/* * Recursive Merge algorithm stolen from git-merge-recursive.py by * Fredrik Kuivinen. * The thieves were Alex Riesen and Johannes Schindelin, in June/July 2006 */ #include "cache.h" #include "cache-tree.h" #include "commit.h" #include "blob.h" #include "tree-walk.h" #include "diff.h" #include "diffcore.h" #include "run-command.h" #include "tag.h" #include "unpack-trees.h" #include "path-list.h" #include "xdiff-interface.h" #include "interpolate.h" #include "attr.h" static int subtree_merge; static struct tree *shift_tree_object(struct tree *one, struct tree *two) { unsigned char shifted[20]; /* * NEEDSWORK: this limits the recursion depth to hardcoded * value '2' to avoid excessive overhead. */ shift_tree(one->object.sha1, two->object.sha1, shifted, 2); if (!hashcmp(two->object.sha1, shifted)) return two; return lookup_tree(shifted); } /* * A virtual commit has * - (const char *)commit->util set to the name, and * - *(int *)commit->object.sha1 set to the virtual id. */ static unsigned commit_list_count(const struct commit_list *l) { unsigned c = 0; for (; l; l = l->next ) c++; return c; } static struct commit *make_virtual_commit(struct tree *tree, const char *comment) { struct commit *commit = xcalloc(1, sizeof(struct commit)); static unsigned virtual_id = 1; commit->tree = tree; commit->util = (void*)comment; *(int*)commit->object.sha1 = virtual_id++; /* avoid warnings */ commit->object.parsed = 1; return commit; } /* * Since we use get_tree_entry(), which does not put the read object into * the object pool, we cannot rely on a == b. */ static int sha_eq(const unsigned char *a, const unsigned char *b) { if (!a && !b) return 2; return a && b && hashcmp(a, b) == 0; } /* * Since we want to write the index eventually, we cannot reuse the index * for these (temporary) data. */ struct stage_data { struct { unsigned mode; unsigned char sha[20]; } stages[4]; unsigned processed:1; }; static struct path_list current_file_set = {NULL, 0, 0, 1}; static struct path_list current_directory_set = {NULL, 0, 0, 1}; static int call_depth = 0; static int verbosity = 2; static int rename_limit = -1; static int buffer_output = 1; static struct strbuf obuf = STRBUF_INIT; static int show(int v) { return (!call_depth && verbosity >= v) || verbosity >= 5; } static void flush_output(void) { if (obuf.len) { fputs(obuf.buf, stdout); strbuf_reset(&obuf); } } static void output(int v, const char *fmt, ...) { int len; va_list ap; if (!show(v)) return; strbuf_grow(&obuf, call_depth * 2 + 2); memset(obuf.buf + obuf.len, ' ', call_depth * 2); strbuf_setlen(&obuf, obuf.len + call_depth * 2); va_start(ap, fmt); len = vsnprintf(obuf.buf + obuf.len, strbuf_avail(&obuf), fmt, ap); va_end(ap); if (len < 0) len = 0; if (len >= strbuf_avail(&obuf)) { strbuf_grow(&obuf, len + 2); va_start(ap, fmt); len = vsnprintf(obuf.buf + obuf.len, strbuf_avail(&obuf), fmt, ap); va_end(ap); if (len >= strbuf_avail(&obuf)) { die("this should not happen, your snprintf is broken"); } } strbuf_setlen(&obuf, obuf.len + len); strbuf_add(&obuf, "\n", 1); if (!buffer_output) flush_output(); } static void output_commit_title(struct commit *commit) { int i; flush_output(); for (i = call_depth; i--;) fputs(" ", stdout); if (commit->util) printf("virtual %s\n", (char *)commit->util); else { printf("%s ", find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV)); if (parse_commit(commit) != 0) printf("(bad commit)\n"); else { const char *s; int len; for (s = commit->buffer; *s; s++) if (*s == '\n' && s[1] == '\n') { s += 2; break; } for (len = 0; s[len] && '\n' != s[len]; len++) ; /* do nothing */ printf("%.*s\n", len, s); } } } static int add_cacheinfo(unsigned int mode, const unsigned char *sha1, const char *path, int stage, int refresh, int options) { struct cache_entry *ce; ce = make_cache_entry(mode, sha1 ? sha1 : null_sha1, path, stage, refresh); if (!ce) return error("addinfo_cache failed for path '%s'", path); return add_cache_entry(ce, options); } /* * This is a global variable which is used in a number of places but * only written to in the 'merge' function. * * index_only == 1 => Don't leave any non-stage 0 entries in the cache and * don't update the working directory. * 0 => Leave unmerged entries in the cache and update * the working directory. */ static int index_only = 0; static 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; 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; } static int unmerged_index(void) { int i; for (i = 0; i < active_nr; i++) { struct cache_entry *ce = active_cache[i]; if (ce_stage(ce)) return 1; } return 0; } static struct tree *git_write_tree(void) { struct tree *result = NULL; if (unmerged_index()) { int i; output(0, "There are unmerged index entries:"); for (i = 0; i < active_nr; i++) { struct cache_entry *ce = active_cache[i]; if (ce_stage(ce)) output(0, "%d %.