diff options
Diffstat (limited to 'src/nxt_socketpair.c')
| -rw-r--r-- | src/nxt_socketpair.c | 291 |
1 files changed, 291 insertions, 0 deletions
diff --git a/src/nxt_socketpair.c b/src/nxt_socketpair.c new file mode 100644 index 00000000..20336d38 --- /dev/null +++ b/src/nxt_socketpair.c @@ -0,0 +1,291 @@ + +/* + * Copyright (C) Igor Sysoev + * Copyright (C) NGINX, Inc. + */ + +#include <nxt_main.h> + + +/* + * SOCK_SEQPACKET protocol is supported for AF_UNIX in Solaris 8 X/Open + * sockets, Linux 2.6.4, FreeBSD 9.0, NetBSD 6.0, and OpenBSD 5.0. + */ + +/* SOCK_SEQPACKET is disabled to test SOCK_DGRAM on all platforms. */ +#if (0 || NXT_HAVE_AF_UNIX_SOCK_SEQPACKET) +#define NXT_UNIX_SOCKET SOCK_SEQPACKET +#else +#define NXT_UNIX_SOCKET SOCK_DGRAM +#endif + + +static ssize_t nxt_sendmsg(nxt_socket_t s, nxt_fd_t fd, nxt_iobuf_t *iob, + nxt_uint_t niob); +static ssize_t nxt_recvmsg(nxt_socket_t s, nxt_fd_t *fd, nxt_iobuf_t *iob, + nxt_uint_t niob); + + +nxt_int_t +nxt_socketpair_create(nxt_socket_t *pair) +{ + if (nxt_slow_path(socketpair(AF_UNIX, NXT_UNIX_SOCKET, 0, pair) != 0)) { + nxt_thread_log_alert("socketpair() failed %E", nxt_errno); + return NXT_ERROR; + } + + nxt_thread_log_debug("socketpair(): %d:%d", pair[0], pair[1]); + + if (nxt_slow_path(nxt_socket_nonblocking(pair[0]) != NXT_OK)) { + goto fail; + } + + if (nxt_slow_path(fcntl(pair[0], F_SETFD, FD_CLOEXEC) == -1)) { + goto fail; + } + + if (nxt_slow_path(nxt_socket_nonblocking(pair[1]) != NXT_OK)) { + goto fail; + } + + if (nxt_slow_path(fcntl(pair[1], F_SETFD, FD_CLOEXEC) == -1)) { + goto fail; + } + + return NXT_OK; + +fail: + + nxt_socketpair_close(pair); + + return NXT_ERROR; +} + + +void +nxt_socketpair_close(nxt_socket_t *pair) +{ + nxt_socket_close(pair[0]); + nxt_socket_close(pair[1]); +} + + +ssize_t +nxt_socketpair_send(nxt_event_fd_t *ev, nxt_fd_t fd, nxt_iobuf_t *iob, + nxt_uint_t niob) +{ + ssize_t n; + nxt_err_t err; + + for ( ;; ) { + n = nxt_sendmsg(ev->fd, fd, iob, niob); + + err = (n == -1) ? nxt_socket_errno : 0; + + nxt_log_debug(ev->log, "sendmsg(%d, %FD, %ui): %z", + ev->fd, fd, niob, n); + + if (n > 0) { + return n; + } + + /* n == -1 */ + + switch (err) { + + case NXT_EAGAIN: + nxt_log_debug(ev->log, "sendmsg(%d) not ready", ev->fd); + ev->write_ready = 0; + return NXT_AGAIN; + + case NXT_EINTR: + nxt_log_debug(ev->log, "sendmsg(%d) interrupted", ev->fd); + continue; + + default: + nxt_log_error(NXT_LOG_CRIT, ev->log, + "sendmsg(%d, %FD, %ui) failed %E", + ev->fd, fd, niob, err); + return NXT_ERROR; + } + } +} + + +ssize_t +nxt_socketpair_recv(nxt_event_fd_t *ev, nxt_fd_t *fd, nxt_iobuf_t *iob, + nxt_uint_t niob) +{ + ssize_t n; + nxt_err_t err; + + for ( ;; ) { + n = nxt_recvmsg(ev->fd, fd, iob, niob); + + err = (n == -1) ? nxt_socket_errno : 0; + + nxt_log_debug(ev->log, "recvmsg(%d, %FD, %ui): %z", + ev->fd, *fd, niob, n); + + if (n > 0) { + return n; + } + + if (n == 0) { + ev->closed = 1; + ev->read_ready = 0; + return n; + } + + /* n == -1 */ + + switch (err) { + + case NXT_EAGAIN: + nxt_log_debug(ev->log, "recvmsg(%d) not ready", ev->fd); + ev->read_ready = 0; + return NXT_AGAIN; + + case NXT_EINTR: + nxt_log_debug(ev->log, "recvmsg(%d) interrupted", ev->fd); + continue; + + default: + nxt_log_error(NXT_LOG_CRIT, ev->log, + "recvmsg(%d, %p, %ui) failed %E", + ev->fd, fd, niob, err); + return NXT_ERROR; + } + } +} + + +#if (NXT_HAVE_MSGHDR_MSG_CONTROL) + +/* + * Linux, FreeBSD, Solaris X/Open sockets, + * MacOSX, NetBSD, AIX, HP-UX X/Open sockets. + */ + +static ssize_t +nxt_sendmsg(nxt_socket_t s, nxt_fd_t fd, nxt_iobuf_t *iob, nxt_uint_t niob) +{ + struct msghdr msg; + union { + struct cmsghdr cm; + char space[CMSG_SPACE(sizeof(int))]; + } cmsg; + + msg.msg_name = NULL; + msg.msg_namelen = 0; + msg.msg_iov = iob; + msg.msg_iovlen = niob; + /* Flags are cleared just to suppress valgrind warning. */ + msg.msg_flags = 0; + + if (fd != -1) { + msg.msg_control = (caddr_t) &cmsg; + msg.msg_controllen = sizeof(cmsg); + + cmsg.cm.cmsg_len = CMSG_LEN(sizeof(int)); + cmsg.cm.cmsg_level = SOL_SOCKET; + cmsg.cm.cmsg_type = SCM_RIGHTS; + + /* + * nxt_memcpy() is used instead of simple + * *(int *) CMSG_DATA(&cmsg.cm) = fd; + * because GCC 4.4 with -O2/3/s optimization may issue a warning: + * dereferencing type-punned pointer will break strict-aliasing rules + * + * Fortunately, GCC with -O1 compiles this nxt_memcpy() + * in the same simple assignment as in the code above. + */ + nxt_memcpy(CMSG_DATA(&cmsg.cm), &fd, sizeof(int)); + + } else { + msg.msg_control = NULL; + msg.msg_controllen = 0; + } + + return sendmsg(s, &msg, 0); +} + + +static ssize_t +nxt_recvmsg(nxt_socket_t s, nxt_fd_t *fd, nxt_iobuf_t *iob, nxt_uint_t niob) +{ + ssize_t n; + struct msghdr msg; + union { + struct cmsghdr cm; + char space[CMSG_SPACE(sizeof(int))]; + } cmsg; + + msg.msg_name = NULL; + msg.msg_namelen = 0; + msg.msg_iov = iob; + msg.msg_iovlen = niob; + msg.msg_control = (caddr_t) &cmsg; + msg.msg_controllen = sizeof(cmsg); + + *fd = -1; + + n = recvmsg(s, &msg, 0); + + if (n > 0 + && cmsg.cm.cmsg_len == CMSG_LEN(sizeof(int)) + && cmsg.cm.cmsg_level == SOL_SOCKET + && cmsg.cm.cmsg_type == SCM_RIGHTS) + { + /* (*fd) = *(int *) CMSG_DATA(&cmsg.cm); */ + nxt_memcpy(fd, CMSG_DATA(&cmsg.cm), sizeof(int)); + } + + return n; +} + +#else + +/* Solaris 4.3BSD sockets. */ + +static ssize_t +nxt_sendmsg(nxt_socket_t s, nxt_fd_t fd, nxt_iobuf_t *iob, nxt_uint_t niob) +{ + struct msghdr msg; + + msg.msg_name = NULL; + msg.msg_namelen = 0; + msg.msg_iov = iob; + msg.msg_iovlen = niob; + + if (fd != -1) { + msg.msg_accrights = (caddr_t) &fd; + msg.msg_accrightslen = sizeof(int); + + } else { + msg.msg_accrights = NULL; + msg.msg_accrightslen = 0; + } + + return sendmsg(s, &msg, 0); +} + + +static ssize_t +nxt_recvmsg(nxt_socket_t s, nxt_fd_t *fd, nxt_iobuf_t *iob, nxt_uint_t niob) +{ + struct msghdr msg; + + *fd = -1; + + msg.msg_name = NULL; + msg.msg_namelen = 0; + msg.msg_iov = iob; + msg.msg_iovlen = niob; + msg.msg_accrights = (caddr_t) fd; + msg.msg_accrightslen = sizeof(int); + + return recvmsg(s, &msg, 0); +} + +#endif |