fix: place openmsx system ROMs through filepool

openMSX reads share/systemroms below OPENMSX_HOME or ~/.openMSX and
every filepool entry by SHA1. The profile paths drop RetroBat's
openmsx/ prefix and declare those directories and the filepool.

Batocera's config_directories reads the filepool lines its generator
writes, KNULLI reuses it. RetroBat records OPENMSX_HOME, RetroPie the
moveConfigDir of ~/.openMSX that its systemroms link lies in, and the
configure --prefix of xroar that its roms link lies in.

Batocera and KNULLI system ROMs move from openmsx/share/systemroms to
openmsx/, beside the files their own lists declare, RetroPie's to
BIOS/openmsx, the folder linked as share/systemroms.

scripts/scraper/batocera_launchers.py

@@ -15,7 +15,8 @@ launcher looks for nothing".
 from __future__ import annotations
 
 import ast
-from collections.abc import Callable
+import re
+from collections.abc import Callable, Iterable
 from typing import Any
 
 from .configgen_launchers import (
@@ -898,6 +899,56 @@ def environment_directories(cg: Configgen) -> list[Launcher]:
     return launchers
 
 
+# Generators that hand the emulator a /userdata/bios directory through its
+# configuration: a line written to the file it reads (openMSX's script.tcl
+# filepool entries) or a key saved to it.
+CONFIG_DIRECTORY_GENERATORS = ("openmsx.openmsxGenerator",)
+
+
+def config_directories(
+    cg: Configgen, modules: Iterable[str] = CONFIG_DIRECTORY_GENERATORS
+) -> list[Launcher]:
+    """file.write("<line naming a BIOS directory>") and settings.save(key, <BIOS directory>)."""
+    prefix = cg.bios.rstrip("/")
+    inside = re.compile(rf"{re.escape(prefix)}(?:/[^\s\"';]*)?")
+    launchers = []
+    for module in modules:
+        src = cg.generator(module)
+        constants = dict(cg.paths)
+        for node in src.tree.body:
+            name = _assigned_name(node)
+            value = _path_value(getattr(node, "value", None), constants)
+            if name is not None and value is not None:
+                constants[name] = value
+        found: list[tuple[str, str, ast.Call]] = []
+        for call in _calls(src.tree, attr="write"):
+            text = call.args[0] if len(call.args) == 1 else None
+            if isinstance(text, ast.Constant) and isinstance(text.value, str):
+                line = text.value.strip()
+                named = inside.search(line)
+                if named:
+                    found.append((named.group(0), f"written: {line}", call))
+        for call in _calls(src.tree, attr="save"):
+            if len(call.args) != 2 or not isinstance(call.args[0], ast.Constant):
+                continue
+            value = _path_value(call.args[1], constants)
+            if value is None and isinstance(call.args[1], ast.Constant):
+                value = str(call.args[1].value)
+            if value is not None and (value.rstrip("/") == prefix or value.startswith(prefix + "/")):
+                found.append((value, str(call.args[0].value), call))
+        if not found:
+            src.fail("hands no /userdata/bios directory through its config")
+        launchers.extend(
+            Launcher(
+                emulator=cg.emulator(module), build="standalone", kind="passes_path",
+                names=[], search_dir=directory, passes_to=passes_to,
+                source_ref=src.ref([src.span(call)]),
+            )
+            for directory, passes_to, call in found
+        )
+    return launchers
+
+
 # libretro core options whose value names the BIOS file the core opens.
 FILE_OPTIONS = (("_o2em_options", "o2em_bios"), ("_neocd_options", "neocd_bios"))
 
@@ -952,7 +1003,8 @@ def core_file_options(cg: Configgen) -> list[Launcher]:
 
 EXTRACTORS: tuple[Callable[[Configgen], list[Launcher]], ...] = (
     duckstation, duckstation_legacy, hatari, xemu, melonds, mupen64plus,
-    x16emu, gsplus, lexaloffle, environment_directories, core_file_options,
+    x16emu, gsplus, lexaloffle, environment_directories, config_directories,
+    core_file_options,
 )
 
 

scripts/scraper/knulli_launchers.py

@@ -31,6 +31,7 @@ import yaml
 try:
     from .batocera_launchers import (
         Configgen,
+        config_directories,
         _path_value,
         _render,
         _system_branches,
@@ -53,6 +54,7 @@ try:
 except ImportError:
     from batocera_launchers import (  # type: ignore[no-redef]
         Configgen,
+        config_directories,
         _path_value,
         _render,
         _system_branches,
@@ -84,9 +86,18 @@ PICO8_INSTALLER = "board/fsoverlay/usr/bin/knulli-install-pico8"
 ES_FEATURES = "package/emulationstation/knulli-es-system/es_features.yml"
 
