Ninja: add wrapper for cl to extract dependencies

cmcldeps wraps cl and adds /showInclude before calling cl.
It parses the output of cl for used headers, drops system
headers and writes them to a GCC like dependency file.

cmcldeps uses ATM ninja code for process handling,
but could be ported later to SystemTools.

TODO: Why needs ninja multiple calls in the BuildDepends test?

6 files changed, 697 insertions, 9 deletions

diff --git a/Modules/Platform/Windows-cl.cmake b/Modules/Platform/Windows-cl.cmake
index be6abb690d..eed4e52da3 100644
--- a/Modules/Platform/Windows-cl.cmake
+++ b/Modules/Platform/Windows-cl.cmake
@@ -251,3 +251,21 @@ IF(NOT EXISTS "${CMAKE_PLATFORM_ROOT_BIN}/CMakeCXXPlatform.cmake")
   CONFIGURE_FILE(${CMAKE_ROOT}/Modules/Platform/Windows-cl.cmake.in 
                ${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeCXXPlatform.cmake IMMEDIATE)
 ENDIF(NOT EXISTS "${CMAKE_PLATFORM_ROOT_BIN}/CMakeCXXPlatform.cmake")
+
+
+IF(CMAKE_GENERATOR MATCHES "Ninja" AND CMAKE_C_COMPILER)
+  # TODO try_compile doesn't need cmcldeps, find a better solution
+  if(NOT EXISTS ${CMAKE_TRY_COMPILE_SOURCE_DIR}/../ShowIncludes)
+    SET(showdir ${CMAKE_BINARY_DIR}/CMakeFiles/ShowIncludes)
+    FILE(WRITE ${showdir}/foo.h "\n")
+    FILE(WRITE ${showdir}/main.c "#include \"foo.h\" \nint main(){}\n")
+    EXECUTE_PROCESS(COMMAND ${CMAKE_C_COMPILER} /nologo /showIncludes ${showdir}/main.c
+                    WORKING_DIRECTORY ${showdir} OUTPUT_VARIABLE showOut)
+    STRING(REPLACE main.c "" showOut1 ${showOut})
+    STRING(REPLACE "/" "\\" header1 ${showdir}/foo.h)
+    STRING(TOLOWER ${header1} header2)
+    STRING(REPLACE ${header2} "" showOut2 ${showOut1})
+    STRING(REPLACE "\n" "" showOut3 ${showOut2})
+    SET(CMAKE_CL_SHOWINCLUDE_PREFIX ${showOut3})
+  ENDIF()
+ENDIF()
diff --git a/Source/CMakeLists.txt b/Source/CMakeLists.txt
index 46bdec6b9a..ebeda5679d 100644
--- a/Source/CMakeLists.txt
+++ b/Source/CMakeLists.txt
@@ -383,6 +383,10 @@ IF(CMAKE_ENABLE_NINJA)
     cmNinjaUtilityTargetGenerator.h
     )
   ADD_DEFINITIONS(-DCMAKE_USE_NINJA)
+  IF(MSVC) # TODO WIN32
+    ADD_EXECUTABLE(cmcldeps cmcldeps.cxx)
+    INSTALL_TARGETS(/bin cmcldeps)
+  ENDIF()
 ELSE()
   MESSAGE(STATUS "Ninja generator disabled, enforce with -DCMAKE_ENABLE_NINJA=ON")
 ENDIF()
diff --git a/Source/cmGlobalNinjaGenerator.cxx b/Source/cmGlobalNinjaGenerator.cxx
index c4b1cc999d..9a2597b299 100644
--- a/Source/cmGlobalNinjaGenerator.cxx
+++ b/Source/cmGlobalNinjaGenerator.cxx
@@ -460,17 +460,28 @@ void cmGlobalNinjaGenerator
       // check if mingw is used
       const char* cc = mf->GetDefinition("CMAKE_C_COMPILER");
       if(cc && std::string(cc).find("gcc.exe") != std::string::npos)
-      {
+        {
         UsingMinGW = true;
         std::string rc = cmSystemTools::FindProgram("windres");
         if(rc.empty())
           rc = "windres.exe";;
         mf->AddDefinition("CMAKE_RC_COMPILER", rc.c_str());
         }
+      else if (cc && std::string(cc).find("cl.exe") != std::string::npos)
+        {
+        const char* cmake = mf->GetDefinition("CMAKE_COMMAND");
+        std::string bindir = cmake ? cmake : "";
+        cmSystemTools::ReplaceString(bindir, "cmake.exe", "");
+        std::vector<std::string> locations;
+        locations.push_back(bindir);
+        std::string cldeps = cmSystemTools::FindProgram("cmcldeps", locations);
+        if(!cldeps.empty())
+          mf->AddDefinition("CMAKE_CMCLDEPS_EXECUTABLE", cldeps.c_str());
+        }
       }
     this->cmGlobalGenerator::EnableLanguage(language, mf, optional);
     this->ResolveLanguageCompiler(*l, mf, optional);
-  }
+    }
 }
 
 bool cmGlobalNinjaGenerator::UsingMinGW = false;
diff --git a/Source/cmNinjaTargetGenerator.cxx b/Source/cmNinjaTargetGenerator.cxx
index 74b5c9213b..6518727aef 100644
--- a/Source/cmNinjaTargetGenerator.cxx
+++ b/Source/cmNinjaTargetGenerator.cxx
@@ -330,16 +330,20 @@ cmNinjaTargetGenerator
   vars.Defines = "$DEFINES";
   vars.TargetPDB = "$TARGET_PDB";
 
-  bool cldeps = false;
+  const char* cldeps = 0;
+  const char* showIncludePrefix = 0;
   const char* cc = this->GetMakefile()->GetDefinition("CMAKE_C_COMPILER");
   if(cc && std::string(cc).find("cl.exe") != std::string::npos)
-    cldeps = true;
+    {
+    cldeps = this->GetMakefile()->GetDefinition("CMAKE_CMCLDEPS_EXECUTABLE");
+    showIncludePrefix = this->GetMakefile()->GetDefinition("CMAKE_CL_SHOWINCLUDE_PREFIX");
+    }
 
   std::string depfile;
   std::string depfileFlagsName = "CMAKE_DEPFILE_FLAGS_" + language;
   const char *depfileFlags =
     this->GetMakefile()->GetDefinition(depfileFlagsName.c_str());
-  if (depfileFlags || cldeps) {
+  if (depfileFlags || (cldeps && showIncludePrefix)) {
     std::string depfileFlagsStr = depfileFlags ? depfileFlags : "";
     depfile = "$out.d";
     cmSystemTools::ReplaceString(depfileFlagsStr, "<DEPFILE>",
@@ -369,8 +373,11 @@ cmNinjaTargetGenerator
   std::string cmdLine =
     this->GetLocalGenerator()->BuildCommandLine(compileCmds);
 
-  if(cldeps)
-      cmdLine = "cldeps.exe $out.d $out " + cmdLine;
+  if(cldeps && showIncludePrefix)
+    {
+    std::string prefix = showIncludePrefix;
+    cmdLine =  std::string(cldeps) + " $in $out.d $out " + "\"" + prefix + "\" " + cmdLine;
+    }
 
