curl-curl/CMake/FindZstd.cmake
Viktor Szakats 8fce3e17e6
cmake: add CMake Config-based dependency detection
After limiting `find_package()`/`find_dependency()` calls to curl local
Find modules via the `MODULES` keyword, it became possible to detect
dependencies via CMake Configs from within those local Find modules, by
calling `find_package()` again with the `CONFIG` keyword. This patch
implements this. Then maps detection results to the result variables and
curl-specific imported targets the rest of the build expects.

Also honor recently introduced `*_USE_STATIC_LIBS` (experimental) flags
to map to the static target when requested.

This adds CMake Configs as an alternative to the existing `pkg-config`
and `find_path()`/`find_library()` auto-detection methods.

Enabled by default for MSVC, outside vcpkg and when not cross-building.
To enable for other cases, or override the default, you can use
`-DCURL_USE_CMAKECONFIG=ON` or `OFF`.

When enabled, Config detection happens after `pkg-config` and before
`find_path()`/`find_library()`. Using CMake's built-in options, you may
also manually point to the absolute directory holding Config files:

`Libssh2_DIR`, `MbedTLS_DIR`, `NGHTTP2_DIR`, `NGHTTP3_DIR`,
`NGTCP2_DIR` v1.19.0+ (with non-fork OpenSSL only), `Zstd_DIR` v1.4.5+

E.g. `-DMbedTLS_DIR=/path/to/mbedtls/lib/cmake/MbedTLS`

These dependencies typically need to be built with CMake to support
this.

Tagged as experimental.

Refs:
#20013 #19156 #19117
https://github.com/curl/curl/pull/20784#issuecomment-3984318492

Depends-on: fad1ebaecc #20840
Follow-up to 91e06fde1b #20784
Follow-up to 26c39d8df1 #20015

