mirror of
https://github.com/curl/curl.git
synced 2024-11-27 05:50:21 +08:00
1ad49feb71
- Removed from global_init since it isn't thread-safe. The symbol will still remain to not break compiles, it just won't have any effect going forward. - make the internals NOT loop on EINTR (the opposite from previously). It only risks returning from the select/poll/wait functions early, and that should be risk-free. Closes #4840
499 lines
14 KiB
C
499 lines
14 KiB
C
/***************************************************************************
|
|
* _ _ ____ _
|
|
* Project ___| | | | _ \| |
|
|
* / __| | | | |_) | |
|
|
* | (__| |_| | _ <| |___
|
|
* \___|\___/|_| \_\_____|
|
|
*
|
|
* Copyright (C) 1998 - 2020, Daniel Stenberg, <daniel@haxx.se>, et al.
|
|
*
|
|
* This software is licensed as described in the file COPYING, which
|
|
* you should have received as part of this distribution. The terms
|
|
* are also available at https://curl.haxx.se/docs/copyright.html.
|
|
*
|
|
* You may opt to use, copy, modify, merge, publish, distribute and/or sell
|
|
* copies of the Software, and permit persons to whom the Software is
|
|
* furnished to do so, under the terms of the COPYING file.
|
|
*
|
|
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
|
|
* KIND, either express or implied.
|
|
*
|
|
***************************************************************************/
|
|
|
|
#include "curl_setup.h"
|
|
|
|
#ifdef HAVE_SYS_SELECT_H
|
|
#include <sys/select.h>
|
|
#endif
|
|
|
|
#if !defined(HAVE_SELECT) && !defined(HAVE_POLL_FINE)
|
|
#error "We can't compile without select() or poll() support."
|
|
#endif
|
|
|
|
#if defined(__BEOS__) && !defined(__HAIKU__)
|
|
/* BeOS has FD_SET defined in socket.h */
|
|
#include <socket.h>
|
|
#endif
|
|
|
|
#ifdef MSDOS
|
|
#include <dos.h> /* delay() */
|
|
#endif
|
|
|
|
#ifdef __VXWORKS__
|
|
#include <strings.h> /* bzero() in FD_SET */
|
|
#endif
|
|
|
|
#include <curl/curl.h>
|
|
|
|
#include "urldata.h"
|
|
#include "connect.h"
|
|
#include "select.h"
|
|
#include "warnless.h"
|
|
|
|
/* Convenience local macros */
|
|
#define ELAPSED_MS() (int)Curl_timediff(Curl_now(), initial_tv)
|
|
|
|
/*
|
|
* Internal function used for waiting a specific amount of ms
|
|
* in Curl_socket_check() and Curl_poll() when no file descriptor
|
|
* is provided to wait on, just being used to delay execution.
|
|
* WinSock select() and poll() timeout mechanisms need a valid
|
|
* socket descriptor in a not null file descriptor set to work.
|
|
* Waiting indefinitely with this function is not allowed, a
|
|
* zero or negative timeout value will return immediately.
|
|
* Timeout resolution, accuracy, as well as maximum supported
|
|
* value is system dependent, neither factor is a citical issue
|
|
* for the intended use of this function in the library.
|
|
*
|
|
* Return values:
|
|
* -1 = system call error, invalid timeout value, or interrupted
|
|
* 0 = specified timeout has elapsed
|
|
*/
|
|
int Curl_wait_ms(int timeout_ms)
|
|
{
|
|
int r = 0;
|
|
|
|
if(!timeout_ms)
|
|
return 0;
|
|
if(timeout_ms < 0) {
|
|
SET_SOCKERRNO(EINVAL);
|
|
return -1;
|
|
}
|
|
#if defined(MSDOS)
|
|
delay(timeout_ms);
|
|
#elif defined(USE_WINSOCK)
|
|
Sleep(timeout_ms);
|
|
#else
|
|
#if defined(HAVE_POLL_FINE)
|
|
r = poll(NULL, 0, timeout_ms);
|
|
#else
|
|
{
|
|
struct timeval pending_tv;
|
|
pending_tv.tv_sec = timeout_ms / 1000;
|
|
pending_tv.tv_usec = (timeout_ms % 1000) * 1000;
|
|
r = select(0, NULL, NULL, NULL, &pending_tv);
|
|
}
|
|
#endif /* HAVE_POLL_FINE */
|
|
#endif /* USE_WINSOCK */
|
|
if(r)
|
|
r = -1;
|
|
return r;
|
|
}
|
|
|
|
/*
|
|
* Wait for read or write events on a set of file descriptors. It uses poll()
|
|
* when a fine poll() is available, in order to avoid limits with FD_SETSIZE,
|
|
* otherwise select() is used. An error is returned if select() is being used
|
|
* and a file descriptor is too large for FD_SETSIZE.
|
|
*
|
|
* A negative timeout value makes this function wait indefinitely,
|
|
* unless no valid file descriptor is given, when this happens the
|
|
* negative timeout is ignored and the function times out immediately.
|
|
*
|
|
* Return values:
|
|
* -1 = system call error or fd >= FD_SETSIZE
|
|
* 0 = timeout
|
|
* [bitmask] = action as described below
|
|
*
|
|
* CURL_CSELECT_IN - first socket is readable
|
|
* CURL_CSELECT_IN2 - second socket is readable
|
|
* CURL_CSELECT_OUT - write socket is writable
|
|
* CURL_CSELECT_ERR - an error condition occurred
|
|
*/
|
|
int Curl_socket_check(curl_socket_t readfd0, /* two sockets to read from */
|
|
curl_socket_t readfd1,
|
|
curl_socket_t writefd, /* socket to write to */
|
|
time_t timeout_ms) /* milliseconds to wait */
|
|
{
|
|
#ifdef HAVE_POLL_FINE
|
|
struct pollfd pfd[3];
|
|
int num;
|
|
#else
|
|
struct timeval pending_tv;
|
|
struct timeval *ptimeout;
|
|
fd_set fds_read;
|
|
fd_set fds_write;
|
|
fd_set fds_err;
|
|
curl_socket_t maxfd;
|
|
#endif
|
|
int pending_ms = 0;
|
|
int r;
|
|
int ret;
|
|
|
|
#if SIZEOF_TIME_T != SIZEOF_INT
|
|
/* wrap-around precaution */
|
|
if(timeout_ms >= INT_MAX)
|
|
timeout_ms = INT_MAX;
|
|
#endif
|
|
|
|
if((readfd0 == CURL_SOCKET_BAD) && (readfd1 == CURL_SOCKET_BAD) &&
|
|
(writefd == CURL_SOCKET_BAD)) {
|
|
/* no sockets, just wait */
|
|
r = Curl_wait_ms((int)timeout_ms);
|
|
return r;
|
|
}
|
|
|
|
/* Avoid initial timestamp, avoid Curl_now() call, when elapsed
|
|
time in this function does not need to be measured. This happens
|
|
when function is called with a zero timeout or a negative timeout
|
|
value indicating a blocking call should be performed. */
|
|
|
|
if(timeout_ms > 0) {
|
|
pending_ms = (int)timeout_ms;
|
|
}
|
|
|
|
#ifdef HAVE_POLL_FINE
|
|
|
|
num = 0;
|
|
if(readfd0 != CURL_SOCKET_BAD) {
|
|
pfd[num].fd = readfd0;
|
|
pfd[num].events = POLLRDNORM|POLLIN|POLLRDBAND|POLLPRI;
|
|
pfd[num].revents = 0;
|
|
num++;
|
|
}
|
|
if(readfd1 != CURL_SOCKET_BAD) {
|
|
pfd[num].fd = readfd1;
|
|
pfd[num].events = POLLRDNORM|POLLIN|POLLRDBAND|POLLPRI;
|
|
pfd[num].revents = 0;
|
|
num++;
|
|
}
|
|
if(writefd != CURL_SOCKET_BAD) {
|
|
pfd[num].fd = writefd;
|
|
pfd[num].events = POLLWRNORM|POLLOUT;
|
|
pfd[num].revents = 0;
|
|
num++;
|
|
}
|
|
|
|
if(timeout_ms < 0)
|
|
pending_ms = -1;
|
|
else if(!timeout_ms)
|
|
pending_ms = 0;
|
|
r = poll(pfd, num, pending_ms);
|
|
|
|
if(r < 0)
|
|
return -1;
|
|
if(r == 0)
|
|
return 0;
|
|
|
|
ret = 0;
|
|
num = 0;
|
|
if(readfd0 != CURL_SOCKET_BAD) {
|
|
