Bug#491633: Here is a (may be not correct but at least ) working preinst file
take your package in /var/cache/apt/archive
Do
1) dpkg-deb -x libxf-dev... /tmp/foo
2) dpkg-deb -e libxf-dev... /tmp/foo/DEBIAN
3) replace the files in /tmp/foo/DEBIAN with the one provided
4) rebuild the pacage by dpkg-deb -b /tmp/foo
5) install the new package
--eric
#!/bin/bash
# -*- coding: utf-8 -*-
# Preinst for libxft-dev
# Copyright © 2002 Colin Walters <walters@gnu.org>
# Copyright © 2003 Branden Robinson <branden@debian.org>
# $Id: libxft-dev.preinst 99 2004-03-11 07:12:41Z branden $
set -e
THIS_PACKAGE=libxft-dev
THIS_SCRIPT=preinst
if [ "$1" = "install" -o "$1" = "upgrade" ]; then
# Remove any diversions created by earlier versions of this package
# (libxft-dev), and any still present that were created by the previous
# name of this package (libxft2-dev).
for PKG in libxft-dev libxft2-dev; do
if dpkg-divert --list /usr/X11R6/include/X11/Xft/Xft.h | \
grep "\<$PKG\$"; then
dpkg-divert --package "$PKG" --remove --rename \
--divert /usr/X11R6/include/X11/Xft/Xft1.h \
/usr/X11R6/include/X11/Xft/Xft.h
fi
if dpkg-divert --list /usr/X11R6/lib/libXft.a | \
grep "\<$PKG\$"; then
dpkg-divert --package "$PKG" --remove --rename \
--divert /usr/X11R6/lib/libXft1.a /usr/X11R6/lib/libXft.a
fi
if dpkg-divert --list /usr/X11R6/lib/libXft.so | \
grep "\<$PKG\$"; then
dpkg-divert --package "$PKG" --remove --rename \
--divert /usr/X11R6/lib/libXft1.so /usr/X11R6/lib/libXft.so
fi
done
# The following diversion dates back to libxft2-dev << 2.1.1, but we have
# no way of knowing what version of a different package was on the system.
if dpkg-divert --list /usr/X11R6/include/X11/Xft/XftFreetype.h | \
grep '\<libxft2-dev$'; then
dpkg-divert --package libxft2-dev --remove --rename \
--divert /usr/X11R6/include/X11/Xft/XftFreetype1.h \
/usr/X11R6/include/X11/Xft/XftFreetype.h
fi
fi
# vim:set ai et sts=4 sw=4 tw=0:
# $Id$
# This is the X Strike Force shell library for X Window System package
# maintainer scripts. It serves to define shell functions commonly used by
# such packages, and performs some error checking necessary for proper operation
# of those functions. By itself, it does not "do" much; the maintainer scripts
# invoke the functions defined here to accomplish package installation and
# removal tasks.
# If you are reading this within a Debian package maintainer script (e.g.,
# /var/lib/dpkg)info/PACKAGE.{config,preinst,postinst,prerm,postrm}), you can
# skip past this library by scanning forward in this file to the string
# "GOBSTOPPER".
SOURCE_VERSION=2.1.13-1
OFFICIAL_BUILD=yes
# Use special abnormal exit codes so that problems with this library are more
# easily tracked down.
SHELL_LIB_INTERNAL_ERROR=86
SHELL_LIB_THROWN_ERROR=74
SHELL_LIB_USAGE_ERROR=99
# old -> new variable names
if [ -z "$DEBUG_XORG_PACKAGE" ] && [ -n "$DEBUG_XFREE86_PACKAGE" ]; then
DEBUG_XORG_PACKAGE="$DEBUG_XFREE86_PACKAGE"
fi
if [ -z "$DEBUG_XORG_DEBCONF" ] && [ -n "$DEBUG_XFREE86_DEBCONF" ]; then
DEBUG_XORG_DEBCONF="$DEBUG_XFREE86_DEBCONF"
fi
# initial sanity checks
if [ -z "$THIS_PACKAGE" ]; then
cat >&2 <<EOF
Error: package maintainer script attempted to use shell library without
definining \$THIS_PACKAGE shell variable. Please report the package name,
version, and the text of this error message to the Debian Bug Tracking System.
Visit <http://www.debian.org/Bugs/Reporting> on the World Wide Web for
instructions, read the file /usr/share/doc/debian/bug-reporting.txt from the
"doc-debian" package, or install the "reportbug" package and use the command of
the same name to file a report against version $SOURCE_VERSION of this package.
EOF
exit $SHELL_LIB_USAGE_ERROR
fi
if [ -z "$THIS_SCRIPT" ]; then
cat >&2 <<EOF
Error: package maintainer script attempted to use shell library without
definining \$THIS_SCRIPT shell variable. Please report the package name,
version, and the text of this error message to the Debian Bug Tracking System.
Visit <http://www.debian.org/Bugs/Reporting> on the World Wide Web for
instructions, read the file /usr/share/doc/debian/bug-reporting.txt from the
"doc-debian" package, or install the "reportbug" package and use the command of
the same name to file a report against version $SOURCE_VERSION of the
"$THIS_PACKAGE" package.
EOF
exit $SHELL_LIB_USAGE_ERROR
fi
ARCHITECTURE="$(dpkg --print-installation-architecture)"
if [ "$1" = "reconfigure" ] || [ -n "$DEBCONF_RECONFIGURE" ]; then
RECONFIGURE="true"
else
RECONFIGURE=
fi
if ([ "$1" = "install" ] || [ "$1" = "configure" ]) && [ -z "$2" ]; then
FIRSTINST="yes"
fi
if [ -z "$RECONFIGURE" ] && [ -z "$FIRSTINST" ]; then
UPGRADE="yes"
fi
trap "message;\
message \"Received signal. Aborting $THIS_PACKAGE package $THIS_SCRIPT script.\";\
message;\
exit 1" HUP INT QUIT TERM
reject_nondigits () {
# syntax: reject_nondigits [ operand ... ]
#
# scan operands (typically shell variables whose values cannot be trusted) for
# characters other than decimal digits and barf if any are found
while [ -n "$1" ]; do
# does the operand contain anything but digits?
if ! expr "$1" : "[[:digit:]]\+$" > /dev/null 2>&1; then
# can't use die(), because it wraps message() which wraps this function
echo "$THIS_PACKAGE $THIS_SCRIPT error: reject_nondigits() encountered" \
"possibly malicious garbage \"$1\"" >&2
exit $SHELL_LIB_THROWN_ERROR
fi
shift
done
}
reject_whitespace () {
# syntax: reject_whitespace [ operand ]
#
# scan operand (typically a shell variable whose value cannot be trusted) for
# whitespace characters and barf if any are found
if [ -n "$1" ]; then
# does the operand contain any whitespace?
if expr "$1" : "[[:space:]]" > /dev/null 2>&1; then
# can't use die(), because I want to avoid forward references
echo "$THIS_PACKAGE $THIS_SCRIPT error: reject_whitespace() encountered" \
"possibly malicious garbage \"$1\"" >&2
exit $SHELL_LIB_THROWN_ERROR
fi
fi
}
reject_unlikely_path_chars () {
# syntax: reject_unlikely_path_chars [ operand ... ]
#
# scan operands (typically shell variables whose values cannot be trusted) for
# characters unlikely to be seen in a path and which the shell might
# interpret and barf if any are found
while [ -n "$1" ]; do
# does the operand contain any funny characters?
if expr "$1" : '.*[!$&()*;<>?|].*' > /dev/null 2>&1; then
# can't use die(), because I want to avoid forward references
echo "$THIS_PACKAGE $THIS_SCRIPT error: reject_unlikely_path_chars()" \
"encountered possibly malicious garbage \"$1\"" >&2
exit $SHELL_LIB_THROWN_ERROR
fi
shift
done
}
# Query the terminal to establish a default number of columns to use for
# displaying messages to the user. This is used only as a fallback in the
# event the COLUMNS variable is not set. ($COLUMNS can react to SIGWINCH while
# the script is running, and this cannot, only being calculated once.)
DEFCOLUMNS=$(stty size 2> /dev/null | awk '{print $2}') || true
if ! expr "$DEFCOLUMNS" : "[[:digit:]]\+$" > /dev/null 2>&1; then
DEFCOLUMNS=80
fi
message () {
# pretty-print messages of arbitrary length
reject_nondigits "$COLUMNS"
