Move the android library loader from content to base

content/shell/android/linker_test_apk/content_linker_test_linker_tests.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.
-
-// This file implements the native methods of
-// org.content.chromium.app.LinkerTests
-// Unlike the content of linker_jni.cc, it is part of the content library and
-// can
-// thus use base/ and the C++ STL.
-
-#include "content/shell/android/linker_test_apk/content_linker_test_linker_tests.h"
-
-#include <errno.h>
-#include <sys/mman.h>
-#include <stdio.h>
-#include <string>
-
-#include "base/basictypes.h"
-#include "base/debug/proc_maps_linux.h"
-#include "base/logging.h"
-#include "base/strings/stringprintf.h"
-
-#include "jni/LinkerTests_jni.h"
-
-namespace content {
-
-namespace {
-
-using base::debug::MappedMemoryRegion;
-
-jboolean RunChecks(bool in_browser_process, bool need_relros) {
-
-  // IMPORTANT NOTE: The Python test control script reads the logcat for
-  // lines like:
-  //   BROWSER_LINKER_TEST: <status>
-  //   RENDERER_LINKER_TEST: <status>
-  //
-  // Where <status> can be either SUCCESS or FAIL. Other lines starting
-  // with the same prefixes, but not using SUCCESS or FAIL are ignored.
-  const char* prefix =
-      in_browser_process ? "BROWSER_LINKER_TEST: " : "RENDERER_LINKER_TEST: ";
-
-  // The RELRO section(s), after being copied into an ashmem region, will
-  // appear in /proc/self/maps as a mapped memory region for a file name
-  // that begins with the following prefix.
-  //
-  // Note that the full name will be something like:
-  //   "/dev/ashmem/RELRO:<libname> (deleted)"
-  //
-  // Where <libname> is the library name and '(deleted)' is actually
-  // added by the kernel to indicate there is no corresponding file
-  // on the filesystem.
-  //
-  // For regular builds, there is only one library, and thus one RELRO
-  // section, but for the component build, there are several libraries,
-  // each one with its own RELRO.
-  static const char kRelroSectionPrefix[] = "/dev/ashmem/RELRO:";
-
-  // Parse /proc/self/maps and builds a list of region mappings in this
-  // process.
-  std::string maps;
-  base::debug::ReadProcMaps(&maps);
-  if (maps.empty()) {
-    LOG(ERROR) << prefix << "FAIL Cannot parse /proc/self/maps";
-    return false;
-  }
-
-  std::vector<MappedMemoryRegion> regions;
-  base::debug::ParseProcMaps(maps, &regions);
-  if (regions.empty()) {
-    LOG(ERROR) << prefix << "FAIL Cannot read memory mappings in this process";
-    return false;
-  }
-
-  size_t num_shared_relros = 0;
-  size_t num_bad_shared_relros = 0;
-
-  for (size_t n = 0; n < regions.size(); ++n) {
-    MappedMemoryRegion& region = regions[n];
-
-    if (region.path.find(kRelroSectionPrefix) != 0) {
-      // Ignore any mapping that isn't a shared RELRO.
-      continue;
-    }
-
-    num_shared_relros++;
-
-    void* region_start = reinterpret_cast<void*>(region.start);
-    void* region_end = reinterpret_cast<void*>(region.end);
-
-    // Check that it is mapped read-only.
-    const uint8 expected_flags = MappedMemoryRegion::READ;
-    const uint8 expected_mask = MappedMemoryRegion::READ |
-                                MappedMemoryRegion::WRITE |
-                                MappedMemoryRegion::EXECUTE;
-
-    uint8 region_flags = region.permissions & expected_mask;
-    if (region_flags != expected_flags) {
-      LOG(ERROR)
-          << prefix
-          << base::StringPrintf(
-                 "Shared RELRO section at %p-%p is not mapped read-only. "
-                 "Protection flags are %d (%d expected)!",
-                 region_start,
-                 region_end,
-                 region_flags,
-                 expected_flags);
-      num_bad_shared_relros++;
-      continue;
-    }
-
-    // Check that trying to remap it read-write fails with EACCES
-    size_t region_size = region.end - region.start;
-    int ret = ::mprotect(region_start, region_size, PROT_READ | PROT_WRITE);
-    if (ret != -1) {
-      LOG(ERROR)
-          << prefix
-          << base::StringPrintf(
-                 "Shared RELRO section at %p-%p could be remapped read-write!?",
-                 region_start,
-                 region_end);
-      num_bad_shared_relros++;
-      // Just in case.
-      ::mprotect(region_start, region_size, PROT_READ);
-    } else if (errno != EACCES) {
-      LOG(ERROR) << prefix << base::StringPrintf(
-                                  "Shared RELRO section at %p-%p failed "
-                                  "read-write mprotect with "
-                                  "unexpected error %d (EACCES:%d wanted): %s",
-                                  region_start,
-                                  region_end,
-                                  errno,
-                                  EACCES,
-                                  strerror(errno));
-      num_bad_shared_relros++;
-    }
-  }
-
-  VLOG(0)
-      << prefix
-      << base::StringPrintf(
-             "There are %d shared RELRO sections in this process, %d are bad",
-             num_shared_relros,
-             num_bad_shared_relros);
-
-  if (num_bad_shared_relros > 0) {
-    LOG(ERROR) << prefix << "FAIL Bad Relros sections in this process";
-    return false;
-  }
-
-  if (need_relros) {
-    if (num_shared_relros == 0) {
-      LOG(ERROR) << prefix
-                 << "FAIL Missing shared RELRO sections in this process!";
-      return false;
-    }
-  } else {
-    if (num_shared_relros > 0) {
-      LOG(ERROR) << prefix << "FAIL Unexpected " << num_shared_relros
-                 << " shared RELRO sections in this process!";
-      return false;
-    }
-  }
-
-  VLOG(0) << prefix << "SUCCESS";
-  return true;
-}
-
-}  // namespace
-
-jboolean CheckForSharedRelros(JNIEnv* env,
-                              jclass clazz,
-                              jboolean in_browser_process) {
-  return RunChecks(in_browser_process, true);
-}
-
-jboolean CheckForNoSharedRelros(JNIEnv* env,
-                                jclass clazz,
-                                jboolean in_browser_process) {
-  return RunChecks(in_browser_process, false);
-}
-
-bool RegisterLinkerTestsJni(JNIEnv* env) { return RegisterNativesImpl(env); }
-
-}  // namespace content