Question

Is there a tool which given a cgi program, and the arguments (query string, method, file to upload, etc.) would set the correct environment variables, and execute this program (with or without a debugger.

Something like this perl script, only more solid, with a more clear output and input, support for files, etc.

Answer 1

Well, a new open source project was born from this question. I’m copying my answer from here.

If you just want to see your CGI running, you can use my tiny runCGI project.

All you need is to set a yaml file which looks something like this

_exec: /var/cgi-bin/myfile.cgi
method: GET
query_string:
  q: s

and then run

./runCGI myyamlfile.yaml

You will see the output on the console’s standard output.

You can even debug it with gdb, debug runCGI gdb runCGI, run with the correct parameters (run someyaml.yaml), issue tcatch exec (tcatch catches it only once) and then set breakpoints to your CGI file:

$ g++ a.cc -o a.out
$ cat a.yaml
method: GET
_exec: a.out
$ gdb runCGI
GNU gdb 6.8-debian
Copyright (C) 2008 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.  Type "show copying"
and "show warranty" for details.
This GDB was configured as "x86_64-linux-gnu"...
(gdb) tcatch exec
Catchpoint 1 (exec)
(gdb) run a.yaml
Starting program: /home/elazar/runCGI/runCGI a.yaml
Executing new program: /home/elazar/runCGI/a.out
0x00007fc3a24a6a60 in ?? () from /lib64/ld-linux-x86-64.so.2
(gdb) tbreak main
Breakpoint 2 at 0x400577: file a.cc, line 2.
(gdb) c
Continuing.
main (argc=1, argv=0x7fff14891408) at a.cc:2
2       int a =0;
(gdb)