add support for cc_shared_library deps (#1243)

Author: matt-sm

MODULE.bazel

@@ -6,6 +6,7 @@ module(
     compatibility_level = 1,
 )
 
+bazel_dep(name = "bazel_features", version = "1.15.0")
 bazel_dep(name = "bazel_skylib", version = "1.3.0")
 bazel_dep(name = "platforms", version = "0.0.5")
 bazel_dep(name = "rules_python", version = "0.23.1")

WORKSPACE.bazel

@@ -10,6 +10,10 @@ local_repository(
     path = "examples",
 )
 
+load("@bazel_features//:deps.bzl", "bazel_features_deps")
+
+bazel_features_deps()
+
 load("@bazel_skylib//:workspace.bzl", "bazel_skylib_workspace")
 
 bazel_skylib_workspace()

docs/WORKSPACE.bazel

@@ -9,6 +9,10 @@ load("@rules_foreign_cc//foreign_cc:repositories.bzl", "rules_foreign_cc_depende
 
 rules_foreign_cc_dependencies()
 
+load("@bazel_features//:deps.bzl", "bazel_features_deps")
+
+bazel_features_deps()
+
 load("//:stardoc_repository.bzl", "stardoc_repository")
 
 stardoc_repository()

examples/third_party/zlib/BUILD.bazel

@@ -1,4 +1,5 @@
 load("@rules_cc//cc:defs.bzl", "cc_binary")
+load("@rules_foreign_cc//foreign_cc:defs.bzl", "cmake", "runnable_binary")
 
 exports_files(
     [
@@ -7,6 +8,15 @@ exports_files(
     visibility = ["//visibility:public"],
 )
 
+filegroup(
+    name = "shared_usage_srcs",
+    srcs = [
+        "CMakeLists.txt",
+        "zlib-example.cpp",
+    ],
+    visibility = ["//visibility:public"],
+)
+
 cc_binary(
     name = "zlib_usage_example",
     srcs = ["zlib-example.cpp"],
@@ -19,3 +29,24 @@ sh_test(
     data = [":zlib_usage_example"],
     visibility = ["//:__pkg__"],
 )
+
+cmake(
+    name = "zlib_shared_usage_example",
+    dynamic_deps = ["@zlib//:zlib_shared"],
+    lib_source = "shared_usage_srcs",
+    out_binaries = ["zlib-example"],
+    deps = ["@zlib//:zlib_static"],
+)
+
+runnable_binary(
+    name = "run-zlib-example",
+    binary = "zlib-example",
+    foreign_cc_target = ":zlib_shared_usage_example",
+)
+
+sh_test(
+    name = "test_shared_zlib",
+    srcs = ["test_shared_zlib.sh"],
+    data = [":run-zlib-example"],
+    visibility = ["//:__pkg__"],
+)

examples/third_party/zlib/BUILD.zlib.bazel

@@ -1,3 +1,4 @@
+load("@rules_cc//cc:defs.bzl", "cc_library")
 load("@rules_foreign_cc//foreign_cc:defs.bzl", "cmake")
 
 package(default_visibility = ["//visibility:public"])
@@ -28,3 +29,53 @@ cmake(
         "//conditions:default": ["libz.a"],
     }),
 )
+
+cc_library(
+    name = "zlib_static",
+    srcs = [
+        "adler32.c",
+        "compress.c",
+        "crc32.c",
+        "deflate.c",
+        "gzclose.c",
+        "gzlib.c",
+        "gzread.c",
+        "gzwrite.c",
+        "infback.c",
+        "inffast.c",
+        "inflate.c",
+        "inftrees.c",
+        "trees.c",
+        "uncompr.c",
+        "zutil.c",
+    ],
+    hdrs = [
+        "crc32.h",
+        "deflate.h",
+        "gzguts.h",
+        "inffast.h",
+        "inffixed.h",
+        "inflate.h",
+        "inftrees.h",
+        "trees.h",
+        "zconf.h",
+        "zlib.h",
+        "zutil.h",
+    ],
+    copts = select({
+        "@platforms//os:windows": [],
+        "//conditions:default": [
+            "-Wno-deprecated-non-prototype",
+            "-Wno-unused-variable",
+            "-Wno-implicit-function-declaration",
+        ],
+    }),
+    includes = ["."],
+    linkstatic = True,
+)
+
+cc_shared_library(
+    name = "zlib_shared",
+    shared_lib_name = "libz.so",
+    deps = ["zlib_static"],
+)