 # Batocera's extractors that read KNULLI's generators unchanged.
+# The generators of Batocera's config_directories that KNULLI keeps in the
+# same shape: openMSX's filepool lines.
+CONFIG_DIRECTORY_GENERATORS = ("openmsx.openmsxGenerator",)
+
+
+def knulli_config_directories(cg: Configgen) -> list[Launcher]:
+    return config_directories(cg, CONFIG_DIRECTORY_GENERATORS)
+
+
 SHARED = (
     duckstation, duckstation_legacy, hatari, xemu, melonds, mupen64plus, x16emu,
-    environment_directories,
+    environment_directories, knulli_config_directories,
 )
 
 
@@ -365,7 +376,6 @@ GENERIC_SITES = (
     GenericSites("amiberry/amiberryGenerator.py", "passes_path"),
     GenericSites("fsuae/fsuaeGenerator.py", "passes_path"),
     GenericSites("mame/mameGenerator.py", "passes_path"),
-    GenericSites("openmsx/openmsxGenerator.py", "passes_path"),
     GenericSites("fpinball/fpinballGenerator.py", "passes_path"),
     GenericSites(
         "libretro/libretroRetroarchCustom.py", "passes_path", "libretro", emulator="retroarch"

scripts/scraper/retrobat_launchers.py

@@ -1279,6 +1279,29 @@ def openmsx(sources: dict[str, Source]) -> list[Record]:
         )
     if not records:
         raise LauncherPatternMissing(src.path, "biosFiles entries")
+    # OPENMSX_HOME is the user directory: openMSX reads share/systemroms below it.
+    home = src.find(
+        rf'string (\w+) = Path\.Combine\({BIOS}, "([^"]+)"\);', "OPENMSX_HOME folder"
+    )
+    handed = src.find(
+        rf'ret\.EnvironmentVariables\["(OPENMSX_HOME)"\] = {home.group(1)};',
+        "OPENMSX_HOME environment", home.end(),
+    )
+    records.append(
+        _record(
+            "openmsx",
+            "standalone",
+            "passes_path",
+            [],
+            source_ref(
+                (src.path, [src.lines(home.start(), home.end()),
+                            src.lines(handed.start(), handed.end())])
+            ),
+            search_dir=f"bios/{home.group(2)}",
+            passes_to=f"environment {handed.group(1)}",
+            fails_when_missing=False,
+        )
+    )
     return records
 
 

scripts/scraper/retropie_launchers.py

@@ -525,6 +525,7 @@ class PackageReader:
             self._links(links)
         self._outside_bios(events)
         self._working_directory(events)
+        self._reaching_links(events)
         return self.records
 
     @staticmethod
@@ -828,6 +829,54 @@ class PackageReader:
             )
 
 
+    def _reaching_links(self, events: list[Event]) -> None:
+        """The directories outside the BIOS one that a whole-directory link lies in.
+
+        openmsx's moveConfigDir "$home/.openMSX" "$configdir/msx/openmsx"
+        puts the emulator's directory where the systemroms link to BIOS/openmsx
+        lies, and xroar's ./configure --prefix="$md_inst" builds the program
+        whose share/xroar/roms links to $biosdir. Neither line names the BIOS
+        directory, and each says where the link is read from.
+        """
+        suffix = " is a symlink to it"
+        linked = [
+            record.passes_to.removesuffix(suffix).rstrip("/")
+            for record in self.records
+            if record.kind == "links" and not record.names
+            and (record.passes_to or "").endswith(suffix)
+        ]
+        if not linked:
+            return
+
+        def holds(directory: str) -> bool:
+            directory = directory.strip("\"'").rstrip("/")
+            return bool(directory) and any(
+                path == directory or path.startswith(directory + "/") for path in linked
+            )
+
+        for event in events:
+            if event.heredoc or not event.words or _mentions_bios(event.raw):
+                continue
+            command = event.words[0][0]
+            if command == "moveConfigDir" and len(event.words) >= 3:
+                link, real = event.words[1][0], event.words[2][0]
+                if holds(real):
+                    self.record(
+                        "links", [], [(event.path, event.line)],
+                        search_dir=real, passes_to=f"{link}{suffix}",
+                        fails_when_missing=False, depends_on_option=self._depends(event),
+                    )
+            elif command.endswith("configure"):
+                for word in event.words[1:]:
+                    prefix = word[0].strip("\"'")
+                    if prefix.startswith("--prefix=") and holds(prefix[len("--prefix="):]):
+                        self.record(
+                            "passes_path", [], [(event.path, event.line)],
+                            search_dir=prefix[len("--prefix="):].strip("\"'"),
+                            passes_to="${prefix} of configure --prefix",
+                            fails_when_missing=False, depends_on_option=self._depends(event),
+                        )
+
     def _working_directory(self, events: list[Event]) -> None:
         """The folder a generated launch script enters before it runs the emulator."""
         if self.package.id not in WORKING_DIRECTORY: