Ever wished you could ignore errors and just keep going like Visual Basic's
great On Error Resume Next, but in C? Well, now you can!
An "error" in this case means segmentation fault. More signals may be caught and ignored in the future. A mode that catches and hides all error codes from system calls may also be considered.
See the source of the demo executable in segvign.c for more inspiration and
usage, and the doc comments in on_error.h for actual documentation.
Including the header defines a handful of functions/macros for setting up error handling:
-
on_error_resume_next(): the star of the show, just lets you get on with stuff and not do errors at all. -
on_error_goto(fail): goto fail, but do it automatically on errors. The label should be defined in the same function. -
on_error_goto_unsafe(fail): like above, but even less safe.
Link against lib_on_error.so for the runtime functions used by the macros.
libnocrash.so is a self-contained LD_PRELOAD-able shared library that calls
on_error_resume_next() when loaded, protecting any process against unwanted
segmentation faults without requiring any source changes to the application.
This can be loaded manually by setting LD_PRELOAD or by using the nocrash
script like so:
./nocrash ./crash
(Where crash is a simple test program included in this repo that simply crashes directly.)
The code itself is MIT license, but uses bitdefender's bddisasm which is APLv2 licensed.
- Clone bddisasm repo into a subdirectory
- Run
make
This will produce a lib_on_error.so shared library that can be linked into
your own programs, as well as a demo executable in statically linked
(segvign) and dynamically linked (segvign_dyn) forms.
There's no way to disable the error handling, you just have to make sure to update the error handling label as you go.
Or call on_error_resume_next() once at startup and leave it. You never want
your program to crash anyway.