diff options
Diffstat (limited to 'merge-recursive.c')
| -rw-r--r-- | merge-recursive.c | 1790 |
1 files changed, 1790 insertions, 0 deletions
diff --git a/merge-recursive.c b/merge-recursive.c new file mode 100644 index 0000000000..42d52cb5bc --- /dev/null +++ b/merge-recursive.c @@ -0,0 +1,1790 @@ +/* + * 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 "advice.h" +#include "cache.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" + +static struct tree *shift_tree_object(struct tree *one, struct tree *two, + const char *subtree_shift) +{ + unsigned char shifted[20]; + + if (!*subtree_shift) { + shift_tree(one->object.sha1, two->object.sha1, shifted, 0); + } else { + shift_tree_by(one->object.sha1, two->object.sha1, shifted, + subtree_shift); + } + if (!hashcmp(two->object.sha1, shifted)) + return two; + return lookup_tree(shifted); +} + +/* + * A virtual commit has (const char *)commit->util set to the name. + */ + +static struct commit *make_virtual_commit(struct tree *tree, const char *comment) +{ + struct commit *commit = xcalloc(1, sizeof(struct commit)); + commit->tree = tree; + commit->util = (void*)comment; + /* 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; +} + +enum rename_type { + RENAME_NORMAL = 0, + RENAME_DELETE, + RENAME_ONE_FILE_TO_TWO +}; + +struct rename_df_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; +}; + +/* + * 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]; + struct rename_df_conflict_info *rename_df_conflict_info; + unsigned processed:1; +}; + +static inline void setup_rename_df_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 rename_df_conflict_info *ci = xcalloc(1, sizeof(struct rename_df_conflict_info)); + ci->rename_type = rename_type; + ci->pair1 = pair1; + ci->branch1 = branch1; + ci->branch2 = branch2; + + ci->dst_entry1 = dst_entry1; + dst_entry1->rename_df_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_df_conflict_info = ci; + dst_entry2->processed = 0; + } +} + +static int show(struct merge_options *o, int v) +{ + return (!o->call_depth && o->verbosity >= v) || o->verbosity >= 5; +} + +static void flush_output(struct merge_options *o) +{ + if (o->obuf.len) { + fputs(o->obuf.buf, stdout); + strbuf_reset(&o->obuf); + } +} + +__attribute__((format (printf, 3, 4))) +static void output(struct merge_options *o, int v, const char *fmt, ...) +{ + int len; + va_list ap; + + if (!show(o, v)) + return; + + strbuf_grow(&o->obuf, o->call_depth * 2 + 2); + memset(o->obuf.buf + o->obuf.len, ' ', o->call_depth * 2); + strbuf_setlen(&o->obuf, o->obuf.len + o->call_depth * 2); + + va_start(ap, fmt); + len = vsnprintf(o->obuf.buf + o->obuf.len, strbuf_avail(&o->obuf), fmt, ap); + va_end(ap); + + if (len < 0) + len = 0; + if (len >= strbuf_avail(&o->obuf)) { + strbuf_grow(&o->obuf, len + 2); + va_start(ap, fmt); + len = vsnprintf(o->obuf.buf + o->obuf.len, strbuf_avail(&o->obuf), fmt, ap); + va_end(ap); + if (len >= strbuf_avail(&o->obuf)) { + die("this should not happen, your snprintf is broken"); + } + } + strbuf_setlen(&o->obuf, o->obuf.len + len); + strbuf_add(&o->obuf, "\n", 1); + if (!o->buffer_output) + flush_output(o); +} + +static void output_commit_title(struct merge_options *o, struct commit *commit) +{ + int i; + flush_output(o); + for (i = o->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 *title; + int len = find_commit_subject(commit->buffer, &title); + if (len) + printf("%.*s\n", len, title); + } + } +} + +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); +} + +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++) { + struct cache_entry *ce = active_cache[i]; + if (ce_stage(ce)) + fprintf(stderr, "BUG: %d %.