Require CMake 3.18 (2020-07-15) or newer, up from 3.7 (2016-11-11)
prior to this patch.
This requirement also applies to the distributed `curl-config.cmake`.
To allow dropping compatibility code maintained for old versions, and to
use features which were unpractical in separate code paths. Also to make
testing, documentation and development easier, CI builds faster due to
CMake performance improvements over time. (e.g. integration tests on
macOS run 8x faster (10 minutes is now under 1.5m) in CI, 2.5x faster on
Windows.)
CMake offers pre-built binaries for major platforms. They work without
an install step, just by unpacking and pointing the cmake command to
them. Making upgrades easy in many cases:
https://cmake.org/download/https://cmake.org/files/https://github.com/Kitware/CMake/releases
CMake 3.18 brings these feature as generally available when building or
consuming curl/libcurl:
LTO support, improved performance, `pkg-config` and interface target
support, `OBJECT` target (for faster libcurl builds), modern invocation
with `-S`/`-B` options, better support for custom linker options,
FetchContent, `GnuTLS::GnuTLS` target, `--verbose` and `--install`
options, `CMAKE_GENERATOR` env, last but not least unity mode and Ninja
generator.
For maximum build speed, use:
`-DCMAKE_UNITY_BUILD=ON -DCURL_DROP_UNUSED=ON`
As for deprecations, C++11 is required to build CMake itself, which may
be a limit on some platforms. autotools continues to cover them.
Follow-up to 9bcdfb3809#20408
Follow-up to a7c974e038#19902
Follow-up to dfbe035c8b#10161
Discussion: https://github.com/curl/curl/discussions/18704Closes#20407
Via options:
- `BROTLI_USE_STATIC_LIBS`
- `CARES_USE_STATIC_LIBS`
- `LIBSSH_USE_STATIC_LIBS`
- `LIBSSH2_USE_STATIC_LIBS`
- `MBEDTLS_USE_STATIC_LIBS`
- `NGHTTP2_USE_STATIC_LIBS`
- `NGHTTP3_USE_STATIC_LIBS`
- `NGTCP2_USE_STATIC_LIBS`
- `ZSTD_USE_STATIC_LIBS`
When enabled, make a "best effort" finding static libs first and set
the "build static" macro (on Windows) as required by the dependency.
When doing `pkg-config`-based detections, make curl select the static
configuration, which shall set the "build static" macro also.
These options resemble CMake's `OPENSSL_USE_STATIC_LIBS` and
`ZLIB_USE_STATIC_LIBS` (the latter does not support `pkg-config` as of
CMake v4.2.2).
Shared/static library selection based on loose filename conventions is
fragile and prone to break if the non-static-suffixed library is found
and happens to be a shared library, or, if the linker decides to pick up
a shared copy (e.g. `.a.dll`) that shadows the static one. It may help
to provide either static or shared, but not both, on the disk, and match
that with this setting.
Experimental.
Ref: #20013Closes#20015
Rework the way curl's custom Find modules advertise their properties.
Before this patch, Find modules returned detected dependency properties
(header dirs, libs, libdirs, C flags, etc.) via global variables. curl's
main `CMakeLists.txt` copied their values into global lists, which it
later applied to targets. This solution worked internally, but it was
unsuited for the public, distributed `CURLConfig.cmake` and publishing
curl's Find modules with it, due to polluting the namespace of consumer
projects. It's also impractical to apply the many individual variables
to every targets depending on libcurl.
To allow using Find modules in consumer projects, this patch makes them
define as imported interface targets, named `CURL::<dependency>`. Then
store dependency information as target properties. It avoids namespace
pollution and makes the dependency information apply automatically
to all targets using `CURL::libcurl_static`.
Find modules continue to return `*_FOUND` and `*_VERSION` variables.
For dependencies detected via `pkg-config`, CMake 3.16+ is recommended.
Older CMake versions have a varying degree of support for
propagating/handling library directories. This may cause issues in envs
where dependencies reside in non-system locations and detected via
`pkg-config` (e.g. macOS + Homebrew). Use `CURL_USE_PKGCONFIG=OFF`
to fix these issues. Or upgrade to newer CMake, or link libcurl
dynamically.
Also:
- re-enable `pkg-config` for old cmake `find_library()` integration
tests.
- make `curlinfo` build after these changes.
- distribute local Find modules.
- export the raw list of lib dependencies via `CURL_LIBRARIES_PRIVATE`.
- `CURLconfig.cmake`: use curl's Find modules to detect dependencies in
the consumer env.
- add custom property to target property debug function.
- the curl build process no longer modifies `CMAKE_C_FLAGS`.
