pkgconfig: add support to override pkg-config

mesonbuild/dependencies/pkgconfig.py

@@ -6,7 +6,16 @@
 from pathlib import Path
 
 from .base import ExternalDependency, DependencyException, sort_libpaths, DependencyTypeName
-from ..mesonlib import EnvironmentVariables, OrderedSet, PerMachine, Popen_safe, Popen_safe_logged, MachineChoice, join_args
+from ..mesonlib import (
+    EnvironmentVariables,
+    OrderedSet,
+    PerMachine,
+    Popen_safe,
+    Popen_safe_logged,
+    MachineChoice,
+    join_args,
+    MesonException,
+)
 from ..options import OptionKey
 from ..programs import find_external_program, ExternalProgram
 from .. import mlog
@@ -30,14 +39,24 @@ class PkgConfigInterface:
 
     class_impl: PerMachine[T.Union[Literal[False], T.Optional[PkgConfigInterface]]] = PerMachine(False, False)
     class_cli_impl: PerMachine[T.Union[Literal[False], T.Optional[PkgConfigCLI]]] = PerMachine(False, False)
+    pkg_bin_per_machine: PerMachine[T.Union[Literal[False], T.Optional[ExternalProgram]]] = PerMachine(False, False)
+
+    @staticmethod
+    def set_program_override(pkg_bin: ExternalProgram, for_machine: MachineChoice) -> None:
+        if PkgConfigInterface.class_impl[for_machine]:
+            raise MesonException(
+                f"Tried to override pkg-config for machine {for_machine} but it was already initialized.\n"
+                "pkg-config must be overridden before it's used."
+            )
+        PkgConfigInterface.pkg_bin_per_machine[for_machine] = pkg_bin
 
     @staticmethod
     def instance(env: Environment, for_machine: MachineChoice, silent: bool) -> T.Optional[PkgConfigInterface]:
         '''Return a pkg-config implementation singleton'''
         for_machine = for_machine if env.is_cross_build() else MachineChoice.HOST
         impl = PkgConfigInterface.class_impl[for_machine]
         if impl is False:
-            impl = PkgConfigCLI(env, for_machine, silent)
+            impl = PkgConfigCLI(env, for_machine, silent, PkgConfigInterface.pkg_bin_per_machine[for_machine])
             if not impl.found():
                 impl = None
             if not impl and not silent:
@@ -57,7 +76,7 @@ def _cli(env: Environment, for_machine: MachineChoice, silent: bool = False) ->
         if impl and not isinstance(impl, PkgConfigCLI):
             impl = PkgConfigInterface.class_cli_impl[for_machine]
             if impl is False:
-                impl = PkgConfigCLI(env, for_machine, silent)
+                impl = PkgConfigCLI(env, for_machine, silent, PkgConfigInterface.pkg_bin_per_machine[for_machine])
                 if not impl.found():
                     impl = None
                 PkgConfigInterface.class_cli_impl[for_machine] = impl
@@ -113,9 +132,11 @@ def list_all(self) -> ImmutableListProtocol[str]:
 class PkgConfigCLI(PkgConfigInterface):
     '''pkg-config CLI implementation'''
 
-    def __init__(self, env: Environment, for_machine: MachineChoice, silent: bool) -> None:
+    def __init__(
+        self, env: Environment, for_machine: MachineChoice, silent: bool, pkgbin: T.Optional[ExternalProgram] = None
+    ) -> None:
         super().__init__(env, for_machine)
-        self._detect_pkgbin()
+        self._detect_pkgbin(pkgbin)
         if self.pkgbin and not silent:
             mlog.log('Found pkg-config:', mlog.green('YES'), mlog.bold(f'({self.pkgbin.get_path()})'), mlog.blue(self.pkgbin_version))
 
@@ -200,14 +221,27 @@ def _split_args(cmd: str) -> T.List[str]:
         # output using shlex.split rather than mesonlib.split_args
         return shlex.split(cmd)
 
