Reporting issues and debugging

Reporting issues

1. Issues can be posted at https://github.com/vlvassilev/yuma123/issues
2. Issue reports must specify the exact version of the source code.
3. Issue reports should provide detailed description of how the problem can be produced and if possible an automated test case like the test cases part of yuma123/netconf/test/netconfd
4. Where applicable issue reports should contain gdb backtrace and core dump file.

Debugging

Usecase: Debugging NETCONF session problems

Enable full sshd session dump by replacing /usr/sbin/netconf-subsystem with a wrapper. Edit /etc/ssh/sshd_config to make sshd use the wrapper and restart sshd:

[root@hadm1 /root]# cat /usr/sbin/netconf-subsystem2 
#!/bin/sh
timestamp-tee -t /tmp/nc-`date +%s`-in.txt 2>/tmp/nc-`date +%s`-its.txt | /usr/sbin/netconf-subsystem | timestamp-tee -t /tmp/nc-`date +%s`-out.txt 2>/tmp/nc-`date +%s`-ots.txt

Usecase: Debugging the YANG module parser

Example gdb session with tk_dump_chain(pcb->tkc) usecase.

v@lmf:~/yuma123-git/netconf/test/netconfd/ietf-netmod-sub-intf-vlan-model$ rm /tmp/ncxserver.sock ; gdb --args /usr/sbin/netconfd --module=./ietf-interfaces-common@2017-03-13.yang --module=./ietf-interfaces-ethernet-like@2017-03-13.yang --module=./ietf-if-l3-vlan@2017-03-13.yang --module=/usr/share/yuma/modules/ietf/iana-if-type.yang --module=./vlans.yang --module=./composite-match.yang --modpath=./:/usr/share/yuma/modules/ --no-startup --superuser=$USER --log-level=debug4
...
Breakpoint 1, parse_path_expr (pcb=0x74ed10, res=0x74eec4) at ../../../netconf/src/ncx/xpath1.c:7768
7768	    val1 = NULL;
(gdb) next
7769	    val2 = NULL;
(gdb) next 
7772	    nexttyp = tk_next_typ(pcb->tkc);
(gdb) bt
#0  parse_path_expr (pcb=0x74ed10, res=0x74eec4) at ../../../netconf/src/ncx/xpath1.c:7772
#1  0x00007ffff7918bae in parse_union_expr (pcb=0x74ed10, res=0x74eec4) at ../../../netconf/src/ncx/xpath1.c:7881
#2  0x00007ffff7918d71 in parse_unary_expr (pcb=0x74ed10, res=0x74eec4) at ../../../netconf/src/ncx/xpath1.c:7974
#3  0x00007ffff7918eb9 in parse_multiplicative_expr (pcb=0x74ed10, res=0x74eec4) at ../../../netconf/src/ncx/xpath1.c:8047
#4  0x00007ffff7919263 in parse_additive_expr (pcb=0x74ed10, res=0x74eec4) at ../../../netconf/src/ncx/xpath1.c:8209
#5  0x00007ffff791956f in parse_relational_expr (pcb=0x74ed10, res=0x74eec4) at ../../../netconf/src/ncx/xpath1.c:8352
#6  0x00007ffff79197be in parse_equality_expr (pcb=0x74ed10, res=0x74eec4) at ../../../netconf/src/ncx/xpath1.c:8477
#7  0x00007ffff7919a7a in parse_and_expr (pcb=0x74ed10, res=0x74eec4) at ../../../netconf/src/ncx/xpath1.c:8605
#8  0x00007ffff7919c50 in parse_or_expr (pcb=0x74ed10, res=0x74eec4) at ../../../netconf/src/ncx/xpath1.c:8701
#9  0x00007ffff7919e05 in parse_expr (pcb=0x74ed10, res=0x74eec4) at ../../../netconf/src/ncx/xpath1.c:8788
#10 0x00007ffff7917f2f in parse_function_call (pcb=0x74ed10, res=0x74eec4) at ../../../netconf/src/ncx/xpath1.c:7395
#11 0x00007ffff7918703 in parse_primary_expr (pcb=0x74ed10, res=0x74eec4) at ../../../netconf/src/ncx/xpath1.c:7641
#12 0x00007ffff791888c in parse_filter_expr (pcb=0x74ed10, res=0x74eec4) at ../../../netconf/src/ncx/xpath1.c:7702
#13 0x00007ffff7918ad6 in parse_path_expr (pcb=0x74ed10, res=0x74eec4) at ../../../netconf/src/ncx/xpath1.c:7813
#14 0x00007ffff7918bae in parse_union_expr (pcb=0x74ed10, res=0x74eec4) at ../../../netconf/src/ncx/xpath1.c:7881
#15 0x00007ffff7918d71 in parse_unary_expr (pcb=0x74ed10, res=0x74eec4) at ../../../netconf/src/ncx/xpath1.c:7974
#16 0x00007ffff7918eb9 in parse_multiplicative_expr (pcb=0x74ed10, res=0x74eec4) at ../../../netconf/src/ncx/xpath1.c:8047
#17 0x00007ffff7919263 in parse_additive_expr (pcb=0x74ed10, res=0x74eec4) at ../../../netconf/src/ncx/xpath1.c:8209
#18 0x00007ffff791956f in parse_relational_expr (pcb=0x74ed10, res=0x74eec4) at ../../../netconf/src/ncx/xpath1.c:8352
#19 0x00007ffff79197be in parse_equality_expr (pcb=0x74ed10, res=0x74eec4) at ../../../netconf/src/ncx/xpath1.c:8477
#20 0x00007ffff7919a7a in parse_and_expr (pcb=0x74ed10, res=0x74eec4) at ../../../netconf/src/ncx/xpath1.c:8605
#21 0x00007ffff7919c50 in parse_or_expr (pcb=0x74ed10, res=0x74eec4) at ../../../netconf/src/ncx/xpath1.c:8701
#22 0x00007ffff7919e05 in parse_expr (pcb=0x74ed10, res=0x74eec4) at ../../../netconf/src/ncx/xpath1.c:8788
#23 0x00007ffff791a57f in xpath1_validate_expr_ex (mod=0x628bc0, obj=0x74ea40, pcb=0x74ed10, missing_is_error=false) at ../../../netconf/src/ncx/xpath1.c:9111
#24 0x00007ffff7936676 in resolve_when (mod=0x628bc0, when=0x74ed10, obj=0x74ea40) at ../../../netconf/src/ncx/yang_obj.c:5340
#25 0x00007ffff793d86e in resolve_xpath (tkc=0x692860, mod=0x628bc0, datadefQ=0x6d1748) at ../../../netconf/src/ncx/yang_obj.c:9433
#26 0x00007ffff793d954 in resolve_xpath (tkc=0x692860, mod=0x628bc0, datadefQ=0x628cd0) at ../../../netconf/src/ncx/yang_obj.c:9458
#27 0x00007ffff793fd46 in yang_obj_resolve_xpath (tkc=0x692860, mod=0x628bc0, datadefQ=0x628cd0) at ../../../netconf/src/ncx/yang_obj.c:10752
#28 0x00007ffff794763f in parse_yang_module (tkc=0x692860, mod=0x628bc0, pcb=0x6c7320, ptyp=YANG_PT_TOP, wasadded=0x7fffffffdb5b) at ../../../netconf/src/ncx/yang_parse.c:3439
#29 0x00007ffff7948414 in yang_parse_from_filespec (filespec=0x648510 "./ietf-interfaces-common@2017-03-13.yang", pcb=0x6c7320, ptyp=YANG_PT_TOP, isyang=true) at ../../../netconf/src/ncx/yang_parse.c:3902
#30 0x00007ffff78c0e6f in try_module (buff=0x648510 "./ietf-interfaces-common@2017-03-13.yang", bufflen=40, path=0x0, path2=0x0, modname=0x0, revision=0x0, mode=NCXMOD_MODE_FILEYANG, usebuff=true, 
    done=0x7fffffffdc7f, pcb=0x6c7320, ptyp=YANG_PT_TOP) at ../../../netconf/src/ncx/ncxmod.c:461
#31 0x00007ffff78c282a in try_module_filespec (mode=NCXMOD_MODE_FILEYANG, modname=0x68fb80 "./ietf-interfaces-common@2017-03-13.yang", modlen=40, pcb=0x6c7320, ptyp=YANG_PT_TOP, retmod=0x7fffffffdd40)
    at ../../../netconf/src/ncx/ncxmod.c:1836
#32 0x00007ffff78c29b0 in load_module (modname=0x68fb80 "./ietf-interfaces-common@2017-03-13.yang", revision=0x0, pcb=0x6c7320, ptyp=YANG_PT_TOP, retmod=0x7fffffffdd40) at ../../../netconf/src/ncx/ncxmod.c:1917
#33 0x00007ffff78c32e7 in try_load_module (pcb=0x6c7320, ptyp=YANG_PT_TOP, modname=0x68fb80 "./ietf-interfaces-common@2017-03-13.yang", revision=0x0, retmod=0x7fffffffddf8)
    at ../../../netconf/src/ncx/ncxmod.c:2274
#34 0x00007ffff78c3daf in ncxmod_load_module (modname=0x68fb80 "./ietf-interfaces-common@2017-03-13.yang", revision=0x0, savedevQ=0x7ffff7ddbaa8 <agt_profile+168>, retmod=0x7fffffffddf8)
    at ../../../netconf/src/ncx/ncxmod.c:2784
#35 0x00007ffff7b9dc79 in agt_init2 () at ../../../netconf/src/agt/agt.c:820
#36 0x0000000000401204 in cmn_init (argc=11, argv=0x7fffffffe0b8, showver=0x7fffffffdfca, showhelpmode=0x7fffffffdfc4, validate_config_only_mode=0x7fffffffdfc3) at ../../../netconf/src/netconfd/netconfd.c:227
#37 0x000000000040138c in main (argc=11, argv=0x7fffffffe0b8) at ../../../netconf/src/netconfd/netconfd.c:345
(gdb) print *pcb
$3 = {qhdr = {hdr_typ = 0, prev = 0x0, next = 0x0}, tkc = 0x74efe0, 
  exprstr = 0x74eef0 "derived-from-or-self(../if:type,\n\t\t     'ianaift:ethernetCsmacd') or\nderived-from-or-self(../if:type, 'ianaift:sonet') or\nderived-from-or-self(../if:type, 'ianaift:atm') or\nderived-from-or-self(../if:"..., reader = 0x0, source = XP_SRC_YANG, errinfo = {qhdr = {hdr_typ = 0, prev = 0x0, next = 0x0}, descr = 0x0, ref = 0x0, error_app_tag = 0x0, error_message = 0x0, seen = false}, 
  logerrors = true, missing_errors = false, targobj = 0x0, altobj = 0x0, varobj = 0x0, curmode = XP_CM_NONE, obj = 0x74ea40, objmod = 0x628bc0, docroot = 0x63c0f0, val = 0x0, val_docroot = 0x0, 
  doctype = XP_DOC_DATABASE, flags = 0, result = 0x0, context = {qhdr = {hdr_typ = 0, prev = 0x0, next = 0x0}, dblslash = false, position = 0, last = 0, node = {objptr = 0x74ea40, valptr = 0x74ea40}}, 
  orig_context = {qhdr = {hdr_typ = 0, prev = 0x0, next = 0x0}, dblslash = false, position = 0, last = 0, node = {objptr = 0x74ea40, valptr = 0x74ea40}}, getvar_fn = 0x0, cookie = 0x0, varbindQ = {
    hdr_typ = 2727, prev = 0x74ee68, next = 0x74ee68}, functions = 0x7ffff7b7dfc0 <functions>, result_cacheQ = {hdr_typ = 2727, prev = 0x64ac90, next = 0x750410}, resnode_cacheQ = {hdr_typ = 2727, 
    prev = 0x7462a0, next = 0x7462a0}, result_count = 3, resnode_count = 1, parseres = NO_ERR, validateres = NO_ERR, valueres = NO_ERR, tkerr = {mod = 0x628bc0, linenum = 338, linepos = 7}, seen = false}
(gdb) call tk_dump_chain(pcb->tkc)

