[NaCl SDK] Add some more logging to nacl_io.

native_client_sdk/src/libraries/nacl_io/dir_node.cc

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "nacl_io/dir_node.h"
 
 #include <errno.h>
 #include <string.h>
 
+#include "nacl_io/log.h"
 #include "nacl_io/osdirent.h"
 #include "nacl_io/osstat.h"
 #include "sdk_util/auto_lock.h"
 #include "sdk_util/macros.h"
 
 namespace nacl_io {
 
 namespace {
 
 // TODO(binji): For now, just use a dummy value for the parent ino.
@@ skipping 13 matching lines @@
   for (NodeMap_t::iterator it = map_.begin(); it != map_.end(); ++it) {
     it->second->Unlink();
   }
 }
 
 Error DirNode::Read(const HandleAttr& attr,
                     void* buf,
                     size_t count,
                     int* out_bytes) {
   *out_bytes = 0;
+  LOG_TRACE("Can't read a directory.");
   return EISDIR;
 }
 
 Error DirNode::FTruncate(off_t size) {
+  LOG_TRACE("Can't truncate a directory.");
   return EISDIR;
 }
 
 Error DirNode::Write(const HandleAttr& attr,
                      const void* buf,
                      size_t count,
                      int* out_bytes) {
   *out_bytes = 0;
+  LOG_TRACE("Can't write to a directory.");
   return EISDIR;
 }
 
 Error DirNode::GetDents(size_t offs,
                         dirent* pdir,
                         size_t size,
                         int* out_bytes) {
   AUTO_LOCK(node_lock_);
   BuildCache_Locked();
   return cache_.GetDents(offs, pdir, size, out_bytes);
 }
 
 Error DirNode::AddChild(const std::string& name, const ScopedNode& node) {
   AUTO_LOCK(node_lock_);
 
-  if (name.empty())
+  if (name.empty()) {
+    LOG_ERROR("Can't add child with no name.");
     return ENOENT;
+  }
 
-  if (name.length() >= MEMBER_SIZE(dirent, d_name))
+  if (name.length() >= MEMBER_SIZE(dirent, d_name)) {
+    LOG_ERROR("Child name is too long: %d >= %d",
+              name.length(),
+              MEMBER_SIZE(dirent, d_name));
     return ENAMETOOLONG;
+  }
 
   NodeMap_t::iterator it = map_.find(name);
-  if (it != map_.end())
+  if (it != map_.end()) {
+    LOG_TRACE("Can't add child \"%s\", it already exists.", name);
     return EEXIST;
+  }
 
   node->Link();
   map_[name] = node;
   ClearCache_Locked();
   return 0;
 }
 
 Error DirNode::RemoveChild(const std::string& name) {
   AUTO_LOCK(node_lock_);
   NodeMap_t::iterator it = map_.find(name);
@@ skipping 36 matching lines @@
 
   cache_built_ = true;
 }
 
 void DirNode::ClearCache_Locked() {
   cache_built_ = false;
   cache_.Reset();
 }
 
 }  // namespace nacl_io