Support generating flag-files for prebuilt libraries

1 files changed, 75 insertions, 0 deletions

diff --git a/CC/prebuilt/read_pkgconfig.py b/CC/prebuilt/read_pkgconfig.py
new file mode 100755
index 0000000..cb4154f
--- /dev/null
+++ b/CC/prebuilt/read_pkgconfig.py
@@ -0,0 +1,75 @@
+#!/usr/bin/env python3
+# Copyright 2023 Huawei Cloud Computing Technology Co., Ltd.
+#
+# 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.
+
+import os
+import subprocess
+import sys
+from pathlib import Path
+
+
+def run_pkgconfig(args: list[str], env: dict[str, str]) -> str:
+    result = subprocess.run(["pkg-config"] + args, env=env, capture_output=True)
+    if result.returncode != 0:
+        print(result.stderr.decode("utf-8"), file=sys.stderr)
+        exit(1)
+    return result.stdout.decode("utf-8").strip()
+
+
+def read_ldflags(pkg: str, env: dict[str, str]) -> str:
+    def libname(filename: str) -> str:
+        return filename.split(".")[0]
+
+    local_libs = {
+        libname(f)
+        for it in os.walk(".") for f in it[2] if f.startswith("lib")
+    }
+
+    link_flags = run_pkgconfig(["--libs-only-l", pkg], env).split(" ")
+
+    # deduplicate, keep right-most
+    seen: set[str] = set()
+    link_flags = [
+        f for f in link_flags[::-1] if f not in seen and not seen.add(f)
+    ][::-1]
+
+    def is_local(flag: str) -> bool:
+        if not flag.startswith("-l"):
+            return False
+        lib = libname(flag[3:]) if flag.startswith("-l:") else f"lib{flag[2:]}"
+        return lib in local_libs
+
+    return " ".join([f for f in link_flags if not is_local(f)])
+
+
+def read_pkgconfig():
+    if len(sys.argv) < 3:
+        print(f"usage: read_pkgconfig OUT_NAME PC_FILE")
+        exit(1)
+
+    name = sys.argv[1]
+    pkg = Path(sys.argv[2]).stem
+    env = dict(os.environ, PKG_CONFIG_PATH="./lib/pkgconfig")
+
+    if name.endswith(".cflags"):
+        data = run_pkgconfig(["--cflags-only-other", pkg], env)
+    else:
+        data = read_ldflags(pkg, env)
+
+    with open(f"{name}", 'w') as f:
+        f.write(data)
+
+
+if __name__ == "__main__":
+    read_pkgconfig()