*s", ce_stage(ce), + (int)ce_namelen(ce), ce->name); + } + die("Bug in merge-recursive.c"); + } + + 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, void *context) +{ + int len = strlen(path); + char *newpath = xmalloc(baselen + len + 1); + struct merge_options *o = context; + + memcpy(newpath, base, baselen); + memcpy(newpath + baselen, path, len); + newpath[baselen + len] = '\0'; + + if (S_ISDIR(mode)) + string_list_insert(&o->current_directory_set, newpath); + else + string_list_insert(&o->current_file_set, newpath); + free(newpath); + + return (S_ISDIR(mode) ? READ_TREE_RECURSIVE : 0); +} + +static int get_files_dirs(struct merge_options *o, struct tree *tree) +{ + int n; + if (read_tree_recursive(tree, "", 0, 0, NULL, save_files_dirs, o)) + return 0; + n = o->current_file_set.nr + o->current_directory_set.nr; + return n; +} + +/* + * 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.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 = 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; + 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; + hashcpy(e->stages[ce_stage(ce)].sha, ce->sha1); + } + + return unmerged; +} + +static void make_room_for_directories_of_df_conflicts(struct merge_options *o, + struct string_list *entries) +{ + /* If there are D/F conflicts, and the paths currently exist + * in the working copy as a file, we want to remove them to + * make room for the corresponding directory. Such paths will + * later be processed in process_df_entry() at the end. If + * the corresponding directory ends up being removed by the + * merge, then the file will be reinstated at that time; + * otherwise, if the file is not supposed to be removed by the + * merge, the contents of the file will be placed in another + * unique filename. + * + * NOTE: This function relies on the fact that entries for a + * D/F conflict will appear adjacent in the index, with the + * entries for the file appearing before entries for paths + * below the corresponding directory. + */ + const char *last_file = NULL; + int last_len = 0; + struct stage_data *last_e; + int i; + + for (i = 0; i < entries->nr; i++) { + const char *path = entries->items[i].string; + int len = strlen(path); + struct stage_data *e = 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, remove last_file to make room for path and friends. + */ + if (last_file && + len > last_len && + memcmp(path, last_file, last_len) == 0 && + path[last_len] == '/') { + output(o, 3, "Removing %s to make room for subdirectory; may re-add later.", last_file); + unlink(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; + last_e = e; + } else { + last_file = NULL; + } + } +} + +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)); + diff_setup(&opts); + DIFF_OPT_SET(&opts, RECURSIVE); + 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 : + 500; + opts.rename_score = o->rename_score; + opts.warn_on_too_large_rename = 1; + 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 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_options(const char *path, struct diff_filespec *o, + struct diff_filespec *a, struct diff_filespec *b, + int clear, int options) +{ + 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 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; + return update_stages_options(path, o, a, b, clear, options); +} + +static int update_stages_and_entry(const char *path, + struct stage_data *entry, + struct diff_filespec *o, + struct diff_filespec *a, + struct diff_filespec *b, + int clear) +{ + int options; + + entry->processed = 0; + entry->stages[1].mode = o->mode; + entry->stages[2].mode = a->mode; + entry->stages[3].mode = b->mode; + hashcpy(entry->stages[1].sha, o->sha1); + hashcpy(entry->stages[2].sha, a->sha1); + hashcpy(entry->stages[3].sha, b->sha1); + options = ADD_CACHE_OK_TO_ADD | ADD_CACHE_SKIP_DFCHECK; + return update_stages_options(path, o, a, b, clear, options); +} + +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 (remove_path(path)) + return -1; + } + return 0; +} + +static char *unique_path(struct merge_options *o, 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 (string_list_has_string(&o->current_file_set, newpath) || + string_list_has_string(&o->current_directory_set, newpath) || + lstat(newpath, &st) == 0) + sprintf(p, "_%d", suffix++); + + string_list_insert(&o->current_file_set, newpath); + return