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Diffstat (limited to 'merge-recursive.c')
| -rw-r--r-- | merge-recursive.c | 2273 |
1 files changed, 2273 insertions, 0 deletions
diff --git a/merge-recursive.c b/merge-recursive.c new file mode 100644 index 0000000000..1d3f8f0d22 --- /dev/null +++ b/merge-recursive.c @@ -0,0 +1,2273 @@ +/* + * 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 "config.h" +#include "advice.h" +#include "lockfile.h" +#include "cache-tree.h" +#include "commit.h" +#include "blob.h" +#include "builtin.h" +#include "tree-walk.h" +#include "diff.h" +#include "diffcore.h" +#include "tag.h" +#include "unpack-trees.h" +#include "string-list.h" +#include "xdiff-interface.h" +#include "ll-merge.h" +#include "attr.h" +#include "merge-recursive.h" +#include "dir.h" +#include "submodule.h" + +struct path_hashmap_entry { + struct hashmap_entry e; + char path[FLEX_ARRAY]; +}; + +static int path_hashmap_cmp(const void *cmp_data, + const void *entry, + const void *entry_or_key, + const void *keydata) +{ + const struct path_hashmap_entry *a = entry; + const struct path_hashmap_entry *b = entry_or_key; + const char *key = keydata; + + if (ignore_case) + return strcasecmp(a->path, key ? key : b->path); + else + return strcmp(a->path, key ? key : b->path); +} + +static unsigned int path_hash(const char *path) +{ + return ignore_case ? strihash(path) : strhash(path); +} + +static void flush_output(struct merge_options *o) +{ + if (o->buffer_output < 2 && o->obuf.len) { + fputs(o->obuf.buf, stdout); + strbuf_reset(&o->obuf); + } +} + +static int err(struct merge_options *o, const char *err, ...) +{ + va_list params; + + if (o->buffer_output < 2) + flush_output(o); + else { + strbuf_complete(&o->obuf, '\n'); + strbuf_addstr(&o->obuf, "error: "); + } + va_start(params, err); + strbuf_vaddf(&o->obuf, err, params); + va_end(params); + if (o->buffer_output > 1) + strbuf_addch(&o->obuf, '\n'); + else { + error("%s", o->obuf.buf); + strbuf_reset(&o->obuf); + } + + return -1; +} + +static struct tree *shift_tree_object(struct tree *one, struct tree *two, + const char *subtree_shift) +{ + struct object_id shifted; + + if (!*subtree_shift) { + shift_tree(&one->object.oid, &two->object.oid, &shifted, 0); + } else { + shift_tree_by(&one->object.oid, &two->object.oid, &shifted, + subtree_shift); + } + if (!oidcmp(&two->object.oid, &shifted)) + return two; + return lookup_tree(&shifted); +} + +static struct commit *make_virtual_commit(struct tree *tree, const char *comment) +{ + struct commit *commit = alloc_commit_node(); + + set_merge_remote_desc(commit, comment, (struct object *)commit); + commit->tree = tree; + 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 oid_eq(const struct object_id *a, const struct object_id *b) +{ + if (!a && !b) + return 2; + return a && b && oidcmp(a, b) == 0; +} + +enum rename_type { + RENAME_NORMAL = 0, + RENAME_DELETE, + RENAME_ONE_FILE_TO_ONE, + RENAME_ONE_FILE_TO_TWO, + RENAME_TWO_FILES_TO_ONE +}; + +struct rename_conflict_info { + enum rename_type rename_type; + struct diff_filepair *pair1; + struct diff_filepair *pair2; + const char *branch1; + const char *branch2; + struct stage_data *dst_entry1; + struct stage_data *dst_entry2; + struct diff_filespec ren1_other; + struct diff_filespec ren2_other; +}; + +/* + * Since we want to write the index eventually, we cannot reuse the index + * for these (temporary) data. + */ +struct stage_data { + struct { + unsigned mode; + struct object_id oid; + } stages[4]; + struct rename_conflict_info *rename_conflict_info; + unsigned processed:1; +}; + +static inline void setup_rename_conflict_info(enum rename_type rename_type, + struct diff_filepair *pair1, + struct diff_filepair *pair2, + const char *branch1, + const char *branch2, + struct stage_data *dst_entry1, + struct stage_data *dst_entry2, + struct merge_options *o, + struct stage_data *src_entry1, + struct stage_data *src_entry2) +{ + struct rename_conflict_info *ci = xcalloc(1, sizeof(struct rename_conflict_info)); + ci->rename_type = rename_type; + ci->pair1 = pair1; + ci->branch1 = branch1; + ci->branch2 = branch2; + + ci->dst_entry1 = dst_entry1; + dst_entry1->rename_conflict_info = ci; + dst_entry1->processed = 0; + + assert(!pair2 == !dst_entry2); + if (dst_entry2) { + ci->dst_entry2 = dst_entry2; + ci->pair2 = pair2; + dst_entry2->rename_conflict_info = ci; + } + + if (rename_type == RENAME_TWO_FILES_TO_ONE) { + /* + * For each rename, there could have been + * modifications on the side of history where that + * file was not renamed. + */ + int ostage1 = o->branch1 == branch1 ? 3 : 2; + int ostage2 = ostage1 ^ 1; + + ci->ren1_other.path = pair1->one->path; + oidcpy(&ci->ren1_other.oid, &src_entry1->stages[ostage1].oid); + ci->ren1_other.mode = src_entry1->stages[ostage1].mode; + + ci->ren2_other.path = pair2->one->path; + oidcpy(&ci->ren2_other.oid, &src_entry2->stages[ostage2].oid); + ci->ren2_other.mode = src_entry2->stages[ostage2].mode; + } +} + +static int show(struct merge_options *o, int v) +{ + return (!o->call_depth && o->verbosity >= v) || o->verbosity >= 5; +} + +__attribute__((format (printf, 3, 4))) +static void output(struct merge_options *o, int v, const char *fmt, ...) +{ + va_list ap; + + if (!show(o, v)) + return; + + strbuf_addchars(&o->obuf, ' ', o->call_depth * 2); + + va_start(ap, fmt); + strbuf_vaddf(&o->obuf, fmt, ap); + va_end(ap); + + strbuf_addch(&o->obuf, '\n'); + if (!o->buffer_output) + flush_output(o); +} + +static void output_commit_title(struct merge_options *o, struct commit *commit) +{ + strbuf_addchars(&o->obuf, ' ', o->call_depth * 2); + if (commit->util) + strbuf_addf(&o->obuf, "virtual %s\n", + merge_remote_util(commit)->name); + else { + strbuf_add_unique_abbrev(&o->obuf, commit->object.oid.hash, + DEFAULT_ABBREV); + strbuf_addch(&o->obuf, ' '); + if (parse_commit(commit) != 0) + strbuf_addstr(&o->obuf, _("(bad commit)\n")); + else { + const char *title; + const char *msg = get_commit_buffer(commit, NULL); + int len = find_commit_subject(msg, &title); + if (len) + strbuf_addf(&o->obuf, "%.*s\n", len, title); + unuse_commit_buffer(commit, msg); + } + } + flush_output(o); +} + +static int add_cacheinfo(struct merge_options *o, + unsigned int mode, const struct object_id *oid, + const char *path, int stage, int refresh, int options) +{ + struct cache_entry *ce; + int ret; + + ce = make_cache_entry(mode, oid ? oid->hash : null_sha1, path, stage, 0); + if (!ce) + return err(o, _("addinfo_cache failed for path '%s'"), path); + + ret = add_cache_entry(ce, options); + if (refresh) { + struct cache_entry *nce; + + nce = refresh_cache_entry(ce, CE_MATCH_REFRESH | CE_MATCH_IGNORE_MISSING); + if (!nce) + return err(o, _("addinfo_cache failed for path '%s'"), path); + if (nce != ce) + ret = add_cache_entry(nce, options); + } + return ret; +} + +static void init_tree_desc_from_tree(struct tree_desc *desc, struct tree *tree) +{ + parse_tree(tree); + init_tree_desc(desc, tree->buffer, tree->size); +} + +static int git_merge_trees(int index_only, + struct tree *common, + struct tree *head, + struct tree *merge) +{ + int rc; + struct tree_desc t[3]; + 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; + opts.src_index = &the_index; + opts.dst_index = &the_index; + setup_unpack_trees_porcelain(&opts, "merge"); + + init_tree_desc_from_tree(t+0, common); + init_tree_desc_from_tree(t+1, head); + init_tree_desc_from_tree(t+2, merge); + + rc = unpack_trees(3, t, &opts); + cache_tree_free(&active_cache_tree); + return rc; +} + +struct tree *write_tree_from_memory(struct merge_options *o) +{ + struct tree *result = NULL; + + if (unmerged_cache()) { + int i; + fprintf(stderr, "BUG: There are unmerged index entries:\n"); + for (i = 0; i < active_nr; i++) { + const struct cache_entry *ce = active_cache[i]; + if (ce_stage(ce)) + fprintf(stderr, "BUG: %d %.