dtrace.in

   1 #!@preferred_python@
   2 # vim: et sta sts=4 sw=4 ts=8
   3
   4 # This handles the systemtap equivalent of
   5 # $(DTRACE) $(DTRACEFLAGS) -G -s $^ -o $@
   6 # $(DTRACE) $(DTRACEFLAGS) -h -s $^ -o $@
   7 # which is a step that builds DTrace provider and probe definitions
   8
   9 # Copyright (C) 2009-2018 Red Hat Inc.
  10 #
  11 # This file is part of systemtap, and is free software.  You can
  12 # redistribute it and/or modify it under the terms of the GNU General
  13 # Public License (GPL); either version 2, or (at your option) any
  14 # later version.
  15
  16 # ignore line too long, missing docstring, method could be a function,
  17 #        too many public methods
  18 # pylint: disable=C0301
  19 # pylint: disable=C0111
  20 # pylint: disable=R0201
  21 # pylint: disable=R0904
  22
  23 import os
  24 import sys
  25 from shlex import split
  26 from subprocess import call
  27 from tempfile import mkstemp
  28 try:
  29     from pyparsing import alphas, cStyleComment, delimitedList, Group, \
  30         Keyword, lineno, Literal, nestedExpr, nums, oneOf, OneOrMore, \
  31         Optional, ParseException, ParserElement, restOfLine, restOfLine, \
  32         Suppress, SkipTo, Word, ZeroOrMore
  33     HAVE_PYP = True
  34 except ImportError:
  35     HAVE_PYP = False
  36
  37
  38 # Common file creation methods for pyparsing and string pattern matching
  39
  40 class _HeaderCreator(object):
  41     def init_semaphores(self, fdesc):
  42         # dummy declaration just to make the object file non-empty
  43         fdesc.write("/* Generated by the Systemtap dtrace wrapper */\n\n")
  44         fdesc.write("static void __dtrace (void) __attribute__((unused));\n")
  45         fdesc.write("static void __dtrace (void) {}\n")
  46         fdesc.write("\n#include <sys/sdt.h>\n\n")
  47
  48     def init_probes(self, fdesc):
  49         fdesc.write("/* Generated by the Systemtap dtrace wrapper */\n\n")
  50         fdesc.write("\n#define _SDT_HAS_SEMAPHORES 1\n\n")
  51         fdesc.write("\n#define STAP_HAS_SEMAPHORES 1 /* deprecated */\n\n")
  52         fdesc.write("\n#include <sys/sdt.h>\n\n")
  53
  54     def add_semaphore(self, this_provider, this_probe):
  55         # NB: unsigned short is fixed in ABI
  56         semaphores_def = '\n#if defined STAP_SDT_V1\n'
  57         semaphores_def += '#define %s_%s_semaphore %s_semaphore\n' % \
  58                           (this_provider, this_probe, this_probe)
  59         semaphores_def += '#endif\n'
  60         semaphores_def += '#if defined STAP_SDT_V1 || defined STAP_SDT_V2 \n'
  61         semaphores_def += "__extension__ unsigned short %s_%s_semaphore __attribute__ ((unused)) __attribute__ ((section (\".probes\")));\n" % \
  62             (this_provider, this_probe)
  63         semaphores_def += '#else\n'
  64         semaphores_def += "__extension__ unsigned short %s_%s_semaphore __attribute__ ((unused)) __attribute__ ((section (\".probes\"))) __attribute__ ((visibility (\"hidden\")));\n" % \
  65             (this_provider, this_probe)
  66         semaphores_def += '#endif\n'
  67         return semaphores_def
  68
  69     def add_probe(self, this_provider, this_probe, args):
  70         stap_str = ""
  71         this_probe_canon = this_provider.upper() + "_" + this_probe.replace("__", "_").upper()
  72         define_str = "#define %s(" % (this_probe_canon)
  73         comment_str = "/* %s (" % (this_probe_canon)
  74
  75         if len(args) == 0:
  76             stap_str += "DTRACE_PROBE ("
  77         else:
  78             stap_str += "DTRACE_PROBE%d (" % len(args)
  79         stap_str += "%s, %s" % (this_provider, this_probe)
  80         i = 0
  81         while i < len(args):
  82             if i != 0:
  83                 define_str += ", "
  84                 comment_str += ","
  85             define_str = define_str + "arg%s" % (i + 1)
  86             stap_str = stap_str + ", arg%s" % (i + 1)
  87             for argi in args[i]:
  88                 if len(argi) > 0:
  89                     comment_str += " %s" % argi
  90             i += 1
  91         stap_str += ")"
  92         comment_str += " ) */"
  93         define_str += ") \\\n"
  94         probe_def = '%s\n' % (comment_str)
  95         probe_def += ('#if defined STAP_SDT_V1\n')
  96         probe_def += ('#define %s_ENABLED() __builtin_expect (%s_semaphore, 0)\n' % \
  97                       (this_probe_canon, this_probe))