newpath; +} + +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_errno("merge-recursive"); + } else if (!ret) { + die("merge-recursive: disk full?"); + } + size -= ret; + buf += ret; + } +} + +static int would_lose_untracked(const char *path) +{ + int pos = cache_name_pos(path, strlen(path)); + + if (pos < 0) + pos = -1 - pos; + while (pos < active_nr && + !strcmp(path, active_cache[pos]->name)) { + /* + * If stage #0, it is definitely tracked. + * If it has stage #2 then it was tracked + * before this merge started. All other + * cases the path was not tracked. + */ + switch (ce_stage(active_cache[pos])) { + case 0: + case 2: + return 0; + } + pos++; + } + return file_exists(path); +} + +static int make_room_for_path(const char *path) +{ + int status; + const char *msg = "failed to create path '%s'%s"; + + status = safe_create_leading_directories_const(path); + if (status) { + if (status == -3) { + /* something else exists */ + error(msg, path, ": perhaps a D/F conflict?"); + return -1; + } + die(msg, path, ""); + } + + /* + * Do not unlink a file in the work tree if we are not + * tracking it. + */ + if (would_lose_untracked(path)) + return error("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 error(msg, path, ": perhaps a D/F conflict?"); +} + +static void update_file_flags(struct merge_options *o, + const unsigned char *sha, + unsigned mode, + const char *path, + int update_cache, + int update_wd) +{ + 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(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)) { + 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(path) < 0) { + update_wd = 0; + free(buf); + goto update_index; + } + 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) + die_errno("failed to open '%s'", path); + flush_buffer(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)) + die_errno("failed to symlink '%s'", path); + free(lnk); + } else + die("do not know what to do with %06o %s '%s'", + mode, sha1_to_hex(sha), path); + free(buf); + } + update_index: + if (update_cache) + add_cacheinfo(mode, sha, path, 0, update_wd, ADD_CACHE_OK_TO_ADD); +} + +static void update_file(struct merge_options *o, + int clean, + const unsigned char *sha, + unsigned mode, + const char *path) +{ + update_file_flags(o, sha, mode, path, o->call_depth || clean, !o->call_depth); +} + +/* Low level file merging, update and removal */ + +struct merge_file_info { + unsigned char sha[20]; + unsigned mode; + unsigned clean:1, + merge:1; +}; + +static int merge_3way(struct merge_options *o, + mmbuffer_t *result_buf, + struct diff_filespec *one, + struct diff_filespec *a, + 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 : + xstrdup(mkpath("%s:%s", o->ancestor, one->path)); + name1 = xstrdup(mkpath("%s:%s", branch1, a->path)); + name2 = xstrdup(mkpath("%s:%s", branch2, b->path)); + } else { + base_name = o->ancestor == NULL ? NULL : + xstrdup(mkpath("%s", o->ancestor)); + name1 = xstrdup(mkpath("%s", branch1)); + name2 = xstrdup(mkpath("%s", branch2)); + } + + read_mmblob(&orig, one->sha1); + read_mmblob(&src1, a->sha1); + read_mmblob(&src2, b->sha1); + + merge_status = ll_merge(result_buf, a->path, &orig, base_name, + &src1, name1, &src2, name2, &ll_opts); + + free(name1); + free(name2); + free(orig.ptr); + free(src1.ptr); + free(src2.ptr); + return merge_status; +} + +static struct merge_file_info merge_file(struct merge_options *o, + struct diff_filespec *one, + 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, one->sha1) && !sha_eq(b->sha1, one->sha1)) + 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 (sha_eq(a->sha1, b->sha1) || sha_eq(a->sha1, one->sha1)) + hashcpy(result.sha, b->sha1); + else if (sha_eq(b->sha1, one->sha1)) + hashcpy(result.sha, a->sha1); + else if (S_ISREG(a->mode)) { + mmbuffer_t result_buf; + int merge_status; + + merge_status = merge_3way(o, &result_buf, one, a, b, + branch1, branch2); + + 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_ISGITLINK(a->mode)) { + result.clean = merge_submodule(result.sha, one->path, one->sha1, + a->sha1, b->sha1); + } else if (S_ISLNK(a->mode)) { + hashcpy(result.sha, a->sha1); + + if (!sha_eq(a->sha1, b->sha1)) + result.clean = 0; + } else { + die("unsupported object type in the tree"); + } + } + + return result; +} + +static void conflict_rename_delete(struct merge_options *o, + struct diff_filepair *pair, + const char *rename_branch, + const char *other_branch) +{ + char *dest_name = pair->two->path; + int df_conflict = 0; + struct stat st; + + output(o, 1, "CONFLICT (rename/delete): Rename %s->%s in %s " + "and deleted in %s", + pair->one->path, pair->two->path, rename_branch, + other_branch); + if (!o->call_depth) + update_stages(dest_name, NULL, + rename_branch == o->branch1 ? pair->two : NULL, + rename_branch == o->branch1 ? NULL : pair->two, + 1); + if (lstat(dest_name, &st) == 0 && S_ISDIR(st.st_mode)) { + dest_name = unique_path(o, dest_name, rename_branch); + df_conflict = 1; + } + update_file(o, 0, pair->two->sha1, pair->two->mode, dest_name); + if (df_conflict) + free(dest_name); +} + +static void conflict_rename_rename_1to2(struct merge_options *o, + struct diff_filepair *pair1, + const char *branch1, + struct diff_filepair *pair2, + const char *branch2) +{ + /* One file was renamed in both branches, but to different names. */ + char *del[2]; + int delp = 0; + const char *ren1_dst = pair1->two->path; + const char *ren2_dst = pair2->two->path; + const char *dst_name1 = ren1_dst; + const char *dst_name2 = ren2_dst; + struct stat st; + if (lstat(ren1_dst, &st) == 0 && S_ISDIR(st.st_mode)) { + dst_name1 = del[delp++] = unique_path(o, ren1_dst, branch1); + output(o, 1, "%s is a directory in %s adding as %s instead", + ren1_dst, branch2, dst_name1); + } + if (lstat(ren2_dst, &st) == 0 && S_ISDIR(st.st_mode)) { + dst_name2 = del[delp++] = unique_path(o, ren2_dst, branch2); + output(o, 1, "%s is a directory in %s adding as %s instead", + ren2_dst, branch1, dst_name2); + } + if (o->call_depth) { + remove_file_from_cache(dst_name1); + remove_file_from_cache(dst_name2); + /* + * Uncomment to leave the conflicting names in the resulting tree + * + * update_file(o, 0, pair1->two->sha1, pair1->two->mode, dst_name1); + * update_file(o, 0, pair2->two->sha1, pair2->two->mode, dst_name2); + */ + } else { + update_stages(ren1_dst, NULL, pair1->two, NULL, 1); + update_stages(ren2_dst, NULL, NULL, pair2->two, 1); + + update_file(o, 0, pair1->two->sha1, pair1->two->mode, dst_name1); + update_file(o, 0, pair2->two->sha1, pair2->two->mode, dst_name2); + } + while (delp--) + free(del[delp]); +} + +static void conflict_rename_rename_2to1(struct merge_options *o, + struct rename *ren1, + const char *branch1, + struct rename *ren2, + const char *branch2) +{ + /* Two files were renamed to the same thing. */ + char *new_path1 = unique_path(o, ren1->pair->two->path, branch1); + char *new_path2 = unique_path(o, ren2->pair->two->path, branch2); + output(o, 1, "Renaming %s to %s and %s to %s instead", + ren1->pair->one->path, new_path1, + ren2->pair->one->path, new_path2); + remove_file(o, 0, ren1->pair->two->path, 0); + update_file(o, 0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path1); + update_file(o, 0, ren2->pair->two->sha1, ren2->pair->two->mode, new_path2); + free(new_path2); + free(new_path1); +} + +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 + = sre->dst_entry; + } + 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 + = sre->dst_entry; + } + + for (i = 0, j = 0; i < a_renames->nr || j < b_renames->nr;) { + char *src; + struct string_list *renames1, *renames2Dst; + struct rename *ren1 = NULL, *ren2 = NULL; + const char *branch1, *branch2; + const char *ren1_src, *ren1_dst; + + 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 { + struct rename *tmp; + renames1 = b_renames; + renames2Dst = &a_by_dst; + branch1 = o->branch2; + branch2 = o->branch1; + 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) { + setup_rename_df_conflict_info(RENAME_ONE_FILE_TO_TWO, + ren1->pair, + ren2->pair, + branch1, + branch2, + ren1->dst_entry, + ren2->dst_entry); + } else { + remove_file(o, 1, ren1_src, 1); + update_stages_and_entry(ren1_dst, + ren1->dst_entry, + ren1->pair->one, + ren1->pair->two, + ren2->pair->two, + 1 /* clear */); + } + } else { + /* Renamed in 1, maybe changed in 2 */ + struct string_list_item *item; + /* 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; + + remove_file(o, 1, ren1_src, o->call_depth || renamed_stage == 2); + + hashcpy(src_other.sha1, ren1->src_entry->stages[other_stage].sha); + src_other.mode = ren1->src_entry->stages[other_stage].mode; + hashcpy(dst_other.sha1, ren1->dst_entry->stages[other_stage].sha); + dst_other.mode = ren1->dst_entry->stages[other_stage].mode; + try_merge = 0; + + if (sha_eq(src_other.sha1, null_sha1)) { + if (string_list_has_string(&o->current_directory_set, ren1_dst)) { + ren1->dst_entry->processed = 0; + setup_rename_df_conflict_info(RENAME_DELETE, + ren1->pair, + NULL, + branch1, + branch2, + ren1->dst_entry, + NULL); + } else { + clean_merge = 0; + conflict_rename_delete(o, ren1->pair, branch1, branch2); + } + } else if ((dst_other.mode == ren1->pair->two->mode) && + sha_eq(dst_other.sha1, ren1->pair->two->sha1)) { + /* Added file on the other side + identical to the file being + renamed: clean merge */ + update_file(o, 1, 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(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; + struct diff_filespec one, a, b; + + one.path = a.path = b.path = + (char *)ren1_dst; + hashcpy(one.sha1, null_sha1); + one.mode = 0; + hashcpy(a.sha1, ren1->pair->two->sha1); + a.mode = ren1->pair->two->mode; + hashcpy(b.sha1, dst_other.sha1); + b.mode = dst_other.mode; + mfi = merge_file(o, &one, &a, &b, + branch1, + branch2); + output(o, 1, "Adding merged %s", ren1_dst); + update_file(o, 0, + mfi.sha, + mfi.mode, + ren1_dst); + try_merge = 0; + } else { + new_path = unique_path(o, ren1_dst, branch2); + output(o, 1, "Adding as %s instead", new_path); + update_file(o, 0, dst_other.sha1, dst_other.mode, new_path); + } + } else if ((item = string_list_lookup(renames2Dst, ren1_dst))) { + ren2 = item->util; + clean_merge = 0; + ren2->processed = 1; + output(o, 1, "CONFLICT (rename/rename): " + "Rename %s->%s in %s. " + "Rename %s->%s in %s", + ren1_src, ren1_dst, branch1, + ren2->pair->one->path, ren2->pair->two->path, branch2); + conflict_rename_rename_2to1(o, ren1, branch1, ren2, branch2); + } else + try_merge = 1; + + 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_stages_and_entry(ren1_dst, ren1->dst_entry, one, a, b, 1); + if (string_list_has_string(&o->current_directory_set, ren1_dst)) { + setup_rename_df_conflict_info(RENAME_NORMAL, + ren1->pair, + NULL, + branch1, + NULL, + ren1->dst_entry, + NULL); + } + } + } + } + string_list_clear(&a_by_dst, 0); + string_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; +} + +static int read_sha1_strbuf(const unsigned char *sha1, struct strbuf *dst) +{ + void *buf; + enum object_type type; + unsigned long size; + buf = read_sha1_file(sha1, &type, &size); + if (!buf) + return error("cannot read object %s", sha1_to_hex(sha1)); + if (type != OBJ_BLOB) { + free(buf); + return error("object %s is not a blob", sha1_to_hex(sha1)); + } + strbuf_attach(dst, buf, size, size + 1); + return 0; +} + +static int blob_unchanged(const unsigned char *o_sha, + const unsigned char *a_sha, + int renormalize, const char *path) +{ + struct strbuf o = STRBUF_INIT; + struct strbuf a = STRBUF_INIT; + int ret = 0; /* assume changed for safety */ + + if (sha_eq(o_sha, a_sha)) + return 1; + if (!renormalize) + return 0; + + assert(o_sha && a_sha); + if (read_sha1_strbuf(o_sha, &o) || read_sha1_strbuf(a_sha, &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(path, o.buf, o.len, &o) | + renormalize_buffer(path, a.buf, o.