upload-pack: convert to a builtin

In order to allow for code sharing with the server-side of fetch in
protocol-v2 convert upload-pack to be a builtin.

Signed-off-by: Brandon Williams <bmwill@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

builtin/upload-pack.c

@@ -0,0 +1,67 @@
+#include "cache.h"
+#include "builtin.h"
+#include "exec_cmd.h"
+#include "pkt-line.h"
+#include "parse-options.h"
+#include "protocol.h"
+#include "upload-pack.h"
+
+static const char * const upload_pack_usage[] = {
+	N_("git upload-pack [<options>] <dir>"),
+	NULL
+};
+
+int cmd_upload_pack(int argc, const char **argv, const char *prefix)
+{
+	const char *dir;
+	int strict = 0;
+	struct upload_pack_options opts = { 0 };
+	struct option options[] = {
+		OPT_BOOL(0, "stateless-rpc", &opts.stateless_rpc,
+			 N_("quit after a single request/response exchange")),
+		OPT_BOOL(0, "advertise-refs", &opts.advertise_refs,
+			 N_("exit immediately after initial ref advertisement")),
+		OPT_BOOL(0, "strict", &strict,
+			 N_("do not try <directory>/.git/ if <directory> is no Git directory")),
+		OPT_INTEGER(0, "timeout", &opts.timeout,
+			    N_("interrupt transfer after <n> seconds of inactivity")),
+		OPT_END()
+	};
+
+	packet_trace_identity("upload-pack");
+	check_replace_refs = 0;
+
+	argc = parse_options(argc, argv, NULL, options, upload_pack_usage, 0);
+
+	if (argc != 1)
+		usage_with_options(upload_pack_usage, options);
+
+	if (opts.timeout)
+		opts.daemon_mode = 1;
+
+	setup_path();
+
+	dir = argv[0];
+
+	if (!enter_repo(dir, strict))
+		die("'%s' does not appear to be a git repository", dir);
+
+	switch (determine_protocol_version_server()) {
+	case protocol_v1:
+		/*
+		 * v1 is just the original protocol with a version string,
+		 * so just fall through after writing the version string.
+		 */
+		if (opts.advertise_refs || !opts.stateless_rpc)
+			packet_write_fmt(1, "version 1\n");
+
+		/* fallthrough */
+	case protocol_v0:
+		upload_pack(&opts);
+		break;
+	case protocol_unknown_version:
+		BUG("unknown protocol version");
+	}
+
+	return 0;
+}