X-Git-Url: https://git.m6w6.name/?a=blobdiff_plain;f=libmemcached%2Fio.cc;h=d0e6aaf6f10cb7942d574420b953ecf4dc7d90d6;hb=a28d1ecc082d9d08c4f59f071de9a43fbd08aee3;hp=538f15371688b593179946043db0ae27566d7431;hpb=651ddd54069f57b25c5fade3cfcd736c7e220e6d;p=m6w6%2Flibmemcached

diff --git a/libmemcached/io.cc b/libmemcached/io.cc
index 538f1537..d0e6aaf6 100644
--- a/libmemcached/io.cc
+++ b/libmemcached/io.cc
@@ -67,24 +67,27 @@ static bool repack_input_buffer(memcached_server_write_instance_st ptr)
   {
     do {
       /* Just try a single read to grab what's available */
-      ssize_t nr= recv(ptr->fd,
-                       ptr->read_ptr + ptr->read_data_length,
-                       MEMCACHED_MAX_BUFFER - ptr->read_data_length,
-                       MSG_DONTWAIT);
-
-      switch (nr)
+      ssize_t nr;
+      if ((nr= recv(ptr->fd,
+                    ptr->read_ptr + ptr->read_data_length,
+                    MEMCACHED_MAX_BUFFER - ptr->read_data_length,
+                    MSG_DONTWAIT)) <= 0)
       {
-      case SOCKET_ERROR:
+        if (nr == 0)
+        {
+          memcached_set_error(*ptr, MEMCACHED_CONNECTION_FAILURE, MEMCACHED_AT);
+        }
+        else
         {
           switch (get_socket_errno())
           {
           case EINTR:
             continue;
 
+#if EWOULDBLOCK != EAGAIN
           case EWOULDBLOCK:
-#ifdef USE_EAGAIN
-          case EAGAIN:
 #endif
+          case EAGAIN:
 #ifdef TARGET_OS_LINUX
           case ERESTART:
 #endif
@@ -94,24 +97,19 @@ static bool repack_input_buffer(memcached_server_write_instance_st ptr)
             memcached_set_errno(*ptr, get_socket_errno(), MEMCACHED_AT);
           }
         }
-        break;
 
-      case 0: // Shutdown on the socket has occurred
-        {
-          memcached_set_error(*ptr, MEMCACHED_CONNECTION_FAILURE, MEMCACHED_AT);
-        }
         break;
+      }
+      else // We read data, append to our read buffer
+      {
+        ptr->read_data_length+= size_t(nr);
+        ptr->read_buffer_length+= size_t(nr);
 
-      default:
-        {
-          ptr->read_data_length+= size_t(nr);
-          ptr->read_buffer_length+= size_t(nr);
-          return true;
-        }
-        break;
+        return true;
       }
-    } while (0);
+    } while (false);
   }
+
   return false;
 }
 
@@ -142,10 +140,8 @@ static bool process_input_buffer(memcached_server_write_instance_st ptr)
     memcached_set_processing_input((memcached_st *)ptr->root, true);
 
     char buffer[MEMCACHED_DEFAULT_COMMAND_SIZE];
-    memcached_return_t error;
     memcached_st *root= (memcached_st *)ptr->root;
-    error= memcached_response(ptr, buffer, sizeof(buffer),
-                              &root->result);
+    memcached_return_t error= memcached_response(ptr, buffer, sizeof(buffer), &root->result);
 
     memcached_set_processing_input(root, false);
 
@@ -155,7 +151,9 @@ static bool process_input_buffer(memcached_server_write_instance_st ptr)
       {
         error= (*cb.callback[x])(ptr->root, &root->result, cb.context);
         if (error != MEMCACHED_SUCCESS)
+        {
           break;
+        }
       }
 
       /* @todo what should I do with the error message??? */
@@ -170,20 +168,6 @@ static bool process_input_buffer(memcached_server_write_instance_st ptr)
 static memcached_return_t io_wait(memcached_server_write_instance_st ptr,
                                   const memc_read_or_write read_or_write)
 {
-  struct pollfd fds;
-  fds.fd= ptr->fd;
-  fds.events= POLLIN;
-
-  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
    ** on write if we haven't read anything from our input buffer..
@@ -194,80 +178,91 @@ static memcached_return_t io_wait(memcached_server_write_instance_st ptr,
  */
   if (read_or_write == MEM_WRITE)
   {
-    memcached_return_t rc= memcached_purge(ptr);
-    if (rc != MEMCACHED_SUCCESS && rc != MEMCACHED_STORED)
+    if (memcached_purge(ptr) == false)
     {
       return MEMCACHED_FAILURE;
     }
   }
 
