DXR is a code search and navigation tool aimed at making sense of large projects. It supports full-text and regex searches as well as structural queries.

Header

Mercurial (d1ed7de67f5a)

VCS Links

Line Code
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138
/* 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/. */

#include "FileDescriptorUtils.h"

#include "nsIEventTarget.h"

#include "nsCOMPtr.h"
#include "nsDebug.h"
#include "nsNetCID.h"
#include "nsServiceManagerUtils.h"
#include "nsThreadUtils.h"
#include "prio.h"
#include "private/pprio.h"

#include <errno.h>
#ifdef XP_WIN
#include <io.h>
#else
#include <unistd.h>
#endif

using mozilla::ipc::CloseFileRunnable;

#ifdef DEBUG

CloseFileRunnable::CloseFileRunnable(const FileDescriptor& aFileDescriptor)
: mFileDescriptor(aFileDescriptor)
{
  MOZ_ASSERT(aFileDescriptor.IsValid());
}

#endif // DEBUG

CloseFileRunnable::~CloseFileRunnable()
{
  if (mFileDescriptor.IsValid()) {
    // It's probably safer to take the main thread IO hit here rather than leak
    // the file descriptor.
    CloseFile();
  }
}

NS_IMPL_ISUPPORTS(CloseFileRunnable, nsIRunnable)

void
CloseFileRunnable::Dispatch()
{
  nsCOMPtr<nsIEventTarget> eventTarget =
    do_GetService(NS_STREAMTRANSPORTSERVICE_CONTRACTID);
  NS_ENSURE_TRUE_VOID(eventTarget);

  nsresult rv = eventTarget->Dispatch(this, NS_DISPATCH_NORMAL);
  NS_ENSURE_SUCCESS_VOID(rv);
}

void
CloseFileRunnable::CloseFile()
{
  // It's possible for this to happen on the main thread if the dispatch to the
  // stream service fails so we can't assert the thread on which we're running.

  MOZ_ASSERT(mFileDescriptor.IsValid());

  PRFileDesc* fd =
    PR_ImportFile(PROsfd(mFileDescriptor.PlatformHandle()));
  NS_WARN_IF_FALSE(fd, "Failed to import file handle!");

  mFileDescriptor = FileDescriptor();

  if (fd) {
    PR_Close(fd);
    fd = nullptr;
  }
}

NS_IMETHODIMP
CloseFileRunnable::Run()
{
  MOZ_ASSERT(!NS_IsMainThread());

  CloseFile();
  return NS_OK;
}

namespace mozilla {
namespace ipc {

FILE*
FileDescriptorToFILE(const FileDescriptor& aDesc,
                     const char* aOpenMode)
{
  // Debug builds check whether the handle was "used", even if it's
  // invalid, so that needs to happen first.
  FileDescriptor::PlatformHandleType handle = aDesc.PlatformHandle();
  if (!aDesc.IsValid()) {
    errno = EBADF;
    return nullptr;
  }
#ifdef XP_WIN
  int fd = _open_osfhandle(reinterpret_cast<intptr_t>(handle), 0);
  if (fd == -1) {
    CloseHandle(handle);
    return nullptr;
  }
#else
  int fd = handle;
#endif
  FILE* file = fdopen(fd, aOpenMode);
  if (!file) {
    int saved_errno = errno;
    close(fd);
    errno = saved_errno;
  }
  return file;
}

FileDescriptor
FILEToFileDescriptor(FILE* aStream)
{
  if (!aStream) {
    errno = EBADF;
    return FileDescriptor();
  }
#ifdef XP_WIN
  int fd = _fileno(aStream);
  if (fd == -1) {
    return FileDescriptor();
  }
  return FileDescriptor(reinterpret_cast<HANDLE>(_get_osfhandle(fd)));
#else
  return FileDescriptor(fileno(aStream));
#endif
}

} // namespace ipc
} // namespace mozilla