| Current File : //usr/bin/dtrace |
#!/usr/libexec/platform-python
# vim: et sta sts=4 sw=4 ts=8
# This handles the systemtap equivalent of
# $(DTRACE) $(DTRACEFLAGS) -G -s $^ -o $@
# $(DTRACE) $(DTRACEFLAGS) -h -s $^ -o $@
# which is a step that builds DTrace provider and probe definitions
# Copyright (C) 2009-2018 Red Hat Inc.
#
# This file is part of systemtap, and is free software. You can
# redistribute it and/or modify it under the terms of the GNU General
# Public License (GPL); either version 2, or (at your option) any
# later version.
# ignore line too long, missing docstring, method could be a function,
# too many public methods
# pylint: disable=C0301
# pylint: disable=C0111
# pylint: disable=R0201
# pylint: disable=R0904
import hashlib
import os
import sys
import time
import atexit
from shlex import split
from subprocess import call
try:
from pyparsing import alphas, cStyleComment, delimitedList, Group, \
Keyword, lineno, Literal, nestedExpr, nums, oneOf, OneOrMore, \
Optional, ParseException, ParserElement, restOfLine, restOfLine, \
Suppress, SkipTo, Word, ZeroOrMore
HAVE_PYP = True
except ImportError:
HAVE_PYP = False
# Common file creation methods for pyparsing and string pattern matching
class _HeaderCreator(object):
def init_semaphores(self, fdesc):
# dummy declaration just to make the object file non-empty
fdesc.write("/* Generated by the Systemtap dtrace wrapper */\n\n")
fdesc.write("static void __dtrace (void) __attribute__((unused));\n")
fdesc.write("static void __dtrace (void) {}\n")
fdesc.write("\n#include <sys/sdt.h>\n\n")
def init_probes(self, fdesc):
fdesc.write("/* Generated by the Systemtap dtrace wrapper */\n\n")
fdesc.write("\n#define _SDT_HAS_SEMAPHORES 1\n\n")
fdesc.write("\n#define STAP_HAS_SEMAPHORES 1 /* deprecated */\n\n")
fdesc.write("\n#include <sys/sdt.h>\n\n")
def add_semaphore(self, this_provider, this_probe):
# NB: unsigned short is fixed in ABI
semaphores_def = '\n#if defined STAP_SDT_V1\n'
semaphores_def += '#define %s_%s_semaphore %s_semaphore\n' % \
(this_provider, this_probe, this_probe)
semaphores_def += '#endif\n'
semaphores_def += '#if defined STAP_SDT_V1 || defined STAP_SDT_V2 \n'
semaphores_def += "__extension__ unsigned short %s_%s_semaphore __attribute__ ((unused)) __attribute__ ((section (\".probes\")));\n" % \
(this_provider, this_probe)
semaphores_def += '#else\n'
semaphores_def += "__extension__ unsigned short %s_%s_semaphore __attribute__ ((unused)) __attribute__ ((section (\".probes\"))) __attribute__ ((visibility (\"hidden\")));\n" % \
(this_provider, this_probe)
semaphores_def += '#endif\n'
return semaphores_def
def add_probe(self, this_provider, this_probe, args):
stap_str = ""
this_probe_canon = this_provider.upper() + "_" + this_probe.replace("__", "_").upper()
define_str = "#define %s(" % (this_probe_canon)
comment_str = "/* %s (" % (this_probe_canon)
if len(args) == 0:
stap_str += "DTRACE_PROBE ("
else:
stap_str += "DTRACE_PROBE%d (" % len(args)
stap_str += "%s, %s" % (this_provider, this_probe)
i = 0
while i < len(args):
if i != 0:
define_str += ", "
comment_str += ","
define_str = define_str + "arg%s" % (i + 1)
stap_str = stap_str + ", arg%s" % (i + 1)
for argi in args[i]:
if len(argi) > 0:
comment_str += " %s" % argi
i += 1
stap_str += ")"
comment_str += " ) */"
define_str += ") \\\n"
probe_def = '%s\n' % (comment_str)
probe_def += ('#if defined STAP_SDT_V1\n')
probe_def += ('#define %s_ENABLED() __builtin_expect (%s_semaphore, 0)\n' % \
(this_probe_canon, this_probe))
probe_def += ('#define %s_%s_semaphore %s_semaphore\n' % \
(this_provider, this_probe, this_probe))
probe_def += ('#else\n')
probe_def += ('#define %s_ENABLED() __builtin_expect (%s_%s_semaphore, 0)\n' % \
(this_probe_canon, this_provider, this_probe))
probe_def += ('#endif\n')
# NB: unsigned short is fixed in ABI
probe_def += ("__extension__ extern unsigned short %s_%s_semaphore __attribute__ ((unused)) __attribute__ ((section (\".probes\")));\n" % \
(this_provider, this_probe))
probe_def += (define_str + stap_str + "\n\n")
return probe_def
# Parse using pyparsing if it is available
class _PypProvider(_HeaderCreator):
def __init__(self):
self.ast = []
self.bnf = None
self.dtrace_statements = None
def dtrace_bnf(self):
self.current_probe = ""
if self.dtrace_statements is not None:
return
ParserElement.setDefaultWhitespaceChars(' \f\r\n\t\v')
ident = Word(alphas+"_", alphas+nums+"_$")
probe_ident = Word(alphas+nums+"_$")
semi = Literal(";").suppress()
integer = Word( nums )
lbrace = Literal("{").suppress()
rbrace = Literal("}").suppress()
type_name = ident
varname = ident
PROBE = Keyword("probe")
PROVIDER = Keyword("provider")
array_size = integer | ident
varname_spec = varname + Optional("[" + array_size + "]")
struct_decl = Group(oneOf("struct union") + varname + Suppress(nestedExpr('{','}')) + semi)
enum_decl = Group("enum" + varname + Suppress(nestedExpr('{','}')) + semi)
member_decl = Group((Optional(oneOf("struct unsigned const")) + type_name + Optional(Keyword("const")))
+ Optional(Word("*"), default="") + Optional(varname_spec))
struct_typedef = Group(Literal("typedef") + Literal("struct") + varname
+ Suppress(nestedExpr('{','}'))) + Optional(varname) + semi
typedef = ZeroOrMore("typedef" + (member_decl)) + semi
decls = OneOrMore(struct_typedef | struct_decl | typedef | enum_decl)
def memoize_probe(instring, loc, tokens):
self.current_probe = tokens[0][1]
self.current_lineno = lineno(loc,instring)
probe_decl = Group(PROBE + probe_ident + "(" + Optional(Group(delimitedList(member_decl))) + ")" + Optional(Group(Literal(":") + "(" + Optional(Group(delimitedList(member_decl))) + ")")) + Optional(semi))
probe_decl.setParseAction(memoize_probe)
probe_decls = OneOrMore(probe_decl)
provider_decl = (PROVIDER + Optional(ident)
+ lbrace + Group(probe_decls) + rbrace + Optional(semi))
dtrace_statement = Group (SkipTo("provider", include=False) + provider_decl)
self.dtrace_statements = ZeroOrMore(dtrace_statement)
cplusplus_linecomment = Literal("//") + restOfLine
cpp_linecomment = Literal("#") + restOfLine
self.dtrace_statements.ignore(cStyleComment)
self.dtrace_statements.ignore(cplusplus_linecomment)
self.dtrace_statements.ignore(cpp_linecomment)
self.bnf = self.dtrace_statements
def semaphore_write(self, fdesc):
semaphores_def = ""
self.init_semaphores(fdesc)
for asti in self.ast:
if len(asti) == 0:
continue
# ignore SkipTo token
if asti[0] != "provider":
del asti[0]
if asti[0] == "provider":
# list of probes
for prb in asti[2]:
semaphores_def += self.add_semaphore(asti[1], prb[1])
fdesc.write(semaphores_def)
def probe_write(self, provider, header):
hdr = open(header, mode='w')
self.init_probes(hdr)
self.dtrace_bnf()
try:
try:
self.ast = self.bnf.parseFile(provider, parseAll=True).asList()
except TypeError:
# pyparsing-1.5.0 does not support parseAll
self.ast = self.bnf.parseFile(provider).asList()
except ParseException:
err = sys.exc_info()[1]
if len(self.current_probe):
print("Warning: %s:%s:%d: syntax error near:\nprobe %s\n" % (sys.argv[0], provider, self.current_lineno, self.current_probe))
else:
print("Warning: %s:%s:%d syntax error near:\n%s\n" % (sys.argv[0], provider, err.lineno, err.line))
raise err
probes_def = ""
for asti in self.ast:
if len(asti) == 0:
continue
# ignore SkipTo token
if asti[0] != "provider":
del asti[0]
if asti[0] == "provider":
# list of probes
for prb in asti[2]:
if prb[3] == ')': # No parsed argument list
alist = []
else:
alist = prb[3]
probes_def += self.add_probe(asti[1], prb[1], alist)
hdr.write(probes_def)
hdr.close()
# Parse using regular expressions if pyparsing is not available
class _ReProvider(_HeaderCreator):
def __init__(self):
self.semaphores_def = "\n"
self.provider = []
def __semaphore_append(self, this_probe):
self.semaphores_def += self.add_semaphore(self.provider, this_probe)
def semaphore_write(self, fdesc):
self.init_semaphores(fdesc)
fdesc.write(self.semaphores_def)
def probe_write(self, provider, header):
have_provider = False
fdesc = open(provider)
hdr = open(header, mode='w')
self.init_probes(hdr)
in_comment = False
probes_def = ""
while True:
line = fdesc.readline()
if line == "":
break
if line.find("/*") != -1:
in_comment = True
if line.find("*/") != -1:
in_comment = False
continue
if in_comment:
continue
if line.find("provider") != -1:
tokens = line.split()
have_provider = True
self.provider = tokens[1]
elif have_provider and line.find("probe ") != -1:
while line.find(")") < 0:
line += fdesc.readline()
this_probe = line[line.find("probe ")+5:line.find("(")].strip()
argstr = (line[line.find("(")+1:line.find(")")])
arg = ""
i = 0
args = []
self.__semaphore_append(this_probe)
while i < len(argstr):
if argstr[i:i+1] == ",":
args.append(arg.split())
arg = ""
else:
arg = arg + argstr[i]
i += 1
if len(arg) > 0:
args.append(arg.split())
probes_def += self.add_probe(self.provider, this_probe, args)
elif line.find("}") != -1 and have_provider:
have_provider = False
hdr.write(probes_def)
hdr.close()
def mktemp_determ(sources, suffix):
# for reproducible-builds purposes, use a predictable tmpfile path
sha = hashlib.sha256()
for source in sources:
sha.update(source.encode('utf-8'))
fname = ".dtrace-temp." + sha.hexdigest()[:8] + suffix
tries = 0
while True:
tries += 1
if tries > 100: # if file exists due to previous crash or whatever
raise Exception("cannot create temporary file \""+fname+"\"")
try:
wxmode = 'x' if sys.version_info > (3,0) else 'wx'
fdesc = open(fname, mode=wxmode)
break
except FileExistsError:
time.sleep(0.1) # vague estimate of elapsed time for concurrent identical gcc job
pass # Try again
return fdesc, fname
def usage():
print("Usage " + sys.argv[0] + " [--help] [-h | -G] [-C [-I<Path>]] -s File.d [-o <File>]")
def dtrace_help():
usage()
print("Where -h builds a systemtap header file from the .d file")
print(" -C when used with -h, also run cpp preprocessor")
print(" -o specifies an explicit output file name,")
print(" the default for -G is file.o and -h is file.h")
print(" -I when running cpp pass through this -I include Path")
print(" -s specifies the name of the .d input file")
print(" -G builds a stub file.o from file.d,")
print(" which is required by some packages that use dtrace.")