-    def _detect_pkgbin(self) -> None:
-        for potential_pkgbin in find_external_program(
-                self.env, self.for_machine, 'pkg-config', 'Pkg-config',
-                self.env.default_pkgconfig, allow_default_for_cross=False):
+    def _detect_pkgbin(self, pkgbin: T.Optional[ExternalProgram] = None) -> None:
+        def validate(potential_pkgbin: ExternalProgram) -> bool:
             version_if_ok = self._check_pkgconfig(potential_pkgbin)
             if version_if_ok:
                 self.pkgbin = potential_pkgbin
                 self.pkgbin_version = version_if_ok
+                return True
+            return False
+
+        if pkgbin and validate(pkgbin):
+            return
+
+        for potential_pkgbin in find_external_program(
+            self.env,
+            self.for_machine,
+            "pkg-config",
+            "Pkg-config",
+            self.env.default_pkgconfig,
+            allow_default_for_cross=False,
+        ):
+            if validate(potential_pkgbin):
                 return
         self.pkgbin = None
 

mesonbuild/interpreter/interpreter.py

@@ -23,7 +23,7 @@
                         extract_as_list, has_path_sep, path_is_in_root, PerMachine)
 from ..options import OptionKey
 from ..programs import ExternalProgram, NonExistingExternalProgram
-from ..dependencies import Dependency
+from ..dependencies import Dependency, pkgconfig
 from ..depfile import DepFile
 from ..interpreterbase import ContainerTypeInfo, InterpreterBase, KwargInfo, typed_kwargs, typed_pos_args
 from ..interpreterbase import noPosargs, noKwargs, permittedKwargs, noArgsFlattening, noSecondLevelHolderResolving, unholder_return
@@ -1638,6 +1638,8 @@ def add_find_program_override(self, name: str, exe: T.Union[build.Executable, Ex
         if name in self.build.find_overrides:
             raise InterpreterException(f'Tried to override executable "{name}" which has already been overridden.')
         self.build.find_overrides[name] = exe
+        if name == "pkg-config" and exe is ExternalProgram:
+            pkgconfig.PkgConfigInterface.set_program_override(exe, MachineChoice.HOST)
 
     def notfound_program(self, args: T.List[mesonlib.FileOrString]) -> ExternalProgram:
         return NonExistingExternalProgram(' '.join(

test cases/common/279 pkgconfig override/meson.build

@@ -0,0 +1,8 @@
+project('override pkg-config', 'c')
+
+subproject('pkg-config')
+
+pkgconfig = find_program('pkg-config')
+
+# This dependency can only be found if pkg-config is overridden with our custom pkg-config.py
+gobj = dependency('test-package-0.0', version : '= 0.0.0')

test cases/common/279 pkgconfig override/subprojects/pkg-config.wrap

@@ -0,0 +1,5 @@
+[wrap-file]
+directory = pkg-config
+
+[provide]
+program_names = pkg-config

test cases/common/279 pkgconfig override/subprojects/pkg-config/bin/pkg-config.py

@@ -0,0 +1,13 @@
+#!/usr/bin/env python3
+
+import sys
+
+if len(sys.argv) > 1:
+    if sys.argv[1] == "--modversion":
+        if sys.argv[2] == "test-package-0.0":
+            print("0.0.0")
+        else:
+            exit(-1)
+    elif sys.argv[1] == "--version":
+        print("0.0.0")
+        exit(0)

test cases/common/279 pkgconfig override/subprojects/pkg-config/meson.build

@@ -0,0 +1,4 @@
+project('pkg-config')
+
+pkgconfig = find_program(meson.project_source_root() / 'bin' / 'pkg-config.py')
+meson.override_find_program('pkg-config', pkgconfig)

test cases/unit/116 empty project/expected_mods.json

@@ -188,6 +188,7 @@
       "mesonbuild.dependencies",
       "mesonbuild.dependencies.base",
       "mesonbuild.dependencies.detect",
+      "mesonbuild.dependencies.pkgconfig",
       "mesonbuild.depfile",
       "mesonbuild.envconfig",
       "mesonbuild.environment",