2 Commits

Author	SHA1	Message	Date
Alexey Tourbin	347a9eb418	symlinks.req: do only one single step of symlink resolution	2007-11-17 10:52:57 +03:00
Alexey Tourbin	9693c85f52	implemented symlinks.req ... Consider R-devel package, which has its own private bin/ directory, where it keeps certain scripts. $ rpm -ql R-devel |grep libtool /usr/lib/R/bin/libtool $ rpm -ql R-devel |grep texi2dvi /usr/lib/R/bin/texi2dvi $ I replace some scripts, such as libtool, with wrappers: $ tail -1 /usr/lib/R/bin/libtool exec /usr/bin/libtool "$@" $ R-devel now has a libtool dependency, generated by shell.req: $ rpm -qR R-devel |grep libtool libtool-common $ rpm -qf /usr/bin/libtool libtool-common-0.2-alt1 $ However, I want the very same dependency SIMPLY BY PLACING SYMBOLIC LINK to /usr/bin/libtool. My new script symlinks.req implements this idea. It works as follows: 1) We check all absolute symbolic links, e.g. -> /usr/bin/libtool. If symbolic link is absolute, we fetch its value and feed to FindPackage. Note that FindPackage will first check whether e.g. /usr/bin/libtool is available under RPM_BUILD_ROOT. 2) We also check all broken symbolic links, e.g. -> ../../../bin/libtool. The fact that symbolic link is broken means that it cannot be resolved into buildroot and otherwise must be resolved in the host system after the package is installed, which is the dependency on where it would point to after install. This means we must canonicalize the link value, strip RPM_BUILD_ROOT, and then call FindPackage. Here is what happens: $ cd `mktemp -d` $ RPM_BUILD_ROOT=$PWD $ mkdir -p ./usr/lib/R/bin/ $ ln -s `relative /usr/bin/libtool /usr/lib/R/bin/libtool` $RPM_BUILD_ROOT/usr/lib/R/bin/libtool $ l $RPM_BUILD_ROOT/usr/lib/R/bin/libtool lrwxrwxrwx 1 at at 20 Mar 9 22:14 /tmp/.private/at/tmp.AHnBX26473/usr/lib/R/bin/libtool -> ../../../bin/libtool $ [ -e $RPM_BUILD_ROOT/usr/lib/R/bin/libtool ] || echo broken broken $ readlink -vm $RPM_BUILD_ROOT/usr/lib/R/bin/libtool /tmp/.private/at/tmp.AHnBX26473/usr/bin/libtool $ to=`!!`; echo ${to#$RPM_BUILD_ROOT} /usr/bin/libtool $ And then FindPackage is called with "/usr/bin/libtool". Now note that if FindPackage is not able to associate e.g. /usr/bin/libtool with any particular rpm package, it will just place raw dependency on /usr/bin/libtool. So, this new type of dependencies is a bit dangerous: basically for each really broken symbolic link there will be an unmet dependency. On the other hand, this can be viewed as a means of protection from packages with really broken symbolic links. If you are frightened with this brand new and dangerous type of dependencies, please also note that this new type of dependencies is not much more dangerous than absolute paths to executables in plain shell scripts. $ /usr/lib/rpm/shell.req -v /dev/stdin <<</i/am/unmet error: file /i/am/unmet: No such file or directory shell.req: /dev/stdin: /i/am/unmet -> /i/am/unmet (raw, not found) /i/am/unmet $	2007-03-12 15:06:09 +03:00