From 83cb156b6f77c11e2a2068e3b75b69c4eea2dfd2 Mon Sep 17 00:00:00 2001
From: Ryan <ry@tinyclouds.org>
Date: Sat, 20 Jun 2009 16:44:06 +0200
Subject: [PATCH] skelton of node.Process

---
 src/node.cc    |   2 +
 src/process.cc | 225 +++++++++++++++++++++++++++++++++++++++++++++++++
 src/process.h  |  45 ++++++++++
 wscript        |   1 +
 4 files changed, 273 insertions(+)
 create mode 100644 src/process.cc
 create mode 100644 src/process.h

diff --git a/src/node.cc b/src/node.cc
index 07384838b7..6036e158b8 100644
--- a/src/node.cc
+++ b/src/node.cc
@@ -4,6 +4,7 @@
 #include "file.h"
 #include "http.h"
 #include "timer.h"
+#include "process.h"
 #include "constants.h"
 
 #include "natives.h" 
@@ -302,6 +303,7 @@ Load (int argc, char *argv[])
   NODE_SET_METHOD(node_obj, "reallyExit", node_exit);
 
   Timer::Initialize(node_obj);
+  Process::Initialize(node_obj);
 
   DefineConstants(node_obj);
 
diff --git a/src/process.cc b/src/process.cc
new file mode 100644
index 0000000000..fddc4ca207
--- /dev/null
+++ b/src/process.cc
@@ -0,0 +1,225 @@
+#include "node.h"
+#include "process.h"
+
+#include <assert.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/types.h>
+
+using namespace v8;
+using namespace node;
+
+Persistent<FunctionTemplate> Process::constructor_template;
+
+void
+Process::Initialize (Handle<Object> target)
+{
+  HandleScope scope;
+
+  Local<FunctionTemplate> t = FunctionTemplate::New(Process::New);
+  constructor_template = Persistent<FunctionTemplate>::New(t);
+  constructor_template->InstanceTemplate()->SetInternalFieldCount(1);
+
+#if 0
+  NODE_SET_PROTOTYPE_METHOD(constructor_template, "start", Timer::Start);
+  NODE_SET_PROTOTYPE_METHOD(constructor_template, "stop", Timer::Stop);
+#endif 
+
+  target->Set(String::NewSymbol("Process"), constructor_template->GetFunction());
+}
+
+Handle<Value>
+Process::New (const Arguments& args)
+{
+  if (args.Length() == 0) return Undefined();
+
+  HandleScope scope;
+
+  String::Utf8Value command(args[0]->ToString());
+
+  Process *p = new Process(args.Holder());
+  ObjectWrap::InformV8ofAllocation(p);
+
+  int r = p->Spawn(*command);
+  if (r != 0) {
+    return ThrowException(String::New("Error spawning"));
+  }
+
+  return args.This();
+}
+
+Process::Process (Handle<Object> handle)
+  : ObjectWrap(handle)
+{
+  ev_init(&stdout_watcher_, Process::OnOutput);
+  stdout_watcher_.data = this;
+
+  ev_init(&stderr_watcher_, Process::OnError);
+  stderr_watcher_.data = this;
+
+  ev_init(&stdin_watcher_, Process::OnWritable);
+  stdin_watcher_.data = this;
+
+  ev_init(&child_watcher_, Process::OnCHLD);
+  child_watcher_.data = this;
+
+  stdout_pipe_[0] = -1;
+  stdout_pipe_[1] = -1;
+  stderr_pipe_[0] = -1;
+  stderr_pipe_[1] = -1;
+  stdin_pipe_[0] = -1;
+  stdin_pipe_[1] = -1;
+
+  pid_ = 0; 
+}
+
+Process::~Process ()
+{
+  Shutdown();
+}
+
+void
+Process::Shutdown () 
+{
+  if (stdout_pipe_[0] >= 0) close(stdout_pipe_[0]);
+  if (stdout_pipe_[1] >= 0) close(stdout_pipe_[1]);
+
+  if (stderr_pipe_[0] >= 0) close(stderr_pipe_[0]);
+  if (stderr_pipe_[1] >= 0) close(stderr_pipe_[1]);
+
+  if (stdin_pipe_[0] >= 0) close(stdin_pipe_[0]);
+  if (stdin_pipe_[1] >= 0) close(stdin_pipe_[1]);
+
+  stdout_pipe_[0] = -1;
+  stdout_pipe_[1] = -1;
+  stderr_pipe_[0] = -1;
+  stderr_pipe_[1] = -1;
+  stdin_pipe_[0] = -1;
+  stdin_pipe_[1] = -1;
+
+  ev_io_stop(EV_DEFAULT_UC_ &stdout_watcher_);
+  ev_io_stop(EV_DEFAULT_UC_ &stderr_watcher_);
+  ev_io_stop(EV_DEFAULT_UC_ &stdin_watcher_);
+
+  ev_child_stop(EV_DEFAULT_UC_ &child_watcher_);
+  /* XXX Kill the PID? */
+  pid_ = 0;
+
+  Detach();
+}
+
+static int
+SetNonBlocking (int fd)
+{
+  int flags = fcntl(fd, F_GETFL, 0);
+  int r = fcntl(fd, F_SETFL, flags | O_NONBLOCK);
+  if (r != 0) {
+    perror("SetNonBlocking()");
+  }
+  return r;
+}
+
+int
+Process::Spawn (const char *command)
+{
+  assert(pid_ == 0);
+  assert(stdout_pipe_[0] == -1);