  98         probe_def += ('#define %s_%s_semaphore %s_semaphore\n' % \
  99                       (this_provider, this_probe, this_probe))
 100         probe_def += ('#else\n')
 101         probe_def += ('#define %s_ENABLED() __builtin_expect (%s_%s_semaphore, 0)\n' % \
 102                       (this_probe_canon, this_provider, this_probe))
 103         probe_def += ('#endif\n')
 104         # NB: unsigned short is fixed in ABI
 105         probe_def += ("__extension__ extern unsigned short %s_%s_semaphore __attribute__ ((unused)) __attribute__ ((section (\".probes\")));\n" % \
 106                       (this_provider, this_probe))
 107         probe_def += (define_str + stap_str + "\n\n")
 108         return probe_def
 109
 110 # Parse using pyparsing if it is available
 111
 112 class _PypProvider(_HeaderCreator):
 113     def __init__(self):
 114         self.ast = []
 115         self.bnf = None
 116         self.dtrace_statements = None
 117
 118     def dtrace_bnf(self):
 119         self.current_probe = ""
 120         if self.dtrace_statements is not None:
 121             return
 122         ParserElement.setDefaultWhitespaceChars(' \f\r\n\t\v')
 123         ident = Word(alphas+"_", alphas+nums+"_$")
 124         probe_ident = Word(alphas+nums+"_$")
 125         semi = Literal(";").suppress()
 126         integer = Word( nums )
 127         lbrace = Literal("{").suppress()
 128         rbrace = Literal("}").suppress()
 129         type_name = ident
 130         varname = ident
 131         PROBE = Keyword("probe")
 132         PROVIDER = Keyword("provider")
 133         array_size = integer | ident
 134         varname_spec = varname + Optional("[" + array_size + "]")
 135         struct_decl = Group(oneOf("struct union") + varname + Suppress(nestedExpr('{','}')) + semi)
 136         enum_decl = Group("enum" + varname + Suppress(nestedExpr('{','}')) + semi)
 137         member_decl = Group((Optional(oneOf("struct unsigned const")) + type_name + Optional(Keyword("const")))
 138                             + Optional(Word("*"), default="") + Optional(varname_spec))
 139         struct_typedef = Group(Literal("typedef") + Literal("struct") + varname
 140                                + Suppress(nestedExpr('{','}'))) + Optional(varname) + semi
 141         typedef = ZeroOrMore("typedef" + (member_decl)) + semi
 142         decls = OneOrMore(struct_typedef | struct_decl | typedef | enum_decl)
 143         def memoize_probe(instring, loc, tokens):
 144             self.current_probe = tokens[0][1]
 145             self.current_lineno = lineno(loc,instring)
 146         probe_decl = Group(PROBE + probe_ident + "(" + Optional(Group(delimitedList(member_decl))) + ")" + Optional(Group(Literal(":") + "(" + Optional(Group(delimitedList(member_decl))) + ")")) + Optional(semi))
 147         probe_decl.setParseAction(memoize_probe)
 148         probe_decls = OneOrMore(probe_decl)
 149
 150         provider_decl = (PROVIDER + Optional(ident)
 151                          + lbrace + Group(probe_decls) + rbrace + Optional(semi))
 152         dtrace_statement = Group (SkipTo("provider", include=False) + provider_decl)
 153         self.dtrace_statements = ZeroOrMore(dtrace_statement)
 154
 155         cplusplus_linecomment = Literal("//") + restOfLine
 156         cpp_linecomment = Literal("#") + restOfLine
 157
 158         self.dtrace_statements.ignore(cStyleComment)
 159         self.dtrace_statements.ignore(cplusplus_linecomment)
 160         self.dtrace_statements.ignore(cpp_linecomment)
 161
 162         self.bnf = self.dtrace_statements
 163
 164     def semaphore_write(self, fdesc):
 165         semaphores_def = ""
 166         self.init_semaphores(fdesc)
 167         for asti in self.ast:
 168             if len(asti) == 0:
 169                 continue
 170             # ignore SkipTo token
 171             if asti[0] != "provider":
 172                 del asti[0]
 173             if asti[0] == "provider":
 174                 # list of probes
 175                 for prb in asti[2]:
 176                     semaphores_def += self.add_semaphore(asti[1], prb[1])
 177         fdesc.write(semaphores_def)
 178
 179
 180     def probe_write(self, provider, header):
 181         hdr = open(header, mode='w')
 182         self.init_probes(hdr)
 183         self.dtrace_bnf()
 184         try:
 185             try:
 186                 self.ast = self.bnf.parseFile(provider, parseAll=True).asList()
 187             except TypeError:
 188                 # pyparsing-1.5.0 does not support parseAll
 189                 self.ast = self.bnf.parseFile(provider).asList()
 190         except ParseException:
 191             err = sys.exc_info()[1]
 192             if len(self.current_probe):
 193                 print("Warning: %s:%s:%d: syntax error near:\nprobe %s\n" % (sys.argv[0], provider, self.current_lineno, self.current_probe))
 194             else:
 195                 print("Warning: %s:%s:%d syntax error near:\n%s\n" % (sys.argv[0], provider, err.lineno, err.line))
 196             raise err
 197
 198         probes_def = ""
 199         for asti in self.ast:
 200             if len(asti) == 0:
 201                 continue
 202             # ignore SkipTo token
 203             if asti[0] != "provider":
 204                 del asti[0]
 205             if asti[0] == "provider":
 206                 # list of probes
 207                 for prb in asti[2]:
 208                     if prb[3] == ')': # No parsed argument list
 209                         alist = []
 210                     else:
 211                         alist = prb[3]
 212                     probes_def += self.add_probe(asti[1], prb[1], alist)
 213         hdr.write(probes_def)
 214         hdr.close()
 215
 216
 217 # Parse using regular expressions if pyparsing is not available
 218
 219 class _ReProvider(_HeaderCreator):
 220     def __init__(self):
 221         self.semaphores_def = "\n"
 222         self.provider = []
 223
 224     def __semaphore_append(self, this_probe):
 225         self.semaphores_def += self.add_semaphore(self.provider, this_probe)
 226
 227     def semaphore_write(self, fdesc):
 228         self.init_semaphores(fdesc)
 229         fdesc.write(self.semaphores_def)
 230
 231     def probe_write(self, provider, header):
 232         have_provider = False
 233         fdesc = open(provider)
 234         hdr = open(header, mode='w')
 235         self.init_probes(hdr)
 236         in_comment = False
 237         probes_def = ""
 238         while True:
 239             line = fdesc.readline()
 240             if line == "":
 241                 break
 242             if line.find("/*") != -1:
 243                 in_comment = True
 244             if line.find("*/") != -1:
 245                 in_comment = False
 246                 continue
 247             if in_comment:
 248                 continue
 249             if line.find("provider") != -1:
 250                 tokens = line.split()
 251                 have_provider = True
 252                 self.provider = tokens[1]
 253             elif have_provider and line.find("probe ") != -1:
 254                 while line.find(")") < 0:
 255                     line += fdesc.readline()
 256                 this_probe = line[line.find("probe ")+5:line.find("(")].strip()
 257                 argstr = (line[line.find("(")+1:line.find(")")])
 258                 arg = ""
 259                 i = 0
 260                 args = []
 261                 self.__semaphore_append(this_probe)
 262                 while i < len(argstr):
 263                     if argstr[i:i+1] == ",":
 264                         args.append(arg.split())
 265                         arg = ""
 266                     else:
 267                         arg = arg + argstr[i]
 268                     i += 1
 269                 if len(arg) > 0:
 270                     args.append(arg.split())
 271                 probes_def += self.add_probe(self.provider, this_probe, args)
 272             elif line.find("}") != -1 and have_provider:
 273                 have_provider = False
 274         hdr.write(probes_def)
 275         hdr.close()
 276
 277
 278 def usage():
 279     print("Usage " + sys.argv[0] + " [--help] [-h | -G] [-C [-I<Path>]] -s File.d [-o <File>]")
 280
 281
 282 def dtrace_help():
 283     usage()
 284     print("Where -h builds a systemtap header file from the .d file")
 285     print("      -C when used with -h, also run cpp preprocessor")
 286     print("      -o specifies an explicit output file name,")
 287     print("         the default for -G is file.o and -h is file.h")
 288     print("      -I when running cpp pass through this -I include Path")
 289     print("      -s specifies the name of the .d input file")
 290     print("      -G builds a stub file.o from file.d,")
 291     print("         which is required by some packages that use dtrace.")
 292     sys.exit(1)
 293
 294
 295 ########################################################################
 296 # main
 297 ########################################################################
 298
 299 def main():
 300     if len(sys.argv) < 2:
 301         usage()
 302         return 1
 303
 304     global HAVE_PYP
 305     i = 1
 306     build_header = False
 307     build_source = False
 308     keep_temps = False
 309     use_cpp = False
 310     suffix = ""
 311     filename = ""
 312     s_filename = ""
 313     includes = []
 314     defines = []
 315     ignore_options = ["-64", "-32", "-fpic", "-fPIC"]
 316     ignore_options2 = ["-x"] # with parameter
 317
 318     while i < len(sys.argv):
 319         if sys.argv[i] == "-o":
 320             i += 1
 321             filename = sys.argv[i]
 322         elif sys.argv[i] == "-s":
 323             i += 1
 324             s_filename = sys.argv[i]
 325         elif sys.argv[i] == "-C":
 326             use_cpp = True
 327         elif sys.argv[i].startswith("-D"):
 328             defines.append(sys.argv[i])
 329         elif sys.argv[i] == "-h":
 330             build_header = True
 331             suffix = ".h"
 332         elif sys.argv[i].startswith("-I"):
 333             includes.append(sys.argv[i])
 334         elif sys.argv[i] == "-G":
 335             build_source = True
 336             suffix = ".o"
 337         elif sys.argv[i] == "-k":
 338             keep_temps = True
 339         elif sys.argv[i] == "--no-pyparsing":
 340             HAVE_PYP = False
 341         elif sys.argv[i] == "--types":
 342             print(sys.argv[0] + ": note: obsolete option --types used")
 343         elif sys.argv[i] in ignore_options:
 344             pass                # dtrace users sometimes pass these flags
 345         elif sys.argv[i] in ignore_options2:
 346             i += 1
 347             pass                # dtrace users sometimes pass these flags
 348         elif sys.argv[i] == "--help":
 349             dtrace_help()
 350         elif sys.argv[i][0] == "-":
 351             print(sys.argv[0], "invalid option", sys.argv[i])
 352             usage()
 353             return 1
 354         i += 1
 355     if not build_header and not build_source:
 356         usage()
 357         return 1
 358
 359     if s_filename != "" and use_cpp:
 360         (ignore, fname) = mkstemp(suffix=".d")
 361         cpp = os.environ.get("CPP", "cpp")
 362         retcode = call(split(cpp) + includes + defines + [s_filename, fname])
 363         if retcode != 0:
 364             print("\"cpp includes s_filename\" failed")
 365             usage()
 366             return 1
 367         s_filename = fname
 368     if filename == "":
 369         if s_filename != "":
 370             (filename, ignore) = os.path.splitext(s_filename)
 371             filename = os.path.basename(filename)
 372         else:
 373             usage()
 374             return 1
 375     else:
 376         suffix = ""
 377
 378     if build_header:
 379         if HAVE_PYP:
 380             providers = _PypProvider()
 381         else:
 382             providers = _ReProvider()
 383         while True:
 384             try:
 385                 providers.probe_write(s_filename, filename + suffix)
 386                 break;
 387             # complex C declarations can fool the pyparsing grammar.
 388             # we could increase the complexity of the grammar
 389             # instead we fall back to string pattern matching
 390             except ParseException:
 391                 err = sys.exc_info()[1]
 392                 print("Warning: Proceeding as if --no-pyparsing was given.\n")
 393                 providers = _ReProvider()
 394     elif build_source:
 395         if HAVE_PYP:
 396             providers = _PypProvider()
 397         else:
 398             providers = _ReProvider()
 399         (ignore, fname) = mkstemp(suffix=".h")
 400         while True:
 401             try:
 402                 providers.probe_write(s_filename, fname)
 403                 break;
 404             except ParseException:
 405                 err = sys.exc_info()[1]
 406                 print("Warning: Proceeding as if --no-pyparsing was given.\n")
 407                 providers = _ReProvider()
 408         if not keep_temps:
 409             os.remove(fname)
 410         else:
 411             print("header: " + fname)
 412
 413         try: # for reproducible-builds purposes, prefer a fixed path name pattern
 414             fname = filename + ".dtrace-temp.c"
 415             fdesc = open(fname, mode='w')
 416         except: # but that doesn't work for  -o /dev/null - see rhbz1504009
 417             (ignore,fname) = mkstemp(suffix=".c")
 418             fdesc = open(fname, mode='w')
 419         providers.semaphore_write(fdesc)
 420         fdesc.close()
 421         cc1 = os.environ.get("CC", "gcc")
 422         cflags = "-g " + os.environ.get("CFLAGS", "").replace('\\\n', ' ').replace('\\\r',' ')
 423         # sanitize any embedded \n etc. goo; PR21063
 424         retcode = call(split(cc1) + defines + includes + split(cflags) +
 425              ["-fPIC", "-I.", "-I@prefix@/include", "-c", fname, "-o",
 426               filename + suffix], shell=False)
 427         if retcode != 0:
 428             print("\"gcc " + fname + "\" failed")
 429             usage()
 430             return 1
 431         if not keep_temps:
 432             os.remove(fname)
 433         else:
 434             print("source: " + fname)
 435
 436     if use_cpp:
 437         if not keep_temps:
 438             os.remove(s_filename)
 439         else:
 440             print("cpp: " + s_filename)
 441
 442     return 0
 443
 444 if __name__ == "__main__":
 445     sys.exit(main())