Follow-up to e86542038d#17047
Ref: #14930
Ref: https://github.com/libssh2/libssh2/pull/1535
Ref: https://github.com/libssh2/libssh2/pull/1571
Ref: https://github.com/libssh2/libssh2/pull/1581
Ref: https://github.com/libssh2/libssh2/pull/1623Closes#16973
To not have to guess. Also to sync with autotools, which already uses
this wording.
Also:
- replace the stray term 'folder' with 'directory' for consistency.
- store help text in a temp variable to avoid overly long strings
(mandatory in CMake <4.2.0 and can't be trivially split), also
to avoid repeating this string 4 times.
Ref: https://cmake.org/cmake/help/v4.2/command/set.htmlCloses#19169
It broke cmake builds with OpenSSL 3.5.0 and ngtcp2 1.12.0 or newer,
when detected via `pkg-config`.
For brotli, mbedtls, LDAP, ngtcp2 builds, it caused their version
numbers missing from the configure log when detected via `pkg-config`.
Regression from 01e45f81bd#16980
Regression from 3b501976a9#16479
Bug: https://github.com/curl/curl/pull/16980#issuecomment-2916811388
Reported-by: x-xiang on github
Closes#17476
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
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
It allows finding the ngtcp2 crypto interface library automatically when
using a custom `NGTCP2_LIBRARY`.
Before this patch the library location had to be added via
`CMAKE_LIBRARY_PATH` or by other means.
Also add empty lines for readability / uniformity.
Fixes 8b8909e120/curl.sh (L289)Closes#14905
- add `NAMES` where missing.
- document input variables (including deprecated ones.)
- comment cleanups.
- FindWolfSSL: drop stray `QUIET` from `pkg_check_modules()`.
(`QUIET` may be re-added for all modules in the future.)
Closes#14579
- fix to add the `m` library without path.
Follow-up to 8577f4ca08#14343
Authored-by: Tal Regev
Fixes#14549
- move `m` library detection to wolfSSL Find module.
`m` is necessary for wolfSSL (wolfcrypt) library functions called by
`libngtcp2_crypto_wolfssl`.
Follow-up to 8577f4ca08#14343
- fix comment header about supported `COMPONENT` names.
- quote strings.
- lowercase local variables.
Closes#14576
- move variable dump to a GHA foldable group.
- minimize scope for an include().
- rename `HIDES_CURL_PRIVATE_SYMBOLS` to `CURL_HIDES_PRIVATE_SYMBOLS`,
to keep it in the curl namespace.
- drop quotes from a version number.
- add missing `Makefile.inc` var refs to comment.
- FindNGTCP2: rename internal var to underscore/lowercase.
- FindBearSSL, FindGSS: whitespace.
Closes#14571
Prefer `pkg_check_modules()` over `pkg_search_module()`.
`pkg_check_modules()` logs a line when there is a hit, and also warnings
if a sub-dependency is missing. In `QUIET` mode, both are silent.
The extra info is useful to see if a detection happened via
`pkg-config`.
Keep `pkg_search_module()` in `FindGSS`. We pass two dependencies
there and we want to keep stopping on the first one.
Partially reverts c2889a7b41#14388Closes#14573
- use `pkg-config` version when available and where it wasn't yet used.
- add manual version detection for dependencies where this is possible
(via a public header) and where it wasn't done yet.
Closes#14548
Smoothen out minor differences between Find modules.
- brotli, nghttp2: drop redundant `FOUND_VAR` specifiers from
`find_package_handle_standard_args()` calls.
This function sets both `<NAME_UPPER>_FOUND` and `<NAME>_FOUND`
by default.
- brotli: set result vars only when found.
- brotli: add missing `mark_as_advanced()` call.
- brotli: delete custom fail message.
- mbedtls, bearssl: use `REQUIRED_VARS` instead of `DEFAULT_MSG`.
- msh3, quiche: set `<NAME>_VERSION` (via pkg-config).
- wolfssl: also use `PC_WOLFSSL_INCLUDEDIR`, `PC_WOLFSSL_LIBDIR`
as hints.
- libpsl, libssh2, zstd: clear temporary variables used for version
detection.
- gss, msh3, nghttp2, nghttp3, ngtcp2, quiche, zstd: fix to apply
`mark_as_advanced()` to internal variables only.
Closes#14538
Add option to control whether to use `pkg-config` to detect
dependencies. Curl's CMake uses `pkg-config` by default for all targets
except for MSVC without vcpkg.
With the CMake option `-DCURL_USE_PKGCONFIG=ON` you can override it to
use `pkg-config` always.
If `pkg-config` is causing issues, e.g. in cross-builds or other cases,
`-DCURL_USE_PKGCONFIG=OFF` disables all use of `pkg-config`.
