Fix for interface issues (Bug 571909 <571909@bugs.launchpad.net>)

[m6w6/libmemcached] / libmemcached / io.c

diff --git a/libmemcached/io.c b/libmemcached/io.c
index 070af6b19462d9056f7a3181ba4944e26ae7b9cf..30a2a1a4921396a967b71bd92bda79ec57ce3bb6 100644 (file)
--- a/libmemcached/io.c
+++ b/libmemcached/io.c
@@ -32,8 +32,15 @@ static memcached_return_t io_wait(memcached_server_write_instance_st ptr,
   };
   int error;
 
-  unlikely (read_or_write == MEM_WRITE) /* write */
+  if (read_or_write == MEM_WRITE) /* write */
+  {
     fds.events= POLLOUT;
+    WATCHPOINT_SET(ptr->io_wait_count.write++);
+  }
+  else
+  {
+    WATCHPOINT_SET(ptr->io_wait_count.read++);
+  }
 
   /*
    ** We are going to block on write, but at least on Solaris we might block
@@ -55,37 +62,50 @@ static memcached_return_t io_wait(memcached_server_write_instance_st ptr,
     timeout= -1;
 
   size_t loop_max= 5;
-  while (--loop_max)
+  while (--loop_max) // While loop is for ERESTART or EINTR
   {
     error= poll(&fds, 1, timeout);
 
     switch (error)
     {
-    case 1:
+    case 1: // Success!
+      WATCHPOINT_IF_LABELED_NUMBER(read_or_write && loop_max < 4, "read() times we had to loop, decremented down from 5", loop_max);
+      WATCHPOINT_IF_LABELED_NUMBER(!read_or_write && loop_max < 4, "write() times we had to loop, decremented down from 5", loop_max);
+
       return MEMCACHED_SUCCESS;
-    case 0:
-      continue;
+    case 0: // Timeout occured, we let the while() loop do its thing.
+      return MEMCACHED_TIMEOUT;
     default:
       WATCHPOINT_ERRNO(errno);
+      switch (errno)
       {
-        switch (errno)
+#ifdef TARGET_OS_LINUX
+      case ERESTART:
+#endif
+      case EINTR:
+        break;
+      default:
+        if (fds.revents & POLLERR)
         {
-        default:
-          ptr->cached_errno= error;
-          memcached_quit_server(ptr, true);
-
-          return MEMCACHED_FAILURE;
+          int err;
+          socklen_t len= sizeof (err);
+          (void)getsockopt(ptr->fd, SOL_SOCKET, SO_ERROR, &err, &len);
+          ptr->cached_errno= (err == 0) ? errno : err;
+        }
+        else
+        {
+          ptr->cached_errno= errno;
         }
+        memcached_quit_server(ptr, true);
+
+        return MEMCACHED_FAILURE;
       }
     }
   }
 
-  if (loop_max == 0 && error == 0)
-    return MEMCACHED_TIMEOUT;
-
   /* Imposssible for anything other then -1 */
   WATCHPOINT_ASSERT(error == -1);
-  ptr->cached_errno= error;
+  ptr->cached_errno= errno;
   memcached_quit_server(ptr, true);
 
   return MEMCACHED_FAILURE;
@@ -257,11 +277,13 @@ memcached_return_t memcached_io_read(memcached_server_write_instance_st ptr,
       {
         data_read= read(ptr->fd, ptr->read_buffer, MEMCACHED_MAX_BUFFER);
         if (data_read > 0)
+        {
           break;
+        }
         else if (data_read == -1)
         {
           ptr->cached_errno= errno;
-          memcached_return_t rc= MEMCACHED_UNKNOWN_READ_FAILURE;
+          memcached_return_t rc= MEMCACHED_ERRNO;
           switch (errno)
           {
           case EAGAIN:
@@ -292,6 +314,7 @@ memcached_return_t memcached_io_read(memcached_server_write_instance_st ptr,
             for blocking I/O we do not return 0 and for non-blocking case
             it will return EGAIN if data is not immediatly available.
           */
+          WATCHPOINT_STRING("We had a zero length read()");
           memcached_quit_server(ptr, true);
           *nread= -1;
           return MEMCACHED_UNKNOWN_READ_FAILURE;
@@ -589,6 +612,7 @@ static ssize_t io_flush(memcached_server_write_instance_st ptr,
     {
       ptr->cached_errno= errno;
       WATCHPOINT_ERRNO(errno);
+      WATCHPOINT_NUMBER(errno);
       switch (errno)
       {
       case ENOBUFS: