1 files changed, 184 insertions, 0 deletions
diff --git a/tools/codegen/core/gen_settings_ids.py b/tools/codegen/core/gen_settings_ids.py
new file mode 100755
index 0000000000..a986138337
--- /dev/null
+++ b/tools/codegen/core/gen_settings_ids.py
@@ -0,0 +1,184 @@
+#!/usr/bin/env python2.7
+
+# Copyright 2017, Google Inc.
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met:
+#
+#     * Redistributions of source code must retain the above copyright
+# notice, this list of conditions and the following disclaimer.
+#     * Redistributions in binary form must reproduce the above
+# copyright notice, this list of conditions and the following disclaimer
+# in the documentation and/or other materials provided with the
+# distribution.
+#     * Neither the name of Google Inc. nor the names of its
+# contributors may be used to endorse or promote products derived from
+# this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+import collections
+import perfection
+import sys
+
+_MAX_HEADER_LIST_SIZE = 16 * 1024 * 1024
+
+Setting = collections.namedtuple('Setting', 'id default min max on_error')
+OnError = collections.namedtuple('OnError', 'behavior code')
+clamp_invalid_value = OnError('CLAMP_INVALID_VALUE', 'PROTOCOL_ERROR')
+disconnect_on_invalid_value = lambda e: OnError('DISCONNECT_ON_INVALID_VALUE', e)
+DecoratedSetting = collections.namedtuple('DecoratedSetting', 'enum name setting')
+
+_SETTINGS = {
+  'HEADER_TABLE_SIZE': Setting(1, 4096, 0, 0xffffffff, clamp_invalid_value),
+  'ENABLE_PUSH': Setting(2, 1, 0, 1, disconnect_on_invalid_value('PROTOCOL_ERROR')),
+  'MAX_CONCURRENT_STREAMS': Setting(3, 0xffffffff, 0, 0xffffffff, disconnect_on_invalid_value('PROTOCOL_ERROR')),
+  'INITIAL_WINDOW_SIZE': Setting(4, 65535, 0, 0x7fffffff, disconnect_on_invalid_value('FLOW_CONTROL_ERROR')),
+  'MAX_FRAME_SIZE': Setting(5, 16384, 16384, 16777215, disconnect_on_invalid_value('PROTOCOL_ERROR')),
+  'MAX_HEADER_LIST_SIZE': Setting(6, _MAX_HEADER_LIST_SIZE, 0, _MAX_HEADER_LIST_SIZE, clamp_invalid_value),
+  'GRPC_ALLOW_TRUE_BINARY_METADATA': Setting(0xfe03, 0, 0, 1, clamp_invalid_value),
+}
+
+H = open('src/core/ext/transport/chttp2/transport/http2_settings.h', 'w')
+C = open('src/core/ext/transport/chttp2/transport/http2_settings.c', 'w')
+
+# utility: print a big comment block into a set of files
+def put_banner(files, banner):
+  for f in files:
+    print >>f, '/*'
+    for line in banner:
+      print >>f, ' * %s' % line
+    print >>f, ' */'
+    print >>f
+
+# copy-paste copyright notice from this file
+with open(sys.argv[0]) as my_source:
+  copyright = []
+  for line in my_source:
+    if line[0] != '#': break
+  for line in my_source:
+    if line[0] == '#':
+      copyright.append(line)
+      break
+  for line in my_source:
+    if line[0] != '#':
+      break
+    copyright.append(line)
+  put_banner([H,C], [line[2:].rstrip() for line in copyright])
+
+put_banner([H,C], ["Automatically generated by tools/codegen/core/gen_settings_ids.py"])
+
+print >>H, "#ifndef GRPC_CORE_EXT_TRANSPORT_CHTTP2_TRANSPORT_HTTP2_SETTINGS_H"
+print >>H, "#define GRPC_CORE_EXT_TRANSPORT_CHTTP2_TRANSPORT_HTTP2_SETTINGS_H"
+print >>H
+print >>H, "#include <stdint.h>"
+print >>H, "#include <stdbool.h>"
+print >>H
+
+print >>C, "#include \"src/core/ext/transport/chttp2/transport/http2_settings.h\""
+print >>C
+print >>C, "#include <grpc/support/useful.h>"
+print >>C, "#include \"src/core/lib/transport/http2_errors.h\""
+print >>C
+
+p = perfection.hash_parameters(sorted(x.id for x in _SETTINGS.values()))
+print p
+
+def hash(i):
+  i += p.offset
+  x = i % p.t
+  y = i / p.t
+  return x + p.r[y]
+
+decorated_settings = [DecoratedSetting(hash(setting.id), name, setting)
+                      for name, setting in _SETTINGS.iteritems()]
+
+print >>H, 'typedef enum {'
+for decorated_setting in sorted(decorated_settings):
+  print >>H, '  GRPC_CHTTP2_SETTINGS_%s = %d, /* wire id %d */' % (
+      decorated_setting.name, decorated_setting.enum, decorated_setting.setting.id)
+print >>H, '} grpc_chttp2_setting_id;'
+print >>H
+print >>H, '#define GRPC_CHTTP2_NUM_SETTINGS %d' % (max(x.enum for x in decorated_settings) + 1)
+
+print >>H, 'extern const uint16_t grpc_setting_id_to_wire_id[];'
+print >>C, 'const uint16_t grpc_setting_id_to_wire_id[] = {%s};' % ','.join(
+    '%d' % s for s in p.slots)
+print >>H
+print >>H, "bool grpc_wire_id_to_setting_id(uint32_t wire_id, grpc_chttp2_setting_id *out);"
+cgargs = {
+      'r': ','.join('%d' % (r if r is not None else 0) for r in p.r),
+      't': p.t,
+      'offset': abs(p.offset),
+      'offset_sign': '+' if p.offset > 0 else '-'
+  }
+print >>C, """
+bool grpc_wire_id_to_setting_id(uint32_t wire_id, grpc_chttp2_setting_id *out) {
+  uint32_t i = wire_id %(offset_sign)s %(offset)d;
+  uint32_t x = i %% %(t)d;
+  uint32_t y = i / %(t)d;
+  uint32_t h = x;
+  switch (y) {
+""" % cgargs
+for i, r in enumerate(p.r):
+  if not r: continue
+  if r < 0: print >>C, 'case %d: h -= %d; break;' % (i, -r)
+  else: print >>C, 'case %d: h += %d; break;' % (i, r)
+print >>C, """
+  }
+  *out = (grpc_chttp2_setting_id)h;
+  return h < GPR_ARRAY_SIZE(grpc_setting_id_to_wire_id) && grpc_setting_id_to_wire_id[h] == wire_id;
+}
+""" % cgargs
+
+print >>H, """
+typedef enum {
+  GRPC_CHTTP2_CLAMP_INVALID_VALUE,
+  GRPC_CHTTP2_DISCONNECT_ON_INVALID_VALUE
+} grpc_chttp2_invalid_value_behavior;
+
+typedef struct {
+  const char *name;
+  uint32_t default_value;
+  uint32_t min_value;
+  uint32_t max_value;
+  grpc_chttp2_invalid_value_behavior invalid_value_behavior;
+  uint32_t error_value;
+} grpc_chttp2_setting_parameters;
+
+extern const grpc_chttp2_setting_parameters grpc_chttp2_settings_parameters[GRPC_CHTTP2_NUM_SETTINGS];
+"""
+print >>C, "const grpc_chttp2_setting_parameters grpc_chttp2_settings_parameters[GRPC_CHTTP2_NUM_SETTINGS] = {"
+i = 0
+for decorated_setting in sorted(decorated_settings):
+  while i < decorated_setting.enum:
+    print >>C, "{NULL, 0, 0, 0, GRPC_CHTTP2_DISCONNECT_ON_INVALID_VALUE, GRPC_HTTP2_PROTOCOL_ERROR},"
+    i += 1
+  print >>C, "{\"%s\", %du, %du, %du, GRPC_CHTTP2_%s, GRPC_HTTP2_%s}," % (
+    decorated_setting.name,
+    decorated_setting.setting.default,
+    decorated_setting.setting.min,
+    decorated_setting.setting.max,
+    decorated_setting.setting.on_error.behavior,
+    decorated_setting.setting.on_error.code,
+  )
+  i += 1
+print >>C, "};"
+
+print >>H
+print >>H, "#endif /* GRPC_CORE_EXT_TRANSPORT_CHTTP2_TRANSPORT_HTTP2_SETTINGS_H */"
+
+H.close()
+C.close()