Allow callers of unpack_trees() to handle failure

Return an error from unpack_trees() instead of calling die(), and exit
with an error in read-tree, builtin-commit, and diff-lib. merge-recursive
already expected an error return from unpack_trees, so it doesn't need to
be changed. The merge function can return negative to abort.

This will be used in builtin-checkout -m.

Signed-off-by: Daniel Barkalow <barkalow@iabervon.org>

diff --git a/builtin-commit.c b/builtin-commit.c
index c63ff826fc1c87c232b61c0059f12bb26f3098b2..5b5b7c0f4df81f4200707e0cbe688b3873443125 100644 (file)
--- a/builtin-commit.c
+++ b/builtin-commit.c
@@ -200,7 +200,8 @@ static void create_base_index(void)
                die("failed to unpack HEAD tree object");
        parse_tree(tree);
        init_tree_desc(&t, tree->buffer, tree->size);
-       unpack_trees(1, &t, &opts);
+       if (unpack_trees(1, &t, &opts))
+               exit(128); /* We've already reported the error, finish dying */
 }
 
 static char *prepare_index(int argc, const char **argv, const char *prefix)

diff --git a/builtin-read-tree.c b/builtin-read-tree.c
index 57854017535a36fc1fcd7bb997f198956391199d..1d9d125b91f976ebbc5ef0b1ca0fe7c0caeabb8a 100644 (file)
--- a/builtin-read-tree.c
+++ b/builtin-read-tree.c
@@ -268,7 +268,8 @@ int cmd_read_tree(int argc, const char **argv, const char *unused_prefix)
                parse_tree(tree);
                init_tree_desc(t+i, tree->buffer, tree->size);
        }
-       unpack_trees(nr_trees, t, &opts);
+       if (unpack_trees(nr_trees, t, &opts))
+               return 128;
 
        /*
         * When reading only one tree (either the most basic form,

diff --git a/diff-lib.c b/diff-lib.c
index 03eaa7cef35dfaec0a8f61b2b96892e5604ed731..94b150e830c5d9bd828a5e050166eed27e0b0e62 100644 (file)
--- a/diff-lib.c
+++ b/diff-lib.c
@@ -737,7 +737,8 @@ int run_diff_index(struct rev_info *revs, int cached)
        opts.unpack_data = revs;
 
        init_tree_desc(&t, tree->buffer, tree->size);
-       unpack_trees(1, &t, &opts);
+       if (unpack_trees(1, &t, &opts))
+               exit(128);
 
        diffcore_std(&revs->diffopt);
        diff_flush(&revs->diffopt);
@@ -789,6 +790,7 @@ int do_diff_cache(const unsigned char *tree_sha1, struct diff_options *opt)
        opts.unpack_data = &revs;
 
        init_tree_desc(&t, tree->buffer, tree->size);
-       unpack_trees(1, &t, &opts);
+       if (unpack_trees(1, &t, &opts))
+               exit(128);
        return 0;
 }

diff --git a/unpack-trees.c b/unpack-trees.c
index ff46fd62fdceeefc2ebd98ae1c9483964cb37bd5..9e6587f66186ef93c3403b15a016c00526cbc1e7 100644 (file)
--- a/unpack-trees.c
+++ b/unpack-trees.c
@@ -219,6 +219,8 @@ static int unpack_trees_rec(struct tree_entry_list **posns, int len,
                                }
 #endif
                                ret = o->fn(src, o, remove);
+                               if (ret < 0)
+                                       return ret;
 
 #if DBRT_DEBUG > 1
                                printf("Added %d entries\n", ret);
@@ -359,7 +361,7 @@ int unpack_trees(unsigned len, struct tree_desc *t, struct unpack_trees_options
        }
 
        if (o->trivial_merges_only && o->nontrivial_merge)
-               die("Merge requires file-level merging");
+               return error("Merge requires file-level merging");
 
        check_updates(active_cache, active_nr, o);
        return 0;
@@ -367,10 +369,10 @@ int unpack_trees(unsigned len, struct tree_desc *t, struct unpack_trees_options
 
 /* Here come the merge functions */
 
-static void reject_merge(struct cache_entry *ce)
+static int reject_merge(struct cache_entry *ce)
 {
-       die("Entry '%s' would be overwritten by merge. Cannot merge.",
-           ce->name);
+       return error("Entry '%s' would be overwritten by merge. Cannot merge.",
+                    ce->name);
 }
 
 static int same(struct cache_entry *a, struct cache_entry *b)
@@ -388,18 +390,18 @@ static int same(struct cache_entry *a, struct cache_entry *b)
  * When a CE gets turned into an unmerged entry, we
  * want it to be up-to-date
  */
-static void verify_uptodate(struct cache_entry *ce,
+static int verify_uptodate(struct cache_entry *ce,
                struct unpack_trees_options *o)
 {
        struct stat st;
 
        if (o->index_only || o->reset)
-               return;
+               return 0;
 
        if (!lstat(ce->name, &st)) {
                unsigned changed = ce_match_stat(ce, &st, CE_MATCH_IGNORE_VALID);
                if (!changed)
-                       return;
+                       return 0;
                /*
                 * NEEDSWORK: the current default policy is to allow
                 * submodule to be out of sync wrt the supermodule
@@ -408,12 +410,12 @@ static void verify_uptodate(struct cache_entry *ce,
                 * checked out.
                 */
                if (S_ISGITLINK(ce->ce_mode))
-                       return;
+                       return 0;
                errno = 0;
        }
        if (errno == ENOENT)
-               return;
-       die("Entry '%s' not uptodate. Cannot merge.", ce->name);
+               return 0;
+       return error("Entry '%s' not uptodate. Cannot merge.", ce->name);
 }
 
 static void invalidate_ce_path(struct cache_entry *ce)
@@ -479,7 +481,8 @@ static int verify_clean_subdirectory(struct cache_entry *ce, const char *action,
                 * ce->name is an entry in the subdirectory.
                 */
                if (!ce_stage(ce)) {
-                       verify_uptodate(ce, o);
+                       if (verify_uptodate(ce, o))
+                               return -1;
                        ce->ce_flags |= CE_REMOVE;
                }
                cnt++;
@@ -498,8 +501,8 @@ static int verify_clean_subdirectory(struct cache_entry *ce, const char *action,
                d.exclude_per_dir = o->dir->exclude_per_dir;
        i = read_directory(&d, ce->name, pathbuf, namelen+1, NULL);
        if (i)
-               die("Updating '%s' would lose untracked files in it",
-                   ce->name);
+               return error("Updating '%s' would lose untracked files in it",
+                            ce->name);
        free(pathbuf);
        return cnt;
 }
@@ -508,16 +511,16 @@ static int verify_clean_subdirectory(struct cache_entry *ce, const char *action,
  * We do not want to remove or overwrite a working tree file that
  * is not tracked, unless it is ignored.
  */
-static void verify_absent(struct cache_entry *ce, const char *action,
-               struct unpack_trees_options *o)
+static int verify_absent(struct cache_entry *ce, const char *action,
+                        struct unpack_trees_options *o)
 {
        struct stat st;
 
        if (o->index_only || o->reset || !o->update)
-               return;
+               return 0;
 
        if (has_symlink_leading_path(ce->name, NULL))
-               return;
+               return 0;
 
        if (!lstat(ce->name, &st)) {
                int cnt;
@@ -527,7 +530,7 @@ static void verify_absent(struct cache_entry *ce, const char *action,
                         * ce->name is explicitly excluded, so it is Ok to
                         * overwrite it.
                         */
-                       return;
+                       return 0;
                if (S_ISDIR(st.st_mode)) {
                        /*
                         * We are checking out path "foo" and
@@ -556,7 +559,7 @@ static void verify_absent(struct cache_entry *ce, const char *action,
                         * deleted entries here.
                         */
                        o->pos += cnt;
-                       return;
+                       return 0;
                }
 
