1    :  // Copyright 2015 Google Inc. All Rights Reserved.
   2    :  //
   3    :  // Licensed under the Apache License, Version 2.0 (the "License");
   4    :  // you may not use this file except in compliance with the License.
   5    :  // You may obtain a copy of the License at
   6    :  //
   7    :  //     http://www.apache.org/licenses/LICENSE-2.0
   8    :  //
   9    :  // Unless required by applicable law or agreed to in writing, software
  10    :  // distributed under the License is distributed on an "AS IS" BASIS,
  11    :  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12    :  // See the License for the specific language governing permissions and
  13    :  // limitations under the License.
  14    :  
  15    :  #include "syzygy/common/process_utils.h"
  16    :  
  17    :  #include <psapi.h>
  18    :  
  19    :  #include "base/logging.h"
  20    :  #include "base/win/pe_image.h"
  21    :  #include "syzygy/common/com_utils.h"
  22    :  #include "syzygy/common/path_util.h"
  23    :  
  24    :  namespace common {
  25    :  
  26  E :  bool GetCurrentProcessModules(ModuleVector* modules) {
  27  E :    return GetProcessModules(::GetCurrentProcess(), modules);
  28  E :  }
  29    :  
  30  E :  bool GetProcessModules(HANDLE process, ModuleVector* modules) {
  31  E :    DCHECK(modules != NULL);
  32    :  
  33  E :    modules->resize(128);
  34  E :    while (true) {
  35  E :      DWORD bytes_required = 0;
  36    :      // EnumProcessModules expects a DWORD as size, so it should fit.
  37  E :      DCHECK_LE(modules->size() * sizeof(modules->at(0)),
  38  E :                std::numeric_limits<DWORD>::max());
  39    :      // EnumProcessModules returns 'success' even if the buffer size is too
  40    :      // small.
  41  E :      if (!::EnumProcessModules(
  42    :              process,
  43    :              modules->data(),
  44    :              static_cast<DWORD>(modules->size() * sizeof(modules->at(0))),
  45    :              &bytes_required)) {
  46  i :        DPLOG(ERROR) << "::EnumProcessModules";
  47  i :        modules->clear();
  48  i :        return false;
  49    :      }
  50  E :      DCHECK_EQ(0u, bytes_required % sizeof(modules->at(0)));
  51  E :      size_t num_modules = bytes_required / sizeof(modules->at(0));
  52  E :      if (num_modules <= modules->size()) {
  53    :        // Buffer size was too big, presumably because a module was unloaded.
  54  E :        modules->resize(num_modules);
  55  E :        return true;
  56  i :      } else if (num_modules == 0) {
  57  i :        DLOG(ERROR) << "Can't determine the module list size.";
  58  i :        modules->clear();
  59  i :        return false;
  60  i :      } else {
  61    :        // Buffer size was too small. Try again with a larger buffer.
  62  i :        modules->resize(num_modules + 4, NULL);
  63    :      }
  64  i :    }
  65  E :  }
  66    :  
  67    :  }  // namespace common