*s\n", ce_stage(ce), + (int)ce_namelen(ce), ce->name); + } + die("BUG: unmerged index entries in merge-recursive.c"); + } + + if (!active_cache_tree) + active_cache_tree = cache_tree(); + + if (!cache_tree_fully_valid(active_cache_tree) && + cache_tree_update(&the_index, 0) < 0) { + err(o, _("error building trees")); + return NULL; + } + + result = lookup_tree(&active_cache_tree->oid); + + return result; +} + +static int save_files_dirs(const unsigned char *sha1, + struct strbuf *base, const char *path, + unsigned int mode, int stage, void *context) +{ + struct path_hashmap_entry *entry; + int baselen = base->len; + struct merge_options *o = context; + + strbuf_addstr(base, path); + + FLEX_ALLOC_MEM(entry, path, base->buf, base->len); + hashmap_entry_init(entry, path_hash(entry->path)); + hashmap_add(&o->current_file_dir_set, entry); + + strbuf_setlen(base, baselen); + return (S_ISDIR(mode) ? READ_TREE_RECURSIVE : 0); +} + +static void get_files_dirs(struct merge_options *o, struct tree *tree) +{ + struct pathspec match_all; + memset(&match_all, 0, sizeof(match_all)); + read_tree_recursive(tree, "", 0, 0, &match_all, save_files_dirs, o); +} + +/* + * Returns an 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 string_list *entries) +{ + struct string_list_item *item; + struct stage_data *e = xcalloc(1, sizeof(struct stage_data)); + get_tree_entry(o->object.oid.hash, path, + e->stages[1].oid.hash, &e->stages[1].mode); + get_tree_entry(a->object.oid.hash, path, + e->stages[2].oid.hash, &e->stages[2].mode); + get_tree_entry(b->object.oid.hash, path, + e->stages[3].oid.hash, &e->stages[3].mode); + item = string_list_insert(entries, path); + 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 string_list *get_unmerged(void) +{ + struct string_list *unmerged = xcalloc(1, sizeof(struct string_list)); + int i; + + unmerged->strdup_strings = 1; + + for (i = 0; i < active_nr; i++) { + struct string_list_item *item; + struct stage_data *e; + const struct cache_entry *ce = active_cache[i]; + if (!ce_stage(ce)) + continue; + + item = string_list_lookup(unmerged, ce->name); + if (!item) { + item = string_list_insert(unmerged, ce->name); + item->util = xcalloc(1, sizeof(struct stage_data)); + } + e = item->util; + e->stages[ce_stage(ce)].mode = ce->ce_mode; + oidcpy(&e->stages[ce_stage(ce)].oid, &ce->oid); + } + + return unmerged; +} + +static int string_list_df_name_compare(const char *one, const char *two) +{ + int onelen = strlen(one); + int twolen = strlen(two); + /* + * Here we only care that entries for D/F conflicts are + * adjacent, in particular with the file of the D/F conflict + * appearing before files below the corresponding directory. + * The order of the rest of the list is irrelevant for us. + * + * To achieve this, we sort with df_name_compare and provide + * the mode S_IFDIR so that D/F conflicts will sort correctly. + * We use the mode S_IFDIR for everything else for simplicity, + * since in other cases any changes in their order due to + * sorting cause no problems for us. + */ + int cmp = df_name_compare(one, onelen, S_IFDIR, + two, twolen, S_IFDIR); + /* + * Now that 'foo' and 'foo/bar' compare equal, we have to make sure + * that 'foo' comes before 'foo/bar'. + */ + if (cmp) + return cmp; + return onelen - twolen; +} + +static void record_df_conflict_files(struct merge_options *o, + struct string_list *entries) +{ + /* If there is a D/F conflict and the file for such a conflict + * currently exist in the working tree, we want to allow it to be + * removed to make room for the corresponding directory if needed. + * The files underneath the directories of such D/F conflicts will + * be processed before the corresponding file involved in the D/F + * conflict. If the D/F directory ends up being removed by the + * merge, then we won't have to touch the D/F file. If the D/F + * directory needs to be written to the working copy, then the D/F + * file will simply be removed (in make_room_for_path()) to make + * room for the necessary paths. Note that if both the directory + * and the file need to be present, then the D/F file will be + * reinstated with a new unique name at the time it is processed. + */ + struct string_list df_sorted_entries = STRING_LIST_INIT_NODUP; + const char *last_file = NULL; + int last_len = 0; + int i; + + /* + * If we're merging merge-bases, we don't want to bother with + * any working directory changes. + */ + if (o->call_depth) + return; + + /* Ensure D/F conflicts are adjacent in the entries list. */ + for (i = 0; i < entries->nr; i++) { + struct string_list_item *next = &entries->items[i]; + string_list_append(&df_sorted_entries, next->string)->util = + next->util; + } + df_sorted_entries.cmp = string_list_df_name_compare; + string_list_sort(&df_sorted_entries); + + string_list_clear(&o->df_conflict_file_set, 1); + for (i = 0; i < df_sorted_entries.nr; i++) { + const char *path = df_sorted_entries.items[i].string; + int len = strlen(path); + struct stage_data *e = df_sorted_entries.items[i].util; + + /* + * Check if last_file & path correspond to a D/F conflict; + * i.e. whether path is last_file+'/'+<something>. + * If so, record that it's okay to remove last_file to make + * room for path and friends if needed. + */ + if (last_file && + len > last_len && + memcmp(path, last_file, last_len) == 0 && + path[last_len] == '/') { + string_list_insert(&o->df_conflict_file_set, last_file); + } + + /* + * Determine whether path could exist as a file in the + * working directory as a possible D/F conflict. This + * will only occur when it exists in stage 2 as a + * file. + */ + if (S_ISREG(e->stages[2].mode) || S_ISLNK(e->stages[2].mode)) { + last_file = path; + last_len = len; + } else { + last_file = NULL; + } + } + string_list_clear(&df_sorted_entries, 0); +} + +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 string_list *get_renames(struct merge_options *o, + struct tree *tree, + struct tree *o_tree, + struct tree *a_tree, + struct tree *b_tree, + struct string_list *entries) +{ + int i; + struct string_list *renames; + struct diff_options opts; + + renames = xcalloc(1, sizeof(struct string_list)); + if (!o->detect_rename) + return renames; + + diff_setup(&opts); + DIFF_OPT_SET(&opts, RECURSIVE); + DIFF_OPT_CLR(&opts, RENAME_EMPTY); + opts.detect_rename = DIFF_DETECT_RENAME; + opts.rename_limit = o->merge_rename_limit >= 0 ? o->merge_rename_limit : + o->diff_rename_limit >= 0 ? o->diff_rename_limit : + 1000; + opts.rename_score = o->rename_score; + opts.show_rename_progress = o->show_rename_progress; + opts.output_format = DIFF_FORMAT_NO_OUTPUT; + diff_setup_done(&opts); + diff_tree_oid(&o_tree->object.oid, &tree->object.oid, "", &opts); + diffcore_std(&opts); + if (opts.needed_rename_limit > o->needed_rename_limit) + o->needed_rename_limit = opts.needed_rename_limit; + for (i = 0; i < diff_queued_diff.nr; ++i) { + struct string_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 = string_list_lookup(entries, re->pair->one->path); + 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 = string_list_lookup(entries, re->pair->two->path); + 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 = string_list_insert(renames, pair->one->path); + item->util = re; + } + opts.output_format = DIFF_FORMAT_NO_OUTPUT; + diff_queued_diff.nr = 0; + diff_flush(&opts); + return renames; +} + +static int update_stages(struct merge_options *opt, const char *path, + const struct diff_filespec *o, + const struct diff_filespec *a, + const struct diff_filespec *b) +{ + + /* + * NOTE: It is usually a bad idea to call update_stages on a path + * before calling update_file on that same path, since it can + * sometimes lead to spurious "refusing to lose untracked file..." + * messages from update_file (via make_room_for path via + * would_lose_untracked). Instead, reverse the order of the calls + * (executing update_file first and then update_stages). + */ + int clear = 1; + int options = ADD_CACHE_OK_TO_ADD | ADD_CACHE_SKIP_DFCHECK; + if (clear) + if (remove_file_from_cache(path)) + return -1; + if (o) + if (add_cacheinfo(opt, o->mode, &o->oid, path, 1, 0, options)) + return -1; + if (a) + if (add_cacheinfo(opt, a->mode, &a->oid, path, 2, 0, options)) + return -1; + if (b) + if (add_cacheinfo(opt, b->mode, &b->oid, path, 3, 0, options)) + return -1; + return 0; +} + +static void update_entry(struct stage_data *entry, + struct diff_filespec *o, + struct diff_filespec *a, + struct diff_filespec *b) +{ + entry->processed = 0; + entry->stages[1].mode = o->mode; + entry->stages[2].mode = a->mode; + entry->stages[3].mode = b->mode; + oidcpy(&entry->stages[1].oid, &o->oid); + oidcpy(&entry->stages[2].oid, &a->oid); + oidcpy(&entry->stages[3].oid, &b->oid); +} + +static int remove_file(struct merge_options *o, int clean, + const char *path, int no_wd) +{ + int update_cache = o->call_depth || clean; + int update_working_directory = !o->call_depth && !no_wd; + + if (update_cache) { + if (remove_file_from_cache(path)) + return -1; + } + if (update_working_directory) { + if (ignore_case) { + struct cache_entry *ce; + ce = cache_file_exists(path, strlen(path), ignore_case); + if (ce && ce_stage(ce) == 0) + return 0; + } + if (remove_path(path)) + return -1; + } + return 0; +} + +/* add a string to a strbuf, but converting "/" to "_" */ +static void add_flattened_path(struct strbuf *out, const char *s) +{ + size_t i = out->len; + strbuf_addstr(out, s); + for (; i < out->len; i++) + if (out->buf[i] == '/') + out->buf[i] = '_'; +} + +static char *unique_path(struct merge_options *o, const char *path, const char *branch) +{ + struct path_hashmap_entry *entry; + struct strbuf newpath = STRBUF_INIT; + int suffix = 0; + size_t base_len; + + strbuf_addf(&newpath, "%s~", path); + add_flattened_path(&newpath, branch); + + base_len = newpath.len; + while (hashmap_get_from_hash(&o->current_file_dir_set, + path_hash(newpath.buf), newpath.buf) || + (!o->call_depth && file_exists(newpath.buf))) { + strbuf_setlen(&newpath, base_len); + strbuf_addf(&newpath, "_%d", suffix++); + } + + FLEX_ALLOC_MEM(entry, path, newpath.buf, newpath.len); + hashmap_entry_init(entry, path_hash(entry->path)); + hashmap_add(&o->current_file_dir_set, entry); + return strbuf_detach(&newpath, NULL); +} + +/** + * Check whether a directory in the index is in the way of an incoming + * file. Return 1 if so. If check_working_copy is non-zero, also + * check the working directory. If empty_ok is non-zero, also return + * 0 in the case where the working-tree dir exists but is empty. + */ +static int dir_in_way(const char *path, int check_working_copy, int empty_ok) +{ + int pos; + struct strbuf dirpath = STRBUF_INIT; + struct stat st; + + strbuf_addstr(&dirpath, path); + strbuf_addch(&dirpath, '/'); + + pos = cache_name_pos(dirpath.buf, dirpath.len); + + if (pos < 0) + pos = -1 - pos; + if (pos < active_nr && + !strncmp(dirpath.buf, active_cache[pos]->name, dirpath.len)) { + strbuf_release(&dirpath); + return 1; + } + + strbuf_release(&dirpath); + return check_working_copy && !lstat(path, &st) && S_ISDIR(st.st_mode) && + !(empty_ok && is_empty_dir(path)); +} + +static int was_tracked(const char *path) +{ + int pos = cache_name_pos(path, strlen(path)); + + if (0 <= pos) + /* we have been tracking this path */ + return 1; + + /* + * Look for an unmerged entry for the path, + * specifically stage #2, which would indicate + * that "our" side before the merge started + * had the path tracked (and resulted in a conflict). + */ + for (pos = -1 - pos; + pos < active_nr && !strcmp(path, active_cache[pos]->name); + pos++) + if (ce_stage(active_cache[pos]) == 2) + return 1; + return 0; +} + +static int would_lose_untracked(const char *path) +{ + return !was_tracked(path) && file_exists(path); +} + +static int make_room_for_path(struct merge_options *o, const char *path) +{ + int status, i; + const char *msg = _("failed to create path '%s'%s"); + + /* Unlink any D/F conflict files that are in the way */ + for (i = 0; i < o->df_conflict_file_set.nr; i++) { + const char *df_path = o->df_conflict_file_set.items[i].string; + size_t pathlen = strlen(path); + size_t df_pathlen = strlen(df_path); + if (df_pathlen < pathlen && + path[df_pathlen] == '/' && + strncmp(path, df_path, df_pathlen) == 0) { + output(o, 3, + _("Removing %s to make room for subdirectory\n"), + df_path); + unlink(df_path); + unsorted_string_list_delete_item(&o->df_conflict_file_set, + i, 0); + break; + } + } + + /* Make sure leading directories are created */ + status = safe_create_leading_directories_const(path); + if (status) { + if (status == SCLD_EXISTS) + /* something else exists */ + return err(o, msg, path, _(": perhaps a D/F conflict?")); + return err(o, msg, path, ""); + } + + /* + * Do not unlink a file in the work tree if we are not + * tracking it. + */ + if (would_lose_untracked(path)) + return err(o, _("refusing to lose untracked file at '%s'"), + path); + + /* Successful unlink is good.. */ + if (!unlink(path)) + return 0; + /* .. and so is no existing file */ + if (errno == ENOENT) + return 0; + /* .. but not some other error (who really cares what?) */ + return err(o, msg, path, _(": perhaps a D/F conflict?")); +} + +static int update_file_flags(struct merge_options *o, + const struct object_id *oid, + unsigned mode, + const char *path, + int update_cache, + int update_wd) +{ + int ret = 0; + + if (o->call_depth) + update_wd = 0; + + if (update_wd) { + enum object_type type; + void *buf; + unsigned long size; + + if (S_ISGITLINK(mode)) { + /* + * We may later decide to recursively descend into + * the submodule directory and update its index + * and/or work tree, but we do not do that now. + */ + update_wd = 0; + goto update_index; + } + + buf = read_sha1_file(oid->hash, &type, &size); + if (!buf) + return err(o, _("cannot read object %s '%s'"), oid_to_hex(oid), path); + if (type != OBJ_BLOB) { + ret = err(o, _("blob expected for %s '%s'"), oid_to_hex(oid), path); + goto free_buf; + } + if (S_ISREG(mode)) { + struct strbuf strbuf = STRBUF_INIT; + if (convert_to_working_tree(path, buf, size, &strbuf)) { + free(buf); + size = strbuf.len; + buf = strbuf_detach(&strbuf, NULL); + } + } + + if (make_room_for_path(o, path) < 0) { + update_wd = 0; + goto free_buf; + } + if (S_ISREG(mode) || (!has_symlinks && S_ISLNK(mode))) { + int fd; + if (mode & 0100) + mode = 0777; + else + mode = 0666; + fd = open(path, O_WRONLY | O_TRUNC | O_CREAT, mode); + if (fd < 0) { + ret = err(o, _("failed to open '%s': %s"), + path, strerror(errno)); + goto free_buf; + } + write_in_full(fd, buf, size); + close(fd); + } else if (S_ISLNK(mode)) { + char *lnk = xmemdupz(buf, size); + safe_create_leading_directories_const(path); + unlink(path); + if (symlink(lnk, path)) + ret = err(o, _("failed to symlink '%s': %s"), + path, strerror(errno)); + free(lnk); + } else + ret = err(o, + _("do not know what to do with %06o %s '%s'"), + mode, oid_to_hex(oid), path); + free_buf: + free(buf); + } + update_index: + if (!ret && update_cache) + add_cacheinfo(o, mode, oid, path, 0, update_wd, ADD_CACHE_OK_TO_ADD); + return ret; +} + +static int update_file(struct merge_options *o, + int clean, + const struct object_id *oid, + unsigned mode, + const char *path) +{ + return update_file_flags(o, oid, mode, path, o->call_depth || clean, !o->call_depth); +} + +/* Low level file merging, update and removal */ + +struct merge_file_info { + struct object_id oid; + unsigned mode; + unsigned clean:1, + merge:1; +}; + +static int merge_3way(struct merge_options *o, + mmbuffer_t *result_buf, + const struct diff_filespec *one, + const struct diff_filespec *a, + const struct diff_filespec *b, + const char *branch1, + const char *branch2) +{ + mmfile_t orig, src1, src2; + struct ll_merge_options ll_opts = {0}; + char *base_name, *name1, *name2; + int merge_status; + + ll_opts.renormalize = o->renormalize; + ll_opts.xdl_opts = o->xdl_opts; + + if (o->call_depth) { + ll_opts.virtual_ancestor = 1; + ll_opts.variant = 0; + } else { + switch (o->recursive_variant) { + case MERGE_RECURSIVE_OURS: + ll_opts.variant = XDL_MERGE_FAVOR_OURS; + break; + case MERGE_RECURSIVE_THEIRS: + ll_opts.variant = XDL_MERGE_FAVOR_THEIRS; + break; + default: + ll_opts.variant = 0; + break; + } + } + + if (strcmp(a->path, b->path) || + (o->ancestor != NULL && strcmp(a->path, one->path) != 0)) { + base_name = o->ancestor == NULL ? NULL : + mkpathdup("%s:%s", o->ancestor, one->path); + name1 = mkpathdup("%s:%s", branch1, a->path); + name2 = mkpathdup("%s:%s", branch2, b->path); + } else { + base_name = o->ancestor == NULL ? NULL : + mkpathdup("%s", o->ancestor); + name1 = mkpathdup("%s", branch1); + name2 = mkpathdup("%s", branch2); + } + + read_mmblob(&orig, &one->oid); + read_mmblob(&src1, &a->oid); + read_mmblob(&src2, &b->oid); + + merge_status = ll_merge(result_buf, a->path, &orig, base_name, + &src1, name1, &src2, name2, &ll_opts); + + free(base_name); + free(name1); + free(name2); + free(orig.ptr); + free(src1.ptr); + free(src2.ptr); + return merge_status; +} + +static int merge_file_1(struct merge_options *o, + const struct diff_filespec *one, + const struct diff_filespec *a, + const 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; + oidcpy(&result->oid, &a->oid); + } else { + result->mode = b->mode; + oidcpy(&result->oid, &b->oid); + } + } else { + if (!oid_eq(&a->oid, &one->oid) && !oid_eq(&b->oid, &one->oid)) + result->merge = 1; + + /* + * Merge modes + */ + if (a->mode == b->mode || a->mode == one->mode) + result->mode = b->mode; + else { + result->mode = a->mode; + if (b->mode != one->mode) { + result->clean = 0; + result->merge = 1; + } + } + + if (oid_eq(&a->oid, &b->oid) || oid_eq(&a->oid, &one->oid)) + oidcpy(&result->oid, &b->oid); + else if (oid_eq(&b->oid, &one->oid)) + oidcpy(&result->oid, &a->oid); + else if (S_ISREG(a->mode)) { + mmbuffer_t result_buf; + int ret = 0, merge_status; + + merge_status = merge_3way(o, &result_buf, one, a, b, + branch1, branch2); + + if ((merge_status < 0) || !result_buf.ptr) + ret = err(o, _("Failed to execute internal merge")); + + if (!ret && write_sha1_file(result_buf.ptr, result_buf.size, + blob_type, result->oid.hash)) + ret = err(o, _("Unable to add %s to database"), + a->path); + + free(result_buf.ptr); + if (ret) + return ret; + result->clean = (merge_status == 0); + } else if (S_ISGITLINK(a->mode)) { + result->clean = merge_submodule(&result->oid, + one->path, + &one->oid, + &a->oid, + &b->oid, + !o->call_depth); + } else if (S_ISLNK(a->mode)) { + oidcpy(&result->oid, &a->oid); + + if (!oid_eq(&a->oid, &b->oid)) + result->clean = 0; + } else + die("BUG: unsupported object type in the tree"); + } + + return 0; +} + +static int merge_file_special_markers(struct merge_options *o, + const struct diff_filespec *one, + const struct diff_filespec *a, + const struct diff_filespec *b, + const char *branch1, + const char *filename1, + const char *branch2, + const char *filename2, + struct merge_file_info *mfi) +{ + char *side1 = NULL; + char *side2 = NULL; + int ret; + + if (filename1) + side1 = xstrfmt("%s:%s", branch1, filename1); + if (filename2) + side2 = xstrfmt("%s:%s", branch2, filename2); + + ret = merge_file_1(o, one, a, b, + side1 ? side1 : branch1, + side2 ? side2 : branch2, mfi); + free(side1); + free(side2); + return ret; +} + +static int merge_file_one(struct merge_options *o, + const char *path, + const struct object_id *o_oid, int o_mode, + const struct object_id *a_oid, int a_mode, + const struct object_id *b_oid, int b_mode, + const char *branch1, + const char *branch2, + struct merge_file_info *mfi) +{ + struct diff_filespec one, a, b; + + one.path = a.path = b.path = (char *)path; + oidcpy(&one.oid, o_oid); + one.mode = o_mode; + oidcpy(&a.oid, a_oid); + a.mode = a_mode; + oidcpy(&b.oid, b_oid); + b.mode = b_mode; + return merge_file_1(o, &one, &a, &b, branch1, branch2, mfi); +} + +static int handle_change_delete(struct merge_options *o, + const char *path, const char *old_path, + const struct object_id *o_oid, int o_mode, + const struct object_id *changed_oid, + int changed_mode, + const char *change_branch, + const char *delete_branch, + const char *change, const char *change_past) +{ + char *alt_path = NULL; + const char *update_path = path; + int ret = 0; + + if (dir_in_way(path, !o->call_depth, 0)) { + update_path = alt_path = unique_path(o, path, change_branch); + } + + if (o->call_depth) { + /* + * We cannot arbitrarily accept either a_sha or b_sha as + * correct; since there is no true "middle point" between + * them, simply reuse the base version for virtual merge base. + */ + ret = remove_file_from_cache(path); + if (!ret) + ret = update_file(o, 0, o_oid, o_mode, update_path); + } else { + if (!alt_path) { + if (!old_path) { + output(o, 1, _("CONFLICT (%s/delete): %s deleted in %s " + "and %s in %s. Version %s of %s left in tree."), + change, path, delete_branch, change_past, + change_branch, change_branch, path); + } else { + output(o, 1, _("CONFLICT (%s/delete): %s deleted in %s " + "and %s to %s in %s. Version %s of %s left in tree."), + change, old_path, delete_branch, change_past, path, + change_branch, change_branch, path); + } + } else { + if (!old_path) { + output(o, 1, _("CONFLICT (%s/delete): %s deleted in %s " + "and %s in %s. Version %s of %s left in tree at %s."), + change, path, delete_branch, change_past, + change_branch, change_branch, path, alt_path); + } else { + output(o, 1, _("CONFLICT (%s/delete): %s deleted in %s " + "and %s to %s in %s. Version %s of %s left in tree at %s."), + change, old_path, delete_branch, change_past, path, + change_branch, change_branch, path, alt_path); + } + } + /* + * No need to call update_file() on path when change_branch == + * o->branch1 && !alt_path, since that would needlessly touch + * path. We could call update_file_flags() with update_cache=0 + * and update_wd=0, but that's a no-op. + */ + if (change_branch != o->branch1 || alt_path) + ret = update_file(o, 0, changed_oid, changed_mode, update_path); + } + free(alt_path); + + return ret; +} + +static int conflict_rename_delete(struct merge_options *o, + struct diff_filepair *pair, + const char *rename_branch, + const char *delete_branch) +{ + const struct diff_filespec *orig = pair->one; + const struct diff_filespec *dest = pair->two; + + if (handle_change_delete(o, + o->call_depth ? orig->path : dest->path, + o->call_depth ? NULL : orig->path, + &orig->oid, orig->mode, + &dest->oid, dest->mode, + rename_branch, delete_branch, + _("rename"), _("renamed"))) + return -1; + + if (o->call_depth) + return remove_file_from_cache(dest->path); + else + return update_stages(o, dest->path, NULL, + rename_branch == o->branch1 ? dest : NULL, + rename_branch == o->branch1 ? NULL : dest); +} + +static struct diff_filespec *filespec_from_entry(struct diff_filespec *target, + struct stage_data *entry, + int stage) +{ + struct object_id *oid = &entry->stages[stage].oid; + unsigned mode = entry->stages[stage].mode; + if (mode == 0 || is_null_oid(oid)) + return NULL; + oidcpy(&target->oid, oid); + target->mode = mode; + return target; +} + +static int handle_file(struct merge_options *o, + struct diff_filespec *rename, + int stage, + struct rename_conflict_info *ci) +{ + char *dst_name = rename->path; + struct stage_data *dst_entry; + const char *cur_branch, *other_branch; + struct diff_filespec other; + struct diff_filespec *add; + int ret; + + if (stage == 2) { + dst_entry = ci->dst_entry1; + cur_branch = ci->branch1; + other_branch = ci->branch2; + } else { + dst_entry = ci->dst_entry2; + cur_branch = ci->branch2; + other_branch = ci->branch1; + } + + add = filespec_from_entry(&other, dst_entry, stage ^ 1); + if (add) { + char *add_name = unique_path(o, rename->path, other_branch); + if (update_file(o, 0, &add->oid, add->mode, add_name)) + return -1; + + remove_file(o, 0, rename->path, 0); + dst_name = unique_path(o, rename->path, cur_branch); + } else { + if (dir_in_way(rename->path, !o->call_depth, 0)) { + dst_name = unique_path(o, rename->path, cur_branch); + output(o, 1, _("%s is a directory in %s adding as %s instead"), + rename->path, other_branch, dst_name); + } + } + if ((ret = update_file(o, 0, &rename->oid, rename->mode, dst_name))) + ; /* fall through, do allow dst_name to be released */ + else if (stage == 2) + ret = update_stages(o, rename->path, NULL, rename, add); + else + ret = update_stages(o, rename->path, NULL, add, rename); + + if (dst_name != rename->path) + free(dst_name); + + return ret; +} + +static int conflict_rename_rename_1to2(struct merge_options *o, + struct rename_conflict_info *ci) +{ + /* One file was renamed in both branches, but to different names. */ + struct diff_filespec *one = ci->pair1->one; + struct diff_filespec *a = ci->pair1->two; + struct diff_filespec *b = ci->pair2->two; + + output(o, 1, _("CONFLICT (rename/rename): " + "Rename \"%s\"->\"%s\" in branch \"%s\" " + "rename \"%s\"->\"%s\" in \"%s\"%s"), + one->path, a->path, ci->branch1, + one->path, b->path, ci->branch2, + o->call_depth ? _(" (left unresolved)") : ""); + if (o->call_depth) { + struct merge_file_info mfi; + struct diff_filespec other; + struct diff_filespec *add; + if (merge_file_one(o, one->path, + &one->oid, one->mode, + &a->oid, a->mode, + &b->oid, b->mode, + ci->branch1, ci->branch2, &mfi)) + return -1; + + /* + * FIXME: For rename/add-source conflicts (if we could detect + * such), this is wrong. We should instead find a unique + * pathname and then either rename the add-source file to that + * unique path, or use that unique path instead of src here. + */ + if (update_file(o, 0, &mfi.oid, mfi.mode, one->path)) + return -1; + + /* + * Above, we put the merged content at the merge-base's + * path. Now we usually need to delete both a->path and + * b->path. However, the rename on each side of the merge + * could also be involved in a rename/add conflict. In + * such cases, we should keep the added file around, + * resolving the conflict at that path in its favor. + */ + add = filespec_from_entry(&other, ci->dst_entry1, 2 ^ 1); + if (add) { + if (update_file(o, 0, &add->oid, add->mode, a->path)) + return -1; + } + else + remove_file_from_cache(a->path); + add = filespec_from_entry(&other, ci->dst_entry2, 3 ^ 1); + if (add) { + if (update_file(o, 0, &add->oid, add->mode, b->path)) + return -1; + } + else + remove_file_from_cache(b->path); + } else if (handle_file(o, a, 2, ci) || handle_file(o, b, 3, ci)) + return -1; + + return 0; +} + +static int conflict_rename_rename_2to1(struct merge_options *o, + struct rename_conflict_info *ci) +{ + /* Two files, a & b, were renamed to the same thing, c. */ + struct diff_filespec *a = ci->pair1->one; + struct diff_filespec *b = ci->pair2->one; + struct diff_filespec *c1 = ci->pair1->two; + struct diff_filespec *c2 = ci->pair2->two; + char *path = c1->path; /* == c2->path */ + struct merge_file_info mfi_c1; + struct merge_file_info mfi_c2; + int ret; + + output(o, 1, _("CONFLICT (rename/rename): " + "Rename %s->%s in %s. " + "Rename %s->%s in %s"), + a->path, c1->path, ci->branch1, + b->path, c2->path, ci->branch2); + + remove_file(o, 1, a->path, o->call_depth || would_lose_untracked(a->path)); + remove_file(o, 1, b->path, o->call_depth || would_lose_untracked(b->path)); + + if (merge_file_special_markers(o, a, c1, &ci->ren1_other, + o->branch1, c1->path, + o->branch2, ci->ren1_other.path, &mfi_c1) || + merge_file_special_markers(o, b, &ci->ren2_other, c2, + o->branch1, ci->ren2_other.path, + o->branch2, c2->path, &mfi_c2)) + return -1; + + if (o->call_depth) { + /* + * If mfi_c1.clean && mfi_c2.clean, then it might make + * sense to do a two-way merge of those results. But, I + * think in all cases, it makes sense to have the virtual + * merge base just undo the renames; they can be detected + * again later for the non-recursive merge. + */ + remove_file(o, 0, path, 0); + ret = update_file(o, 0, &mfi_c1.oid, mfi_c1.mode, a->path); + if (!ret) + ret = update_file(o, 0, &mfi_c2.oid, mfi_c2.mode, + b->path); + } else { + char *new_path1 = unique_path(o, path, ci->branch1); + char *new_path2 = unique_path(o, path, ci->branch2); + output(o, 1, _("Renaming %s to %s and %s to %s instead"), + a->path, new_path1, b->path, new_path2); + remove_file(o, 0, path, 0); + ret = update_file(o, 0, &mfi_c1.oid, mfi_c1.mode, new_path1); + if (!ret) + ret = update_file(o, 0, &mfi_c2.oid, mfi_c2.mode, + new_path2); + free(new_path2); + free(new_path1); + } + + return ret; +} + +static int process_renames(struct merge_options *o, + struct string_list *a_renames, + struct string_list *b_renames) +{ + int clean_merge = 1, i, j; + struct string_list a_by_dst = STRING_LIST_INIT_NODUP; + struct string_list b_by_dst = STRING_LIST_INIT_NODUP; + const struct rename *sre; + + for (i = 0; i < a_renames->nr; i++) { + sre = a_renames->items[i].util; + string_list_insert(&a_by_dst, sre->pair->two->path)->util + = (void *)sre; + } + for (i = 0; i < b_renames->nr; i++) { + sre = b_renames->items[i].util; + string_list_insert(&b_by_dst, sre->pair->two->path)->util + = (void *)sre; + } + + for (i = 0, j = 0; i < a_renames->nr || j < b_renames->nr;) { + struct string_list *renames1, *renames2Dst; + struct rename *ren1 = NULL, *ren2 = NULL; + const char *branch1, *branch2; + const char *ren1_src, *ren1_dst; + struct string_list_item *lookup; + + if (i >= a_renames->nr) { + ren2 = b_renames->items[j++].util; + } else if (j >= b_renames->nr) { + ren1 = a_renames->items[i++].util; + } else { + int compare = strcmp(a_renames->items[i].string, + b_renames->items[j].string); + 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; + renames2Dst = &b_by_dst; + branch1 = o->branch1; + branch2 = o->branch2; + } else { + renames1 = b_renames; + renames2Dst = &a_by_dst; + branch1 = o->branch2; + branch2 = o->branch1; + SWAP(ren2, ren1); + } + + if (ren1->processed) + continue; + ren1->processed = 1; + ren1->dst_entry->processed = 1; + /* BUG: We should only mark src_entry as processed if we + * are not