echo "$*" | fmt -t -w ${COLUMNS:-$DEFCOLUMNS} >&2
}
observe () {
# syntax: observe message ...
#
# issue observational message suitable for logging someday when support for
# it exists in dpkg
if [ -n "$DEBUG_XORG_PACKAGE" ]; then
message "$THIS_PACKAGE $THIS_SCRIPT note: $*"
fi
}
warn () {
# syntax: warn message ...
#
# issue warning message suitable for logging someday when support for
# it exists in dpkg; also send to standard error
message "$THIS_PACKAGE $THIS_SCRIPT warning: $*"
}
die () {
# syntax: die message ...
#
# exit script with error message
message "$THIS_PACKAGE $THIS_SCRIPT error: $*"
exit $SHELL_LIB_THROWN_ERROR
}
internal_error () {
# exit script with error; essentially a "THIS SHOULD NEVER HAPPEN" message
message "internal error: $*"
if [ -n "$OFFICIAL_BUILD" ]; then
message "Please report a bug in the $THIS_SCRIPT script of the" \
"$THIS_PACKAGE package, version $SOURCE_VERSION to the Debian Bug" \
"Tracking System. Include all messages above that mention the" \
"$THIS_PACKAGE package. Visit " \
"<http://www.debian.org/Bugs/Reporting> on the World Wide Web for" \
"instructions, read the file" \
"/usr/share/doc/debian/bug-reporting.txt from the doc-debian" \
"package, or install the reportbug package and use the command of" \
"the same name to file a report."
fi
exit $SHELL_LIB_INTERNAL_ERROR
}
usage_error () {
message "usage error: $*"
message "Please report a bug in the $THIS_SCRIPT script of the" \
"$THIS_PACKAGE package, version $SOURCE_VERSION to the Debian Bug" \
"Tracking System. Include all messages above that mention the" \
"$THIS_PACKAGE package. Visit " \
"<http://www.debian.org/Bugs/Reporting> on the World Wide Web for" \
"instructions, read the file" \
"/usr/share/doc/debian/bug-reporting.txt from the doc-debian" \
"package, or install the reportbug package and use the command of" \
"the same name to file a report."
exit $SHELL_LIB_USAGE_ERROR
}
maplink () {
# returns what symlink should point to; i.e., what the "sane" answer is
# Keep this in sync with the debian/*.links files.
# This is only needed for symlinks to directories.
#
# XXX: Most of these look wrong in the X11R7 world and need to be fixed.
# If we've stopped using this function, fixing it might enable us to re-enable
# it again and catch more errors.
case "$1" in
/etc/X11/xkb/compiled) echo /var/lib/xkb ;;
/etc/X11/xkb/xkbcomp) echo /usr/X11R6/bin/xkbcomp ;;
/usr/X11R6/lib/X11/app-defaults) echo /etc/X11/app-defaults ;;
/usr/X11R6/lib/X11/fs) echo /etc/X11/fs ;;
/usr/X11R6/lib/X11/lbxproxy) echo /etc/X11/lbxproxy ;;
/usr/X11R6/lib/X11/proxymngr) echo /etc/X11/proxymngr ;;
/usr/X11R6/lib/X11/rstart) echo /etc/X11/rstart ;;
/usr/X11R6/lib/X11/twm) echo /etc/X11/twm ;;
/usr/X11R6/lib/X11/xdm) echo /etc/X11/xdm ;;
/usr/X11R6/lib/X11/xinit) echo /etc/X11/xinit ;;
/usr/X11R6/lib/X11/xkb) echo /etc/X11/xkb ;;
/usr/X11R6/lib/X11/xserver) echo /etc/X11/xserver ;;
/usr/X11R6/lib/X11/xsm) echo /etc/X11/xsm ;;
/usr/bin/X11) echo ../X11R6/bin ;;
/usr/bin/rstartd) echo ../X11R6/bin/rstartd ;;
/usr/include/X11) echo ../X11R6/include/X11 ;;
/usr/lib/X11) echo ../X11R6/lib/X11 ;;
*) internal_error "maplink() called with unknown path \"$1\"" ;;
esac
}
analyze_path () {
# given a supplied set of pathnames, break each one up by directory and do an
# ls -dl on each component, cumulatively; i.e.
# analyze_path /usr/X11R6/bin -> ls -dl /usr /usr/X11R6 /usr/X11R6/bin
# Thanks to Randolph Chung for this clever hack.
local f g
while [ -n "$1" ]; do
reject_whitespace "$1"
g=
message "Analyzing $1:"
for f in $(echo "$1" | tr / \ ); do
if [ -e /$g$f ]; then
ls -dl /$g$f /$g$f.dpkg-* 2> /dev/null || true
g=$g$f/
else
message "/$g$f: nonexistent; directory contents of /$g:"
ls -l /$g
break
fi
done
shift
done
}
find_culprits () {
local f p dpkg_info_dir possible_culprits smoking_guns bad_packages package \
msg
reject_whitespace "$1"
message "Searching for overlapping packages..."