Also add it to `curl-config.cmake`. Not yet used, but will be once curl
starts referencing any curl-specific `Find*` module from this public
script.
Follow-up to 9dfdc6ff42#14483Closes#14504
Before this patch, `pkg-config` was used for `UNIX` builds only (with
a few exceptions like wolfSSL, libssh, gsasl, libuv). This patch extends
`pkg-config` use to all envs except: `MSVC` without vcpkg. Meaning MSVC
with vcpkg will now use it. Also mingw on Windows.
Also apply the new condition to options where `pkg-config` was used
unconditionally (= for all targets). These are:
`-DCURL_USE_WOLFSSL=ON`, `-DCURL_USE_LIBSSH=ON`,
`-DCURL_USE_GSASL=ON` and `-DCURL_USE_LIBUV=ON`
This patch may still cause regressions for cross-builds (e.g. mingw
cross-build from Unix) and potentially other cases. If that happens, we
recommend using some of these methods to explicitly disable `pkg-config`
when using CMake:
- CMake option: `-DPKG_CONFIG_EXECUTABLE=`
(or `-DPKG_CONFIG_EXECUTABLE=nonexistent` or similar)
This is similar to the (curl-specific) `PKG_CONFIG` env for autotools.
- export env: `PKG_CONFIG_LIBDIR=`
(or `PKG_CONFIG_PATH`, `PKG_CONFIG_SYSROOT_DIR`,
or the CMake-specific `PKG_CONFIG`)
We may improve control over this in a future patch, also allowing opting
in MSVC (without vcpkg).
Ref: #14405
Ref: #14408
Ref: #14140Closes#14483
- quote string literals.
In the hope it improves syntax-highlighting and readability.
- use lowercase, underscore-prefixed local var names.
As a hint for scope, to help readability.
- prefer `pkg_search_module` (over `pkg_check_modules`).
They are the same, but `pkg_search_module` stops searching
at the first hit.
- more `IN LISTS` in `foreach()`.
- OtherTests.cmake: clear `CMAKE_EXTRA_INCLUDE_FILES` after use.
- add `PROJECT_LABEL` for http/client and unit test targets.
- sync `Find*` module comments and formatting.
- drop a few local variables.
- drop bogus `CARES_LIBRARIES` from comment.
- unquote numeric literal.
Follow-up to acbc6b703f#14197Closes#14388
- tidy-up comments.
- use lowercase, underscore prefixed names for internal variables.
- use `IN LISTS` and `IN ITEMS` in `foreach()` loops.
- rename variable name `OUTPUT` to a more distinctive one.
- tidy-up `STREQUAL` syntax.
- delete commented code.
- indent/whitespace.
Closes#14197
- add QUIC/ngtcp2 detection in CMake with wolfSSL.
Because wolfSSL uses zlib if available, move compression detection
before TLS detection. (OpenSSL might also need this in the future.)
- wolfSSL 5.5.0 started using C99 types in its `quic.h` header, but it
doesn't #include the necessary C99 header itself, breaking builds
(unless another dependency pulled it by chance.) Add local workaround
for it. For this to work with all build tools, we had to fix our
header detection first. Ref: #10745
Ref: 6ad5f6ecc1Closes#10739
- they are mostly pointless in all major jurisdictions
- many big corporations and projects already don't use them
- saves us from pointless churn
- git keeps history for us
- the year range is kept in COPYING
checksrc is updated to allow non-year using copyright statements
Closes#10205
Update the ngtcp2 find module to detect the boringssl backend. Determine
if the underlying OpenSSL implementation is BoringSSL and if so use that
as the ngtcp2 backend.
Reviewed-by: Jakub Zakrzewski
Closes#9065
Add licensing and copyright information for all files in this repository. This
either happens in the file itself as a comment header or in the file
`.reuse/dep5`.
This commit also adds a Github workflow to check pull requests and adapts
copyright.pl to the changes.
Closes#8869
Add three new CMake Find modules (using the curl license, but I grant
others the right to apply the CMake BSD license instead).
This CMake config is simpler than the autotools one because it assumes
ngtcp2 and nghttp3 to be used together. Another difference is that this
CMake config checks whether QUIC is actually supported by the TLS
library (patched OpenSSL or boringssl) since this can be a common
configuration mistake that could result in build errors later.
Unlike autotools, CMake does not warn you that the features are
experimental. The user is supposed to already know that and read the
documentation. It requires a very special build environment anyway.
Tested with ngtcp2+OpenSSL+nghttp3 and quiche+boringssl, both built from
current git master. Use `LD_DEBUG=files src/curl |& grep need` to figure
out which features (libldap-2.4, libssh2) to disable due to conflicts
with boringssl.
Closes#5359
