Module: PhusionPassenger::NativeSupport

Defined in:
ext/ruby/passenger_native_support.c

Defined Under Namespace

Classes: FileSystemWatcher

Constant Summary collapse

UNIX_PATH_MAX =

The maximum length of a Unix socket path, including terminating null.

INT2NUM(sizeof(addr.sun_path))
SSIZE_MAX =

The maximum size of the data that may be passed to #writev.

LL2NUM(SSIZE_MAX)

Class Method Summary collapse

Class Method Details

.close_all_file_descriptors(exceptions) ⇒ Object

Close all file descriptors, except those given in the exceptions array. For example, the following would close all file descriptors except standard input (0) and standard output (1).

close_all_file_descriptors([0, 1])



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# File 'ext/ruby/passenger_native_support.c', line 273

static VALUE
close_all_file_descriptors(VALUE self, VALUE exceptions) {
	long i, j;
	
	for (i = sysconf(_SC_OPEN_MAX) - 1; i >= 0; i--) {
		int is_exception = 0;
		for (j = 0; j < RARRAY_LEN(exceptions) && !is_exception; j++) {
			long fd = NUM2INT(rb_ary_entry(exceptions, j));
			is_exception = i == fd;
		}
		if (!is_exception) {
			close((int) i);
		}
	}
	return Qnil;
}

.create_unix_socket(filename, backlog) ⇒ Object

Create a SOCK_STREAM server Unix socket. Unlike Ruby’s UNIXServer class, this function is also able to create Unix sockets on the abstract namespace by prepending the filename with a null byte.

  • filename (string): The filename of the Unix socket to create.

  • backlog (integer): The backlog to use for listening on the socket.

  • Returns: The file descriptor of the created Unix socket, as an integer.

  • Raises SystemCallError if something went wrong.



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# File 'ext/ruby/passenger_native_support.c', line 223

static VALUE
create_unix_socket(VALUE self, VALUE filename, VALUE backlog) {
	int fd, ret;
	struct sockaddr_un addr;
	const char *filename_str;
	long filename_length;
	
	filename_str = RSTRING_PTR(filename);
	filename_length = RSTRING_LEN(filename);
	
	fd = socket(PF_UNIX, SOCK_STREAM, 0);
	if (fd == -1) {
		rb_sys_fail("Cannot create a Unix socket");
		return Qnil;
	}
	
	addr.sun_family = AF_UNIX;
	memcpy(addr.sun_path, filename_str,
		MIN((long) filename_length, (long) sizeof(addr.sun_path)));
	addr.sun_path[sizeof(addr.sun_path) - 1] = '\0';
	
	ret = bind(fd, (const struct sockaddr *) &addr, sizeof(addr));
	if (ret == -1) {
		int e = errno;
		close(fd);
		errno = e;
		rb_sys_fail("Cannot bind Unix socket");
		return Qnil;
	}
	
	ret = listen(fd, NUM2INT(backlog));
	if (ret == -1) {
		int e = errno;
		close(fd);
		errno = e;
		rb_sys_fail("Cannot listen on Unix socket");
		return Qnil;
	}
	return INT2NUM(fd);
}

.disable_stdio_buffering ⇒ Object

Disables any kind of buffering on the C stdout and stderr variables, so that fprintf() on stdout and stderr have immediate effect.



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# File 'ext/ruby/passenger_native_support.c', line 296

static VALUE
disable_stdio_buffering(VALUE self) {
	setvbuf(stdout, NULL, _IONBF, 0);
	setvbuf(stderr, NULL, _IONBF, 0);
	return Qnil;
}

.process_times ⇒ Object 



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# File 'ext/ruby/passenger_native_support.c', line 609

static VALUE
process_times(VALUE self) {
	struct rusage usage;
	unsigned long long utime, stime;
	
	if (getrusage(RUSAGE_SELF, &usage) == -1) {
		rb_sys_fail("getrusage()");
	}
	
	utime = (unsigned long long) usage.ru_utime.tv_sec * 1000000 + usage.ru_utime.tv_usec;
	stime = (unsigned long long) usage.ru_stime.tv_sec * 1000000 + usage.ru_stime.tv_usec;
	return rb_struct_new(S_ProcessTimes, rb_ull2inum(utime), rb_ull2inum(stime));
}

.recv_fd(socket_fd) ⇒ Object

Receive a file descriptor from the given Unix socket. Returns the received file descriptor as an integer. Raises SystemCallError if something went wrong.

You do not have call this method directly. A convenience wrapper is provided by IO#recv_io.



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# File 'ext/ruby/passenger_native_support.c', line 156

static VALUE
recv_fd(VALUE self, VALUE socket_fd) {
	struct msghdr msg;
	struct iovec vec;
	char dummy[1];
	#if defined(__APPLE__) || defined(__SOLARIS__) || defined(__arm__)
		// File descriptor passing macros (CMSG_*) seem to be broken
		// on 64-bit MacOS X. This structure works around the problem.
		struct {
			struct cmsghdr header;
			int fd;
		} control_data;
		#define EXPECTED_CMSG_LEN sizeof(control_data)
	#else
		char control_data[CMSG_SPACE(sizeof(int))];
		#define EXPECTED_CMSG_LEN CMSG_LEN(sizeof(int))
	#endif
	struct cmsghdr *control_header;

	msg.msg_name    = NULL;
	msg.msg_namelen = 0;
	
	dummy[0]       = '\0';
	vec.iov_base   = dummy;
	vec.iov_len    = sizeof(dummy);
	msg.msg_iov    = &vec;
	msg.msg_iovlen = 1;

	msg.msg_control    = (caddr_t) &control_data;
	msg.msg_controllen = sizeof(control_data);
	msg.msg_flags      = 0;
	
	if (recvmsg(NUM2INT(socket_fd), &msg, 0) == -1) {
		rb_sys_fail("Cannot read file descriptor with recvmsg()");
		return Qnil;
	}
	
	control_header = CMSG_FIRSTHDR(&msg);
	if (control_header == NULL) {
		rb_raise(rb_eIOError, "No valid file descriptor received.");
		return Qnil;
	}
	if (control_header->cmsg_len   != EXPECTED_CMSG_LEN
	 || control_header->cmsg_level != SOL_SOCKET
	 || control_header->cmsg_type  != SCM_RIGHTS) {
		rb_raise(rb_eIOError, "No valid file descriptor received.");
		return Qnil;
	}
	#if defined(__APPLE__) || defined(__SOLARIS__) || defined(__arm__)
		return INT2NUM(control_data.fd);
	#else
		return INT2NUM(*((int *) CMSG_DATA(control_header)));
	#endif
}

.send_fd(socket_fd, fd_to_send) ⇒ Object

Send a file descriptor over the given Unix socket. You do not have to call this function directly. A convenience wrapper is provided by IO#send_io.

  • socket_fd (integer): The file descriptor of the socket.

  • fd_to_send (integer): The file descriptor to send.

  • Raises SystemCallError if something went wrong.



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# File 'ext/ruby/passenger_native_support.c', line 96

static VALUE
send_fd(VALUE self, VALUE socket_fd, VALUE fd_to_send) {
	struct msghdr msg;
	struct iovec vec;
	char dummy[1];
	#if defined(__APPLE__) || defined(__SOLARIS__) || defined(__arm__)
		struct {
			struct cmsghdr header;
			int fd;
		} control_data;
	#else
		char control_data[CMSG_SPACE(sizeof(int))];
	#endif
	struct cmsghdr *control_header;
	int control_payload;
	
	msg.msg_name = NULL;
	msg.msg_namelen = 0;
	
	/* Linux and Solaris require msg_iov to be non-NULL. */
	dummy[0]       = '\0';
	vec.iov_base   = dummy;
	vec.iov_len    = sizeof(dummy);
	msg.msg_iov    = &vec;
	msg.msg_iovlen = 1;
	
	msg.msg_control    = (caddr_t) &control_data;
	msg.msg_controllen = sizeof(control_data);
	msg.msg_flags      = 0;
	
