Mini Shell
#
# This file is part of pysmi software.
#
# Copyright (c) 2015-2019, Ilya Etingof <etingof@gmail.com>
# License: http://snmplabs.com/pysmi/license.html
#
import sys
import os
import time
try:
from pwd import getpwuid
except ImportError:
# noinspection PyPep8
getpwuid = lambda x: ['<unknown>']
from pysmi import __name__ as packageName
from pysmi import __version__ as packageVersion
from pysmi.mibinfo import MibInfo
from pysmi.codegen.symtable import SymtableCodeGen
from pysmi import error
from pysmi import debug
class MibStatus(str):
"""Indicate MIB transformation result.
*MibStatus* is a subclass of Python string type. Some additional
attributes may be set to indicate the details.
The following *MibStatus* class instances are defined:
* *compiled* - MIB is successfully transformed
* *untouched* - fresh transformed version of this MIB already exisits
* *failed* - MIB transformation failed. *error* attribute carries details.
* *unprocessed* - MIB transformation required but waived for some reason
* *missing* - ASN.1 MIB source can't be found
* *borrowed* - MIB transformation failed but pre-transformed version was used
"""
def setOptions(self, **kwargs):
n = self.__class__(self)
for k in kwargs:
setattr(n, k, kwargs[k])
return n
statusCompiled = MibStatus('compiled')
statusUntouched = MibStatus('untouched')
statusFailed = MibStatus('failed')
statusUnprocessed = MibStatus('unprocessed')
statusMissing = MibStatus('missing')
statusBorrowed = MibStatus('borrowed')
class MibCompiler(object):
"""Top-level, user-facing, composite MIB compiler object.
MibCompiler implements high-level MIB transformation processing logic.
It executes its actions by calling the following specialized objects:
* *readers* - to acquire ASN.1 MIB data
* *searchers* - to see if transformed MIB already exists and no processing is necessary
* *parser* - to parse ASN.1 MIB into AST
* *code generator* - to perform actual MIB transformation
* *borrowers* - to fetch pre-transformed MIB if transformation is impossible
* *writer* - to store transformed MIB data
Required components must be passed to MibCompiler on instantiation. Those
components are: *parser*, *codegenerator* and *writer*.
Optional components could be set or modified at later phases of MibCompiler
life. Unlike singular, required components, optional one can be present
in sequences to address many possible sources of data. They are
*readers*, *searchers* and *borrowers*.
"""
indexFile = 'index'
def __init__(self, parser, codegen, writer):
"""Creates an instance of *MibCompiler* class.
Args:
parser: ASN.1 MIB parser object
codegen: MIB transformation object
writer: transformed MIB storing object
"""
self._parser = parser
self._codegen = codegen
self._symbolgen = SymtableCodeGen()
self._writer = writer
self._sources = []
self._searchers = []
self._borrowers = []
def addSources(self, *sources):
"""Add more ASN.1 MIB source repositories.
MibCompiler.compile will invoke each of configured source objects
in order of their addition asking each to fetch MIB module specified
by name.
Args:
sources: reader object(s)
Returns:
reference to itself (can be used for call chaining)
"""
self._sources.extend(sources)
debug.logger & debug.flagCompiler and debug.logger(
'current MIB source(s): %s' % ', '.join([str(x) for x in self._sources]))
return self
def addSearchers(self, *searchers):
"""Add more transformed MIBs repositories.
MibCompiler.compile will invoke each of configured searcher objects
in order of their addition asking each if already transformed MIB
module already exists and is more recent than specified.
Args:
searchers: searcher object(s)
Returns:
reference to itself (can be used for call chaining)
"""
self._searchers.extend(searchers)
debug.logger & debug.flagCompiler and debug.logger(
'current compiled MIBs location(s): %s' % ', '.join([str(x) for x in self._searchers]))
return self
def addBorrowers(self, *borrowers):
"""Add more transformed MIBs repositories to borrow MIBs from.
Whenever MibCompiler.compile encounters MIB module which neither of
the *searchers* can find or fetched ASN.1 MIB module can not be
parsed (due to syntax errors), these *borrowers* objects will be
invoked in order of their addition asking each if already transformed
MIB can be fetched (borrowed).
