1 files changed, 95 insertions, 0 deletions
diff --git a/python/mozbuild/mozbuild/action/generate_symbols_file.py b/python/mozbuild/mozbuild/action/generate_symbols_file.py
new file mode 100644
index 0000000000..955a676c08
--- /dev/null
+++ b/python/mozbuild/mozbuild/action/generate_symbols_file.py
@@ -0,0 +1,95 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+import argparse
+import os
+from io import StringIO
+
+import buildconfig
+
+from mozbuild.preprocessor import Preprocessor
+from mozbuild.util import DefinesAction
+
+
+def generate_symbols_file(output, *args):
+    """ """
+    parser = argparse.ArgumentParser()
+    parser.add_argument("input")
+    parser.add_argument("-D", action=DefinesAction)
+    parser.add_argument("-U", action="append", default=[])
+    args = parser.parse_args(args)
+    input = os.path.abspath(args.input)
+
+    pp = Preprocessor()
+    pp.context.update(buildconfig.defines["ALLDEFINES"])
+    if args.D:
+        pp.context.update(args.D)
+    for undefine in args.U:
+        if undefine in pp.context:
+            del pp.context[undefine]
+    # Hack until MOZ_DEBUG_FLAGS are simply part of buildconfig.defines
+    if buildconfig.substs.get("MOZ_DEBUG"):
+        pp.context["DEBUG"] = "1"
+    # Ensure @DATA@ works as expected (see the Windows section further below)
+    if buildconfig.substs["OS_TARGET"] == "WINNT":
+        pp.context["DATA"] = "DATA"
+    else:
+        pp.context["DATA"] = ""
+    pp.out = StringIO()
+    pp.do_filter("substitution")
+    pp.do_include(input)
+
+    symbols = [s.strip() for s in pp.out.getvalue().splitlines() if s.strip()]
+
+    libname, ext = os.path.splitext(os.path.basename(output.name))
+
+    if buildconfig.substs["OS_TARGET"] == "WINNT":
+        # A def file is generated for MSVC link.exe that looks like the
+        # following:
+        # LIBRARY library.dll
+        # EXPORTS
+        #   symbol1
+        #   symbol2
+        #   ...
+        #
+        # link.exe however requires special markers for data symbols, so in
+        # that case the symbols look like:
+        #   data_symbol1 DATA
+        #   data_symbol2 DATA
+        #   ...
+        #
+        # In the input file, this is just annotated with the following syntax:
+        #   data_symbol1 @DATA@
+        #   data_symbol2 @DATA@
+        #   ...
+        # The DATA variable is "simply" expanded by the preprocessor, to
+        # nothing on non-Windows, such that we only get the symbol name on
+        # those platforms, and to DATA on Windows, so that the "DATA" part
+        # is, in fact, part of the symbol name as far as the symbols variable
+        # is concerned.
+        assert ext == ".def"
+        output.write("LIBRARY %s\nEXPORTS\n  %s\n" % (libname, "\n  ".join(symbols)))
+    elif (
+        buildconfig.substs.get("GCC_USE_GNU_LD")
+        or buildconfig.substs["OS_TARGET"] == "SunOS"
+    ):
+        # A linker version script is generated for GNU LD that looks like the
+        # following:
+        # liblibrary.so {
+        # global:
+        #   symbol1;
+        #   symbol2;
+        #   ...
+        # local:
+        #   *;
+        # };
+        output.write(
+            "%s {\nglobal:\n  %s;\nlocal:\n  *;\n};" % (libname, ";\n  ".join(symbols))
+        )
+    elif buildconfig.substs["OS_TARGET"] == "Darwin":
+        # A list of symbols is generated for Apple ld that simply lists all
+        # symbols, with an underscore prefix.
+        output.write("".join("_%s\n" % s for s in symbols))
+
+    return set(pp.includes)