contrib/buildrpm

util: add a file object proxy that can notify observers

There are various places in Mercurial where we may want to
instrument low-level I/O. The use cases I can think of all
involve development-type activities like monitoring the raw
bytes passing through a file (for testing and debugging),
counting the number of I/O function calls (for performance
monitoring), and changing the behavior of I/O function calls
(e.g. simulating a failure) (to facilitate testing).

This commit invents a mechanism to wrap a file object so we
can observe activity on it. We have similar functionality in
badserverext.py. But that's a test-only extension and is pretty
specific to the HTTP server. I would like a mechanism in core
that is sufficiently generic so it can be used by multiple
consumers, including `hg debug*` commands.

The added code consists of a proxy type for file objects.
It is bound to an "observer," which receives callbacks whenever
I/O methods are called.

We also add an implementation of an observer that logs specific
I/O events. This observer will be used in an upcoming commit
to record low-level wire protocol activity.

A helper function to convert a file object into an observed
file object has also been implemented.

I don't anticipate any critical functionality in core using
these types. So I don't think explicit test coverage is
worth implementing.

Differential Revision: https://phab.mercurial-scm.org/D2462

#!/bin/bash -e
#
# Build a Mercurial RPM from the current repo
#
# Tested on
# - Fedora 20
# - CentOS 5
# - centOS 6

. $(dirname $0)/packagelib.sh

BUILD=1
RPMBUILDDIR="$PWD/rpmbuild"

while [ "$1" ]; do
    case "$1" in
    --prepare )
        shift
        BUILD=
        ;;
    --withpython | --with-python)
        shift
        PYTHONVER=2.7.14
        PYTHONMD5=cee2e4b33ad3750da77b2e85f2f8b724
        ;;
    --rpmbuilddir )
        shift
        RPMBUILDDIR="$1"
        shift
        ;;
    * )
        echo "Invalid parameter $1!" 1>&2
        exit 1
        ;;
    esac
done

cd "`dirname $0`/.."

specfile=$PWD/contrib/mercurial.spec
if [ ! -f $specfile ]; then
    echo "Cannot find $specfile!" 1>&2
    exit 1
fi

if [ ! -d .hg ]; then
    echo 'You are not inside a Mercurial repository!' 1>&2
    exit 1
fi

gethgversion

# TODO: handle distance/node set, and type set

if [ -z "$type" ] ; then
   release=1
else
    release=0.9_$type
fi

if [ -n "$distance" ] ; then
    release=$release+$distance_$node
fi

if [ "$PYTHONVER" ]; then
    release=$release+$PYTHONVER
    RPMPYTHONVER=$PYTHONVER
else
    RPMPYTHONVER=%{nil}
fi

mkdir -p $RPMBUILDDIR/{SOURCES,BUILD,SRPMS,RPMS}
$HG archive -t tgz $RPMBUILDDIR/SOURCES/mercurial-$version-$release.tar.gz
if [ "$PYTHONVER" ]; then
(
    mkdir -p build
    cd build
    PYTHON_SRCFILE=Python-$PYTHONVER.tgz
    [ -f $PYTHON_SRCFILE ] || curl -Lo $PYTHON_SRCFILE http://www.python.org/ftp/python/$PYTHONVER/$PYTHON_SRCFILE
    if [ "$PYTHONMD5" ]; then
        echo "$PYTHONMD5 $PYTHON_SRCFILE" | md5sum -w -c
    fi
    ln -f $PYTHON_SRCFILE $RPMBUILDDIR/SOURCES/$PYTHON_SRCFILE

    DOCUTILSVER=`sed -ne "s/^%global docutilsname docutils-//p" $specfile`
    DOCUTILS_SRCFILE=docutils-$DOCUTILSVER.tar.gz
    [ -f $DOCUTILS_SRCFILE ] || curl -Lo $DOCUTILS_SRCFILE http://downloads.sourceforge.net/project/docutils/docutils/$DOCUTILSVER/$DOCUTILS_SRCFILE
    DOCUTILSMD5=`sed -ne "s/^%global docutilsmd5 //p" $specfile`
    if [ "$DOCUTILSMD5" ]; then
        echo "$DOCUTILSMD5 $DOCUTILS_SRCFILE" | md5sum -w -c
    fi
    ln -f $DOCUTILS_SRCFILE $RPMBUILDDIR/SOURCES/$DOCUTILS_SRCFILE
)
fi

mkdir -p $RPMBUILDDIR/SPECS
rpmspec=$RPMBUILDDIR/SPECS/mercurial.spec

sed -e "s,^Version:.*,Version: $version," \
    -e "s,^Release:.*,Release: $release," \
    $specfile > $rpmspec

echo >> $rpmspec
echo "%changelog" >> $rpmspec

if echo $version | grep '+' > /dev/null 2>&1; then
    latesttag="`echo $version | sed -e 's/+.*//'`"
    $HG log -r .:"$latesttag" -fM \
        --template '{date|hgdate}\t{author}\t{desc|firstline}\n' | python -c '
import sys, time

def datestr(date, format):
    return time.strftime(format, time.gmtime(float(date[0]) - date[1]))

changelog = []
for l in sys.stdin.readlines():
    tok = l.split("\t")
    hgdate = tuple(int(v) for v in tok[0].split())
    changelog.append((datestr(hgdate, "%F"), tok[1], hgdate, tok[2]))
prevtitle = ""
for l in sorted(changelog, reverse=True):
    title = "* %s %s" % (datestr(l[2], "%a %b %d %Y"), l[1])
    if prevtitle != title:
        prevtitle = title
        print
        print title
    print "- %s" % l[3].strip()
' >> $rpmspec

else

    $HG log \
         --template '{date|hgdate}\t{author}\t{desc|firstline}\n' \
         .hgtags | python -c '
import sys, time

def datestr(date, format):
    return time.strftime(format, time.gmtime(float(date[0]) - date[1]))

for l in sys.stdin.readlines():
    tok = l.split("\t")
    hgdate = tuple(int(v) for v in tok[0].split())
    print "* %s %s\n- %s" % (datestr(hgdate, "%a %b %d %Y"), tok[1], tok[2])
' >> $rpmspec

fi

sed -i \
    -e "s/^%define withpython.*$/%define withpython $RPMPYTHONVER/" \
    $rpmspec

if [ "$BUILD" ]; then
    rpmbuild --define "_topdir $RPMBUILDDIR" -ba $rpmspec --clean
    if [ $? = 0 ]; then
        echo
        echo "Built packages for $version-$release:"
        find $RPMBUILDDIR/*RPMS/ -type f -newer $rpmspec
    fi
else
    echo "Prepared sources for $version-$release $rpmspec are in $RPMBUILDDIR/SOURCES/ - use like:"
    echo "rpmbuild --define '_topdir $RPMBUILDDIR' -ba $rpmspec --clean"
fi