sys.exit(1)
########################################################################
# main
########################################################################
def main():
if len(sys.argv) < 2:
usage()
return 1
global HAVE_PYP
i = 1
build_header = False
build_source = False
keep_temps = False
use_cpp = False
suffix = ""
filename = ""
s_filename = ""
includes = []
defines = []
ignore_options = ["-64", "-32", "-fpic", "-fPIC"]
ignore_options2 = ["-x"] # with parameter
while i < len(sys.argv):
if sys.argv[i] == "-o":
i += 1
filename = sys.argv[i]
elif sys.argv[i] == "-s":
i += 1
s_filename = sys.argv[i]
elif sys.argv[i] == "-C":
use_cpp = True
elif sys.argv[i].startswith("-D"):
defines.append(sys.argv[i])
elif sys.argv[i] == "-h":
build_header = True
suffix = ".h"
elif sys.argv[i].startswith("-I"):
includes.append(sys.argv[i])
elif sys.argv[i] == "-G":
build_source = True
suffix = ".o"
elif sys.argv[i] == "-k":
keep_temps = True
elif sys.argv[i] == "--no-pyparsing":
HAVE_PYP = False
elif sys.argv[i] == "--types":
print(sys.argv[0] + ": note: obsolete option --types used")
elif sys.argv[i] in ignore_options:
pass # dtrace users sometimes pass these flags
elif sys.argv[i] in ignore_options2:
i += 1
pass # dtrace users sometimes pass these flags
elif sys.argv[i] == "--help":
dtrace_help()
elif sys.argv[i][0] == "-":
print(sys.argv[0], "invalid option", sys.argv[i])
usage()
return 1
i += 1
if not build_header and not build_source:
usage()
return 1
if s_filename != "" and use_cpp:
(ignore, fname) = mktemp_determ(["use_cpp", s_filename], suffix=".d")
cpp = os.environ.get("CPP", "cpp")
retcode = call(split(cpp) + includes + defines + [s_filename, '-o', fname])
if retcode != 0:
print("\"cpp includes s_filename\" failed")
usage()
return 1
s_filename = fname
if filename == "":
if s_filename != "":
(filename, ignore) = os.path.splitext(s_filename)
filename = os.path.basename(filename)
else:
usage()
return 1
else:
suffix = ""
if build_header:
if HAVE_PYP:
providers = _PypProvider()
else:
providers = _ReProvider()
while True:
try:
providers.probe_write(s_filename, filename + suffix)
break;
# complex C declarations can fool the pyparsing grammar.
# we could increase the complexity of the grammar
# instead we fall back to string pattern matching
except ParseException:
err = sys.exc_info()[1]
print("Warning: Proceeding as if --no-pyparsing was given.\n")
providers = _ReProvider()
elif build_source:
if HAVE_PYP:
providers = _PypProvider()
else:
providers = _ReProvider()
(fdesc, fname) = mktemp_determ(["build_source", s_filename], suffix=".h")
while True:
try:
providers.probe_write(s_filename, fname)
break;
except ParseException:
err = sys.exc_info()[1]
print("Warning: Proceeding as if --no-pyparsing was given.\n")
providers = _ReProvider()
if not keep_temps:
os.remove(fname)
else:
print("header: " + fname)
(fdesc, fname) = mktemp_determ(["build_source", s_filename, filename], suffix=".c")
if not keep_temps:
atexit.register(os.remove, fname) # delete generated source at exit, even if error
providers.semaphore_write(fdesc)
fdesc.close()
cc1 = os.environ.get("CC", "gcc")
cflags = "-g " + os.environ.get("CFLAGS", "").replace('\\\n', ' ').replace('\\\r',' ')
# sanitize any embedded \n etc. goo; PR21063
retcode = call(split(cc1) + defines + includes + split(cflags) +
["-fPIC", "-I.", "-I/usr/include", "-c", fname, "-o",
filename + suffix], shell=False)
if retcode != 0:
print("\"gcc " + fname + "\" failed")
usage()
return 1
if keep_temps:
print("source: " + fname)
if use_cpp:
if not keep_temps:
os.remove(s_filename)
else:
print("cpp: " + s_filename)
return 0
if __name__ == "__main__":
sys.exit(main())
# Local Variables:
# mode: python
# End: