diff options
Diffstat (limited to 'merge-recursive.c')
| -rw-r--r-- | merge-recursive.c | 1453 |
1 files changed, 1453 insertions, 0 deletions
diff --git a/merge-recursive.c b/merge-recursive.c new file mode 100644 index 0000000000..595b0226ac --- /dev/null +++ b/merge-recursive.c @@ -0,0 +1,1453 @@ +/* + * Recursive Merge algorithm stolen from git-merge-recursive.py by + * Fredrik Kuivinen. + * The thieves were Alex Riesen and Johannes Schindelin, in June/July 2006 + */ +#include "cache.h" +#include "cache-tree.h" +#include "commit.h" +#include "blob.h" +#include "tree-walk.h" +#include "diff.h" +#include "diffcore.h" +#include "run-command.h" +#include "tag.h" +#include "unpack-trees.h" +#include "path-list.h" +#include "xdiff-interface.h" + +static int subtree_merge; + +static struct tree *shift_tree_object(struct tree *one, struct tree *two) +{ + unsigned char shifted[20]; + + /* + * NEEDSWORK: this limits the recursion depth to hardcoded + * value '2' to avoid excessive overhead. + */ + shift_tree(one->object.sha1, two->object.sha1, shifted, 2); + if (!hashcmp(two->object.sha1, shifted)) + return two; + return lookup_tree(shifted); +} + +/* + * A virtual commit has + * - (const char *)commit->util set to the name, and + * - *(int *)commit->object.sha1 set to the virtual id. + */ + +static unsigned commit_list_count(const struct commit_list *l) +{ + unsigned c = 0; + for (; l; l = l->next ) + c++; + return c; +} + +static struct commit *make_virtual_commit(struct tree *tree, const char *comment) +{ + struct commit *commit = xcalloc(1, sizeof(struct commit)); + static unsigned virtual_id = 1; + commit->tree = tree; + commit->util = (void*)comment; + *(int*)commit->object.sha1 = virtual_id++; + /* avoid warnings */ + commit->object.parsed = 1; + return commit; +} + +/* + * Since we use get_tree_entry(), which does not put the read object into + * the object pool, we cannot rely on a == b. + */ +static int sha_eq(const unsigned char *a, const unsigned char *b) +{ + if (!a && !b) + return 2; + return a && b && hashcmp(a, b) == 0; +} + +/* + * Since we want to write the index eventually, we cannot reuse the index + * for these (temporary) data. + */ +struct stage_data +{ + struct + { + unsigned mode; + unsigned char sha[20]; + } stages[4]; + unsigned processed:1; +}; + +struct output_buffer +{ + struct output_buffer *next; + char *str; +}; + +static struct path_list current_file_set = {NULL, 0, 0, 1}; +static struct path_list current_directory_set = {NULL, 0, 0, 1}; + +static int call_depth = 0; +static int verbosity = 2; +static int buffer_output = 1; +static int do_progress = 1; +static unsigned last_percent; +static unsigned merged_cnt; +static unsigned total_cnt; +static volatile sig_atomic_t progress_update; +static struct output_buffer *output_list, *output_end; + +static int show (int v) +{ + return (!call_depth && verbosity >= v) || verbosity >= 5; +} + +static void output(int v, const char *fmt, ...) +{ + va_list args; + va_start(args, fmt); + if (buffer_output && show(v)) { + struct output_buffer *b = xmalloc(sizeof(*b)); + nfvasprintf(&b->str, fmt, args); + b->next = NULL; + if (output_end) + output_end->next = b; + else + output_list = b; + output_end = b; + } else if (show(v)) { + int i; + for (i = call_depth; i--;) + fputs(" ", stdout); + vfprintf(stdout, fmt, args); + fputc('\n', stdout); + } + va_end(args); +} + +static void flush_output() +{ + struct output_buffer *b, *n; + for (b = output_list; b; b = n) { + int i; + for (i = call_depth; i--;) + fputs(" ", stdout); + fputs(b->str, stdout); + fputc('\n', stdout); + n = b->next; + free(b->str); + free(b); + } + output_list = NULL; + output_end = NULL; +} + +static void output_commit_title(struct commit *commit) +{ + int i; + flush_output(); + for (i = call_depth; i--;) + fputs(" ", stdout); + if (commit->util) + printf("virtual %s\n", (char *)commit->util); + else { + printf("%s ", find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV)); + if (parse_commit(commit) != 0) + printf("(bad commit)\n"); + else { + const char *s; + int len; + for (s = commit->buffer; *s; s++) + if (*s == '\n' && s[1] == '\n') { + s += 2; + break; + } + for (len = 0; s[len] && '\n' != s[len]; len++) + ; /* do nothing */ + printf("%.*s\n", len, s); + } + } +} + +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 display_progress() +{ + unsigned percent = total_cnt ? merged_cnt * 100 / total_cnt : 0; + if (progress_update || percent != last_percent) { + fprintf(stderr, "%4u%% (%u/%u) done\r", + percent, merged_cnt, total_cnt); + progress_update = 0; + last_percent = percent; + } +} + +static struct cache_entry *make_cache_entry(unsigned int mode, + const unsigned char *sha1, const char *path, int stage, int refresh) +{ + int size, len; + struct cache_entry *ce; + + if (!verify_path(path)) + return NULL; + + len = strlen(path); + size = cache_entry_size(len); + ce = xcalloc(1, size); + + hashcpy(ce->sha1, sha1); + memcpy(ce->name, path, len); + ce->ce_flags = create_ce_flags(len, stage); + ce->ce_mode = create_ce_mode(mode); + + if (refresh) + return refresh_cache_entry(ce, 0); + + return ce; +} + +static int add_cacheinfo(unsigned int mode, const unsigned char *sha1, + const char *path, int stage, int refresh, int options) +{ + struct cache_entry *ce; + ce = make_cache_entry(mode, sha1 ? sha1 : null_sha1, path, stage, refresh); + if (!ce) + return error("addinfo_cache failed for path '%s'", path); + return add_cache_entry(ce, options); +} + +/* + * This is a global variable which is used in a number of places but + * only written to in the 'merge' function. + * + * index_only == 1 => Don't leave any non-stage 0 entries in the cache and + * don't update the working directory. + * 0 => Leave unmerged entries in the cache and update + * the working directory. + */ +static int index_only = 0; + +static int git_merge_trees(int index_only, + struct tree *common, + struct tree *head, + struct tree *merge) +{ + int rc; + struct object_list *trees = NULL; + struct unpack_trees_options opts; + + memset(&opts, 0, sizeof(opts)); + if (index_only) + opts.index_only = 1; + else + opts.update = 1; + opts.merge = 1; + opts.head_idx = 2; + opts.fn = threeway_merge; + + object_list_append(&common->object, &trees); + object_list_append(&head->object, &trees); + object_list_append(&merge->object, &trees); + + rc = unpack_trees(trees, &opts); + cache_tree_free(&active_cache_tree); + return rc; +} + +static int unmerged_index(void) +{ + int i; + for (i = 0; i < active_nr; i++) { + struct cache_entry *ce = active_cache[i]; + if (ce_stage(ce)) + return 1; + } + return 0; +} + +static struct tree *git_write_tree(void) +{ + struct tree *result = NULL; + + if (unmerged_index()) { + int i; + output(0, "There are unmerged index entries:"); + for (i = 0; i < active_nr; i++) { + struct cache_entry *ce = active_cache[i]; + if (ce_stage(ce)) + output(0, "%d %.*s", ce_stage(ce), ce_namelen(ce), ce->name); + } + return NULL; + } + + if (!active_cache_tree) + active_cache_tree = cache_tree(); + + if (!cache_tree_fully_valid(active_cache_tree) && + cache_tree_update(active_cache_tree, + active_cache, active_nr, 0, 0) < 0) + die("error building trees"); + + result = lookup_tree(active_cache_tree->sha1); + + return result; +} + +static int save_files_dirs(const unsigned char *sha1, + const char *base, int baselen, const char *path, + unsigned int mode, int stage) +{ + int len = strlen(path); + char *newpath = xmalloc(baselen + len + 1); + memcpy(newpath, base, baselen); + memcpy(newpath + baselen, path, len); + newpath[baselen + len] = '\0'; + + if (S_ISDIR(mode)) + path_list_insert(newpath, ¤t_directory_set); + else + path_list_insert(newpath, ¤t_file_set); + free(newpath); + + return READ_TREE_RECURSIVE; +} + +static int get_files_dirs(struct tree *tree) +{ + int n; + if (read_tree_recursive(tree, "", 0, 0, NULL, save_files_dirs) != 0) + return 0; + n = current_file_set.nr + current_directory_set.nr; + return n; +} + +/* + * Returns a index_entry instance which doesn't have to correspond to + * a real cache entry in Git's index. + */ +static struct stage_data *insert_stage_data(const char *path, + struct tree *o, struct tree *a, struct tree *b, + struct path_list *entries) +{ + struct path_list_item *item; + struct stage_data *e = xcalloc(1, sizeof(struct stage_data)); + get_tree_entry(o->object.sha1, path, + e->stages[1].sha, &e->stages[1].mode); + get_tree_entry(a->object.sha1, path, + e->stages[2].sha, &e->stages[2].mode); + get_tree_entry(b->object.sha1, path, + e->stages[3].sha, &e->stages[3].mode); + item = path_list_insert(path, entries); + item->util = e; + return e; +} + +/* + * Create a dictionary mapping file names to stage_data objects. The + * dictionary contains one entry for every path with a non-zero stage entry. + */ +static struct path_list *get_unmerged(void) +{ + struct path_list *unmerged = xcalloc(1, sizeof(struct path_list)); + int i; + + unmerged->strdup_paths = 1; + total_cnt += active_nr; + + for (i = 0; i < active_nr; i++, merged_cnt++) { + struct path_list_item *item; + struct stage_data *e; + struct cache_entry *ce = active_cache[i]; + if (do_progress) + display_progress(); + if (!ce_stage(ce)) + continue; + + item = path_list_lookup(ce->name, unmerged); + if (!item) { + item = path_list_insert(ce->name, unmerged); + item->util = xcalloc(1, sizeof(struct stage_data)); + } + e = item->util; + e->stages[ce_stage(ce)].mode = ntohl(ce->ce_mode); + hashcpy(e->stages[ce_stage(ce)].sha, ce->sha1); + } + + return unmerged; +} + +struct rename +{ + struct diff_filepair *pair; + struct stage_data *src_entry; + struct stage_data *dst_entry; + unsigned processed:1; +}; + +/* + * Get information of all renames which occurred between 'o_tree' and + * 'tree'. We need the three trees in the merge ('o_tree', 'a_tree' and + * 'b_tree') to be able to associate the correct cache entries with + * the rename information. 'tree' is always equal to either a_tree or b_tree. + */ +static struct path_list *get_renames(struct tree *tree, + struct tree *o_tree, + struct tree *a_tree, + struct tree *b_tree, + struct path_list *entries) +{ + int i; + struct path_list *renames; + struct diff_options opts; + + renames = xcalloc(1, sizeof(struct path_list)); + diff_setup(&opts); + opts.recursive = 1; + opts.detect_rename = DIFF_DETECT_RENAME; + opts.output_format = DIFF_FORMAT_NO_OUTPUT; + if (diff_setup_done(&opts) < 0) + die("diff setup failed"); + diff_tree_sha1(o_tree->object.sha1, tree->object.sha1, "", &opts); + diffcore_std(&opts); + for (i = 0; i < diff_queued_diff.nr; ++i) { + struct path_list_item *item; + struct rename *re; + struct diff_filepair *pair = diff_queued_diff.queue[i]; + if (pair->status != 'R') { + diff_free_filepair(pair); + continue; + } + re = xmalloc(sizeof(*re)); + re->processed = 0; + re->pair = pair; + item = path_list_lookup(re->pair->one->path, entries); + if (!item) + re->src_entry = insert_stage_data(re->pair->one->path, + o_tree, a_tree, b_tree, entries); + else + re->src_entry = item->util; + + item = path_list_lookup(re->pair->two->path, entries); + if (!item) + re->dst_entry = insert_stage_data(re->pair->two->path, + o_tree, a_tree, b_tree, entries); + else + re->dst_entry = item->util; + item = path_list_insert(pair->one->path, renames); + item->util = re; + } + opts.output_format = DIFF_FORMAT_NO_OUTPUT; + diff_queued_diff.nr = 0; + diff_flush(&opts); + return renames; +} + +static int update_stages(const char *path, struct diff_filespec *o, + struct diff_filespec *a, struct diff_filespec *b, + int clear) +{ + int options = ADD_CACHE_OK_TO_ADD | ADD_CACHE_OK_TO_REPLACE; + if (clear) + if (remove_file_from_cache(path)) + return -1; + if (o) + if (add_cacheinfo(o->mode, o->sha1, path, 1, 0, options)) + return -1; + if (a) + if (add_cacheinfo(a->mode, a->sha1, path, 2, 0, options)) + return -1; + if (b) + if (add_cacheinfo(b->mode, b->sha1, path, 3, 0, options)) + return -1; + return 0; +} + +static int remove_path(const char *name) +{ + int ret, len; + char *slash, *dirs; + + ret = unlink(name); + if (ret) + return ret; + len = strlen(name); + dirs = xmalloc(len+1); + memcpy(dirs, name, len); + dirs[len] = '\0'; + while ((slash = strrchr(name, '/'))) { + *slash = '\0'; + len = slash - name; + if (rmdir(name) != 0) + break; + } + free(dirs); + return ret; +} + +static int remove_file(int clean, const char *path, int no_wd) +{ + int update_cache = index_only || clean; + int update_working_directory = !index_only && !no_wd; + + if (update_cache) { + if (remove_file_from_cache(path)) + return -1; + } + if (update_working_directory) { + unlink(path); + if (errno != ENOENT || errno != EISDIR) + return -1; + remove_path(path); + } + return 0; +} + +static char *unique_path(const char *path, const char *branch) +{ + char *newpath = xmalloc(strlen(path) + 1 + strlen(branch) + 8 + 1); + int suffix = 0; + struct stat st; + char *p = newpath + strlen(path); + strcpy(newpath, path); + *(p++) = '~'; + strcpy(p, branch); + for (; *p; ++p) + if ('/' == *p) + *p = '_'; + while (path_list_has_path(¤t_file_set, newpath) || + path_list_has_path(¤t_directory_set, newpath) || + lstat(newpath, &st) == 0) + sprintf(p, "_%d", suffix++); + + path_list_insert(newpath, ¤t_file_set); + return newpath; +} + +static int mkdir_p(const char *path, unsigned long mode) +{ + /* path points to cache entries, so xstrdup before messing with it */ + char *buf = xstrdup(path); + int result = safe_create_leading_directories(buf); + free(buf); + return result; +} + +static void flush_buffer(int fd, const char *buf, unsigned long size) +{ + while (size > 0) { + long ret = write_in_full(fd, buf, size); + if (ret < 0) { + /* Ignore epipe */ + if (errno == EPIPE) + break; + die("merge-recursive: %s", strerror(errno)); + } else if (!ret) { + die("merge-recursive: disk full?"); + } + size -= ret; + buf += ret; + } +} + +static void update_file_flags(const unsigned char *sha, + unsigned mode, + const char *path, + int update_cache, + int update_wd) +{ + if (index_only) + update_wd = 0; + + if (update_wd) { + enum object_type type; + void *buf; + unsigned long size; + + buf = read_sha1_file(sha, &type, &size); + if (!buf) + die("cannot read object %s '%s'", sha1_to_hex(sha), path); + if (type != OBJ_BLOB) + die("blob expected for %s '%s'", sha1_to_hex(sha), path); + + if (S_ISREG(mode) || (!has_symlinks && S_ISLNK(mode))) { + int fd; + int status; + const char *msg = "failed to create path '%s'%s"; + + status = mkdir_p(path, 0777); + if (status) { + if (status == -3) { + /* something else exists */ + error(msg, path, ": perhaps a D/F conflict?"); + update_wd = 0; + goto update_index; + } + die(msg, path, ""); + } + if (unlink(path)) { + if (errno == EISDIR) { + /* something else exists */ + error(msg, path, ": perhaps a D/F conflict?"); + update_wd = 0; + goto update_index; + } + if (errno != ENOENT) + die("failed to unlink %s " + "in preparation to update: %s", + path, strerror(errno)); + } + if (mode & 0100) + mode = 0777; + else + mode = 0666; + fd = open(path, O_WRONLY | O_TRUNC | O_CREAT, mode); + if (fd < 0) + die("failed to open %s: %s", path, strerror(errno)); + flush_buffer(fd, buf, size); + close(fd); + } else if (S_ISLNK(mode)) { + char *lnk = xmalloc(size + 1); + memcpy(lnk, buf, size); + lnk[size] = '\0'; + mkdir_p(path, 0777); + unlink(path); + symlink(lnk, path); + free(lnk); + } else + die("do not know what to do with %06o %s '%s'", + mode, sha1_to_hex(sha), path); + } + update_index: + if (update_cache) + add_cacheinfo(mode, sha, path, 0, update_wd, ADD_CACHE_OK_TO_ADD); +} + +static void update_file(int clean, + const unsigned char *sha, + unsigned mode, + const char *path) +{ + update_file_flags(sha, mode, path, index_only || clean, !index_only); +} + +/* Low level file merging, update and removal */ + +struct merge_file_info +{ + unsigned char sha[20]; + unsigned mode; + unsigned clean:1, + merge:1; +}; + +static void fill_mm(const unsigned char *sha1, mmfile_t *mm) +{ + unsigned long size; + enum object_type type; + + if (!hashcmp(sha1, null_sha1)) { + mm->ptr = xstrdup(""); + mm->size = 0; + return; + } + + mm->ptr = read_sha1_file(sha1, &type, &size); + if (!mm->ptr || type != OBJ_BLOB) + die("unable to read blob object %s", sha1_to_hex(sha1)); + mm->size = size; +} + +static struct merge_file_info merge_file(struct diff_filespec *o, + struct diff_filespec *a, struct diff_filespec *b, + const char *branch1, const char *branch2) +{ + struct merge_file_info result; + result.merge = 0; + result.clean = 1; + + if ((S_IFMT & a->mode) != (S_IFMT & b->mode)) { + result.clean = 0; + if (S_ISREG(a->mode)) { + result.mode = a->mode; + hashcpy(result.sha, a->sha1); + } else { + result.mode = b->mode; + hashcpy(result.sha, b->sha1); + } + } else { + if (!sha_eq(a->sha1, o->sha1) && !sha_eq(b->sha1, o->sha1)) + result.merge = 1; + + result.mode = a->mode == o->mode ? b->mode: a->mode; + + if (sha_eq(a->sha1, o->sha1)) + hashcpy(result.sha, b->sha1); + else if (sha_eq(b->sha1, o->sha1)) + hashcpy(result.sha, a->sha1); + else if (S_ISREG(a->mode)) { + mmfile_t orig, src1, src2; + mmbuffer_t result_buf; + xpparam_t xpp; + char *name1, *name2; + int merge_status; + + name1 = xstrdup(mkpath("%s:%s", branch1, a->path)); + name2 = xstrdup(mkpath("%s:%s", branch2, b->path)); + + fill_mm(o->sha1, &orig); + fill_mm(a->sha1, &src1); + fill_mm(b->sha1, &src2); + + memset(&xpp, 0, sizeof(xpp)); + merge_status = xdl_merge(&orig, + &src1, name1, + &src2, name2, + &xpp, XDL_MERGE_ZEALOUS, + &result_buf); + free(name1); + free(name2); + free(orig.ptr); + free(src1.ptr); + free(src2.ptr); + + if ((merge_status < 0) || !result_buf.ptr) + die("Failed to execute internal merge"); + + if (write_sha1_file(result_buf.ptr, result_buf.size, + blob_type, result.sha)) + die("Unable to add %s to database", + a->path); + + free(result_buf.ptr); + result.clean = (merge_status == 0); + } else { + if (!(S_ISLNK(a->mode) || S_ISLNK(b->mode))) + die("cannot merge modes?"); + + hashcpy(result.sha, a->sha1); + + if (!sha_eq(a->sha1, b->sha1)) + result.clean = 0; + } + } + + return result; +} + +static void conflict_rename_rename(struct rename *ren1, + const char *branch1, + struct rename *ren2, + const char *branch2) +{ + char *del[2]; + int delp = 0; + const char *ren1_dst = ren1->pair->two->path; + const char *ren2_dst = ren2->pair->two->path; + const char *dst_name1 = ren1_dst; + const char *dst_name2 = ren2_dst; + if (path_list_has_path(¤t_directory_set, ren1_dst)) { + dst_name1 = del[delp++] = unique_path(ren1_dst, branch1); + output(1, "%s is a directory in %s added as %s instead", + ren1_dst, branch2, dst_name1); + remove_file(0, ren1_dst, 0); + } + if (path_list_has_path(¤t_directory_set, ren2_dst)) { + dst_name2 = del[delp++] = unique_path(ren2_dst, branch2); + output(1, "%s is a directory in %s added as %s instead", + ren2_dst, branch1, dst_name2); + remove_file(0, ren2_dst, 0); + } + if (index_only) { + remove_file_from_cache(dst_name1); + remove_file_from_cache(dst_name2); + /* + * Uncomment to leave the conflicting names in the resulting tree + * + * update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, dst_name1); + * update_file(0, ren2->pair->two->sha1, ren2->pair->two->mode, dst_name2); + */ + } else { + update_stages(dst_name1, NULL, ren1->pair->two, NULL, 1); + update_stages(dst_name2, NULL, NULL, ren2->pair->two, 1); + } + while (delp--) + free(del[delp]); +} + +static void conflict_rename_dir(struct rename *ren1, + const char *branch1) +{ + char *new_path = unique_path(ren1->pair->two->path, branch1); + output(1, "Renamed %s to %s instead", ren1->pair->one->path, new_path); + remove_file(0, ren1->pair->two->path, 0); + update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path); + free(new_path); +} + +static void conflict_rename_rename_2(struct rename *ren1, + const char *branch1, + struct rename *ren2, + const char *branch2) +{ + char *new_path1 = unique_path(ren1->pair->two->path, branch1); + char *new_path2 = unique_path(ren2->pair->two->path, branch2); + output(1, "Renamed %s to %s and %s to %s instead", + ren1->pair->one->path, new_path1, + ren2->pair->one->path, new_path2); + remove_file(0, ren1->pair->two->path, 0); + update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path1); + update_file(0, ren2->pair->two->sha1, ren2->pair->two->mode, new_path2); + free(new_path2); + free(new_path1); +} + +static int process_renames(struct path_list *a_renames, + struct path_list *b_renames, + const char *a_branch, + const char *b_branch) +{ + int clean_merge = 1, i, j; + struct path_list a_by_dst = {NULL, 0, 0, 0}, b_by_dst = {NULL, 0, 0, 0}; + const struct rename *sre; + + for (i = 0; i < a_renames->nr; i++) { + sre = a_renames->items[i].util; + path_list_insert(sre->pair->two->path, &a_by_dst)->util + = sre->dst_entry; + } + for (i = 0; i < b_renames->nr; i++) { + sre = b_renames->items[i].util; + path_list_insert(sre->pair->two->path, &b_by_dst)->util + = sre->dst_entry; + } + + for (i = 0, j = 0; i < a_renames->nr || j < b_renames->nr;) { + int compare; + char *src; + struct path_list *renames1, *renames2, *renames2Dst; + struct rename *ren1 = NULL, *ren2 = NULL; + const char *branch1, *branch2; + const char *ren1_src, *ren1_dst; + + if (i >= a_renames->nr) { + compare = 1; + ren2 = b_renames->items[j++].util; + } else if (j >= b_renames->nr) { + compare = -1; + ren1 = a_renames->items[i++].util; + } else { + compare = strcmp(a_renames->items[i].path, + b_renames->items[j].path); + if (compare <= 0) + ren1 = a_renames->items[i++].util; + if (compare >= 0) + ren2 = b_renames->items[j++].util; + } + + /* TODO: refactor, so that 1/2 are not needed */ + if (ren1) { + renames1 = a_renames; + renames2 = b_renames; + renames2Dst = &b_by_dst; + branch1 = a_branch; + branch2 = b_branch; + } else { + struct rename *tmp; + renames1 = b_renames; + renames2 = a_renames; + renames2Dst = &a_by_dst; + branch1 = b_branch; + branch2 = a_branch; + tmp = ren2; + ren2 = ren1; + ren1 = tmp; + } + src = ren1->pair->one->path; + + ren1->dst_entry->processed = 1; + ren1->src_entry->processed = 1; + + if (ren1->processed) + continue; + ren1->processed = 1; + + ren1_src = ren1->pair->one->path; + ren1_dst = ren1->pair->two->path; + + if (ren2) { + const char *ren2_src = ren2->pair->one->path; + const char *ren2_dst = ren2->pair->two->path; + /* Renamed in 1 and renamed in 2 */ + if (strcmp(ren1_src, ren2_src) != 0) + die("ren1.src != ren2.src"); + ren2->dst_entry->processed = 1; + ren2->processed = 1; + if (strcmp(ren1_dst, ren2_dst) != 0) { + clean_merge = 0; + output(1, "CONFLICT (rename/rename): " + "Rename \"%s\"->\"%s\" in branch \"%s\" " + "rename \"%s\"->\"%s\" in \"%s\"%s", + src, ren1_dst, branch1, + src, ren2_dst, branch2, + index_only ? " (left unresolved)": ""); + if (index_only) { + remove_file_from_cache(src); + update_file(0, ren1->pair->one->sha1, + ren1->pair->one->mode, src); + } + conflict_rename_rename(ren1, branch1, ren2, branch2); + } else { + struct merge_file_info mfi; + remove_file(1, ren1_src, 