timer-sense-light crashes after web server started

[codelast]

subproject: timer-sense-light

When Mongoose web server embedded in the timer-sense-light started in a thread, it crashed immediately.
It seems that it's because of specifying the web-root for mongoose web server caused the problem, but don't konw why.

GDB debug info

[root@alarmpi deploy]# gdb timer_sense_light core.4929
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Reading symbols from timer_sense_light...done.

warning: core file may not match specified executable file.
[New LWP 4930]
[New LWP 4929]
[New LWP 4931]
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/usr/lib/libthread_db.so.1".
Core was generated by `/root/raspberry-pi/gpio/timer-sense-light/deploy/timer_sense_light /root/raspbe'.
Program terminated with signal SIGSEGV, Segmentation fault.
#0 0x0001f634 in mg_mgr_poll (mgr=0xb6b5ce00, milli=1000) at src/3rd/mongoose.c:2857

2857 tmp = nc->next;
Current thread is 1 (Thread 0xb6b5d450 (LWP 4930)) bt
#0 0x0001f634 in mg_mgr_poll (mgr=0xb6b5ce00, milli=1000) at src/3rd/mongoose.c:2857
#1 0x00012f40 in threadWebHandler () at ./include/thread_web_handler.h:86
#2 0xb6f0d00c in start_thread () from /usr/lib/libpthread.so.0
#3 0xb6c2d718 in ?? () from /usr/lib/libc.so.6

Backtrace stopped: previous frame identical to this frame (corrupt stack?)
(gdb) quit

GDB debug guide

• turn on the core dump for Arch Linux ARM

  ulimit -c unlimited
  sysctl -w kernel.core_pattern=core

• modify Makefile to include debugging info in the binary executable program

  DEBUG = YES

• compile & run the program

  make && make install
  cd deploy/bin && ./run-timer-sense-light.sh

You'll find that a core.xxx(e.g. core.4929) file generated under the same dir as the timer-sense-light executable program.

• run GDB

  gdb timer_sense_light core.xxx
  set args /root/raspberry-pi/gpio/timer-sense-light/deploy/conf/main.conf /root/raspberry-pi/gpio/timer-sense-light/deploy/conf/time-range.txt
  b mongoose.c:2855
  r
  n

[codelast]

Seems that this problem is caused by compiling the Mongoose source by g++ but not gcc, I ran a simple test that using g++ to compile one of the example shipped with Mongoose, then it crashed immediately after running the binary.

[codelast]

Also found that even if compiling the Mongoose source by gcc, and other .cpp files by g++ for this project, the program still crashes, seems that some of the third-party libs are conflicted with Mongoose?

[codelast]

Problem solved.
The crash was caused by this line:

if (mg_stat(httpServerOpts.document_root, &st) != 0) {

Implement the logic by myself instead of using the Mongoose implementation solved the problem.