   // Write the rule for compiling file of the given language.
   std::ostringstream comment;
diff --git a/Source/cmcldeps.cxx b/Source/cmcldeps.cxx
new file mode 100644
index 0000000000..48f2cfd54e
--- /dev/null
+++ b/Source/cmcldeps.cxx
@@ -0,0 +1,644 @@
+/*
+    ninja's subprocess.h
+*/
+
+// Copyright 2012 Google Inc. 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,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef NINJA_SUBPROCESS_H_
+#define NINJA_SUBPROCESS_H_
+
+#include <string>
+#include <vector>
+#include <queue>
+using namespace std;
+
+#ifdef _WIN32
+#include <windows.h>
+#else
+#include <signal.h>
+#endif
+
+//#include "exit_status.h"
+enum ExitStatus {
+  ExitSuccess,
+  ExitFailure,
+  ExitInterrupted
+};
+
+/// Subprocess wraps a single async subprocess.  It is entirely
+/// passive: it expects the caller to notify it when its fds are ready
+/// for reading, as well as call Finish() to reap the child once done()
+/// is true.
+struct Subprocess {
+  ~Subprocess();
+
+  /// Returns ExitSuccess on successful process exit, ExitInterrupted if
+  /// the process was interrupted, ExitFailure if it otherwise failed.
+  ExitStatus Finish();
+
+  bool Done() const;
+
+  const string& GetOutput() const;
+
+ private:
+  Subprocess();
+  bool Start(struct SubprocessSet* set, const string& command);
+  void OnPipeReady();
+
+  string buf_;
+
+#ifdef _WIN32
+  /// Set up pipe_ as the parent-side pipe of the subprocess; return the
+  /// other end of the pipe, usable in the child process.
+  HANDLE SetupPipe(HANDLE ioport);
+
+  HANDLE child_;
+  HANDLE pipe_;
+  OVERLAPPED overlapped_;
+  char overlapped_buf_[4 << 10];
+  bool is_reading_;
+#else
+  int fd_;
+  pid_t pid_;
+#endif
+
+  friend struct SubprocessSet;
+};
+
+/// SubprocessSet runs a ppoll/pselect() loop around a set of Subprocesses.
+/// DoWork() waits for any state change in subprocesses; finished_
+/// is a queue of subprocesses as they finish.
+struct SubprocessSet {
+  SubprocessSet();
+  ~SubprocessSet();
+
+  Subprocess* Add(const string& command);
+  bool DoWork();
+  Subprocess* NextFinished();
+  void Clear();
+
+  vector<Subprocess*> running_;
+  queue<Subprocess*> finished_;
+
+#ifdef _WIN32
+  static BOOL WINAPI NotifyInterrupted(DWORD dwCtrlType);
+  static HANDLE ioport_;
+#else
+  static void SetInterruptedFlag(int signum);
+  static bool interrupted_;
+
+  struct sigaction old_act_;
+  sigset_t old_mask_;
+#endif
+};
+
+#endif // NINJA_SUBPROCESS_H_
+
+
+/*
+    ninja's util functions
+*/
+
+
+static void Fatal(const char* msg, ...) {
+  va_list ap;
+  fprintf(stderr, "ninja: FATAL: ");
+  va_start(ap, msg);
+  vfprintf(stderr, msg, ap);
+  va_end(ap);
+  fprintf(stderr, "\n");
+#ifdef _WIN32
+  // On Windows, some tools may inject extra threads.
+  // exit() may block on locks held by those threads, so forcibly exit.
+  fflush(stderr);
+  fflush(stdout);
+  ExitProcess(1);
+#else
+  exit(1);
+#endif
+}
+
+
+#ifdef _WIN32
+string GetLastErrorString() {
+  DWORD err = GetLastError();
+
+  char* msg_buf;
+  FormatMessageA(
+        FORMAT_MESSAGE_ALLOCATE_BUFFER |
+        FORMAT_MESSAGE_FROM_SYSTEM |
+        FORMAT_MESSAGE_IGNORE_INSERTS,
+        NULL,
+        err,
+        MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
+        (char*)&msg_buf,
+        0,
+        NULL);
+  string msg = msg_buf;
+  LocalFree(msg_buf);
+  return msg;
+}
+#endif
+
+#define snprintf _snprintf
+
+
+/*
+    ninja's subprocess-win32.cc
+*/
+
+// Copyright 2012 Google Inc. 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,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+//#include "subprocess.h"
+
