Add Process.runSync for running processe synchronously.

runtime/bin/process_macos.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "platform/globals.h"
 #if defined(TARGET_OS_MACOS)
 
 #include "bin/process.h"
 
 #include <errno.h>  // NOLINT
@@ skipping 549 matching lines @@
   VOID_TEMP_FAILURE_RETRY(close(write_out[0]));
   FDUtils::SetNonBlocking(read_err[0]);
   *err = read_err[0];
   VOID_TEMP_FAILURE_RETRY(close(read_err[1]));
 
   *id = pid;
   return 0;
 }
 
 
+static bool ReadProcessBuffer(uint8_t** buffer,
+                              intptr_t* buffer_length,
+                              intptr_t available,
+                              int fd) {
+  uint8_t* tmp = new uint8_t[*buffer_length + available];
+  if (tmp == NULL) FATAL("Allocation failed");
+  memmove(tmp, *buffer, *buffer_length);
+  delete[] *buffer;
+  *buffer = tmp;
+  intptr_t bytes = TEMP_FAILURE_RETRY(read(
+      fd,
+      reinterpret_cast<void*>(*buffer + *buffer_length),
+      available));
+  if (bytes < 0) return false;
+  *buffer_length += bytes;
+  return true;
+}
+
+
+static bool CloseProcessBuffers(struct pollfd fds[3]) {
+  int e = errno;
+  VOID_TEMP_FAILURE_RETRY(close(fds[0].fd));
+  VOID_TEMP_FAILURE_RETRY(close(fds[1].fd));
+  VOID_TEMP_FAILURE_RETRY(close(fds[2].fd));
+  errno = e;
+  return false;
+}
+
+
+bool Process::Wait(intptr_t pid,
+                   intptr_t in,
+                   intptr_t out,
+                   intptr_t err,
+                   intptr_t exit_event,
+                   ProcessResult* result) {
+  // Close input to the process right away.
+  VOID_TEMP_FAILURE_RETRY(close(in));
+
+  uint8_t* out_data = NULL;
+  intptr_t out_data_length = 0;
+  uint8_t* err_data = NULL;
+  intptr_t err_data_length = 0;
+  union {
+    uint8_t bytes[8];
+    int32_t ints[2];
+  } exit_code_data;
+
+  struct pollfd fds[3];
+  fds[0].fd = out;
+  fds[1].fd = err;
+  fds[2].fd = exit_event;
+
+  for (int i = 0; i < 3; i++) {
+    fds[i].events = POLLIN;
+  }
+
+  int alive = 3;
+  while (alive > 0) {
+    if (TEMP_FAILURE_RETRY(poll(fds, alive, -1)) <= 0) {
+      return CloseProcessBuffers(fds);
+    }
+    for (int i = 0; i < alive; i++) {
+      if (fds[i].revents & POLLIN) {
+        intptr_t avail = FDUtils::AvailableBytes(fds[i].fd);
+        // On Mac OS POLLIN can be set with zero available
+        // bytes. POLLHUP is most likely also set in this case.
+        if (avail > 0) {
+          if (fds[i].fd == out) {
+            if (!ReadProcessBuffer(&out_data, &out_data_length, avail, out)) {
+              return CloseProcessBuffers(fds);
+            }
+          } else if (fds[i].fd == err) {
+            if (!ReadProcessBuffer(&err_data, &err_data_length, avail, err)) {
+              return CloseProcessBuffers(fds);
+            }
+          } else if (fds[i].fd == exit_event) {
+            intptr_t avail = FDUtils::AvailableBytes(fds[i].fd);
+            if (avail == 8) {
+              intptr_t bytes = 0;
+              do {
+                intptr_t b = TEMP_FAILURE_RETRY(read(fds[i].fd,
+                                                     exit_code_data.bytes, 8));

[Bill Hesse, 2013/08/09 15:32:23]

Ditto - + bytes

[Søren Gjesse, 2013/08/12 06:52:38]

Removed the loop here as well.

+                if (b > 0) {
+                  bytes += b;
+                } else {
+                  return CloseProcessBuffers(fds);
+                }
+              } while (bytes < 8);
+            }
+          } else {
+            UNREACHABLE();
+          }
+          continue;
+        }
+      }
+
+      if (fds[i].revents & POLLHUP) {
+        VOID_TEMP_FAILURE_RETRY(close(fds[i].fd));
+        alive--;
+        if (i < alive) {
+          fds[i] = fds[alive];
+        }
+      }
+    }
+  }
+
+  // All handles closed and all data read.
+  result->SetStdoutData(out_data, out_data_length);
+  result->SetStderrData(err_data, err_data_length);
+
+  // Calculate the exit code.
+  intptr_t exit_code = exit_code_data.ints[0];
+  intptr_t negative = exit_code_data.ints[1];
+  if (negative) exit_code = -exit_code;
+  result->set_exit_code(exit_code);
+
+  return true;
+}
+
+
 bool Process::Kill(intptr_t id, int signal) {
   return (TEMP_FAILURE_RETRY(kill(id, signal)) != -1);
 }
 
 
 void Process::TerminateExitCodeHandler() {
   ExitCodeHandler::TerminateExitCodeThread();
 }
 
 
 intptr_t Process::CurrentProcessId() {
   return static_cast<intptr_t>(getpid());
 }
 
 }  // namespace bin
 }  // namespace dart
 
 #endif  // defined(TARGET_OS_MACOS)