view tests/f @ 49522:52464a20add0

rhg: parallellize computation of [unsure_is_modified]

[unsure_is_modified] is called for every file for which we can't
determine its status based on its size and mtime alone.

In particular, this happens if the mtime of the file changes
without its contents changing.

Parallellizing this improves performance significantly when
we have many of these files.

Here's an example run (on a repo with ~400k files after dropping FS caches)

```
before:
real	0m53.901s
user	0m27.806s
sys	0m31.325s

after:
real	0m32.017s
user	0m34.277s
sys	1m26.250s
```

Another example run (a different FS):

```
before:
real	3m28.479s
user	0m31.800s
sys	0m25.324s

after:
real	0m29.751s
user	0m41.814s
sys	1m15.387s
```

#!/usr/bin/env python3

"""
Utility for inspecting files in various ways.

This tool is like the collection of tools found in a unix environment but are
cross platform and stable and suitable for our needs in the test suite.

This can be used instead of tools like:
  [
  dd
  find
  head
  hexdump
  ls
  md5sum
  readlink
  sha1sum
  stat
  tail
  test
  readlink.py
  md5sum.py
"""


import binascii
import glob
import hashlib
import optparse
import os
import re
import sys

# Python 3 adapters
ispy3 = sys.version_info[0] >= 3
if ispy3:

    def iterbytes(s):
        for i in range(len(s)):
            yield s[i : i + 1]


else:
    iterbytes = iter


def visit(opts, filenames, outfile):
    """Process filenames in the way specified in opts, writing output to
    outfile."""
    for f in sorted(filenames):
        isstdin = f == '-'
        if not isstdin and not os.path.lexists(f):
            outfile.write(b'%s: file not found\n' % f.encode('utf-8'))
            continue
        quiet = opts.quiet and not opts.recurse or isstdin
        isdir = os.path.isdir(f)
        islink = os.path.islink(f)
        isfile = os.path.isfile(f) and not islink
        dirfiles = None
        content = None
        facts = []
        if isfile:
            if opts.type:
                facts.append(b'file')
            if any((opts.hexdump, opts.dump, opts.md5, opts.sha1, opts.sha256)):
                with open(f, 'rb') as fobj:
                    content = fobj.read()
        elif islink:
            if opts.type:
                facts.append(b'link')
            content = os.readlink(f).encode('utf8')
        elif isstdin:
            content = getattr(sys.stdin, 'buffer', sys.stdin).read()
            if opts.size:
                facts.append(b'size=%d' % len(content))
        elif isdir:
            if opts.recurse or opts.type:
                dirfiles = glob.glob(f + '/*')
                facts.append(b'directory with %d files' % len(dirfiles))
        elif opts.type:
            facts.append(b'type unknown')
        if not isstdin:
            stat = os.lstat(f)
            if opts.size and not isdir:
                facts.append(b'size=%d' % stat.st_size)
            if opts.mode and not islink:
                facts.append(b'mode=%o' % (stat.st_mode & 0o777))
            if opts.links:
                facts.append(b'links=%d' % stat.st_nlink)
            if opts.newer:
                # mtime might be in whole seconds so newer file might be same
                if stat.st_mtime >= os.stat(opts.newer).st_mtime:
                    facts.append(
                        b'newer than %s' % opts.newer.encode('utf8', 'replace')
                    )
                else:
                    facts.append(
                        b'older than %s' % opts.newer.encode('utf8', 'replace')
                    )
        if opts.md5 and content is not None:
            h = hashlib.md5(content)
            facts.append(b'md5=%s' % binascii.hexlify(h.digest())[: opts.bytes])
        if opts.sha1 and content is not None:
            h = hashlib.sha1(content)
            facts.append(
                b'sha1=%s' % binascii.hexlify(h.digest())[: opts.bytes]
            )
        if opts.sha256 and content is not None:
            h = hashlib.sha256(content)
            facts.append(
                b'sha256=%s' % binascii.hexlify(h.digest())[: opts.bytes]
            )
        if isstdin:
            outfile.write(b', '.join(facts) + b'\n')
        elif facts:
            outfile.write(b'%s: %s\n' % (f.encode('utf-8'), b', '.join(facts)))
        elif not quiet:
            outfile.write(b'%s:\n' % f.encode('utf-8'))
        if content is not None:
            chunk = content
            if not islink:
                if opts.lines:
                    if opts.lines >= 0:
                        chunk = b''.join(chunk.splitlines(True)[: opts.lines])
                    else:
                        chunk = b''.join(chunk.splitlines(True)[opts.lines :])
                if opts.bytes:
                    if opts.bytes >= 0:
                        chunk = chunk[: opts.bytes]
                    else:
                        chunk = chunk[opts.bytes :]
            if opts.hexdump:
                for i in range(0, len(chunk), 16):
                    s = chunk[i : i + 16]
                    outfile.write(
                        b'%04x: %-47s |%s|\n'
                        % (
                            i,
                            b' '.join(b'%02x' % ord(c) for c in iterbytes(s)),
                            re.sub(b'[^ -~]', b'.', s),
                        )
                    )
            if opts.dump:
                if not quiet:
                    outfile.write(b'>>>\n')
                outfile.write(chunk)
                if not quiet:
                    if chunk.endswith(b'\n'):
                        outfile.write(b'<<<\n')
                    else:
                        outfile.write(b'\n<<< no trailing newline\n')
        if opts.recurse and dirfiles:
            assert not isstdin
            visit(opts, dirfiles, outfile)


if __name__ == "__main__":
    parser = optparse.OptionParser("%prog [options] [filenames]")
    parser.add_option(
        "-t",
        "--type",
        action="store_true",
        help="show file type (file or directory)",
    )
    parser.add_option(
        "-m", "--mode", action="store_true", help="show file mode"
    )
    parser.add_option(
        "-l", "--links", action="store_true", help="show number of links"
    )
    parser.add_option(
        "-s", "--size", action="store_true", help="show size of file"
    )
    parser.add_option(
        "-n", "--newer", action="store", help="check if file is newer (or same)"
    )
    parser.add_option(
        "-r", "--recurse", action="store_true", help="recurse into directories"
    )
    parser.add_option(
        "-S",
        "--sha1",
        action="store_true",
        help="show sha1 hash of the content",
    )
    parser.add_option(
        "",
        "--sha256",
        action="store_true",
        help="show sha256 hash of the content",
    )
    parser.add_option(
        "-M", "--md5", action="store_true", help="show md5 hash of the content"
    )
    parser.add_option(
        "-D", "--dump", action="store_true", help="dump file content"
    )
    parser.add_option(
        "-H", "--hexdump", action="store_true", help="hexdump file content"
    )
    parser.add_option(
        "-B", "--bytes", type="int", help="number of characters to dump"
    )
    parser.add_option(
        "-L", "--lines", type="int", help="number of lines to dump"
    )
    parser.add_option(
        "-q", "--quiet", action="store_true", help="no default output"
    )
    (opts, filenames) = parser.parse_args(sys.argv[1:])
    if not filenames:
        filenames = ['-']

    visit(opts, filenames, getattr(sys.stdout, 'buffer', sys.stdout))