]> git.ipfire.org Git - thirdparty/git.git/blobdiff - merge-recursive.c
merge: add merge.renames config setting
[thirdparty/git.git] / merge-recursive.c
index 9c05eb7f700eed0dc3e20a4c22f3a60e0aa21488..e98404964da7af9496fadf78b349bcf3c7a97832 100644 (file)
@@ -316,7 +316,7 @@ static int add_cacheinfo(struct merge_options *o,
 
        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);
+               return err(o, _("add_cacheinfo failed for path '%s'; merge aborting."), path);
 
        ret = add_cache_entry(ce, options);
        if (refresh) {
@@ -324,7 +324,7 @@ static int add_cacheinfo(struct merge_options *o,
 
                nce = refresh_cache_entry(ce, CE_MATCH_REFRESH | CE_MATCH_IGNORE_MISSING);
                if (!nce)
-                       return err(o, _("addinfo_cache failed for path '%s'"), path);
+                       return err(o, _("add_cacheinfo failed to refresh for path '%s'; merge aborting."), path);
                if (nce != ce)
                        ret = add_cache_entry(nce, options);
        }
@@ -344,6 +344,7 @@ static int git_merge_trees(struct merge_options *o,
 {
        int rc;
        struct tree_desc t[3];
+       struct index_state tmp_index = { NULL };
 
        memset(&o->unpack_opts, 0, sizeof(o->unpack_opts));
        if (o->call_depth)
@@ -354,7 +355,7 @@ static int git_merge_trees(struct merge_options *o,
        o->unpack_opts.head_idx = 2;
        o->unpack_opts.fn = threeway_merge;
        o->unpack_opts.src_index = &the_index;
-       o->unpack_opts.dst_index = &the_index;
+       o->unpack_opts.dst_index = &tmp_index;
        setup_unpack_trees_porcelain(&o->unpack_opts, "merge");
 
        init_tree_desc_from_tree(t+0, common);
@@ -362,13 +363,18 @@ static int git_merge_trees(struct merge_options *o,
        init_tree_desc_from_tree(t+2, merge);
 
        rc = unpack_trees(3, t, &o->unpack_opts);
+       cache_tree_free(&active_cache_tree);
+
        /*
-        * unpack_trees NULLifies src_index, but it's used in verify_uptodate,
-        * so set to the new index which will usually have modification
-        * timestamp info copied over.
+        * Update the_index to match the new results, AFTER saving a copy
+        * in o->orig_index.  Update src_index to point to the saved copy.
+        * (verify_uptodate() checks src_index, and the original index is
+        * the one that had the necessary modification timestamps.)
         */
-       o->unpack_opts.src_index = &the_index;
-       cache_tree_free(&active_cache_tree);
+       o->orig_index = the_index;
+       the_index = tmp_index;
+       o->unpack_opts.src_index = &o->orig_index;
+
        return rc;
 }
 
@@ -427,14 +433,14 @@ static void get_files_dirs(struct merge_options *o, struct tree *tree)
        read_tree_recursive(tree, "", 0, 0, &match_all, save_files_dirs, o);
 }
 
-static int get_tree_entry_if_blob(struct tree *tree,
+static int get_tree_entry_if_blob(const struct object_id *tree,
                                  const char *path,
                                  struct object_id *hashy,
                                  unsigned int *mode_o)
 {
        int ret;
 
