tests/testlib/sigpipe-remote.py

tests: fix glob pattern for dynamic timer alignment

The number of space characters varies depending on the number of digits of the
timer, making some tests fail on slow machines in an unintended way:

```diff
--- /build/mercurial-6.1/tests/test-merge-halt.t
+++ /build/mercurial-6.1/tests/test-merge-halt.t.err
@@ -210,6 +210,6 @@
   merge halted after failed merge (see hg resolve)
   [240]
   $ hg shelve --list
-  default         (* ago)    changes to: foo (glob)
+  default         (11s ago)   changes to: foo
   $ hg unshelve --abort
   unshelve of 'default' aborted
ERROR: test-merge-halt.t output changed
```

Differential Revision: https://phab.mercurial-scm.org/D12381

#!/usr/bin/env python3

import io
import os
import subprocess
import sys
import time


if isinstance(sys.stdout.buffer, io.BufferedWriter):
    print('SIGPIPE-HELPER: script need unbuffered output', file=sys.stderr)
    sys.exit(255)

DEBUG_FILE = os.environ.get('SIGPIPE_REMOTE_DEBUG_FILE')
if DEBUG_FILE is None:
    debug_stream = sys.stderr.buffer
else:
    debug_stream = open(DEBUG_FILE, 'bw', buffering=0)

SYNCFILE1 = os.environ.get('SYNCFILE1')
SYNCFILE2 = os.environ.get('SYNCFILE2')
if SYNCFILE1 is None:
    print('SIGPIPE-HELPER: missing variable $SYNCFILE1', file=sys.stderr)
    sys.exit(255)
if SYNCFILE2 is None:
    print('SIGPIPE-HELPER: missing variable $SYNCFILE2', file=sys.stderr)
    sys.exit(255)


def _timeout_factor():
    """return the current modification to timeout"""
    default = int(os.environ.get('HGTEST_TIMEOUT_DEFAULT', 360))
    current = int(os.environ.get('HGTEST_TIMEOUT', default))
    if current == 0:
        return 1
    return current / float(default)


def wait_file(path, timeout=10):
    timeout *= _timeout_factor()
    start = time.time()
    while not os.path.exists(path):
        if (time.time() - start) > timeout:
            raise RuntimeError(b"timed out waiting for file: %s" % path)
        time.sleep(0.01)


def write_file(path, content=b''):
    with open(path, 'wb') as f:
        f.write(content)


# end of mercurial.testing content


def sysbytes(s):
    return s.encode('utf-8')


def sysstr(s):
    return s.decode('latin-1')


debug_stream.write(b'SIGPIPE-HELPER: Starting\n')

TESTLIB_DIR = os.path.dirname(sys.argv[0])
WAIT_SCRIPT = os.path.join(TESTLIB_DIR, 'wait-on-file')

hooks_cmd = '%s 10 %s %s'
hooks_cmd %= (
    WAIT_SCRIPT,
    SYNCFILE2,
    SYNCFILE1,
)

try:
    cmd = ['hg']
    cmd += sys.argv[1:]
    sub = subprocess.Popen(
        cmd,
        bufsize=0,
        close_fds=True,
        stdin=sys.stdin,
        stdout=subprocess.PIPE,
        stderr=subprocess.PIPE,
    )

    basedir = os.path.dirname(sys.argv[0])
    worker = os.path.join(basedir, 'sigpipe-worker.py')

    cmd = [sys.executable, worker]

    stdout_worker = subprocess.Popen(
        cmd,
        bufsize=0,
        close_fds=True,
        stdin=sub.stdout,
        stdout=sys.stdout,
        stderr=sys.stderr,
    )

    stderr_worker = subprocess.Popen(
        cmd,
        bufsize=0,
        close_fds=True,
        stdin=sub.stderr,
        stdout=sys.stderr,
        stderr=sys.stderr,
    )
    debug_stream.write(b'SIGPIPE-HELPER: Redirection in place\n')
    os.close(sub.stdout.fileno())
    os.close(sub.stderr.fileno())
    debug_stream.write(b'SIGPIPE-HELPER: pipes closed in main\n')

    try:
        wait_file(sysbytes(SYNCFILE1))
    except RuntimeError as exc:
        msg = sysbytes(str(exc))
        debug_stream.write(b'SIGPIPE-HELPER: wait failed: %s\n' % msg)
    else:
        debug_stream.write(b'SIGPIPE-HELPER: SYNCFILE1 detected\n')
    stdout_worker.kill()
    stderr_worker.kill()
    stdout_worker.wait(10)
    stderr_worker.wait(10)
    debug_stream.write(b'SIGPIPE-HELPER: worker killed\n')

    debug_stream.write(b'SIGPIPE-HELPER: creating SYNCFILE2\n')
    write_file(sysbytes(SYNCFILE2))
finally:
    debug_stream.write(b'SIGPIPE-HELPER: Shutting down\n')
    if not sys.stdin.closed:
        sys.stdin.close()
    try:
        sub.wait(timeout=30)
    except subprocess.TimeoutExpired:
        msg = b'SIGPIPE-HELPER: Server process failed to terminate\n'
        debug_stream.write(msg)
        sub.kill()
        sub.wait()
        msg = b'SIGPIPE-HELPER: Server process killed\n'
    else:
        msg = b'SIGPIPE-HELPER: Server process terminated with status %d\n'
        msg %= sub.returncode
        debug_stream.write(msg)
    debug_stream.write(b'SIGPIPE-HELPER: Shut down\n')