cosmopolitan/libc/sock/sendmsg.c
Justine Tunney 2046c0d2ae Make improvements
- Expand redbean UNIX module
- Expand redbean documentation
- Ensure Lua copyright is embedded in binary
- Increase the PATH_MAX limit especially on NT
- Use column major sorting for linenoise completions
- Fix some suboptimalities in redbean's new UNIX API
- Figured out right flags for Multics newline in raw mode
2022-04-24 10:06:05 -07:00

98 lines
4.6 KiB
C

/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
│vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8 :vi│
╞══════════════════════════════════════════════════════════════════════════════╡
│ Copyright 2020 Justine Alexandra Roberts Tunney │
│ │
│ Permission to use, copy, modify, and/or distribute this software for │
│ any purpose with or without fee is hereby granted, provided that the │
│ above copyright notice and this permission notice appear in all copies. │
│ │
│ THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL │
│ WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED │
│ WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE │
│ AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL │
│ DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR │
│ PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER │
│ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR │
│ PERFORMANCE OF THIS SOFTWARE. │
╚─────────────────────────────────────────────────────────────────────────────*/
#include "libc/assert.h"
#include "libc/calls/internal.h"
#include "libc/calls/strace.internal.h"
#include "libc/calls/struct/iovec.h"
#include "libc/dce.h"
#include "libc/intrin/asan.internal.h"
#include "libc/intrin/kprintf.h"
#include "libc/sock/internal.h"
#include "libc/sock/sock.h"
#include "libc/str/str.h"
#include "libc/sysv/errfuns.h"
/**
* Sends a message on a socket.
*
* @param fd is the file descriptor returned by socket()
* @param msg is a pointer to a struct msghdr containing all the required
* parameters (the destination address, buffers, ...)
* @param flags MSG_OOB, MSG_DONTROUTE, MSG_PARTIAL, MSG_NOSIGNAL, etc.
* @return number of bytes transmitted, or -1 w/ errno
* @error EINTR, EHOSTUNREACH, ECONNRESET (UDP ICMP Port Unreachable),
* EPIPE (if MSG_NOSIGNAL), EMSGSIZE, ENOTSOCK, EFAULT, etc.
* @asyncsignalsafe
* @restartable (unless SO_RCVTIMEO)
*/
ssize_t sendmsg(int fd, const struct msghdr *msg, int flags) {
int64_t rc;
char addr2[128];
struct msghdr msg2;
if (IsAsan() && !__asan_is_valid_msghdr(msg)) {
rc = efault();
} else if (!IsWindows()) {
if (IsBsd() && msg->msg_name) {
/* An optional address is provided, convert it to the BSD form */
if (msg->msg_namelen <= sizeof(addr2)) {
memcpy(&addr2[0], msg->msg_name, msg->msg_namelen);
sockaddr2bsd(&addr2[0]);
/* Copy all of msg (except for msg_name) into the new ephemeral local */
memcpy(&msg2, msg, sizeof(msg2));
msg2.msg_name = &addr2[0];
rc = sys_sendmsg(fd, &msg2, flags);
} else {
rc = einval();
}
}
/* else do the syscall */
rc = sys_sendmsg(fd, msg, flags);
} else if (__isfdopen(fd)) {
if (msg->msg_control) {
rc = einval(); /* control msg not supported */
} else if (__isfdkind(fd, kFdSocket)) {
rc = sys_sendto_nt(fd, msg->msg_iov, msg->msg_iovlen, flags,
msg->msg_name, msg->msg_namelen);
} else if (__isfdkind(fd, kFdFile)) {
rc = sys_write_nt(fd, msg->msg_iov, msg->msg_iovlen, -1);
} else {
rc = enotsock();
}
} else {
rc = ebadf();
}
#if defined(SYSDEBUG) && _DATATRACE
if (__strace > 0) {
if (!msg || (rc == -1 && errno == EFAULT)) {
DATATRACE("sendmsg(%d, %p, %#x) → %'ld% m", fd, msg, flags, rc);
} else {
kprintf(STRACE_PROLOGUE "sendmsg(%d, {");
if (msg->msg_namelen)
kprintf(".name=%#.*hhs, ", msg->msg_namelen, msg->msg_name);
if (msg->msg_controllen)
kprintf(".control=%#.*hhs, ", msg->msg_controllen, msg->msg_control);
if (msg->msg_flags) kprintf(".flags=%#x, ", msg->msg_flags);
kprintf(".iov=", fd);
__strace_iov(msg->msg_iov, msg->msg_iovlen, rc != -1 ? rc : 0);
kprintf("}, %#x) → %'ld% m\n", flags, rc);
}
}
#endif
return rc;
}