*s", ce_stage(ce), ce_namelen(ce), ce->name); } return NULL; } if (!active_cache_tree) active_cache_tree = cache_tree(); if (!cache_tree_fully_valid(active_cache_tree) && cache_tree_update(active_cache_tree, active_cache, active_nr, 0, 0) < 0) die("error building trees"); result = lookup_tree(active_cache_tree->sha1); return result; } static int save_files_dirs(const unsigned char *sha1, const char *base, int baselen, const char *path, unsigned int mode, int stage) { int len = strlen(path); char *newpath = xmalloc(baselen + len + 1); memcpy(newpath, base, baselen); memcpy(newpath + baselen, path, len); newpath[baselen + len] = '\0'; if (S_ISDIR(mode)) path_list_insert(newpath, ¤t_directory_set); else path_list_insert(newpath, ¤t_file_set); free(newpath); return READ_TREE_RECURSIVE; } static int get_files_dirs(struct tree *tree) { int n; if (read_tree_recursive(tree, "", 0, 0, NULL, save_files_dirs) != 0) return 0; n = current_file_set.nr + current_directory_set.nr; return n; } /* * Returns 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 path_list *entries) { struct path_list_item *item; struct stage_data *e = xcalloc(1, sizeof(struct stage_data)); get_tree_entry(o->object.sha1, path, e->stages[1].sha, &e->stages[1].mode); get_tree_entry(a->object.sha1, path, e->stages[2].sha, &e->stages[2].mode); get_tree_entry(b->object.sha1, path, e->stages[3].sha, &e->stages[3].mode); item = path_list_insert(path, entries); item->util = e; return e; } /* * Create a dictionary mapping file names to stage_data objects. The * dictionary contains one entry for every path with a non-zero stage entry. */ static struct path_list *get_unmerged(void) { struct path_list *unmerged = xcalloc(1, sizeof(struct path_list)); int i; unmerged->strdup_paths = 1; for (i = 0; i < active_nr; i++) { struct path_list_item *item; struct stage_data *e; struct cache_entry *ce = active_cache[i]; if (!ce_stage(ce)) continue; item = path_list_lookup(ce->name, unmerged); if (!item) { item = path_list_insert(ce->name, unmerged); item->util = xcalloc(1, sizeof(struct stage_data)); } e = item->util; e->stages[ce_stage(ce)].mode = ntohl(ce->ce_mode); hashcpy(e->stages[ce_stage(ce)].sha, ce->sha1); } return unmerged; } struct rename { struct diff_filepair *pair; struct stage_data *src_entry; struct stage_data *dst_entry; unsigned processed:1; }; /* * Get information of all renames which occurred between 'o_tree' and * 'tree'. We need the three trees in the merge ('o_tree', 'a_tree' and * 'b_tree') to be able to associate the correct cache entries with * the rename information. 'tree' is always equal to either a_tree or b_tree. */ static struct path_list *get_renames(struct tree *tree, struct tree *o_tree, struct tree *a_tree, struct tree *b_tree, struct path_list *entries) { int i; struct path_list *renames; struct diff_options opts; renames = xcalloc(1, sizeof(struct path_list)); diff_setup(&opts); DIFF_OPT_SET(&opts, RECURSIVE); opts.detect_rename = DIFF_DETECT_RENAME; opts.rename_limit = rename_limit; opts.output_format = DIFF_FORMAT_NO_OUTPUT; if (diff_setup_done(&opts) < 0) die("diff setup failed"); diff_tree_sha1(o_tree->object.sha1, tree->object.sha1, "", &opts); diffcore_std(&opts); for (i = 0; i < diff_queued_diff.nr; ++i) { struct path_list_item *item; struct rename *re; struct diff_filepair *pair = diff_queued_diff.queue[i]; if (pair->status != 'R') { diff_free_filepair(pair); continue; } re = xmalloc(sizeof(*re)); re->processed = 0; re->pair = pair; item = path_list_lookup(re->pair->one->path, entries); if (!item) re->src_entry = insert_stage_data(re->pair->one->path, o_tree, a_tree, b_tree, entries); else re->src_entry = item->util; item = path_list_lookup(re->pair->two->path, entries); if (!item) re->dst_entry = insert_stage_data(re->pair->two->path, o_tree, a_tree, b_tree, entries); else re->dst_entry = item->util; item = path_list_insert(pair->one->path, renames); item->util = re; } opts.output_format = DIFF_FORMAT_NO_OUTPUT; diff_queued_diff.nr = 0; diff_flush(&opts); return renames; } static int update_stages(const char *path, struct diff_filespec *o, struct diff_filespec *a, struct diff_filespec *b, int clear) { int options = ADD_CACHE_OK_TO_ADD | ADD_CACHE_OK_TO_REPLACE; if (clear) if (remove_file_from_cache(path)) return -1; if (o) if (add_cacheinfo(o->mode, o->sha1, path, 1, 0, options)) return -1; if (a) if (add_cacheinfo(a->mode, a->sha1, path, 2, 0, options)) return -1; if (b) if (add_cacheinfo(b->mode, b->sha1, path, 3, 0, options)) return -1; return 0; } static int remove_path(const char *name) { int ret; char *slash, *dirs; ret = unlink(name); if (ret) return ret; dirs = xstrdup(name); while ((slash = strrchr(name, '/'))) { *slash = '\0'; if (rmdir(name) != 0) break; } free(dirs); return ret; } static int remove_file(int clean, const char *path, int no_wd) { int update_cache = index_only || clean; int update_working_directory = !index_only && !no_wd; if (update_cache) { if (remove_file_from_cache(path)) return -1; } if (update_working_directory) { unlink(path); if (errno != ENOENT || errno != EISDIR) return -1; remove_path(path); } return 0; } static