epan/wslua/make-taps.py

   1 #!/usr/bin/env python3
   2 #
   3 # make-taps.py
   4 #
   5 # By Gerald Combs <gerald@wireshark.org>
   6 # Based on make-taps.pl by Luis E. Garcia Onatnon <luis.ontanon@gmail.com>
   7 #
   8 # Wireshark - Network traffic analyzer
   9 # By Gerald Combs <gerald@wireshark.org>
  10 # Copyright 1998 Gerald Combs
  11 #
  12 # SPDX-License-Identifier: GPL-2.0-or-later
  13 '''\
  14 Extract structs from C headers to generate a function that pushes a lua table
  15 into the stack containing the elements of the struct.
  16 '''
  17
  18 import argparse
  19 import configparser
  20 import os
  21 import re
  22 import sys
  23
  24
  25 this_dir = os.path.dirname(__file__)
  26
  27
  28 def get_tap_info(tap_name, header_file, struct_name, enum_types):
  29     code = f'#include "{header_file}"\n'
  30     doc = f'Tap: {tap_name}\n'
  31     enums = {}
  32     buf = ''
  33
  34     types = {
  35         'gchar[]': 'lua_pushstring(L,(const char*)v->STR);',
  36         'gchar*': 'lua_pushstring(L,(const char*)v->STR);',
  37         'guint': 'lua_pushinteger(L,(lua_Integer)v->STR);',
  38         'guint8': 'lua_pushinteger(L,(lua_Integer)v->STR);',
  39         'guint16': 'lua_pushinteger(L,(lua_Integer)v->STR);',
  40         'guint32': 'lua_pushinteger(L,(lua_Integer)v->STR);',
  41         'gint': 'lua_pushinteger(L,(lua_Integer)v->STR);',
  42         'gint8': 'lua_pushinteger(L,(lua_Integer)v->STR);',
  43         'gint16': 'lua_pushinteger(L,(lua_Integer)v->STR);',
  44         'gint32': 'lua_pushinteger(L,(lua_Integer)v->STR);',
  45         'gboolean': 'lua_pushboolean(L,(int)v->STR);',
  46         'char[]': 'lua_pushstring(L,(const char*)v->STR);',
  47         'char*': 'lua_pushstring(L,(const char*)v->STR);',
  48         'unsigned': 'lua_pushinteger(L,(lua_Integer)v->STR);',
  49         'uint8_t': 'lua_pushinteger(L,(lua_Integer)v->STR);',
  50         'uint16_t': 'lua_pushinteger(L,(lua_Integer)v->STR);',
  51         'uint32_t': 'lua_pushinteger(L,(lua_Integer)v->STR);',
  52         'int': 'lua_pushinteger(L,(lua_Integer)v->STR);',
  53         'int8_t': 'lua_pushinteger(L,(lua_Integer)v->STR);',
  54         'int16_t': 'lua_pushinteger(L,(lua_Integer)v->STR);',
  55         'int32': 'lua_pushinteger(L,(lua_Integer)v->STR);',
  56         'bool': 'lua_pushboolean(L,(int)v->STR);',
  57         'address': '{ Address a = (Address)g_malloc(sizeof(address)); copy_address(a, &(v->STR)); pushAddress(L,a); }',
  58         'address*': '{ Address a = (Address)g_malloc(sizeof(address)); copy_address(a, v->STR); pushAddress(L,a); }',
  59         'nstime_t': 'lua_pushnumber(L,(lua_Number)nstime_to_sec(&(v->STR)));',
  60         'nstime_t*': 'lua_pushnumber(L,(lua_Number)nstime_to_sec(v->STR));',
  61     }
  62
  63     comments = {
  64         'gchar[]': 'string',
  65         'gchar*': 'string',
  66         'guint': 'number',
  67         'guint8': 'number',
  68         'guint16': 'number',
  69         'guint32': 'number',
  70         'gint': 'number',
  71         'gint8': 'number',
  72         'gint16': 'number',
  73         'gint32': 'number',
  74         'gboolean': 'boolean',
  75         'char[]': 'string',
  76         'char*': 'string',
  77         'unsigned': 'number',
  78         'uint8_t': 'number',
  79         'uint16_t': 'number',
  80         'uint32_t': 'number',
  81         'int': 'number',
  82         'int8_t': 'number',
  83         'int16_t': 'number',
  84         'int32_t': 'number',
  85         'bool': 'boolean',
  86         'address': 'Address',
  87         'address*': 'Address',
  88         'nstime_t': 'number (seconds, since 1-1-1970 if absolute)',
  89         'nstime_t*': 'number (seconds, since 1-1-1970 if absolute)',
  90     }
  91
  92     with open(os.path.join(this_dir, header_file), encoding='utf-8') as header_f:
  93         for line in header_f:
  94             # Remove comments
  95             line = re.sub(r'\/\*.*?\*/', '', line)
  96             line = re.sub(r'//.*', '', line)
  97             buf += line
  98
  99     for enum in enum_types:
 100         m = re.search(fr'typedef\s+enum[^{{]*{{([^}}]*)}}[\s\n]*{enum}[\s\n]*;', buf, flags=re.DOTALL)
 101         if m:
 102             types[enum] = f'lua_pushinteger(L,(lua_Integer)v->STR); /* {enum} */'
 103             econsts = m.group(1).splitlines()
 104             econsts = [re.sub(r'\s+', '', item) for item in econsts]
 105             econsts = [re.sub(',', '', item) for item in econsts]
 106             econsts = [item for item in econsts if item]
 107             enums[enum] = econsts
 108             ebody = '|'.join(econsts)
 109             comments[enum] = f'{enum}: {{ {ebody} }}'
 110
 111     m = re.search(fr'typedef\s+struct.*?{{([^}}]*)}}[\s\n]*({struct_name})[\s\n]*;', buf, flags=re.DOTALL)
 112     if not m:
 113         sys.stderr.write(f'could not find typedef {struct_name} in {header_file}')
 114         sys.exit(1)
 115
 116     body = m.group(1)
 117
 118     elems = {}
 119
 120     for line in body.splitlines():
 121         k = None
 122         v = None
 123
 124         m = re.search(r'\s*(.*?)([\w\d_]+)\s*\[\s*\d+\s*\]\s*;', line)
 125         if m:
 126             k = m.group(2)
 127             v = m.group(1)
 128             v += '[]'
 129
 130         m = re.search(r'\s*(.*?)([\w\d_]+)\s*;', line)
 131         if m:
 132             k = m.group(2)
 133             v = m.group(1)
 134
 135         if v and k:
 136             v = re.sub(r'const ', '', v)
 137             v = re.sub(r'\s+', '', v)
 138             elems[k] = v
 139
 140     code += f'static void wslua_{tap_name}_to_table(lua_State* L, const void* p) {{\n\tconst {struct_name}* v;\n\n\tv = (const {struct_name}*)p;\n\tlua_newtable(L);\n\n'
 141
 142     for el in sorted(elems):
 143         try:
 144             fmt = types[elems[el]]
 145             code += f'\tlua_pushstring(L,\"{el}\");\n\t'
 146             lua_type = re.sub(r'\bSTR\b', el, fmt)
 147             code += lua_type
 148             code += '\n\tlua_settable(L,-3);\n'
 149             doc += f'\t{el}: {comments[elems[el]]}\n'
 150         except KeyError:
 151             pass
 152
 153     code += "}\n\n"
 154     doc += "\n"
 155
 156     return (code, doc, enums)
 157
 158
 159 def main():
 160     parser = argparse.ArgumentParser(description="Generate bindings required for Lua taps.")
 161     parser.add_argument("out_c", metavar='C file', help="output C file")
 162     parser.add_argument("out_doc", metavar='documentation file', help="output text file")
 163     args = parser.parse_args()
 164
 165     tap_config = configparser.ConfigParser()
 166     tap_config.read(os.path.join(this_dir, 'taps.ini'))
 167
 168     enums = {}
 169     c_body = '''\
 170 /*  This file is autogenerated from ./taps by ./make-taps.py */
 171 /* DO NOT EDIT! */
 172
 173 #include "config.h"
 174
 175 #include "wslua.h"
 176
 177 #include <wsutil/nstime.h>
 178
 179 '''
 180     doc_body = '\n'
 181
 182     for tap_name in tap_config.sections():
 183         tap_d = tap_config[tap_name]
 184         enum_types = []
 185         if 'enum_types' in tap_d.keys():
 186             enum_types = tap_d['enum_types'].split(' ')
 187         (code, doc, file_enums) = get_tap_info(tap_name, tap_d['header_file'], tap_d['struct_name'], enum_types)
 188         c_body += code
 189         doc_body += doc
 190         enums.update(file_enums)
 191
 192     c_body += 'static tappable_t tappables[] =  {\n'
 193     for tap_name in sorted(tap_config.sections()):
 194         c_body += f'\t{{"{tap_name}", wslua_{tap_name}_to_table }},\n'
 195     c_body += '''\
 196         {"frame",NULL},
 197         {NULL,NULL}
 198 };
 199 '''
 200
 201     c_body += '\nint wslua_set_tap_enums(lua_State* L) {\n'
 202     for enum in sorted(enums):
 203         c_body += f'\n\t/*\n\t * {enum}\n\t */\n\tlua_newtable(L);\n'
 204         for econst in enums[enum]:
 205             c_body += f'''\
 206         lua_pushinteger(L,(lua_Integer){econst});
 207         lua_setglobal(L,"{econst}");
 208         lua_pushinteger(L,(lua_Integer){econst});
 209         lua_pushstring(L,"{econst}");
 210         lua_settable(L,-3);
 211 '''
 212         c_body += f'\tlua_setglobal(L,\"{enum}\");\n'
 213     c_body += '\treturn 0;\n}\n'
 214
 215     c_body += '''\
 216
 217
 218 tap_extractor_t wslua_get_tap_extractor(const gchar* name) {
 219         tappable_t* t;
 220         for(t = tappables; t->name; t++ ) {
 221                 if (g_str_equal(t->name,name)) return t->extractor;
 222         }
 223
 224         return NULL;
 225 }
 226 '''
 227
 228     with open(args.out_c, mode='w', encoding='utf-8') as out_c_f:
 229         out_c_f.write(c_body)
 230
 231     with open(args.out_doc, mode='w', encoding='utf-8') as out_doc_f:
 232         out_doc_f.write(doc_body)
 233
 234 if __name__ == '__main__':
 235     main()