if(pfd[num].revents & (POLLRDNORM|POLLIN|POLLERR|POLLHUP))
|
|
ret |= CURL_CSELECT_IN;
|
|
if(pfd[num].revents & (POLLRDBAND|POLLPRI|POLLNVAL))
|
|
ret |= CURL_CSELECT_ERR;
|
|
num++;
|
|
}
|
|
if(readfd1 != CURL_SOCKET_BAD) {
|
|
if(pfd[num].revents & (POLLRDNORM|POLLIN|POLLERR|POLLHUP))
|
|
ret |= CURL_CSELECT_IN2;
|
|
if(pfd[num].revents & (POLLRDBAND|POLLPRI|POLLNVAL))
|
|
ret |= CURL_CSELECT_ERR;
|
|
num++;
|
|
}
|
|
if(writefd != CURL_SOCKET_BAD) {
|
|
if(pfd[num].revents & (POLLWRNORM|POLLOUT))
|
|
ret |= CURL_CSELECT_OUT;
|
|
if(pfd[num].revents & (POLLERR|POLLHUP|POLLNVAL))
|
|
ret |= CURL_CSELECT_ERR;
|
|
}
|
|
|
|
return ret;
|
|
|
|
#else /* HAVE_POLL_FINE */
|
|
|
|
FD_ZERO(&fds_err);
|
|
maxfd = (curl_socket_t)-1;
|
|
|
|
FD_ZERO(&fds_read);
|
|
if(readfd0 != CURL_SOCKET_BAD) {
|
|
VERIFY_SOCK(readfd0);
|
|
FD_SET(readfd0, &fds_read);
|
|
FD_SET(readfd0, &fds_err);
|
|
maxfd = readfd0;
|
|
}
|
|
if(readfd1 != CURL_SOCKET_BAD) {
|
|
VERIFY_SOCK(readfd1);
|
|
FD_SET(readfd1, &fds_read);
|
|
FD_SET(readfd1, &fds_err);
|
|
if(readfd1 > maxfd)
|
|
maxfd = readfd1;
|
|
}
|
|
|
|
FD_ZERO(&fds_write);
|
|
if(writefd != CURL_SOCKET_BAD) {
|
|
VERIFY_SOCK(writefd);
|
|
FD_SET(writefd, &fds_write);
|
|
FD_SET(writefd, &fds_err);
|
|
if(writefd > maxfd)
|
|
maxfd = writefd;
|
|
}
|
|
|
|
ptimeout = (timeout_ms < 0) ? NULL : &pending_tv;
|
|
|
|
if(timeout_ms > 0) {
|
|
pending_tv.tv_sec = pending_ms / 1000;
|
|
pending_tv.tv_usec = (pending_ms % 1000) * 1000;
|
|
}
|
|
else if(!timeout_ms) {
|
|
pending_tv.tv_sec = 0;
|
|
pending_tv.tv_usec = 0;
|
|
}
|
|
|
|
/* WinSock select() must not be called with an fd_set that contains zero
|
|
fd flags, or it will return WSAEINVAL. But, it also can't be called
|
|
with no fd_sets at all! From the documentation:
|
|
|
|
Any two of the parameters, readfds, writefds, or exceptfds, can be
|
|
given as null. At least one must be non-null, and any non-null
|
|
descriptor set must contain at least one handle to a socket.
|
|
|
|
We know that we have at least one bit set in at least two fd_sets in
|
|
this case, but we may have no bits set in either fds_read or fd_write,
|
|
so check for that and handle it. Luckily, with WinSock, we can _also_
|
|
ask how many bits are set on an fd_set.
|
|
|
|
It is unclear why WinSock doesn't just handle this for us instead of
|
|
calling this an error.
|
|
|
|
Note also that WinSock ignores the first argument, so we don't worry
|
|
about the fact that maxfd is computed incorrectly with WinSock (since
|
|
curl_socket_t is unsigned in such cases and thus -1 is the largest
|
|
value).
