feat: Add libcap dep for BYOB

Bug: b/365562310
Change-Id: I7959c1436228476d1c4ca6ae761cd08f9925eea8
GitOrigin-RevId: 5efdc27513073d7829ef1fc9d8ab64f2d4da5ba2

build_defs/cc/shared/build_targets/libcap.BUILD

@@ -0,0 +1,115 @@
+# Copyright 2024 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+load("@rules_cc//cc:defs.bzl", "cc_binary", "cc_library", "cc_test")
+
+package(default_visibility = ["//visibility:public"])
+
+genrule(
+    name = "cap_names_list_h",
+    srcs = ["libcap/include/uapi/linux/capability.h"],
+    outs = ["cap_names.list.h"],
+    # Use the same logic as libcap/Makefile
+    cmd = """
+    perl -e 'while ($$l=<>) {
+      if ($$l =~ /^\\#define[ \\t](CAP[_A-Z]+)[ \\t]+([0-9]+)\\s+$$/) {
+        $$tok=$$1; $$val=$$2; $$tok =~ tr/A-Z/a-z/;
+        print \"{\\\"$$tok\\\",$$val},\\n\"; } }' $< \
+    | fgrep -v 0x > $@
+    """,
+)
+
+cc_library(
+    name = "makenames_textual_hdrs",
+    textual_hdrs = [
+        "cap_names.list.h",
+        "libcap/include/uapi/linux/capability.h",
+    ],
+    visibility = ["//visibility:private"],
+)
+
+cc_binary(
+    name = "makenames",
+    srcs = [
+        "libcap/_makenames.c",
+        "libcap/include/sys/capability.h",
+    ],
+    includes = [
+        "libcap/..",
+        "libcap/include",
+        "libcap/include/uapi",
+    ],
+    deps = [
+        ":makenames_textual_hdrs",
+    ],
+)
+
+genrule(
+    name = "cap_names_h",
+    outs = ["libcap/cap_names.h"],
+    cmd = "mkdir -p libcap && $(location makenames) > $@ || { rm -f $@; false; }",
+    tools = [":makenames"],
+)
+
+cc_library(
+    name = "libcap",
+    srcs = [
+        "libcap/cap_alloc.c",
+        "libcap/cap_extint.c",
+        "libcap/cap_file.c",
+        "libcap/cap_flag.c",
+        "libcap/cap_names.h",
+        "libcap/cap_proc.c",
+        "libcap/cap_text.c",
+        "libcap/libcap.h",
+    ],
+    copts = [
+        "-Wno-tautological-compare",
+        "-Wno-unused-result",
+    ],
+    includes = [
+        "libcap",
+        "libcap/include",
+        "libcap/include/uapi",
+    ],
+    textual_hdrs = [
+        "libcap/include/sys/capability.h",
+        "libcap/include/sys/securebits.h",
+        "libcap/include/uapi/linux/capability.h",
+        "libcap/include/uapi/linux/prctl.h",
+        "libcap/include/uapi/linux/securebits.h",
+    ],
+)
+
+cc_test(
+    name = "cap_test",
+    size = "small",
+    srcs = [
+        "libcap/cap_names.h",
+        "libcap/cap_test.c",
+        "libcap/libcap.h",
+    ],
+    deps = [
+        ":libcap",
+    ],
+)
+
+cc_test(
+    name = "libcap_test",
+    size = "small",
+    deps = [
+        ":libcap",
+        "@com_google_googletest//:gtest_main",
+    ],
+)

build_defs/cc/shared/cc_utils.bzl

@@ -96,3 +96,14 @@ def _gvisor_utils(version = GVISOR_VERSION):
         sha256 = "45d32d3c7ff9bf455a94c3ba3021ad4ae9c3619ce680faf880dc50b49eb2ed48",
         urls = ["{}/aarch64/containerd-shim-runsc-v1".format(release_url)],
     )
+
+    maybe(
+        http_archive,
+        name = "libcap",
+        build_file = Label("//build_defs/cc/shared/build_targets:libcap.BUILD"),
+        sha256 = "18f00ea97c7541af86379dec9d4d8ea838aac4a1f70177d81d91657e4e43b808",
+        strip_prefix = "libcap-2.70",
+        urls = [
+            "https://git.kernel.org/pub/scm/libs/libcap/libcap.git/snapshot/libcap-2.70.tar.gz",
+        ],
+    )