Revert "multi: implement wait using winsock events"

This reverts commit 8bc25c590e530de87595d1bb3577f699eb1309b9.

That commit (from #5397) introduced a regression in 7.71.0.

Reported-by: tmkk on github
Fixes #5631
Closes #5632

2 files changed, 4 insertions, 122 deletions

diff --git a/lib/multi.c b/lib/multi.c
index b106c9495..249e3607b 100644
--- a/lib/multi.c
+++ b/lib/multi.c
@@ -374,11 +374,6 @@ struct Curl_multi *Curl_multi_handle(int hashsize, /* socket hash */
   multi->max_concurrent_streams = 100;
   multi->ipv6_works = Curl_ipv6works(NULL);
 
-#ifdef USE_WINSOCK
-  multi->wsa_event = WSACreateEvent();
-  if(multi->wsa_event == WSA_INVALID_EVENT)
-    goto error;
-#else
 #ifdef ENABLE_WAKEUP
   if(Curl_socketpair(AF_UNIX, SOCK_STREAM, 0, multi->wakeup_pair) < 0) {
     multi->wakeup_pair[0] = CURL_SOCKET_BAD;
@@ -392,7 +387,6 @@ struct Curl_multi *Curl_multi_handle(int hashsize, /* socket hash */
     multi->wakeup_pair[1] = CURL_SOCKET_BAD;
   }
 #endif
-#endif
 
   return multi;
 
@@ -1073,15 +1067,11 @@ static CURLMcode Curl_multi_wait(struct Curl_multi *multi,
   unsigned int i;
   unsigned int nfds = 0;
   unsigned int curlfds;
+  bool ufds_malloc = FALSE;
   long timeout_internal;
   int retcode = 0;
-#ifndef USE_WINSOCK
   struct pollfd a_few_on_stack[NUM_POLLS_ON_STACK];
   struct pollfd *ufds = &a_few_on_stack[0];
-  bool ufds_malloc = FALSE;
-#else
-  DEBUGASSERT(multi->wsa_event != WSA_INVALID_EVENT);
-#endif
 
   if(!GOOD_MULTI_HANDLE(multi))
     return CURLM_BAD_HANDLE;
@@ -1127,16 +1117,11 @@ static CURLMcode Curl_multi_wait(struct Curl_multi *multi,
   nfds += extra_nfds; /* add the externally provided ones */
 
 #ifdef ENABLE_WAKEUP
-#ifdef USE_WINSOCK
-  if(use_wakeup) {
-#else
   if(use_wakeup && multi->wakeup_pair[0] != CURL_SOCKET_BAD) {
-#endif
     ++nfds;
   }
 #endif
 
-#ifndef USE_WINSOCK
   if(nfds > NUM_POLLS_ON_STACK) {
     /* 'nfds' is a 32 bit value and 'struct pollfd' is typically 8 bytes
        big, so at 2^29 sockets this value might wrap. When a process gets
@@ -1147,9 +1132,7 @@ static CURLMcode Curl_multi_wait(struct Curl_multi *multi,
       return CURLM_OUT_OF_MEMORY;
     ufds_malloc = TRUE;
   }
-
   nfds = 0;
-#endif
 
   /* only do the second loop if we found descriptors in the first stage run
      above */
@@ -1162,36 +1145,22 @@ static CURLMcode Curl_multi_wait(struct Curl_multi *multi,
 
       for(i = 0; i< MAX_SOCKSPEREASYHANDLE; i++) {
         curl_socket_t s = CURL_SOCKET_BAD;
-#ifdef USE_WINSOCK
-        long mask = 0;
-#endif
+
         if(bitmap & GETSOCK_READSOCK(i)) {
-#ifdef USE_WINSOCK
-          mask |= FD_READ;
-#else
           ufds[nfds].fd = sockbunch[i];
           ufds[nfds].events = POLLIN;
           ++nfds;
-#endif
           s = sockbunch[i];
         }
         if(bitmap & GETSOCK_WRITESOCK(i)) {
-#ifdef USE_WINSOCK
-          mask |= FD_WRITE;
-#else
           ufds[nfds].fd = sockbunch[i];
           ufds[nfds].events = POLLOUT;
           ++nfds;
-#endif
           s = sockbunch[i];
         }
         if(s == CURL_SOCKET_BAD) {
           break;
         }
-#ifdef USE_WINSOCK
-        if(WSAEventSelect(s, multi->wsa_event, mask) != 0)
-          return CURLM_INTERNAL_ERROR;
-#endif
       }
 
       data = data->next; /* check next handle */
@@ -1200,17 +1169,6 @@ static CURLMcode Curl_multi_wait(struct Curl_multi *multi,
 
