Change the allocation of the stdout and stderr collected by Process.runSync

runtime/bin/process.h

 // 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.
 
 #ifndef BIN_PROCESS_H_
 #define BIN_PROCESS_H_
 
 #include "bin/builtin.h"
+#include "bin/io_buffer.h"
 #include "bin/thread.h"
 #include "platform/globals.h"
+#include "platform/utils.h"
 
 
 namespace dart {
 namespace bin {
 
 class ProcessResult {
  public:
-  ProcessResult()
-      : stdout_data_(NULL), stdout_length_(0),
-        stderr_data_(NULL), stderr_length_(0), exit_code_(0) {}
+  ProcessResult() : exit_code_(0) {}
 
-  void SetStdoutData(uint8_t* buffer, intptr_t length) {
-    stdout_data_ = buffer;
-    stdout_length_ = length;
+  void set_stdout_data(Dart_Handle stdout_data) {
+    stdout_data_ = stdout_data;
   }
-
-  void SetStderrData(uint8_t* buffer, intptr_t length) {
-    stderr_data_ = buffer;
-    stderr_length_ = length;
+  void set_stderr_data(Dart_Handle stderr_data) {
+    stderr_data_ = stderr_data;
   }
 
   void set_exit_code(intptr_t exit_code) { exit_code_ = exit_code; }
 
-  uint8_t* stdout_data() { return stdout_data_; }
-  intptr_t stdout_length() { return stdout_length_; }
-  uint8_t* stderr_data() { return stderr_data_; }
-  intptr_t stderr_length() { return stderr_length_; }
+  Dart_Handle stdout_data() { return stdout_data_; }
+  Dart_Handle stderr_data() { return stderr_data_; }
   intptr_t exit_code() { return exit_code_; }
 
  private:
-  uint8_t* stdout_data_;
-  intptr_t stdout_length_;
-  uint8_t* stderr_data_;
-  intptr_t stderr_length_;
+  Dart_Handle stdout_data_;
+  Dart_Handle stderr_data_;
   intptr_t exit_code_;
 
   DISALLOW_ALLOCATION();
 };
 
 
 class Process {
  public:
   // Start a new process providing access to stdin, stdout, stderr and
   // process exit streams.
@@ skipping 42 matching lines @@
                                              intptr_t pid);
 
  private:
   static int global_exit_code_;
   static dart::Mutex* global_exit_code_mutex_;
 
   DISALLOW_ALLOCATION();
   DISALLOW_IMPLICIT_CONSTRUCTORS(Process);
 };
 
+
+// Utility class for collecting the output when running a process
+// synchronously by using Process::Wait. This class is sub-classed in
+// the platform specific files to implement reading into the buffers
+// allocated.
+class BufferListBase {
+ protected:
+  static const intptr_t kBufferSize = 16 * 1024;
+
+  class BufferListNode {
+   public:
+    explicit BufferListNode(intptr_t size) {
+      data_ = new uint8_t[size];
+      if (data_ == NULL) FATAL("Allocation failed");
+      next_ = NULL;
+    }
+
+    ~BufferListNode() {
+      delete[] data_;
+    }
+
+    uint8_t* data_;
+    BufferListNode* next_;
+
+   private:
+    DISALLOW_IMPLICIT_CONSTRUCTORS(BufferListNode);
+  };
+
+ public:
+  BufferListBase() : head_(NULL), tail_(NULL), data_size_(0), free_size_(0) {}
+  ~BufferListBase() {
+    ASSERT(head_ == NULL);
+    ASSERT(tail_ == NULL);
+  }
+
+  // Returns the collected data as a Uint8List. If an error occours an
+  // error handle is returned.
+  Dart_Handle GetData() {
+    uint8_t* buffer;
+    intptr_t buffer_position = 0;
+    Dart_Handle result = IOBuffer::Allocate(data_size_, &buffer);
+    if (Dart_IsError(result)) {
+      Free();
+      return result;
+    }
+    for (BufferListNode* current = head_;
+         current != NULL;
+         current = current->next_) {
+      intptr_t to_copy = dart::Utils::Minimum(data_size_, kBufferSize);
+      memmove(buffer + buffer_position, current->data_, to_copy);
+      buffer_position += to_copy;
+      data_size_ -= to_copy;
+    }
+    ASSERT(data_size_ == 0);
+    Free();
+    return result;
+  }
+
+ protected:
+  void Allocate() {
+    ASSERT(free_size_ == 0);
+    BufferListNode* node = new BufferListNode(kBufferSize);
+    if (head_ == NULL) {
+      head_ = node;
+      tail_ = node;
+    } else {
+      ASSERT(tail_->next_ == NULL);
+      tail_->next_ = node;
+      tail_ = node;
+    }
+    free_size_ = kBufferSize;
+  }
+
+  void Free() {
+    for (BufferListNode* current = head_;
+         current != NULL;
+         current = current->next_) {
+    }
+    head_ = NULL;
+    tail_ = NULL;
+    data_size_ = 0;
+    free_size_ = 0;
+  }
+
+  // Linked list for data collected.
+  BufferListNode* head_;
+  BufferListNode* tail_;
+
+  // Number of bytes of data collected in the linked list.
+  intptr_t data_size_;
+
+  // Number of free bytes in the last node in the list.
+  intptr_t free_size_;
+};
+
 }  // namespace bin
 }  // namespace dart
 
 #endif  // BIN_PROCESS_H_