xgl-generate.py: add LayerGetProcAddrHelperSubcommand()

It generates layer_intercept_proc() to intercept all but
xglInitAndEnumerateGpus().  It is possible to extend the subcommand to get the
list of functions to intercept from command arguments or layer spec files.
But we do not have the needs yet.

1 files changed, 43 insertions, 0 deletions

diff --git a/xgl-generate.py b/xgl-generate.py
index eecf71b5..75a22313 100755
--- a/xgl-generate.py
+++ b/xgl-generate.py
@@ -321,12 +321,55 @@ class IcdGetProcAddrSubcommand(IcdDummyEntrypointsSubcommand):
 
         return "\n".join(body)
 
+class LayerInterceptProcSubcommand(Subcommand):
+    def run(self):
+        self.prefix = "xgl"
+
+        # we could get the list from argv if wanted
+        self.intercepted = [proto.name for proto in self.protos
+                if proto.name not in ["InitAndEnumerateGpus"]]
+
+        for proto in self.protos:
+            if proto.name == "GetProcAddr":
+                self.gpa = proto
+
+        super().run()
+
+    def generate_header(self):
+        return "\n".join(["#include <string.h>", "#include \"xglLayer.h\""])
+
+    def generate_body(self):
+        lookups = []
+        for proto in self.protos:
+            if proto.name not in self.intercepted:
+                lookups.append("/* no %s%s */" % (self.prefix, proto.name))
+                continue
+
+            lookups.append("if (!strcmp(name, \"%s\"))" % proto.name)
+            lookups.append("    return (%s) %s%s;" %
+                    (self.gpa.ret, self.prefix, proto.name))
+
+        body = []
+        body.append("static inline %s layer_intercept_proc(const char *name)" %
+                self.gpa.ret)
+        body.append("{")
+        body.append(generate_get_proc_addr_check("name"))
+        body.append("")
+        body.append("    name += 3;")
+        body.append("    %s" % "\n    ".join(lookups))
+        body.append("")
+        body.append("    return NULL;")
+        body.append("}")
+
+        return "\n".join(body)
+
 def main():
     subcommands = {
             "loader-entrypoints": LoaderEntrypointsSubcommand,
             "dispatch-table-ops": DispatchTableOpsSubcommand,
             "icd-dummy-entrypoints": IcdDummyEntrypointsSubcommand,
             "icd-get-proc-addr": IcdGetProcAddrSubcommand,
+            "layer-intercept-proc": LayerInterceptProcSubcommand,
     }
 
     if len(sys.argv) < 2 or sys.argv[1] not in subcommands: