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socket: add support for socket() flags

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On start, check if the SOCK_CLOEXEC and SOCK_NONBLOCK flags are
supported in the socket() call and use them instead of fcntl() in order
to reduce the number of system calls required to send a client request.
This commit is contained in:
Miroslav Lichvar 2019-07-23 17:26:29 +02:00
parent 4d26cfc92b
commit 27fd751915
1 changed files with 47 additions and 3 deletions
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50
socket.c
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@ -82,6 +82,9 @@ struct MessageHeader {
static int initialised;
/* Flags supported by socket() */
static int socket_flags;
/* Arrays of Message and MessageHeader */
static ARR_Instance recv_messages;
static ARR_Instance recv_headers;
@ -140,12 +143,35 @@ domain_to_string(int domain)
/* ================================================== */
static int
check_socket_flag(int sock_flag, int fd_flag, int fs_flag)
{
int sock_fd, fd_flags, fs_flags;
sock_fd = socket(AF_INET, SOCK_DGRAM | sock_flag, 0);
if (sock_fd < 0)
return 0;
fd_flags = fcntl(sock_fd, F_GETFD);
fs_flags = fcntl(sock_fd, F_GETFL);
close(sock_fd);
if (fd_flags == -1 || (fd_flags & fd_flag) != fd_flag ||
fs_flags == -1 || (fs_flags & fs_flag) != fs_flag)
return 0;
return 1;
}
/* ================================================== */
static int
open_socket(int domain, int type, int flags)
{
int sock_fd;
sock_fd = socket(domain, type, 0);
sock_fd = socket(domain, type | socket_flags, 0);
if (sock_fd < 0) {
DEBUG_LOG("Could not open %s socket : %s",
@ -154,14 +180,22 @@ open_socket(int domain, int type, int flags)
}
/* Close the socket automatically on exec */
if (!UTI_FdSetCloexec(sock_fd)) {
if (
#ifdef SOCK_CLOEXEC
(socket_flags & SOCK_CLOEXEC) == 0 &&
#endif
!UTI_FdSetCloexec(sock_fd)) {
DEBUG_LOG("Could not set O_CLOEXEC : %s", strerror(errno));
close(sock_fd);
return INVALID_SOCK_FD;
}
/* Enable non-blocking mode */
if (fcntl(sock_fd, F_SETFL, O_NONBLOCK)) {
if (
#ifdef SOCK_NONBLOCK
(socket_flags & SOCK_NONBLOCK) == 0 &&
#endif
fcntl(sock_fd, F_SETFL, O_NONBLOCK)) {
DEBUG_LOG("Could not set O_NONBLOCK : %s", strerror(errno));
close(sock_fd);
return INVALID_SOCK_FD;
@ -943,6 +977,16 @@ SCK_Initialise(void)
priv_bind_function = NULL;
socket_flags = 0;
#ifdef SOCK_CLOEXEC
if (check_socket_flag(SOCK_CLOEXEC, FD_CLOEXEC, 0))
socket_flags |= SOCK_CLOEXEC;
#endif
#ifdef SOCK_NONBLOCK
if (check_socket_flag(SOCK_NONBLOCK, 0, O_NONBLOCK))
socket_flags |= SOCK_NONBLOCK;
#endif
initialised = 1;
}