1); + mfi = merge_file(ren1->pair->one, + ren1->pair->two, + ren2->pair->two, + branch1, + branch2); + if (mfi.merge || !mfi.clean) + output(1, "Renamed %s->%s", src, ren1_dst); + + if (mfi.merge) + output(2, "Auto-merged %s", ren1_dst); + + if (!mfi.clean) { + output(1, "CONFLICT (content): merge conflict in %s", + ren1_dst); + clean_merge = 0; + + if (!index_only) + update_stages(ren1_dst, + ren1->pair->one, + ren1->pair->two, + ren2->pair->two, + 1 /* clear */); + } + update_file(mfi.clean, mfi.sha, mfi.mode, ren1_dst); + } + } else { + /* Renamed in 1, maybe changed in 2 */ + struct path_list_item *item; + /* we only use sha1 and mode of these */ + struct diff_filespec src_other, dst_other; + int try_merge, stage = a_renames == renames1 ? 3: 2; + + remove_file(1, ren1_src, index_only || stage == 3); + + hashcpy(src_other.sha1, ren1->src_entry->stages[stage].sha); + src_other.mode = ren1->src_entry->stages[stage].mode; + hashcpy(dst_other.sha1, ren1->dst_entry->stages[stage].sha); + dst_other.mode = ren1->dst_entry->stages[stage].mode; + + try_merge = 0; + + if (path_list_has_path(¤t_directory_set, ren1_dst)) { + clean_merge = 0; + output(1, "CONFLICT (rename/directory): Renamed %s->%s in %s " + " directory %s added in %s", + ren1_src, ren1_dst, branch1, + ren1_dst, branch2); + conflict_rename_dir(ren1, branch1); + } else if (sha_eq(src_other.sha1, null_sha1)) { + clean_merge = 0; + output(1, "CONFLICT (rename/delete): Renamed %s->%s in %s " + "and deleted in %s", + ren1_src, ren1_dst, branch1, + branch2); + update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, ren1_dst); + } else if (!sha_eq(dst_other.sha1, null_sha1)) { + const char *new_path; + clean_merge = 0; + try_merge = 1; + output(1, "CONFLICT (rename/add): Renamed %s->%s in %s. " + "%s added in %s", + ren1_src, ren1_dst, branch1, + ren1_dst, branch2); + new_path = unique_path(ren1_dst, branch2); + output(1, "Added as %s instead", new_path); + update_file(0, dst_other.sha1, dst_other.mode, new_path); + } else if ((item = path_list_lookup(ren1_dst, renames2Dst))) { + ren2 = item->util; + clean_merge = 0; + ren2->processed = 1; + output(1, "CONFLICT (rename/rename): Renamed %s->%s in %s. " + "Renamed %s->%s in %s", + ren1_src, ren1_dst, branch1, + ren2->pair->one->path, ren2->pair->two->path, branch2); + conflict_rename_rename_2(ren1, branch1, ren2, branch2); + } else + try_merge = 1; + + if (try_merge) { + struct diff_filespec *o, *a, *b; + struct merge_file_info mfi; + src_other.path = (char *)ren1_src; + + o = ren1->pair->one; + if (a_renames == renames1) { + a = ren1->pair->two; + b = &src_other; + } else { + b = ren1->pair->two; + a = &src_other; + } + mfi = merge_file(o, a, b, + a_branch, b_branch); + + if (mfi.merge || !mfi.clean) + output(1, "Renamed %s => %s", ren1_src, ren1_dst); + if (mfi.merge) + output(2, "Auto-merged %s", ren1_dst); + if (!mfi.clean) { + output(1, "CONFLICT (rename/modify): Merge conflict in %s", + ren1_dst); + clean_merge = 0; + + if (!index_only) + update_stages(ren1_dst, + o, a, b, 1); + } + update_file(mfi.clean, mfi.sha, mfi.mode, ren1_dst); + } + } + } + path_list_clear(&a_by_dst, 0); + path_list_clear(&b_by_dst, 0); + + return clean_merge; +} + +static unsigned char *stage_sha(const unsigned char *sha, unsigned mode) +{ + return (is_null_sha1(sha) || mode == 0) ? NULL: (unsigned char *)sha; +} + +/* Per entry merge function */ +static int process_entry(const char *path, struct stage_data *entry, + const char *branch1, + const char *branch2) +{ + /* + printf("processing entry, clean cache: %s\n", index_only ? "yes": "no"); + print_index_entry("\tpath: ", entry); + */ + int clean_merge = 1; + unsigned o_mode = entry->stages[1].mode; + unsigned a_mode = entry->stages[2].mode; + unsigned b_mode = entry->stages[3].mode; + unsigned char *o_sha = stage_sha(entry->stages[1].sha, o_mode); + unsigned char *a_sha = stage_sha(entry->stages[2].sha, a_mode); + unsigned char *b_sha = stage_sha(entry->stages[3].sha, b_mode); + + if (o_sha && (!a_sha || !b_sha)) { + /* Case A: Deleted in one */ + if ((!a_sha && !b_sha) || + (sha_eq(a_sha, o_sha) && !b_sha) || + (!a_sha && sha_eq(b_sha, o_sha))) { + /* Deleted in both or deleted in one and + * unchanged in the other */ + if (a_sha) + output(2, "Removed %s", path); + /* do not touch working file if it did not exist */ + remove_file(1, path, !a_sha); + } else { + /* Deleted in one and changed in the other */ + clean_merge = 0; + if (!a_sha) { + output(1, "CONFLICT (delete/modify): %s deleted in %s " + "and modified in %s. Version %s of %s left in