Code

Convert memcpy(a,b,20) to hashcpy(a,b).
[git.git] / merge-recursive.c
index b8b095179bfb581611ced221e1bdcca2b05a07b9..8a2f69731e88198f7669343e7c96853fc24428f9 100644 (file)
@@ -116,6 +116,7 @@ static void output_commit_title(struct commit *commit)
        }
 }
 
+static const char *current_index_file = NULL;
 static const char *original_index_file;
 static const char *temporary_index_file;
 static int cache_dirty = 0;
@@ -124,12 +125,10 @@ static int flush_cache(void)
 {
        /* flush temporary index */
        struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
-       int fd = hold_lock_file_for_update(lock, getenv("GIT_INDEX_FILE"));
-       if (fd < 0)
-               die("could not lock %s", lock->filename);
+       int fd = hold_lock_file_for_update(lock, current_index_file, 1);
        if (write_cache(fd, active_cache, active_nr) ||
                        close(fd) || commit_lock_file(lock))
-               die ("unable to write %s", getenv("GIT_INDEX_FILE"));
+               die ("unable to write %s", current_index_file);
        discard_cache();
        cache_dirty = 0;
        return 0;
@@ -137,11 +136,12 @@ static int flush_cache(void)
 
 static void setup_index(int temp)
 {
-       const char *idx = temp ? temporary_index_file: original_index_file;
-       if (cache_dirty)
-               die("fatal: cache changed flush_cache();");
+       current_index_file = temp ? temporary_index_file: original_index_file;
+       if (cache_dirty) {
+               discard_cache();
+               cache_dirty = 0;
+       }
        unlink(temporary_index_file);
-       setenv("GIT_INDEX_FILE", idx, 1);
        discard_cache();
 }
 
@@ -158,7 +158,7 @@ static struct cache_entry *make_cache_entry(unsigned int mode,
        size = cache_entry_size(len);
        ce = xcalloc(1, size);
 
-       memcpy(ce->sha1, sha1, 20);
+       hashcpy(ce->sha1, sha1);
        memcpy(ce->name, path, len);
        ce->ce_flags = create_ce_flags(len, stage);
        ce->ce_mode = create_ce_mode(mode);
@@ -174,7 +174,7 @@ static int add_cacheinfo(unsigned int mode, const unsigned char *sha1,
 {
        struct cache_entry *ce;
        if (!cache_dirty)
-               read_cache_from(getenv("GIT_INDEX_FILE"));
+               read_cache_from(current_index_file);
        cache_dirty++;
        ce = make_cache_entry(mode, sha1 ? sha1 : null_sha1, path, stage, refresh);
        if (!ce)
@@ -223,7 +223,7 @@ static int git_merge_trees(int index_only,
        struct unpack_trees_options opts;
 
        if (!cache_dirty) {
-               read_cache_from(getenv("GIT_INDEX_FILE"));
+               read_cache_from(current_index_file);
                cache_dirty = 1;
        }
 
@@ -260,7 +260,7 @@ static struct tree *git_write_tree(void)
                                return NULL;
                }
        } else
-               read_cache_from(getenv("GIT_INDEX_FILE"));
+               read_cache_from(current_index_file);
 
        if (!active_cache_tree)
                active_cache_tree = cache_tree();
@@ -338,7 +338,7 @@ static struct path_list *get_unmerged(void)
 
        unmerged->strdup_paths = 1;
        if (!cache_dirty) {
-               read_cache_from(getenv("GIT_INDEX_FILE"));
+               read_cache_from(current_index_file);
                cache_dirty++;
        }
        for (i = 0; i < active_nr; i++) {
@@ -355,7 +355,7 @@ static struct path_list *get_unmerged(void)
                }
                e = item->util;
                e->stages[ce_stage(ce)].mode = ntohl(ce->ce_mode);
-               memcpy(e->stages[ce_stage(ce)].sha, ce->sha1, 20);
+               hashcpy(e->stages[ce_stage(ce)].sha, ce->sha1);
        }
 
        return unmerged;
@@ -468,10 +468,6 @@ static int remove_path(const char *name)
        return ret;
 }
 
