Migrate STDIN/STDOUT/STDERR handles from PHP resources to FDs

[fredemmott]

Non-CLI handles are still using PHP resources, as the replacements are not yet available in FB builds of HHVM.

Test Plan:

use namespace HH\Lib\IO;

<<__EntryPoint>>
async function main(): Awaitable<void> {
  require_once('vendor/autoload.hack');
  \Facebook\AutoloadMap\initialize();

  $in = IO\request_input();
  $out = IO\request_output();
  $err = IO\request_error();

  var_dump($in, $out, $err);

  printf("Read from in: '%s'\n", await $in->readAsync(1024));
  print("Writing to out\n");
  $out->write("Hello,\n");
  print("Writing to error\n");
  $err?->write("world.\n");
}

Standalone CLI

$ echo herpderp | hhvm test.hack
object(HH\Lib\_Private\_IO\StdioReadHandle) (2) {
  ["isAwaitable":protected]=>
  bool(true)
  ["impl":protected]=>
  object(HH\Lib\OS\FileDescriptor) (2) {
    ["type"]=>
    string(8) "resource"
    ["fd"]=>
    int(0)
  }
}
object(HH\Lib\_Private\_IO\StdioWriteHandle) (2) {
  ["isAwaitable":protected]=>
  bool(true)
  ["impl":protected]=>
  object(HH\Lib\OS\FileDescriptor) (2) {
    ["type"]=>
    string(8) "resource"
    ["fd"]=>
    int(1)
  }
}
object(HH\Lib\_Private\_IO\StdioWriteHandle) (2) {
  ["isAwaitable":protected]=>
  bool(true)
  ["impl":protected]=>
  object(HH\Lib\OS\FileDescriptor) (2) {
    ["type"]=>
    string(8) "resource"
    ["fd"]=>
    int(2)
  }
}
Read from in: 'herpderp
'
Writing to out
Hello,
Writing to error
world.

• FDs are 0, 1, 2, as expected
• stdin is read, with newline
• stdout and stderr are written

STDOUT vs STDERR

$ echo herpderp | hhvm test.hack 2>/dev/null
object(HH\Lib\_Private\_IO\StdioReadHandle) (2) {
  ["isAwaitable":protected]=>
  bool(true)
  ["impl":protected]=>
  object(HH\Lib\OS\FileDescriptor) (2) {
    ["type"]=>
    string(8) "resource"
    ["fd"]=>
    int(0)
  }
}
object(HH\Lib\_Private\_IO\StdioWriteHandle) (2) {
  ["isAwaitable":protected]=>
  bool(true)
  ["impl":protected]=>
  object(HH\Lib\OS\FileDescriptor) (2) {
    ["type"]=>
    string(8) "resource"
    ["fd"]=>
    int(1)
  }
}
object(HH\Lib\_Private\_IO\StdioWriteHandle) (2) {
  ["isAwaitable":protected]=>
  bool(true)
  ["impl":protected]=>
  object(HH\Lib\OS\FileDescriptor) (2) {
    ["type"]=>
    string(8) "resource"
    ["fd"]=>
    int(2)
  }
}
Read from in: 'herpderp
'
Writing to out
Hello,
Writing to error

• no change to stdout stuff
• stderr output is not shown (redirected to /dev/null on command line)

CLI Server

$ echo herpderp | hhvm -d hhvm.unix_server_path=/tmp/hhvm.sock -d hhvm.use_remote_unix_server=true test.hack
object(HH\Lib\_Private\_IO\StdioReadHandle) (2) {
  ["isAwaitable":protected]=>
  bool(true)
  ["impl":protected]=>
  object(HH\Lib\OS\FileDescriptor) (2) {
    ["type"]=>
    string(8) "resource"
    ["fd"]=>
    int(29)
  }
}
object(HH\Lib\_Private\_IO\StdioWriteHandle) (2) {
  ["isAwaitable":protected]=>
  bool(true)
  ["impl":protected]=>
  object(HH\Lib\OS\FileDescriptor) (2) {
    ["type"]=>
    string(8) "resource"
    ["fd"]=>
    int(30)
  }
}
object(HH\Lib\_Private\_IO\StdioWriteHandle) (2) {
  ["isAwaitable":protected]=>
  bool(true)
  ["impl":protected]=>
  object(HH\Lib\OS\FileDescriptor) (2) {
    ["type"]=>
    string(8) "resource"
    ["fd"]=>
    int(31)
  }
}
Read from in: 'herpderp
'
Writing to out
Hello,
Writing to error
world.
$ echo herpderp | hhvm -d hhvm.unix_server_path=/tmp/hhvm.sock -d hhvm.use_remote_unix_server=true test.hack 2>/dev/null
object(HH\Lib\_Private\_IO\StdioReadHandle) (2) {
  ["isAwaitable":protected]=>
  bool(true)
  ["impl":protected]=>
  object(HH\Lib\OS\FileDescriptor) (2) {
    ["type"]=>
    string(8) "resource"
    ["fd"]=>
    int(29)
  }
}
object(HH\Lib\_Private\_IO\StdioWriteHandle) (2) {
  ["isAwaitable":protected]=>
  bool(true)
  ["impl":protected]=>
  object(HH\Lib\OS\FileDescriptor) (2) {
    ["type"]=>
    string(8) "resource"
    ["fd"]=>
    int(30)
  }
}
object(HH\Lib\_Private\_IO\StdioWriteHandle) (2) {
  ["isAwaitable":protected]=>
  bool(true)
  ["impl":protected]=>
  object(HH\Lib\OS\FileDescriptor) (2) {
    ["type"]=>
    string(8) "resource"
    ["fd"]=>
    int(31)
  }
}
Read from in: 'herpderp
'
Writing to out
Hello,
Writing to error

• OS\FileDescriptor objects are still used
• they wrap the PHP resources, as expected, but a raw FD is extracted from them
• the FDs are sequential
• they work the same as for standalone CLI mode, including STDERR redirection

HTTP Server

$ curl http://localhost:8080/test.hack
object(HH\Lib\_Private\_IO\RequestReadHandle) (2) {
  ["isAwaitable":protected]=>
  bool(true)
  ["impl":protected]=>
  resource(4) of type (stream)
}
object(HH\Lib\_Private\_IO\ResponseWriteHandle) (2) {
  ["isAwaitable":protected]=>
  bool(true)
  ["impl":protected]=>
  resource(5) of type (stream)
}
NULL
Read from in: ''
Writing to out
Hello,
Writing to error

• input/output do not have a FileDescriptor - pure PHP resources.
• error is null (expected)
• no error output, nullsafe call
• input is empty, GET request

Request Input

$ curl -d herpderp http://localhost:8080/test.hack
object(HH\Lib\_Private\_IO\RequestReadHandle) (2) {
  ["isAwaitable":protected]=>
  bool(true)
  ["impl":protected]=>
  resource(4) of type (stream)
}
object(HH\Lib\_Private\_IO\ResponseWriteHandle) (2) {
  ["isAwaitable":protected]=>
  bool(true)
  ["impl":protected]=>
  resource(5) of type (stream)
}
NULL
Read from in: 'herpderp'
Writing to out
Hello,
Writing to error

• POST data is available from request_input()
• Other output as above

[facebook-github-bot]

@fredemmott merged this pull request in hhvm/hsl-experimental@0a1493cc4a4cb18ef9efd4fcbab2bb0d8d5dcadc.