commit-graph write: don't die if the existing graph is corrupt

diff --git a/commit-graph.c b/commit-graph.c
index f8201d888b9a26299b3c7b0eb7cc48ad546dd7f2..34ecaaf857fb802bf15ca7a1154aac01043bfa38 100644 (file)
--- a/commit-graph.c
+++ b/commit-graph.c
@@ -80,25 +80,30 @@ static int commit_graph_compatible(struct repository *r)
        return 1;
 }
 
-struct commit_graph *load_commit_graph_one(const char *graph_file)
+int open_commit_graph(const char *graph_file, int *fd, struct stat *st)
+{
+       *fd = git_open(graph_file);
+       if (*fd < 0)
+               return 0;
+       if (fstat(*fd, st)) {
+               close(*fd);
+               return 0;
+       }
+       return 1;
+}
+
+struct commit_graph *load_commit_graph_one_fd_st(int fd, struct stat *st)
 {
        void *graph_map;
        size_t graph_size;
-       struct stat st;
        struct commit_graph *ret;
-       int fd = git_open(graph_file);
 
-       if (fd < 0)
-               return NULL;
-       if (fstat(fd, &st)) {
-               close(fd);
-               return NULL;
-       }
-       graph_size = xsize_t(st.st_size);
+       graph_size = xsize_t(st->st_size);
 
        if (graph_size < GRAPH_MIN_SIZE) {
                close(fd);
-               die(_("graph file %s is too small"), graph_file);
+               error(_("commit-graph file is too small"));
+               return NULL;
        }
        graph_map = xmmap(NULL, graph_size, PROT_READ, MAP_PRIVATE, fd, 0);
        ret = parse_commit_graph(graph_map, fd, graph_size);
@@ -106,7 +111,6 @@ struct commit_graph *load_commit_graph_one(const char *graph_file)
        if (!ret) {
                munmap(graph_map, graph_size);
                close(fd);
-               exit(1);
        }
 
        return ret;
@@ -269,6 +273,19 @@ struct commit_graph *parse_commit_graph(void *graph_map, int fd,
        return graph;
 }
 
+static struct commit_graph *load_commit_graph_one(const char *graph_file)
+{
+
+       struct stat st;
+       int fd;
+       int open_ok = open_commit_graph(graph_file, &fd, &st);
+
+       if (!open_ok)
+               return NULL;
+
+       return load_commit_graph_one_fd_st(fd, &st);
+}
+
 static void prepare_commit_graph_one(struct repository *r, const char *obj_dir)
 {
        char *graph_name;
@@ -294,6 +311,10 @@ static int prepare_commit_graph(struct repository *r)
        struct object_directory *odb;
        int config_value;
 
+       if (git_env_bool(GIT_TEST_COMMIT_GRAPH_DIE_ON_LOAD, 0))
+               die("dying as requested by the '%s' variable on commit-graph load!",
+                   GIT_TEST_COMMIT_GRAPH_DIE_ON_LOAD);
+
        if (r->objects->commit_graph_attempted)
                return !!r->objects->commit_graph;
        r->objects->commit_graph_attempted = 1;
@@ -558,7 +579,7 @@ static void write_graph_chunk_data(struct hashfile *f, int hash_len,
                uint32_t packedDate[2];
                display_progress(progress, ++*progress_cnt);
 
-               parse_commit(*list);
+               parse_commit_no_graph(*list);
                hashwrite(f, get_commit_tree_oid(*list)->hash, hash_len);
 
                parent = (*list)->parents;
@@ -755,7 +776,7 @@ static void close_reachable(struct packed_oid_list *oids, int report_progress)
                display_progress(progress, i + 1);
                commit = lookup_commit(the_repository, &oids->list[i]);
 
-               if (commit && !parse_commit(commit))
+               if (commit && !parse_commit_no_graph(commit))
                        add_missing_parents(oids, commit);
        }
        stop_progress(&progress);
@@ -1004,7 +1025,7 @@ void write_commit_graph(const char *obj_dir,
                        continue;
 
                commits.list[commits.nr] = lookup_commit(the_repository, &oids.list[i]);
-               parse_commit(commits.list[commits.nr]);
+               parse_commit_no_graph(commits.list[commits.nr]);
 
                for (parent = commits.list[commits.nr]->parents;
                     parent; parent = parent->next)