Reorganize Multiprocess and implement for Windows

util/test/multiprocess_exec_test_child.cc

 // Copyright 2014 The Crashpad Authors. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
 // You may obtain a copy of the License at
 //
 //     http://www.apache.org/licenses/LICENSE-2.0
 //
 // Unless required by applicable law or agreed to in writing, software
 // distributed under the License is distributed on an "AS IS" BASIS,
@@ skipping 14 matching lines @@
 #elif defined(_WIN32)
 #define OS_WIN 1
 #endif
 
 #if defined(OS_POSIX)
 #include <unistd.h>
 #elif defined(OS_WIN)
 #include <windows.h>
 #endif
 
-#if defined(OS_WIN)
-
-namespace {
-
-// Various semi-documented NT internals to retrieve open handles.
-
-typedef enum _SYSTEM_INFORMATION_CLASS {
-  SystemHandleInformation = 16
-} SYSTEM_INFORMATION_CLASS;
-
-typedef struct _SYSTEM_HANDLE_INFORMATION {
-  USHORT ProcessId;
-  USHORT CreatorBackTraceIndex;
-  UCHAR ObjectTypeNumber;
-  UCHAR Flags;
-  USHORT Handle;
-  PVOID Object;
-  ACCESS_MASK GrantedAccess;
-} SYSTEM_HANDLE_INFORMATION, *PSYSTEM_HANDLE_INFORMATION;
-
-typedef struct _SYSTEM_HANDLE_INFORMATION_EX {
-  ULONG NumberOfHandles;
-  SYSTEM_HANDLE_INFORMATION Information[1];
-} SYSTEM_HANDLE_INFORMATION_EX, *PSYSTEM_HANDLE_INFORMATION_EX;
-
-typedef NTSTATUS(WINAPI* NTQUERYSYSTEMINFORMATION)(
-    SYSTEM_INFORMATION_CLASS SystemInformationClass,
-    PVOID SystemInformation,
-    ULONG SystemInformationLength,
-    PULONG ReturnLength);
-
-void EnsureOnlyStdioHandlesOpen() {
-  // Initialize the NTAPI functions we need.
-  HMODULE ntdll_handle = GetModuleHandle(L"ntdll.dll");
-  if (!ntdll_handle) {
-    fprintf(stderr, "GetModuleHandle ntdll.dll failed.\n");
-    abort();
-  }
-
-  NTQUERYSYSTEMINFORMATION NtQuerySystemInformation;
-  NtQuerySystemInformation = reinterpret_cast<NTQUERYSYSTEMINFORMATION>(
-                      GetProcAddress(ntdll_handle, "NtQuerySystemInformation"));
-  if (!NtQuerySystemInformation) {
-    fprintf(stderr, "GetProcAddress NtQuerySystemInformation failed.\n");
-    abort();
-  }
-
-  // Get the number of handles on the system.
-  DWORD buffer_size = 0;
-  SYSTEM_HANDLE_INFORMATION_EX temp_info;
-  NTSTATUS status = NtQuerySystemInformation(
-      SystemHandleInformation, &temp_info, sizeof(temp_info), &buffer_size);
-  if (!buffer_size) {
-    fprintf(stderr,
-            "NtQuerySystemInformation for number of handles failed: 0x%lX\n",
-            status);
-    abort();
-  }
-
-  SYSTEM_HANDLE_INFORMATION_EX *system_handles =
-      reinterpret_cast<SYSTEM_HANDLE_INFORMATION_EX*>(new BYTE[buffer_size]);
-
-  // This is likely flaky as we're racing with other handles being created on
-  // the system between the size query above, and the actual retrieval here.
-  status = NtQuerySystemInformation(SystemHandleInformation, system_handles,
-                                    buffer_size, &buffer_size);
-  if (status != 0) {
-    fprintf(stderr, "Failed to get the handle list: 0x%lX\n", status);
-    delete[] system_handles;
-    abort();
-  }
-
-  for (ULONG i = 0; i < system_handles->NumberOfHandles; ++i) {
-    USHORT h = system_handles->Information[i].Handle;
-    if (system_handles->Information[i].ProcessId != GetCurrentProcessId())
-      continue;
-
-    // TODO(scottmg): This is probably insufficient, we'll need to allow having
-    // a few other standard handles open (for example, to the window station),
-    // or only check for handles of certain types.
-    HANDLE handle = reinterpret_cast<HANDLE>(h);
-    if (handle != GetStdHandle(STD_INPUT_HANDLE) &&
-        handle != GetStdHandle(STD_OUTPUT_HANDLE) &&
-        handle != GetStdHandle(STD_ERROR_HANDLE)) {
-      fprintf(stderr, "Handle 0x%lX is not stdio handle\n", handle);
-      abort();
-    }
-  }
-
-  delete [] system_handles;
-}
-
-}  // namespace
-
-#endif  // OS_WIN
-
 int main(int argc, char* argv[]) {
 #if defined(OS_POSIX)
   // Make sure that there’s nothing open at any FD higher than 3. All FDs other
   // than stdin, stdout, and stderr should have been closed prior to or at
   // exec().
   int max_fd = std::max(static_cast<int>(sysconf(_SC_OPEN_MAX)), OPEN_MAX);
   max_fd = std::max(max_fd, getdtablesize());
   for (int fd = STDERR_FILENO + 1; fd < max_fd; ++fd) {
     if (close(fd) == 0 || errno != EBADF) {
       abort();
     }
   }
 
   // Read a byte from stdin, expecting it to be a specific value.
   char c;
   ssize_t rv = read(STDIN_FILENO, &c, 1);
   if (rv != 1 || c != 'z') {
     abort();
   }
 
   // Write a byte to stdout.
   c = 'Z';
   rv = write(STDOUT_FILENO, &c, 1);
   if (rv != 1) {
     abort();
   }
 #elif defined(OS_WIN)
-  // Make sure there's nothing open other than stdin, stdout, and stderr.
-  EnsureOnlyStdioHandlesOpen();
+  // TODO(scottmg): Verify that only the handles we expect to be open, are.
 
   // Read a byte from stdin, expecting it to be a specific value.
   char c;
   DWORD bytes_read;
-  if (!ReadFile(GetStdHandle(STD_INPUT_HANDLE), &c, 1, &bytes_read, nullptr) ||
+  HANDLE stdin_handle = GetStdHandle(STD_INPUT_HANDLE);
+  if (!ReadFile(stdin_handle, &c, 1, &bytes_read, nullptr) ||
       bytes_read != 1 || c != 'z') {
     abort();
   }
 
   // Write a byte to stdout.
   c = 'Z';
   DWORD bytes_written;
   if (!WriteFile(
           GetStdHandle(STD_OUTPUT_HANDLE), &c, 1, &bytes_written, nullptr) ||
       bytes_written != 1) {
     abort();
   }
 #endif  // OS_POSIX
 
   return 0;
 }