+  struct pollfd fds;
+  fds.fd= ptr->fd;
+  fds.events= POLLIN;
+  fds.revents= 0;
+
+  if (read_or_write == MEM_WRITE) /* write */
+  {
+    fds.events= POLLOUT;
+    ptr->io_wait_count.write++;
+  }
+  else
+  {
+    ptr->io_wait_count.read++;
+  }
+
   if (ptr->root->poll_timeout == 0) // Mimic 0 causes timeout behavior (not all platforms do this)
   {
+    ptr->io_wait_count.timeouts++;
     return memcached_set_error(*ptr, MEMCACHED_TIMEOUT, MEMCACHED_AT);
   }
 
+  int local_errno;
   size_t loop_max= 5;
   while (--loop_max) // While loop is for ERESTART or EINTR
   {
+    int active_fd= poll(&fds, 1, ptr->root->poll_timeout);
 
-    int error= poll(&fds, 1, ptr->root->poll_timeout);
-    switch (error)
+    if (active_fd >= 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);
-
+      assert_msg(active_fd == 1 , "poll() returned an unexpected value");
       return MEMCACHED_SUCCESS;
-
-    case 0: // Timeout occured, we let the while() loop do its thing.
+    }
+    else if (active_fd == 0)
+    {
+      ptr->io_wait_count.timeouts++;
       return memcached_set_error(*ptr, MEMCACHED_TIMEOUT, MEMCACHED_AT);
+    }
 
-    default:
-      WATCHPOINT_ERRNO(get_socket_errno());
-      switch (get_socket_errno())
-      {
+    // Only an error should result in this code being called.
+    local_errno= get_socket_errno(); // We cache in case memcached_quit_server() modifies errno
+    assert_msg(active_fd == -1 , "poll() returned an unexpected value");
+    switch (local_errno)
+    {
 #ifdef TARGET_OS_LINUX
-      case ERESTART:
+    case ERESTART:
 #endif
-      case EINTR:
-        break;
+    case EINTR:
+      continue;
 
-      case EFAULT:
-      case ENOMEM:
-        return memcached_set_error(*ptr, MEMCACHED_MEMORY_ALLOCATION_FAILURE, MEMCACHED_AT);
+    case EFAULT:
+    case ENOMEM:
+      return memcached_set_error(*ptr, MEMCACHED_MEMORY_ALLOCATION_FAILURE, MEMCACHED_AT);
 
-      case EINVAL:
-        return memcached_set_error(*ptr, MEMCACHED_MEMORY_ALLOCATION_FAILURE, MEMCACHED_AT, memcached_literal_param("RLIMIT_NOFILE exceeded, or if OSX the timeout value was invalid"));
+    case EINVAL:
+      return memcached_set_error(*ptr, MEMCACHED_MEMORY_ALLOCATION_FAILURE, MEMCACHED_AT, memcached_literal_param("RLIMIT_NOFILE exceeded, or if OSX the timeout value was invalid"));
 
-      default:
-        if (fds.revents & POLLERR)
+    default:
+      if (fds.revents & POLLERR)
+      {
+        int err;
+        socklen_t len= sizeof (err);
+        if (getsockopt(ptr->fd, SOL_SOCKET, SO_ERROR, &err, &len) == 0)
         {
-          int err;
-          socklen_t len= sizeof (err);
-          if (getsockopt(ptr->fd, SOL_SOCKET, SO_ERROR, &err, &len) == 0)
+          if (err == 0) // treat this as EINTR
           {
-            if (err == 0)
-            {
-              continue;
-            }
-            errno= err;
+            continue;
           }
+          local_errno= err;
         }
-        else
-        {
-          memcached_set_errno(*ptr, get_socket_errno(), MEMCACHED_AT);
-        }
-        int local_errno= get_socket_errno(); // We cache in case memcached_quit_server() modifies errno
-        memcached_quit_server(ptr, true);
-
-        return memcached_set_errno(*ptr, local_errno, MEMCACHED_AT);
       }
+      break;
     }
+
+    break; // should only occur from poll error
   }
 
   memcached_quit_server(ptr, true);
 
-  return memcached_set_errno(*ptr, get_socket_errno(), MEMCACHED_AT);
+  return memcached_set_errno(*ptr, local_errno, MEMCACHED_AT);
 }
 
 static bool io_flush(memcached_server_write_instance_st ptr,
@@ -280,11 +275,9 @@ static bool io_flush(memcached_server_write_instance_st ptr,
    ** in the purge function to avoid duplicating the logic..
  */
   {
-    memcached_return_t rc;
     WATCHPOINT_ASSERT(ptr->fd != INVALID_SOCKET);
-    rc= memcached_purge(ptr);
 