dpkg_info_dir=/var/lib/dpkg/info
if [ -d $dpkg_info_dir ]; then
if [ "$(echo $dpkg_info_dir/*.list)" != "$dpkg_info_dir/*.list" ]; then
possible_culprits=$(ls -1 $dpkg_info_dir/*.list | egrep -v \
"(xbase-clients|x11-common|xfs|xlibs)")
if [ -n "$possible_culprits" ]; then
smoking_guns=$(grep -l "$1" $possible_culprits || true)
if [ -n "$smoking_guns" ]; then
bad_packages=$(printf "\\n")
for f in $smoking_guns; do
# too bad you can't nest parameter expansion voodoo
p=${f%*.list} # strip off the trailing ".list"
package=${p##*/} # strip off the directories
bad_packages=$(printf "%s\n%s" "$bad_packages" "$package")
done
msg=$(cat <<EOF
The following packages appear to have file overlaps with the X.Org packages;
these packages are either very old, or in violation of Debian Policy. Try
upgrading each of these packages to the latest available version if possible:
for example, with the command "apt-get install". If no newer version of a
package is available, you will have to remove it; for example, with the command
"apt-get remove". If even the latest available version of the package has
this file overlap, please file a bug against that package with the Debian Bug
Tracking System. You may want to refer the package maintainer to section 12.8
of the Debian Policy manual.
EOF
)
message "$msg"
message "The overlapping packages are: $bad_packages"
else
message "no overlaps found."
fi
fi
else
message "cannot search; no matches for $dpkg_info_dir/*.list."
fi
else
message "cannot search; $dpkg_info_dir does not exist."
fi
}
# we require a readlink command or shell function
if ! which readlink > /dev/null 2>&1; then
message "The readlink command was not found. Please install version" \
"1.13.1 or later of the debianutils package."
readlink () {
# returns what symlink in $1 actually points to
perl -e '$l = shift; exit 1 unless -l $l; $r = readlink $l; exit 1 unless $r; print "$r\n"' "$1"
}
fi
check_symlink () {
# syntax: check_symlink symlink
#
# See if specified symlink points where it is supposed to. Return 0 if it
# does, and 1 if it does not.
#
# Primarily used by check_symlinks_and_warn() and check_symlinks_and_bomb().
local symlink
# validate arguments
if [ $# -ne 1 ]; then
usage_error "check_symlink() called with wrong number of arguments;" \
"expected 1, got $#"
exit $SHELL_LIB_USAGE_ERROR
fi
symlink="$1"
if [ "$(maplink "$symlink")" = "$(readlink "$symlink")" ]; then
return 0
else
return 1
fi
}
check_symlinks_and_warn () {
# syntax: check_symlinks_and_warn symlink ...
#
# For each argument, check for symlink sanity, and warn if it isn't sane.
#
# Call this function from a preinst script in the event $1 is "upgrade" or
# "install".
local errmsg symlink
# validate arguments
if [ $# -lt 1 ]; then
usage_error "check_symlinks_and_warn() called with wrong number of" \
"arguments; expected at least 1, got $#"
exit $SHELL_LIB_USAGE_ERROR
fi
while [ -n "$1" ]; do
symlink="$1"
if [ -L "$symlink" ]; then
if ! check_symlink "$symlink"; then
observe "$symlink symbolic link points to wrong location" \
"$(readlink "$symlink"); removing"
rm "$symlink"
fi
elif [ -e "$symlink" ]; then
errmsg="$symlink exists and is not a symbolic link; this package cannot"
errmsg="$errmsg be installed until this"
if [ -f "$symlink" ]; then
errmsg="$errmsg file"
elif [ -d "$symlink" ]; then
errmsg="$errmsg directory"
else
errmsg="$errmsg thing"
fi
errmsg="$errmsg is removed"
die "$errmsg"