Args:
borrowers: borrower object(s)
Returns:
reference to itself (can be used for call chaining)
"""
self._borrowers.extend(borrowers)
debug.logger & debug.flagCompiler and debug.logger(
'current MIB borrower(s): %s' % ', '.join([str(x) for x in self._borrowers]))
return self
def _get_system_info(self):
try:
platform_info = os.uname()
except AttributeError:
platform_info = ('?',) * 6
try:
user_info = getpwuid(os.getuid())
except Exception:
user_info = ('?',) * 7
return platform_info, user_info
def compile(self, *mibnames, **options):
"""Transform requested and possibly referred MIBs.
The *compile* method should be invoked when *MibCompiler* object
is operational meaning at least *sources* are specified.
Once called with a MIB module name, *compile* will:
* fetch ASN.1 MIB module with given name by calling *sources*
* make sure no such transformed MIB already exists (with *searchers*)
* parse ASN.1 MIB text with *parser*
* perform actual MIB transformation into target format with *code generator*
* may attempt to borrow pre-transformed MIB through *borrowers*
* write transformed MIB through *writer*
The above sequence will be performed for each MIB name given in
*mibnames* and may be performed for all MIBs referred to from
MIBs being processed.
Args:
mibnames: list of ASN.1 MIBs names
options: options that affect the way PySMI components work
Returns:
A dictionary of MIB module names processed (keys) and *MibStatus*
class instances (values)
"""
processed = {}
parsedMibs = {}
failedMibs = {}
borrowedMibs = {}
builtMibs = {}
symbolTableMap = {}
mibsToParse = [x for x in mibnames]
canonicalMibNames = {}
while mibsToParse:
mibname = mibsToParse.pop(0)
if mibname in parsedMibs:
debug.logger & debug.flagCompiler and debug.logger('MIB %s already parsed' % mibname)
continue
if mibname in failedMibs:
debug.logger & debug.flagCompiler and debug.logger('MIB %s already failed' % mibname)
continue
for source in self._sources:
debug.logger & debug.flagCompiler and debug.logger('trying source %s' % source)
try:
fileInfo, fileData = source.getData(mibname)
for mibTree in self._parser.parse(fileData):
mibInfo, symbolTable = self._symbolgen.genCode(
mibTree, symbolTableMap
)
symbolTableMap[mibInfo.name] = symbolTable
parsedMibs[mibInfo.name] = fileInfo, mibInfo, mibTree
if mibname in failedMibs:
del failedMibs[mibname]
mibsToParse.extend(mibInfo.imported)
if fileInfo.name in mibnames:
if mibInfo.name not in canonicalMibNames:
canonicalMibNames[mibInfo.name] = []
canonicalMibNames[mibInfo.name].append(fileInfo.name)
debug.logger & debug.flagCompiler and debug.logger(
'%s (%s) read from %s, immediate dependencies: %s' % (
mibInfo.name, mibname, fileInfo.path, ', '.join(mibInfo.imported) or '<none>'))
break
except error.PySmiReaderFileNotFoundError:
debug.logger & debug.flagCompiler and debug.logger('no %s found at %s' % (mibname, source))
continue
except error.PySmiError:
exc_class, exc, tb = sys.exc_info()
exc.source = source
exc.mibname = mibname
exc.msg += ' at MIB %s' % mibname
debug.logger & debug.flagCompiler and debug.logger('%serror %s from %s' % (
options.get('ignoreErrors') and 'ignoring ' or 'failing on ', exc, source))
failedMibs[mibname] = exc
processed[mibname] = statusFailed.setOptions(error=exc)
else:
exc = error.PySmiError('MIB source %s not found' % mibname)
exc.mibname = mibname
debug.logger & debug.flagCompiler and debug.logger('no %s found everywhere' % mibname)
if mibname not in failedMibs:
failedMibs[mibname] = exc
if mibname not in processed:
processed[mibname] = statusMissing
debug.logger & debug.flagCompiler and debug.logger(
'MIBs analyzed %s, MIBs failed %s' % (len(parsedMibs), len(failedMibs)))
#
# See what MIBs need generating
#
for mibname in tuple(parsedMibs):
fileInfo, mibInfo, mibTree = parsedMibs[mibname]
debug.logger & debug.flagCompiler and debug.logger('checking if %s requires updating' % mibname)
for searcher in self._searchers:
