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-rw-r--r--lib/select.c220
1 files changed, 146 insertions, 74 deletions
diff --git a/lib/select.c b/lib/select.c
index e6882da7..24dc5fd7 100644
--- a/lib/select.c
+++ b/lib/select.c
@@ -5,7 +5,7 @@
* | (__| |_| | _ <| |___
* \___|\___/|_| \_\_____|
*
- * Copyright (C) 1998 - 2009, Daniel Stenberg, <daniel@haxx.se>, et al.
+ * Copyright (C) 1998 - 2015, 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
@@ -20,14 +20,11 @@
*
***************************************************************************/
-#include "setup.h"
+#include "curl_setup.h"
#ifdef HAVE_SYS_SELECT_H
#include <sys/select.h>
#endif
-#ifdef HAVE_SYS_TIME_H
-#include <sys/time.h>
-#endif
#if !defined(HAVE_SELECT) && !defined(HAVE_POLL_FINE)
#error "We can't compile without select() or poll() support."
@@ -42,35 +39,23 @@
#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"
-
-/* Winsock and TPF sockets are not in range [0..FD_SETSIZE-1] */
-
-#if defined(USE_WINSOCK) || defined(TPF)
-#define VERIFY_SOCK(x) do { } while(0)
-#else
-#define VALID_SOCK(s) (((s) >= 0) && ((s) < FD_SETSIZE))
-#define VERIFY_SOCK(x) do { \
- if(!VALID_SOCK(x)) { \
- SET_SOCKERRNO(EINVAL); \
- return -1; \
- } \
-} while(0)
-#endif
+#include "warnless.h"
/* Convenience local macros */
#define elapsed_ms (int)curlx_tvdiff(curlx_tvnow(), initial_tv)
-#ifdef CURL_ACKNOWLEDGE_EINTR
-#define error_not_EINTR (1)
-#else
-#define error_not_EINTR (error != EINTR)
-#endif
+int Curl_ack_eintr = 0;
+#define error_not_EINTR (Curl_ack_eintr || error != EINTR)
/*
* Internal function used for waiting a specific amount of ms
@@ -83,16 +68,12 @@
* 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.
- * On non-DOS and non-Winsock platforms, when compiled with
- * CURL_ACKNOWLEDGE_EINTR defined, EINTR condition is honored
- * and function might exit early without awaiting full timeout,
- * otherwise EINTR will be ignored and full timeout will elapse.
*
* Return values:
* -1 = system call error, invalid timeout value, or interrupted
* 0 = specified timeout has elapsed
*/
-static int wait_ms(int timeout_ms)
+int Curl_wait_ms(int timeout_ms)
{
#if !defined(MSDOS) && !defined(USE_WINSOCK)
#ifndef HAVE_POLL_FINE
@@ -131,8 +112,10 @@ static int wait_ms(int timeout_ms)
if(error && error_not_EINTR)
break;
pending_ms = timeout_ms - elapsed_ms;
- if(pending_ms <= 0)
+ if(pending_ms <= 0) {
+ r = 0; /* Simulate a "call timed out" case */
break;
+ }
} while(r == -1);
#endif /* USE_WINSOCK */
if(r)
@@ -141,28 +124,32 @@ static int wait_ms(int timeout_ms)
}
/*
- * This is an internal function used for waiting for read or write
- * events on a pair 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.
+ * 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,
* unles no valid file descriptor is given, when this happens the
* negative timeout is ignored and the function times out immediately.
- * When compiled with CURL_ACKNOWLEDGE_EINTR defined, EINTR condition
- * is honored and function might exit early without awaiting timeout,
- * otherwise EINTR will be ignored.
*
* Return values:
* -1 = system call error or fd >= FD_SETSIZE
* 0 = timeout
- * CURL_CSELECT_IN | CURL_CSELECT_OUT | CURL_CSELECT_ERR
+ * [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_ready(curl_socket_t readfd, curl_socket_t writefd,
- int timeout_ms)
+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 */
+ long timeout_ms) /* milliseconds to wait */
{
#ifdef HAVE_POLL_FINE
- struct pollfd pfd[2];
+ struct pollfd pfd[3];
int num;
#else
struct timeval pending_tv;
@@ -172,14 +159,16 @@ int Curl_socket_ready(curl_socket_t readfd, curl_socket_t writefd,
fd_set fds_err;
curl_socket_t maxfd;
#endif
- struct timeval initial_tv = {0,0};
+ struct timeval initial_tv = {0, 0};
int pending_ms = 0;
int error;
int r;
int ret;
- if((readfd == CURL_SOCKET_BAD) && (writefd == CURL_SOCKET_BAD)) {
- r = wait_ms(timeout_ms);
+ 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;
}
@@ -189,15 +178,21 @@ int Curl_socket_ready(curl_socket_t readfd, curl_socket_t writefd,
value indicating a blocking call should be performed. */
if(timeout_ms > 0) {
- pending_ms = timeout_ms;
+ pending_ms = (int)timeout_ms;
initial_tv = curlx_tvnow();
}
#ifdef HAVE_POLL_FINE
num = 0;
- if(readfd != CURL_SOCKET_BAD) {
- pfd[num].fd = readfd;
+ 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++;
@@ -221,9 +216,11 @@ int Curl_socket_ready(curl_socket_t readfd, curl_socket_t writefd,
if(error && error_not_EINTR)
break;
if(timeout_ms > 0) {
- pending_ms = timeout_ms - elapsed_ms;
- if(pending_ms <= 0)
+ pending_ms = (int)(timeout_ms - elapsed_ms);
+ if(pending_ms <= 0) {
+ r = 0; /* Simulate a "call timed out" case */
break;
+ }
}
} while(r == -1);
@@ -234,13 +231,20 @@ int Curl_socket_ready(curl_socket_t readfd, curl_socket_t writefd,
ret = 0;
num = 0;
- if(readfd != CURL_SOCKET_BAD) {
+ 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;
@@ -256,11 +260,18 @@ int Curl_socket_ready(curl_socket_t readfd, curl_socket_t writefd,
maxfd = (curl_socket_t)-1;
FD_ZERO(&fds_read);
- if(readfd != CURL_SOCKET_BAD) {
- VERIFY_SOCK(readfd);
- FD_SET(readfd, &fds_read);
- FD_SET(readfd, &fds_err);
- maxfd = readfd;
+ 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);
@@ -283,7 +294,37 @@ int Curl_socket_ready(curl_socket_t readfd, curl_socket_t writefd,
pending_tv.tv_sec = 0;
pending_tv.tv_usec = 0;
}
- r = select((int)maxfd + 1, &fds_read, &fds_write, &fds_err, ptimeout);
+
+ /* 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).
+ */
+ r = select((int)maxfd + 1,
+#ifndef USE_WINSOCK
+ &fds_read,
+ &fds_write,
+#else
+ fds_read.fd_count ? &fds_read : NULL,
+ fds_write.fd_count ? &fds_write : NULL,
+#endif
+ &fds_err, ptimeout);
if(r != -1)
break;
error = SOCKERRNO;
@@ -291,8 +332,10 @@ int Curl_socket_ready(curl_socket_t readfd, curl_socket_t writefd,
break;
if(timeout_ms > 0) {
pending_ms = timeout_ms - elapsed_ms;
- if(pending_ms <= 0)
+ if(pending_ms <= 0) {
+ r = 0; /* Simulate a "call timed out" case */
break;
+ }
}
} while(r == -1);
@@ -302,10 +345,16 @@ int Curl_socket_ready(curl_socket_t readfd, curl_socket_t writefd,
return 0;
ret = 0;
- if(readfd != CURL_SOCKET_BAD) {
- if(FD_ISSET(readfd, &fds_read))
+ if(readfd0 != CURL_SOCKET_BAD) {
+ if(FD_ISSET(readfd0, &fds_read))
ret |= CURL_CSELECT_IN;
- if(FD_ISSET(readfd, &fds_err))
+ 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) {
@@ -328,9 +377,6 @@ int Curl_socket_ready(curl_socket_t readfd, curl_socket_t writefd,
* A negative timeout value makes this function wait indefinitely,
* unles no valid file descriptor is given, when this happens the
* negative timeout is ignored and the function times out immediately.
- * When compiled with CURL_ACKNOWLEDGE_EINTR defined, EINTR condition
- * is honored and function might exit early without awaiting timeout,
- * otherwise EINTR will be ignored.
