#!/usr/bin/env python
#
# GETBULK command generator
#
# Copyright 1999-2012 by Ilya Etingof <ilya@glas.net>.
#
import sys, time
from pysnmp_apps.cli import main, msgmod, secmod, target, pdu, mibview, base
from pysnmp.entity import engine
from pysnmp.entity.rfc3413 import cmdgen
from pysnmp.proto import rfc1902
from pysnmp import error

def getUsage():
    return "Usage: %s [OPTIONS] <AGENT> <PARAMETERS>\n\
%s%s%s%s\
GETBULK options:\n\
   -C BULKOPTS:   set various application specific behaviours:\n\
              n<NUM>   set non-repeaters to <NUM>\n\
              r<NUM>   set max-repetitions to <NUM>\n\
              c:       do not check returned OIDs are increasing\n\
              t:       display wall-clock time to complete the request\n\
              p:       print the number of variables found\n\
%s%s" % (
        sys.argv[0],
        main.getUsage(),
        msgmod.getUsage(),
        secmod.getUsage(),
        mibview.getUsage(),
        target.getUsage(),
        pdu.getReadUsage()
        )

# Construct c/l interpreter for this app

class Scanner(
    msgmod.MPScannerMixIn,
    secmod.SMScannerMixIn,
    mibview.MibViewScannerMixIn,
    target.TargetScannerMixIn,
    pdu.ReadPduScannerMixIn,
    main.MainScannerMixIn,
    base.ScannerTemplate
    ):
    def t_appopts(self, s):
        r' -C '
        self.rv.append(base.ConfigToken('appopts'))

class Parser(
    msgmod.MPParserMixIn,
    secmod.SMParserMixIn,
    mibview.MibViewParserMixIn,
    target.TargetParserMixIn,
    pdu.ReadPduParserMixIn,
    main.MainParserMixIn,
    base.ParserTemplate
    ):
    def p_appOptions(self, args):
        '''
        Option ::= ApplicationOption

        ApplicationOption ::= appopts whitespace string
        ApplicationOption ::= appopts string
        '''

class __Generator(base.GeneratorTemplate):
    def n_ApplicationOption(self, cbCtx, node):
        snmpEngine, ctx = cbCtx
        if len(node) > 2:
            opt = node[2].attr
        else:
            opt = node[1].attr
        p = n = r = None
        for c in opt:
            if c == 'n':
                p = n = []
            elif c == 'r':
                p = r = []
            elif c == 'c':
                ctx['ignoreNonIncreasingOids'] = 1
                p = None
            elif c == 't':
                ctx['displayWallClock'] = time.time()
                p = None
            elif c == 'p':
                ctx['reportFoundVars'] = 1
                p = None
            elif p is not None and c >= '0' and c <= '9':
                p.append(c)
            else:
                raise error.PySnmpError('bad -C option - "%s"' % c)
        if n is not None:
            ctx['nonRepeaters'] = int(''.join(n))
        if r is not None:
            ctx['maxRepetitions'] = int(''.join(r))
        
def generator(cbCtx, ast):
    snmpEngine, ctx = cbCtx
    return __Generator().preorder((snmpEngine, ctx), ast)
    
snmpEngine = engine.SnmpEngine()

try:
    # Parse c/l into AST
    ast = Parser().parse(
        Scanner().tokenize(' '.join(sys.argv[1:]))
        )

    ctx = {}

    # Apply configuration to SNMP entity
    main.generator((snmpEngine, ctx), ast)
    msgmod.generator((snmpEngine, ctx), ast)
    secmod.generator((snmpEngine, ctx), ast)    
    mibview.generator((snmpEngine, ctx), ast)
    target.generator((snmpEngine, ctx), ast)
    pdu.readPduGenerator((snmpEngine, ctx), ast)
    generator((snmpEngine, ctx), ast)

except error.PySnmpError:
    sys.stderr.write('Error: %s\n%s' % (sys.exc_info()[1], getUsage()))
    sys.exit(-1)

ctx['myHeadVars'] = [ rfc1902.ObjectName(x[0]) for x in ctx['varBinds'] ]
    
# Run SNMP engine

def cbFun(sendRequestHandle, errorIndication, errorStatus, errorIndex,
          varBindTable, cbCtx):
    if errorIndication:
        if errorIndication != 'oidNotIncreasing' or \
               not ctx.get('ignoreNonIncreasingOids'):
            sys.stderr.write('Error: %s\n' % errorIndication)
            return
    if errorStatus:
        sys.stderr.write(
            '%s at %s\n' %
            ( errorStatus.prettyPrint(),
              errorIndex and varBindTable[0][int(errorIndex)-1] or '?' )
            )        
        return
    for varBindRow in varBindTable:
        colIdx = -1; inTableFlag = 0
        for oid, val in varBindRow:
            colIdx = colIdx + 1
            sys.stdout.write('%s\n' % cbCtx['mibViewProxy'].getPrettyOidVal(
                cbCtx['mibViewController'], oid, val
                ))
            if cbCtx['myHeadVars'][colIdx].isPrefixOf(oid):
                inTableFlag = 1
        if cbCtx.get('reportFoundVars'):
            cbCtx['reportFoundVars'] = cbCtx['reportFoundVars'] + len(varBindRow)
        if not inTableFlag:
            return # stop on end-of-table
    return 1 # continue walking

cmdgen.BulkCommandGenerator().sendReq(
    snmpEngine, ctx['addrName'],
    ctx.get('nonRepeaters', 0), ctx.get('maxRepetitions', 25),
    ctx['varBinds'], cbFun, ctx,
    ctx.get('contextEngineId'), ctx.get('contextName', '')
    )

try:
    snmpEngine.transportDispatcher.runDispatcher()
except error.PySnmpError:
    sys.stderr.write('Error: %s\n' % sys.exc_info()[1])
    sys.exit(-1)

if ctx.get('reportFoundVars'):
    sys.stdout.write('Variables found: %s\n' % (ctx['reportFoundVars'] - 1))
if ctx.get('displayWallClock'):
    sys.stdout.write('Total traversal time = %.4f seconds\n' % (time.time() - ctx['displayWallClock']))
