- Save one call to curlx_tvnow(), which calls gettimeofday(), in each of
Curl_socket_ready(), Curl_poll() and Curl_select() when these are called
with a zero timeout or a timeout value indicating a blocking call should
be performed.
These unnecessary calls to gettimeofday() got introduced in 7.16.2 when
fixing 'timeout would restart when signal caught while awaiting socket
events' on 20 March 2007.
- Move some loop breaking logic from the while clause into the loop,
avoiding compiler warning 'assignment within conditional expression'
diff --git a/CHANGES b/CHANGES
index 94726eb..3fb9c2c 100644
--- a/CHANGES
+++ b/CHANGES
@@ -6,6 +6,12 @@
Changelog
+Yang Tse (20 April 2007)
+- Save one call to curlx_tvnow(), which calls gettimeofday(), in each of
+ Curl_socket_ready(), Curl_poll() and Curl_select() when these are called
+ with a zero timeout or a timeout value indicating a blocking call should
+ be performed.
+
Daniel S (18 April 2007)
- James Housley made SFTP uploads use libssh2's non-blocking API
diff --git a/RELEASE-NOTES b/RELEASE-NOTES
index 5dee28b..2c0c69c 100644
--- a/RELEASE-NOTES
+++ b/RELEASE-NOTES
@@ -22,6 +22,7 @@
for a host which was supposed not to exist.
o test suite SSL certificate works better with newer stunnel
o internal progress meter update frequency back to once per second
+ o avoid some unnecessary calls to function gettimeofday
This release includes the following known bugs:
diff --git a/lib/select.c b/lib/select.c
index 30aece4..9d75e77 100644
--- a/lib/select.c
+++ b/lib/select.c
@@ -76,12 +76,12 @@
#define elapsed_ms (int)curlx_tvdiff(curlx_tvnow(), initial_tv)
#ifdef CURL_ACKNOWLEDGE_EINTR
-#define error_not_EINTR (error != EINTR)
+#define error_is_EINTR (error == EINTR)
#else
-#define error_not_EINTR (1)
+#define error_is_EINTR (0)
#endif
-#define SMALL_POLLNFDS 0X20
+#define SMALL_POLLNFDS 0x20
/*
* Internal function used for waiting a specific amount of ms
@@ -136,9 +136,15 @@
pending_tv.tv_usec = (pending_ms % 1000) * 1000;
r = select(0, NULL, NULL, NULL, &pending_tv);
#endif /* HAVE_POLL_FINE */
- } while ((r == -1) && (error = SOCKERRNO) &&
- (error != EINVAL) && error_not_EINTR &&
- ((pending_ms = timeout_ms - elapsed_ms) > 0));
+ if (r != -1)
+ break;
+ error = SOCKERRNO;
+ if ((error == EINVAL) || error_is_EINTR)
+ break;
+ pending_ms = timeout_ms - elapsed_ms;
+ if (pending_ms <= 0)
+ break;
+ } while (r == -1);
#endif /* USE_WINSOCK */
if (r)
r = -1;
@@ -188,8 +194,15 @@
return r;
}
- pending_ms = timeout_ms;
- initial_tv = curlx_tvnow();
+ /* Avoid initial timestamp, avoid gettimeofday() 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;
+ initial_tv = curlx_tvnow();
+ }
#ifdef HAVE_POLL_FINE
@@ -210,10 +223,20 @@
do {
if (timeout_ms < 0)
pending_ms = -1;
+ else if (!timeout_ms)
+ pending_ms = 0;
r = poll(pfd, num, pending_ms);
- } while ((r == -1) && (error = SOCKERRNO) &&
- (error != EINVAL) && error_not_EINTR &&
- ((timeout_ms < 0) || ((pending_ms = timeout_ms - elapsed_ms) > 0)));
+ if (r != -1)
+ break;
+ error = SOCKERRNO;
+ if ((error == EINVAL) || error_is_EINTR)
+ break;
+ if (timeout_ms > 0) {
+ pending_ms = timeout_ms - elapsed_ms;
+ if (pending_ms <= 0)
+ break;
+ }
+ } while (r == -1);
if (r < 0)
return -1;
@@ -263,14 +286,26 @@
ptimeout = (timeout_ms < 0) ? NULL : &pending_tv;
do {
- if (ptimeout) {
+ 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;
+ }
r = select((int)maxfd + 1, &fds_read, &fds_write, &fds_err, ptimeout);
- } while ((r == -1) && (error = SOCKERRNO) &&
- (error != EINVAL) && (error != EBADF) && error_not_EINTR &&