|
|
*/
|
|
#ifdef USE_WINSOCK
|
|
r = select((int)maxfd + 1,
|
|
fds_read.fd_count ? &fds_read : NULL,
|
|
fds_write.fd_count ? &fds_write : NULL,
|
|
&fds_err, ptimeout);
|
|
#else
|
|
r = select((int)maxfd + 1, &fds_read, &fds_write, &fds_err, ptimeout);
|
|
#endif
|
|
|
|
if(r < 0)
|
|
return -1;
|
|
if(r == 0)
|
|
return 0;
|
|
|
|
ret = 0;
|
|
if(readfd0 != CURL_SOCKET_BAD) {
|
|
if(FD_ISSET(readfd0, &fds_read))
|
|
ret |= CURL_CSELECT_IN;
|
|
if(FD_ISSET(readfd0, &fds_err))
|
|
ret |= CURL_CSELECT_ERR;
|
|
}
|
|
if(readfd1 != CURL_SOCKET_BAD) {
|
|
if(FD_ISSET(readfd1, &fds_read))
|
|
ret |= CURL_CSELECT_IN2;
|
|
if(FD_ISSET(readfd1, &fds_err))
|
|
ret |= CURL_CSELECT_ERR;
|
|
}
|
|
if(writefd != CURL_SOCKET_BAD) {
|
|
if(FD_ISSET(writefd, &fds_write))
|
|
ret |= CURL_CSELECT_OUT;
|
|
if(FD_ISSET(writefd, &fds_err))
|
|
ret |= CURL_CSELECT_ERR;
|
|
}
|
|
|
|
return ret;
|
|
|
|
#endif /* HAVE_POLL_FINE */
|
|
|
|
}
|
|
|
|
/*
|
|
* This is a wrapper around poll(). If poll() does not exist, then
|
|
* select() is used instead. An error is returned if select() is
|
|
* being used and a file descriptor is too large for FD_SETSIZE.
|
|
* A negative timeout value makes this function wait indefinitely,
|
|
* unless no valid file descriptor is given, when this happens the
|
|
* negative timeout is ignored and the function times out immediately.
|
|
*
|
|
* Return values:
|
|
* -1 = system call error or fd >= FD_SETSIZE
|
|
* 0 = timeout
|
|
* N = number of structures with non zero revent fields
|
|
*/
|
|
int Curl_poll(struct pollfd ufds[], unsigned int nfds, int timeout_ms)
|
|
{
|
|
#ifndef HAVE_POLL_FINE
|
|
struct timeval pending_tv;
|
|
struct timeval *ptimeout;
|
|
fd_set fds_read;
|
|
fd_set fds_write;
|
|
fd_set fds_err;
|
|
curl_socket_t maxfd;
|
|
#endif
|
|
bool fds_none = TRUE;
|
|
unsigned int i;
|
|
int pending_ms = 0;
|
|
int r;
|
|
|
|
if(ufds) {
|
|
for(i = 0; i < nfds; i++) {
|
|
if(ufds[i].fd != CURL_SOCKET_BAD) {
|
|
fds_none = FALSE;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
if(fds_none) {
|
|
r = Curl_wait_ms(timeout_ms);
|
|
return r;
|
|
}
|
|
|
|
/* Avoid initial timestamp, avoid Curl_now() call, when elapsed
|
|
time in this function does not need to be measured. This happens
|
|
when function is called with a zero timeout or a negative timeout
|
|
value indicating a blocking call should be performed. */
|
|
|
|
if(timeout_ms > 0) {
|
|
pending_ms = timeout_ms;
|
|
}
|
|
|
|
#ifdef HAVE_POLL_FINE
|
|
|
|
if(timeout_ms < 0)
|
|
pending_ms = -1;
|
|
else if(!timeout_ms)
|
|
pending_ms = 0;
|
|
r = poll(ufds, nfds, pending_ms);
|
|
|
|
if(r < 0)
|
|
return -1;
|
|
if(r == 0)
|
|
return 0;
|
|
|
|
for(i = 0; i < nfds; i++) {
|
|
if(ufds[i].fd == CURL_SOCKET_BAD)
|
|
continue;
|
|
if(ufds[i].revents & POLLHUP)
|
|
ufds[i].revents |= POLLIN;
|
|
if(ufds[i].revents & POLLERR)