-/*
- * TODO: once we no longer call external programs, we'd probably be better off
- * not setting / getting the environment variable GIT_INDEX_FILE all the time.
- */
 int remove_file(int clean, const char *path)
 {
        int update_cache = index_only || clean;
@@ -479,7 +475,7 @@ int remove_file(int clean, const char *path)
 
        if (update_cache) {
                if (!cache_dirty)
-                       read_cache_from(getenv("GIT_INDEX_FILE"));
+                       read_cache_from(current_index_file);
                cache_dirty++;
                if (remove_file_from_cache(path))
                        return -1;
@@ -640,10 +636,10 @@ static struct merge_file_info merge_file(struct diff_filespec *o,
                result.clean = 0;
                if (S_ISREG(a->mode)) {
                        result.mode = a->mode;
-                       memcpy(result.sha, a->sha1, 20);
+                       hashcpy(result.sha, a->sha1);
                } else {
                        result.mode = b->mode;
-                       memcpy(result.sha, b->sha1, 20);
+                       hashcpy(result.sha, b->sha1);
                }
        } else {
                if (!sha_eq(a->sha1, o->sha1) && !sha_eq(b->sha1, o->sha1))
@@ -652,9 +648,9 @@ static struct merge_file_info merge_file(struct diff_filespec *o,
                result.mode = a->mode == o->mode ? b->mode: a->mode;
 
                if (sha_eq(a->sha1, o->sha1))
-                       memcpy(result.sha, b->sha1, 20);
+                       hashcpy(result.sha, b->sha1);
                else if (sha_eq(b->sha1, o->sha1))
-                       memcpy(result.sha, a->sha1, 20);
+                       hashcpy(result.sha, a->sha1);
                else if (S_ISREG(a->mode)) {
                        int code = 1, fd;
                        struct stat st;
@@ -703,7 +699,7 @@ static struct merge_file_info merge_file(struct diff_filespec *o,
                        if (!(S_ISLNK(a->mode) || S_ISLNK(b->mode)))
                                die("cannot merge modes?");
 
-                       memcpy(result.sha, a->sha1, 20);
+                       hashcpy(result.sha, a->sha1);
 
                        if (!sha_eq(a->sha1, b->sha1))
                                result.clean = 0;
@@ -1100,11 +1096,11 @@ static int process_entry(const char *path, struct stage_data *entry,
 
                output("Auto-merging %s", path);
                o.path = a.path = b.path = (char *)path;
-               memcpy(o.sha1, o_sha, 20);
+               hashcpy(o.sha1, o_sha);
                o.mode = o_mode;
-               memcpy(a.sha1, a_sha, 20);
+               hashcpy(a.sha1, a_sha);
                a.mode = a_mode;
-               memcpy(b.sha1, b_sha, 20);
+               hashcpy(b.sha1, b_sha);
                b.mode = b_mode;
 
                mfi = merge_file(&o, &a, &b,
@@ -1195,6 +1191,17 @@ static int merge_trees(struct tree *head,
        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 cleaness of the merge.
@@ -1220,13 +1227,25 @@ int merge(struct commit *h1,
        if (ancestor)
                commit_list_insert(ancestor, &ca);
        else
-               ca = get_merge_bases(h1, h2, 1);
+               ca = reverse_commit_list(get_merge_bases(h1, h2, 1));
 
        output("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));
+               unsigned char hdr[40];
+               int hdrlen;
+
+               tree->object.parsed = 1;
+               tree->object.type = OBJ_TREE;
+               write_sha1_file_prepare(NULL, 0, tree_type, tree->object.sha1,
+                                       hdr, &hdrlen);
+               merged_common_ancestors = make_virtual_commit(tree, "ancestor");
+       }
 
        for (iter = ca; iter; iter = iter->next) {
                output_indent = call_depth + 1;