dealing with a rename + add-source case. + */ + ren1->src_entry->processed = 1; + + ren1_src = ren1->pair->one->path; + ren1_dst = ren1->pair->two->path; + + if (ren2) { + /* One file renamed on both sides */ + const char *ren2_src = ren2->pair->one->path; + const char *ren2_dst = ren2->pair->two->path; + enum rename_type rename_type; + if (strcmp(ren1_src, ren2_src) != 0) + die("BUG: ren1_src != ren2_src"); + ren2->dst_entry->processed = 1; + ren2->processed = 1; + if (strcmp(ren1_dst, ren2_dst) != 0) { + rename_type = RENAME_ONE_FILE_TO_TWO; + clean_merge = 0; + } else { + rename_type = RENAME_ONE_FILE_TO_ONE; + /* BUG: We should only remove ren1_src in + * the base stage (think of rename + + * add-source cases). + */ + remove_file(o, 1, ren1_src, 1); + update_entry(ren1->dst_entry, + ren1->pair->one, + ren1->pair->two, + ren2->pair->two); + } + setup_rename_conflict_info(rename_type, + ren1->pair, + ren2->pair, + branch1, + branch2, + ren1->dst_entry, + ren2->dst_entry, + o, + NULL, + NULL); + } else if ((lookup = string_list_lookup(renames2Dst, ren1_dst))) { + /* Two different files renamed to the same thing */ + char *ren2_dst; + ren2 = lookup->util; + ren2_dst = ren2->pair->two->path; + if (strcmp(ren1_dst, ren2_dst) != 0) + die("BUG: ren1_dst != ren2_dst"); + + clean_merge = 0; + ren2->processed = 1; + /* + * BUG: We should only mark src_entry as processed + * if we are not dealing with a rename + add-source + * case. + */ + ren2->src_entry->processed = 1; + + setup_rename_conflict_info(RENAME_TWO_FILES_TO_ONE, + ren1->pair, + ren2->pair, + branch1, + branch2, + ren1->dst_entry, + ren2->dst_entry, + o, + ren1->src_entry, + ren2->src_entry); + + } else { + /* Renamed in 1, maybe changed in 2 */ + /* we only use sha1 and mode of these */ + struct diff_filespec src_other, dst_other; + int try_merge; + + /* + * unpack_trees loads entries from common-commit + * into stage 1, from head-commit into stage 2, and + * from merge-commit into stage 3. We keep track + * of which side corresponds to the rename. + */ + int renamed_stage = a_renames == renames1 ? 2 : 3; + int other_stage = a_renames == renames1 ? 3 : 2; + + /* BUG: We should only remove ren1_src in the base + * stage and in other_stage (think of rename + + * add-source case). + */ + remove_file(o, 1, ren1_src, + renamed_stage == 2 || !was_tracked(ren1_src)); + + oidcpy(&src_other.oid, + &ren1->src_entry->stages[other_stage].oid); + src_other.mode = ren1->src_entry->stages[other_stage].mode; + oidcpy(&dst_other.oid, + &ren1->dst_entry->stages[other_stage].oid); + dst_other.mode = ren1->dst_entry->stages[other_stage].mode; + try_merge = 0; + + if (oid_eq(&src_other.oid, &null_oid)) { + setup_rename_conflict_info(RENAME_DELETE, + ren1->pair, + NULL, + branch1, + branch2, + ren1->dst_entry, + NULL, + o, + NULL, + NULL); + } else if ((dst_other.mode == ren1->pair->two->mode) && + oid_eq(&dst_other.oid, &ren1->pair->two->oid)) { + /* + * Added file on the other side identical to + * the file being renamed: clean merge. + * Also, there is no need to overwrite the + * file already in the working copy, so call + * update_file_flags() instead of + * update_file(). + */ + if (update_file_flags(o, + &ren1->pair->two->oid, + ren1->pair->two->mode, + ren1_dst, + 1, /* update_cache */ + 0 /* update_wd */)) + clean_merge = -1; + } else if (!oid_eq(&dst_other.oid, &null_oid)) { + clean_merge = 0; + try_merge = 1; + output(o, 1, _("CONFLICT (rename/add): Rename %s->%s in %s. " + "%s added in %s"), + ren1_src, ren1_dst, branch1, + ren1_dst, branch2); + if (o->call_depth) { + struct merge_file_info mfi; + if (merge_file_one(o, ren1_dst, &null_oid, 0, + &ren1->pair->two->oid, + ren1->pair->two->mode, + &dst_other.oid, + dst_other.mode, + branch1, branch2, &mfi)) { + clean_merge = -1; + goto cleanup_and_return; + } + output(o, 1, _("Adding merged %s"), ren1_dst); + if (update_file(o, 0, &mfi.oid, + mfi.mode, ren1_dst)) + clean_merge = -1; + try_merge = 0; + } else { + char *new_path = unique_path(o, ren1_dst, branch2); + output(o, 1, _("Adding as %s instead"), new_path); + if (update_file(o, 0, &dst_other.oid, + dst_other.mode, new_path)) + clean_merge = -1; + free(new_path); + } + } else + try_merge = 1; + + if (clean_merge < 0) + goto cleanup_and_return; + if (try_merge) { + struct diff_filespec *one, *a, *b; + src_other.path = (char *)ren1_src; + + one = ren1->pair->one; + if (a_renames == renames1) { + a = ren1->pair->two; + b = &src_other; + } else { + b = ren1->pair->two; + a = &src_other; + } + update_entry(ren1->dst_entry, one, a, b); + setup_rename_conflict_info(RENAME_NORMAL, + ren1->pair, + NULL, + branch1, + NULL, + ren1->dst_entry, + NULL, + o, + NULL, + NULL); + } + } + } +cleanup_and_return: + string_list_clear(&a_by_dst, 0); + string_list_clear(&b_by_dst, 0); + + return clean_merge; +} + +static struct object_id *stage_oid(const struct object_id *oid, unsigned mode) +{ + return (is_null_oid(oid) || mode == 0) ? NULL: (struct object_id *)oid; +} + +static int read_oid_strbuf(struct merge_options *o, + const struct object_id *oid, struct strbuf *dst) +{ + void *buf; + enum object_type type; + unsigned long size; + buf = read_sha1_file(oid->hash, &type, &size); + if (!buf) + return err(o, _("cannot read object %s"), oid_to_hex(oid)); + if (type != OBJ_BLOB) { + free(buf); + return err(o, _("object %s is not a blob"), oid_to_hex(oid)); + } + strbuf_attach(dst, buf, size, size + 1); + return 0; +} + +static int blob_unchanged(struct merge_options *opt, + const struct object_id *o_oid, + unsigned o_mode, + const struct object_id *a_oid, + unsigned a_mode, + int renormalize, const char *path) +{ + struct strbuf o = STRBUF_INIT; + struct strbuf a = STRBUF_INIT; + int ret = 0; /* assume changed for safety */ + + if (a_mode != o_mode) + return 0; + if (oid_eq(o_oid, a_oid)) + return 1; + if (!renormalize) + return 0; + + assert(o_oid && a_oid); + if (read_oid_strbuf(opt, o_oid, &o) || read_oid_strbuf(opt, a_oid, &a)) + goto error_return; + /* + * Note: binary | is used so that both renormalizations are + * performed. Comparison can be skipped if both files are + * unchanged since their sha1s have already been compared. + */ + if (renormalize_buffer(&the_index, path, o.buf, o.len, &o) | + renormalize_buffer(&the_index, path, a.buf, a.len, &a)) + ret = (o.len == a.len && !memcmp(o.buf, a.buf, o.len)); + +error_return: + strbuf_release(&o); + strbuf_release(&a); + return ret; +} + +static int handle_modify_delete(struct merge_options *o, + const char *path, + struct object_id *o_oid, int o_mode, + struct object_id *a_oid, int a_mode, + struct object_id *b_oid, int b_mode) +{ + const char *modify_branch, *delete_branch; + struct object_id *changed_oid; + int changed_mode; + + if (a_oid) { + modify_branch = o->branch1; + delete_branch = o->branch2; + changed_oid = a_oid; + changed_mode = a_mode; + } else { + modify_branch = o->branch2; + delete_branch = o->branch1; + changed_oid = b_oid; + changed_mode = b_mode; + } + + return handle_change_delete(o, + path, NULL, + o_oid, o_mode, + changed_oid, changed_mode, + modify_branch, delete_branch, + _("modify"), _("modified")); +} + +static int merge_content(struct merge_options *o, + const char *path, + struct object_id *o_oid, int o_mode, + struct object_id *a_oid, int a_mode, + struct object_id *b_oid, int b_mode, + struct rename_conflict_info *rename_conflict_info) +{ + const char *reason = _("content"); + const char *path1 = NULL, *path2 = NULL; + struct merge_file_info mfi; + struct diff_filespec one, a, b; + unsigned df_conflict_remains = 