build-aux/extract-ofp-errors

   1 #! /usr/bin/python
   2
   3 import sys
   4 import os.path
   5 import re
   6
   7 macros = {}
   8
   9 token = None
  10 line = ""
  11 idRe = "[a-zA-Z_][a-zA-Z_0-9]*"
  12 tokenRe = "#?" + idRe + "|[0-9]+|."
  13 inComment = False
  14 inDirective = False
  15
  16 def getLine():
  17     global line
  18     global lineNumber
  19     line = inputFile.readline()
  20     lineNumber += 1
  21     if line == "":
  22         fatal("unexpected end of input")
  23
  24 def getToken():
  25     global token
  26     global line
  27     global inComment
  28     global inDirective
  29     while True:
  30         line = line.lstrip()
  31         if line != "":
  32             if line.startswith("/*"):
  33                 inComment = True
  34                 line = line[2:]
  35             elif inComment:
  36                 commentEnd = line.find("*/")
  37                 if commentEnd < 0:
  38                     line = ""
  39                 else:
  40                     inComment = False
  41                     line = line[commentEnd + 2:]
  42             else:
  43                 match = re.match(tokenRe, line)
  44                 token = match.group(0)
  45                 line = line[len(token):]
  46                 if token.startswith('#'):
  47                     inDirective = True
  48                 elif token in macros and not inDirective:
  49                     line = macros[token] + line
  50                     continue
  51                 return True
  52         elif inDirective:
  53             token = "$"
  54             inDirective = False
  55             return True
  56         else:
  57             global lineNumber
  58             line = inputFile.readline()
  59             lineNumber += 1
  60             while line.endswith("\\\n"):
  61                 line = line[:-2] + inputFile.readline()
  62                 lineNumber += 1
  63             if line == "":
  64                 if token == None:
  65                     fatal("unexpected end of input")
  66                 token = None
  67                 return False
  68
  69 n_errors = 0
  70 def error(msg):
  71     global n_errors
  72     sys.stderr.write("%s:%d: %s\n" % (fileName, lineNumber, msg))
  73     n_errors += 1
  74
  75 def fatal(msg):
  76     error(msg)
  77     sys.exit(1)
  78
  79 def skipDirective():
  80     getToken()
  81     while token != '$':
  82         getToken()
  83
  84 def isId(s):
  85     return re.match(idRe + "$", s) != None
  86
  87 def forceId():
  88     if not isId(token):
  89         fatal("identifier expected")
  90
  91 def forceInteger():
  92     if not re.match('[0-9]+$', token):
  93         fatal("integer expected")
  94
  95 def match(t):
  96     if token == t:
  97         getToken()
  98         return True
  99     else:
 100         return False
 101
 102 def forceMatch(t):
 103     if not match(t):
 104         fatal("%s expected" % t)
 105
 106 def parseTaggedName():
 107     assert token in ('struct', 'union')
 108     name = token
 109     getToken()
 110     forceId()
 111     name = "%s %s" % (name, token)
 112     getToken()
 113     return name
 114
 115 def print_enum(tag, constants, storage_class):
 116     print ("""
 117 %(storage_class)sconst char *
 118 %(tag)s_to_string(uint16_t value)
 119 {
 120     switch (value) {\
 121 """ % {"tag": tag,
 122        "bufferlen": len(tag) + 32,
 123        "storage_class": storage_class})
 124     for constant in constants:
 125         print ("    case %s: return \"%s\";" % (constant, constant))
 126     print ("""\
 127     }
 128     return NULL;
 129 }\
 130 """ % {"tag": tag})
 131
 132 def usage():
 133     argv0 = os.path.basename(sys.argv[0])
 134     print ('''\
 135 %(argv0)s, for extracting OpenFlow error codes from header files
 136 usage: %(argv0)s FILE [FILE...]
 137
 138 This program reads the header files specified on the command line and
 139 outputs a C source file for translating OpenFlow error codes into
 140 strings, for use as lib/ofp-errors.c in the Open vSwitch source tree.
 141
 142 This program is specialized for reading lib/ofp-errors.h.  It will not
 143 work on arbitrary header files without extensions.\
 144 ''' % {"argv0": argv0})
 145     sys.exit(0)
 146
 147 def extract_ofp_errors(filenames):
 148     error_types = {}
 149
 150     comments = []
 151     names = []
 152     domain = {}
 153     reverse = {}
 154     for domain_name in ("OF1.0", "OF1.1", "OF1.2", "OF1.3",
 155                         "NX1.0", "NX1.1", "NX1.2", "NX1.3"):
 156         domain[domain_name] = {}
 157         reverse[domain_name] = {}
 158
 159     n_errors = 0
 160     expected_errors = {}
 161
 162     global fileName
 163     for fileName in filenames:
 164         global inputFile
 165         global lineNumber
 166         inputFile = open(fileName)
 167         lineNumber = 0
 168
 169         while True:
 170             getLine()
 171             if re.match('enum ofperr', line):
 172                 break
 173
 174         while True:
 175             getLine()
 176             if line.startswith('/*') or not line or line.isspace():
 177                 continue
 178             elif re.match('}', line):
 179                 break
 180
 181             if not line.lstrip().startswith('/*'):
 182                 fatal("unexpected syntax between errors")
 183
 184             comment = line.lstrip()[2:].strip()
 185             while not comment.endswith('*/'):
 186                 getLine()
 187                 if line.startswith('/*') or not line or line.isspace():
 188                     fatal("unexpected syntax within error")
 189                 comment += ' %s' % line.lstrip('* \t').rstrip(' \t\r\n')
 190             comment = comment[:-2].rstrip()
 191
 192             m = re.match('Expected: (.*)\.$', comment)
 193             if m:
 194                 expected_errors[m.group(1)] = (fileName, lineNumber)
 195                 continue
 196
 197             m = re.match('((?:.(?!\.  ))+.)\.  (.*)$', comment)
 198             if not m:
 199                 fatal("unexpected syntax between errors")
 200
 201             dsts, comment = m.groups()
 202
 203             getLine()
 204             m = re.match('\s+(?:OFPERR_((?:OFP|NX)[A-Z0-9_]+))(\s*=\s*OFPERR_OFS)?,',
 205                          line)
 206             if not m:
 207                 fatal("syntax error expecting enum value")
 208
 209             enum = m.group(1)
 210
 211             comments.append(re.sub('\[[^]]*\]', '', comment))
 212             names.append(enum)
 213
 214             for dst in dsts.split(', '):
 215                 m = re.match(r'([A-Z0-9.+]+)\((\d+)(?:,(\d+))?\)$', dst)
 216                 if not m:
 217                     fatal("%s: syntax error in destination" % dst)
 218                 targets = m.group(1)
 219                 type_ = int(m.group(2))
 220                 if m.group(3):
 221                     code = int(m.group(3))
 222                 else:
 223                     code = None
 224
 225                 target_map = {"OF1.0+": ("OF1.0", "OF1.1", "OF1.2", "OF1.3"),
 226                               "OF1.1+": ("OF1.1", "OF1.2", "OF1.3"),
 227                               "OF1.2+": ("OF1.2", "OF1.3"),
 228                               "OF1.3+": ("OF1.3",),
 229                               "OF1.0":  ("OF1.0",),
 230                               "OF1.1":  ("OF1.1",),
 231                               "OF1.2":  ("OF1.2",),
 232                               "OF1.3":  ("OF1.3",),
 233                               "NX1.0+": ("OF1.0", "OF1.1", "OF1.2", "OF1.3"),
 234                               "NX1.1+": ("OF1.1", "OF1.2", "OF1.3"),
 235                               "NX1.2+": ("OF1.2", "OF1.3"),
 236                               "NX1.3+": ("OF1.3",),
 237                               "NX1.0":  ("OF1.0",),
 238                               "NX1.1":  ("OF1.1",),
 239                               "NX1.2":  ("OF1.2",),
 240                               "NX1.3":  ("OF1.3",)}
 241                 if targets not in target_map:
 242                     fatal("%s: unknown error domain" % targets)
 243                 if targets.startswith('NX') and code < 0x100:
 244                     fatal("%s: NX domain code cannot be less than 0x100" % dst)
 245                 if targets.startswith('OF') and code >= 0x100:
 246                     fatal("%s: OF domain code cannot be greater than 0x100"
 247                           % dst)
 248                 for target in target_map[targets]:
 249                     domain[target].setdefault(type_, {})
 250                     if code in domain[target][type_]:
 251                         msg = "%d,%d in %s means both %s and %s" % (
 252                             type_, code, target,
 253                             domain[target][type_][code][0], enum)
 254                         if msg in expected_errors:
 255                             del expected_errors[msg]
 256                         else:
 257                             error("%s: %s." % (dst, msg))
 258                             sys.stderr.write("%s:%d: %s: Here is the location "
 259                                              "of the previous definition.\n"
 260                                              % (domain[target][type_][code][1],
 261                                                 domain[target][type_][code][2],
 262                                                 dst))
 263                     else:
 264                         domain[target][type_][code] = (enum, fileName,
 265                                                        lineNumber)
 266
 267                     if enum in reverse[target]:
 268                         error("%s: %s in %s means both %d,%d and %d,%d." %
 269                               (dst, enum, target,
 270                                reverse[target][enum][0],
 271                                reverse[target][enum][1],
 272                                type_, code))
 273                     reverse[target][enum] = (type_, code)
 274
 275         inputFile.close()
 276
 277     for fn, ln in expected_errors.values():
 278         sys.stderr.write("%s:%d: expected duplicate not used.\n" % (fn, ln))
 279         n_errors += 1
 280
 281     if n_errors:
 282         sys.exit(1)
 283
 284     print ("""\
 285 /* Generated automatically; do not modify!     -*- buffer-read-only: t -*- */
 286
 287 #define OFPERR_N_ERRORS %d
 288
 289 struct ofperr_domain {
 290     const char *name;
 291     uint8_t version;
 292     enum ofperr (*decode)(uint16_t type, uint16_t code);
 293     struct pair errors[OFPERR_N_ERRORS];
 294 };
 295
 296 static const char *error_names[OFPERR_N_ERRORS] = {
 297 %s
 298 };
 299
 300 static const char *error_comments[OFPERR_N_ERRORS] = {
 301 %s
 302 };\
 303 """ % (len(names),
 304        '\n'.join('    "%s",' % name for name in names),
 305        '\n'.join('    "%s",' % re.sub(r'(["\\])', r'\\\1', comment)
 306                  for comment in comments)))
 307
 308     def output_domain(map, name, description, version):
 309         print ("""
 310 static enum ofperr
 311 %s_decode(uint16_t type, uint16_t code)
 312 {
 313     switch ((type << 16) | code) {""" % name)
 314         found = set()
 315         for enum in names:
 316             if enum not in map:
 317                 continue
 318             type_, code = map[enum]
 319             if code is None:
 320                 continue
 321             value = (type_ << 16) | code
 322             if value in found:
 323                 continue
 324             found.add(value)
 325             print ("    case (%d << 16) | %d:" % (type_, code))
 326             print ("        return OFPERR_%s;" % enum)
 327         print ("""\
 328     }
 329
 330     return 0;
 331 }""")
 332
 333         print ("""
 334 static const struct ofperr_domain %s = {
 335     "%s",
 336     %d,
 337     %s_decode,
 338     {""" % (name, description, version, name))
 339         for enum in names:
 340             if enum in map:
 341                 type_, code = map[enum]
 342                 if code == None:
 343                     code = -1
 344             else:
 345                 type_ = code = -1
 346             print ("        { %2d, %3d }, /* %s */" % (type_, code, enum))
 347         print ("""\
 348     },
 349 };""")
 350
 351     output_domain(reverse["OF1.0"], "ofperr_of10", "OpenFlow 1.0", 0x01)
 352     output_domain(reverse["OF1.1"], "ofperr_of11", "OpenFlow 1.1", 0x02)
 353     output_domain(reverse["OF1.2"], "ofperr_of12", "OpenFlow 1.2", 0x03)
 354     output_domain(reverse["OF1.3"], "ofperr_of13", "OpenFlow 1.3", 0x04)
 355
 356 if __name__ == '__main__':
 357     if '--help' in sys.argv:
 358         usage()
 359     elif len(sys.argv) < 2:
 360         sys.stderr.write("at least one non-option argument required; "
 361                          "use --help for help\n")
 362         sys.exit(1)
 363     else:
 364         extract_ofp_errors(sys.argv[1:])