-    if (rc != MEMCACHED_SUCCESS && rc != MEMCACHED_STORED)
+    if (memcached_purge(ptr) == false)
     {
       return false;
     }
@@ -308,20 +301,11 @@ static bool io_flush(memcached_server_write_instance_st ptr,
     WATCHPOINT_ASSERT(ptr->fd != INVALID_SOCKET);
     WATCHPOINT_ASSERT(write_length > 0);
 
-    ssize_t sent_length= 0;
-    WATCHPOINT_ASSERT(ptr->fd != INVALID_SOCKET);
-    if (with_flush)
-    {
-      sent_length= ::send(ptr->fd, local_write_ptr, write_length, MSG_NOSIGNAL|MSG_DONTWAIT);
-    }
-    else
-    {
-      sent_length= ::send(ptr->fd, local_write_ptr, write_length, MSG_NOSIGNAL|MSG_DONTWAIT|MSG_MORE);
-    }
+    int flags= with_flush ? MSG_NOSIGNAL|MSG_DONTWAIT : MSG_NOSIGNAL|MSG_DONTWAIT|MSG_MORE;
+    ssize_t sent_length= ::send(ptr->fd, local_write_ptr, write_length, flags);
 
     if (sent_length == SOCKET_ERROR)
     {
-      memcached_set_errno(*ptr, get_socket_errno(), MEMCACHED_AT);
 #if 0 // @todo I should look at why we hit this bit of code hard frequently
       WATCHPOINT_ERRNO(get_socket_errno());
       WATCHPOINT_NUMBER(get_socket_errno());
@@ -330,10 +314,11 @@ static bool io_flush(memcached_server_write_instance_st ptr,
       {
       case ENOBUFS:
         continue;
+
+#if EWOULDBLOCK != EAGAIN
       case EWOULDBLOCK:
-#ifdef USE_EAGAIN
-      case EAGAIN:
 #endif
+      case EAGAIN:
         {
           /*
            * We may be blocked on write because the input buffer
@@ -353,7 +338,6 @@ static bool io_flush(memcached_server_write_instance_st ptr,
           }
           else if (rc == MEMCACHED_TIMEOUT)
           {
-            error= memcached_set_error(*ptr, MEMCACHED_TIMEOUT, MEMCACHED_AT);
             return false;
           }
 
@@ -378,14 +362,7 @@ static bool io_flush(memcached_server_write_instance_st ptr,
   }
 
   WATCHPOINT_ASSERT(write_length == 0);
-  if (memcached_is_udp(ptr->root))
-  {
-    ptr->write_buffer_offset= UDP_DATAGRAM_HEADER_LENGTH;
-  }
-  else
-  {
-    ptr->write_buffer_offset= 0;
-  }
+  ptr->write_buffer_offset= 0;
 
   return true;
 }
@@ -412,7 +389,7 @@ memcached_return_t memcached_io_read(memcached_server_write_instance_st ptr,
 
   while (length)
   {
-    if (not ptr->read_buffer_length)
+    if (ptr->read_buffer_length == 0)
     {
       ssize_t data_read;
       do
@@ -426,18 +403,22 @@ memcached_return_t memcached_io_read(memcached_server_write_instance_st ptr,
             continue;
 
           case ETIMEDOUT: // OSX
+#if EWOULDBLOCK != EAGAIN
           case EWOULDBLOCK:
-#ifdef USE_EAGAIN
-          case EAGAIN:
 #endif
+          case EAGAIN:
 #ifdef TARGET_OS_LINUX
           case ERESTART:
 #endif
-            if (memcached_success(io_wait(ptr, MEM_READ)))
             {
-              continue;
+              memcached_return_t io_wait_ret;
+              if (memcached_success(io_wait_ret= io_wait(ptr, MEM_READ)))
+              {
+                continue;
+              }
+
+              return io_wait_ret;
             }
-            return MEMCACHED_IN_PROGRESS;
 
             /* fall through */
 
@@ -534,10 +515,10 @@ memcached_return_t memcached_io_slurp(memcached_server_write_instance_st ptr)
         continue;
 
       case ETIMEDOUT: // OSX
+#if EWOULDBLOCK != EAGAIN
       case EWOULDBLOCK:
-#ifdef USE_EAGAIN
-      case EAGAIN:
 #endif
+      case EAGAIN:
 #ifdef TARGET_OS_LINUX
       case ERESTART:
 #endif
@@ -567,15 +548,17 @@ memcached_return_t memcached_io_slurp(memcached_server_write_instance_st ptr)
   return MEMCACHED_CONNECTION_FAILURE;
 }
 
