mercurial/hook.py
author C. Masloch <pushbx@ulukai.org>
Wed, 20 Apr 2022 19:24:39 +0200
changeset 49449 cfff73cab721
parent 48913 f254fc73d956
child 50325 2761ce777fc4
permissions -rw-r--r--
rebase: add boolean config item rebase.store-source This allows to use rebase without recording a rebase_source extra field. This is useful for example to build a mirror converted from another SCM (such as svn) by converting only new revisions, and then incrementally add them to the destination by pulling from the newly converted (unrelated) repo and rebasing the new revisions onto the last old already stored changeset. Without this patch the rebased changesets would always receive some rebase_source that would depend on the particular history of the conversion process, instead of only depending on the original source revisions. This is used to implement a hg mirror repo of SvarDOS (a partially nonfree but completely redistributable DOS distribution) in the scripts at https://hg.pushbx.org/ecm/svardos.scr/ In particular, cre.sh creates an svn mirror, upd.sh recreates an entire hg repo from the svn mirror (which takes too long to do in a regular job), and akt.sh uses hg convert with the config item convert.svn.startrev to incrementally convert only the two most recent revisions already found in the mirror destination plus any possible new revisions. If any are found, the temporary repo's changesets are pulled into the destination (as changesets from an unrelated repository). Then the changesets corresponding to the new revisions are rebased onto the prior final changeset. (Finally, the two remaining duplicates of the prior head and its parent are stripped from the destination repository.) Without this patch, the particular rebase_source extra field would depend on the order and times at which akt.sh was used, instead of only depending on the source repository. In other words, whatever sequence of upd.sh and akt.sh is used at whatever times, it is desired that the final output repositories always match each other exactly.

# hook.py - hook support for mercurial
#
# Copyright 2007 Olivia Mackall <olivia@selenic.com>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.


import contextlib
import errno
import os
import sys

from .i18n import _
from .pycompat import getattr
from . import (
    demandimport,
    encoding,
    error,
    extensions,
    pycompat,
    util,
)
from .utils import (
    procutil,
    resourceutil,
    stringutil,
)


def pythonhook(ui, repo, htype, hname, funcname, args, throw):
    """call python hook. hook is callable object, looked up as
    name in python module. if callable returns "true", hook
    fails, else passes. if hook raises exception, treated as
    hook failure. exception propagates if throw is "true".

    reason for "true" meaning "hook failed" is so that
    unmodified commands (e.g. mercurial.commands.update) can
    be run as hooks without wrappers to convert return values."""

    if callable(funcname):
        obj = funcname
        funcname = pycompat.sysbytes(obj.__module__ + "." + obj.__name__)
    else:
        d = funcname.rfind(b'.')
        if d == -1:
            raise error.HookLoadError(
                _(b'%s hook is invalid: "%s" not in a module')
                % (hname, funcname)
            )
        modname = funcname[:d]
        oldpaths = sys.path
        if resourceutil.mainfrozen():
            # binary installs require sys.path manipulation
            modpath, modfile = os.path.split(modname)
            if modpath and modfile:
                sys.path = sys.path[:] + [modpath]
                modname = modfile
        with demandimport.deactivated():
            try:
                obj = __import__(pycompat.sysstr(modname))
            except (ImportError, SyntaxError):
                e1 = sys.exc_info()
                try:
                    # extensions are loaded with hgext_ prefix
                    obj = __import__("hgext_%s" % pycompat.sysstr(modname))
                except (ImportError, SyntaxError):
                    e2 = sys.exc_info()
                    if ui.tracebackflag:
                        ui.warn(
                            _(
                                b'exception from first failed import '
                                b'attempt:\n'
                            )
                        )
                    ui.traceback(e1)
                    if ui.tracebackflag:
                        ui.warn(
                            _(
                                b'exception from second failed import '
                                b'attempt:\n'
                            )
                        )
                    ui.traceback(e2)