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 void handle_delete_modify(struct merge_options *o, + const char *path, + const char *new_path, + unsigned char *a_sha, int a_mode, + unsigned char *b_sha, int b_mode) +{ + if (!a_sha) { + output(o, 1, "CONFLICT (delete/modify): %s deleted in %s " + "and modified in %s. Version %s of %s left in tree%s%s.", + path, o->branch1, + o->branch2, o->branch2, path, + path == new_path ? "" : " at ", + path == new_path ? "" : new_path); + update_file(o, 0, b_sha, b_mode, new_path); + } else { + output(o, 1, "CONFLICT (delete/modify): %s deleted in %s " + "and modified in %s. Version %s of %s left in tree%s%s.", + path, o->branch2, + o->branch1, o->branch1, path, + path == new_path ? "" : " at ", + path == new_path ? "" : new_path); + update_file(o, 0, a_sha, a_mode, new_path); + } +} + +static int merge_content(struct merge_options *o, + const char *path, + unsigned char *o_sha, int o_mode, + unsigned char *a_sha, int a_mode, + unsigned char *b_sha, int b_mode, + const char *df_rename_conflict_branch) +{ + const char *reason = "content"; + struct merge_file_info mfi; + struct diff_filespec one, a, b; + struct stat st; + unsigned df_conflict_remains = 0; + + if (!o_sha) { + reason = "add/add"; + o_sha = (unsigned char *)null_sha1; + } + one.path = a.path = b.path = (char *)path; + hashcpy(one.sha1, o_sha); + one.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, &one, &a, &b, o->branch1, o->branch2); + if (df_rename_conflict_branch && + lstat(path, &st) == 0 && S_ISDIR(st.st_mode)) { + df_conflict_remains = 1; + } + + if (mfi.clean && !df_conflict_remains && + sha_eq(mfi.sha, a_sha) && mfi.mode == a.mode) + output(o, 3, "Skipped %s (merged same as existing)", path); + 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 (df_conflict_remains) { + const char *new_path; + update_file_flags(o, mfi.sha, mfi.mode, path, + o->call_depth || mfi.clean, 0); + new_path = unique_path(o, path, df_rename_conflict_branch); + mfi.clean = 0; + output(o, 1, "Adding as %s instead", new_path); + update_file_flags(o, mfi.sha, mfi.mode, new_path, 0, 1); + } else { + update_file(o, mfi.clean, mfi.sha, mfi.mode, path); + } + return mfi.clean; + +} + +/* Per entry merge function */ +static int process_entry(struct merge_options *o, + const char *path, struct stage_data *entry) +{ + /* + printf("processing entry, clean cache: %s\n", index_only ? "yes": "no"); + print_index_entry("\tpath: ", 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; + 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 (entry->rename_df_conflict_info) + return 1; /* Such cases are handled elsewhere. */ + + entry->processed = 1; + if (o_sha && (!a_sha || !b_sha)) { + /* Case A: Deleted in one */ + if ((!a_sha && !b_sha) || + (!b_sha && blob_unchanged(o_sha, a_sha, normalize, path)) || + (!a_sha && blob_unchanged(o_sha, b_sha, normalize, path))) { + /* Deleted in both or deleted in one and + * unchanged in the other */ + if (a_sha) + output(o, 2, "Removing %s", path); + /* do not touch working file if it did not exist */ + remove_file(o, 1, path, !a_sha); + } else if (string_list_has_string(&o->current_directory_set, + path)) { + entry->processed = 0; + return 1; /* Assume clean until processed */ + } else { + /* Deleted in one and changed in the other */ + clean_merge = 0; + handle_delete_modify(o, path, path, + a_sha, a_mode, b_sha, b_mode); + } + + } else if ((!o_sha && a_sha && !b_sha) || + (!o_sha && !a_sha && b_sha)) { + /* Case B: Added in one. */ + unsigned mode; + const unsigned char *sha; + + if (a_sha) { + mode = a_mode; + sha = a_sha; + } else { + mode = b_mode; + sha = b_sha; + } + if (string_list_has_string(&o->current_directory_set, path)) { + /* Handle D->F conflicts after all subfiles */ + entry->processed = 0; + return 1; /* Assume clean until processed */ + } else { + output(o, 2, "Adding %s", path); + update_file(o, 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. */ + clean_merge = merge_content(o, path, + o_sha, o_mode, a_sha, a_mode, b_sha, b_mode, + NULL); + } 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(o, 1, path, !a_mode); + } else + die("Fatal merge failure, shouldn't