0; + + if (!o_oid) { + reason = _("add/add"); + o_oid = (struct object_id *)&null_oid; + } + one.path = a.path = b.path = (char *)path; + oidcpy(&one.oid, o_oid); + one.mode = o_mode; + oidcpy(&a.oid, a_oid); + a.mode = a_mode; + oidcpy(&b.oid, b_oid); + b.mode = b_mode; + + if (rename_conflict_info) { + struct diff_filepair *pair1 = rename_conflict_info->pair1; + + path1 = (o->branch1 == rename_conflict_info->branch1) ? + pair1->two->path : pair1->one->path; + /* If rename_conflict_info->pair2 != NULL, we are in + * RENAME_ONE_FILE_TO_ONE case. Otherwise, we have a + * normal rename. + */ + path2 = (rename_conflict_info->pair2 || + o->branch2 == rename_conflict_info->branch1) ? + pair1->two->path : pair1->one->path; + + if (dir_in_way(path, !o->call_depth, + S_ISGITLINK(pair1->two->mode))) + df_conflict_remains = 1; + } + if (merge_file_special_markers(o, &one, &a, &b, + o->branch1, path1, + o->branch2, path2, &mfi)) + return -1; + + if (mfi.clean && !df_conflict_remains && + oid_eq(&mfi.oid, a_oid) && mfi.mode == a_mode) { + int path_renamed_outside_HEAD; + output(o, 3, _("Skipped %s (merged same as existing)"), path); + /* + * The content merge resulted in the same file contents we + * already had. We can return early if those file contents + * are recorded at the correct path (which may not be true + * if the merge involves a rename). + */ + path_renamed_outside_HEAD = !path2 || !strcmp(path, path2); + if (!path_renamed_outside_HEAD) { + add_cacheinfo(o, mfi.mode, &mfi.oid, path, + 0, (!o->call_depth), 0); + return mfi.clean; + } + } else + output(o, 2, _("Auto-merging %s"), path); + + if (!mfi.clean) { + if (S_ISGITLINK(mfi.mode)) + reason = _("submodule"); + output(o, 1, _("CONFLICT (%s): Merge conflict in %s"), + reason, path); + if (rename_conflict_info && !df_conflict_remains) + if (update_stages(o, path, &one, &a, &b)) + return -1; + } + + if (df_conflict_remains) { + char *new_path; + if (o->call_depth) { + remove_file_from_cache(path); + } else { + if (!mfi.clean) { + if (update_stages(o, path, &one, &a, &b)) + return -1; + } else { + int file_from_stage2 = was_tracked(path); + struct diff_filespec merged; + oidcpy(&merged.oid, &mfi.oid); + merged.mode = mfi.mode; + + if (update_stages(o, path, NULL, + file_from_stage2 ? &merged : NULL, + file_from_stage2 ? NULL : &merged)) + return -1; + } + + } + new_path = unique_path(o, path, rename_conflict_info->branch1); + output(o, 1, _("Adding as %s instead"), new_path); + if (update_file(o, 0, &mfi.oid, mfi.mode, new_path)) { + free(new_path); + return -1; + } + free(new_path); + mfi.clean = 0; + } else if (update_file(o, mfi.clean, &mfi.oid, mfi.mode, path)) + return -1; + return mfi.clean; +} + +/* Per entry merge function */ +static int process_entry(struct merge_options *o, + const char *path, struct stage_data *entry) +{ + int clean_merge = 1; + int normalize = o->renormalize; + unsigned o_mode = entry->stages[1].mode; + unsigned a_mode = entry->stages[2].mode; + unsigned b_mode = entry->stages[3].mode; + struct object_id *o_oid = stage_oid(&entry->stages[1].oid, o_mode); + struct object_id *a_oid = stage_oid(&entry->stages[2].oid, a_mode); + struct object_id *b_oid = stage_oid(&entry->stages[3].oid, b_mode); + + entry->processed = 1; + if (entry->rename_conflict_info) { + struct rename_conflict_info *conflict_info = entry->rename_conflict_info; + switch (conflict_info->rename_type) { + case RENAME_NORMAL: + case RENAME_ONE_FILE_TO_ONE: + clean_merge = merge_content(o, path, + o_oid, o_mode, a_oid, a_mode, b_oid, b_mode, + conflict_info); + break; + case RENAME_DELETE: + clean_merge = 0; + if (conflict_rename_delete(o, + conflict_info->pair1, + conflict_info->branch1, + conflict_info->branch2)) + clean_merge = -1; + break; + case RENAME_ONE_FILE_TO_TWO: + clean_merge = 0; + if (conflict_rename_rename_1to2(o, conflict_info)) + clean_merge = -1; + break; + case RENAME_TWO_FILES_TO_ONE: + clean_merge = 0; + if (conflict_rename_rename_2to1(o, conflict_info)) + clean_merge = -1; + break; + default: + entry->processed = 0; + break; + } + } else if (o_oid && (!a_oid || !b_oid)) { + /* Case A: Deleted in one */ + if ((!a_oid && !b_oid) || + (!b_oid && blob_unchanged(o, o_oid, o_mode, a_oid, a_mode, normalize, path)) || + (!a_oid && blob_unchanged(o, o_oid, o_mode, b_oid, b_mode, normalize, path))) { + /* Deleted in both or deleted in one and + * unchanged in the other */ + if (a_oid) + output(o, 2, _("Removing %s"), path); + /* do not touch working file if it did not exist */ + remove_file(o, 1, path, !a_oid); + } else { + /* Modify/delete; deleted side may have put a directory in the way */ + clean_merge = 0; + if (handle_modify_delete(o, path, o_oid, o_mode, + a_oid, a_mode, b_oid, b_mode)) + clean_merge = -1; + } + } else if ((!o_oid && a_oid && !b_oid) || + (!o_oid && !a_oid && b_oid)) { + /* Case B: Added in one. */ + /* [nothing|directory] -> ([nothing|directory], file) */ + + const char *add_branch; + const char *other_branch; + unsigned mode; + const struct object_id *oid; + const char *conf; + + if (a_oid) { + add_branch = o->branch1; + other_branch = o->branch2; + mode = a_mode; + oid = a_oid; + conf = _("file/directory"); + } else { + add_branch = o->branch2; + other_branch = o->branch1; + mode = b_mode; + oid = b_oid; + conf = _("directory/file"); + } + if (dir_in_way(path, !o->call_depth, + S_ISGITLINK(a_mode))) { + char *new_path = unique_path(o, path, add_branch); + clean_merge = 0; + output(o, 1, _("CONFLICT (%s): There is a directory with name %s in %s. " + "Adding %s as %s"), + conf, path, other_branch, path, new_path); + if (update_file(o, 0, oid, mode, new_path)) + clean_merge = -1; + else if (o->call_depth) + remove_file_from_cache(path); + free(new_path); + } else { + output(o, 2, _("Adding %s"), path); + /* do not overwrite file if already present */ + if (update_file_flags(o, oid, mode, path, 1, !a_oid)) + clean_merge = -1; + } + } else if (a_oid && b_oid) { + /* Case C: Added in both (check for same permissions) and */ + /* case D: Modified in both, but differently. */ + clean_merge = merge_content(o, path, + o_oid, o_mode, a_oid, a_mode, b_oid, b_mode, + NULL); + } else if (!o_oid && !a_oid && !b_oid) { + /* + * this entry was deleted altogether. a_mode == 0 means + * we had that path and want to actively remove it. + */ + remove_file(o, 1, path, !a_mode); + } else + die("BUG: fatal merge failure, shouldn't happen."); + + return clean_merge; +} + +int merge_trees(struct merge_options *o, + struct tree *head, + struct tree *merge, + struct tree *common, + struct tree **result) +{ + int code, clean; + + if (o->subtree_shift) { + merge = shift_tree_object(head, merge, o->subtree_shift); + common = shift_tree_object(head, common, o->subtree_shift); + } + + if (oid_eq(&common->object.oid, &merge->object.oid)) { + output(o, 0, _("Already up to date!")); + *result = head; + return 1; + } + + code = git_merge_trees(o->call_depth, common, head, merge); + + if (code != 0) { + if (show(o, 4) || o->call_depth) + err(o, _("merging of trees %s and %s failed"), + oid_to_hex(&head->object.oid), + oid_to_hex(&merge->object.oid)); + return -1; + } + + if (unmerged_cache()) { + struct string_list *entries, *re_head, *re_merge; + int i; + /* + * Only need the hashmap while processing entries, so + * initialize it here and free it when we are done running + * through the entries. Keeping it in the merge_options as + * opposed to decaring a local hashmap is for convenience + * so that we don't have to pass it to around. + */ + hashmap_init(&o->current_file_dir_set, path_hashmap_cmp, NULL, 512); + get_files_dirs(o, head); + get_files_dirs(o, merge); + + entries = get_unmerged(); + record_df_conflict_files(o, entries); + re_head = get_renames(o, head, common, head, merge, entries); + re_merge = get_renames(o, merge, common, head, merge, entries); + clean = process_renames(o, re_head, re_merge); + if (clean < 0) + goto cleanup; + for (i = entries->nr-1; 0 <= i; i--) { + const char *path = entries->items[i].string; + struct stage_data *e = entries->items[i].util; + if (!e->processed) { + int ret = process_entry(o, path, e); + if (!ret) + clean = 0; + else if (ret < 0) { + clean = ret; + goto cleanup; + } + } + } + for (i = 0; i < entries->nr; i++) { + struct stage_data *e = entries->items[i].util; + if (!e->processed) + die("BUG: unprocessed path??? %s", + entries->items[i].string); + } + +cleanup: + string_list_clear(re_merge, 0); + string_list_clear(re_head, 0); + string_list_clear(entries, 1); + + hashmap_free(&o->current_file_dir_set, 1); + + free(re_merge); + free(re_head); + free(entries); + + if (clean < 0) + return clean; + } + else + clean = 1; + + if (o->call_depth && !