SOFTWARE.
***/
+#include <sys/types.h>
#include <inttypes.h>
+#ifdef __cplusplus
+extern "C" {
+#endif
+
/* Reference implementation of a few systemd related interfaces for
- * writing daemons. These interfaces are trivial to implement, however
- * to simplify porting we provide this reference
- * implementation. Applications are free to reimplement the algorithms
- * described here. */
+ * writing daemons. These interfaces are trivial to implement. To
+ * simplify porting we provide this reference
+ * implementation. Applications are welcome to reimplement the
+ * algorithms described here, if they do not want to include these two
+ * source files. */
+
+#ifdef __GNUC__
+#define _sd_printf_attr_(a,b) __attribute__ ((format (printf, a, b)))
+#else
+#define _sd_printf_attr_(a,b)
+#endif
/*
Log levels for usage on stderr:
#define SD_LISTEN_FDS_START 3
/* Returns how many file descriptors have been passed, or a negative
- * errno code on failure. Optionally removes the $LISTEN_FDS and
- * $LISTEN_PID file descriptors from the environment
- * (recommended). You'll find the file descriptors passed as fds
- * SD_LISTEN_FDS_START to SD_LISTEN_FDS_START+r-1 if r is the return
- * value of this functioin. Returns a negative errno style error code
- * on failure. */
+ * errno code on failure. Optionally, removes the $LISTEN_FDS and
+ * $LISTEN_PID file descriptors from the environment (recommended, but
+ * problematic in threaded environments). If r is the return value of
+ * this function you'll find the file descriptors passed as fds
+ * SD_LISTEN_FDS_START to SD_LISTEN_FDS_START+r-1. Returns a negative
+ * errno style error code on failure. This function call ensures that
+ * the FD_CLOEXEC flag is set for the passed file descriptors, to make
+ * sure they are not passed on to child processes. If FD_CLOEXEC shall
+ * not be set, the caller needs to unset it after this call for all file
+ * descriptors that are used.*/
int sd_listen_fds(int unset_environment);
/* Helper call for identifying a passed file descriptor. Returns 1 if
int sd_is_fifo(int fd, const char *path);
/* Helper call for identifying a passed file descriptor. Returns 1 if
- * the file descriptor is a socket of the specified type (SOCK_DGRAM,
- * SOCK_STREAM, ...), 0 otherwise. If type is 0 a socket type check
- * will not be done and the call only verifies if the file descriptor
- * refers to a socket. Returns a negative errno style error code on
- * failure. */
-int sd_is_socket(int fd, int type, int listening);
+ * the file descriptor is a socket of the specified family (AF_INET,
+ * ...) and type (SOCK_DGRAM, SOCK_STREAM, ...), 0 otherwise. If
+ * family is 0 a socket family check will not be done. If type is 0 a
+ * socket type check will not be done and the call only verifies if
+ * the file descriptor refers to a socket. If listening is > 0 it is
+ * verified that the socket is in listening mode. (i.e. listen() has
+ * been called) If listening is == 0 it is verified that the socket is
+ * not in listening mode. If listening is < 0 no listening mode check
+ * is done. Returns a negative errno style error code on failure. */
+int sd_is_socket(int fd, int family, int type, int listening);
/* Helper call for identifying a passed file descriptor. Returns 1 if
- * the file descriptor is an Internet socket (either AF_INET or
- * AF_INET6) of the specified type (SOCK_DGRAM, SOCK_STREAM, ...), 0
- * otherwise. If type is 0 a socket type check will not be done. If
- * port is 0 a socket port check will not be done. Returns a negative
- * errno style error code on failure. */
-int sd_is_socket_inet(int fd, int type, int listening, uint16_t port);
+ * the file descriptor is an Internet socket, of the specified family
+ * (either AF_INET or AF_INET6) and the specified type (SOCK_DGRAM,
+ * SOCK_STREAM, ...), 0 otherwise. If version is 0 a protocol version
+ * check is not done. If type is 0 a socket type check will not be
+ * done. If port is 0 a socket port check will not be done. The
+ * listening flag is used the same way as in sd_is_socket(). Returns a
+ * negative errno style error code on failure. */
+int sd_is_socket_inet(int fd, int family, int type, int listening, uint16_t port);
/* Helper call for identifying a passed file descriptor. Returns 1 if
* the file descriptor is an AF_UNIX socket of the specified type
* a socket type check will not be done. If path is NULL a socket path
* check will not be done. For normal AF_UNIX sockets set length to
* 0. For abstract namespace sockets set length to the length of the
- * socket name (excluding the initial 0 byte). Returns a negative
+ * socket name (including the initial 0 byte), and pass the full
+ * socket path in path (including the initial 0 byte). The listening
+ * flag is used the same way as in sd_is_socket(). Returns a negative
* errno style error code on failure. */
int sd_is_socket_unix(int fd, int type, int listening, const char *path, size_t length);
+/* Informs systemd about changed daemon state. This takes a numeber of
+ * newline seperated environment-style variable assignments in a
+ * string. The following strings are known:
+ *
+ * READY=1 Tells systemd that daemon startup is finished (only
+ * relevant for services of Type=notify). The passed
+ * argument is a boolean "1" or "0". Since there is
+ * little value in signalling non-readiness the only
+ * value daemons should send is "READY=1".
+ *
+ * STATUS=... Passes a single-line status string back to systemd
+ * that describes the daemon state. This is free-from
+ * and can be used for various purposes: general state
+ * feedback, fsck-like programs could pass completion
+ * percentages and failing programs could pass a human
+ * readable error message. Example: "STATUS=Completed
+ * 66% of file system check..."
+ *
+ * ERRNO=... If a daemon fails, the errno-style error code,
+ * formatted as string. Example: "ERRNO=2" for ENOENT.
+ *
+ * BUSERROR=... If a daemon fails, the D-Bus error-style error
+ * code. Example: "BUSERROR=org.freedesktop.DBus.Error.TimedOut"
+ *
+ * MAINPID=... The main pid of a daemon, in case systemd did not
+ * fork off the process itself. Example: "MAINPID=4711"
+ *
+ * Daemons can choose to send additional variables.
+ *
+ * Returns a negative errno-style error code on failure. Returns > 0
+ * if systemd could be notified, 0 if it couldn't possibly because
+ * systemd is not running.
+ *
+ * See sd_notifyf() for more complete examples.
+ */
+int sd_notify(int unset_environment, const char *state);
+
+/* Similar to sd_send_state() but takes a format string.
+ *
+ * Example 1: A daemon could send the following after initialization:
+ *
+ * sd_notifyf(0, "READY=1\n"
+ * "STATUS=Processing requests...\n"
+ * "MAINPID=%lu",
+ * (unsigned long) getpid());
+ *
+ * Example 2: A daemon could send the following shortly before
+ * exiting, on failure:
+ *
+ * sd_notifyf(0, "STATUS=Failed to start up: %s\n"
+ * "ERRNO=%i",
+ * strerror(errno),
+ * errno);
+ */
+int sd_notifyf(int unset_environment, const char *format, ...) _sd_printf_attr_(2,3);
+
+#ifdef __cplusplus
+}
+#endif
+
#endif
~ianmdlvl / elogind.git / blobdiff