|
|
ufds[i].revents |= (POLLIN|POLLOUT);
|
|
}
|
|
|
|
#else /* HAVE_POLL_FINE */
|
|
|
|
FD_ZERO(&fds_read);
|
|
FD_ZERO(&fds_write);
|
|
FD_ZERO(&fds_err);
|
|
maxfd = (curl_socket_t)-1;
|
|
|
|
for(i = 0; i < nfds; i++) {
|
|
ufds[i].revents = 0;
|
|
if(ufds[i].fd == CURL_SOCKET_BAD)
|
|
continue;
|
|
VERIFY_SOCK(ufds[i].fd);
|
|
if(ufds[i].events & (POLLIN|POLLOUT|POLLPRI|
|
|
POLLRDNORM|POLLWRNORM|POLLRDBAND)) {
|
|
if(ufds[i].fd > maxfd)
|
|
maxfd = ufds[i].fd;
|
|
if(ufds[i].events & (POLLRDNORM|POLLIN))
|
|
FD_SET(ufds[i].fd, &fds_read);
|
|
if(ufds[i].events & (POLLWRNORM|POLLOUT))
|
|
FD_SET(ufds[i].fd, &fds_write);
|
|
if(ufds[i].events & (POLLRDBAND|POLLPRI))
|
|
FD_SET(ufds[i].fd, &fds_err);
|
|
}
|
|
}
|
|
|
|
#ifdef USE_WINSOCK
|
|
/* WinSock select() can't handle zero events. See the comment about this in
|
|
Curl_check_socket(). */
|
|
if(fds_read.fd_count == 0 && fds_write.fd_count == 0
|
|
&& fds_err.fd_count == 0) {
|
|
r = Curl_wait_ms(timeout_ms);
|
|
return r;
|
|
}
|
|
#endif
|
|
|
|
ptimeout = (timeout_ms < 0) ? NULL : &pending_tv;
|
|
|
|
if(timeout_ms > 0) {
|
|
pending_tv.tv_sec = pending_ms / 1000;
|
|
pending_tv.tv_usec = (pending_ms % 1000) * 1000;
|
|
}
|
|
else if(!timeout_ms) {
|
|
pending_tv.tv_sec = 0;
|
|
pending_tv.tv_usec = 0;
|
|
}
|
|
|
|
#ifdef USE_WINSOCK
|
|
r = select((int)maxfd + 1,
|
|
/* WinSock select() can't handle fd_sets with zero bits set, so
|
|
don't give it such arguments. See the comment about this in
|
|
Curl_check_socket().
|
|
*/
|
|
fds_read.fd_count ? &fds_read : NULL,
|
|
fds_write.fd_count ? &fds_write : NULL,
|
|
fds_err.fd_count ? &fds_err : NULL, ptimeout);
|
|
#else
|
|
r = select((int)maxfd + 1, &fds_read, &fds_write, &fds_err, ptimeout);
|
|
#endif
|
|
|
|
if(r < 0)
|
|
return -1;
|
|
if(r == 0)
|
|
return 0;
|
|
|
|
r = 0;
|
|
for(i = 0; i < nfds; i++) {
|
|
ufds[i].revents = 0;
|
|
if(ufds[i].fd == CURL_SOCKET_BAD)
|
|
continue;
|
|
if(FD_ISSET(ufds[i].fd, &fds_read))
|
|
ufds[i].revents |= POLLIN;
|
|
if(FD_ISSET(ufds[i].fd, &fds_write))
|
|
ufds[i].revents |= POLLOUT;
|
|
if(FD_ISSET(ufds[i].fd, &fds_err))
|
|
ufds[i].revents |= POLLPRI;
|
|
if(ufds[i].revents != 0)
|
|
r++;
|
|
}
|
|
|
|
#endif /* HAVE_POLL_FINE */
|
|
|
|
return r;
|
|
}
|
|
|
|
#ifdef TPF
|
|
/*
|
|
* This is a replacement for select() on the TPF platform.
|
|
* It is used whenever libcurl calls select().
|
|
* The call below to tpf_process_signals() is required because
|
|
* TPF's select calls are not signal interruptible.
|
|
*
|
|
* Return values are the same as select's.
|
|
*/
|
|
int tpf_select_libcurl(int maxfds, fd_set *reads, fd_set *writes,
|
|
fd_set *excepts, struct timeval *tv)
|
|
{
|
|
int rc;
|
|
|
|
rc = tpf_select_bsd(maxfds, reads, writes, excepts, tv);
|
|
tpf_process_signals();
|
|
return rc;
|
|
}
|
|
#endif /* TPF */
|