Commit graph

5 commits

Author SHA1 Message Date
Justine Tunney
226aaf3547 Improve memory safety
This commit makes numerous refinements to cosmopolitan memory handling.

The default stack size has been reduced from 2mb to 128kb. A new macro
is now provided so you can easily reconfigure the stack size to be any
value you want. Work around the breaking change by adding to your main:

    STATIC_STACK_SIZE(0x00200000);  // 2mb stack

If you're not sure how much stack you need, then you can use:

    STATIC_YOINK("stack_usage_logging");

After which you can `sort -nr o/$MODE/stack.log`. Based on the unit test
suite, nothing in the Cosmopolitan repository (except for Python) needs
a stack size greater than 30kb. There are also new macros for detecting
the size and address of the stack at runtime, e.g. GetStackAddr(). We
also now support sigaltstack() so if you want to see nice looking crash
reports whenever a stack overflow happens, you can put this in main():

    ShowCrashReports();

Under `make MODE=dbg` and `make MODE=asan` the unit testing framework
will now automatically print backtraces of memory allocations when
things like memory leaks happen. Bugs are now fixed in ASAN global
variable overrun detection. The memtrack and asan runtimes also handle
edge cases now. The new tools helped to identify a few memory leaks,
which are fixed by this change.

This change should fix an issue reported in #288 with ARG_MAX limits.
Fixing this doubled the performance of MKDEPS.COM and AR.COM yet again.
2021-10-13 17:27:13 -07:00
Justine Tunney
4e56d89dcd Eliminate some flakes
- Get ASAN working on Windows.

- Deleting directories and then recreating them with the same name in a
  short period of time appears to be a no-no on Windows.

- There's no reason to call FlushFileBuffers on close() for pipes, and
  it's harmful since it might block indefinitely for no good reason.
2021-02-03 06:25:27 -08:00
Justine Tunney
37a4c70c36 Change license 2020-12-27 17:18:44 -08:00
Justine Tunney
3e4fd4b0ad Add epoll and do more release readiness changes
This change also pays off some of the remaining technical debt with
stdio, file descriptors, and memory managemnt polyfills.
2020-11-28 12:01:51 -08:00
Justine Tunney
c91b3c5006 Initial import 2020-06-15 07:18:57 -07:00