examples/third_party/zlib/CMakeLists.txt

@@ -0,0 +1,13 @@
+cmake_minimum_required(VERSION 3.15)
+
+project(zlib-example)
+
+find_package(ZLIB REQUIRED)
+
+set(SRCS zlib-example.cpp)
+
+add_executable(${PROJECT_NAME} ${SRCS})
+
+target_link_libraries(${PROJECT_NAME} ZLIB::ZLIB)
+
+install(TARGETS ${PROJECT_NAME} DESTINATION bin)

examples/third_party/zlib/test_shared_zlib.sh

@@ -0,0 +1,3 @@
+#!/usr/bin/env bash
+
+$(rlocation rules_foreign_cc/examples/cmake/zlib_shared_usage_example)

foreign_cc/private/BUILD.bazel

@@ -44,6 +44,7 @@ bzl_library(
         "//foreign_cc:providers",
         "//foreign_cc/private/framework:helpers",
         "//foreign_cc/private/framework:platform",
+        "@bazel_features//:features",
         "@bazel_skylib//lib:collections",
         "@bazel_skylib//lib:paths",
         "@bazel_tools//tools/cpp:toolchain_utils.bzl",

foreign_cc/private/framework.bzl

@@ -2,6 +2,7 @@
  with CMake, configure/make, autotools)
 """
 
+load("@bazel_features//:features.bzl", "bazel_features")
 load("@bazel_skylib//lib:collections.bzl", "collections")
 load("@bazel_skylib//lib:paths.bzl", "paths")
 load("@bazel_tools//tools/cpp:toolchain_utils.bzl", "find_cpp_toolchain")
@@ -98,6 +99,14 @@ CC_EXTERNAL_RULE_ATTRIBUTES = {
         default = [],
         providers = [CcInfo],
     ),
+    "dynamic_deps": attr.label_list(
+        doc = (
+            "Same as deps but for cc_shared_library."
+        ),
+        mandatory = False,
+        default = [],
+        # providers = [CcSharedLibraryInfo],
+    ),
     "env": attr.string_dict(
         doc = (
             "Environment variables to set during the build. " +
@@ -866,6 +875,19 @@ def _define_inputs(attrs):
             bazel_system_includes += headers_info.include_dirs
             bazel_libs += _collect_libs(dep[CcInfo].linking_context)
 
+    for dynamic_dep in attrs.dynamic_deps:
+        if not bazel_features.globals.CcSharedLibraryInfo:
+            fail("CcSharedLibraryInfo is only available in Bazel 7 or greater")
+
+        linker_input = dynamic_dep[bazel_features.globals.CcSharedLibraryInfo].linker_input
+        bazel_libs += _collect_shared_libs(linker_input)
+        linking_context = cc_common.create_linking_context(
+            linker_inputs = depset(direct = [linker_input]),
+        )
+
+        # create a new CcInfo from the CcSharedLibraryInfo linker_input
+        cc_infos.append(CcInfo(linking_context = linking_context))
+
     # Keep the order of the transitive foreign dependencies
     # (the order is important for the correct linking),
     # but filter out repeating directories
@@ -989,6 +1011,14 @@ def _collect_libs(cc_linking):
                     libs.append(library)
     return collections.uniq(libs)
 
+def _collect_shared_libs(cc_linker_input):
+    libs = []
+    for library_to_link in cc_linker_input.libraries:
+        for library in _extract_libraries(library_to_link):
+            if library:
+                libs.append(library)
+    return collections.uniq(libs)
+
 def expand_locations_and_make_variables(ctx, unexpanded, attr_name, data):
     """Expand locations and make variables while ensuring that `execpath` is always set to an absolute path
 

foreign_cc/repositories.bzl

@@ -83,6 +83,14 @@ def rules_foreign_cc_dependencies(
     if register_preinstalled_tools:
         preinstalled_toolchains()
 
+    maybe(
+        http_archive,
+        name = "bazel_features",
+        sha256 = "ba1282c1aa1d1fffdcf994ab32131d7c7551a9bc960fbf05f42d55a1b930cbfb",
+        strip_prefix = "bazel_features-1.15.0",
+        url = "https://github.com/bazel-contrib/bazel_features/releases/download/v1.15.0/bazel_features-v1.15.0.tar.gz",
+    )
+
     maybe(
         http_archive,
         name = "bazel_skylib",