                    if not ui.tracebackflag:
                        tracebackhint = _(
                            b'run with --traceback for stack trace'
                        )
                    else:
                        tracebackhint = None
                    raise error.HookLoadError(
                        _(b'%s hook is invalid: import of "%s" failed')
                        % (hname, modname),
                        hint=tracebackhint,
                    )
        sys.path = oldpaths
        try:
            for p in funcname.split(b'.')[1:]:
                obj = getattr(obj, p)
        except AttributeError:
            raise error.HookLoadError(
                _(b'%s hook is invalid: "%s" is not defined')
                % (hname, funcname)
            )
        if not callable(obj):
            raise error.HookLoadError(
                _(b'%s hook is invalid: "%s" is not callable')
                % (hname, funcname)
            )

    ui.note(_(b"calling hook %s: %s\n") % (hname, funcname))
    starttime = util.timer()

    try:
        r = obj(ui=ui, repo=repo, hooktype=htype, **pycompat.strkwargs(args))
    except Exception as exc:
        if isinstance(exc, error.Abort):
            ui.warn(_(b'error: %s hook failed: %s\n') % (hname, exc.args[0]))
        else:
            ui.warn(
                _(b'error: %s hook raised an exception: %s\n')
                % (hname, stringutil.forcebytestr(exc))
            )
        if throw:
            raise
        if not ui.tracebackflag:
            ui.warn(_(b'(run with --traceback for stack trace)\n'))
        ui.traceback()
        return True, True
    finally:
        duration = util.timer() - starttime
        ui.log(
            b'pythonhook',
            b'pythonhook-%s: %s finished in %0.2f seconds\n',
            htype,
            funcname,
            duration,
        )
    if r:
        if throw:
            raise error.HookAbort(_(b'%s hook failed') % hname)
        ui.warn(_(b'warning: %s hook failed\n') % hname)
    return r, False


def _exthook(ui, repo, htype, name, cmd, args, throw):
    starttime = util.timer()
    env = {}

    # make in-memory changes visible to external process
    if repo is not None:
        tr = repo.currenttransaction()
        repo.dirstate.write(tr)
        if tr and tr.writepending():
            env[b'HG_PENDING'] = repo.root
    env[b'HG_HOOKTYPE'] = htype
    env[b'HG_HOOKNAME'] = name

    if ui.config(b'hooks', b'%s:run-with-plain' % name) == b'auto':
        plain = ui.plain()
    else:
        plain = ui.configbool(b'hooks', b'%s:run-with-plain' % name)
    if plain:
        env[b'HGPLAIN'] = b'1'
    else:
        env[b'HGPLAIN'] = b''

    for k, v in args.items():
        # transaction changes can accumulate MBs of data, so skip it
        # for external hooks
        if k == b'changes':
            continue
        if callable(v):
            v = v()
        if isinstance(v, (dict, list)):
            v = stringutil.pprint(v)
        env[b'HG_' + k.upper()] = v

    if ui.configbool(b'hooks', b'tonative.%s' % name, False):
        oldcmd = cmd
        cmd = procutil.shelltonative(cmd, env)
        if cmd != oldcmd:
            ui.note(_(b'converting hook "%s" to native\n') % name)

    ui.note(_(b"running hook %s: %s\n") % (name, cmd))

    if repo:
        cwd = repo.root
    else:
        cwd = encoding.getcwd()
    r = ui.system(cmd, environ=env, cwd=cwd, blockedtag=b'exthook-%s' % (name,))

    duration = util.timer() - starttime
    ui.log(
        b'exthook',
        b'exthook-%s: %s finished in %0.2f seconds\n',
        name,
        cmd,
        duration,
    )
    if r:
        desc = procutil.explainexit(r)
        if throw:
            raise error.HookAbort(_(b'%s hook %s') % (name, desc))
        ui.warn(_(b'warning: %s hook %s\n') % (name, desc))
    return r


