(arg, "-i")) { + index_only = 1; + continue; + } + + /* This differs from "-m" in that we'll silently ignore unmerged entries */ + if (!strcmp(arg, "--reset")) { + if (stage || merge) + usage(read_tree_usage); + reset = 1; + merge = 1; + stage = 1; + read_cache_unmerged(); + continue; + } + + if (!strcmp(arg, "--trivial")) { + trivial_merges_only = 1; + continue; + } + + if (!strcmp(arg, "--aggressive")) { + aggressive = 1; + continue; + } + + /* "-m" stands for "merge", meaning we start in stage 1 */ + if (!strcmp(arg, "-m")) { + if (stage || merge) + usage(read_tree_usage); + if (read_cache_unmerged()) + die("you need to resolve your current index first"); + stage = 1; + merge = 1; + continue; + } + + /* using -u and -i at the same time makes no sense */ + if (1 < index_only + update) + usage(read_tree_usage); + + if (get_sha1(arg, sha1)) + die("Not a valid object name %s", arg); + if (list_tree(sha1) < 0) + die("failed to unpack tree object %s", arg); + stage++; + } + if ((update||index_only) && !merge) + usage(read_tree_usage); + + if (merge) { + if (stage < 2) + die("just how do you expect me to merge %d trees?", stage-1); + switch (stage - 1) { + case 1: + fn = oneway_merge; + break; + case 2: + fn = twoway_merge; + break; + case 3: + fn = threeway_merge; + break; + default: + fn = threeway_merge; + break; + } + + if (stage - 1 >= 3) + head_idx = stage - 2; + else + head_idx = 1; + } + + unpack_trees(fn); + if (write_cache(newfd, active_cache, active_nr) || + commit_index_file(&cache_file)) + die("unable to write new index file"); + return 0; +} diff --git a/builtin.h b/builtin.h index d21054394..88b3523c2 100644 --- a/builtin.h +++ b/builtin.h @@ -30,5 +30,6 @@ extern int cmd_init_db(int argc, const char **argv, char **envp); extern int cmd_ls_files(int argc, const char **argv, char **envp); extern int cmd_ls_tree(int argc, const char **argv, char **envp); extern int cmd_tar_tree(int argc, const char **argv, char **envp); +extern int cmd_read_tree(int argc, const char **argv, char **envp); #endif diff --git a/git.c b/git.c index c253e6095..300e2b269 100644 --- a/git.c +++ b/git.c @@ -55,7 +55,8 @@ static void handle_internal_command(int argc, const char **argv, char **envp) { "check-ref-format", cmd_check_ref_format }, { "ls-files", cmd_ls_files }, { "ls-tree", cmd_ls_tree }, - { "tar-tree", cmd_tar_tree } + { "tar-tree", cmd_tar_tree }, + { "read-tree", cmd_read_tree } }; int i; diff --git a/read-tree.c b/read-tree.c deleted file mode 100644 index 82e2a9a4d..000000000 --- a/read-tree.c +++ /dev/null @@ -1,881 +0,0 @@ -/* - * GIT - The information manager from hell - * - * Copyright (C) Linus Torvalds, 2005 - */ -#define DBRT_DEBUG 1 - -#include "cache.h" - -#include "object.h" -#include "tree.h" -#include -#include - -static int reset = 0; -static int merge = 0; -static int update = 0; -static int index_only = 0; -static int nontrivial_merge = 0; -static int trivial_merges_only = 0; -static int aggressive = 0; -static int verbose_update = 0; -static volatile int progress_update = 0; - -static int head_idx = -1; -static int merge_size = 0; - -static struct object_list *trees = NULL; - -static struct cache_entry df_conflict_entry = { -}; - -static struct tree_entry_list df_conflict_list = { - .name = NULL, - .next = &df_conflict_list -}; - -typedef int (*merge_fn_t)(struct cache_entry **src); - -static int entcmp(char *name1, int dir1, char *name2, int dir2) -{ - int len1 = strlen(name1); - int len2 = strlen(name2); - int len = len1 < len2 ? len1 : len2; - int ret = memcmp(name1, name2, len); - unsigned char c1, c2; - if (ret) - return ret; - c1 = name1[len]; - c2 = name2[len]; - if (!c1 && dir1) - c1 = '/'; - if (!c2 && dir2) - c2 = '/'; - ret = (c1 < c2) ? -1 : (c1 > c2) ? 1 : 0; - if (c1 && c2 && !ret) - ret = len1 - len2; - return ret; -} - -static int unpack_trees_rec(struct tree_entry_list **posns, int len, - const char *base, merge_fn_t fn, int *indpos) -{ - int baselen = strlen(base); - int src_size = len + 1; - do { - int i; - char *first; - int firstdir = 0; - int pathlen; - unsigned ce_size; - struct tree_entry_list **subposns; - struct cache_entry **src; - int any_files = 0; - int any_dirs = 0; - char *cache_name; - int ce_stage; - - /* Find the first name in the input. */ - - first = NULL; - cache_name = NULL; - - /* Check the cache */ - if (merge && *indpos < active_nr) { - /* This is a bit tricky: */ - /* If the index has a subdirectory (with - * contents) as the first name, it'll get a - * filename like "foo/bar". But that's after - * "foo", so the entry in trees will get - * handled first, at which point we'll go into - * "foo", and deal with "bar" from the index, - * because the base will be "foo/". The only - * way we can actually have "foo/bar" first of - * all the things is if the trees don't - * contain "foo" at all, in which case we'll - * handle "foo/bar" without going into the - * directory, but that's fine (and will return - * an error anyway, with the added unknown - * file case. - */ - - cache_name = active_cache[*indpos]->name; - if (strlen(cache_name) > baselen && - !memcmp(cache_name, base, baselen)) { - cache_name += baselen; - first = cache_name; - } else { - cache_name = NULL; - } - } - -#if DBRT_DEBUG > 1 - if (first) - printf("index %s\n", first); -#endif - for (i = 0; i < len; i++) { - if (!posns[i] || posns[i] == &df_conflict_list) - continue; -#if DBRT_DEBUG > 1 - printf("%d %s\n", i + 1, posns[i]->name); -#endif - if (!first || entcmp(first, firstdir, - posns[i]->name, - posns[i]->directory) > 0) { - first = posns[i]->name; - firstdir = posns[i]->directory; - } - } - /* No name means we're done */ - if (!first) - return 0; - - pathlen = strlen(first); - ce_size = cache_entry_size(baselen + pathlen); - - src = xcalloc(src_size, sizeof(struct cache_entry *)); - - subposns = xcalloc(len, sizeof(struct tree_list_entry *)); - - if (cache_name && !strcmp(cache_name, first)) { - any_files = 1; - src[0] = active_cache[*indpos]; - remove_cache_entry_at(*indpos); - } - - for (i = 0; i < len; i++) { - struct cache_entry *ce; - - if (!posns[i] || - (posns[i] != &df_conflict_list && - strcmp(first, posns[i]->name))) { - continue; - } - - if (posns[i] == &df_conflict_list) { - src[i + merge] = &df_conflict_entry; - continue; - } - - if (posns[i]->directory) { - any_dirs = 1; - parse_tree(posns[i]->item.tree); - subposns[i] = posns[i]->item.tree->entries; - posns[i] = posns[i]->next; - src[i + merge] = &df_conflict_entry; - continue; - } - - if (!merge) - ce_stage = 0; - else if (i + 1 < head_idx) - ce_stage = 1; - else if (i + 1 > head_idx) - ce_stage = 3; - else - ce_stage = 2; - - ce = xcalloc(1, ce_size); - ce->ce_mode = create_ce_mode(posns[i]->mode); - ce->ce_flags = create_ce_flags(baselen + pathlen, - ce_stage); - memcpy(ce->name, base, baselen); - memcpy(ce->name + baselen, first, pathlen + 1); - - any_files = 1; - - memcpy(ce->sha1, posns[i]->item.any->sha1, 20); - src[i + merge] = ce; - subposns[i] = &df_conflict_list; - posns[i] = posns[i]->next; - } - if (any_files) { - if (merge) { - int ret; - -#if DBRT_DEBUG > 1 - printf("%s:\n", first); - for (i = 0; i < src_size; i++) { - printf(" %d ", i); - if (src[i]) - printf("%s\n", sha1_to_hex(src[i]->sha1)); - else - printf("\n"); - } -#endif - ret = fn(src); - -#if DBRT_DEBUG > 1 - printf("Added %d entries\n", ret); -#endif - *indpos += ret; - } else { - for (i = 0; i < src_size; i++) { - if (src[i]) { - add_cache_entry(src[i], ADD_CACHE_OK_TO_ADD|ADD_CACHE_SKIP_DFCHECK); - } - } - } - } - if (any_dirs) { - char *newbase = xmalloc(baselen + 2 + pathlen); - memcpy(newbase, base, baselen); - memcpy(newbase + baselen, first, pathlen); - newbase[baselen + pathlen] = '/'; - newbase[baselen + pathlen + 1] = '\0'; - if (unpack_trees_rec(subposns, len, newbase, fn, - indpos)) - return -1; - free(newbase); - } - free(subposns); - free(src); - } while (1); -} - -static void reject_merge(struct cache_entry *ce) -{ - die("Entry '%s' would be overwritten by merge. Cannot merge.", - ce->name); -} - -/* Unlink the last component and attempt to remove leading - * directories, in case this unlink is the removal of the - * last entry in the directory -- empty directories are removed. - */ -static void unlink_entry(char *name) -{ - char *cp, *prev; - - if (unlink(name)) - return; - prev = NULL; - while (1) { - int status; - cp = strrchr(name, '/'); - if (prev) - *prev = '/'; - if (!cp) - break; - - *cp = 0; - status = rmdir(name); - if (status) { - *cp = '/'; - break; - } - prev = cp; - } -} - -static void progress_interval(int signum) -{ - progress_update = 1; -} - -static void setup_progress_signal(void) -{ - struct sigaction sa; - struct itimerval v; - - memset(&sa, 0, sizeof(sa)); - sa.sa_handler = progress_interval; - sigemptyset(&sa.sa_mask); - sa.sa_flags = SA_RESTART; - sigaction(SIGALRM, &sa, NULL); - - v.it_interval.tv_sec = 1; - v.it_interval.tv_usec = 0; - v.it_value = v.it_interval; - setitimer(ITIMER_REAL, &v, NULL); -} - -static void check_updates(struct cache_entry **src, int nr) -{ - static struct checkout state = { - .base_dir = "", - .force = 1, - .quiet = 1, - .refresh_cache = 1, - }; - unsigned short mask = htons(CE_UPDATE); - unsigned last_percent = 200, cnt = 0, total = 0; - - if (update && verbose_update) { - for (total = cnt = 0; cnt < nr; cnt++) { - struct cache_entry *ce = src[cnt]; - if (!ce->ce_mode || ce->ce_flags & mask) - total++; - } - - /* Don't bother doing this for very small updates */ - if (total < 250) - total = 0; - - if (total) { - fprintf(stderr, "Checking files out...\n"); - setup_progress_signal(); - progress_update = 1; - } - cnt = 0; - } - - while (nr--) { - struct cache_entry *ce = *src++; - - if (total) { - if (!ce->ce_mode || ce->ce_flags & mask) { - unsigned percent; - cnt++; - percent = (cnt * 100) / total; - if (percent != last_percent || - progress_update) { - fprintf(stderr, "%4u%% (%u/%u) done\r", - percent, cnt, total); - last_percent = percent; - } - } - } - if (!ce->ce_mode) { - if (update) - unlink_entry(ce->name); - continue; - } - if (ce->ce_flags & mask) { - ce->ce_flags &= ~mask; - if (update) - checkout_entry(ce, &state, NULL); - } - } - if (total) { - signal(SIGALRM, SIG_IGN); - fputc('\n', stderr); - } -} - -static int unpack_trees(merge_fn_t fn) -{ - int indpos = 0; - unsigned len = object_list_length(trees); - struct tree_entry_list **posns; - int i; - struct object_list *posn = trees; - merge_size = len; - - if (len) { - posns = xmalloc(len * sizeof(struct tree_entry_list *)); - for (i = 0; i < len; i++) { - posns[i] = ((struct tree *) posn->item)->entries; - posn = posn->next; - } - if (unpack_trees_rec(posns, len, "", fn, &indpos)) - return -1; - } - - if (trivial_merges_only && nontrivial_merge) - die("Merge requires file-level merging"); - - check_updates(active_cache, active_nr); - return 0; -} - -static int list_tree(unsigned char *sha1) -{ - struct tree *tree = parse_tree_indirect(sha1); - if (!tree) - return -1; - object_list_append(&tree->object, &trees); - return 0; -} - -static int same(struct cache_entry *a, struct cache_entry *b) -{ - if (!!a != !!b) - return 0; - if (!a && !b) - return 1; - return a->ce_mode == b->ce_mode && - !memcmp(a->sha1, b->sha1, 20); -} - - -/* - * When a CE gets turned into an unmerged entry, we - * want it to be up-to-date - */ -static void verify_uptodate(struct cache_entry *ce) -{ - struct stat st; - - if (index_only || reset) - return; - - if (!lstat(ce->name, &st)) { - unsigned changed = ce_match_stat(ce, &st, 1); - if (!changed) - return; - errno = 0; - } - if (reset) { - ce->ce_flags |= htons(CE_UPDATE); - return; - } - if (errno == ENOENT) - return; - die("Entry '%s' not uptodate. Cannot merge.", ce->name); -} - -/* - * We do not want to remove or overwrite a working tree file that - * is not tracked. - */ -static void verify_absent(const char *path, const char *action) -{ - struct stat st; - - if (index_only || reset || !update) - return; - if (!lstat(path, &st)) - die("Untracked working tree file '%s' " - "would be %s by merge.", path, action); -} - -static int merged_entry(struct cache_entry *merge, struct cache_entry *old) -{ - merge->ce_flags |= htons(CE_UPDATE); - if (old) { - /* - * See if we can re-use the old CE directly? - * That way we get the uptodate stat info. - * - * This also removes the UPDATE flag on - * a match. - */ - if (same(old, merge)) { - *merge = *old; - } else { - verify_uptodate(old); - } - } - else - verify_absent(merge->name, "overwritten"); - - merge->ce_flags &= ~htons(CE_STAGEMASK); - add_cache_entry(merge, ADD_CACHE_OK_TO_ADD); - return 1; -} - -static int deleted_entry(struct cache_entry *ce, struct cache_entry *old) -{ - if (old) - verify_uptodate(old); - else - verify_absent(ce->name, "removed"); - ce->ce_mode = 0; - add_cache_entry(ce, ADD_CACHE_OK_TO_ADD); - return 1; -} - -static int keep_entry(struct cache_entry *ce) -{ - add_cache_entry(ce, ADD_CACHE_OK_TO_ADD); - return 1; -} - -#if DBRT_DEBUG -static void show_stage_entry(FILE *o, - const char *label, const struct cache_entry *ce) -{ - if (!ce) - fprintf(o, "%s (missing)\n", label); - else - fprintf(o, "%s%06o %s %d\t%s\n", - label, - ntohl(ce->ce_mode), - sha1_to_hex(ce->sha1), - ce_stage(ce), - ce->name); -} -#endif - -static int threeway_merge(struct cache_entry **stages) -{ - struct cache_entry *index; - struct cache_entry *head; - struct cache_entry *remote = stages[head_idx + 1]; - int count; - int head_match = 0; - int remote_match = 0; - const char *path = NULL; - - int df_conflict_head = 0; - int df_conflict_remote = 0; - - int any_anc_missing = 0; - int no_anc_exists = 1; - int i; - - for (i = 1; i < head_idx; i++) { - if (!stages[i]) - any_anc_missing = 1; - else { - if (!path) - path = stages[i]->name; - no_anc_exists = 0; - } - } - - index = stages[0]; - head = stages[head_idx]; - - if (head == &df_conflict_entry) { - df_conflict_head = 1; - head = NULL; - } - - if (remote == &df_conflict_entry) { - df_conflict_remote = 1; - remote = NULL; - } - - if (!path && index) - path = index->name; - if (!path && head) - path = head->name; - if (!path && remote) - path = remote->name; - - /* First, if there's a #16 situation, note that to prevent #13 - * and #14. - */ - if (!same(remote, head)) { - for (i = 1; i < head_idx; i++) { - if (same(stages[i], head)) { - head_match = i; - } - if (same(stages[i], remote)) { - remote_match = i; - } - } - } - - /* We start with cases where the index