meson: Wire up project version detection

compat/build.py

@@ -280,6 +280,7 @@ def call_internal_meson(argv, *args, **kwargs):
     source_paths: set[Path] = set()
     options: Optional[Sequence[str]] = None
     build_env = scrub_environment(os.environ)
+    build_env["FRIDA_RELENG"] = str(releng_location)
     for key, outputs in state.outputs.items():
         if key == "bundle":
             for o in outputs:

meson.build

@@ -1,5 +1,7 @@
 project('frida-core', 'vala', 'c', 'cpp',
-  version: '0.0.0',
+  version: run_command(find_program('python3'), files('tools' / 'detect-version.py'),
+    capture: true,
+    check: true).stdout().strip(),
   meson_version: '>=1.1.0',
   default_options: ['c_std=gnu99,c99', 'cpp_std=c++17'],
 )

tools/detect-version.py

@@ -0,0 +1,44 @@
+import os
+from pathlib import Path
+import sys
+from typing import Iterator
+
+
+REPO_DIR = Path(__file__).resolve().parent.parent
+
+
+def detect_version() -> str:
+    releng_location = next(enumerate_releng_locations(), None)
+    if releng_location is not None:
+        sys.path.insert(0, str(releng_location.parent))
+        from releng.frida_version import detect
+        version = detect(REPO_DIR).name
+    else:
+        version = "0.0.0"
+    return version
+
+
+def enumerate_releng_locations() -> Iterator[Path]:
+    val = os.environ.get("FRIDA_RELENG")
+    if val is not None:
+        custom_releng = Path(val)
+        if releng_location_exists(custom_releng):
+            yield custom_releng
+
+    val = os.environ.get("MESON_SOURCE_ROOT")
+    if val is not None:
+        parent_releng = Path(val) / "releng"
+        if releng_location_exists(parent_releng):
+            yield parent_releng
+
+    local_releng = REPO_DIR / "releng"
+    if releng_location_exists(local_releng):
+        yield local_releng
+
+
+def releng_location_exists(location: Path) -> bool:
+    return (location / "frida_version.py").exists()
+
+
+if __name__ == "__main__":
+    print(detect_version())