try:
searcher.fileExists(mibname, fileInfo.mtime, rebuild=options.get('rebuild'))
except error.PySmiFileNotFoundError:
debug.logger & debug.flagCompiler and debug.logger(
'no compiled MIB %s available through %s' % (mibname, searcher))
continue
except error.PySmiFileNotModifiedError:
debug.logger & debug.flagCompiler and debug.logger(
'will be using existing compiled MIB %s found by %s' % (mibname, searcher))
del parsedMibs[mibname]
processed[mibname] = statusUntouched
break
except error.PySmiError:
exc_class, exc, tb = sys.exc_info()
exc.searcher = searcher
exc.mibname = mibname
exc.msg += ' at MIB %s' % mibname
debug.logger & debug.flagCompiler and debug.logger('error from %s: %s' % (searcher, exc))
continue
else:
debug.logger & debug.flagCompiler and debug.logger(
'no suitable compiled MIB %s found anywhere' % mibname)
if options.get('noDeps') and mibname not in canonicalMibNames:
debug.logger & debug.flagCompiler and debug.logger(
'excluding imported MIB %s from code generation' % mibname)
del parsedMibs[mibname]
processed[mibname] = statusUntouched
continue
debug.logger & debug.flagCompiler and debug.logger(
'MIBs parsed %s, MIBs failed %s' % (len(parsedMibs), len(failedMibs)))
#
# Generate code for parsed MIBs
#
for mibname in parsedMibs.copy():
fileInfo, mibInfo, mibTree = parsedMibs[mibname]
debug.logger & debug.flagCompiler and debug.logger('compiling %s read from %s' % (mibname, fileInfo.path))
platform_info, user_info = self._get_system_info()
comments = [
'ASN.1 source %s' % fileInfo.path,
'Produced by %s-%s at %s' % (packageName, packageVersion, time.asctime()),
'On host %s platform %s version %s by user %s' % (platform_info[1], platform_info[0],
platform_info[2], user_info[0]),
'Using Python version %s' % sys.version.split('\n')[0]
]
try:
mibInfo, mibData = self._codegen.genCode(
mibTree,
symbolTableMap,
comments=comments,
genTexts=options.get('genTexts'),
textFilter=options.get('textFilter')
)
builtMibs[mibname] = fileInfo, mibInfo, mibData
del parsedMibs[mibname]
debug.logger & debug.flagCompiler and debug.logger(
'%s read from %s and compiled by %s' % (mibname, fileInfo.path, self._writer))
except error.PySmiError:
exc_class, exc, tb = sys.exc_info()
exc.handler = self._codegen
exc.mibname = mibname
exc.msg += ' at MIB %s' % mibname
debug.logger & debug.flagCompiler and debug.logger('error from %s: %s' % (self._codegen, exc))
processed[mibname] = statusFailed.setOptions(error=exc)
failedMibs[mibname] = exc
del parsedMibs[mibname]
debug.logger & debug.flagCompiler and debug.logger(
'MIBs built %s, MIBs failed %s' % (len(parsedMibs), len(failedMibs)))
#
# Try to borrow pre-compiled MIBs for failed ones
#
for mibname in failedMibs.copy():
if options.get('noDeps') and mibname not in canonicalMibNames:
debug.logger & debug.flagCompiler and debug.logger('excluding imported MIB %s from borrowing' % mibname)
continue
for borrower in self._borrowers:
debug.logger & debug.flagCompiler and debug.logger('trying to borrow %s from %s' % (mibname, borrower))
try:
fileInfo, fileData = borrower.getData(
mibname,
genTexts=options.get('genTexts')
)
borrowedMibs[mibname] = fileInfo, MibInfo(name=mibname, imported=[]), fileData
del failedMibs[mibname]
debug.logger & debug.flagCompiler and debug.logger('%s borrowed with %s' % (mibname, borrower))
break
except error.PySmiError:
debug.logger & debug.flagCompiler and debug.logger('error from %s: %s' % (borrower, sys.exc_info()[1]))
debug.logger & debug.flagCompiler and debug.logger(
'MIBs available for borrowing %s, MIBs failed %s' % (len(borrowedMibs), len(failedMibs)))
#
# See what MIBs need borrowing
#
for mibname in borrowedMibs.copy():
debug.logger & debug.flagCompiler and debug.logger('checking if failed MIB %s requires borrowing' % mibname)
fileInfo, mibInfo, mibData = borrowedMibs[mibname]
for searcher in self._searchers:
try:
searcher.fileExists(mibname, fileInfo.mtime, rebuild=options.get('rebuild'))