char *unique_path(const char *path, const char *branch) { char *newpath = xmalloc(strlen(path) + 1 + strlen(branch) + 8 + 1); int suffix = 0; struct stat st; char *p = newpath + strlen(path); strcpy(newpath, path); *(p++) = '~'; strcpy(p, branch); for (; *p; ++p) if ('/' == *p) *p = '_'; while (path_list_has_path(¤t_file_set, newpath) || path_list_has_path(¤t_directory_set, newpath) || lstat(newpath, &st) == 0) sprintf(p, "_%d", suffix++); path_list_insert(newpath, ¤t_file_set); return newpath; } static int mkdir_p(const char *path, unsigned long mode) { /* path points to cache entries, so xstrdup before messing with it */ char *buf = xstrdup(path); int result = safe_create_leading_directories(buf); free(buf); return result; } static void flush_buffer(int fd, const char *buf, unsigned long size) { while (size > 0) { long ret = write_in_full(fd, buf, size); if (ret < 0) { /* Ignore epipe */ if (errno == EPIPE) break; die("merge-recursive: %s", strerror(errno)); } else if (!ret) { die("merge-recursive: disk full?"); } size -= ret; buf += ret; } } static int make_room_for_path(const char *path) { int status; const char *msg = "failed to create path '%s'%s"; status = mkdir_p(path, 0777); if (status) { if (status == -3) { /* something else exists */ error(msg, path, ": perhaps a D/F conflict?"); return -1; } die(msg, 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(const unsigned char *sha, unsigned mode, const char *path, int update_cache, int update_wd) { if (index_only) update_wd = 0; if (update_wd) { enum object_type type; void *buf; unsigned long size; if (S_ISGITLINK(mode)) die("cannot read object %s '%s': It is a submodule!", sha1_to_hex(sha), path); 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 (make_room_for_path(path) < 0) { update_wd = 0; 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("failed to open %s: %s", path, strerror(errno)); flush_buffer(fd, buf, size); close(fd); } else if (S_ISLNK(mode)) { char *lnk = xmemdupz(buf, size); mkdir_p(path, 0777); unlink(path); symlink(lnk, path); free(lnk); } else die("do not know what to do with %06o %s '%s'", mode, sha1_to_hex(sha), path); } update_index: if (update_cache) add_cacheinfo(mode, sha, path, 0, update_wd, ADD_CACHE_OK_TO_ADD); } static void update_file(int clean, const unsigned char *sha, unsigned mode, const char *path) { update_file_flags(sha, mode, path, index_only || clean, !index_only); } /* Low level file merging, update and removal */ struct merge_file_info { unsigned char sha[20]; unsigned mode; unsigned clean:1, merge:1; }; static void fill_mm(const unsigned char *sha1, mmfile_t *mm) { unsigned long size; enum object_type type; if (!hashcmp(sha1, null_sha1)) { mm->ptr = xstrdup(""); mm->size = 0; return; } mm->ptr = read_sha1_file(sha1, &type, &size); if (!mm->ptr || type != OBJ_BLOB) die("unable to read blob object %s", sha1_to_hex(sha1)); mm->size = size; } /* * Customizable low-level merge drivers support. */ struct ll_merge_driver; typedef int (*ll_merge_fn)(const struct ll_merge_driver *, const char *path, mmfile_t *orig, mmfile_t *src1, const char *name1, mmfile_t *src2, const char *name2, mmbuffer_t *result); struct ll_merge_driver { const char *name; const char *description; ll_merge_fn fn; const char *recursive; struct ll_merge_driver *next; char *cmdline; }; /* * Built-in low-levels */ static int ll_binary_merge(const struct ll_merge_driver *drv_unused, const char *path_unused, mmfile_t *orig, mmfile_t *src1, const char *name1, mmfile_t *src2, const char *name2, mmbuffer_t *result) { /* * The tentative merge result is "ours" for the final round, * or common ancestor for an internal merge. Still return * "conflicted merge" status. */ mmfile_t *stolen = index_only ? orig : src1; result->ptr = stolen->ptr; result->size = stolen->size; stolen->ptr = NULL; return 1; } static int ll_xdl_merge(const struct ll_merge_driver *drv_unused, const char *path_unused, mmfile_t *orig, mmfile_t *src1, const char *name1, mmfile_t *src2, const char *name2, mmbuffer_t *result) { xpparam_t xpp; if (buffer_is_binary(orig->ptr, orig->size) || buffer_is_binary(src1->ptr, src1->size) || buffer_is_binary(src2->ptr, src2->size)) { warning("Cannot merge binary files: %s vs. %s\n", name1, name2); return ll_binary_merge(drv_unused, path_unused, orig, src1, name1, src2, name2, result); } memset(&xpp, 0, sizeof(xpp)); return xdl_merge(orig, src1, name1, src2, name2, &xpp, XDL_MERGE_ZEALOUS, result); } static int ll_union_merge(const struct ll_merge_driver *drv_unused, const char *path_unused, mmfile_t *orig, mmfile_t *src1, const char *name1, mmfile_t *src2, const char *name2, mmbuffer_t *result) { char *src, *dst; long size; const int marker_size = 7; int status = ll_xdl_merge(drv_unused, path_unused, orig, src1, NULL, src2, NULL, result); if (status <= 0) return status; size = result->size; src = dst = result->ptr; while (size) { char ch; if ((marker_size < size) && (*src == '<' || *src == '=' || *src == '>')) { int i; ch = *src; for (i = 0; i < marker_size; i++) if (src[i] != ch) goto not_a_marker; if (src[marker_size] != '\n') goto not_a_marker; src += marker_size + 1; size -= marker_size + 1; continue; } not_a_marker: do { ch = *src++; *dst++ = ch; size--; } while (ch != '\n' && size); } result->size = dst - result->ptr; return 0; } #define LL_BINARY_MERGE 0 #define LL_TEXT_MERGE 1 #define LL_UNION_MERGE 2 static struct ll_merge_driver ll_merge_drv[] = { { "binary", "built-in binary merge", ll_binary_merge }, { "text", "built-in 3-way text merge", ll_xdl_merge }, { "union", "built-in union merge", ll_union_merge }, }; static void create_temp(mmfile_t *src, char *path) { int fd; strcpy(path, ".merge_file_XXXXXX"); fd = xmkstemp(path); if (write_in_full(fd, src->ptr, src->size) != src->size) die("unable to write temp-file"); close(fd); } /* * User defined low-level merge driver support. */ static int ll_ext_merge(const struct ll_merge_driver *fn, const char *path, mmfile_t *orig, mmfile_t *src1, const char *name1, mmfile_t *src2, const char *name2, mmbuffer_t *result) { char temp[3][50]; char cmdbuf[2048]; struct interp table[] = { { "%O" }, { "%A" }, { "%B" }, }; struct child_process child; const char *args[20]; int status, fd, i; struct stat st; if (fn->cmdline == NULL) die("custom merge driver %s lacks command line.", fn->name); result->ptr = NULL; result->size = 0; create_temp(orig, temp[0]); create_temp(src1, temp[1]); create_temp(src2, temp[2]); interp_set_entry(table, 0, temp[0]); interp_set_entry(table, 1, temp[1]); interp_set_entry(table, 2, temp[2]); output(1, "merging %s using %s", path, fn->description ? fn->description : fn->name); interpolate(cmdbuf, sizeof(cmdbuf), fn->cmdline, table, 3); memset(&child, 0, sizeof(child)); child.argv = args; args[0] = "sh"; args[1] = "-c"; args[2] = cmdbuf; args[3] = NULL; status = run_command(&child); if (status < -ERR_RUN_COMMAND_FORK) ; /* failure in run-command */ else status = -status; fd = open(temp[1], O_RDONLY); if (fd < 0) goto bad; if (fstat(fd, &st)) goto close_bad; result->size = st.st_size; result->ptr = xmalloc(result->size + 1); if (read_in_full(fd, result->ptr, result->size) != result->size) { free(result->ptr); result->ptr = NULL; result->size = 0; } close_bad: close(fd); bad: for (i = 0; i < 3; i++) unlink(temp[i]); return status; } /* * merge.default and merge.driver configuration items */ static struct ll_merge_driver *ll_user_merge, **ll_user_merge_tail; static const char *default_ll_merge; static int read_merge_config(const char *var, const char *value) { struct ll_merge_driver *fn; const char *ep, *name; int namelen; if (!strcmp(var, "merge.default")) { if (!value) return config_error_nonbool(var); default_ll_merge = strdup(value); return 0; } /* * We are not interested in anything but "merge..variable"; * especially, we do not want to look at variables such as * "merge.summary", "merge.tool", and "merge.verbosity". */ if (prefixcmp(var, "merge.") || (ep = strrchr(var, '.')) == var + 5) return 0; /* * Find existing one as we might be processing merge..var2 * after seeing merge..var1. */ name = var + 6; namelen = ep - name; for (fn = ll_user_merge; fn; fn = fn->next) if (!strncmp(fn->name, name, namelen) && !fn->name[namelen]) break; if (!fn) { fn = xcalloc(1, sizeof(struct ll_merge_driver)); fn->name = xmemdupz(name, namelen); fn->fn = ll_ext_merge; *ll_user_merge_tail = fn; ll_user_merge_tail = &(fn->next); } ep++; if (!strcmp("name", ep)) { if (!value) return config_error_nonbool(var); fn->description = strdup(value); return 0; } if (!strcmp("driver", ep)) { if (!value) return config_error_nonbool(var); /* * merge..driver specifies the command line: * * command-line * * The command-line will be interpolated with the following * tokens and is given to the shell: * * %O - temporary file name for the merge base. * %A - temporary file name for our version. * %B - temporary file name for the other branches' version. * * The external merge driver should write the results in the * file named by %A, and signal that it has done with zero exit * status. */ fn->cmdline = strdup(value); return 0; } if (!strcmp("recursive", ep)) { if (!value) return config_error_nonbool(var); fn->recursive = strdup(value); return 0; } return 0; } static void initialize_ll_merge(void) { if (ll_user_merge_tail) return; ll_user_merge_tail = &ll_user_merge; git_config(read_merge_config); } static const struct ll_merge_driver *find_ll_merge_driver(const char *merge_attr) { struct ll_merge_driver *fn; const char *name; int i; initialize_ll_merge(); if (ATTR_TRUE(merge_attr)) return &ll_merge_drv[LL_TEXT_MERGE]; else if (ATTR_FALSE(merge_attr)) return &ll_merge_drv[LL_BINARY_MERGE]; else if (ATTR_UNSET(merge_attr)) { if (!default_ll_merge) return &ll_merge_drv[LL_TEXT_MERGE]; else name = default_ll_merge; } else name = merge_attr; for (fn = ll_user_merge; fn; fn = fn->next) if (!strcmp(fn->name, name)) return fn; for (i = 0; i < ARRAY_SIZE(ll_merge_drv); i++) if (!strcmp(ll_merge_drv[i].name, name)) return &ll_merge_drv[i]; /* default to the 3-way */ return &ll_merge_drv[LL_TEXT_MERGE]; } static const char *git_path_check_merge(const char *path) { static struct git_attr_check attr_merge_check; if (!attr_merge_check.attr) attr_merge_check.attr = git_attr("merge", 5); if (git_checkattr(path, 1, &attr_merge_check)) return NULL; return attr_merge_check.value; } static int ll_merge(mmbuffer_t *result_buf, struct diff_filespec *o, struct diff_filespec *a, struct diff_filespec *b, const char *branch1, const char *branch2) { mmfile_t orig, src1, src2; char *name1, *name2; int merge_status; const char *ll_driver_name; const struct ll_merge_driver *driver; name1 = xstrdup(mkpath("%s:%s", branch1, a->path)); name2 = xstrdup(mkpath("%s:%s", branch2, b->path)); fill_mm(o->sha1, &orig); fill_mm(a->sha1, &src1); fill_mm(b->sha1, &src2); ll_driver_name = git_path_check_merge(a->path); driver = find_ll_merge_driver(ll_driver_name); if (index_only && driver->recursive) driver = find_ll_merge_driver(driver->recursive); merge_status = driver->fn(driver, a->path, &orig, &src1, name1, &src2, name2, result_buf); free(name1); free(name2); free(orig.ptr); free(src1.ptr); free(src2.ptr); return merge_status; } static struct merge_file_info merge_file(struct diff_filespec *o, struct diff_filespec *a, struct diff_filespec *b, const char *branch1, const char *branch2) { struct merge_file_info result; result.merge = 0; result.clean = 1; if ((S_IFMT & a->mode) != (S_IFMT & b->mode)) { result.clean = 0; if (S_ISREG(a->mode)) { result.mode = a->mode; hashcpy(result.sha, a->sha1); } else { result.mode = b->mode; hashcpy(result.sha, b->sha1); } } else { if (!sha_eq(a->sha1, o->sha1) && !sha_eq(b->sha1, o->sha1)) result.merge = 1; /* * Merge modes */ if (a->mode == b->mode || a->mode == o->mode) result.mode = b->mode; else { result.mode = a->mode; if (b->mode != o->mode) { result.clean = 0; result.merge = 1; } } if (sha_eq(a->sha1, b->sha1) || sha_eq(a->sha1, o->sha1)) hashcpy(result.sha, b->sha1); else if (sha_eq(b->sha1, o->sha1)) hashcpy(result.sha, a->sha1); else if (S_ISREG(a->mode)) { mmbuffer_t result_buf; int merge_status; merge_status = ll_merge(&result_buf, o, 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 = 0; hashcpy(result.sha, a->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_rename(struct rename *ren1, const char *branch1, struct rename *ren2, const char *branch2) { char *del[2]; int delp = 0; const char *ren1_dst = ren1->pair->two->path; const char *ren2_dst = ren2->pair->two->path; const char *dst_name1 = ren1_dst; const char *dst_name2 = ren2_dst; if (path_list_has_path(¤t_directory_set, ren1_dst)) { dst_name1 = del[delp++] = unique_path(ren1_dst, branch1); output(1, "%s is a directory in %s added as %s instead", ren1_dst, branch2, dst_name1); remove_file(0, ren1_dst, 0); } if (path_list_has_path(¤t_directory_set, ren2_dst)) { dst_name2 = del[delp++] = unique_path(ren2_dst, branch2); output(1, "%s is a directory in %s added as %s instead", ren2_dst, branch1, dst_name2); remove_file(0, ren2_dst, 0); } if (index_only) { remove_file_from_cache(dst_name1); remove_file_from_cache(dst_name2); /* * Uncomment to leave the conflicting names in the resulting tree * * update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, dst_name1); * update_file(0, ren2->pair->two->sha1, ren2->pair->two->mode, dst_name2); */ } else { update_stages(dst_name1, NULL, ren1->pair->two, NULL, 1); update_stages(dst_name2, NULL, NULL, ren2->pair->two, 1); } while (delp--) free(del[delp]); } static void conflict_rename_dir(struct rename *ren1, const char *branch1) { char *new_path = unique_path(ren1->pair->two->path, branch1); output(1, "Renamed %s to %s instead", ren1->pair->one->path, new_path); remove_file(0, ren1->pair->two->path, 0); update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path); free(new_path); } static void conflict_rename_rename_2(struct rename *ren1, const char *branch1, struct rename *ren2, const char *branch2) { char *new_path1 = unique_path(ren1->pair->two->path, branch1); char *new_path2 = unique_path(ren2->pair->two->path, branch2); output(1, "Renamed %s to %s and %s to %s instead", ren1->pair->one->path, new_path1, ren2->pair->one->path, new_path2); remove_file(0, ren1->pair->two->path, 0); update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path1); update_file(0, ren2->pair->two->sha1, ren2->pair->two->mode, new_path2); free(new_path2); free(new_path1); } static int process_renames(struct path_list *a_renames, struct path_list *b_renames, const char *a_branch, const char *b_branch) { int clean_merge = 1, i, j; struct path_list a_by_dst = {NULL, 0, 0, 0}, b_by_dst = {NULL, 0, 0, 0}; const struct rename *sre; for (i = 0; i < a_renames->nr; i++) { sre = a_renames->items[i].util; path_list_insert(sre->pair->two->path, &a_by_dst)->util = sre->dst_entry; } for (i = 0; i < b_renames->nr; i++) { sre = b_renames->items[i].util; path_list_insert(sre->pair->two->path, &b_by_dst)->util = sre->dst_entry; } for (i = 0, j = 0; i < a_renames->nr || j < b_renames->nr;) { int compare; char *src; struct path_list *renames1, *renames2, *renames2Dst; struct rename *ren1 = NULL, *ren2 = NULL; const char *branch1, *branch2; const char *ren1_src, *ren1_dst; if (i >= a_renames->nr) { compare = 1; ren2 = b_renames->items[j++].util; } else if (j >= b_renames->nr) { compare = -1; ren1 = a_renames->items[i++].util; } else { compare = strcmp(a_renames->items[i].path, b_renames->items[j].path); if (compare <= 0) ren1 = a_renames->items[i++].util; if (compare >= 0) ren2 = b_renames->items[j++].util; } /* TODO: refactor, so that 1/2 are not needed */ if (ren1) { renames1 = a_renames; renames2 = b_renames; renames2Dst = &b_by_dst; branch1 = a_branch; branch2 = b_branch; } else { struct rename *tmp; renames1 = b_renames; renames2 = a_renames; renames2Dst = &a_by_dst; branch1 = b_branch; branch2 = a_branch; tmp = ren2; ren2 = ren1; ren1 = tmp; } src = ren1->pair->one->path; ren1->dst_entry->processed = 1; ren1->src_entry->processed = 1; if (ren1->processed) continue; ren1->processed = 1; ren1_src = ren1->pair->one->path; ren1_dst = ren1->pair->two->path; if (ren2) { const char *ren2_src = ren2->pair->one->path; const char *ren2_dst = ren2->pair->two->path; /* Renamed in 1 and renamed in 2 */ if (strcmp(ren1_src, ren2_src) != 0) die("ren1.src != ren2.src"); ren2->dst_entry->processed = 1; ren2->processed = 1; if (strcmp(ren1_dst, ren2_dst) != 0) { clean_merge = 0; output(1, "CONFLICT (rename/rename): " "Rename \"%s\"->\"%s\" in branch \"%s\" " "rename \"%s\"->\"%s\" in \"%s\"%s", src, ren1_dst, branch1, src, ren2_dst, branch2, index_only ? " (left unresolved)": ""); if (index_only) { remove_file_from_cache(src); update_file(0, ren1->pair->one->sha1, ren1->pair->one->mode, src); } conflict_rename_rename(ren1, branch1, ren2, branch2); } else { struct merge_file_info mfi; remove_file(1, ren1_src, 1); mfi = merge_file(ren1->pair->one, ren1->pair->two, ren2->pair->two, branch1, branch2); if (mfi.merge || !mfi.clean) output(1, "Renamed %s->%s", src, ren1_dst); if (mfi.merge) output(2, "Auto-merged %s", ren1_dst); if (!mfi.clean) { output(1, "CONFLICT (content): merge conflict in %s", ren1_dst); clean_merge = 0; if (!index_only) update_stages(ren1_dst, ren1->pair->one, ren1->pair->two, ren2->pair->two, 1 /* clear */); } update_file(mfi.clean, mfi.sha, mfi.mode, ren1_dst); } } else { /* Renamed in 1, maybe changed in 2 */ struct path_list_item *item; /* we only use sha1 and mode of these */ struct diff_filespec src_other, dst_other; int try_merge, stage = a_renames == renames1 ? 3: 2; remove_file(1, ren1_src, index_only || stage == 3); hashcpy(src_other.sha1, ren1->src_entry->stages[stage].sha); src_other.mode = ren1->src_entry->stages[stage].mode; hashcpy(dst_other.sha1, ren1->dst_entry->stages[stage].sha); dst_other.mode = ren1->dst_entry->stages[stage].mode; try_merge = 0; if (path_list_has_path(¤t_directory_set, ren1_dst)) { clean_merge = 0; output(1, "CONFLICT (rename/directory): Renamed %s->%s in %s " " directory %s added in %s", ren1_src, ren1_dst, branch1, ren1_dst, branch2); conflict_rename_dir(ren1, branch1); } else if (sha_eq(src_other.sha1, null_sha1)) { clean_merge = 0; output(1, "CONFLICT (rename/delete): Renamed %s->%s in %s " "and deleted in %s", ren1_src, ren1_dst, branch1, branch2); update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, ren1_dst); } else if (!sha_eq(dst_other.sha1, null_sha1)) { const char *new_path; clean_merge = 0; try_merge = 1; output(1, "CONFLICT (rename/add): Renamed %s->%s in %s. " "%s added in %s", ren1_src, ren1_dst, branch1, ren1_dst, branch2); new_path = unique_path(ren1_dst, branch2); output(1, "Added as %s instead", new_path); update_file(0, dst_other.sha1, dst_other.mode, new_path); } else if ((item = path_list_lookup(ren1_dst, renames2Dst))) { ren2 = item->util; clean_merge = 0; ren2->processed = 1; output(1, "CONFLICT (rename/rename): Renamed %s->%s in %s. " "Renamed %s->%s in %s", ren1_src, ren1_dst, branch1, ren2->pair->one->path, ren2->pair->two->path, branch2); conflict_rename_rename_2(ren1, branch1, ren2, branch2); } else try_merge = 1; if (try_merge) { struct diff_filespec *o, *a, *b; struct merge_file_info mfi; src_other.path = (char *)ren1_src; o = ren1->pair->one; if (a_renames == renames1) { a = ren1->pair->two; b = &src_other; } else { b = ren1->pair->two; a = &src_other; } mfi = merge_file(o, a, b, a_branch, b_branch); if (mfi.clean && sha_eq(mfi.sha, ren1->pair->two->sha1) && mfi.mode == ren1->pair->two->mode) /* * This messaged is part of * t6022 test. If you change * it update the test too. */ output(3, "Skipped %s (merged same as existing)", ren1_dst); else { if (mfi.merge || !mfi.clean) output(1, "Renamed %s => %s", ren1_src, ren1_dst); if (mfi.merge) output(2, "Auto-merged %s", ren1_dst); if (!mfi.clean) { output(1, "CONFLICT (rename/modify): Merge conflict in %s", ren1_dst); clean_merge = 0; if (!index_only) update_stages(ren1_dst, o, a, b, 1); } update_file(mfi.clean, mfi.sha, mfi.mode, ren1_dst); } } } } path_list_clear(&a_by_dst, 0); path_list_clear(&b_by_dst, 0); return clean_merge; } static unsigned char *stage_sha(const unsigned char *sha, unsigned mode) { return (is_null_sha1(sha) || mode == 0) ? NULL: (unsigned char *)sha; } /* Per entry merge function */ static int process_entry(const char *path, struct stage_data *entry, const char *branch1, const char *branch2) { /* printf("processing entry, clean cache: %s\n", index_only ? "yes": "no"); print_index_entry("\tpath: ", entry); */ int clean_merge = 1; unsigned o_mode = entry->stages[1].mode; unsigned a_mode = entry->stages[2].mode; unsigned b_mode = entry->stages[3].mode; unsigned char *o_sha = stage_sha(entry->stages[1].sha, o_mode); unsigned char *a_sha = stage_sha(entry->stages[2].sha, a_mode); unsigned char *b_sha = stage_sha(entry->stages[3].sha, b_mode); if (o_sha && (!a_sha || !b_sha)) { /* Case A: Deleted in one */ if ((!a_sha && !b_sha) || (sha_eq(a_sha, o_sha) && !b_sha) || (!a_sha && sha_eq(b_sha, o_sha))) { /* Deleted in both or deleted in one and * unchanged in the other */ if (a_sha) output(2, "Removed %s", path); /* do not touch working file if it did not exist */ remove_file(1, path, !a_sha); } else { /* Deleted in one and changed in the other */ clean_merge = 0; if (!a_sha) { output(1, "CONFLICT (delete/modify): %s deleted in %s " "and modified in %s. Version %s of %s left in tree.", path, branch1, branch2, branch2, path); update_file(0, b_sha, b_mode, path); } else { output(1, "CONFLICT (delete/modify): %s deleted in %s " "and modified in %s. Version %s of %s left in tree.", path, branch2, branch1, branch1, path); update_file(0, a_sha, a_mode, path); } } } else if ((!o_sha && a_sha && !b_sha) || (!o_sha && !a_sha && b_sha)) { /* Case B: Added in one. */ const char *add_branch; const char *other_branch; unsigned mode; const unsigned char *sha; const char *conf; if (a_sha) { add_branch = branch1; other_branch = branch2; mode = a_mode; sha = a_sha; conf = "file/directory"; } else { add_branch = branch2; other_branch = branch1; mode = b_mode; sha = b_sha; conf = "directory/file"; } if (path_list_has_path(¤t_directory_set, path)) { const char *new_path = unique_path(path, add_branch); clean_merge = 0; output(1, "CONFLICT (%s): There is a directory with name %s in %s. " "Added %s as %s", conf, path, other_branch, path, new_path); remove_file(0, path, 0); update_file(0, sha, mode, new_path); } else { output(2, "Added %s", path); update_file(1, sha, mode, path); } } else if (a_sha && b_sha) { /* Case C: Added in both (check for same permissions) and */ /* case D: Modified in both, but differently. */ const char *reason = "content"; struct merge_file_info mfi; struct diff_filespec o, a, b; if (!o_sha) { reason = "add/add"; o_sha = (unsigned char *)null_sha1; } output(2, "Auto-merged %s", path); o.path = a.path = b.path = (char *)path; hashcpy(o.sha1, o_sha); o.mode = o_mode; hashcpy(a.sha1, a_sha); a.mode = a_mode; hashcpy(b.sha1, b_sha); b.mode = b_mode; mfi = merge_file(&o, &a, &b, branch1, branch2); clean_merge = mfi.clean; if (mfi.clean) update_file(1, mfi.sha, mfi.mode, path); else if (S_ISGITLINK(mfi.mode)) output(1, "CONFLICT (submodule): Merge conflict in %s " "- needs %s", path, sha1_to_hex(b.sha1)); else { output(1, "CONFLICT (%s): Merge conflict in %s", reason, path); if (index_only) update_file(0, mfi.sha, mfi.mode, path); else update_file_flags(mfi.sha, mfi.mode, path, 0 /* update_cache */, 1 /* update_working_directory */); } } else if (!o_sha && !a_sha && !b_sha) { /* * this entry was deleted altogether. a_mode == 0 means * we had that path and want to actively remove it. */ remove_file(1, path, !a_mode); } else die("Fatal merge failure, shouldn't happen."); return clean_merge; } static int merge_trees(struct tree *head, struct tree *merge, struct tree *common, const char *branch1, const char *branch2, struct tree **result) { int code, clean; if (subtree_merge) { merge = shift_tree_object(head, merge); common = shift_tree_object(head, common); } if (sha_eq(common->object.sha1, merge->object.sha1)) { output(0, "Already uptodate!"); *result = head; return 1; } code = git_merge_trees(index_only, common, head, merge); if (code != 0) die("merging of trees %s and %s failed", sha1_to_hex(head->object.sha1), sha1_to_hex(merge->object.sha1)); if (unmerged_index()) { struct path_list *entries, *re_head, *re_merge; int i; path_list_clear(¤t_file_set, 1); path_list_clear(¤t_directory_set, 1); get_files_dirs(head); get_files_dirs(merge); entries = get_unmerged(); re_head = get_renames(head, common, head, merge, entries); re_merge = get_renames(merge, common, head, merge, entries); clean = process_renames(re_head, re_merge, branch1, branch2); for (i = 0; i < entries->nr; i++) { const char *path = entries->items[i].path; struct stage_data *e = entries->items[i].util; if (!e->processed && !process_entry(path, e, branch1, branch2)) clean = 0; } path_list_clear(re_merge, 0); path_list_clear(re_head, 0); path_list_clear(entries, 1); } else clean = 1; if (index_only) *result = git_write_tree(); return clean; } static struct commit_list *reverse_commit_list(struct commit_list *list) { struct commit_list *next = NULL, *current, *backup; for (current = list; current; current = backup) { backup = current->next; current->next = next; next = current; } return next; } /* * Merge the commits h1 and h2, return the resulting virtual * commit object and a flag indicating the cleanness of the merge. */ static int merge(struct commit *h1, struct commit *h2, const char *branch1, const char *branch2, struct commit_list *ca, struct commit **result) { struct commit_list *iter; struct commit *merged_common_ancestors; struct tree *mrtree = mrtree; int clean; if (show(4)) { output(4, "Merging:"); output_commit_title(h1); output_commit_title(h2); } if (!ca) { ca = get_merge_bases(h1, h2, 1); ca = reverse_commit_list(ca); } if (show(5)) { output(5, "found %u common ancestor(s):", commit_list_count(ca)); for (iter = ca; iter; iter = iter->next) output_commit_title(iter->item); } merged_common_ancestors = pop_commit(&ca); if (merged_common_ancestors == NULL) { /* if there is no common ancestor, make an empty tree */ struct tree *tree = xcalloc(1, sizeof(struct tree)); tree->object.parsed = 1; tree->object.type = OBJ_TREE; pretend_sha1_file(NULL, 0, OBJ_TREE, tree->object.sha1); merged_common_ancestors = make_virtual_commit(tree, "ancestor"); } for (iter = ca; iter; iter = iter->next) { call_depth++; /* * When the merge fails, the result contains files * with conflict markers. The cleanness flag is * ignored, it was never actually used, as result of * merge_trees has always overwritten it: the committed * "conflicts" were already resolved. */ discard_cache(); merge(merged_common_ancestors, iter->item, "Temporary merge branch 1", "Temporary merge branch 2", NULL, &merged_common_ancestors); call_depth--; if (!merged_common_ancestors) die("merge returned no commit"); } discard_cache(); if (!call_depth) { read_cache(); index_only = 0; } else index_only = 1; clean = merge_trees(h1->tree, h2->tree, merged_common_ancestors->tree, branch1, branch2, &mrtree); if (index_only) { *result = make_virtual_commit(mrtree, "merged tree"); commit_list_insert(h1, &(*result)->parents); commit_list_insert(h2, &(*result)->parents->next); } flush_output(); return clean; } static const char *better_branch_name(const char *branch) { static char githead_env[8 + 40 + 1]; char *name; if (strlen(branch) != 40) return branch; sprintf(githead_env, "GITHEAD_%s", branch); name = getenv(githead_env); return name ? name : branch; } static struct commit *get_ref(const char *ref) { unsigned char sha1[20]; struct object *object; if (get_sha1(ref, sha1)) die("Could not resolve ref '%s'", ref); object = deref_tag(parse_object(sha1), ref, strlen(ref)); if (object->type == OBJ_TREE) return make_virtual_commit((struct tree*)object, better_branch_name(ref)); if (object->type != OBJ_COMMIT) return NULL; if (parse_commit((struct commit *)object)) die("Could not parse commit '%s'", sha1_to_hex(object->sha1)); return (struct commit *)object; } static int merge_config(const char *var, const char *value) { if (!strcasecmp(var, "merge.verbosity")) { verbosity = git_config_int(var, value); return 0; } if (!strcasecmp(var, "diff.renamelimit")) { rename_limit = git_config_int(var, value); return 0; } return git_default_config(var, value); } int main(int argc, char *argv[]) { static const char *bases[20]; static unsigned bases_count = 0; int i, clean; const char *branch1, *branch2; struct commit *result, *h1, *h2; struct commit_list *ca = NULL; struct lock_file *lock = xcalloc(1, sizeof(struct lock_file)); int index_fd; if (argv[0]) { int namelen = strlen(argv[0]); if (8 < namelen && !strcmp(argv[0] + namelen - 8, "-subtree")) subtree_merge = 1; } git_config(merge_config); if (getenv("GIT_MERGE_VERBOSITY")) verbosity = strtol(getenv("GIT_MERGE_VERBOSITY"), NULL, 10); if (argc < 4) die("Usage: %s ... -- ...\n", argv[0]); for (i = 1; i < argc; ++i) { if (!strcmp(argv[i], "--")) break; if (bases_count < sizeof(bases)/sizeof(*bases)) bases[bases_count++] = argv[i]; } if (argc - i != 3) /* "--" "" "" */ die("Not handling anything other than two heads merge."); if (verbosity >= 5) buffer_output = 0; branch1 = argv[++i]; branch2 = argv[++i]; h1 = get_ref(branch1); h2 = get_ref(branch2); branch1 = better_branch_name(branch1); branch2 = better_branch_name(branch2); if (show(3)) printf("Merging %s with %s\n", branch1, branch2); index_fd = hold_locked_index(lock, 1); for (i = 0; i < bases_count; i++) { struct commit *ancestor = get_ref(bases[i]); ca = commit_list_insert(ancestor, &ca); } clean = merge(h1, h2, branch1, branch2, ca, &result); if (active_cache_changed && (write_cache(index_fd, active_cache, active_nr) || commit_locked_index(lock))) die ("unable to write %s", get_index_file()); return clean ? 0: 1; }