Push code for transport library

This moves the code to call push backends into a library that can be
extended to make matching fetch and push decisions based on the URL it
gets, and which could be changed to have built-in implementations
instead of calling external programs.

Signed-off-by: Daniel Barkalow <barkalow@iabervon.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 196 insertions, 0 deletions

diff --git a/transport.c b/transport.c
new file mode 100644
index 0000000000..edbdc3c60e
--- /dev/null
+++ b/transport.c
@@ -0,0 +1,196 @@
+#include "cache.h"
+#include "transport.h"
+#include "run-command.h"
+
+static const struct transport_ops rsync_transport;
+
+static int curl_transport_push(struct transport *transport, int refspec_nr, const char **refspec, int flags) {
+	const char **argv;
+	int argc;
+	int err;
+
+	argv = xmalloc((refspec_nr + 11) * sizeof(char *));
+	argv[0] = "http-push";
+	argc = 1;
+	if (flags & TRANSPORT_PUSH_ALL)
+		argv[argc++] = "--all";
+	if (flags & TRANSPORT_PUSH_FORCE)
+		argv[argc++] = "--force";
+	argv[argc++] = transport->url;
+	while (refspec_nr--)
+		argv[argc++] = *refspec++;
+	argv[argc] = NULL;
+	err = run_command_v_opt(argv, RUN_GIT_CMD);
+	switch (err) {
+	case -ERR_RUN_COMMAND_FORK:
+		error("unable to fork for %s", argv[0]);
+	case -ERR_RUN_COMMAND_EXEC:
+		error("unable to exec %s", argv[0]);
+		break;
+	case -ERR_RUN_COMMAND_WAITPID:
+	case -ERR_RUN_COMMAND_WAITPID_WRONG_PID:
+	case -ERR_RUN_COMMAND_WAITPID_SIGNAL:
+	case -ERR_RUN_COMMAND_WAITPID_NOEXIT:
+		error("%s died with strange error", argv[0]);
+	}
+	return !!err;
+}
+
+static const struct transport_ops curl_transport = {
+	/* set_option */	NULL,
+	/* push */		curl_transport_push
+};
+
+static const struct transport_ops bundle_transport = {
+};
+
+struct git_transport_data {
+	unsigned thin : 1;
+
+	const char *receivepack;
+};
+
+static int set_git_option(struct transport *connection,
+			  const char *name, const char *value)
+{
+	struct git_transport_data *data = connection->data;
+	if (!strcmp(name, TRANS_OPT_RECEIVEPACK)) {
+		data->receivepack = value;
+		return 0;
+	} else if (!strcmp(name, TRANS_OPT_THIN)) {
+		data->thin = !!value;
+		return 0;
+	}
+	return 1;
+}
+
+static int git_transport_push(struct transport *transport, int refspec_nr, const char **refspec, int flags) {
+	struct git_transport_data *data = transport->data;
+	const char **argv;
+	char *rem;
+	int argc;
+	int err;
+
+	argv = xmalloc((refspec_nr + 11) * sizeof(char *));
+	argv[0] = "send-pack";
+	argc = 1;
+	if (flags & TRANSPORT_PUSH_ALL)
+		argv[argc++] = "--all";
+	if (flags & TRANSPORT_PUSH_FORCE)
+		argv[argc++] = "--force";
+	if (data->receivepack) {
+		char *rp = xmalloc(strlen(data->receivepack) + 16);
+		sprintf(rp, "--receive-pack=%s", data->receivepack);
+		argv[argc++] = rp;
+	}
+	if (data->thin)
+		argv[argc++] = "--thin";
+	rem = xmalloc(strlen(transport->remote->name) + 10);
+	sprintf(rem, "--remote=%s", transport->remote->name);
+	argv[argc++] = rem;
+	argv[argc++] = transport->url;
+	while (refspec_nr--)
+		argv[argc++] = *refspec++;
+	argv[argc] = NULL;
+	err = run_command_v_opt(argv, RUN_GIT_CMD);
+	switch (err) {
+	case -ERR_RUN_COMMAND_FORK:
+		error("unable to fork for %s", argv[0]);
+	case -ERR_RUN_COMMAND_EXEC:
+		error("unable to exec %s", argv[0]);
+		break;
+	case -ERR_RUN_COMMAND_WAITPID:
+	case -ERR_RUN_COMMAND_WAITPID_WRONG_PID:
+	case -ERR_RUN_COMMAND_WAITPID_SIGNAL:
+	case -ERR_RUN_COMMAND_WAITPID_NOEXIT:
+		error("%s died with strange error", argv[0]);
+	}
+	return !!err;
+}
+
+static const struct transport_ops git_transport = {
+	/* set_option */	set_git_option,
+	/* push */		git_transport_push
+};
+
+static int is_local(const char *url)
+{
+	const char *colon = strchr(url, ':');
+	const char *slash = strchr(url, '/');
+	return !colon || (slash && slash < colon);
+}
+
+static int is_file(const char *url)
+{
+	struct stat buf;
+	if (stat(url, &buf))
+		return 0;
+	return S_ISREG(buf.st_mode);
+}
+
+struct transport *transport_get(struct remote *remote, const char *url,
+				int fetch)
+{
+	struct transport *ret = NULL;
+	if (!prefixcmp(url, "rsync://")) {
+		ret = xmalloc(sizeof(*ret));
+		ret->data = NULL;
+		ret->ops = &rsync_transport;
+	} else if (!prefixcmp(url, "http://") || !prefixcmp(url, "https://") ||
+		   !prefixcmp(url, "ftp://")) {
+		ret = xmalloc(sizeof(*ret));
+		ret->ops = &curl_transport;
+		ret->data = NULL;
+	} else if (is_local(url) && is_file(url)) {
+		ret = xmalloc(sizeof(*ret));
+		ret->data = NULL;
+		ret->ops = &bundle_transport;
+	} else {
+		struct git_transport_data *data = xcalloc(1, sizeof(*data));
+		ret = xcalloc(1, sizeof(*ret));
+		ret->data = data;
+		data->thin = 1;
+		data->receivepack = "git-receive-pack";
+		if (remote && remote->receivepack)
+			data->receivepack = remote->receivepack;
+		ret->ops = &git_transport;
+	}
+	if (ret) {
+		ret->remote = remote;
+		ret->url = url;
+		ret->fetch = !!fetch;
+	}
+	return ret;
+}
+
+int transport_set_option(struct transport *transport,
+			 const char *name, const char *value)
+{
+	int ret = 1;
+	if (transport->ops->set_option)
+		ret = transport->ops->set_option(transport, name, value);
+	if (ret < 0)
+		fprintf(stderr, "For '%s' option %s cannot be set to '%s'\n",
+			transport->url, name, value);
+	if (ret > 0)
+		fprintf(stderr, "For '%s' option %s is ignored\n",
+			transport->url, name);
+	return ret;
+}
+
+int transport_push(struct transport *transport,
+		   int refspec_nr, const char **refspec, int flags)
+{
+	if (!transport->ops->push)
+		return 1;
+	return transport->ops->push(transport, refspec_nr, refspec, flags);
+}
+
+int transport_disconnect(struct transport *transport)
+{
+	int ret = 0;
+	if (transport->ops->disconnect)
+		ret = transport->ops->disconnect(transport);
+	free(transport);
+	return ret;
+}