happen."); + + return clean_merge; +} + +/* + * Per entry merge function for D/F (and/or rename) conflicts. In the + * cases we can cleanly resolve D/F conflicts, process_entry() can + * clean out all the files below the directory for us. All D/F + * conflict cases must be handled here at the end to make sure any + * directories that can be cleaned out, are. + * + * Some rename conflicts may also be handled here that don't necessarily + * involve D/F conflicts, since the code to handle them is generic enough + * to handle those rename conflicts with or without D/F conflicts also + * being involved. + */ +static int process_df_entry(struct merge_options *o, + const char *path, struct stage_data *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); + struct stat st; + + entry->processed = 1; + if (entry->rename_df_conflict_info) { + struct rename_df_conflict_info *conflict_info = entry->rename_df_conflict_info; + char *src; + switch (conflict_info->rename_type) { + case RENAME_NORMAL: + clean_merge = merge_content(o, path, + o_sha, o_mode, a_sha, a_mode, b_sha, b_mode, + conflict_info->branch1); + break; + case RENAME_DELETE: + clean_merge = 0; + conflict_rename_delete(o, conflict_info->pair1, + conflict_info->branch1, + conflict_info->branch2); + break; + case RENAME_ONE_FILE_TO_TWO: + src = conflict_info->pair1->one->path; + clean_merge = 0; + output(o, 1, "CONFLICT (rename/rename): " + "Rename \"%s\"->\"%s\" in branch \"%s\" " + "rename \"%s\"->\"%s\" in \"%s\"%s", + src, conflict_info->pair1->two->path, conflict_info->branch1, + src, conflict_info->pair2->two->path, conflict_info->branch2, + o->call_depth ? " (left unresolved)" : ""); + if (o->call_depth) { + remove_file_from_cache(src); + update_file(o, 0, conflict_info->pair1->one->sha1, + conflict_info->pair1->one->mode, src); + } + conflict_rename_rename_1to2(o, conflict_info->pair1, + conflict_info->branch1, + conflict_info->pair2, + conflict_info->branch2); + conflict_info->dst_entry2->processed = 1; + break; + default: + entry->processed = 0; + break; + } + } else if (o_sha && (!a_sha || !b_sha)) { + /* Modify/delete; deleted side may have put a directory in the way */ + const char *new_path = path; + if (lstat(path, &st) == 0 && S_ISDIR(st.st_mode)) + new_path = unique_path(o, path, a_sha ? o->branch1 : o->branch2); + clean_merge = 0; + handle_delete_modify(o, path, new_path, + a_sha, a_mode, b_sha, b_mode); + } else if (!o_sha && !!a_sha != !!b_sha) { + /* directory -> (directory, file) */ + const char *add_branch; + const char *other_branch; + unsigned mode; + const unsigned char *sha; + const char *conf; + + if (a_sha) { + add_branch = o->branch1; + other_branch = o->branch2; + mode = a_mode; + sha = a_sha; + conf = "file/directory"; + } else { + add_branch = o->branch2; + other_branch = o->branch1; + mode = b_mode; + sha = b_sha; + conf = "directory/file"; + } + if (lstat(path, &st) == 0 && S_ISDIR(st.st_mode)) { + const 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); + update_file(o, 0, sha, mode, new_path); + } else { + output(o, 2, "Adding %s", path); + update_file(o, 1, sha, mode, path); + } + } else { + entry->processed = 0; + return 1; /* not handled; assume clean until processed */ + } + + 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 (sha_eq(common->object.sha1, merge->object.sha1)) { + 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) + die("merging of trees %s and %s failed", + sha1_to_hex(head->object.sha1), + sha1_to_hex(merge->object.sha1)); + else + exit(128); + } + + if (unmerged_cache()) { + struct string_list *entries, *re_head, *re_merge; + int i; + string_list_clear(&o->current_file_set, 1); + string_list_clear(&o->current_directory_set, 1); + get_files_dirs(o, head); + get_files_dirs(o, merge); + + entries = get_unmerged(); + make_room_for_directories_of_df_conflicts(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); + for (i = 0; i < entries->nr; i++) { + const char *path = entries->items[i].string; + struct stage_data *e = entries->items[i].util; + if (!e->processed + && !process_entry(o, path, e)) + clean = 0; + } + for (i = 0; i < entries->nr; i++) { + const char *path = entries->items[i].string; + struct stage_data *e = entries->items[i].util; + if (!e->processed + && !process_df_entry(o, path, e)) + clean = 0; + } + for (i = 0; i < entries->nr; i++) { + struct stage_data *e = entries->items[i].util; + if (!e->processed) + die("Unprocessed path??? %s", + entries->items[i].string); + } + + string_list_clear(re_merge, 0); + string_list_clear(re_head, 0); + string_list_clear(entries, 1); + + } + else + clean = 1; + + if (o->call_depth) + *result = write_tree_from_memory(o); + + 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, 1); + ca = reverse_commit_list(ca); + } + + if (show(o, 5)) { + output(o, 5, "found %u common ancestor(s):", commit_list_count(ca)); + 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, 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) { + 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, 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"; + merge_recursive(o, merged_common_ancestors, iter->item, + NULL, &merged_common_ancestors); + o->branch1 = saved_b1; + o->branch2 = saved_b2; + o->call_depth--; + + if (!merged_common_ancestors) + die("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 (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); + return clean; +} + +static struct commit *get_ref(const unsigned char *sha1, const char *name) +{ + struct object *object; + + object = deref_tag(parse_object(sha1), 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 unsigned char *head, + const unsigned char *merge, + int num_base_list, + const unsigned char **base_list, + struct commit **result) +{ + int clean, index_fd; + 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], sha1_to_hex(base_list[i])))) + return error("Could not parse object '%s'", + sha1_to_hex(base_list[i])); + commit_list_insert(base, &ca); + } + } + + index_fd = hold_locked_index(lock, 1); + clean = merge_recursive(o, head_commit, next_commit, ca, + result); + if (active_cache_changed && + (write_cache(index_fd, active_cache, active_nr) || + commit_locked_index(lock))) + return error("Unable to write index."); + + return clean ? 0 : 1; +} + +static int merge_recursive_config(const char *var, const char *value, void *cb) +{ + struct merge_options *o = cb; + if (!strcasecmp(var, "merge.verbosity")) { + o->verbosity = git_config_int(var, value); + return 0; + } + if (!strcasecmp(var, "diff.renamelimit")) { + o->diff_rename_limit = git_config_int(var, value); + return 0; + } + if (!strcasecmp(var, "merge.renamelimit")) { + o->merge_rename_limit = git_config_int(var, value); + return 0; + } + return git_xmerge_config(var, value, cb); +} + +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; + git_config(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); + memset(&o->current_file_set, 0, sizeof(struct string_list)); + o->current_file_set.strdup_strings = 1; + memset(&o->current_directory_set, 0, sizeof(struct string_list)); + o->current_directory_set.strdup_strings = 1; +} + +int parse_merge_opt(struct merge_options *o, const char *s) +{ + 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 (!prefixcmp(s, "subtree=")) + o->subtree_shift = s + strlen("subtree="); + else if (!strcmp(s, "patience")) + o->xdl_opts |= XDF_PATIENCE_DIFF; + else if (!strcmp(s, "ignore-space-change")) + o->xdl_opts |= XDF_IGNORE_WHITESPACE_CHANGE; + else if (!strcmp(s, "ignore-all-space")) + o->xdl_opts |= XDF_IGNORE_WHITESPACE; + else if (!strcmp(s, "ignore-space-at-eol")) + o->xdl_opts |= XDF_IGNORE_WHITESPACE_AT_EOL; + else if (!strcmp(s, "renormalize")) + o->renormalize = 1; + else if (!strcmp(s, "no-renormalize")) + o->renormalize = 0; + else if (!prefixcmp(s, "rename-threshold=")) { + const char *score = s + strlen("rename-threshold="); + if ((o->rename_score = parse_rename_score(&score)) == -1 || *score != 0) + return -1; + } + else + return -1; + return 0; +} |