is allowed to match - * something other than the head: #14(ALT) and #2ALT, where it - * is permitted to match the result instead. - */ - /* #14, #14ALT, #2ALT */ - if (remote && !df_conflict_head && head_match && !remote_match) { - if (index && !same(index, remote) && !same(index, head)) - reject_merge(index); - return merged_entry(remote, index); - } - /* - * If we have an entry in the index cache, then we want to - * make sure that it matches head. - */ - if (index && !same(index, head)) { - reject_merge(index); - } - - if (head) { - /* #5ALT, #15 */ - if (same(head, remote)) - return merged_entry(head, index); - /* #13, #3ALT */ - if (!df_conflict_remote && remote_match && !head_match) - return merged_entry(head, index); - } - - /* #1 */ - if (!head && !remote && any_anc_missing) - return 0; - - /* Under the new "aggressive" rule, we resolve mostly trivial - * cases that we historically had git-merge-one-file resolve. - */ - if (aggressive) { - int head_deleted = !head && !df_conflict_head; - int remote_deleted = !remote && !df_conflict_remote; - /* - * Deleted in both. - * Deleted in one and unchanged in the other. - */ - if ((head_deleted && remote_deleted) || - (head_deleted && remote && remote_match) || - (remote_deleted && head && head_match)) { - if (index) - return deleted_entry(index, index); - else if (path) - verify_absent(path, "removed"); - return 0; - } - /* - * Added in both, identically. - */ - if (no_anc_exists && head && remote && same(head, remote)) - return merged_entry(head, index); - - } - - /* Below are "no merge" cases, which require that the index be - * up-to-date to avoid the files getting overwritten with - * conflict resolution files. - */ - if (index) { - verify_uptodate(index); - } - else if (path) - verify_absent(path, "overwritten"); - - nontrivial_merge = 1; - - /* #2, #3, #4, #6, #7, #9, #11. */ - count = 0; - if (!head_match || !remote_match) { - for (i = 1; i < head_idx; i++) { - if (stages[i]) { - keep_entry(stages[i]); - count++; - break; - } - } - } -#if DBRT_DEBUG - else { - fprintf(stderr, "read-tree: warning #16 detected\n"); - show_stage_entry(stderr, "head ", stages[head_match]); - show_stage_entry(stderr, "remote ", stages[remote_match]); - } -#endif - if (head) { count += keep_entry(head); } - if (remote) { count += keep_entry(remote); } - return count; -} - -/* - * Two-way merge. - * - * The rule is to "carry forward" what is in the index without losing - * information across a "fast forward", favoring a successful merge - * over a merge failure when it makes sense. For details of the - * "carry forward" rule, please see . - * - */ -static int twoway_merge(struct cache_entry **src) -{ - struct cache_entry *current = src[0]; - struct cache_entry *oldtree = src[1], *newtree = src[2]; - - if (merge_size != 2) - return error("Cannot do a twoway merge of %d trees", - merge_size); - - if (current) { - if ((!oldtree && !newtree) || /* 4 and 5 */ - (!oldtree && newtree && - same(current, newtree)) || /* 6 and 7 */ - (oldtree && newtree && - same(oldtree, newtree)) || /* 14 and 15 */ - (oldtree && newtree && - !same(oldtree, newtree) && /* 18 and 19*/ - same(current, newtree))) { - return keep_entry(current); - } - else if (oldtree && !newtree && same(current, oldtree)) { - /* 10 or 11 */ - return deleted_entry(oldtree, current); - } - else if (oldtree && newtree && - same(current, oldtree) && !same(current, newtree)) { - /* 20 or 21 */ - return merged_entry(newtree, current); - } - else { - /* all other failures */ - if (oldtree) - reject_merge(oldtree); - if (current) - reject_merge(current); - if (newtree) - reject_merge(newtree); - return -1; - } - } - else if (newtree) - return merged_entry(newtree, current); - else - return deleted_entry(oldtree, current); -} - -/* - * One-way merge. - * - * The rule is: - * - take the stat information from stage0, take the data from stage1 - */ -static int oneway_merge(struct cache_entry **src) -{ - struct cache_entry *old = src[0]; - struct cache_entry *a = src[1]; - - if (merge_size != 1) - return error("Cannot do a oneway merge of %d trees", - merge_size); - - if (!a) - return deleted_entry(old, old); - if (old && same(old, a)) { - if (reset) { - struct stat st; - if (lstat(old->name, &st) || - ce_match_stat(old, &st, 1)) - old->ce_flags |= htons(CE_UPDATE); - } - return keep_entry(old); - } - return merged_entry(a, old); -} - -static int read_cache_unmerged(void) -{ - int i, deleted; - struct cache_entry **dst; - - read_cache(); - dst = active_cache; - deleted = 0; - for (i = 0; i < active_nr; i++) { - struct cache_entry *ce = active_cache[i]; - if (ce_stage(ce)) { - deleted++; - continue; - } - if (deleted) - *dst = ce; - dst++; - } - active_nr -= deleted; - return deleted; -} - -static const char read_tree_usage[] = "git-read-tree ( | -m [--aggressive] [-u | -i] [ []])"; - -static struct cache_file cache_file; - -int main(int argc, char **argv) -{ - int i, newfd, stage = 0; - unsigned char sha1[20]; - merge_fn_t fn = NULL; - - setup_git_directory(); - git_config(git_default_config); - - newfd = hold_index_file_for_update(&cache_file, get_index_file()); - if (newfd < 0) - die("unable to create new cachefile"); - - git_config(git_default_config); - - merge = 0; - reset = 0; - for (i = 1; i < argc; i++) { - const char *arg = argv[i]; - - /* "-u" means "update", meaning that a merge will update - * the working tree. - */ - if (!strcmp(arg, "-u")) { - update = 1; - continue; - } - - if (!strcmp(arg, "-v")) { - verbose_update = 1; - continue; - } - - /* "-i" means "index only", meaning that a merge will - * not even look at the working tree. - */ - if (!strcmp(arg, "-i")) { - index_only = 1; - continue; - } - - /* This differs from "-m" in that we'll silently ignore unmerged entries */ - if (!strcmp(arg, "--reset")) { - if (stage || merge) - usage(read_tree_usage); - reset = 1; - merge = 1; - stage = 1; - read_cache_unmerged(); - continue; - } - - if (!strcmp(arg, "--trivial")) { - trivial_merges_only = 1; - continue; - } - - if (!strcmp(arg, "--aggressive")) { - aggressive = 1; - continue; - } - - /* "-m" stands for "merge", meaning we start in stage 1 */ - if (!strcmp(arg, "-m")) { - if (stage || merge) - usage(read_tree_usage); - if (read_cache_unmerged()) - die("you need to resolve your current index first"); - stage = 1; - merge = 1; - continue; - } - - /* using -u and -i at the same time makes no sense */ - if (1 < index_only + update) - usage(read_tree_usage); - - if (get_sha1(arg, sha1)) - die("Not a valid object name %s", arg); - if (list_tree(sha1) < 0) - die("failed to unpack tree object %s", arg); - stage++; - } - if ((update||index_only) && !merge) - usage(read_tree_usage); - - if (merge) { - if (stage < 2) - die("just how do you expect me to merge %d trees?", stage-1); - switch (stage - 1) { - case 1: - fn = oneway_merge; - break; - case 2: - fn = twoway_merge; - break; - case 3: - fn = threeway_merge; - break; - default: - fn = threeway_merge; - break; - } - - if (stage - 1 >= 3) - head_idx = stage - 2; - else - head_idx = 1; - } - - unpack_trees(fn); - if (write_cache(newfd, active_cache, active_nr) || - commit_index_file(&cache_file)) - die("unable to write new index file"); - return 0; -}