multi: add curl_multi_wakeup()

This commit adds curl_multi_wakeup() which was previously in the TODO
list under the curl_multi_unblock name.

On some platforms and with some configurations this feature might not be
available or can fail, in these cases a new error code
(CURLM_WAKEUP_FAILURE) is returned from curl_multi_wakeup().

Fixes #4418
Closes #4608

1 files changed, 204 insertions, 0 deletions

diff --git a/tests/libtest/lib1565.c b/tests/libtest/lib1565.c
new file mode 100644
index 000000000..b2fa40aaa
--- /dev/null
+++ b/tests/libtest/lib1565.c
@@ -0,0 +1,204 @@
+/***************************************************************************
+ *                                  _   _ ____  _
+ *  Project                     ___| | | |  _ \| |
+ *                             / __| | | | |_) | |
+ *                            | (__| |_| |  _ <| |___
+ *                             \___|\___/|_| \_\_____|
+ *
+ * Copyright (C) 1998 - 2019, 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 "test.h"
+
+#include "testutil.h"
+#include "warnless.h"
+#include "memdebug.h"
+
+#ifdef HAVE_PTHREAD_H
+#include <pthread.h>
+#include <unistd.h>
+
+#define TEST_HANG_TIMEOUT 60 * 1000
+#define CONN_NUM 3
+#define TIME_BETWEEN_START_SECS 2
+
+static pthread_mutex_t lock = PTHREAD_MUTEX_INITIALIZER;
+static CURL *pending_handles[CONN_NUM];
+static int pending_num = 0;
+static int test_failure = 0;
+
+static CURLM *multi = NULL;
+static const char *url;
+
+static void *run_thread(void *ptr)
+{
+  CURL *easy = NULL;
+  int res = 0;
+  int i;
+
+  (void)ptr;
+
+  for(i = 0; i < CONN_NUM; i++) {
+    sleep(TIME_BETWEEN_START_SECS);
+
+    easy_init(easy);
+
+    easy_setopt(easy, CURLOPT_URL, url);
+    easy_setopt(easy, CURLOPT_VERBOSE, 0L);
+
+    pthread_mutex_lock(&lock);
+
+    if(test_failure) {
+      pthread_mutex_unlock(&lock);
+      goto test_cleanup;
+    }
+
+    pending_handles[pending_num] = easy;
+    pending_num++;
+    easy = NULL;
+
+    pthread_mutex_unlock(&lock);
+
+    multi_wakeup(multi);
+  }
+
+test_cleanup:
+
+  curl_easy_cleanup(easy);
+
+  pthread_mutex_lock(&lock);
+
+  if(!test_failure)
+    test_failure = res;
+
+  pthread_mutex_unlock(&lock);
+
+  return NULL;
+}
+
+int test(char *URL)
+{
+  int still_running;
+  int num;
+  int i;
+  int res = 0;
+  CURL *started_handles[CONN_NUM];
+  int started_num = 0;
+  int finished_num = 0;
+  pthread_t tid = 0;
+  struct CURLMsg *message;
+
+  start_test_timing();
+
+  global_init(CURL_GLOBAL_ALL);
+
+  multi_init(multi);
+
+  url = URL;
+
+  res = pthread_create(&tid, NULL, run_thread, NULL);
+  if(0 != res) {
+    fprintf(stderr, "%s:%d Couldn't create thread, errno %d\n",
+            __FILE__, __LINE__, res);
+    goto test_cleanup;
+  }
+
+  while(1) {
+    multi_perform(multi, &still_running);
+
+    abort_on_test_timeout();
+
+    while((message = curl_multi_info_read(multi, &num)) != NULL) {
+      if(message->msg == CURLMSG_DONE) {
+        res = message->data.result;
+        if(res)
+          goto test_cleanup;
+        multi_remove_handle(multi, message->easy_handle);
+        finished_num++;
+      }
+      else {
+        fprintf(stderr, "%s:%d Got an unexpected message from curl: %i\n",
+              __FILE__, __LINE__, (int)message->msg);
+        res = TEST_ERR_MAJOR_BAD;
+        goto test_cleanup;
+      }
+
+      abort_on_test_timeout();
+    }
+
+    if(CONN_NUM == finished_num)
+      break;
+
+    multi_poll(multi, NULL, 0, TEST_HANG_TIMEOUT, &num);
+
+    abort_on_test_timeout();
+
+    pthread_mutex_lock(&lock);
+
+    while(pending_num > 0) {
+      res_multi_add_handle(multi, pending_handles[pending_num - 1]);
+      if(res) {
+        pthread_mutex_unlock(&lock);
+        goto test_cleanup;
+      }
+
+      started_handles[started_num] = pending_handles[pending_num - 1];
+      started_num++;
+      pending_num--;
+    }
+
+    pthread_mutex_unlock(&lock);
+
+    abort_on_test_timeout();
+  }
+
+  if(CONN_NUM != started_num) {
+    fprintf(stderr, "%s:%d Not all connections started: %d of %d\n",
+            __FILE__, __LINE__, started_num, CONN_NUM);
+    goto test_cleanup;
+  }
+
+  if(CONN_NUM != finished_num) {
+    fprintf(stderr, "%s:%d Not all connections finished: %d of %d\n",
+            __FILE__, __LINE__, started_num, CONN_NUM);
+    goto test_cleanup;
+  }
+
+test_cleanup:
+
+  pthread_mutex_lock(&lock);
+  if(!test_failure)
+    test_failure = res;
+  pthread_mutex_unlock(&lock);
+
+  if(0 != tid)
+    pthread_join(tid, NULL);
+
+  curl_multi_cleanup(multi);
+  for(i = 0; i < pending_num; i++)
+    curl_easy_cleanup(pending_handles[i]);
+  for(i = 0; i < started_num; i++)
+    curl_easy_cleanup(started_handles[i]);
+  curl_global_cleanup();
+
+  return test_failure;
+}
+
+#else /* without pthread, this test doesn't work */
+int test(char *URL)
+{
+  (void)URL;
+  return 0;
+}
+#endif