1 files changed, 112 insertions, 0 deletions
diff --git a/libdaemon/client/daemon-client.h b/libdaemon/client/daemon-client.h
new file mode 100644
index 0000000..6ba65e6
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+++ b/libdaemon/client/daemon-client.h
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+/*
+ * Copyright (C) 2011-2012 Red Hat, Inc.
+ *
+ * This file is part of LVM2.
+ *
+ * This copyrighted material is made available to anyone wishing to use,
+ * modify, copy, or redistribute it subject to the terms and conditions
+ * of the GNU Lesser General Public License v.2.1.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#ifndef _LVM_DAEMON_COMMON_CLIENT_H
+#define _LVM_DAEMON_COMMON_CLIENT_H
+
+#include "libdevmapper.h"
+#include "config-util.h"
+
+typedef struct {
+	int socket_fd; /* the fd we use to talk to the daemon */
+	const char *protocol;
+	int protocol_version;  /* version of the protocol the daemon uses */
+	int error;
+} daemon_handle;
+
+typedef struct {
+	const char *path; /* the binary of the daemon */
+	const char *socket; /* path to the comms socket */
+	unsigned autostart:1; /* start the daemon if not running? */
+
+	/*
+	 * If the following are not NULL/0, an attempt to talk to a daemon which
+	 * uses a different protocol or version will fail.
+	 */
+	const char *protocol;
+	int protocol_version;
+} daemon_info;
+
+typedef struct {
+	struct buffer buffer;
+	/*
+	 * The request looks like this:
+	 *    request = "id"
+	 *    arg_foo = "something"
+	 *    arg_bar = 3
+	 *    arg_wibble {
+	 *        something_special = "here"
+	 *        amount = 75
+	 *        knobs = [ "twiddle", "tweak" ]
+	 *    }
+	 */
+	struct dm_config_tree *cft;
+} daemon_request;
+
+typedef struct {
+	int error; /* 0 for success */
+	struct buffer buffer;
+	struct dm_config_tree *cft; /* parsed reply, if available */
+} daemon_reply;
+
+/*
+ * Open the communication channel to the daemon. If the daemon is not running,
+ * it may be autostarted based on the binary path provided in the info (this
+ * will only happen if autostart is set to true). If the call fails for any
+ * reason, daemon_handle_valid(h) for the response will return false. Otherwise,
+ * the connection is good to start serving requests.
+ */
+daemon_handle daemon_open(daemon_info i);
+
+/*
+ * Send a request to the daemon, waiting for the reply. All communication with
+ * the daemon is synchronous. The function handles the IO details and parses the
+ * response, handling common error conditions. See "daemon_reply" for details.
+ *
+ * In case the request contains a non-NULL buffer pointer, this buffer is sent
+ * *verbatim* to the server. In this case, the cft pointer may be NULL (but will
+ * be ignored even if non-NULL). If the buffer is NULL, the cft is required to
+ * be a valid pointer, and is used to build up the request.
+ */
+daemon_reply daemon_send(daemon_handle h, daemon_request r);
+
+/*
+ * A simple interface to daemon_send. This function just takes the command id
+ * and possibly a list of parameters (of the form "name = %?", "value"). The
+ * type (string, integer) of the value is indicated by a character substituted
+ * for ? in %?: d for integer, s for string.
+ */
+daemon_reply daemon_send_simple(daemon_handle h, const char *id, ...);
+daemon_reply daemon_send_simple_v(daemon_handle h, const char *id, va_list ap);
+
+daemon_request daemon_request_make(const char *id);
+int daemon_request_extend(daemon_request r, ...);
+int daemon_request_extend_v(daemon_request r, va_list ap);
+void daemon_request_destroy(daemon_request r);
+
+void daemon_reply_destroy(daemon_reply r);
+
+static inline int64_t daemon_reply_int(daemon_reply r, const char *path, int64_t def) {
+	return dm_config_find_int64(r.cft->root, path, def);
+}
+
+static inline const char *daemon_reply_str(daemon_reply r, const char *path, const char *def) {
+	return dm_config_find_str(r.cft->root, path, def);
+}
+
+
+/* Shut down the communication to the daemon. Compulsory. */
+void daemon_close(daemon_handle h);
+
+#endif