- ((timeout_ms < 0) || ((pending_ms = timeout_ms - elapsed_ms) > 0)));
+ if (r != -1)
+ break;
+ error = SOCKERRNO;
+ if ((error == EINVAL) || (error == EBADF) || error_is_EINTR)
+ break;
+ if (timeout_ms > 0) {
+ pending_ms = timeout_ms - elapsed_ms;
+ if (pending_ms <= 0)
+ break;
+ }
+ } while (r == -1);
if (r < 0)
return -1;
@@ -343,18 +378,35 @@
return r;
}
- pending_ms = timeout_ms;
- initial_tv = curlx_tvnow();
+ /* Avoid initial timestamp, avoid gettimeofday() 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;
+ initial_tv = curlx_tvnow();
+ }
#ifdef HAVE_POLL_FINE
do {
if (timeout_ms < 0)
pending_ms = -1;
+ else if (!timeout_ms)
+ pending_ms = 0;
r = poll(ufds, nfds, pending_ms);
- } while ((r == -1) && (error = SOCKERRNO) &&
- (error != EINVAL) && error_not_EINTR &&
- ((timeout_ms < 0) || ((pending_ms = timeout_ms - elapsed_ms) > 0)));
+ if (r != -1)
+ break;
+ error = SOCKERRNO;
+ if ((error == EINVAL) || error_is_EINTR)
+ break;
+ if (timeout_ms > 0) {
+ pending_ms = timeout_ms - elapsed_ms;
+ if (pending_ms <= 0)
+ break;
+ }
+ } while (r == -1);
#else /* HAVE_POLL_FINE */
@@ -384,14 +436,26 @@
ptimeout = (timeout_ms < 0) ? NULL : &pending_tv;
do {
- if (ptimeout) {
+ 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;
+ }
r = select((int)maxfd + 1, &fds_read, &fds_write, &fds_err, ptimeout);
- } while ((r == -1) && (error = SOCKERRNO) &&
- (error != EINVAL) && (error != EBADF) && error_not_EINTR &&
- ((timeout_ms < 0) || ((pending_ms = timeout_ms - elapsed_ms) > 0)));
+ if (r != -1)
+ break;
+ error = SOCKERRNO;
+ if ((error == EINVAL) || (error == EBADF) || error_is_EINTR)
+ break;
+ if (timeout_ms > 0) {
+ pending_ms = timeout_ms - elapsed_ms;
+ if (pending_ms <= 0)
+ break;
+ }
+ } while (r == -1);
if (r < 0)
return -1;
@@ -481,8 +545,16 @@
return r;
}
- pending_ms = timeout_ms;
- initial_tv = curlx_tvnow();
+ /* Avoid initial timestamp, avoid gettimeofday() call, when elapsed
+ time in this function does not need to be measured. This happens
+ when function is called with a zero timeout in the timeval struct
+ referenced argument or when a NULL pointer is received as timeval
+ reference indicating a blocking call should be performed. */
+
+ if (timeout_ms > 0) {
+ pending_ms = timeout_ms;
+ initial_tv = curlx_tvnow();
+ }
#ifdef HAVE_POLL_FINE
@@ -530,10 +602,20 @@
do {
if (timeout_ms < 0)
pending_ms = -1;
+ else if (!timeout_ms)
+ pending_ms = 0;
r = poll(poll_fds, poll_nfds, pending_ms);
- } while ((r == -1) && (error = SOCKERRNO) &&
- (error != EINVAL) && error_not_EINTR &&
- ((timeout_ms < 0) || ((pending_ms = timeout_ms - elapsed_ms) > 0)));
+ if (r != -1)
+ break;
+ error = SOCKERRNO;
+ if ((error == EINVAL) || error_is_EINTR)
+ break;
+ if (timeout_ms > 0) {
+ pending_ms = timeout_ms - elapsed_ms;
+ if (pending_ms <= 0)
+ break;
+ }
+ } while (r == -1);
if (r < 0)
ret = -1;
@@ -583,14 +665,26 @@
ptimeout = (timeout_ms < 0) ? NULL : &pending_tv;
do {
- if (ptimeout) {
+ 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;
+ }
r = select(nfds, fds_read, fds_write, fds_excep, ptimeout);
- } while ((r == -1) && (error = SOCKERRNO) &&
- (error != EINVAL) && (error != EBADF) && error_not_EINTR &&
- ((timeout_ms < 0) || ((pending_ms = timeout_ms - elapsed_ms) > 0)));
+ if (r != -1)
+ break;
+ error = SOCKERRNO;
+ if ((error == EINVAL) || (error == EBADF) || error_is_EINTR)
+ break;
+ if (timeout_ms > 0) {
+ pending_ms = timeout_ms - elapsed_ms;
+ if (pending_ms <= 0)
+ break;
+ }
+ } while (r == -1);
if (r < 0)
ret = -1;
