For Find modules where `<Modulename>` is not fully uppercase.
`<Modulename>` is case-exact name used in the Find modules filename:
`CMake/Find<Moduleame>.cmake`.
`find_package_handle_standard_args()` sets both `<MODULENAME>_FOUND` and
`<Modulename>_FOUND` when detecting the dependency. Some CMake code
relies on this and 3rd-party code may rely on it too. Make sure to set
the latter variant when detecting the dependency via `pkg-config`, where
we don't call `find_package_handle_standard_args()`.
CMake sets these variable to `TRUE` (not `ON` or `1`). Replicate this
for compatibility.
Closes#16153
Make the Find modules set and return their respective `pkg-config`
module name(s) to the CMake build process, which then adds those
to the `Requires:` list.
Before this patch, `pkg-config` module names were maintainted in two
separate places. After this patch, they are maintained in the Find
modules for dependencies that have one (most do).
Re-align existing modules with this change: msh3, mbedtls, rustls.
These modules return their `pkg-config` module name only when
detected via `pkg-config`.
Follow-up to d511ec8b0a#15573Closes#15800
Same issue as seen before with libssh2: `libpsl`'s pkg-config module
depends on another module, but that's not found. CMake ends up reporting
`LIBPSL_FOUND=YES`, while leaving `LIBPSL_INCLUDE_DIRS` empty. Then
the build fails to find `psl.h`.
The missing dependency in this case is `icu4c`, which is "keg-only",
meaning it's not exposed in the default Homebrew header, pkg-config,
lib, etc locations. It must be added to the `PKG_CONFIG_PATH` env, as
suggested by the warnings messages of `pkgconf`.
To avoid this fallout, let's ensure that `LIBPSL_INCLUDE_DIRS` is
non-empty when detecting via `pkg-config` and fall back to the CMake
detection method otherwise.
This was an issue till Homebrew libpsl 0.21.5_1, fixed in 0.21.5_2, that
no longer depends on `icu4c`.
Example log:
```
-- Checking for module 'libpsl'
-- Found libpsl, version 0.21.5
Package icu-uc was not found in the pkg-config search path.
Perhaps you should add the directory containing `icu-uc.pc'
to the PKG_CONFIG_PATH environment variable
Package 'icu-uc', required by 'libpsl', not found
[...]
-- Found Libpsl (via pkg-config): (found version "0.21.5")
[...]
In file included from curl/_bld/lib/CMakeFiles/libcurl_static.dir/Unity/unity_0_c.c:4:
In file included from curl/lib/altsvc.c:32:
In file included from curl/lib/urldata.h:145:
curl/lib/psl.h:28:10: fatal error: 'libpsl.h' file not found
^~~~~~~~~~
1 error generated.
```
Follow-up to 39c741b7b0#15408Closes#15827
brotli, c-ares, libpsl, libssh2, nghttp2, nghttp3, ntgcp2, zstd.
Also:
Add workaround for CMake reporting successful libssh2 detection, but
leaving the header directory empty, and causing `libssh2.h` not found
while compiling. It happens when `pkgconf` is not detecting libssh2
dependency libcrypto in Homebrew after `brew unlink openssl` (as in
GHA/macos). The workaround is to require a non-empty header directory
to consider the detection successful. This workaround may need to be
tweaked and/or applied to other Find modules.
Follow-up to 7bab201abe#15193Closes#15408
Extend `INSTALL-CMAKE` document with the list of available options,
a short description and default values.
The list may not be 100% complete.
There are no component boundaries in CMake, so the line is blurry
between curl options, CMake options, CMake Find modules options.
I included certain CMake options that seemed useful, and/or have
dedicated use withing curl's CMake source. But, all CMake built-in
options are usable, as documented upstream in CMake.
The naming of the options has a heritage and the inconsistencies with
it, including a lack of clear namespace. This may be subject to future
updates, also after figuring out which name has special meaning within
CMake and/or CMake projects out of unwritten convention or something
more tangible.
CMake allows to initialize any internal variable via `-D`. This may be
useful to pre-initialize/override feature check results. The list
doesn't contain these, and they remain officially undocumented.
Also:
- make adjustments to keep the spellchecker happy.
- retrofit description changes to the cmake sources.
- stop documenting deprecated `Find*` variables.
Reported-by: Daniel Stenberg
Fixes https://github.com/curl/curl/discussions/14885Closes#15388
- `FindCARES` -> `FindCares`
- `FindLibPSL` -> `FindLibpsl`
- `FindLibSSH2` -> `FindLibssh2`
- `FindQUICHE` -> `FindQuiche`
- `Findrustls` -> `FindRustls`
Our convention for naming Find modules (the part after the `Find`
prefix, also called as 'package name') is:
Always start with uppercase. Follow with lowercase, unless there is
a clear preference for a stylized name. E.g. the project itself uses it
that way with a matching `<Name>Config.cmake` file, or we use it that
way elsewhere, or the name is an acronym.
Ref: #14580Closes#14601