# represent an untrusted hook command
_fromuntrusted = object()


def _allhooks(ui):
    """return a list of (hook-id, cmd) pairs sorted by priority"""
    hooks = _hookitems(ui)
    # Be careful in this section, propagating the real commands from untrusted
    # sources would create a security vulnerability, make sure anything altered
    # in that section uses "_fromuntrusted" as its command.
    untrustedhooks = _hookitems(ui, _untrusted=True)
    for name, value in untrustedhooks.items():
        trustedvalue = hooks.get(name, ((), (), name, _fromuntrusted))
        if value != trustedvalue:
            (lp, lo, lk, lv) = trustedvalue
            hooks[name] = (lp, lo, lk, _fromuntrusted)
    # (end of the security sensitive section)
    return [(k, v) for p, o, k, v in sorted(hooks.values())]


def _hookitems(ui, _untrusted=False):
    """return all hooks items ready to be sorted"""
    hooks = {}
    for name, cmd in ui.configitems(b'hooks', untrusted=_untrusted):
        if (
            name.startswith(b'priority.')
            or name.startswith(b'tonative.')
            or b':' in name
        ):
            continue

        priority = ui.configint(b'hooks', b'priority.%s' % name, 0)
        hooks[name] = ((-priority,), (len(hooks),), name, cmd)
    return hooks


_redirect = False


def redirect(state):
    global _redirect
    _redirect = state


def hashook(ui, htype):
    """return True if a hook is configured for 'htype'"""
    if not ui.callhooks:
        return False
    for hname, cmd in _allhooks(ui):
        if hname.split(b'.')[0] == htype and cmd:
            return True
    return False


def hook(ui, repo, htype, throw=False, **args):
    if not ui.callhooks:
        return False

    hooks = []
    for hname, cmd in _allhooks(ui):
        if hname.split(b'.')[0] == htype and cmd:
            hooks.append((hname, cmd))

    res = runhooks(ui, repo, htype, hooks, throw=throw, **args)
    r = False
    for hname, cmd in hooks:
        r = res[hname][0] or r
    return r


@contextlib.contextmanager
def redirect_stdio():
    """Redirects stdout to stderr, if possible."""

    oldstdout = -1
    try:
        if _redirect:
            try:
                stdoutno = procutil.stdout.fileno()
                stderrno = procutil.stderr.fileno()
                # temporarily redirect stdout to stderr, if possible
                if stdoutno >= 0 and stderrno >= 0:
                    procutil.stdout.flush()
                    oldstdout = os.dup(stdoutno)
                    os.dup2(stderrno, stdoutno)
            except (OSError, AttributeError):
                # files seem to be bogus, give up on redirecting (WSGI, etc)
                pass

        yield

    finally:
        # The stderr is fully buffered on Windows when connected to a pipe.
        # A forcible flush is required to make small stderr data in the
        # remote side available to the client immediately.
        try:
            procutil.stderr.flush()
        except IOError as err:
            if err.errno not in (errno.EPIPE, errno.EIO, errno.EBADF):
                raise error.StdioError(err)

        if _redirect and oldstdout >= 0:
            try:
                procutil.stdout.flush()  # write hook output to stderr fd
            except IOError as err:
                if err.errno not in (errno.EPIPE, errno.EIO, errno.EBADF):
                    raise error.StdioError(err)
            os.dup2(oldstdout, stdoutno)
            os.close(oldstdout)


def runhooks(ui, repo, htype, hooks, throw=False, **args):
    args = pycompat.byteskwargs(args)
    res = {}

    with redirect_stdio():
        for hname, cmd in hooks:
            if cmd is _fromuntrusted:
                if throw:
                    raise error.HookAbort(
                        _(b'untrusted hook %s not executed') % hname,
                        hint=_(b"see 'hg help config.trusted'"),
                    )
                ui.warn(_(b'warning: untrusted hook %s not executed\n') % hname)
                r = 1
                raised = False
            elif callable(cmd):
                r, raised = pythonhook(ui, repo, htype, hname, cmd, args, throw)
            elif cmd.startswith(b'python:'):
                if cmd.count(b':') >= 2:
                    path, cmd = cmd[7:].rsplit(b':', 1)
                    path = util.expandpath(path)
                    if repo:
                        path = os.path.join(repo.root, path)
                    try:
                        mod = extensions.loadpath(path, b'hghook.%s' % hname)
                    except Exception:
                        ui.write(_(b"loading %s hook failed:\n") % hname)
                        raise
                    hookfn = getattr(mod, cmd)
                else:
                    hookfn = cmd[7:].strip()
                r, raised = pythonhook(
                    ui, repo, htype, hname, hookfn, args, throw
                )
            else:
                r = _exthook(ui, repo, htype, hname, cmd, args, throw)
                raised = False

            res[hname] = r, raised

    return res