commit-graph: implement git commit-graph read

diff --git a/builtin/commit-graph.c b/builtin/commit-graph.c
index 26b6360289389786cf457b4dfec26de3dbfd2f59..efd39331d7c54b6039352719bc70c6dccc17aeda 100644 (file)
--- a/builtin/commit-graph.c
+++ b/builtin/commit-graph.c
@@ -7,10 +7,16 @@
 
 static char const * const builtin_commit_graph_usage[] = {
        N_("git commit-graph [--object-dir <objdir>]"),
+       N_("git commit-graph read [--object-dir <objdir>]"),
        N_("git commit-graph write [--object-dir <objdir>]"),
        NULL
 };
 
+static const char * const builtin_commit_graph_read_usage[] = {
+       N_("git commit-graph read [--object-dir <objdir>]"),
+       NULL
+};
+
 static const char * const builtin_commit_graph_write_usage[] = {
        N_("git commit-graph write [--object-dir <objdir>]"),
        NULL
@@ -20,6 +26,54 @@ static struct opts_commit_graph {
        const char *obj_dir;
 } opts;
 
+static int graph_read(int argc, const char **argv)
+{
+       struct commit_graph *graph = NULL;
+       char *graph_name;
+
+       static struct option builtin_commit_graph_read_options[] = {
+               OPT_STRING(0, "object-dir", &opts.obj_dir,
+                       N_("dir"),
+                       N_("The object directory to store the graph")),
+               OPT_END(),
+       };
+
+       argc = parse_options(argc, argv, NULL,
+                            builtin_commit_graph_read_options,
+                            builtin_commit_graph_read_usage, 0);
+
+       if (!opts.obj_dir)
+               opts.obj_dir = get_object_directory();
+
+       graph_name = get_commit_graph_filename(opts.obj_dir);
+       graph = load_commit_graph_one(graph_name);
+
+       if (!graph)
+               die("graph file %s does not exist", graph_name);
+       FREE_AND_NULL(graph_name);
+
+       printf("header: %08x %d %d %d %d\n",
+               ntohl(*(uint32_t*)graph->data),
+               *(unsigned char*)(graph->data + 4),
+               *(unsigned char*)(graph->data + 5),
+               *(unsigned char*)(graph->data + 6),
+               *(unsigned char*)(graph->data + 7));
+       printf("num_commits: %u\n", graph->num_commits);
+       printf("chunks:");
+
+       if (graph->chunk_oid_fanout)
+               printf(" oid_fanout");
+       if (graph->chunk_oid_lookup)
+               printf(" oid_lookup");
+       if (graph->chunk_commit_data)
+               printf(" commit_metadata");
+       if (graph->chunk_large_edges)
+               printf(" large_edges");
+       printf("\n");
+
+       return 0;
+}
+
 static int graph_write(int argc, const char **argv)
 {
        static struct option builtin_commit_graph_write_options[] = {
@@ -60,6 +114,8 @@ int cmd_commit_graph(int argc, const char **argv, const char *prefix)
                             PARSE_OPT_STOP_AT_NON_OPTION);
 
        if (argc > 0) {
+               if (!strcmp(argv[0], "read"))
+                       return graph_read(argc, argv);
                if (!strcmp(argv[0], "write"))
                        return graph_write(argc, argv);
        }