loader: Separate out the python generator script

Loader is a reference component. Intel driver is a sample component. Loader
should not be sharing files with driver. This is a first step in that direction.
Also loader has special cases that are not in driver or layers. So it simplifies
their scripts not to have loader baggage in them.
diff --git a/loader/vk-loader-generate.py b/loader/vk-loader-generate.py
new file mode 100755
index 0000000..ab6645f
--- /dev/null
+++ b/loader/vk-loader-generate.py
@@ -0,0 +1,431 @@
+#!/usr/bin/env python3
+#
+# VK
+#
+# Copyright (C) 2014 LunarG, Inc.
+#
+# Permission is hereby granted, free of charge, to any person obtaining a
+# copy of this software and associated documentation files (the "Software"),
+# to deal in the Software without restriction, including without limitation
+# the rights to use, copy, modify, merge, publish, distribute, sublicense,
+# and/or sell copies of the Software, and to permit persons to whom the
+# Software is furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be included
+# in all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+# THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+# FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+# DEALINGS IN THE SOFTWARE.
+#
+
+import os, sys
+
+# add main repo directory so vulkan.py can be imported. This needs to be a complete path.
+ld_path = os.path.dirname(os.path.abspath(__file__))
+main_path = os.path.abspath(ld_path + "/../")
+sys.path.append(main_path)
+
+import vulkan
+
+def generate_get_proc_addr_check(name):
+    return "    if (!%s || %s[0] != 'v' || %s[1] != 'k')\n" \
+           "        return NULL;" % ((name,) * 3)
+
+class Subcommand(object):
+    def __init__(self, argv):
+        self.argv = argv
+        self.headers = vulkan.headers
+        self.protos = vulkan.protos
+
+    def run(self):
+        print(self.generate())
+
+    def _does_function_create_object(self, proto):
+        out_objs = proto.object_out_params()
+        if proto.name == "ResetFences":
+            return False
+        return out_objs and out_objs[-1] == proto.params[-1]
+
+    def _is_loader_special_case(self, proto):
+        if proto.name in ["GetProcAddr", "EnumeratePhysicalDevices", "EnumerateLayers", "DbgRegisterMsgCallback", "DbgUnregisterMsgCallback", "DbgSetGlobalOption", "DestroyInstance"]:
+            return True
+        return not self.is_dispatchable_object_first_param(proto)
+
+
+    def is_dispatchable_object_first_param(self, proto):
+        in_objs = proto.object_in_params()
+        non_dispatch_objs = []
+        param0 = proto.params[0]
+        return (len(in_objs) > 0)  and (in_objs[0].ty == param0.ty) and (param0.ty not in non_dispatch_objs)
+
+    def generate(self):
+        copyright = self.generate_copyright()
+        header = self.generate_header()
+        body = self.generate_body()
+        footer = self.generate_footer()
+
+        contents = []
+        if copyright:
+            contents.append(copyright)
+        if header:
+            contents.append(header)
+        if body:
+            contents.append(body)
+        if footer:
+            contents.append(footer)
+
+        return "\n\n".join(contents)
+
+    def generate_copyright(self):
+        return """/* THIS FILE IS GENERATED.  DO NOT EDIT. */
+
+/*
+ * Vulkan
+ *
+ * Copyright (C) 2014 LunarG, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included
+ * in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ */"""
+
+    def generate_header(self):
+        return "\n".join(["#include <" + h + ">" for h in self.headers])
+
+    def generate_body(self):
+        pass
+
+    def generate_footer(self):
+        pass
+
+class LoaderEntrypointsSubcommand(Subcommand):
+    def generate_header(self):
+        return "#include \"loader.h\""
+
+    def _generate_object_setup(self, proto):
+        method = "loader_init_dispatch"
+        cond = "res == VK_SUCCESS"
+
+        if "Get" in proto.name:
+            method = "loader_set_dispatch"
+
+        setup = []
+
+        if proto.name == "AllocDescriptorSets":
+            psets = proto.params[-2].name
+            pcount = proto.params[-1].name
+            setup.append("uint32_t i;")
+            setup.append("for (i = 0; i < *%s; i++)" % pcount)
+            setup.append("    %s(%s[i], disp);" % (method, psets))
+        elif proto.name == "GetPhysicalDeviceInfo":
+            ptype = proto.params[-3].name
+            psize = proto.params[-2].name
+            pdata = proto.params[-1].name
+            cond = ("%s == VK_PHYSICAL_DEVICE_INFO_TYPE_DISPLAY_PROPERTIES_WSI && "
+                    "%s && %s" % (ptype, pdata, cond))
+            setup.append("VkDisplayPropertiesWSI *info = %s;" % pdata)
+            setup.append("size_t count = *%s / sizeof(*info), i;" % psize)
+            setup.append("for (i = 0; i < count; i++) {")
+            setup.append("    %s(info[i].display, disp);" % method)
+            setup.append("}")
+        elif proto.name == "GetSwapChainInfoWSI":
+            ptype = proto.params[-3].name
+            psize = proto.params[-2].name
+            pdata = proto.params[-1].name
+            cond = ("%s == VK_SWAP_CHAIN_INFO_TYPE_PERSISTENT_IMAGES_WSI && "
+                    "%s && %s" % (ptype, pdata, cond))
+            setup.append("VkSwapChainImageInfoWSI *info = %s;" % pdata)
+            setup.append("size_t count = *%s / sizeof(*info), i;" % psize)
+            setup.append("for (i = 0; i < count; i++) {")
+            setup.append("    %s(info[i].image, disp);" % method)
+            setup.append("    %s(info[i].memory, disp);" % method)
+            setup.append("}")
+        elif proto.name != "ResetFences":
+            obj_params = proto.object_out_params()
+            for param in obj_params:
+                setup.append("%s(*%s, disp);" % (method, param.name))
+
+        if setup:
+            joined = "\n        ".join(setup)
+            setup = []
+            setup.append("    if (%s) {" % cond)
+            setup.append("        " + joined)
+            setup.append("    }")
+
+        return "\n".join(setup)
+
+    def _generate_loader_dispatch_entrypoints(self, qual=""):
+        if qual:
+            qual += " "
+
+        funcs = []
+        for proto in self.protos:
+            if self._is_loader_special_case(proto):
+                continue
+            func = []
+
+            obj_setup = self._generate_object_setup(proto)
+
+            func.append(qual + proto.c_func(prefix="vk", attr="VKAPI"))
+            func.append("{")
+
+            # declare local variables
+            func.append("    const VkLayerDispatchTable *disp;")
+            if proto.ret != 'void' and obj_setup:
+                func.append("    VkResult res;")
+            func.append("")
+
+            # get dispatch table
+            func.append("    disp = loader_get_dispatch(%s);" %
+                    proto.params[0].name)
+            func.append("")
+
+            # dispatch!
+            dispatch = "disp->%s;" % proto.c_call()
+            if proto.ret == 'void':
+                func.append("    " + dispatch)
+            elif not obj_setup:
+                func.append("    return " + dispatch)
+            else:
+                func.append("    res = " + dispatch)
+                func.append(obj_setup)
+                func.append("")
+                func.append("    return res;")
+
+            func.append("}")
+
+            funcs.append("\n".join(func))
+
+        return "\n\n".join(funcs)
+
+    def generate_body(self):
+        body = [self._generate_loader_dispatch_entrypoints("LOADER_EXPORT")]
+
+        return "\n\n".join(body)
+
+class DispatchTableOpsSubcommand(Subcommand):
+    def run(self):
+        if len(self.argv) != 1:
+            print("DispatchTableOpsSubcommand: <prefix> unspecified")
+            return
+
+        self.prefix = self.argv[0]
+        super().run()
+
+    def generate_header(self):
+        return "\n".join(["#include <vulkan.h>",
+                          "#include <vkLayer.h>",
+                          "#include <string.h>",
+                          "#include \"loader_platform.h\""])
+
+    def _generate_init(self):
+        stmts = []
+        for proto in self.protos:
+            if self.is_dispatchable_object_first_param(proto) or proto.name == "CreateInstance":
+                stmts.append("table->%s = (PFN_vk%s) gpa(gpu, \"vk%s\");" %
+                        (proto.name, proto.name, proto.name))
+            else:
+                stmts.append("table->%s = vk%s; /* non-dispatchable */" %
+                             (proto.name, proto.name))
+
+        func = []
+        func.append("static inline void %s_initialize_dispatch_table(VkLayerDispatchTable *table,"
+                % self.prefix)
+        func.append("%s                                              PFN_vkGetProcAddr gpa,"
+                % (" " * len(self.prefix)))
+        func.append("%s                                              VkPhysicalDevice gpu)"
+                % (" " * len(self.prefix)))
+        func.append("{")
+        func.append("    %s" % "\n    ".join(stmts))
+        func.append("}")
+
+        return "\n".join(func)
+
+    def _generate_lookup(self):
+        lookups = []
+        for proto in self.protos:
+            if self.is_dispatchable_object_first_param(proto):
+                lookups.append("if (!strcmp(name, \"%s\"))" % (proto.name))
+                lookups.append("    return (void *) table->%s;"
+                    % (proto.name))
+
+        func = []
+        func.append("static inline void *%s_lookup_dispatch_table(const VkLayerDispatchTable *table,"
+                % self.prefix)
+        func.append("%s                                           const char *name)"
+                % (" " * len(self.prefix)))
+        func.append("{")
+        func.append(generate_get_proc_addr_check("name"))
+        func.append("")
+        func.append("    name += 2;")
+        func.append("    %s" % "\n    ".join(lookups))
+        func.append("")
+        func.append("    return NULL;")
+        func.append("}")
+
+        return "\n".join(func)
+
+    def generate_body(self):
+        body = [self._generate_init(),
+                self._generate_lookup()]
+
+        return "\n\n".join(body)
+
+class WinDefFileSubcommand(Subcommand):
+    def run(self):
+        library_exports = {
+                "all": [],
+        }
+
+        if len(self.argv) != 2 or self.argv[1] not in library_exports:
+            print("WinDefFileSubcommand: <library-name> {%s}" %
+                    "|".join(library_exports.keys()))
+            return
+
+        self.library = self.argv[0]
+        self.exports = library_exports[self.argv[1]]
+
+        super().run()
+
+    def generate_copyright(self):
+        return """; THIS FILE IS GENERATED.  DO NOT EDIT.