except error.PySmiFileNotFoundError:
debug.logger & debug.flagCompiler and debug.logger(
'no compiled MIB %s available through %s' % (mibname, searcher))
continue
except error.PySmiFileNotModifiedError:
debug.logger & debug.flagCompiler and debug.logger(
'will be using existing compiled MIB %s found by %s' % (mibname, searcher))
del borrowedMibs[mibname]
processed[mibname] = statusUntouched
break
except error.PySmiError:
exc_class, exc, tb = sys.exc_info()
exc.searcher = searcher
exc.mibname = mibname
exc.msg += ' at MIB %s' % mibname
debug.logger & debug.flagCompiler and debug.logger('error from %s: %s' % (searcher, exc))
continue
else:
debug.logger & debug.flagCompiler and debug.logger(
'no suitable compiled MIB %s found anywhere' % mibname)
if options.get('noDeps') and mibname not in canonicalMibNames:
debug.logger & debug.flagCompiler and debug.logger(
'excluding imported MIB %s from borrowing' % mibname)
processed[mibname] = statusUntouched
else:
debug.logger & debug.flagCompiler and debug.logger('will borrow MIB %s' % mibname)
builtMibs[mibname] = borrowedMibs[mibname]
processed[mibname] = statusBorrowed.setOptions(
path=fileInfo.path, file=fileInfo.file,
alias=fileInfo.name
)
del borrowedMibs[mibname]
debug.logger & debug.flagCompiler and debug.logger(
'MIBs built %s, MIBs failed %s' % (len(builtMibs), len(failedMibs)))
#
# We could attempt to ignore missing/failed MIBs
#
if failedMibs and not options.get('ignoreErrors'):
debug.logger & debug.flagCompiler and debug.logger('failing with problem MIBs %s' % ', '.join(failedMibs))
for mibname in builtMibs:
processed[mibname] = statusUnprocessed
return processed
debug.logger & debug.flagCompiler and debug.logger(
'proceeding with built MIBs %s, failed MIBs %s' % (', '.join(builtMibs), ', '.join(failedMibs)))
#
# Store compiled MIBs
#
for mibname in builtMibs.copy():
fileInfo, mibInfo, mibData = builtMibs[mibname]
try:
if options.get('writeMibs', True):
self._writer.putData(
mibname, mibData, dryRun=options.get('dryRun')
)
debug.logger & debug.flagCompiler and debug.logger('%s stored by %s' % (mibname, self._writer))
del builtMibs[mibname]
if mibname not in processed:
processed[mibname] = statusCompiled.setOptions(
path=fileInfo.path,
file=fileInfo.file,
alias=fileInfo.name,
oid=mibInfo.oid,
oids=mibInfo.oids,
identity=mibInfo.identity,
revision=mibInfo.revision,
enterprise=mibInfo.enterprise,
compliance=mibInfo.compliance,
)
except error.PySmiError:
exc_class, exc, tb = sys.exc_info()
exc.handler = self._codegen
exc.mibname = mibname
exc.msg += ' at MIB %s' % mibname
debug.logger & debug.flagCompiler and debug.logger('error %s from %s' % (exc, self._writer))
processed[mibname] = statusFailed.setOptions(error=exc)
failedMibs[mibname] = exc
del builtMibs[mibname]
debug.logger & debug.flagCompiler and debug.logger(
'MIBs modified: %s' % ', '.join([x for x in processed if processed[x] in ('compiled', 'borrowed')]))
return processed
def buildIndex(self, processedMibs, **options):
platform_info, user_info = self._get_system_info()
comments = [
'Produced by %s-%s at %s' % (packageName, packageVersion, time.asctime()),
'On host %s platform %s version %s by user %s' % (platform_info[1], platform_info[0],
platform_info[2], user_info[0]),
'Using Python version %s' % sys.version.split('\n')[0]
]
try:
self._writer.putData(
self.indexFile,
self._codegen.genIndex(
processedMibs,
comments=comments,
old_index_data=self._writer.getData(self.indexFile)
),
dryRun=options.get('dryRun')
)
except error.PySmiError:
exc_class, exc, tb = sys.exc_info()
exc.msg += ' at MIB index %s' % self.indexFile
debug.logger & debug.flagCompiler and debug.logger('error %s when building %s' % (exc, self.indexFile))
if options.get('ignoreErrors'):
return
if hasattr(exc, 'with_traceback'):
raise exc.with_traceback(tb)
else:
raise exc
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