Closes #20814
2026-03-21 18:52:31 +01:00

144 lines
5.1 KiB
CMake

#***************************************************************************
# _ _ ____ _
# Project ___| | | | _ \| |
# / __| | | | |_) | |
# | (__| |_| | _ <| |___
# \___|\___/|_| \_\_____|
#
# Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
#
# This software is licensed as described in the file COPYING, which
# you should have received as part of this distribution. The terms
# are also available at https://curl.se/docs/copyright.html.
#
# You may opt to use, copy, modify, merge, publish, distribute and/or sell
# copies of the Software, and permit persons to whom the Software is
# furnished to do so, under the terms of the COPYING file.
#
# This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
# KIND, either express or implied.
#
# SPDX-License-Identifier: curl
#
###########################################################################
# Find the zstd library
#
# Input variables:
#
# - `ZSTD_INCLUDE_DIR`: Absolute path to zstd include directory.
# - `ZSTD_LIBRARY`: Absolute path to `zstd` library.
# - `ZSTD_USE_STATIC_LIBS`: Configure for static zstd libraries.
#
# Defines:
#
# - `ZSTD_FOUND`: System has zstd.
# - `ZSTD_VERSION`: Version of zstd.
# - `CURL::zstd`: zstd library target.
if(DEFINED Zstd_INCLUDE_DIR AND NOT DEFINED ZSTD_INCLUDE_DIR)
message(WARNING "Zstd_INCLUDE_DIR is deprecated, use ZSTD_INCLUDE_DIR instead.")
set(ZSTD_INCLUDE_DIR "${Zstd_INCLUDE_DIR}")
endif()
if(DEFINED Zstd_LIBRARY AND NOT DEFINED ZSTD_LIBRARY)
message(WARNING "Zstd_LIBRARY is deprecated, use ZSTD_LIBRARY instead.")
set(ZSTD_LIBRARY "${Zstd_LIBRARY}")
endif()
set(_zstd_pc_requires "libzstd")
if(NOT DEFINED ZSTD_INCLUDE_DIR AND
NOT DEFINED ZSTD_LIBRARY)
if(CURL_USE_PKGCONFIG)
find_package(PkgConfig QUIET)
pkg_check_modules(_zstd ${_zstd_pc_requires})
endif()
if(NOT _zstd_FOUND AND CURL_USE_CMAKECONFIG)
find_package(Zstd CONFIG QUIET)
# Skip using if older than v1.4.5
if(Zstd_CONFIG AND
NOT TARGET zstd::libzstd_static AND
NOT TARGET zstd::libzstd_shared)
unset(Zstd_CONFIG)
endif()
endif()
endif()
if(_zstd_FOUND)
set(Zstd_FOUND TRUE)
set(ZSTD_FOUND TRUE)
set(ZSTD_VERSION ${_zstd_VERSION})
if(ZSTD_USE_STATIC_LIBS)
set(_zstd_CFLAGS "${_zstd_STATIC_CFLAGS}")
set(_zstd_INCLUDE_DIRS "${_zstd_STATIC_INCLUDE_DIRS}")
set(_zstd_LIBRARY_DIRS "${_zstd_STATIC_LIBRARY_DIRS}")
set(_zstd_LIBRARIES "${_zstd_STATIC_LIBRARIES}")
endif()
message(STATUS "Found Zstd (via pkg-config): ${_zstd_INCLUDE_DIRS} (found version \"${ZSTD_VERSION}\")")
elseif(Zstd_CONFIG)
set(ZSTD_FOUND TRUE)
set(ZSTD_VERSION ${Zstd_VERSION})
if(ZSTD_USE_STATIC_LIBS)
set(_zstd_LIBRARIES zstd::libzstd_static)
elseif(TARGET zstd::libzstd)
set(_zstd_LIBRARIES zstd::libzstd) # v1.5.6+
else()
set(_zstd_LIBRARIES zstd::libzstd_shared)
endif()
message(STATUS "Found Zstd (via CMake Config): ${Zstd_CONFIG} (found version \"${ZSTD_VERSION}\")")
else()
find_path(ZSTD_INCLUDE_DIR NAMES "zstd.h")
if(ZSTD_USE_STATIC_LIBS)
find_library(ZSTD_LIBRARY NAMES "zstd_static" "zstd")
else()
find_library(ZSTD_LIBRARY NAMES "zstd")
endif()
unset(ZSTD_VERSION CACHE)
if(ZSTD_INCLUDE_DIR AND EXISTS "${ZSTD_INCLUDE_DIR}/zstd.h")
set(_version_regex1 "#[\t ]*define[ \t]+ZSTD_VERSION_MAJOR[ \t]+([0-9]+).*")
set(_version_regex2 "#[\t ]*define[ \t]+ZSTD_VERSION_MINOR[ \t]+([0-9]+).*")
set(_version_regex3 "#[\t ]*define[ \t]+ZSTD_VERSION_RELEASE[ \t]+([0-9]+).*")
file(STRINGS "${ZSTD_INCLUDE_DIR}/zstd.h" _version_str1 REGEX "${_version_regex1}")
file(STRINGS "${ZSTD_INCLUDE_DIR}/zstd.h" _version_str2 REGEX "${_version_regex2}")
file(STRINGS "${ZSTD_INCLUDE_DIR}/zstd.h" _version_str3 REGEX "${_version_regex3}")
string(REGEX REPLACE "${_version_regex1}" "\\1" _version_str1 "${_version_str1}")
string(REGEX REPLACE "${_version_regex2}" "\\1" _version_str2 "${_version_str2}")
string(REGEX REPLACE "${_version_regex3}" "\\1" _version_str3 "${_version_str3}")
set(ZSTD_VERSION "${_version_str1}.${_version_str2}.${_version_str3}")
unset(_version_regex1)
unset(_version_regex2)
unset(_version_regex3)
unset(_version_str1)
unset(_version_str2)
unset(_version_str3)
endif()
include(FindPackageHandleStandardArgs)
find_package_handle_standard_args(Zstd
REQUIRED_VARS
ZSTD_INCLUDE_DIR
ZSTD_LIBRARY
VERSION_VAR
ZSTD_VERSION
)
if(ZSTD_FOUND)
set(_zstd_INCLUDE_DIRS ${ZSTD_INCLUDE_DIR})
set(_zstd_LIBRARIES ${ZSTD_LIBRARY})
endif()
mark_as_advanced(ZSTD_INCLUDE_DIR ZSTD_LIBRARY)
endif()
if(ZSTD_FOUND)
if(NOT TARGET CURL::zstd)
add_library(CURL::zstd INTERFACE IMPORTED)
set_target_properties(CURL::zstd PROPERTIES
INTERFACE_LIBCURL_PC_MODULES "${_zstd_pc_requires}"
INTERFACE_COMPILE_OPTIONS "${_zstd_CFLAGS}"
INTERFACE_INCLUDE_DIRECTORIES "${_zstd_INCLUDE_DIRS}"
INTERFACE_LINK_DIRECTORIES "${_zstd_LIBRARY_DIRS}"
INTERFACE_LINK_LIBRARIES "${_zstd_LIBRARIES}")
endif()
endif()