This patch adds a new third-party library that implements an ELF dynamic linker.

third_party/crazy_linker/crazy_linker/src/crazy_linker_search_path_list.cpp

Index: third_party/crazy_linker/crazy_linker/src/crazy_linker_search_path_list.cpp
diff --git a/third_party/crazy_linker/crazy_linker/src/crazy_linker_search_path_list.cpp b/third_party/crazy_linker/crazy_linker/src/crazy_linker_search_path_list.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..a83fadd22c6ac5d4c20c572668c4f7a2200867b5
--- /dev/null
+++ b/third_party/crazy_linker/crazy_linker/src/crazy_linker_search_path_list.cpp
@@ -0,0 +1,82 @@
+// Copyright (c) 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 "crazy_linker_search_path_list.h"
+
+#include <string.h>
+
+#include "crazy_linker_debug.h"
+#include "crazy_linker_system.h"
+
+namespace crazy {
+
+void SearchPathList::Reset() {
+  list_.Resize(0);
+  full_path_.Resize(0);
+}
+
+void SearchPathList::ResetFromEnv(const char* var_name) {
+  Reset();
+  const char* env = GetEnv(var_name);
+  if (env && *env)
+    env_list_ = env;
+}
+
+void SearchPathList::AddPaths(const char* list, const char* list_end) {
+  // Append a column to the current list, if necessary
+  if (list_.size() > 0 && list_[list_.size() - 1] != ':')
+    list_ += ':';
+  list_.Append(list, list_end - list);
+}
+
+const char* SearchPathList::FindFile(const char* file_name) {
+  // Sanity checks.
+  if (!file_name || !*file_name)
+    return NULL;
+
+  LOG("%s: Looking for %s\n", __FUNCTION__, file_name);
+
+  // Build full list by appending the env_list_ after the regular one.
+  String full_list = list_;
+  if (env_list_.size() > 0) {
+    if (full_list.size() > 0 && full_list[full_list.size() -1 ] != ':')
+      full_list += ':';
+    full_list += env_list_;
+  }
+
+  // Iterate over all items in the list.
+  const char* p = full_list.c_str();
+  const char* end = p + full_list.size();
+
+  while (p < end) {
+    // compute current list item, and next item start at the same time.
+    const char* item = p;
+    const char* item_end =
+        reinterpret_cast<const char*>(memchr(p, ':', end - p));
+    if (item_end)
+      p = item_end + 1;
+    else {
+      item_end = end;
+      p = end;
+    }
+
+    full_path_.Assign(item, item_end - item);
+
+    // Add trailing directory separator if needed.
+    if (full_path_.size() > 0 && full_path_[full_path_.size() - 1] != '/')
+      full_path_ += '/';
+
+    full_path_ += file_name;
+
+    if (PathIsFile(full_path_.c_str())) {
+      LOG("    FOUND %s\n", full_path_.c_str());
+      return full_path_.c_str();
+    } else
+      LOG("    skip  %s\n", full_path_.c_str());
+  }
+
+  return NULL;
+}
+
+}  // namespace crazy