Bug 1194935 - Add a C++ implementation of kill_and_get_minidump as part of the build to accommodate dumping 64 bit Firefox from 32 bit python. r=ted

testing/mochitest/Makefile.in

@@ -33,6 +33,7 @@ ifeq ($(OS_ARCH),WINNT)
 TEST_HARNESS_BINS += \
   crashinject$(BIN_SUFFIX) \
   crashinjectdll$(DLL_SUFFIX) \
+  minidumpwriter$(BIN_SUFFIX) \
   $(NULL)
 endif
 

testing/mochitest/runtests.py

@@ -1783,7 +1783,8 @@ class MochitestDesktop(MochitestBase):
             try:
                 minidump_path = os.path.join(self.profile.profile,
                                              'minidumps')
-                mozcrash.kill_and_get_minidump(processPID, minidump_path)
+                mozcrash.kill_and_get_minidump(processPID, minidump_path,
+                                               utilityPath)
             except OSError:
                 # https://bugzilla.mozilla.org/show_bug.cgi?id=921509
                 self.log.info(

testing/mozbase/mozcrash/mozcrash/mozcrash.py

@@ -364,7 +364,7 @@ if mozinfo.isWin:
     OpenProcess = kernel32.OpenProcess
     CloseHandle = kernel32.CloseHandle
 
-    def write_minidump(pid, dump_directory):
+    def write_minidump(pid, dump_directory, utility_path):
         """
         Write a minidump for a process.
 
@@ -379,13 +379,38 @@ if mozinfo.isWin:
         FILE_ATTRIBUTE_NORMAL = 0x80
         INVALID_HANDLE_VALUE = -1
 
+        file_name = os.path.join(dump_directory,
+                                 str(uuid.uuid4()) + ".dmp")
+
+        if (mozinfo.info['bits'] != ctypes.sizeof(ctypes.c_voidp) * 8 and
+            utility_path):
+            # We're not going to be able to write a minidump with ctypes if our
+            # python process was compiled for a different architecture than
+            # firefox, so we invoke the minidumpwriter utility program.
+
+            log = get_logger()
+            minidumpwriter = os.path.normpath(os.path.join(utility_path,
+                                                           "minidumpwriter.exe"))
+            log.info("Using %s to write a dump to %s for [%d]" %
+                     (minidumpwriter, file_name, pid))
+            if not os.path.exists(minidumpwriter):
+                log.error("minidumpwriter not found in %s" % utility_path)
+                return
+
+            if isinstance(file_name, unicode):
+                # Convert to a byte string before sending to the shell.
+                file_name = file_name.encode(sys.getfilesystemencoding())
+
+            status = subprocess.Popen([minidumpwriter, str(pid), file_name]).wait()
+            if status:
+                log.error("minidumpwriter exited with status: %d" % status)
+            return
+
         proc_handle = OpenProcess(PROCESS_QUERY_INFORMATION | PROCESS_VM_READ,
                                   0, pid)
         if not proc_handle:
             return
 
-        file_name = os.path.join(dump_directory,
-                                 str(uuid.uuid4()) + ".dmp")
         if not isinstance(file_name, unicode):
             # Convert to unicode explicitly so our path will be valid as input
             # to CreateFileW
@@ -433,7 +458,7 @@ else:
         """
         os.kill(pid, signal.SIGKILL)
 
-def kill_and_get_minidump(pid, dump_directory=None):
+def kill_and_get_minidump(pid, dump_directory, utility_path=None):
     """
     Attempt to kill a process and leave behind a minidump describing its
     execution state.
@@ -453,7 +478,7 @@ def kill_and_get_minidump(pid, dump_directory=None):
     """
     needs_killing = True
     if mozinfo.isWin:
-        write_minidump(pid, dump_directory)
+        write_minidump(pid, dump_directory, utility_path)
     elif mozinfo.isLinux or mozinfo.isMac:
         os.kill(pid, signal.SIGABRT)
         needs_killing = False

testing/tools/minidumpwriter/minidumpwriter.cpp

@@ -0,0 +1,59 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+
+/*
+ * Given a PID and a path to a target file, write a minidump of the
+ * corresponding process in that file. This is taken more or less
+ * verbatim from mozcrash and translated to C++ to avoid problems
+ * writing a minidump of 64 bit Firefox from a 32 bit python.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <windows.h>
+#include <dbghelp.h>
+
+int wmain(int argc, wchar_t** argv)
+{
+  if (argc != 3) {
+    fprintf(stderr, "Usage: minidumpwriter <PID> <DUMP_FILE>\n");
+    return 1;
+  }
+
+  DWORD pid = (DWORD) _wtoi(argv[1]);
+
+  if (pid <= 0) {
+    fprintf(stderr, "Usage: minidumpwriter <PID> <DUMP_FILE>\n");
+    return 1;
+  }
+
+  wchar_t* dumpfile = argv[2];
+  int rv = 1;
+  HANDLE hProcess = OpenProcess(PROCESS_QUERY_INFORMATION | PROCESS_VM_READ,
+                                0, pid);
+  if (!hProcess) {
+    fprintf(stderr, "Couldn't get handle for %d\n", pid);
+    return rv;
+  }
+
+  HANDLE file = CreateFileW(dumpfile, GENERIC_WRITE, 0, nullptr, CREATE_ALWAYS,
+                            FILE_ATTRIBUTE_NORMAL, nullptr);
+  if (file == INVALID_HANDLE_VALUE) {
+    fprintf(stderr, "Couldn't open dump file at %S\n", dumpfile);
+    CloseHandle(hProcess);
+    return rv;
+  }
+
+  rv = 0;
+  if (!MiniDumpWriteDump(hProcess, pid, file, MiniDumpNormal,
+                         nullptr, nullptr, nullptr)) {
+    fprintf(stderr, "Error 0x%X in MiniDumpWriteDump\n", GetLastError());
+    rv = 1;
+  }
+
+  CloseHandle(file);
+  CloseHandle(hProcess);
+  return rv;
+}

testing/tools/minidumpwriter/moz.build

@@ -0,0 +1,17 @@
+# -*- Mode: python; c-basic-offset: 4; indent-tabs-mode: nil; tab-width: 40 -*-
+# vim: set filetype=python:
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+if CONFIG['ENABLE_TESTS'] and CONFIG['CPU_ARCH'] == 'x86_64' and CONFIG['OS_ARCH'] == 'WINNT':
+    Program('minidumpwriter')
+    OS_LIBS += [
+        'dbghelp',
+    ]
+    SOURCES += [
+        'minidumpwriter.cpp',
+    ]
+    USE_STATIC_LIBS = True
+
+NO_PGO = True

toolkit/toolkit.mozbuild

@@ -172,6 +172,7 @@ if CONFIG['ENABLE_TESTS']:
     DIRS += [
         '/testing/mochitest',
         '/testing/xpcshell',
+        '/testing/tools/minidumpwriter',
         '/testing/tools/screenshot',
         '/testing/profiles',
         '/testing/mozbase',