+#include <stdio.h>
+
+#include <algorithm>
+
+//#include "util.h"
+
+namespace {
+
+void Win32Fatal(const char* function) {
+  Fatal("%s: %s", function, GetLastErrorString().c_str());
+}
+
+}  // anonymous namespace
+
+Subprocess::Subprocess() : child_(NULL) , overlapped_(), is_reading_(false) {
+}
+
+Subprocess::~Subprocess() {
+  if (pipe_) {
+    if (!CloseHandle(pipe_))
+      Win32Fatal("CloseHandle");
+  }
+  // Reap child if forgotten.
+  if (child_)
+    Finish();
+}
+
+HANDLE Subprocess::SetupPipe(HANDLE ioport) {
+  char pipe_name[100];
+  snprintf(pipe_name, sizeof(pipe_name),
+           "\\\\.\\pipe\\ninja_pid%u_sp%p", GetCurrentProcessId(), this);
+
+  pipe_ = ::CreateNamedPipeA(pipe_name,
+                             PIPE_ACCESS_INBOUND | FILE_FLAG_OVERLAPPED,
+                             PIPE_TYPE_BYTE,
+                             PIPE_UNLIMITED_INSTANCES,
+                             0, 0, INFINITE, NULL);
+  if (pipe_ == INVALID_HANDLE_VALUE)
+    Win32Fatal("CreateNamedPipe");
+
+  if (!CreateIoCompletionPort(pipe_, ioport, (ULONG_PTR)this, 0))
+    Win32Fatal("CreateIoCompletionPort");
+
+  memset(&overlapped_, 0, sizeof(overlapped_));
+  if (!ConnectNamedPipe(pipe_, &overlapped_) &&
+      GetLastError() != ERROR_IO_PENDING) {
+    Win32Fatal("ConnectNamedPipe");
+  }
+
+  // Get the write end of the pipe as a handle inheritable across processes.
+  HANDLE output_write_handle = CreateFile(pipe_name, GENERIC_WRITE, 0,
+                                          NULL, OPEN_EXISTING, 0, NULL);
+  HANDLE output_write_child;
+  if (!DuplicateHandle(GetCurrentProcess(), output_write_handle,
+                       GetCurrentProcess(), &output_write_child,
+                       0, TRUE, DUPLICATE_SAME_ACCESS)) {
+    Win32Fatal("DuplicateHandle");
+  }
+  CloseHandle(output_write_handle);
+
+  return output_write_child;
+}
+
+bool Subprocess::Start(SubprocessSet* set, const string& command) {
+  HANDLE child_pipe = SetupPipe(set->ioport_);
+
+  SECURITY_ATTRIBUTES security_attributes;
+  memset(&security_attributes, 0, sizeof(SECURITY_ATTRIBUTES));
+  security_attributes.nLength = sizeof(SECURITY_ATTRIBUTES);
+  security_attributes.bInheritHandle = TRUE;
+  // Must be inheritable so subprocesses can dup to children.
+  HANDLE nul = CreateFile("NUL", GENERIC_READ,
+          FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE,
+          &security_attributes, OPEN_EXISTING, 0, NULL);
+  if (nul == INVALID_HANDLE_VALUE)
+    Fatal("couldn't open nul");
+
+  STARTUPINFOA startup_info;
+  memset(&startup_info, 0, sizeof(startup_info));
+  startup_info.cb = sizeof(STARTUPINFO);
+  startup_info.dwFlags = STARTF_USESTDHANDLES;
+  startup_info.hStdInput = nul;
+  startup_info.hStdOutput = child_pipe;
+  startup_info.hStdError = child_pipe;
+
+  PROCESS_INFORMATION process_info;
+  memset(&process_info, 0, sizeof(process_info));
+
+  // Do not prepend 'cmd /c' on Windows, this breaks command
+  // lines greater than 8,191 chars.
+  if (!CreateProcessA(NULL, (char*)command.c_str(), NULL, NULL,
+                      /* inherit handles */ TRUE, CREATE_NEW_PROCESS_GROUP,
+                      NULL, NULL,
+                      &startup_info, &process_info)) {
+    DWORD error = GetLastError();
+    if (error == ERROR_FILE_NOT_FOUND) { // file (program) not found error is treated as a normal build action failure
+      if (child_pipe)
+        CloseHandle(child_pipe);
+      CloseHandle(pipe_);
+      CloseHandle(nul);
+      pipe_ = NULL;
+      // child_ is already NULL;
+      buf_ = "CreateProcess failed: The system cannot find the file specified.\n";
+      return true;
+    } else {
+      Win32Fatal("CreateProcess");    // pass all other errors to Win32Fatal
+    }
+  }
+
+  // Close pipe channel only used by the child.
+  if (child_pipe)
+    CloseHandle(child_pipe);
+  CloseHandle(nul);
+
+  CloseHandle(process_info.hThread);
+  child_ = process_info.hProcess;
+
+  return true;
+}
+
+void Subprocess::OnPipeReady() {
+  DWORD bytes;
+  if (!GetOverlappedResult(pipe_, &overlapped_, &bytes, TRUE)) {
+    if (GetLastError() == ERROR_BROKEN_PIPE) {
+      CloseHandle(pipe_);
+      pipe_ = NULL;
+      return;
+    }
+    Win32Fatal("GetOverlappedResult");
+  }
+
+  if (is_reading_ && bytes)
+    buf_.append(overlapped_buf_, bytes);
+
+  memset(&overlapped_, 0, sizeof(overlapped_));
+  is_reading_ = true;
+  if (!::ReadFile(pipe_, overlapped_buf_, sizeof(overlapped_buf_),
+                  &bytes, &overlapped_)) {
+    if (GetLastError() == ERROR_BROKEN_PIPE) {
+      CloseHandle(pipe_);
+      pipe_ = NULL;
+      return;
+    }
+    if (GetLastError() != ERROR_IO_PENDING)
+      Win32Fatal("ReadFile");
+  }
+
+  // Even if we read any bytes in the readfile call, we'll enter this
+  // function again later and get them at that point.
+}
+
+ExitStatus Subprocess::Finish() {
+  if (!child_)
+    return ExitFailure;
+
+  // TODO: add error handling for all of these.
+  WaitForSingleObject(child_, INFINITE);
+
+  DWORD exit_code = 0;
+  GetExitCodeProcess(child_, &exit_code);
+
+  CloseHandle(child_);
+  child_ = NULL;
+
+  return exit_code == 0              ? ExitSuccess :
+         exit_code == CONTROL_C_EXIT ? ExitInterrupted :
+                                       ExitFailure;
+}
+
+bool Subprocess::Done() const {
+  return pipe_ == NULL;
+}
+
+const string& Subprocess::GetOutput() const {
+  return buf_;
+}
+
+HANDLE SubprocessSet::ioport_;
+
+SubprocessSet::SubprocessSet() {
+  ioport_ = ::CreateIoCompletionPort(INVALID_HANDLE_VALUE, NULL, 0, 1);
+  if (!ioport_)
+    Win32Fatal("CreateIoCompletionPort");
+  if (!SetConsoleCtrlHandler(NotifyInterrupted, TRUE))
+    Win32Fatal("SetConsoleCtrlHandler");
+}
+
+SubprocessSet::~SubprocessSet() {
+  Clear();
+
+  SetConsoleCtrlHandler(NotifyInterrupted, FALSE);
+  CloseHandle(ioport_);
+}
+
+BOOL WINAPI SubprocessSet::NotifyInterrupted(DWORD dwCtrlType) {
+  if (dwCtrlType == CTRL_C_EVENT || dwCtrlType == CTRL_BREAK_EVENT) {
+    if (!PostQueuedCompletionStatus(ioport_, 0, 0, NULL))
+      Win32Fatal("PostQueuedCompletionStatus");
+    return TRUE;
+  }
+
+  return FALSE;
+}
+
+Subprocess *SubprocessSet::Add(const string& command) {
+  Subprocess *subprocess = new Subprocess;
+  if (!subprocess->Start(this, command)) {
+    delete subprocess;
+    return 0;
+  }
+  if (subprocess->child_)
+    running_.push_back(subprocess);
+  else
+    finished_.push(subprocess);
+  return subprocess;
+}
+
+bool SubprocessSet::DoWork() {
+  DWORD bytes_read;
+  Subprocess* subproc;
+  OVERLAPPED* overlapped;
+
+  if (!GetQueuedCompletionStatus(ioport_, &bytes_read, (PULONG_PTR)&subproc,
+                                 &overlapped, INFINITE)) {
+    if (GetLastError() != ERROR_BROKEN_PIPE)
+      Win32Fatal("GetQueuedCompletionStatus");
+  }
+
+  if (!subproc) // A NULL subproc indicates that we were interrupted and is
+                // delivered by NotifyInterrupted above.
+    return true;
+
+  subproc->OnPipeReady();
+
+  if (subproc->Done()) {
+    vector<Subprocess*>::iterator end =
+        std::remove(running_.begin(), running_.end(), subproc);
+    if (running_.end() != end) {
+      finished_.push(subproc);
+      running_.resize(end - running_.begin());
+    }
+  }
+
+  return false;
+}
+
+Subprocess* SubprocessSet::NextFinished() {
+  if (finished_.empty())
+    return NULL;
+  Subprocess* subproc = finished_.front();
+  finished_.pop();
+  return subproc;
+}
+
+void SubprocessSet::Clear() {
+  for (vector<Subprocess*>::iterator i = running_.begin();
+       i != running_.end(); ++i) {
+    if ((*i)->child_)
+      if (!GenerateConsoleCtrlEvent(CTRL_BREAK_EVENT, GetProcessId((*i)->child_)))
+        Win32Fatal("GenerateConsoleCtrlEvent");
+  }
+  for (vector<Subprocess*>::iterator i = running_.begin();
+       i != running_.end(); ++i)
+    delete *i;
+  running_.clear();
+}
+
+
+// Copyright 2011 Google Inc. 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,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+
+// Wrapper around cl that adds /showIncludes to command line, and uses that to
+// generate .d files that match the style from gcc -MD.
+//
+// /showIncludes is equivalent to -MD, not -MMD, that is, system headers are
+// included.
+
+
+#include <windows.h>
+#include <sstream>
+//#include "subprocess.h"
+//#include "util.h"
+
+// We don't want any wildcard expansion.
+// See http://msdn.microsoft.com/en-us/library/zay8tzh6(v=vs.85).aspx
+void _setargv() {}
+
+
+static void usage(const char* msg) {
+  Fatal("%s\n\nusage:\n"
+          "  cldeps "
+          "<source file> "
+          "<output path for *.d file> "
+          "<output path for *.obj file> "
+          "<prefix of /showIncludes> "
+          "<path to cl> "
+          "<rest of command ...>\n", msg);
+}
+
+static string trimLeadingSpace(const string& cmdline) {
+  int i = 0;
+  for (; cmdline[i] == ' '; ++i)
+    ;
+  return cmdline.substr(i);
+}
+
+static void doEscape(string& str, const string& search, const string& repl) {
+  string::size_type pos = 0;
+  while ((pos = str.find(search, pos)) != string::npos) {
+    str.replace(pos, search.size(), repl);
+    pos += repl.size();
+  }
+}
+
+// Strips one argument from the cmdline and returns it. "surrounding quotes"
+// are removed from the argument if there were any.
+static string getArg(string& cmdline) {
+  string ret;
+  bool in_quoted = false;
+  unsigned int i = 0;
+
+  cmdline = trimLeadingSpace(cmdline);
+
+  for (;; ++i) {
+    if (i >= cmdline.size())
+      usage("Couldn't parse arguments.");
+    if (!in_quoted && cmdline[i] == ' ')
+      break;
+    if (cmdline[i] == '"')
+      in_quoted = !in_quoted;
+  }
+
+  ret = cmdline.substr(0, i);
+  if (ret[0] == '"' && ret[i - 1] == '"')
+    ret = ret.substr(1, ret.size() - 2);
+  cmdline = cmdline.substr(i);
+  return ret;
+}
+
+static void parseCommandLine(LPTSTR wincmdline,
+        string& srcfile, string& dfile, string& objfile, string& prefix, string& clpath, string& rest) {
+  string cmdline(wincmdline);
+  /* self */ getArg(cmdline);
+  srcfile = getArg(cmdline);
+  std::string::size_type pos = srcfile.rfind("\\");
+  if (pos != string::npos) {
+    srcfile = srcfile.substr(pos + 1);
+  } else {
+    srcfile = "";
+  }
+  dfile = getArg(cmdline);
+  objfile = getArg(cmdline);
+  prefix = getArg(cmdline);
+  clpath = getArg(cmdline);
+  rest = trimLeadingSpace(cmdline);
+}
+
+static void outputDepFile(const string& dfile, const string& objfile,
+        vector<string>& incs) {
+
+  // strip duplicates
+  sort(incs.begin(), incs.end());
+  incs.erase(unique(incs.begin(), incs.end()), incs.end());
+
+  FILE* out = fopen(dfile.c_str(), "wb");
+
+  // FIXME should this be fatal or not? delete obj? delete d?
+  if (!out)
+    return;
+
+  fprintf(out, "%s: \\\n", objfile.c_str());
+  for (vector<string>::iterator i(incs.begin()); i != incs.end(); ++i) {
+    string tmp = *i;
+    doEscape(tmp, "\\", "\\\\");
+    doEscape(tmp, " ", "\\ ");
+    //doEscape(tmp, "(", "("); // TODO ninja cant read ( and )
+    //doEscape(tmp, ")", ")");
+    fprintf(out, "%s \\\n", tmp.c_str());
+  }
+
+  fprintf(out, "\n");
+  fclose(out);
+}
+
+
+bool startsWith(const std::string& str, const std::string& what) {
+  return str.compare(0, what.size(), what) == 0;
+}
+
+bool contains(const std::string& str, const std::string& what) {
+  return str.find(what) != std::string::npos;
+}
+
+int main() {
+
+  // Use the Win32 api instead of argc/argv so we can avoid interpreting the
+  // rest of command line after the .d and .obj. Custom parsing seemed
+  // preferable to the ugliness you get into in trying to re-escape quotes for
+  // subprocesses, so by avoiding argc/argv, the subprocess is called with
+  // the same command line verbatim.
+
+  string srcfile, dfile, objfile, prefix, clpath, rest;
+  parseCommandLine(GetCommandLine(), srcfile, dfile, objfile, prefix, clpath, rest);
+
+  //fprintf(stderr, "D: %s\n", dfile.c_str());
+  //fprintf(stderr, "OBJ: %s\n", objfile.c_str());
+  //fprintf(stderr, "CL: %s\n", clpath.c_str());
+  //fprintf(stderr, "REST: %s\n", rest.c_str());
+
+  SubprocessSet subprocs;
+  Subprocess* subproc = subprocs.Add(clpath + " /showIncludes " + rest);
+  if(!subproc)
+    return 2;
+
+  while ((subproc = subprocs.NextFinished()) == NULL) {
+    subprocs.DoWork();
+  }
+
+  bool success = subproc->Finish() == ExitSuccess;
+  string output = subproc->GetOutput();
+
+  delete subproc;
+
+  // process the include directives and output everything else
+  stringstream ss(output);
+  string line;
+  vector<string> includes;
+  bool isFirstLine = true; // cl prints always first the source filename
+  std::string sysHeadersCamel =    "Program Files (x86)\\Microsoft ";
+  std::string sysHeadersLower = "program files (x86)\\microsoft ";
+  while (getline(ss, line)) {
+    if (startsWith(line, prefix)) {
+       if (!contains(line, sysHeadersCamel) && !contains(line, sysHeadersLower)) {
+        string inc = trimLeadingSpace(line.substr(prefix.size()).c_str());
+        if (inc[inc.size() - 1] == '\r') // blech, stupid \r\n
+          inc = inc.substr(0, inc.size() - 1);
+        includes.push_back(inc);
+       }
+    } else {
+      if (!isFirstLine || !startsWith(line, srcfile)) {
+        fprintf(stdout, "%s\n", line.c_str());
+      } else {
+        isFirstLine = false;
+      }
+    }
+  }
+
+  if (!success)
+    return 3;
+
+  // don't update .d until/unless we succeed compilation
+  outputDepFile(dfile, objfile, includes);
+
+  return 0;
+}
diff --git a/Tests/BuildDepends/CMakeLists.txt b/Tests/BuildDepends/CMakeLists.txt
index aa32d67a00..5e36d11b44 100644
--- a/Tests/BuildDepends/CMakeLists.txt
+++ b/Tests/BuildDepends/CMakeLists.txt
@@ -28,6 +28,10 @@ function(help_xcode_depends)
   endif(HELP_XCODE)
 endfunction(help_xcode_depends)
 
+if("${CMAKE_GENERATOR}" MATCHES "Ninja")
+  set(HELP_NINJA 1) # TODO Why is this needed?
+endif()
+
 # The Intel compiler causes the MSVC linker to crash during
 # incremental linking, so avoid the /INCREMENTAL:YES flag.
 if(WIN32 AND "${CMAKE_CXX_COMPILER_ID}" MATCHES "Intel")
@@ -154,7 +158,7 @@ try_compile(RESULT
   OUTPUT_VARIABLE OUTPUT)
 
 # Xcode is in serious need of help here
-if(HELP_XCODE)
+if(HELP_XCODE OR HELP_NINJA)
   try_compile(RESULT 
     ${BuildDepends_BINARY_DIR}/Project
     ${BuildDepends_SOURCE_DIR}/Project
@@ -165,7 +169,7 @@ if(HELP_XCODE)
     ${BuildDepends_SOURCE_DIR}/Project
     testRebuild
     OUTPUT_VARIABLE OUTPUT)
-endif(HELP_XCODE)
+endif()
 
 message("Output from second build:\n${OUTPUT}")
 if(NOT RESULT)