This resolves a conflict between the RPM generated by the libjpeg-turbo
build system and the Red Hat 'filesystem' RPM if
CMAKE_INSTALL_LIBDIR=/usr/lib[64]. This code was largely borrowed from
the VirtualGL RPM spec. (I can legally do that because I hold the
copyright on VirtualGL's implementation.)
Fixes#532
The previous AArch64 GAS implementation has been removed, since the
intrinsics implementation provides the same or better performance.
There was no previous AArch32 GAS implementation.
The checkstyle script was hastily developed prior to libjpeg-turbo 2.0
beta1, so it has a lot of exceptions and is thus prone to false
negatives. This commit eliminates some of those exceptions.
- Don't enumerate the types of SIMD instructions that libjpeg-turbo
supports, as this can change without notice.
- Use more clear terminology when describing support for libjpeg v7/v8
features ("libjpeg" is, colloquially but not officially, the name for
the IJG's software, whereas the "libjpeg API" refers to our emulation
of said software.)
- "PhotoShop" = "Photoshop" (StudLy Caps Police)
- Adjust dynamic library versions to reflect the addition of
jpeg_read_icc_profile() and jpeg_write_icc_profile() in
libjpeg-turbo 2.0.x.
%{_libdir}/pkgconfig is a directory and should thus be prefixed by
%{dir} (oops.) This issue caused the debuginfo build under RHEL 8
(which is apparently now enabled by default-- regardless of whether the
RPM actually contains debug info, but that's another matter) to fail
with:
RPM build errors:
File listed twice: /opt/libjpeg-turbo/lib64/pkgconfig/libjpeg.pc
File listed twice: /opt/libjpeg-turbo/lib64/pkgconfig/libturbojpeg.pc
On RHEL 7 and later (not sure exactly whether this is a product of the
newer RPM release or something distro-specific), macros are lazily
expanded, so we need to set _docdir using %global (which expands at
definition time) and prior to _prefix and _datarootdir (which affect
_defaultdocdir.) Otherwise, _docdir is set to a subdirectory of
/opt/libjpeg-turbo/share/doc or /opt/libjpeg-turbo/doc. The former
(which happens on RHEL 7) leads to incorrect documentation packaging
(the docs should be packaged under /usr/share/doc per Red Hat
standards), and the latter (which happens on RHEL 8) leads to an RPM
build error.
AFAICT, Requires and BuildRequires subsumed the functionality of Prereq
and BuildPrereq in RPM 4.0, and none of the platforms we support with
libjpeg-turbo 2.0.x has RPM < 4.4.
Setting _libdir to CMAKE_INSTALL_FULL_LIBDIR only works when doing an
in-tree RPM build. SRPMs are architecture-agnostic, so the spec needs
to compute_libdir at the time the SRPM is rebuilt, not at the time it
is generated.
This is a regression introduced when implementing the new CMake-based
cross-platform build system.
- GNUInstallDirs: any directory variable can now reference any other
directory variable by including its name in angle brackets (<>).
- Changed the documentation of the directory variables in BUILDING.md
accordingly. This commit also includes some formatting tweaks to
that section (using boldface for directory names, as is our
convention.)
- Changed the package scripts such that they use
CMAKE_INSTALL_DATAROOTDIR rather than CMAKE_INSTALL_DATADIR.
- We no longer override the install dir. defaults on Windows unless
performing an official build. It may be useful, for instance, to
use the GNU defaults when installing into an MSYS environment.
This builds upon the existing GNUInstallDirs module in CMake but adds
the following features to that module:
- The ability to override the defaults for each install directory
through a new set of variables (`CMAKE_INSTALL_DEFAULT_*DIR`).
Before operating system vendors began shipping libjpeg-turbo, it was
meant to be a run-time drop-in replacement for the system's
distribution of libjpeg, so it has traditionally installed itself
under /opt/libjpeg-turbo on Un*x systems by default. On Windows, it
has traditionally installed itself under %SystemDrive%\libjpeg-turbo*,
which is not uncommon behavior for open source libraries (open source
SDKs tend to install outside of the Program Files directory so as to
avoid spaces in the directory name.) At least in the case of Un*x,
the install directory behavior is based somewhat on the Solaris
standard, which requires all non-O/S packages to install their files
under /opt/{package_name}. I adopted that standard for VirtualGL and
TurboVNC while working at Sun, because it allowed those packages to be
located under the same directory on all platforms. I adopted it for
libjpeg-turbo because it ensured that our files would never conflict
with the system's version of libjpeg. Even though many Un*x
distributions ship libjpeg-turbo these days, not all of them ship the
TurboJPEG API library or the Java classes or even the latest version
of the libjpeg API library, so there are still many cases in which it
is desirable to install a separate version of libjpeg-turbo than the
one installed by the system. Furthermore, installing the files under
/opt mimics the directory structure of our official binary packages,
and it makes it very easy to uninstall libjpeg-turbo.
For these reasons, our build system needs to be able to use
non-GNU-compliant defaults for each install directory if
`CMAKE_INSTALL_PREFIX` is set to the default value.
- For each directory variable, the module now detects changes to
`CMAKE_INSTALL_PREFIX` and changes the directory variable accordingly,
if the variable has not been changed by the user.
This makes it easy to switch between our "official" directory
structure and the GNU-compliant directory structure "on the fly"
simply by changing `CMAKE_INSTALL_PREFIX`. Also, this new mechanism
eliminated the need for the crufty mechanism that previously did the
same thing just for the library directory variable.
How it should work:
- If a dir variable is unset, then the module will set an internal
property indicating that the dir variable was initialized to its
default value.
- If the dir variable ever diverges from its default value, then the
internal property is cleared, and it cannot be set again without
unsetting the dir variable.
- If the install prefix changes, and if the internal property
indicates that the dir variable is still set to its default value,
and if the dir variable's value is not being manually changed at the
same time that the install prefix is being changed, then the dir
variable's value is automatically changed to the new default value
for that variable (as determined by the new install prefix.)
- The directory variables are now always cached, regardless of whether
they were set on the command line or not. This ensures that they can
easily be examined and modified after being set, regardless of how they
were set.
This was made possible by the introduction of the aforementioned
`CMAKE_INSTALL_DEFAULT_*DIR` variables.
- Improved directory variable documentation (based on descriptions at
https://www.gnu.org/prep/standards/html_node/Directory-Variables.html)
- The module now allows "<DATAROOTDIR>" to be used as a placeholder in
relative directory variables.
It is replaced "on the fly" with the actual path of
`CMAKE_INSTALL_DATAROOTDIR`.
This should more closely mimic the behavior of the old autotools build
system while retaining our customizations to it, and it should retain
the behavior of the old CMake build system.
Closes#124
- Replace CMAKE_SOURCE_DIR with CMAKE_CURRENT_SOURCE_DIR
- Replace CMAKE_BINARY_DIR with CMAKE_CURRENT_BINARY_DIR
- Don't use "libjpeg-turbo" in any of the package system filenames
(because CMAKE_PROJECT_NAME will not be the same if building LJT as
a submodule.)
Closes#122