fi
shift
done
}
check_symlinks_and_bomb () {
# syntax: check_symlinks_and_bomb symlink ...
#
# For each argument, check for symlink sanity, and bomb if it isn't sane.
#
# Call this function from a postinst script.
local problem symlink
# validate arguments
if [ $# -lt 1 ]; then
usage_error "check_symlinks_and_bomb() called with wrong number of"
"arguments; expected at least 1, got $#"
exit $SHELL_LIB_USAGE_ERROR
fi
while [ -n "$1" ]; do
problem=
symlink="$1"
if [ -L "$symlink" ]; then
if ! check_symlink "$symlink"; then
problem=yes
warn "$symlink symbolic link points to wrong location" \
"$(readlink "$symlink")"
fi
elif [ -e "$symlink" ]; then
problem=yes
warn "$symlink is not a symbolic link"
else
problem=yes
warn "$symlink symbolic link does not exist"
fi
if [ -n "$problem" ]; then
analyze_path "$symlink" "$(readlink "$symlink")"
find_culprits "$symlink"
die "bad symbolic links on system"
fi
shift
done
}
font_update () {
# run $UPDATECMDS in $FONTDIRS
local dir cmd shortcmd x_font_dir_prefix
x_font_dir_prefix="/usr/share/fonts/X11"
if [ -z "$UPDATECMDS" ]; then
usage_error "font_update() called but \$UPDATECMDS not set"
fi
if [ -z "$FONTDIRS" ]; then
usage_error "font_update() called but \$FONTDIRS not set"
fi
reject_unlikely_path_chars "$UPDATECMDS"
reject_unlikely_path_chars "$FONTDIRS"
for dir in $FONTDIRS; do
if [ -d "$x_font_dir_prefix/$dir" ]; then
for cmd in $UPDATECMDS; do
if which "$cmd" > /dev/null 2>&1; then
shortcmd=${cmd##*/}
observe "running $shortcmd in $dir font directory"
cmd_opts=
if [ "$shortcmd" = "update-fonts-alias" ]; then
cmd_opts=--x11r7-layout
fi
if [ "$shortcmd" = "update-fonts-dir" ]; then
cmd_opts=--x11r7-layout
fi
if [ "$shortcmd" = "update-fonts-scale" ]; then
cmd_opts=--x11r7-layout
fi
$cmd $cmd_opts $dir || warn "$cmd $cmd_opts $dir" \
"failed; font directory data may not" \
"be up to date"
else
warn "$cmd not found; not updating corresponding $dir font" \
"directory data"
fi
done
else
warn "$dir is not a directory; not updating font directory data"
fi
done
}
remove_conffile_prepare () {
# syntax: remove_conffile_prepare filename official_md5sum ...
#
# Check a conffile "filename" against a list of canonical MD5 checksums.
# If the file's current MD5 checksum matches one of the "official_md5sum"
# operands provided, then prepare the conffile for removal from the system.
# We defer actual deletion until the package is configured so that we can
# roll this operation back if package installation fails.
#
# Call this function from a preinst script in the event $1 is "upgrade" or
# "install" and verify $2 to ensure the package is being upgraded from a
# version (or installed over a version removed-but-not-purged) prior to the
# one in which the conffile was obsoleted.
local conffile current_checksum
# validate arguments
if [ $# -lt 2 ]; then
usage_error "remove_conffile_prepare() called with wrong number of" \
"arguments; expected at least 2, got $#"
exit $SHELL_LIB_USAGE_ERROR
fi
conffile="$1"
shift
# does the conffile even exist?
if [ -e "$conffile" ]; then
# calculate its checksum
current_checksum=$(md5sum < "$conffile" | sed 's/[[:space:]].*//')
# compare it to each supplied checksum
while [ -n "$1" ]; do
if [ "$current_checksum" = "$1" ]; then
# we found a match; move the confffile and stop looking
observe "preparing obsolete conffile $conffile for removal"
mv "$conffile" "$conffile.$THIS_PACKAGE-tmp"
break
fi
shift
done
fi
}
remove_conffile_lookup () {
# syntax: remove_conffile_lookup package filename
#
# Lookup the md5sum of a conffile in dpkg's database, and prepare for removal
# if it matches the actual file's md5sum.
#
# Call this function when you would call remove_conffile_prepare but only
# want to check against dpkg's status database instead of known checksums.
local package conffile old_md5sum
# validate arguments
if [ $# -ne 2 ]; then
usage_error "remove_conffile_lookup() called with wrong number of" \
"arguments; expected 1, got $#"
exit $SHELL_LIB_USAGE_ERROR
fi
package="$1"
conffile="$2"
if ! [ -e "$conffile" ]; then
return
fi
old_md5sum="$(dpkg-query -W -f='${Conffiles}' "$package" | \
awk '{ if (match($0, "^ '"$conffile"' ")) print $2}')"
if [ -n "$old_md5sum" ]; then
remove_conffile_prepare "$conffile" "$old_md5sum"
fi
}
remove_conffile_commit () {
# syntax: remove_conffile_commit filename
#
# Complete the removal of a conffile "filename" that has become obsolete.
#
# Call this function from a postinst script after having used
# remove_conffile_prepare() in the preinst.
local conffile
# validate arguments
if [ $# -ne 1 ]; then
usage_error "remove_conffile_commit() called with wrong number of" \
"arguments; expected 1, got $#"
exit $SHELL_LIB_USAGE_ERROR
fi
conffile="$1"
# if the temporary file created by remove_conffile_prepare() exists, remove it
if [ -e "$conffile.$THIS_PACKAGE-tmp" ]; then
observe "committing removal of obsolete conffile $conffile"
rm "$conffile.$THIS_PACKAGE-tmp"
fi
}
remove_conffile_rollback () {
# syntax: remove_conffile_rollback filename
#
# Roll back the removal of a conffile "filename".
#
# Call this function from a postrm script in the event $1 is "abort-upgrade"
# or "abort-install" is after having used remove_conffile_prepare() in the
# preinst.
local conffile
# validate arguments
if [ $# -ne 1 ]; then
usage_error "remove_conffile_rollback() called with wrong number of" \
"arguments; expected 1, got $#"
exit $SHELL_LIB_USAGE_ERROR
fi
conffile="$1"
# if the temporary file created by remove_conffile_prepare() exists, move it
# back
if [ -e "$conffile.$THIS_PACKAGE-tmp" ]; then
observe "rolling back removal of obsolete conffile $conffile"
mv "$conffile.$THIS_PACKAGE-tmp" "$conffile"
fi
}
replace_conffile_with_symlink_prepare () {
# syntax: replace_conffile_with_symlink_prepare oldfilename newfilename \
# official_md5sum ...
#
# Check a conffile "oldfilename" against a list of canonical MD5 checksums.
# If the file's current MD5 checksum matches one of the "official_md5sum"
# operands provided, then prepare the conffile for removal from the system.
# We defer actual deletion until the package is configured so that we can
# roll this operation back if package installation fails. Otherwise copy it
# to newfilename and let dpkg handle it through conffiles mechanism.
#
# Call this function from a preinst script in the event $1 is "upgrade" or
# "install" and verify $2 to ensure the package is being upgraded from a
# version (or installed over a version removed-but-not-purged) prior to the
# one in which the conffile was obsoleted.
local conffile current_checksum
# validate arguments
if [ $# -lt 3 ]; then
usage_error "replace_conffile_with_symlink_prepare() called with wrong" \
" number of arguments; expected at least 3, got $#"
exit $SHELL_LIB_USAGE_ERROR
fi
oldconffile="$1"
shift
newconffile="$1"
shift
remove_conffile_prepare "$_oldconffile" "$@"
# If $oldconffile still exists, then md5sums didn't match.
# Copy it to new one.
if [ -f "$oldconffile" ]; then
cp "$oldconffile" "$newconffile"
fi
}
replace_conffile_with_symlink_commit () {
# syntax: replace_conffile_with_symlink_commit oldfilename
#
# Complete the removal of a conffile "oldfilename" that has been
# replaced by a symlink.
#
# Call this function from a postinst script after having used
# replace_conffile_with_symlink_prepare() in the preinst.
local conffile
# validate arguments
if [ $# -ne 1 ]; then
usage_error "replace_conffile_with_symlink_commit() called with wrong" \
"number of arguments; expected 1, got $#"
exit $SHELL_LIB_USAGE_ERROR
fi
conffile="$1"
remove_conffile_commit "$conffile"