+
+;;;; Begin Copyright Notice ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+; Vulkan
+;
+; Copyright (C) 2015 LunarG, Inc.
+;
+; Permission is hereby granted, free of charge, to any person obtaining a
+; copy of this software and associated documentation files (the "Software"),
+; to deal in the Software without restriction, including without limitation
+; the rights to use, copy, modify, merge, publish, distribute, sublicense,
+; and/or sell copies of the Software, and to permit persons to whom the
+; Software is furnished to do so, subject to the following conditions:
+;
+; The above copyright notice and this permission notice shall be included
+; in all copies or substantial portions of the Software.
+;
+; THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+; IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+; FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+; THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+; LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+; FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+; DEALINGS IN THE SOFTWARE.
+;;;;  End Copyright Notice ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;"""
+
+    def generate_header(self):
+        return "; The following is required on Windows, for exporting symbols from the DLL"
+
+    def generate_body(self):
+        body = []
+
+        body.append("LIBRARY " + self.library)
+        body.append("EXPORTS")
+
+        for proto in self.protos:
+            if self.exports and proto.name not in self.exports:
+                continue
+            body.append("   vk" + proto.name)
+
+        return "\n".join(body)
+
+class LoaderGetProcAddrSubcommand(Subcommand):
+    def run(self):
+        self.prefix = "vk"
+
+        # we could get the list from argv if wanted
+        self.intercepted = [proto.name for proto in self.protos]
+
+        for proto in self.protos:
+            if proto.name == "GetProcAddr":
+                self.gpa = proto
+
+        super().run()
+
+    def generate_header(self):
+        return "\n".join(["#include <string.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))
+
+        special_lookups = []
+        # these functions require special trampoline code beyond just the normal create object trampoline code
+        special_names = ["AllocDescriptorSets", "GetMultiDeviceCompatibility"]
+        for proto in self.protos:
+            if self._is_loader_special_case(proto) or self._does_function_create_object(proto) or proto.name in special_names:
+                special_lookups.append("if (!strcmp(name, \"%s\"))" % proto.name)
+                special_lookups.append("    return (%s) %s%s;" %
+                        (self.gpa.ret, self.prefix, proto.name))
+            else:
+                continue
+        body = []
+        body.append("static inline %s globalGetProcAddr(const char *name)" %
+                self.gpa.ret)
+        body.append("{")
+        body.append(generate_get_proc_addr_check("name"))
+        body.append("")
+        body.append("    name += 2;")
+        body.append("    %s" % "\n    ".join(lookups))
+        body.append("")
+        body.append("    return NULL;")
+        body.append("}")
+        body.append("")
+        body.append("static inline void *loader_non_passthrough_gpa(const char *name)")
+        body.append("{")
+        body.append(generate_get_proc_addr_check("name"))
+        body.append("")
+        body.append("    name += 2;")
+        body.append("    %s" % "\n    ".join(special_lookups))
+        body.append("")
+        body.append("    return NULL;")
+        body.append("}")
+
+        return "\n".join(body)
+
+def main():
+    subcommands = {
+            "loader-entrypoints": LoaderEntrypointsSubcommand,
+            "dispatch-table-ops": DispatchTableOpsSubcommand,
+            "win-def-file": WinDefFileSubcommand,
+            "loader-get-proc-addr": LoaderGetProcAddrSubcommand,
+    }
+
+    if len(sys.argv) < 2 or sys.argv[1] not in subcommands:
+        print("Usage: %s <subcommand> [options]" % sys.argv[0])
+        print
+        print("Available sucommands are: %s" % " ".join(subcommands))
+        exit(1)
+
+    subcmd = subcommands[sys.argv[1]](sys.argv[2:])
+    subcmd.run()
+
+if __name__ == "__main__":
+    main()