-static ssize_t _io_write(memcached_server_write_instance_st ptr,
-                         const void *buffer, size_t length, bool with_flush)
+static bool _io_write(memcached_server_write_instance_st ptr,
+                      const void *buffer, size_t length, bool with_flush,
+                      size_t& written)
 {
   WATCHPOINT_ASSERT(ptr->fd != INVALID_SOCKET);
   assert(memcached_is_udp(ptr->root) == false);
 
-  size_t original_length= length;
   const char *buffer_ptr= static_cast<const char *>(buffer);
 
+  const size_t original_length= length;
+
   while (length)
   {
     char *write_ptr;
@@ -596,7 +579,8 @@ static ssize_t _io_write(memcached_server_write_instance_st ptr,
       memcached_return_t rc;
       if (io_flush(ptr, with_flush, rc) == false)
       {
-        return -1;
+        written= original_length -length;
+        return false;
       }
     }
   }
@@ -607,22 +591,33 @@ static ssize_t _io_write(memcached_server_write_instance_st ptr,
     WATCHPOINT_ASSERT(ptr->fd != INVALID_SOCKET);
     if (io_flush(ptr, with_flush, rc) == false)
     {
-      return -1;
+      written= original_length -length;
+      return false;
     }
   }
 
-  return (ssize_t) original_length;
+  written= original_length -length;
+
+  return true;
 }
 
 bool memcached_io_write(memcached_server_write_instance_st ptr)
 {
-  return (_io_write(ptr, NULL, 0, true) >= 0);
+  size_t written;
+  return _io_write(ptr, NULL, 0, true, written);
 }
 
 ssize_t memcached_io_write(memcached_server_write_instance_st ptr,
                            const void *buffer, const size_t length, const bool with_flush)
 {
-  return _io_write(ptr, buffer, length, with_flush);
+  size_t written;
+
+  if (_io_write(ptr, buffer, length, with_flush, written) == false)
+  {
+    return -1;
+  }
+
+  return ssize_t(written);
 }
 
 ssize_t memcached_io_writev(memcached_server_write_instance_st ptr,
@@ -633,15 +628,14 @@ ssize_t memcached_io_writev(memcached_server_write_instance_st ptr,
 
   for (size_t x= 0; x < number_of; x++, vector++)
   {
-    ssize_t returnable;
-
     if (vector->length)
     {
-      if ((returnable= _io_write(ptr, vector->buffer, vector->length, false)) == -1)
+      size_t written;
+      if ((_io_write(ptr, vector->buffer, vector->length, false, written)) == false)
       {
         return -1;
       }
-      total+= returnable;
+      total+= written;
     }
   }
 
@@ -684,9 +678,9 @@ memcached_server_write_instance_st memcached_io_get_readable_server(memcached_st
 {
 #define MAX_SERVERS_TO_POLL 100
   struct pollfd fds[MAX_SERVERS_TO_POLL];
-  unsigned int host_index= 0;
+  nfds_t host_index= 0;
 
-  for (uint32_t x= 0; x < memcached_server_count(memc) && host_index < MAX_SERVERS_TO_POLL; ++x)
+  for (uint32_t x= 0; x < memcached_server_count(memc) and host_index < MAX_SERVERS_TO_POLL; ++x)
   {
     memcached_server_write_instance_st instance= memcached_server_instance_fetch(memc, x);
 
@@ -731,17 +725,18 @@ memcached_server_write_instance_st memcached_io_get_readable_server(memcached_st
     break;
 
   default:
-    for (size_t x= 0; x < host_index; ++x)
+    for (nfds_t x= 0; x < host_index; ++x)
     {
       if (fds[x].revents & POLLIN)
       {
         for (uint32_t y= 0; y < memcached_server_count(memc); ++y)
         {
-          memcached_server_write_instance_st instance=
-            memcached_server_instance_fetch(memc, y);
+          memcached_server_write_instance_st instance= memcached_server_instance_fetch(memc, y);
 
           if (instance->fd == fds[x].fd)
+          {
             return instance;
+          }
         }
       }
     }
@@ -826,7 +821,7 @@ memcached_return_t memcached_io_readline(memcached_server_write_instance_st ptr,
     }
 
     /* Now let's look in the buffer and copy as we go! */
-    while (ptr->read_buffer_length && total_nr < size && !line_complete)
+    while (ptr->read_buffer_length and total_nr < size and line_complete == false)
     {
       *buffer_ptr = *ptr->read_ptr;
       if (*buffer_ptr == '\n')