   /* Add external file descriptions from poll-like struct curl_waitfd */
   for(i = 0; i < extra_nfds; i++) {
-#ifdef USE_WINSOCK
-    long events = 0;
-    if(extra_fds[i].events & CURL_WAIT_POLLIN)
-      events |= FD_READ;
-    if(extra_fds[i].events & CURL_WAIT_POLLPRI)
-      events |= FD_OOB;
-    if(extra_fds[i].events & CURL_WAIT_POLLOUT)
-      events |= FD_WRITE;
-    if(WSAEventSelect(extra_fds[i].fd, multi->wsa_event, events) != 0)
-      return CURLM_INTERNAL_ERROR;
-#else
     ufds[nfds].fd = extra_fds[i].fd;
     ufds[nfds].events = 0;
     if(extra_fds[i].events & CURL_WAIT_POLLIN)
@@ -1220,61 +1178,28 @@ static CURLMcode Curl_multi_wait(struct Curl_multi *multi,
     if(extra_fds[i].events & CURL_WAIT_POLLOUT)
       ufds[nfds].events |= POLLOUT;
     ++nfds;
-#endif
   }
 
 #ifdef ENABLE_WAKEUP
-#ifndef USE_WINSOCK
   if(use_wakeup && multi->wakeup_pair[0] != CURL_SOCKET_BAD) {
     ufds[nfds].fd = multi->wakeup_pair[0];
     ufds[nfds].events = POLLIN;
     ++nfds;
   }
 #endif
-#endif
 
   if(nfds) {
     int pollrc;
     /* wait... */
-#ifdef USE_WINSOCK
-    DWORD waitrc = WSAWaitForMultipleEvents(1, &multi->wsa_event, FALSE,
-                                            timeout_ms, FALSE);
-    /* WSA_WAIT_EVENT_0 is 0, so waitrc >= WSA_WAIT_EVENT_0 warns */
-    if(waitrc == WSA_WAIT_EVENT_0)
-      pollrc = 1;
-    else
-      pollrc = -1;
-#else
     pollrc = Curl_poll(ufds, nfds, timeout_ms);
-#endif
 
     if(pollrc > 0) {
-#ifdef USE_WINSOCK
-      retcode = 0;
-#else
       retcode = pollrc;
-#endif
       /* copy revents results from the poll to the curl_multi_wait poll
          struct, the bit values of the actual underlying poll() implementation
          may not be the same as the ones in the public libcurl API! */
       for(i = 0; i < extra_nfds; i++) {
         unsigned short mask = 0;
-#ifdef USE_WINSOCK
-        WSANETWORKEVENTS events = {0};
-        if(WSAEnumNetworkEvents(extra_fds[i].fd, multi->wsa_event,
-                                &events) == 0) {
-          if(events.lNetworkEvents & FD_READ)
-            mask |= CURL_WAIT_POLLIN;
-          if(events.lNetworkEvents & FD_WRITE)
-            mask |= CURL_WAIT_POLLOUT;
-          if(events.lNetworkEvents & FD_OOB)
-            mask |= CURL_WAIT_POLLPRI;
-
-          if(events.lNetworkEvents != 0)
-            retcode++;
-        }
-        WSAEventSelect(extra_fds[i].fd, multi->wsa_event, 0);
-#else
         unsigned r = ufds[curlfds + i].revents;
 
         if(r & POLLIN)
@@ -1283,39 +1208,10 @@ static CURLMcode Curl_multi_wait(struct Curl_multi *multi,
           mask |= CURL_WAIT_POLLOUT;
         if(r & POLLPRI)
           mask |= CURL_WAIT_POLLPRI;
-#endif
 
         extra_fds[i].revents = mask;
       }
 
-#ifdef USE_WINSOCK
-      /* Count up all our own sockets that had activity,
-         and remove them from the event. */
-      if(curlfds) {
-        data = multi->easyp;
-        while(data) {
-          bitmap = multi_getsock(data, sockbunch);
-
-          for(i = 0; i < MAX_SOCKSPEREASYHANDLE; i++) {
-            if(bitmap & (GETSOCK_READSOCK(i) | GETSOCK_WRITESOCK(i))) {
-              WSANETWORKEVENTS events = {0};
-              if(WSAEnumNetworkEvents(sockbunch[i], multi->wsa_event,
-                                      &events) == 0) {
-                if(events.lNetworkEvents != 0)
-                  retcode++;
-              }
-              WSAEventSelect(sockbunch[i], multi->wsa_event, 0);
-            }
-            else
-              break;
-          }
-
-          data = data->next;
-        }
-      }
-
-      WSAResetEvent(multi->wsa_event);
-#else
 #ifdef ENABLE_WAKEUP
       if(use_wakeup && multi->wakeup_pair[0] != CURL_SOCKET_BAD) {
         if(ufds[curlfds + extra_nfds].revents & POLLIN) {
@@ -1328,8 +1224,10 @@ static CURLMcode Curl_multi_wait(struct Curl_multi *multi,
                when there is no more data, breaking the loop. */
             nread = sread(multi->wakeup_pair[0], buf, sizeof(buf));
             if(nread <= 0) {
+#ifndef USE_WINSOCK
               if(nread < 0 && EINTR == SOCKERRNO)
                 continue;
+#endif
               break;
             }
           }
@@ -1338,14 +1236,11 @@ static CURLMcode Curl_multi_wait(struct Curl_multi *multi,
         }
       }
 #endif
-#endif
     }
   }
 
-#ifndef USE_WINSOCK
   if(ufds_malloc)
     free(ufds);
-#endif
   if(ret)
     *ret = retcode;
   if(!extrawait || nfds)
@@ -1400,10 +1295,6 @@ CURLMcode curl_multi_wakeup(struct Curl_multi *multi)
     return CURLM_BAD_HANDLE;
 
 #ifdef ENABLE_WAKEUP
-#ifdef USE_WINSOCK
-  if(WSASetEvent(multi->wsa_event))
-    return CURLM_OK;
-#else
   /* the wakeup_pair variable is only written during init and cleanup,
      making it safe to access from another thread after the init part
      and before cleanup */
@@ -1437,7 +1328,6 @@ CURLMcode curl_multi_wakeup(struct Curl_multi *multi)
     }
   }
 #endif
-#endif
   return CURLM_WAKEUP_FAILURE;
 }
 
@@ -2596,14 +2486,10 @@ CURLMcode curl_multi_cleanup(struct Curl_multi *multi)
     Curl_hash_destroy(&multi->hostcache);
     Curl_psl_destroy(&multi->psl);
 
-#ifdef USE_WINSOCK
-    WSACloseEvent(multi->wsa_event);
-#else
 #ifdef ENABLE_WAKEUP
     sclose(multi->wakeup_pair[0]);
     sclose(multi->wakeup_pair[1]);
 #endif
-#endif
     free(multi);
 
     return CURLM_OK;
diff --git a/lib/multihandle.h b/lib/multihandle.h
index 94bbad77a..91eca16c4 100644
--- a/lib/multihandle.h
+++ b/lib/multihandle.h
@@ -138,14 +138,10 @@ struct Curl_multi {
                                     previous callback */
   unsigned int max_concurrent_streams;
 
-#ifdef USE_WINSOCK
-  WSAEVENT wsa_event; /* winsock event used for waits */
-#else
 #ifdef ENABLE_WAKEUP
   curl_socket_t wakeup_pair[2]; /* socketpair() used for wakeup
                                    0 is used for read, 1 is used for write */
 #endif
-#endif
   /* multiplexing wanted */
   bool multiplexing;
   bool recheckstate; /* see Curl_multi_connchanged */