-       ret = get_tree_entry(&tree->object.oid, path, hashy, mode_o);
+       ret = get_tree_entry(tree, path, hashy, mode_o);
        if (S_ISDIR(*mode_o)) {
                oidcpy(hashy, &null_oid);
                *mode_o = 0;
@@ -452,11 +458,11 @@ static struct stage_data *insert_stage_data(const char *path,
 {
        struct string_list_item *item;
        struct stage_data *e = xcalloc(1, sizeof(struct stage_data));
-       get_tree_entry_if_blob(o, path,
+       get_tree_entry_if_blob(&o->object.oid, path,
                               &e->stages[1].oid, &e->stages[1].mode);
-       get_tree_entry_if_blob(a, path,
+       get_tree_entry_if_blob(&a->object.oid, path,
                               &e->stages[2].oid, &e->stages[2].mode);
-       get_tree_entry_if_blob(b, path,
+       get_tree_entry_if_blob(&b->object.oid, path,
                               &e->stages[3].oid, &e->stages[3].mode);
        item = string_list_insert(entries, path);
        item->util = e;
@@ -773,31 +779,78 @@ static int dir_in_way(const char *path, int check_working_copy, int empty_ok)
                !(empty_ok && is_empty_dir(path));
 }
 
-static int was_tracked(const char *path)
+/*
+ * Returns whether path was tracked in the index before the merge started,
+ * and its oid and mode match the specified values
+ */
+static int was_tracked_and_matches(struct merge_options *o, const char *path,
+                                  const struct object_id *oid, unsigned mode)
 {
-       int pos = cache_name_pos(path, strlen(path));
+       int pos = index_name_pos(&o->orig_index, path, strlen(path));
+       struct cache_entry *ce;
+
+       if (0 > pos)
+               /* we were not tracking this path before the merge */
+               return 0;
+
+       /* See if the file we were tracking before matches */
+       ce = o->orig_index.cache[pos];
+       return (oid_eq(&ce->oid, oid) && ce->ce_mode == mode);
+}
+
+/*
+ * Returns whether path was tracked in the index before the merge started
+ */
+static int was_tracked(struct merge_options *o, const char *path)
+{
+       int pos = index_name_pos(&o->orig_index, path, strlen(path));
 
        if (0 <= pos)
-               /* we have been tracking this path */
+               /* we were tracking this path before the merge */
                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);
+       /*
+        * This may look like it can be simplified to:
+        *   return !was_tracked(o, path) && file_exists(path)
+        * but it can't.  This function needs to know whether path was in
+        * the working tree due to EITHER having been tracked in the index
+        * before the merge OR having been put into the working copy and
+        * index by unpack_trees().  Due to that either-or requirement, we
+        * check the current index instead of the original one.
+        *
+        * Note that we do not need to worry about merge-recursive itself
+        * updating the index after unpack_trees() and before calling this
+        * function, because we strictly require all code paths in
+        * merge-recursive to update the working tree first and the index
+        * second.  Doing otherwise would break
+        * update_file()/would_lose_untracked(); see every comment in this
+        * file which mentions "update_stages".
+        */
+       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 was_dirty(struct merge_options *o, const char *path)
@@ -805,12 +858,12 @@ static int was_dirty(struct merge_options *o, const char *path)
        struct cache_entry *ce;
        int dirty = 1;
 
-       if (o->call_depth || !was_tracked(path))
+       if (o->call_depth || !was_tracked(o, path))
                return !dirty;
 
-       ce = cache_file_exists(path, strlen(path), ignore_case);
-       dirty = (ce->ce_stat_data.sd_mtime.sec > 0 &&
-                verify_uptodate(ce, &o->unpack_opts) != 0);
+       ce = index_file_exists(o->unpack_opts.src_index,
+                              path, strlen(path), ignore_case);
+       dirty = verify_uptodate(ce, &o->unpack_opts) != 0;
        return dirty;
 }
 
@@ -942,7 +995,9 @@ static int update_file_flags(struct merge_options *o,
        }
  update_index:
        if (!ret && update_cache)
-               add_cacheinfo(o, mode, oid, path, 0, update_wd, ADD_CACHE_OK_TO_ADD);
+               if (add_cacheinfo(o, mode, oid, path, 0, update_wd,
+                                 ADD_CACHE_OK_TO_ADD))
+                       return -1;
        return ret;
 }
 
@@ -1027,12 +1082,13 @@ static int merge_3way(struct merge_options *o,
 }
 
 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)
+                       const struct diff_filespec *one,
+                       const struct diff_filespec *a,
+                       const struct diff_filespec *b,
+                       const char *filename,
+                       const char *branch1,
+                       const char *branch2,
+                       struct merge_file_info *result)
 {
        result->merge = 0;
        result->clean = 1;
@@ -1112,18 +1168,22 @@ static int merge_file_1(struct merge_options *o,
                        die("BUG: unsupported object type in the tree");
        }
 
+       if (result->merge)
+               output(o, 2, _("Auto-merging %s"), filename);
+
        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)
+                                     const struct diff_filespec *one,
+                                     const struct diff_filespec *a,
+                                     const struct diff_filespec *b,
+                                     const char *target_filename,
+                                     const char *branch1,
+                                     const char *filename1,
+                                     const char *branch2,
+                                     const char *filename2,
+                                     struct merge_file_info *mfi)
 {
        char *side1 = NULL;
        char *side2 = NULL;
@@ -1134,22 +1194,23 @@ static int merge_file_special_markers(struct merge_options *o,
        if (filename2)
                side2 = xstrfmt("%s:%s", branch2, filename2);
 
-       ret = merge_file_1(o, one, a, b,
+       ret = merge_file_1(o, one, a, b, target_filename,
                           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)
+                         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;
 
@@ -1160,7 +1221,7 @@ static int merge_file_one(struct merge_options *o,
        a.mode = a_mode;
        oidcpy(&b.oid, b_oid);
        b.mode = b_mode;
-       return merge_file_1(o, &one, &a, &b, branch1, branch2, mfi);
+       return merge_file_1(o, &one, &a, &b, path, branch1, branch2, mfi);
 }
 
 static int conflict_rename_dir(struct merge_options *o,
@@ -1438,6 +1499,8 @@ static int conflict_rename_rename_2to1(struct merge_options *o,
        struct diff_filespec *c1 = ci->pair1->two;
        struct diff_filespec *c2 = ci->pair2->two;
        char *path = c1->path; /* == c2->path */
+       char *path_side_1_desc;
+       char *path_side_2_desc;
        struct merge_file_info mfi_c1;
        struct merge_file_info mfi_c2;
        int ret;
@@ -1451,13 +1514,19 @@ static int conflict_rename_rename_2to1(struct merge_options *o,
        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));
 
+       path_side_1_desc = xstrfmt("%s (was %s)", path, a->path);
+       path_side_2_desc = xstrfmt("%s (was %s)", path, b->path);
        if (merge_file_special_markers(o, a, c1, &ci->ren1_other,
+                                      path_side_1_desc,
                                       o->branch1, c1->path,
                                       o->branch2, ci->ren1_other.path, &mfi_c1) ||
            merge_file_special_markers(o, b, &ci->ren2_other, c2,
+                                      path_side_2_desc,
                                       o->branch1, ci->ren2_other.path,
                                       o->branch2, c2->path, &mfi_c2))
                return -1;
+       free(path_side_1_desc);
+       free(path_side_2_desc);
 
        if (o->call_depth) {
                /*
@@ -1534,7 +1603,15 @@ static struct diff_queue_struct *get_diffpairs(struct merge_options *o,
        diff_setup(&opts);
        opts.flags.recursive = 1;
        opts.flags.rename_empty = 0;
-       opts.detect_rename = DIFF_DETECT_RENAME;
+       opts.detect_rename = merge_detect_rename(o);
+       /*
+        * We do not have logic to handle the detection of copies.  In
+        * fact, it may not even make sense to add such logic: would we
+        * really want a change to a base file to be propagated through
+        * multiple other files by a merge?
+        */
+       if (opts.detect_rename > DIFF_DETECT_RENAME)
+               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;
@@ -1861,7 +1938,7 @@ static struct hashmap *get_directory_renames(struct diff_queue_struct *pairs,
         * renames, finding out how often each directory rename pair
         * possibility occurs.
         */
-       dir_renames = xmalloc(sizeof(struct hashmap));
+       dir_renames = xmalloc(sizeof(*dir_renames));
        dir_rename_init(dir_renames);
        for (i = 0; i < pairs->nr; ++i) {
                struct string_list_item *item;
@@ -1881,7 +1958,7 @@ static struct hashmap *get_directory_renames(struct diff_queue_struct *pairs,
 
                entry = dir_rename_find_entry(dir_renames, old_dir);
                if (!entry) {
-                       entry = xmalloc(sizeof(struct dir_rename_entry));
+                       entry = xmalloc(sizeof(*entry));
                        dir_rename_entry_init(entry, old_dir);
                        hashmap_put(dir_renames, entry);
                } else {
@@ -2417,7 +2494,7 @@ static int process_renames(struct merge_options *o,
                         * add-source case).
                         */
                        remove_file(o, 1, ren1_src,
-                                   renamed_stage == 2 || !was_tracked(ren1_src));
+                                   renamed_stage == 2 || !was_tracked(o, ren1_src));
 
                        oidcpy(&src_other.oid,
                               &ren1->src_entry->stages[other_stage].oid);
@@ -2574,7 +2651,7 @@ static int handle_renames(struct merge_options *o,
        ri->head_renames = NULL;
        ri->merge_renames = NULL;
 
-       if (!o->detect_rename)
+       if (!merge_detect_rename(o))
                return 1;
 
        head_pairs = get_diffpairs(o, common, head);
@@ -2725,7 +2802,7 @@ static int handle_modify_delete(struct merge_options *o,
 
 static int merge_content(struct merge_options *o,
                         const char *path,
-                        int file_in_way,
+                        int is_dirty,
                         struct object_id *o_oid, int o_mode,
                         struct object_id *a_oid, int a_mode,
                         struct object_id *b_oid, int b_mode,
@@ -2766,27 +2843,26 @@ static int merge_content(struct merge_options *o,
                               S_ISGITLINK(pair1->two->mode)))
                        df_conflict_remains = 1;
        }
-       if (merge_file_special_markers(o, &one, &a, &b,
+       if (merge_file_special_markers(o, &one, &a, &b, path,
                                       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) {
+       /*
+        * We can skip updating the working tree file iff:
+        *   a) The merge is clean
+        *   b) The merge matches what was in HEAD (content, mode, pathname)
+        *   c) The target path is usable (i.e. not involved in D/F conflict)
+        */
+       if (mfi.clean &&
+           was_tracked_and_matches(o, path, &mfi.oid, mfi.mode) &&
+           !df_conflict_remains) {
                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).
-                */
-               if (was_tracked(path)) {
-                       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 (add_cacheinfo(o, mfi.mode, &mfi.oid, path,
+                                 0, (!o->call_depth && !is_dirty), 0))
+                       return -1;
+               return mfi.clean;
+       }
 
        if (!mfi.clean) {
                if (S_ISGITLINK(mfi.mode))
@@ -2798,7 +2874,7 @@ static int merge_content(struct merge_options *o,
                                return -1;
        }
 
-       if (df_conflict_remains || file_in_way) {
+       if (df_conflict_remains || is_dirty) {
                char *new_path;
                if (o->call_depth) {
                        remove_file_from_cache(path);
@@ -2807,7 +2883,7 @@ static int merge_content(struct merge_options *o,
                                if (update_stages(o, path, &one, &a, &b))
                                        return -1;
                        } else {
-                               int file_from_stage2 = was_tracked(path);
+                               int file_from_stage2 = was_tracked(o, path);
                                struct diff_filespec merged;
                                oidcpy(&merged.oid, &mfi.oid);
                                merged.mode = mfi.mode;
@@ -2820,6 +2896,10 @@ static int merge_content(struct merge_options *o,
 
                }
                new_path = unique_path(o, path, rename_conflict_info->branch1);
+               if (is_dirty) {
+                       output(o, 1, _("Refusing to lose dirty file at %s"),
+                              path);
+               }
                output(o, 1, _("Adding as %s instead"), new_path);
                if (update_file(o, 0, &mfi.oid, mfi.mode, new_path)) {
                        free(new_path);
@@ -2829,7 +2909,7 @@ static int merge_content(struct merge_options *o,
                mfi.clean = 0;
        } else if (update_file(o, mfi.clean, &mfi.oid, mfi.mode, path))
                return -1;
-       return mfi.clean;
+       return !is_dirty && mfi.clean;
 }
 
 static int conflict_rename_normal(struct merge_options *o,
@@ -2839,21 +2919,10 @@ static int conflict_rename_normal(struct merge_options *o,
                                  struct object_id *b_oid, unsigned int b_mode,
                                  struct rename_conflict_info *ci)
 {
-       int clean_merge;
-       int file_in_the_way = 0;
-
-       if (was_dirty(o, path)) {
-               file_in_the_way = 1;
-               output(o, 1, _("Refusing to lose dirty file at %s"), path);
-       }
-
        /* Merge the content and write it out */
-       clean_merge = merge_content(o, path, file_in_the_way,
-                                   o_oid, o_mode, a_oid, a_mode, b_oid, b_mode,
-                                   ci);
-       if (clean_merge > 0 && file_in_the_way)
-               clean_merge = 0;
-       return clean_merge;
+       return merge_content(o, path, was_dirty(o, path),
+                            o_oid, o_mode, a_oid, a_mode, b_oid, b_mode,
+                            ci);
 }
 
 /* Per entry merge function */
@@ -2976,7 +3045,8 @@ static int process_entry(struct merge_options *o,
        } 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, 0 /* file_in_way */,
+               int is_dirty = 0; /* unpack_trees would have bailed if dirty */
+               clean_merge = merge_content(o, path, is_dirty,
                                            o_oid, o_mode, a_oid, a_mode, b_oid, b_mode,
                                            NULL);
        } else if (!o_oid && !a_oid && !b_oid) {
@@ -3082,6 +3152,15 @@ cleanup:
        else
                clean = 1;
 
+       /* Free the extra index left from git_merge_trees() */
+       /*
+        * FIXME: Need to also free data allocated by
+        * setup_unpack_trees_porcelain() tucked away in o->unpack_opts.msgs,
+        * but the problem is that only half of it refers to dynamically
+        * allocated data, while the other half points at static strings.
+        */
+       discard_index(&o->orig_index);
+
        if (o->call_depth && !(*result = write_tree_from_memory(o)))
                return -1;
 
@@ -3253,9 +3332,18 @@ int merge_recursive_generic(struct merge_options *o,
 
 static void merge_recursive_config(struct merge_options *o)
 {
+       char *value = NULL;
        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);
+       if (!git_config_get_string("diff.renames", &value)) {
+               o->diff_detect_rename = git_config_rename("diff.renames", value);
+               free(value);
+       }
+       if (!git_config_get_string("merge.renames", &value)) {
+               o->merge_detect_rename = git_config_rename("merge.renames", value);
+               free(value);
+       }
        git_config(git_xmerge_config, NULL);
 }
 
@@ -3268,7 +3356,8 @@ void init_merge_options(struct merge_options *o)
        o->diff_rename_limit = -1;
        o->merge_rename_limit = -1;
        o->renormalize = 0;
-       o->detect_rename = 1;
+       o->diff_detect_rename = -1;
+       o->merge_detect_rename = -1;
        merge_recursive_config(o);
        merge_verbosity = getenv("GIT_MERGE_VERBOSITY");
        if (merge_verbosity)
@@ -3319,16 +3408,16 @@ int parse_merge_opt(struct merge_options *o, const char *s)
        else if (!strcmp(s, "no-renormalize"))
                o->renormalize = 0;
        else if (!strcmp(s, "no-renames"))
-               o->detect_rename = 0;
+               o->merge_detect_rename = 0;
        else if (!strcmp(s, "find-renames")) {
-               o->detect_rename = 1;
+               o->merge_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;
+               o->merge_detect_rename = 1;
        }
        else
                return -1;