Mercurial > hg > octave-lyh > gnulib-hg
changeset 9799:55aec4615f6d
New script and module: mktempd
* MODULES.html.sh (maint+release support): Add mktempd.
* build-aux/mktempd: New file.
* modules/mktempd: New file.
author | Jim Meyering <meyering@redhat.com> |
---|---|
date | Tue, 18 Mar 2008 16:19:27 +0100 |
parents | 28150ef22b48 |
children | b2c65dc6be73 |
files | ChangeLog MODULES.html.sh build-aux/mktempd modules/mktempd |
diffstat | 4 files changed, 159 insertions(+), 0 deletions(-) [+] |
line wrap: on
line diff
--- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,10 @@ +2008-03-18 Jim Meyering <meyering@redhat.com> + + New script and module: mktempd + * MODULES.html.sh (maint+release support): Add mktempd. + * build-aux/mktempd: New file. + * modules/mktempd: New file. + 2008-03-15 Jim Meyering <meyering@redhat.com> Undo last change.
--- a/MODULES.html.sh +++ b/MODULES.html.sh @@ -2737,6 +2737,7 @@ func_module gitlog-to-changelog func_module gnupload func_module maintainer-makefile + func_module mktempd func_module useless-if-before-free func_module vc-list-files func_end_table
new file mode 100755 --- /dev/null +++ b/build-aux/mktempd @@ -0,0 +1,132 @@ +#!/bin/sh +# Create a temporary directory, much like mktemp -d does. + +# Copyright (C) 2007-2008 Free Software Foundation, Inc. + +# This program is free software: you can redistribute it and/or modify +# it under the terms of the GNU General Public License as published by +# the Free Software Foundation, either version 3 of the License, or +# (at your option) any later version. + +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. + +# You should have received a copy of the GNU General Public License +# along with this program. If not, see <http://www.gnu.org/licenses/>. + +# Written by Jim Meyering. + +# Usage: mktempd /tmp phoey.XXXXXXXXXX + +# First, try to use the mktemp program. +# Failing that, we'll roll our own mktemp-like function: +# - try to get random bytes from /dev/urandom +# - failing that, generate output from a combination of quickly-varying +# sources and gzip. Ignore non-varying gzip header, and extract +# "random" bits from there. +# - given those bits, map to file-name bytes using tr, and try to create +# the desired directory. +# - make only $MAX_TRIES attempts + +ME=`basename "$0"` +die() { echo >&2 "$ME: $@"; exit 1; } + +MAX_TRIES=4 + +rand_bytes() +{ + n=$1 + + chars=abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789 + + dev_rand=/dev/urandom + if test -r "$dev_rand"; then + # Note: 256-length($chars) == 194; 3 copies of $chars is 186 + 8 = 194. + head -c$n "$dev_rand" | tr -c $chars 01234567$chars$chars$chars + return + fi + + cmds='date; date +%N; free; who -a; w; ps auxww; ps ef; netstat -n' + data=` (eval "$cmds") 2>&1 | gzip ` + + n_plus_50=`expr $n + 50` + + # Ensure that $data has length at least 50+$n + while :; do + len=`echo "$data"|wc -c` + test $n_plus_50 -le $len && break; + data=` (echo "$data"; eval "$cmds") 2>&1 | gzip ` + done + + echo "$data" \ + | dd bs=1 skip=50 count=$n 2>/dev/null \ + | tr -c $chars 01234567$chars$chars$chars +} + +mktempd() +{ + case $# in + 2);; + *) die "Usage: $ME DIR TEMPLATE";; + esac + + destdir=$1 + template=$2 + + # Disallow any trailing slash on specified destdir: + # it would subvert the post-mktemp "case"-based destdir test. + case $destdir in + /) ;; + */) die "invalid destination dir: remove trailing slash(es)";; + esac + + case $template in + *XXXX) ;; + *) die "invalid template: $template (must have a suffix of at least 4 X's)";; + esac + + fail=0 + + # First, try to use mktemp. + d=`env -u TMPDIR mktemp -d -t -p "$destdir" "$template" 2>/dev/null` \ + || fail=1 + + # The resulting name must be in the specified directory. + case $d in "$destdir"*);; *) fail=1;; esac + + # It must have created the directory. + test -d "$d" || fail=1 + + # It must have 0700 permissions. Handle sticky "S" bits. + perms=`ls -dgo "$d" 2>/dev/null|tr S -` || fail=1 + case $perms in drwx------*) ;; *) fail=1;; esac + + test $fail = 0 && { + echo "$d" + return + } + + # If we reach this point, we'll have to create a directory manually. + + # Get a copy of the template without its suffix of X's. + base_template=`echo "$template"|sed 's/XX*$//'` + + # Calculate how many X's we've just removed. + nx=`expr length "$template" - length "$base_template"` + + err= + i=1 + while :; do + X=`rand_bytes $nx` + candidate_dir="$destdir/$base_template$X" + err=`mkdir -m 0700 "$candidate_dir" 2>&1` \ + && { echo "$candidate_dir"; return; } + test $MAX_TRIES -le $i && break; + i=`expr $i + 1` + done + die "$err" +} + +mktempd "$@"