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* Create a /tmp with 1777 permission in the chroot. Some builders

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need a writable /tmp (they don't respect $TMPDIR).
This commit is contained in:
Eelco Dolstra 2008-08-27 16:03:03 +00:00
parent 99dc3e613a
commit 9cc0da8453
1 changed files with 32 additions and 12 deletions
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44
src/libstore/build.cc
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@ -715,12 +715,15 @@ private:
/* Whether we're currently doing a chroot build. */
bool useChroot;
/* A RAII object to delete the chroot directory. */
boost::shared_ptr<AutoDelete> autoDelChroot;
/* RAII objects to delete the chroot directory and its /tmp
directory. Don't change the order: autoDelChrootTmp has to be
deleted before autoDelChrootRoot. */
boost::shared_ptr<AutoDelete> autoDelChrootRoot;
boost::shared_ptr<AutoDelete> autoDelChrootTmp;
/* In chroot builds, the list of bind mounts currently active.
The destructor of BindMount will cause the binds to be
unmounted. */
unmounted. Keep this *below* autoDelChroot* just to be safe! */
list<boost::shared_ptr<BindMount> > bindMounts;
typedef void (DerivationGoal::*GoalState)();
@ -1692,7 +1695,7 @@ void DerivationGoal::startBuilder()
work properly. Purity checking for fixed-output derivations
is somewhat pointless anyway. */
useChroot = queryBoolSetting("build-use-chroot", false);
Path tmpRootDir;
Path chrootRootDir;
if (fixedOutput) useChroot = false;
@ -1706,22 +1709,39 @@ void DerivationGoal::startBuilder()
/tmp/chroot-nix-*" to clean up aborted builds, and if some
of the bind-mounts are still active, then "rm -rf" will
happily recurse into those mount points (thereby deleting,
say, /nix/store). Ideally, tmpRootDir should be created in
say, /nix/store). Ideally, chrootRootDir should be created in
some special location (maybe in /nix/var/nix) where Nix
takes care of unmounting / deleting old chroots
automatically. */
tmpRootDir = createTempDir("", "chroot-nix");
chrootRootDir = createTempDir("", "chroot-nix");
/* Clean up the chroot directory automatically, but don't
recurse; that would be very very bad if the unmount of a
bind-mount fails. Instead BindMount::unbind() unmounts and
deletes exactly those directories that it created to
produce the mount point, so that after all the BindMount
destructors have run, tmpRootDir should be empty. */
autoDelChroot = boost::shared_ptr<AutoDelete>(new AutoDelete(tmpRootDir, false));
destructors have run, chrootRootDir should be empty. */
autoDelChrootRoot = boost::shared_ptr<AutoDelete>(new AutoDelete(chrootRootDir, false));
printMsg(lvlChatty, format("setting up chroot environment in `%1%'") % tmpRootDir);
printMsg(lvlChatty, format("setting up chroot environment in `%1%'") % chrootRootDir);
/* Create a writable /tmp in the chroot. Many builders need
this. (Of course they should really respect $TMPDIR
instead.) */
Path chrootTmpDir = chrootRootDir + "/tmp";
createDirs(chrootTmpDir);
if (chmod(chrootTmpDir.c_str(), 01777) == -1)
throw SysError("creating /tmp in the chroot");
/* When deleting this, do recurse (the builder might have left
crap there). As long as nothing important is bind-mounted
under /tmp it's okay (and the bind-mounts are unmounted
before autoDelChrootTmp's destructor runs, anyway). */
autoDelChrootTmp = boost::shared_ptr<AutoDelete>(new AutoDelete(chrootTmpDir));
/* Bind-mount a user-configurable set of directories from the
host file system. */
Paths defaultDirs;
defaultDirs.push_back("/dev");
defaultDirs.push_back("/proc");
@ -1734,7 +1754,7 @@ void DerivationGoal::startBuilder()
unmounted in LIFO order. (!!! Does the C++ standard
guarantee that list elements are destroyed in order?) */
for (Paths::iterator i = dirsInChroot.begin(); i != dirsInChroot.end(); ++i)
bindMounts.push_front(boost::shared_ptr<BindMount>(new BindMount(*i, tmpRootDir + *i)));
bindMounts.push_front(boost::shared_ptr<BindMount>(new BindMount(*i, chrootRootDir + *i)));
#else
throw Error("chroot builds are not supported on this platform");
@ -1773,8 +1793,8 @@ void DerivationGoal::startBuilder()
chroot. (Actually the order doesn't matter, since due
to the bind mount tmpDir and tmpRootDit/tmpDir are the
same directories.) */
if (useChroot && chroot(tmpRootDir.c_str()) == -1)
throw SysError(format("cannot change root directory to `%1%'") % tmpRootDir);
if (useChroot && chroot(chrootRootDir.c_str()) == -1)
throw SysError(format("cannot change root directory to `%1%'") % chrootRootDir);
#endif
initChild();