Cross platform low level file IO wrappers

util/file/file_io_win.cc

Index: util/file/file_io_win.cc
diff --git a/util/synchronization/semaphore.cc b/util/file/file_io_win.cc
similarity index 44%
copy from util/synchronization/semaphore.cc
copy to util/file/file_io_win.cc
index d513fa0dd43981acc72b1ff155fa2d1e77616388..e6e865d1460b9911c00088d7090371d0fa514cbb 100644
--- a/util/synchronization/semaphore.cc
+++ b/util/file/file_io_win.cc
@@ -12,50 +12,39 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-#include "util/synchronization/semaphore.h"
+#include "util/file/file_io.h"
 
 #include "base/logging.h"
-#include "base/posix/eintr_wrapper.h"
+#include "base/numerics/safe_conversions.h"
 
 namespace crashpad {
 
-#if defined(OS_MACOSX)
+// TODO(scottmg): Handle > DWORD sized writes if necessary.
 
-Semaphore::Semaphore(int value)
-    : semaphore_(dispatch_semaphore_create(value)) {
-  CHECK(semaphore_) << "dispatch_semaphore_create";
+ssize_t ReadFile(HANDLE file, void* buffer, size_t size) {
+  DWORD size_dword = base::checked_cast<DWORD>(size);
+  DWORD bytes_read;
+  BOOL rv = ::ReadFile(file, buffer, size_dword, &bytes_read, NULL);
+  if (!rv)
+    return -1;
+  return bytes_read;
 }
 
-Semaphore::~Semaphore() {
-  dispatch_release(semaphore_);
+ssize_t WriteFile(HANDLE file, const void* buffer, size_t size) {
+  // TODO(scottmg): This might need to handle the limit for pipes across a
+  // network in the future.
+  DWORD size_dword = base::checked_cast<DWORD>(size);
+  DWORD bytes_written;
+  BOOL rv = ::WriteFile(file, buffer, size_dword, &bytes_written, NULL);
+  if (!rv)
+    return -1;
+  return bytes_written;
 }
 
-void Semaphore::Wait() {
-  CHECK_EQ(dispatch_semaphore_wait(semaphore_, DISPATCH_TIME_FOREVER), 0);
+bool LoggingCloseFile(HANDLE file) {
+  BOOL rv = ::CloseHandle(file);
+  PLOG_IF(ERROR, !rv) << "CloseHandle";
+  return rv;
 }
 
-void Semaphore::Signal() {
-  dispatch_semaphore_signal(semaphore_);
-}
-
-#else
-
-Semaphore::Semaphore(int value) {
-  PCHECK(sem_init(&semaphore_, 0, value) == 0) << "sem_init";
-}
-
-Semaphore::~Semaphore() {
-  PCHECK(sem_destroy(&semaphore_)) << "sem_destroy";
-}
-
-void Semaphore::Wait() {
-  PCHECK(HANDLE_EINTR(sem_wait(&semaphore_))) << "sem_wait";
-}
-
-void Semaphore::Signal() {
-  PCHECK(sem_post(&semaphore_)) << "sem_post";
-}
-
-#endif
-
 }  // namespace crashpad