*
* Return values:
* -1 = system call error or fd >= FD_SETSIZE
@@ -347,7 +393,7 @@ int Curl_poll(struct pollfd ufds[], unsigned int nfds, int timeout_ms)
fd_set fds_err;
curl_socket_t maxfd;
#endif
- struct timeval initial_tv = {0,0};
+ struct timeval initial_tv = {0, 0};
bool fds_none = TRUE;
unsigned int i;
int pending_ms = 0;
@@ -355,7 +401,7 @@ int Curl_poll(struct pollfd ufds[], unsigned int nfds, int timeout_ms)
int r;
if(ufds) {
- for (i = 0; i < nfds; i++) {
+ for(i = 0; i < nfds; i++) {
if(ufds[i].fd != CURL_SOCKET_BAD) {
fds_none = FALSE;
break;
@@ -363,7 +409,7 @@ int Curl_poll(struct pollfd ufds[], unsigned int nfds, int timeout_ms)
}
}
if(fds_none) {
- r = wait_ms(timeout_ms);
+ r = Curl_wait_ms(timeout_ms);
return r;
}
@@ -392,8 +438,10 @@ int Curl_poll(struct pollfd ufds[], unsigned int nfds, int timeout_ms)
break;
if(timeout_ms > 0) {
pending_ms = timeout_ms - elapsed_ms;
- if(pending_ms <= 0)
+ if(pending_ms <= 0) {
+ r = 0; /* Simulate a "call timed out" case */
break;
+ }
}
} while(r == -1);
@@ -402,7 +450,7 @@ int Curl_poll(struct pollfd ufds[], unsigned int nfds, int timeout_ms)
if(r == 0)
return 0;
- for (i = 0; i < nfds; i++) {
+ for(i = 0; i < nfds; i++) {
if(ufds[i].fd == CURL_SOCKET_BAD)
continue;
if(ufds[i].revents & POLLHUP)
@@ -418,7 +466,7 @@ int Curl_poll(struct pollfd ufds[], unsigned int nfds, int timeout_ms)
FD_ZERO(&fds_err);
maxfd = (curl_socket_t)-1;
- for (i = 0; i < nfds; i++) {
+ for(i = 0; i < nfds; i++) {
ufds[i].revents = 0;
if(ufds[i].fd == CURL_SOCKET_BAD)
continue;
@@ -436,6 +484,16 @@ int Curl_poll(struct pollfd ufds[], unsigned int nfds, int timeout_ms)
}
}
+#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;
do {
@@ -447,7 +505,19 @@ int Curl_poll(struct pollfd ufds[], unsigned int nfds, int timeout_ms)
pending_tv.tv_sec = 0;
pending_tv.tv_usec = 0;
}
- r = select((int)maxfd + 1, &fds_read, &fds_write, &fds_err, ptimeout);
+ r = select((int)maxfd + 1,
+#ifndef USE_WINSOCK
+ &fds_read, &fds_write, &fds_err,
+#else
+ /* 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,
+#endif
+ ptimeout);
if(r != -1)
break;
error = SOCKERRNO;
@@ -455,8 +525,10 @@ int Curl_poll(struct pollfd ufds[], unsigned int nfds, int timeout_ms)
break;
if(timeout_ms > 0) {
pending_ms = timeout_ms - elapsed_ms;
- if(pending_ms <= 0)
+ if(pending_ms <= 0) {
+ r = 0; /* Simulate a "call timed out" case */
break;
+ }
}
} while(r == -1);
@@ -466,7 +538,7 @@ int Curl_poll(struct pollfd ufds[], unsigned int nfds, int timeout_ms)
return 0;
r = 0;
- for (i = 0; i < nfds; i++) {
+ for(i = 0; i < nfds; i++) {
ufds[i].revents = 0;
if(ufds[i].fd == CURL_SOCKET_BAD)
continue;
@@ -501,6 +573,6 @@ int tpf_select_libcurl(int maxfds, fd_set* reads, fd_set* writes,
rc = tpf_select_bsd(maxfds, reads, writes, excepts, tv);
tpf_process_signals();
- return(rc);
+ return rc;
}
#endif /* TPF */
generated by cgit v1.2.3 (git 2.25.1) at 2024-05-29 02:49:07 +0000