(*result = write_tree_from_memory(o))) + return -1; + + 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. + */ +int merge_recursive(struct merge_options *o, + struct commit *h1, + struct commit *h2, + struct commit_list *ca, + struct commit **result) +{ + struct commit_list *iter; + struct commit *merged_common_ancestors; + struct tree *mrtree = mrtree; + int clean; + + if (show(o, 4)) { + output(o, 4, _("Merging:")); + output_commit_title(o, h1); + output_commit_title(o, h2); + } + + if (!ca) { + ca = get_merge_bases(h1, h2); + ca = reverse_commit_list(ca); + } + + if (show(o, 5)) { + unsigned cnt = commit_list_count(ca); + + output(o, 5, Q_("found %u common ancestor:", + "found %u common ancestors:", cnt), cnt); + for (iter = ca; iter; iter = iter->next) + output_commit_title(o, iter->item); + } + + merged_common_ancestors = pop_commit(&ca); + if (merged_common_ancestors == NULL) { + /* if there is no common ancestor, use an empty tree */ + struct tree *tree; + + tree = lookup_tree(&empty_tree_oid); + merged_common_ancestors = make_virtual_commit(tree, "ancestor"); + } + + for (iter = ca; iter; iter = iter->next) { + const char *saved_b1, *saved_b2; + o->call_depth++; + /* + * When the merge fails, the result contains files + * with conflict markers. The cleanness flag is + * ignored (unless indicating an error), it was never + * actually used, as result of merge_trees has always + * overwritten it: the committed "conflicts" were + * already resolved. + */ + discard_cache(); + saved_b1 = o->branch1; + saved_b2 = o->branch2; + o->branch1 = "Temporary merge branch 1"; + o->branch2 = "Temporary merge branch 2"; + if (merge_recursive(o, merged_common_ancestors, iter->item, + NULL, &merged_common_ancestors) < 0) + return -1; + o->branch1 = saved_b1; + o->branch2 = saved_b2; + o->call_depth--; + + if (!merged_common_ancestors) + return err(o, _("merge returned no commit")); + } + + discard_cache(); + if (!o->call_depth) + read_cache(); + + o->ancestor = "merged common ancestors"; + clean = merge_trees(o, h1->tree, h2->tree, merged_common_ancestors->tree, + &mrtree); + if (clean < 0) { + flush_output(o); + return clean; + } + + if (o->call_depth) { + *result = make_virtual_commit(mrtree, "merged tree"); + commit_list_insert(h1, &(*result)->parents); + commit_list_insert(h2, &(*result)->parents->next); + } + flush_output(o); + if (!o->call_depth && o->buffer_output < 2) + strbuf_release(&o->obuf); + if (show(o, 2)) + diff_warn_rename_limit("merge.renamelimit", + o->needed_rename_limit, 0); + return clean; +} + +static struct commit *get_ref(const struct object_id *oid, const char *name) +{ + struct object *object; + + object = deref_tag(parse_object(oid), name, strlen(name)); + if (!object) + return NULL; + if (object->type == OBJ_TREE) + return make_virtual_commit((struct tree*)object, name); + if (object->type != OBJ_COMMIT) + return NULL; + if (parse_commit((struct commit *)object)) + return NULL; + return (struct commit *)object; +} + +int merge_recursive_generic(struct merge_options *o, + const struct object_id *head, + const struct object_id *merge, + int num_base_list, + const struct object_id **base_list, + struct commit **result) +{ + int clean; + struct lock_file *lock = xcalloc(1, sizeof(struct lock_file)); + struct commit *head_commit = get_ref(head, o->branch1); + struct commit *next_commit = get_ref(merge, o->branch2); + struct commit_list *ca = NULL; + + if (base_list) { + int i; + for (i = 0; i < num_base_list; ++i) { + struct commit *base; + if (!(base = get_ref(base_list[i], oid_to_hex(base_list[i])))) + return err(o, _("Could not parse object '%s'"), + oid_to_hex(base_list[i])); + commit_list_insert(base, &ca); + } + } + + hold_locked_index(lock, LOCK_DIE_ON_ERROR); + clean = merge_recursive(o, head_commit, next_commit, ca, + result); + if (clean < 0) + return clean; + + if (active_cache_changed && + write_locked_index(&the_index, lock, COMMIT_LOCK)) + return err(o, _("Unable to write index.")); + + return clean ? 0 : 1; +} + +static void merge_recursive_config(struct merge_options *o) +{ + git_config_get_int("merge.verbosity", &o->verbosity); + git_config_get_int("diff.renamelimit", &o->diff_rename_limit); + git_config_get_int("merge.renamelimit", &o->merge_rename_limit); + git_config(git_xmerge_config, NULL); +} + +void init_merge_options(struct merge_options *o) +{ + memset(o, 0, sizeof(struct merge_options)); + o->verbosity = 2; + o->buffer_output = 1; + o->diff_rename_limit = -1; + o->merge_rename_limit = -1; + o->renormalize = 0; + o->detect_rename = 1; + merge_recursive_config(o); + if (getenv("GIT_MERGE_VERBOSITY")) + o->verbosity = + strtol(getenv("GIT_MERGE_VERBOSITY"), NULL, 10); + if (o->verbosity >= 5) + o->buffer_output = 0; + strbuf_init(&o->obuf, 0); + string_list_init(&o->df_conflict_file_set, 1); +} + +int parse_merge_opt(struct merge_options *o, const char *s) +{ + const char *arg; + + if (!s || !*s) + return -1; + if (!strcmp(s, "ours")) + o->recursive_variant = MERGE_RECURSIVE_OURS; + else if (!strcmp(s, "theirs")) + o->recursive_variant = MERGE_RECURSIVE_THEIRS; + else if (!strcmp(s, "subtree")) + o->subtree_shift = ""; + else if (skip_prefix(s, "subtree=", &arg)) + o->subtree_shift = arg; + else if (!strcmp(s, "patience")) + o->xdl_opts = DIFF_WITH_ALG(o, PATIENCE_DIFF); + else if (!strcmp(s, "histogram")) + o->xdl_opts = DIFF_WITH_ALG(o, HISTOGRAM_DIFF); + else if (skip_prefix(s, "diff-algorithm=", &arg)) { + long value = parse_algorithm_value(arg); + if (value < 0) + return -1; + /* clear out previous settings */ + DIFF_XDL_CLR(o, NEED_MINIMAL); + o->xdl_opts &= ~XDF_DIFF_ALGORITHM_MASK; + o->xdl_opts |= value; + } + else if (!strcmp(s, "ignore-space-change")) + DIFF_XDL_SET(o, IGNORE_WHITESPACE_CHANGE); + else if (!strcmp(s, "ignore-all-space")) + DIFF_XDL_SET(o, IGNORE_WHITESPACE); + else if (!strcmp(s, "ignore-space-at-eol")) + DIFF_XDL_SET(o, IGNORE_WHITESPACE_AT_EOL); + else if (!strcmp(s, "renormalize")) + o->renormalize = 1; + else if (!strcmp(s, "no-renormalize")) + o->renormalize = 0; + else if (!strcmp(s, "no-renames")) + o->detect_rename = 0; + else if (!strcmp(s, "find-renames")) { + o->detect_rename = 1; + o->rename_score = 0; + } + else if (skip_prefix(s, "find-renames=", &arg) || + skip_prefix(s, "rename-threshold=", &arg)) { + if ((o->rename_score = parse_rename_score(&arg)) == -1 || *arg != 0) + return -1; + o->detect_rename = 1; + } + else + return -1; + return 0; +} |