socks: Fix blocking timeout logic
- Document in Curl_timeleft's comment block that returning 0 signals no
timeout (ie there's infinite time left).
- Fix SOCKS' Curl_blockread_all for the case when no timeout was set.
Prior to this change if the timeout had a value of 0 and that was passed
to SOCKET_READABLE it would return right away instead of blocking. That
was likely because it was not well understood that when Curl_timeleft
returns 0 it is not a timeout of 0 ms but actually means no timeout.
Ref: https://github.com/curl/curl/pull/5214#issuecomment-612512360
Closes https://github.com/curl/curl/pull/5220
diff --git a/lib/connect.c b/lib/connect.c
index 54c5f9e..421f904 100644
--- a/lib/connect.c
+++ b/lib/connect.c
@@ -171,7 +171,8 @@
/*
* Curl_timeleft() returns the amount of milliseconds left allowed for the
- * transfer/connection. If the value is negative, the timeout time has already
+ * transfer/connection. If the value is 0, there's no timeout (ie there's
+ * infinite time left). If the value is negative, the timeout time has already
* elapsed.
*
* The start time is stored in progress.t_startsingle - as set with
diff --git a/lib/socks.c b/lib/socks.c
index 5dd8363..dfd944e 100644
--- a/lib/socks.c
+++ b/lib/socks.c
@@ -62,15 +62,15 @@
int result;
*n = 0;
for(;;) {
- timediff_t timeleft = Curl_timeleft(conn->data, NULL, TRUE);
- if(timeleft < 0) {
+ timediff_t timeout_ms = Curl_timeleft(conn->data, NULL, TRUE);
+ if(timeout_ms < 0) {
/* we already got the timeout */
result = CURLE_OPERATION_TIMEDOUT;
break;
}
- if(timeleft > TIME_T_MAX)
- timeleft = TIME_T_MAX;
- if(SOCKET_READABLE(sockfd, (time_t)timeleft) <= 0) {
+ if(!timeout_ms || timeout_ms > TIME_T_MAX)
+ timeout_ms = TIME_T_MAX;
+ if(SOCKET_READABLE(sockfd, (time_t)timeout_ms) <= 0) {
result = ~CURLE_OK;
break;
}