                /*
@@ -568,12 +571,13 @@ static void verify_absent(struct cache_entry *ce, const char *action,
                if (0 <= cnt) {
                        struct cache_entry *ce = active_cache[cnt];
                        if (ce->ce_flags & CE_REMOVE)
-                               return;
+                               return 0;
                }
 
-               die("Untracked working tree file '%s' "
-                   "would be %s by merge.", ce->name, action);
+               return error("Untracked working tree file '%s' "
+                            "would be %s by merge.", ce->name, action);
        }
+       return 0;
 }
 
 static int merged_entry(struct cache_entry *merge, struct cache_entry *old,
@@ -591,12 +595,14 @@ static int merged_entry(struct cache_entry *merge, struct cache_entry *old,
                if (same(old, merge)) {
                        memcpy(merge, old, offsetof(struct cache_entry, name));
                } else {
-                       verify_uptodate(old, o);
+                       if (verify_uptodate(old, o))
+                               return -1;
                        invalidate_ce_path(old);
                }
        }
        else {
-               verify_absent(merge, "overwritten", o);
+               if (verify_absent(merge, "overwritten", o))
+                       return -1;
                invalidate_ce_path(merge);
        }
 
@@ -608,10 +614,12 @@ static int merged_entry(struct cache_entry *merge, struct cache_entry *old,
 static int deleted_entry(struct cache_entry *ce, struct cache_entry *old,
                struct unpack_trees_options *o)
 {
-       if (old)
-               verify_uptodate(old, o);
-       else
-               verify_absent(ce, "removed", o);
+       if (old) {
+               if (verify_uptodate(old, o))
+                       return -1;
+       } else
+               if (verify_absent(ce, "removed", o))
+                       return -1;
        ce->ce_flags |= CE_REMOVE;
        add_cache_entry(ce, ADD_CACHE_OK_TO_ADD|ADD_CACHE_OK_TO_REPLACE);
        invalidate_ce_path(ce);
@@ -699,7 +707,7 @@ int threeway_merge(struct cache_entry **stages,
        /* #14, #14ALT, #2ALT */
        if (remote && !df_conflict_head && head_match && !remote_match) {
                if (index && !same(index, remote) && !same(index, head))
-                       reject_merge(index);
+                       return reject_merge(index);
                return merged_entry(remote, index, o);
        }
        /*
@@ -707,7 +715,7 @@ int threeway_merge(struct cache_entry **stages,
         * make sure that it matches head.
         */
        if (index && !same(index, head)) {
-               reject_merge(index);
+               return reject_merge(index);
        }
 
        if (head) {
@@ -758,8 +766,10 @@ int threeway_merge(struct cache_entry **stages,
                        remove_entry(remove);
                        if (index)
                                return deleted_entry(index, index, o);
-                       else if (ce && !head_deleted)
-                               verify_absent(ce, "removed", o);
+                       else if (ce && !head_deleted) {
+                               if (verify_absent(ce, "removed", o))
+                                       return -1;
+                       }
                        return 0;
                }
                /*
@@ -775,7 +785,8 @@ int threeway_merge(struct cache_entry **stages,
         * conflict resolution files.
         */
        if (index) {
-               verify_uptodate(index, o);
+               if (verify_uptodate(index, o))
+                       return -1;
        }
 
        remove_entry(remove);
@@ -855,11 +866,11 @@ int twoway_merge(struct cache_entry **src,
                        /* all other failures */
                        remove_entry(remove);
                        if (oldtree)
-                               reject_merge(oldtree);
+                               return reject_merge(oldtree);
                        if (current)
-                               reject_merge(current);
+                               return reject_merge(current);
                        if (newtree)
-                               reject_merge(newtree);
+                               return reject_merge(newtree);
                        return -1;
                }
        }
@@ -886,7 +897,7 @@ int bind_merge(struct cache_entry **src,
                return error("Cannot do a bind merge of %d trees\n",
                             o->merge_size);
        if (a && old)
-               die("Entry '%s' overlaps.  Cannot bind.", a->name);
+               return error("Entry '%s' overlaps.  Cannot bind.", a->name);
        if (!a)
                return keep_entry(old, o);
        else