Commit Graph

12 Commits

Author SHA1 Message Date
Charles Hardin
2a9ef1f572 support/scripts: handle paths with regex characters in per-package
Some constraints on a setup ended up with a plus sign in the path
for historical reasons and would then fail to match on the comparison
of the host/lib dir match. So, the =~ for bash can be augmented
with a double quote expansion to preserve the literal value of
the characters in the variable.

Example Path: /home/vagrant/test+buildroot/per-package

Signed-off-by: Charles Hardin <ckhardin@gmail.com>
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>
2022-06-04 09:55:34 +02:00
Thomas Petazzoni
c4e6d5c8be core: implement per-package SDK and target
This commit implements the core of the move to per-package SDK and
target directories. The main idea is that instead of having a global
output/host and output/target in which all packages install files, we
switch to per-package host and target directories, that only contain
their explicit dependencies.

There are two main benefits:

 - Packages will now see only the dependencies they explicitly list in
   their <pkg>_DEPENDENCIES variable, and the recursive dependencies
   thereof.

 - We can support top-level parallel build properly, because a package
   only "sees" its own host directory and target directory, isolated
   from the build of other packages that can happen in parallel.

It works as follows:

 - A new output/per-package/ directory is created, which will contain
   one sub-directory per package, and inside it, a "host" directory
   and a "target" directory:

   output/per-package/busybox/target
   output/per-package/busybox/host
   output/per-package/host-fakeroot/target
   output/per-package/host-fakeroot/host

   This output/per-package/ directory is PER_PACKAGE_DIR.

 - The global TARGET_DIR and HOST_DIR variable now automatically point
   to the per-package directory when PKG is defined. So whenever a
   package references $(HOST_DIR) or $(TARGET_DIR) in its build
   process, it effectively references the per-package host/target
   directories. Note that STAGING_DIR is a sub-dir of HOST_DIR, so it
   is handled as well.

 - Of course, packages have dependencies, so those dependencies must
   be installed in the per-package host and target directories. To do
   so, we simply rsync (using hard links to save space and time) the
   host and target directories of the direct dependencies of the
   package to the current package host and target directories.

   We only need to take care of direct dependencies (and not
   recursively all dependencies), because we accumulate into those
   per-package host and target directories the files installed by the
   dependencies. Note that this only works because we make the
   assumption that one package does *not* overwrite files installed by
   another package.

   This is done for "extract dependencies" at the beginning of the
   extract step, and for "normal dependencies" at the beginning of the
   configure step.

This is basically enough to make per-package SDK and target work. The
only gotcha is that at the end of the build, output/target and
output/host are empty, which means that:

 - The filesystem image creation code cannot work.

 - We don't have a SDK to build code outside of Buildroot.

In order to fix this, this commit extends the target-finalize step so
that it starts by populating output/target and output/host by
rsync-ing into them the target and host directories of all packages
listed in the $(PACKAGES) variable. It is necessary to do this
sequentially in the target-finalize step and not in each
package. Doing it in package installation means that it can be done in
parallel. In that case, there is a chance that two rsyncs are creating
the same hardlink or directory at the same time, which makes one of
them fail.

This change to per-package directories has an impact on the RPATH
built into the host binaries, as those RPATH now point to various
per-package host directories, and no longer to the global host
directory. We do not try to rewrite such RPATHs during the build as
having such RPATHs is perfectly fine, but we still need to handle two
fallouts from this change:

 - The check-host-rpath script, which verifies at the end of each
   package installation that it has the appropriate RPATH, is modified
   to understand that a RPATH to $(PER_PACKAGE_DIR)/<pkg>/host/lib is
   a correct RPAT.

 - The fix-rpath script, which mungles the RPATH mainly for the SDK
   preparation, is modified to rewrite the RPATH to not point to
   per-package directories. Indeed the patchelf --make-rpath-relative
   call only works if the RPATH points to the ROOTDIR passed as
   argument, and this ROOTDIR is the global host directory. Rewriting
   the RPATH to not point to per-package host directories prior to
   this is an easy solution to this issue.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
2019-11-29 14:24:05 +01:00
Thomas Petazzoni
b1e294cc15 support/scripts/check-host-rpath: document existing functions
As suggested by Arnout Vandecappelle, let's document the
elf_needs_rpath() and check_elf_has_rpath() functions, before we make
them a bit more complicated with per-package directory support.

Suggested-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Reviewed-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
2019-01-17 22:38:34 +01:00
Thomas Petazzoni
eeb6341410 support/scripts/check-host-rpath: split condition on two statements
Inside the check_elf_has_rpath(), we check if the host binary has a
correct RPATH, which should be either an absolute path to
$(HOST_DIR)/lib, or a relative path using $ORIGIN. Those two
conditions are checked in a single statements, but as we are going to
add a third condition, let's split this up a bit:

 - If we have a RPATH to $(HOST_DIR)/lib -> we're good, return 0
 - If we have a RPATH to $ORIGIN/../lib -> we're good, return 0
 - Otherwise, we will exit the loop, and return 1

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Acked-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
2018-11-26 19:08:57 +01:00
Yann E. MORIN
c1cfee290e support/check-rpath: recognise PIE
We sanity-check the host executables that they have a correct RPATH
pointing to the host libraries.

This is currently done by looking for all files in $(HOST_DIR) that
match the 'ELF executable' pattern (a bit more complex, but that's
idea).

However, when an executable is built with -fPIE of -fpie, it no longer
appears to be an 'ELF executable', but it rather looks like an 'ELF
sheard object' (like if it were an library.

So, we miss those files.

It turns out that the problem is a real one, because quite a few
mainline distros, expecially those based on Debian for example, have
already switched to generating PIE code by default, and thus we miss on
a whole class of systems..

We fix that by simply looking if we can find an ELF interpreter in each
file. If we there is one, this is an ELF executable; if not, it may be
anything else: we don't care (not even about ELF libraries).

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Cc: Arnout Vandecappelle <arnout@mind.be>
Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
2017-09-27 00:13:55 +02:00
Arnout Vandecappelle
1d11d6314c check-host-rpath: no longer allow $(HOST_DIR)/usr
Now all packages have been updated to install things in $(HOST_DIR)/lib
instead of $(HOST_DIR)/usr/lib, there should no longer be any reason
to have $(HOST_DIR)/usr/lib in the RPATH, so we don't allow it any more.

Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
Cc: Wolfgang Grandegger <wg@grandegger.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
2017-07-05 16:54:12 +02:00
Arnout Vandecappelle
2295780a95 check-host-rpath: no longer check $(HOST_DIR)/usr/{bin, sbin}
Since $(HOST_DIR)/usr/{bin,sbin} are now symlinks to
$(HOST_DIR)/{bin,sbin}, it makes no sense to check them - they are
already covered.

Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
Reviewed-by: Romain Naour <romain.naour@smile.fr>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
2017-07-05 11:45:58 +02:00
Arnout Vandecappelle
4c790b8864 Move $(HOST_DIR)/usr/lib to $(HOST_DIR)/lib
This is a step towards eliminating $(HOST_DIR)/usr. It allows us to
convert all packages installing things into $(HOST_DIR)/usr/lib without
affecting the rest.

To allow compatibility with packages that still use $(HOST_DIR)/usr as
the prefix, create a symlink from usr/lib to ../lib.

Note that the symlink creation will break when $(HOST_DIR)/usr/lib
already exists as a directory, i.e. when rebuilding in an existing
output directory. This is necessary: if we don't break it now, the
following commits (which remove the usr part from various variables)
_will_ break it.

At the same time as creating this symlink, we also have to update the
check-host-rpath script to accept both $(HOST_DIR)/usr/lib and
$(HOST_DIR)/lib, because depending on how the package derives the
path, it may be different.

Since there are some dependency chains that involve $(STAGING_DIR),
$(STAGING_DIR) may in fact be created before $(HOST_DIR). Since
$(STAGING_DIR) is a subdirectory of $(HOST_DIR), it is possible that the
newly added rule for $(HOST_DIR) never triggers. To make sure that the
rule does trigger, add an order-only dependency from $(STAGING_DIR) to
$(HOST_DIR).

Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
Reviewed-by: Romain Naour <romain.naour@smile.fr>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
2017-07-05 11:39:58 +02:00
Wolfgang Grandegger
824f3d9beb support/scripts: check-host-rpath now handles $ORIGIN as well
"$ORIGIN/../../usr/lib" is also a valid RPATH for binaries in
"$hostdir/usr/bin". After RPATH sanitation, all RPATH
directories start with "$ORIGIN".

Signed-off-by: Wolfgang Grandegger <wg@grandegger.com>
Acked-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
Tested-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
2017-07-02 15:49:25 +02:00
Samuel Martin
bf8f0136e9 support/scripts/check-host-rpath: also check HOST_DIR/{bin, sbin}
At least syslinux is installing stuff in HOST_DIR/sbin.

Cc: "Yann E. MORIN" <yann.morin.1998@free.fr>
Signed-off-by: Samuel Martin <s.martin49@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
2016-04-21 22:17:36 +02:00
Yann E. MORIN
f42e262199 support/check-host-rpath: remove trailing '/' in host dir
Despite the comment saying so, the trailing '/' in the host directory is
not removed. Note however that it is properly removed from extracted
RPATH tags.

This is not visible when the host directory is our default $(O)/host
location, but breaks for user-supplied external host directory, when
the user leaves a trailing slash in the path.

Fix that.

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Cc: Peter Korsgaard <jacmet@uclibc.org>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
2015-12-02 23:28:14 +01:00
Yann E. MORIN
5c0c385226 core: check host executables have appropriate RPATH
When we build our host programs, and they depend on a host library we
also build, we want to ensure that program actually uses that library at
runtime, and not the one from the system.

We currently ensure that in two ways:
  - we add a RPATH tag that points to our host library directory,
  - we export LD_LIBRARY_PATH to point to that same directory.

With these two in place, we're pretty much confident that our host
libraries will be used by our host programs.

However, it turns our that not all the host programs we build end up
with an RPATH tag:
  - some packages do not use our $(HOST_LDFLAGS)
  - some packages' build system are oblivious to those LDFLAGS

In this case, there are two situations:
  - the program is not linked to one of our host libraries: it in fact
    does not need an RPATH tag [0]
  - the program actually uses one of our host libraries: in that case it
    should have had an RPATH tag pointing to the host directory.

For libraries, they only need an RPATH if they depend on another library
that is not installed in the standard library path. However, any system
library will already be in the standard library path, and any library we
install ourselves is in $(HOST_DIR)/usr/lib so already in RPATH.

We add a new support script that checks that all ELF executables have
a proper DT_RPATH (or DT_RUNPATH) tag when they link to our host
libraries, and reports those file that are missing an RPATH. If a file
missing an RPATH is an executable, the script aborts; if only libraries
are are missing an RPATH, the script does not abort.

[0] Except if it were to dlopen() it, of course, but the only program
I'm aware of that does that is openssl, and it has a correct RPATH tag.

[Peter: reworded as suggested by Arnout, fix HOT_DIR typo in comment]
Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: Arnout Vandecappelle <arnout@mind.be>
Cc: Peter Korsgaard <jacmet@uclibc.org>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
2015-11-18 22:47:10 +01:00