	control_header = CMSG_FIRSTHDR(&msg);
	control_header->cmsg_level = SOL_SOCKET;
	control_header->cmsg_type  = SCM_RIGHTS;
	control_payload = NUM2INT(fd_to_send);
	#if defined(__APPLE__) || defined(__SOLARIS__) || defined(__arm__)
		control_header->cmsg_len = sizeof(control_data);
		control_data.fd = control_payload;
	#else
		control_header->cmsg_len = CMSG_LEN(sizeof(int));
		memcpy(CMSG_DATA(control_header), &control_payload, sizeof(int));
	#endif
	
	if (sendmsg(NUM2INT(socket_fd), &msg, 0) == -1) {
		rb_sys_fail("sendmsg(2)");
		return Qnil;
	}
	
	return Qnil;
}

.split_by_null_into_hash(data) ⇒ Object

Split the given string into an hash. Keys and values are obtained by splitting the string using the null character as the delimitor.



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# File 'ext/ruby/passenger_native_support.c', line 307

static VALUE
split_by_null_into_hash(VALUE self, VALUE data) {
	const char *cdata   = RSTRING_PTR(data);
	unsigned long len   = RSTRING_LEN(data);
	const char *begin   = cdata;
	const char *current = cdata;
	const char *end     = cdata + len;
	VALUE result, key, value;
	
	result = rb_hash_new();
	while (current < end) {
		if (*current == '\0') {
			key   = rb_str_substr(data, begin - cdata, current - begin);
			begin = current = current + 1;
			while (current < end) {
				if (*current == '\0') {
					value = rb_str_substr(data, begin - cdata, current - begin);;
					begin = current = current + 1;
					rb_hash_aset(result, key, value);
					break;
				} else {
					current++;
				}
			}
		} else {
			current++;
		}
	}
	return result;
}

.switch_user(username, uid, gid) ⇒ Object

Ruby’s implementations of initgroups, setgid and setuid are broken various ways, sigh… Ruby’s setgid and setuid can’t handle negative UIDs and initgroups is just broken. Work around it by using our own implementation.



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# File 'ext/ruby/passenger_native_support.c', line 592

static VALUE
switch_user(VALUE self, VALUE username, VALUE uid, VALUE gid) {
	uid_t the_uid = (uid_t) NUM2LL(uid);
	gid_t the_gid = (gid_t) NUM2LL(gid);
	
	if (initgroups(RSTRING_PTR(username), the_gid) == -1) {
		rb_sys_fail("initgroups");
	}
	if (setgid(the_gid) == -1) {
		rb_sys_fail("setgid");
	}
	if (setuid(the_uid) == -1) {
		rb_sys_fail("setuid");
	}
	return Qnil;
}

.writev(fd, components) ⇒ Object

Writes all of the strings in the components array into the given file descriptor using the writev() system call. Unlike IO#write, this method does not require one to concatenate all those strings into a single buffer in order to send the data in a single system call. Thus, #writev is a great way to perform zero-copy I/O.

Unlike the raw writev() system call, this method ensures that all given data is written before returning, by performing multiple writev() calls and whatever else is necessary.

writev(@socket.fileno, ["hello ", "world", "\n"])



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# File 'ext/ruby/passenger_native_support.c', line 556

static VALUE
f_writev(VALUE self, VALUE fd, VALUE components) {
	return f_generic_writev(fd, &components, 1);
}

.writev2(fd, components1, components2) ⇒ Object

Like #writev, but accepts two arrays. The data is written in the given order.

writev2(@socket.fileno, ["hello ", "world", "\n"], ["another ", "message\n"])



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# File 'ext/ruby/passenger_native_support.c', line 566

static VALUE
f_writev2(VALUE self, VALUE fd, VALUE components1, VALUE components2) {
	VALUE array_of_components[2] = { components1, components2 };
	return f_generic_writev(fd, array_of_components, 2);
}

.writev3(fd, components1, components2, components3) ⇒ Object

Like #writev, but accepts three arrays. The data is written in the given order.

writev3(@socket.fileno,
  ["hello ", "world", "\n"],
  ["another ", "message\n"],
  ["yet ", "another ", "one", "\n"])



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# File 'ext/ruby/passenger_native_support.c', line 580

static VALUE
f_writev3(VALUE self, VALUE fd, VALUE components1, VALUE components2, VALUE components3) {
	VALUE array_of_components[3] = { components1, components2, components3 };
	return f_generic_writev(fd, array_of_components, 3);
}