+  assert(stdout_pipe_[1] == -1);
+  assert(stderr_pipe_[0] == -1);
+  assert(stderr_pipe_[1] == -1);
+  assert(stdin_pipe_[0] == -1);
+  assert(stdin_pipe_[1] == -1);
+
+  /* An implementation of popen(), basically */
+  if (pipe(stdout_pipe_) < 0) {
+    perror("pipe()");
+    return -1;
+  }
+
+  if (pipe(stderr_pipe_) < 0) {
+    perror("pipe()");
+    return -2;
+  }
+
+  if (pipe(stdin_pipe_) < 0) {
+    perror("pipe()");
+    return -3;
+  }
+
+  switch (pid_ = vfork()) {
+    case -1: // Error.
+      Shutdown();
+      return -4;
+
+    case 0: // Child.
+      close(stdout_pipe_[0]); // close read end 
+      dup2(stdout_pipe_[1], STDOUT_FILENO);
+
+      close(stderr_pipe_[0]); // close read end 
+      dup2(stderr_pipe_[1], STDERR_FILENO);
+
+      close(stdin_pipe_[1]); // close write end 
+      dup2(stdin_pipe_[0],  STDIN_FILENO);
+
+      execl("/bin/sh", "-c", command, (char *)NULL);
+      _exit(127);
+  }
+
+  // Parent.
+
+  ev_child_set(&child_watcher_, pid_, 0);
+  ev_child_start(EV_DEFAULT_UC_ &child_watcher_);
+
+  SetNonBlocking(stdout_pipe_[0]);
+  SetNonBlocking(stderr_pipe_[0]);
+  SetNonBlocking(stdin_pipe_[1]);
+
+  ev_io_set(&stdout_watcher_, stdout_pipe_[0], EV_READ);    
+  ev_io_set(&stderr_watcher_, stderr_pipe_[0], EV_READ);    
+  ev_io_set(&stdin_watcher_, stdin_pipe_[1], EV_WRITE);    
+
+  ev_io_start(EV_DEFAULT_UC_ &stdout_watcher_);
+  ev_io_start(EV_DEFAULT_UC_ &stderr_watcher_);
+  ev_io_start(EV_DEFAULT_UC_ &stdin_watcher_);
+
+  close(stdout_pipe_[1]); // close write end 
+  close(stderr_pipe_[1]); // close write end 
+  close(stdin_pipe_[0]);  // close read end 
+
+  stdout_pipe_[1] = -1;
+  stderr_pipe_[1] = -1;
+  stdin_pipe_[0] = -1;
+
+  Attach();
+
+  return 0;
+}
+
+void 
+Process::OnOutput (EV_P_ ev_io *watcher, int revents)
+{
+  Process *process = static_cast<Process*>(watcher->data);
+  assert(revents == EV_READ);
+}
+
+void 
+Process::OnError (EV_P_ ev_io *watcher, int revents)
+{
+  Process *process = static_cast<Process*>(watcher->data);
+  assert(revents == EV_READ);
+}
+
+void 
+Process::OnWritable (EV_P_ ev_io *watcher, int revents)
+{
+  Process *process = static_cast<Process*>(watcher->data);
+  assert(revents == EV_WRITE);
+}
+
+void 
+Process::OnCHLD (EV_P_ ev_child *watcher, int revents)
+{
+  ev_child_stop(EV_A_ watcher);
+  Process *process = static_cast<Process*>(watcher->data);
+  assert(revents == EV_CHILD);
+}
diff --git a/src/process.h b/src/process.h
new file mode 100644
index 0000000000..5e2a25eb76
--- /dev/null
+++ b/src/process.h
@@ -0,0 +1,45 @@
+#ifndef node_process_h
+#define node_process_h
+
+#include "node.h"
+#include <v8.h>
+#include <ev.h>
+
+namespace node {
+
+class Process : ObjectWrap {
+ public:
+  static void Initialize (v8::Handle<v8::Object> target);
+
+  virtual size_t size (void) { return sizeof(Process); }
+
+ protected:
+  static v8::Persistent<v8::FunctionTemplate> constructor_template;
+  static v8::Handle<v8::Value> New (const v8::Arguments& args);
+
+  Process(v8::Handle<v8::Object> handle);
+  ~Process();
+
+  void Shutdown ();
+  int Spawn (const char *command);
+
+ private:
+  static void OnOutput (EV_P_ ev_io *watcher, int revents);
+  static void OnError (EV_P_ ev_io *watcher, int revents);
+  static void OnWritable (EV_P_ ev_io *watcher, int revents);
+  static void OnCHLD (EV_P_ ev_child *watcher, int revents);
+
+  ev_io stdout_watcher_;
+  ev_io stderr_watcher_;
+  ev_io stdin_watcher_;
+  ev_child child_watcher_;
+
+  int stdout_pipe_[2];
+  int stderr_pipe_[2];
+  int stdin_pipe_[2];
+
+  pid_t pid_;
+};
+
+} // namespace node 
+#endif //  node_process_h
diff --git a/wscript b/wscript
index 8d49a88118..ce85c400b5 100644
--- a/wscript
+++ b/wscript
@@ -158,6 +158,7 @@ def build(bld):
     src/net.cc
     src/file.cc
     src/timer.cc
+    src/process.cc
     src/constants.cc
   """
   node.includes = """