 line(338.12), tk(1), typ(token string)  val(derived-from-or-self)
 line(338.32), tk(2), typ(left paren)  val(()
 line(338.33), tk(3), typ(range separator)  val(..)
 line(338.35), tk(4), typ(forward slash)  val(/)
 line(338.36), tk(5), typ(prefix qualified ID string)  val(type)
*cur* line(338.43), tk(6), typ(comma)  val(,)
 line(338.65), tk(7), typ(single quoted string)  val(ianaift:ethernetCsmacd)
 line(338.89), tk(8), typ(right paren)  val())
 line(338.91), tk(9), typ(token string)  val(or)
 line(338.93), tk(10), typ(token string)  val(derived-from-or-self)
 line(338.113), tk(11), typ(left paren)  val(()
 line(338.114), tk(12), typ(range separator)  val(..)
 line(338.116), tk(13), typ(forward slash)  val(/)
 line(338.117), tk(14), typ(prefix qualified ID string)  val(type)
 line(338.124), tk(15), typ(comma)  val(,)
 line(338.126), tk(16), typ(single quoted string)  val(ianaift:sonet)
 line(338.141), tk(17), typ(right paren)  val())
 line(338.143), tk(18), typ(token string)  val(or)
 line(338.145), tk(19), typ(token string)  val(derived-from-or-self)
 line(338.165), tk(20), typ(left paren)  val(()
 line(338.166), tk(21), typ(range separator)  val(..)
 line(338.168), tk(22), typ(forward slash)  val(/)
 line(338.169), tk(23), typ(prefix qualified ID string)  val(type)
 line(338.176), tk(24), typ(comma)  val(,)
 line(338.178), tk(25), typ(single quoted string)  val(ianaift:atm)
 line(338.191), tk(26), typ(right paren)  val())
 line(338.193), tk(27), typ(token string)  val(or)
 line(338.195), tk(28), typ(token string)  val(derived-from-or-self)
 line(338.215), tk(29), typ(left paren)  val(()
 line(338.216), tk(30), typ(range separator)  val(..)
 line(338.218), tk(31), typ(forward slash)  val(/)
 line(338.219), tk(32), typ(prefix qualified ID string)  val(type)
 line(338.226), tk(33), typ(comma)  val(,)
 line(338.228), tk(34), typ(single quoted string)  val(ianaift:otnOtu)
 line(338.244), tk(35), typ(right paren)  val())
(gdb)