continue on refbindings

README.md

@@ -203,7 +203,7 @@ As pypdfium2 requires a C extension and has custom setup code, there are some sp
   - It is possible to prepend `prepared!` to install with existing platform files instead of generating on the fly; the value will be used for metadata / file inclusion. This can be helpful when installing in an isolated env where ctypesgen is not available, but it is not desirable to use the reference bindings (e.g. conda).
 
 * `$PYPDFIUM_MODULES=[raw,helpers]` defines the modules to include. Metadata adapts dynamically.
-  - May be used by packagers to decouple raw bindings and helpers, which can be important if packaging against system pdfium.
+  - May be used by packagers to decouple raw bindings and helpers, which may be relevant if packaging against system pdfium.
   - Would also allow to install only the raw module without helpers, or only helpers with a custom raw module.
 
 * `$PDFIUM_BINDINGS=reference` allows to override ctypesgen and use the reference bindings file `autorelease/bindings.py` instead.

setupsrc/pypdfium2_setup/autorelease.py

@@ -22,12 +22,8 @@ def run_local(*args, **kws):
 
 
 def update_refbindings(version):
-    # We endeavor to make the reference bindings as universal and robust as possible.
-    # Thanks to symbol guards, we can define all standalone feature flags.
-    # We don't currently define flags that depend on external headers, though it should be possible in principle by adding them to $CPATH (or equivalent). Further, if we could get OS headers, this might even allow for cross-compilation with OS flags (e.g. _WIN32).
-    # Note that Skia is currently a standalone flag because pdfium only provides a typedef void* for a Skia canvas and casts internally
     RefBindingsFile.unlink()
-    build_pdfium_bindings(version, guard_symbols=True, flags=["V8", "XFA", "SKIA"], allow_system_despite_libdirs=True)
+    build_pdfium_bindings(version, guard_symbols=True, flags=REFBINDINGS_FLAGS, allow_system_despite_libdirs=True)
     shutil.copyfile(DataDir_Bindings/BindingsFN, RefBindingsFile)
     assert RefBindingsFile.exists()
 

setupsrc/pypdfium2_setup/packaging_base.py

@@ -63,6 +63,13 @@
 ReleaseInfoURL = ReleaseURL.replace("github.com/", "api.github.com/repos/").replace("download/", "tags/")
 
 
+# We endeavor to make the reference bindings as universal and robust as possible.
+# Thanks to symbol guards, we can define all standalone feature flags.
+# We don't currently define flags that depend on external headers, though it should be possible in principle by adding them to $CPATH (or equivalent). Further, if we could get OS headers, this might even allow for cross-compilation with OS flags (e.g. _WIN32).
+# Note that Skia is currently a standalone flag because pdfium only provides a typedef void* for a Skia canvas and casts internally
+REFBINDINGS_FLAGS = ["V8", "XFA", "SKIA"]
+
+
 # TODO make SysNames/ExtPlats/PlatNames iterable, consider StrEnum or something
 
 class SysNames:
@@ -421,7 +428,7 @@ def run_ctypesgen(target_dir, headers_dir, flags=[], guard_symbols=False, compil
     bindings.write_text(text)
 
 
-def build_pdfium_bindings(version, headers_dir=None, **kwargs):
+def build_pdfium_bindings(version, headers_dir=None, flags=[], **kwargs):
     defaults = dict(flags=[], run_lds=["."], guard_symbols=False)
     for k, v in defaults.items():
         kwargs.setdefault(k, v)
@@ -431,13 +438,19 @@ def build_pdfium_bindings(version, headers_dir=None, **kwargs):
     if not headers_dir:
         headers_dir = DataDir_Bindings / "headers"
 
-    # TODO move refbindings handling into run_ctypesgen on behalf of sourcebuild?
     # quick and dirty patch to allow using the pre-built bindings instead of calling ctypesgen
+    # TODO move handler into run_ctypesgen on behalf of sourcebuild?
     if BindTarget == BindTarget_Ref:
-        print("Using refbindings as requested by env var. Note that this will bypass all bindings params (e.g. flags). The refbindings try to be as universal as possible, though.", file=sys.stderr)
+        print("Using reference bindings as requested by env var. This will bypass all bindings params.", file=sys.stderr)
+        record = read_json(AR_RecordFile)
+        bindings_ver = record["pdfium"]
+        if bindings_ver != version:
+            print(f"Warning: ABI version mismatch (bindings {bindings_ver}, binary target {version}). This is potentially unsafe!", file=sys.stderr)
+        flags_diff = set(flags).difference(REFBINDINGS_FLAGS)
+        if flags_diff:  # == not set(...).issubset(...)
+            print(f"Warning: The following requested flags are not available in the reference bindings and will be discarded: {flags_diff}")
         shutil.copyfile(RefBindingsFile, DataDir_Bindings/BindingsFN)
-        ar_record = read_json(AR_RecordFile)
-        write_json(ver_path, dict(version=ar_record["pdfium"], flags=[], run_lds=["."], source="reference"))
+        write_json(ver_path, dict(version=bindings_ver, flags=REFBINDINGS_FLAGS, run_lds=["."], source="reference"))
         return
 
     curr_info = dict(