}
replace_conffile_with_symlink_rollback () {
# syntax: replace_conffile_with_symlink_rollback oldfilename newfilename
#
# Roll back the replacing of a conffile "oldfilename" with symlink to
# "newfilename".
#
# Call this function from a postrm script in the event $1 is "abort-upgrade"
# or "abort-install" and verify $2 to ensure the package failed to upgrade
# from a version (or install over a version removed-but-not-purged) prior
# to the one in which the conffile was obsoleted.
# You should have used replace_conffile_with_symlink_prepare() in the
# preinst.
local conffile
# validate arguments
if [ $# -ne 2 ]; then
usage_error "replace_conffile_with_symlink_rollback() called with wrong" \
"number of arguments; expected 2, got $#"
exit $SHELL_LIB_USAGE_ERROR
fi
oldconffile="$1"
newconffile="$2"
remove_conffile_rollback "$_oldconffile"
if [ -f "$newconffile" ]; then
rm "$newconffile"
fi
}
run () {
# syntax: run command [ argument ... ]
#
# Run specified command with optional arguments and report its exit status.
# Useful for commands whose exit status may be nonzero, but still acceptable,
# or commands whose failure is not fatal to us.
#
# NOTE: Do *not* use this function with db_get or db_metaget commands; in
# those cases the return value of the debconf command *must* be checked
# before the string returned by debconf is used for anything.
local retval
# validate arguments
if [ $# -lt 1 ]; then
usage_error "run() called with wrong number of arguments; expected at" \
"least 1, got $#"
exit $SHELL_LIB_USAGE_ERROR
fi
"$@" || retval=$?
if [ ${retval:-0} -ne 0 ]; then
observe "command \"$*\" exited with status $retval"
fi
}
register_x_lib_dir_with_ld_so () {
# syntax: register_x_lib_dir_with_ld_so
#
# Configure the dynamic loader ld.so to search /usr/X11R6/lib for shared
# libraries.
#
# Call this function from the postinst script of a package that places a
# shared library in /usr/X11R6/lib, before invoking ldconfig.
local dir ldsoconf
dir="/usr/X11R6/lib"
ldsoconf="/etc/ld.so.conf"
# is the line not already present?
if ! fgrep -qsx "$dir" "$ldsoconf"; then
observe "adding $dir directory to $ldsoconf"
echo "$dir" >> "$ldsoconf"
fi
}
deregister_x_lib_dir_with_ld_so () {
# syntax: deregister_x_lib_dir_with_ld_so
#
# Configure dynamic loader ld.so to not search /usr/X11R6/lib for shared
# libraries, if and only if no shared libaries remain there.
#
# Call this function from the postrm script of a package that places a shared
# library in /usr/X11R6/lib, in the event "$1" is "remove", and before
# invoking ldconfig.
local dir ldsoconf fgrep_status cmp_status
dir="/usr/X11R6/lib"
ldsoconf="/etc/ld.so.conf"
# is the line present?
if fgrep -qsx "$dir" "$ldsoconf"; then
# are there any shared objects in the directory?
if [ "$(echo "$dir"/lib*.so.*.*)" = "$dir/lib*.so.*.*" ]; then
# glob expansion produced nothing, so no shared libraries are present
observe "removing $dir directory from $ldsoconf"
# rewrite the file (very carefully)
set +e
fgrep -svx "$dir" "$ldsoconf" > "$ldsoconf.dpkg-tmp"
fgrep_status=$?
set -e
case $fgrep_status in
0|1) ;; # we don't actually care if any lines matched or not
*) die "error reading \"$ldsoconf\"; fgrep exited with status" \
"$fgrep_status" ;;
esac
set +e
cmp -s "$ldsoconf.dpkg-tmp" "$ldsoconf"
cmp_status=$?
set -e
case $cmp_status in
0) rm "$ldsoconf.dpkg-tmp" ;; # files are identical
1) mv "$ldsoconf.dpkg-tmp" "$ldsoconf" ;; # files differ
*) die "error comparing \"$ldsoconf.dpkg-tmp\" to \"$ldsoconf\";" \
"cmp exited with status $cmp_status" ;;
esac
fi
fi
}
make_symlink_sane () {
# syntax: make_symlink_sane symlink target
#
# Ensure that the symbolic link symlink exists, and points to target.
#
# If symlink does not exist, create it and point it at target.
#
# If symlink exists but is not a symbolic link, back it up.
#
# If symlink exists, is a symbolic link, but points to the wrong location, fix
# it.
#
# If symlink exists, is a symbolic link, and already points to target, do
# nothing.
#
# This function wouldn't be needed if ln had an -I, --idempotent option.
# Validate arguments.
if [ $# -ne 2 ]; then
usage_error "make_symlink_sane() called with wrong number of arguments;" \
"expected 2, got $#"
exit $SHELL_LIB_USAGE_ERROR
fi
# We could just use the positional parameters as-is, but that makes things
# harder to follow.
local symlink target
symlink="$1"
target="$2"
if [ -L "$symlink" ] && [ "$(readlink "$symlink")" = "$target" ]; then
observe "link from $symlink to $target already exists"
else
observe "creating symbolic link from $symlink to $target"
mkdir -p "${target%/*}" "${symlink%/*}"
ln -s -b -S ".dpkg-old" "$target" "$symlink"
fi
}
migrate_dir_to_symlink () {
# syntax: migrate_dir_to_symlink old_location new_location
#
# Per Debian Policy section 6.5.4, "A directory will never be replaced by a
# symbolic link to a directory or vice versa; instead, the existing state
# (symlink or not) will be left alone and dpkg will follow the symlink if
# there is one."
#
# We have to do it ourselves.
#
# This function moves the contents of old_location, a directory, into
# new_location, a directory, then makes old_location a symbolic link to
# new_location.
#
# old_location need not exist, but if it does, it must be a directory (or a
# symlink to a directory). If it is not, it is backed up. If new_location
# exists already and is not a directory, it is backed up.
#
# This function should be called from a package's preinst so that other
# packages unpacked after this one --- but before this package's postinst runs
# --- are unpacked into new_location even if their payloads contain
# old_location filespecs.
# Validate arguments.
if [ $# -ne 2 ]; then
usage_error "migrate_dir_to_symlink() called with wrong number of"
"arguments; expected 2, got $#"
exit $SHELL_LIB_USAGE_ERROR
fi
# We could just use the positional parameters as-is, but that makes things
# harder to follow.
local new old
old="$1"
new="$2"
# Is old location a symlink?
if [ -L "$old" ]; then
# Does it already point to new location?
if [ "$(readlink "$old")" = "$new" ]; then
# Nothing to do; migration has already been done.
observe "migration of $old to $new already done"
return 0
else
# Back it up.
warn "backing up symbolic link $old as $old.dpkg-old"
mv -b "$old" "$old.dpkg-old"
fi
fi
# Does old location exist, but is not a directory?
if [ -e "$old" ] && ! [ -d "$old" ]; then
# Back it up.
warn "backing up non-directory $old as $old.dpkg-old"
mv -b "$old" "$old.dpkg-old"
fi
observe "migrating $old to $new"
# Is new location a symlink?
if [ -L "$new" ]; then
# Does it point the wrong way, i.e., back to where we're migrating from?
if [ "$(readlink "$new")" = "$old" ]; then
# Get rid of it.
observe "removing symbolic link $new which points to $old"
rm "$new"
else
# Back it up.
warn "backing up symbolic link $new as $new.dpkg-old"
mv -b "$new" "$new.dpkg-old"
fi
fi
# Does new location exist, but is not a directory?
if [ -e "$new" ] && ! [ -d "$new" ]; then
warn "backing up non-directory $new as $new.dpkg-old"
mv -b "$new" "$new.dpkg-old"
fi
# Create new directory if it does not yet exist.
if ! [ -e "$new" ]; then
observe "creating $new"
mkdir -p "$new"
fi
# Copy files in old location to new location. Back up any filenames that
# already exist in the new location with the extension ".dpkg-old".
observe "copying files from $old to $new"
if ! (cd "$old" && cp -a -b -S ".dpkg-old" . "$new"); then
die "error(s) encountered while copying files from $old to $new"
fi
# Remove files at old location.
observe "removing $old"
rm -r "$old"
# Create symlink from old location to new location.
make_symlink_sane "$old" "$new"
}
# vim:set ai et sw=2 ts=2 tw=80:
# GOBSTOPPER: The X Strike Force shell library ends here.
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