1 files changed, 107 insertions, 0 deletions
diff --git a/connected.c b/connected.c
new file mode 100644
index 0000000000..f416b05051
--- /dev/null
+++ b/connected.c
@@ -0,0 +1,107 @@
+#include "cache.h"
+#include "run-command.h"
+#include "sigchain.h"
+#include "connected.h"
+#include "transport.h"
+#include "packfile.h"
+
+/*
+ * If we feed all the commits we want to verify to this command
+ *
+ *  $ git rev-list --objects --stdin --not --all
+ *
+ * and if it does not error out, that means everything reachable from
+ * these commits locally exists and is connected to our existing refs.
+ * Note that this does _not_ validate the individual objects.
+ *
+ * Returns 0 if everything is connected, non-zero otherwise.
+ */
+int check_connected(sha1_iterate_fn fn, void *cb_data,
+		    struct check_connected_options *opt)
+{
+	struct child_process rev_list = CHILD_PROCESS_INIT;
+	struct check_connected_options defaults = CHECK_CONNECTED_INIT;
+	char commit[41];
+	unsigned char sha1[20];
+	int err = 0;
+	struct packed_git *new_pack = NULL;
+	struct transport *transport;
+	size_t base_len;
+
+	if (!opt)
+		opt = &defaults;
+	transport = opt->transport;
+
+	if (fn(cb_data, sha1)) {
+		if (opt->err_fd)
+			close(opt->err_fd);
+		return err;
+	}
+
+	if (transport && transport->smart_options &&
+	    transport->smart_options->self_contained_and_connected &&
+	    transport->pack_lockfile &&
+	    strip_suffix(transport->pack_lockfile, ".keep", &base_len)) {
+		struct strbuf idx_file = STRBUF_INIT;
+		strbuf_add(&idx_file, transport->pack_lockfile, base_len);
+		strbuf_addstr(&idx_file, ".idx");
+		new_pack = add_packed_git(idx_file.buf, idx_file.len, 1);
+		strbuf_release(&idx_file);
+	}
+
+	if (opt->shallow_file) {
+		argv_array_push(&rev_list.args, "--shallow-file");
+		argv_array_push(&rev_list.args, opt->shallow_file);
+	}
+	argv_array_push(&rev_list.args,"rev-list");
+	argv_array_push(&rev_list.args, "--objects");
+	argv_array_push(&rev_list.args, "--stdin");
+	argv_array_push(&rev_list.args, "--not");
+	argv_array_push(&rev_list.args, "--all");
+	argv_array_push(&rev_list.args, "--quiet");
+	if (opt->progress)
+		argv_array_pushf(&rev_list.args, "--progress=%s",
+				 _("Checking connectivity"));
+
+	rev_list.git_cmd = 1;
+	rev_list.env = opt->env;
+	rev_list.in = -1;
+	rev_list.no_stdout = 1;
+	if (opt->err_fd)
+		rev_list.err = opt->err_fd;
+	else
+		rev_list.no_stderr = opt->quiet;
+
+	if (start_command(&rev_list))
+		return error(_("Could not run 'git rev-list'"));
+
+	sigchain_push(SIGPIPE, SIG_IGN);
+
+	commit[40] = '\n';
+	do {
+		/*
+		 * If index-pack already checked that:
+		 * - there are no dangling pointers in the new pack
+		 * - the pack is self contained
+		 * Then if the updated ref is in the new pack, then we
+		 * are sure the ref is good and not sending it to
+		 * rev-list for verification.
+		 */
+		if (new_pack && find_pack_entry_one(sha1, new_pack))
+			continue;
+
+		memcpy(commit, sha1_to_hex(sha1), 40);
+		if (write_in_full(rev_list.in, commit, 41) < 0) {
+			if (errno != EPIPE && errno != EINVAL)
+				error_errno(_("failed write to rev-list"));
+			err = -1;
+			break;
+		}
+	} while (!fn(cb_data, sha1));
+
+	if (close(rev_list.in))
+		err = error_errno(_("failed to close rev-list's stdin"));
+
+	sigchain_pop(SIGPIPE);
+	return finish_command(&rev_list) || err;
+}