tree.", + path, branch1, + branch2, branch2, path); + update_file(0, b_sha, b_mode, path); + } else { + output(1, "CONFLICT (delete/modify): %s deleted in %s " + "and modified in %s. Version %s of %s left in tree.", + path, branch2, + branch1, branch1, path); + update_file(0, a_sha, a_mode, path); + } + } + + } else if ((!o_sha && a_sha && !b_sha) || + (!o_sha && !a_sha && b_sha)) { + /* Case B: Added in one. */ + const char *add_branch; + const char *other_branch; + unsigned mode; + const unsigned char *sha; + const char *conf; + + if (a_sha) { + add_branch = branch1; + other_branch = branch2; + mode = a_mode; + sha = a_sha; + conf = "file/directory"; + } else { + add_branch = branch2; + other_branch = branch1; + mode = b_mode; + sha = b_sha; + conf = "directory/file"; + } + if (path_list_has_path(¤t_directory_set, path)) { + const char *new_path = unique_path(path, add_branch); + clean_merge = 0; + output(1, "CONFLICT (%s): There is a directory with name %s in %s. " + "Added %s as %s", + conf, path, other_branch, path, new_path); + remove_file(0, path, 0); + update_file(0, sha, mode, new_path); + } else { + output(2, "Added %s", path); + update_file(1, sha, mode, path); + } + } else if (a_sha && b_sha) { + /* Case C: Added in both (check for same permissions) and */ + /* case D: Modified in both, but differently. */ + const char *reason = "content"; + struct merge_file_info mfi; + struct diff_filespec o, a, b; + + if (!o_sha) { + reason = "add/add"; + o_sha = (unsigned char *)null_sha1; + } + output(2, "Auto-merged %s", path); + o.path = a.path = b.path = (char *)path; + hashcpy(o.sha1, o_sha); + o.mode = o_mode; + hashcpy(a.sha1, a_sha); + a.mode = a_mode; + hashcpy(b.sha1, b_sha); + b.mode = b_mode; + + mfi = merge_file(&o, &a, &b, + branch1, branch2); + + if (mfi.clean) + update_file(1, mfi.sha, mfi.mode, path); + else { + clean_merge = 0; + output(1, "CONFLICT (%s): Merge conflict in %s", + reason, path); + + if (index_only) + update_file(0, mfi.sha, mfi.mode, path); + else + update_file_flags(mfi.sha, mfi.mode, path, + 0 /* update_cache */, 1 /* update_working_directory */); + } + } else if (!o_sha && !a_sha && !b_sha) { + /* + * this entry was deleted altogether. a_mode == 0 means + * we had that path and want to actively remove it. + */ + remove_file(1, path, !a_mode); + } else + die("Fatal merge failure, shouldn't happen."); + + return clean_merge; +} + +static int merge_trees(struct tree *head, + struct tree *merge, + struct tree *common, + const char *branch1, + const char *branch2, + struct tree **result) +{ + int code, clean; + + if (subtree_merge) { + merge = shift_tree_object(head, merge); + common = shift_tree_object(head, common); + } + + if (sha_eq(common->object.sha1, merge->object.sha1)) { + output(0, "Already uptodate!"); + *result = head; + return 1; + } + + code = git_merge_trees(index_only, common, head, merge); + + if (code != 0) + die("merging of trees %s and %s failed", + sha1_to_hex(head->object.sha1), + sha1_to_hex(merge->object.sha1)); + + if (unmerged_index()) { + struct path_list *entries, *re_head, *re_merge; + int i; + path_list_clear(¤t_file_set, 1); + path_list_clear(¤t_directory_set, 1); + get_files_dirs(head); + get_files_dirs(merge); + + entries = get_unmerged(); + re_head = get_renames(head, common, head, merge, entries); + re_merge = get_renames(merge, common, head, merge, entries); + clean = process_renames(re_head, re_merge, + branch1, branch2); + total_cnt += entries->nr; + for (i = 0; i < entries->nr; i++, merged_cnt++) { + const char *path = entries->items[i].path; + struct stage_data *e = entries->items[i].util; + if (!e->processed + && !process_entry(path, e, branch1, branch2)) + clean = 0; + if (do_progress) + display_progress(); + } + + path_list_clear(re_merge, 0); + path_list_clear(re_head, 0); + path_list_clear(entries, 1); + + } + else + clean = 1; + + if (index_only) + *result = git_write_tree(); + + return clean; +} + +static struct commit_list *reverse_commit_list(struct commit_list *list) +{ + struct commit_list *next = NULL, *current, *backup; + for (current = list; current; current = backup) { + backup = current->next; + current->next = next; + next = current; + } + return next; +} + +/* + * Merge the commits h1 and h2, return the resulting virtual + * commit object and a flag indicating the cleanness of the merge. + */ +static int merge(struct commit *h1, + struct commit *h2, + const char *branch1, + const char *branch2, + struct commit_list *ca, + struct commit **result) +{ + struct commit_list *iter; + struct commit *merged_common_ancestors; + struct tree *mrtree; + int clean; + + if (show(4)) { + output(4, "Merging:"); + output_commit_title(h1); + output_commit_title(h2); + } + + if (!ca) { + ca = get_merge_bases(h1, h2, 1); + ca = reverse_commit_list(ca); + } + + if (show(5)) { + output(5, "found %u common ancestor(s):", commit_list_count(ca)); + for (iter = ca; iter; iter = iter->next) + output_commit_title(iter->item); + } + + merged_common_ancestors = pop_commit(&ca); + if (merged_common_ancestors == NULL) { + /* if there is no common ancestor, make an empty tree */ + 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); + merged_common_ancestors = make_virtual_commit(tree, "ancestor"); + } + + for (iter = ca; iter; iter = iter->next) { + call_depth++; + /* + * When the merge fails, the result contains files + * with conflict markers. The cleanness flag is + * ignored, it was never actually used, as result of + * merge_trees has always overwritten it: the committed + * "conflicts" were already resolved. + */ + discard_cache(); + merge(merged_common_ancestors, iter->item, + "Temporary merge branch 1", + "Temporary merge branch 2", + NULL, + &merged_common_ancestors); + call_depth--; + + if (!merged_common_ancestors) + die("merge returned no commit"); + } + + discard_cache(); + if (!call_depth) { + read_cache(); + index_only = 0; + } else + index_only = 1; + + clean = merge_trees(h1->tree, h2->tree, merged_common_ancestors->tree, + branch1, branch2, &mrtree); + + if (index_only) { + *result = make_virtual_commit(mrtree, "merged tree"); + commit_list_insert(h1, &(*result)->parents); + commit_list_insert(h2, &(*result)->parents->next); + } + if (!call_depth && do_progress) { + /* Make sure we end at 100% */ + if (!total_cnt) + total_cnt = 1; + merged_cnt = total_cnt; + progress_update = 1; + display_progress(); + fputc('\n', stderr); + } + flush_output(); + return clean; +} + +static const char *better_branch_name(const char *branch) +{ + static char githead_env[8 + 40 + 1]; + char *name; + + if (strlen(branch) != 40) + return branch; + sprintf(githead_env, "GITHEAD_%s", branch); + name = getenv(githead_env); + return name ? name : branch; +} + +static struct commit *get_ref(const char *ref) +{ + unsigned char sha1[20]; + struct object *object; + + if (get_sha1(ref, sha1)) + die("Could not resolve ref '%s'", ref); + object = deref_tag(parse_object(sha1), ref, strlen(ref)); + if (object->type == OBJ_TREE) + return make_virtual_commit((struct tree*)object, + better_branch_name(ref)); + if (object->type != OBJ_COMMIT) + return NULL; + if (parse_commit((struct commit *)object)) + die("Could not parse commit '%s'", sha1_to_hex(object->sha1)); + return (struct commit *)object; +} + +static int merge_config(const char *var, const char *value) +{ + if (!strcasecmp(var, "merge.verbosity")) { + verbosity = git_config_int(var, value); + return 0; + } + return git_default_config(var, value); +} + +int main(int argc, char *argv[]) +{ + static const char *bases[20]; + static unsigned bases_count = 0; + int i, clean; + const char *branch1, *branch2; + struct commit *result, *h1, *h2; + struct commit_list *ca = NULL; + struct lock_file *lock = xcalloc(1, sizeof(struct lock_file)); + int index_fd; + + if (argv[0]) { + int namelen = strlen(argv[0]); + if (8 < namelen && + !strcmp(argv[0] + namelen - 8, "-subtree")) + subtree_merge = 1; + } + + git_config(merge_config); + if (getenv("GIT_MERGE_VERBOSITY")) + verbosity = strtol(getenv("GIT_MERGE_VERBOSITY"), NULL, 10); + + if (argc < 4) + die("Usage: %s <base>... -- <head> <remote> ...\n", argv[0]); + + for (i = 1; i < argc; ++i) { + if (!strcmp(argv[i], "--")) + break; + if (bases_count < sizeof(bases)/sizeof(*bases)) + bases[bases_count++] = argv[i]; + } + if (argc - i != 3) /* "--" "<head>" "<remote>" */ + die("Not handling anything other than two heads merge."); + if (verbosity >= 5) { + buffer_output = 0; + do_progress = 0; + } + else + do_progress = isatty(1); + + branch1 = argv[++i]; + branch2 = argv[++i]; + + h1 = get_ref(branch1); + h2 = get_ref(branch2); + + branch1 = better_branch_name(branch1); + branch2 = better_branch_name(branch2); + + if (do_progress) + setup_progress_signal(); + if (show(3)) + printf("Merging %s with %s\n", branch1, branch2); + + index_fd = hold_locked_index(lock, 1); + + for (i = 0; i < bases_count; i++) { + struct commit *ancestor = get_ref(bases[i]); + ca = commit_list_insert(ancestor, &ca); + } + clean = merge(h1, h2, branch1, branch2, ca, &result); + + if (active_cache_changed && + (write_cache(index_fd, active_cache, active_nr) || + close(index_fd) || commit_locked_index(lock))) + die ("unable to write %s", get_index_file()); + + return clean ? 0: 1; +} |