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#ifdef __MINGW32__
# include <node_child_process_win32.cc>
#endif
#ifdef __POSIX__
// Copyright 2009 Ryan Dahl <ry@tinyclouds.org>
#include <node_child_process.h>
#include <node.h>
#include <assert.h>
#include <string.h>
#include <stdlib.h>
#include <errno.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/types.h>
#if defined(__FreeBSD__ ) || defined(__OpenBSD__)
#include <sys/wait.h>
#endif
# ifdef __APPLE__
# include <crt_externs.h>
# define environ (*_NSGetEnviron())
# else
extern char **environ;
# endif
namespace node {
using namespace v8;
static Persistent<String> pid_symbol;
static Persistent<String> onexit_symbol;
// TODO share with other modules
static inline 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;
}
static inline int SetCloseOnExec(int fd) {
int flags = fcntl(fd, F_GETFD, 0);
int r = fcntl(fd, F_SETFD, flags | FD_CLOEXEC);
if (r != 0) {
perror("SetCloseOnExec()");
}
return r;
}
static inline int ResetFlags(int fd) {
int flags = fcntl(fd, F_GETFL, 0);
// blocking
int r = fcntl(fd, F_SETFL, flags & ~O_NONBLOCK);
flags = fcntl(fd, F_GETFD, 0);
// unset the CLOEXEC
fcntl(fd, F_SETFD, flags & ~FD_CLOEXEC);
return r;
}
void ChildProcess::Initialize(Handle<Object> target) {
HandleScope scope;
Local<FunctionTemplate> t = FunctionTemplate::New(ChildProcess::New);
t->InstanceTemplate()->SetInternalFieldCount(1);
t->SetClassName(String::NewSymbol("ChildProcess"));
pid_symbol = NODE_PSYMBOL("pid");
onexit_symbol = NODE_PSYMBOL("onexit");
NODE_SET_PROTOTYPE_METHOD(t, "spawn", ChildProcess::Spawn);
NODE_SET_PROTOTYPE_METHOD(t, "kill", ChildProcess::Kill);
target->Set(String::NewSymbol("ChildProcess"), t->GetFunction());
}
Handle<Value> ChildProcess::New(const Arguments& args) {
HandleScope scope;
ChildProcess *p = new ChildProcess();
p->Wrap(args.Holder());
return args.This();
}
// This is an internal function. The third argument should be an array
// of key value pairs seperated with '='.
Handle<Value> ChildProcess::Spawn(const Arguments& args) {
HandleScope scope;
if (args.Length() < 3 ||
!args[0]->IsString() ||
!args[1]->IsArray() ||
!args[2]->IsString() ||
!args[3]->IsArray()) {
return ThrowException(Exception::Error(String::New("Bad argument.")));
}
ChildProcess *child = ObjectWrap::Unwrap<ChildProcess>(args.Holder());
String::Utf8Value file(args[0]->ToString());
int i;
// Copy second argument args[1] into a c-string array called argv.
// The array must be null terminated, and the first element must be
// the name of the executable -- hence the complication.
Local<Array> argv_handle = Local<Array>::Cast(args[1]);
int argc = argv_handle->Length();
int argv_length = argc + 1 + 1;
char **argv = new char*[argv_length]; // heap allocated to detect errors
argv[0] = strdup(*file); // + 1 for file
argv[argv_length-1] = NULL; // + 1 for NULL;
for (i = 0; i < argc; i++) {
String::Utf8Value arg(argv_handle->Get(Integer::New(i))->ToString());
argv[i+1] = strdup(*arg);
}
// Copy third argument, args[2], into a c-string called cwd.
String::Utf8Value arg(args[2]->ToString());
char *cwd = strdup(*arg);
// Copy fourth argument, args[3], into a c-string array called env.
Local<Array> env_handle = Local<Array>::Cast(args[3]);
int envc = env_handle->Length();
char **env = new char*[envc+1]; // heap allocated to detect errors
env[envc] = NULL;
for (int i = 0; i < envc; i++) {
String::Utf8Value pair(env_handle->Get(Integer::New(i))->ToString());
env[i] = strdup(*pair);
}
int custom_fds[3] = { -1, -1, -1 };
if (args[4]->IsArray()) {
// Set the custom file descriptor values (if any) for the child process
Local<Array> custom_fds_handle = Local<Array>::Cast(args[4]);
int custom_fds_len = custom_fds_handle->Length();
for (int i = 0; i < custom_fds_len; i++) {
if (custom_fds_handle->Get(i)->IsUndefined()) continue;
Local<Integer> fd = custom_fds_handle->Get(i)->ToInteger();
custom_fds[i] = fd->Value();
}
}
int fds[3];
int r = child->Spawn(argv[0], argv, cwd, env, fds, custom_fds);
for (i = 0; i < argv_length; i++) free(argv[i]);
delete [] argv;
free(cwd);
for (i = 0; i < envc; i++) free(env[i]);
delete [] env;
if (r != 0) {
return ThrowException(Exception::Error(String::New("Error spawning")));
}
Local<Array> a = Array::New(3);
assert(fds[0] >= 0);
a->Set(0, Integer::New(fds[0])); // stdin
assert(fds[1] >= 0);
a->Set(1, Integer::New(fds[1])); // stdout
assert(fds[2] >= 0);
a->Set(2, Integer::New(fds[2])); // stderr
return scope.Close(a);
}
Handle<Value> ChildProcess::Kill(const Arguments& args) {
HandleScope scope;
ChildProcess *child = ObjectWrap::Unwrap<ChildProcess>(args.Holder());
assert(child);
if (child->pid_ < 1) {
return ThrowException(Exception::Error(String::New("No such process")));
}
int sig = SIGTERM;
if (args.Length() > 0) {
if (args[0]->IsNumber()) {
sig = args[0]->Int32Value();
} else {
return ThrowException(Exception::Error(String::New("Bad argument.")));
}
}
if (child->Kill(sig) != 0) {
return ThrowException(Exception::Error(String::New(strerror(errno))));
}
return Undefined();
}
void ChildProcess::Stop() {
if (ev_is_active(&child_watcher_)) {
ev_child_stop(EV_DEFAULT_UC_ &child_watcher_);
Unref();
}
// Don't kill the PID here. We want to allow for killing the parent
// process and reparenting to initd. This is perhaps not going the best
// technique for daemonizing, but I don't want to rule it out.
pid_ = -1;
}
// Note that args[0] must be the same as the "file" param. This is an
// execvp() requirement.
//
int ChildProcess::Spawn(const char *file,
char *const args[],
const char *cwd,
char **env,
int stdio_fds[3],
int custom_fds[3]) {
HandleScope scope;
assert(pid_ == -1);
assert(!ev_is_active(&child_watcher_));
int stdin_pipe[2], stdout_pipe[2], stderr_pipe[2];
/* An implementation of popen(), basically */
if ((custom_fds[0] == -1 && pipe(stdin_pipe) < 0) ||
(custom_fds[1] == -1 && pipe(stdout_pipe) < 0) ||
(custom_fds[2] == -1 && pipe(stderr_pipe) < 0)) {
perror("pipe()");
return -1;
}
// Set the close-on-exec FD flag
if (custom_fds[0] == -1) {
SetCloseOnExec(stdin_pipe[0]);
SetCloseOnExec(stdin_pipe[1]);
}
if (custom_fds[1] == -1) {
SetCloseOnExec(stdout_pipe[0]);
SetCloseOnExec(stdout_pipe[1]);
}
if (custom_fds[2] == -1) {
SetCloseOnExec(stderr_pipe[0]);
SetCloseOnExec(stderr_pipe[1]);
}
// Save environ in the case that we get it clobbered
// by the child process.
char **save_our_env = environ;
switch (pid_ = vfork()) {
case -1: // Error.
Stop();
return -4;
case 0: // Child.
if (custom_fds[0] == -1) {
close(stdin_pipe[1]); // close write end
dup2(stdin_pipe[0], STDIN_FILENO);
} else {
ResetFlags(custom_fds[0]);
dup2(custom_fds[0], STDIN_FILENO);
}
if (custom_fds[1] == -1) {
close(stdout_pipe[0]); // close read end
dup2(stdout_pipe[1], STDOUT_FILENO);
} else {
ResetFlags(custom_fds[1]);
dup2(custom_fds[1], STDOUT_FILENO);
}
if (custom_fds[2] == -1) {
close(stderr_pipe[0]); // close read end
dup2(stderr_pipe[1], STDERR_FILENO);
} else {
ResetFlags(custom_fds[2]);
dup2(custom_fds[2], STDERR_FILENO);
}
if (strlen(cwd) && chdir(cwd)) {
perror("chdir()");
_exit(127);
}
environ = env;
execvp(file, args);
perror("execvp()");
_exit(127);
}
// Parent.
// Restore environment.
environ = save_our_env;
ev_child_set(&child_watcher_, pid_, 0);
ev_child_start(EV_DEFAULT_UC_ &child_watcher_);
Ref();
handle_->Set(pid_symbol, Integer::New(pid_));
if (custom_fds[0] == -1) {
close(stdin_pipe[0]);
stdio_fds[0] = stdin_pipe[1];
SetNonBlocking(stdin_pipe[1]);
} else {
stdio_fds[0] = custom_fds[0];
}
if (custom_fds[1] == -1) {
close(stdout_pipe[1]);
stdio_fds[1] = stdout_pipe[0];
SetNonBlocking(stdout_pipe[0]);
} else {
stdio_fds[1] = custom_fds[1];
}
if (custom_fds[2] == -1) {
close(stderr_pipe[1]);
stdio_fds[2] = stderr_pipe[0];
SetNonBlocking(stderr_pipe[0]);
} else {
stdio_fds[2] = custom_fds[2];
}
return 0;
}
void ChildProcess::OnExit(int status) {
HandleScope scope;
pid_ = -1;
Stop();
handle_->Set(pid_symbol, Null());
Local<Value> onexit_v = handle_->Get(onexit_symbol);
assert(onexit_v->IsFunction());
Local<Function> onexit = Local<Function>::Cast(onexit_v);
TryCatch try_catch;
Local<Value> argv[2];
if (WIFEXITED(status)) {
argv[0] = Integer::New(WEXITSTATUS(status));
} else {
argv[0] = Local<Value>::New(Null());
}
if (WIFSIGNALED(status)) {
argv[1] = String::NewSymbol(signo_string(WTERMSIG(status)));
} else {
argv[1] = Local<Value>::New(Null());
}
onexit->Call(handle_, 2, argv);
if (try_catch.HasCaught()) {
FatalException(try_catch);
}
}
int ChildProcess::Kill(int sig) {
if (pid_ < 1) return -1;
return kill(pid_, sig);
}
} // namespace node
NODE_MODULE(node_child_process, node::ChildProcess::Initialize);
#endif // __POSIX__
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