Pull request #68 prevents Backtrace from being built on Swift 5.9 and above,
but Demangle is still built and fails when the importing project uses musl.
motivation: print crash trace on segmentation faults and other common failures beyond illegal instructions
changes:
* include SIGSEGV, SIGBUS and SIGFPE in the default signals trapped
* update and improve tests
Add an implementation across all architectures supported by Windows:
- x86
- x86_64
- ARM
- ARM64
This relies on DbgHlp32.dll which makes this unfriendly to store
applications. We can investigate improvements to that in the future.
This sketches out an implementation which allows building and using the
interface for providing backtraces. This requires that the programs be
built with debug information in CodeView format. Without the additional
debug information, the stack traces will be limited to symbolication and
resolution to export only symbols.
Resolves: #34
Motivation:
Previously, we would use
`CommandLine.arguments[0]`/`argv[0]`/`getexecname()` as the preferred
ways to find the main binary. That sounds sensible, especially given
the fact that we'd fall back onto other methods (such as
`/proc/self/exe`) when the previous ones don't work.
There is however an unfortunate edge case. If you for example have your
app binary at `/app/app` and you start it with a relative path `./app`
from within `/app`, then `CommandLine.arguments[0]` will only contain
`./app`. If now the app changes its working directory to `/`, `./app`
would mean `/app` which is the directory. This would mean we will find
the target but instead of the binary we'd find the directory `/app`.
From then on, everything else fails.
A similar problem is if `argv[0]` was actually set incorrectly when
`exec*`ing the process. This has happened at least in one instance.
Modification:
Given that we only target Linux here, we can actually here, we can
change the order in which we try to find the main binary. We can start
by using `/proc/self/exe` which is a very high quality and almost
guaranteed to work way to find the main binary, nevermind the
information in `argv`.
Result:
More robust symbolications, especially in environments like Heroku/Dokku
where we've seen `argv` not being set correctly.
Motivation:
In case SwiftBacktrace fails, we get only very little output.
Unfortunately, some crucial information (like the errno) is missing and
in case `mmap` fails, we don't know if the problem is file I/O or
allocating memory.
Modification:
- print errnos
- distinguish the two mmaps
Result:
Easier debugging
motivation: reduce public API surface area given the plan is to abosrb this library in the language runtime eventually
changes:
* make print function private
* remove explicit swift-server file
motivation: setup ci for the project
changes:
* add docker setup for testing 5.0, 5.1 and 5.2
* fix license headers
* add sanity script
* format
* regenerate tests to match convention
Euan Harris
Alastair Houghton
Yim Lee
tom doron
Fabio1988
Johannes Weiss
tomer doron
Saleem Abdulrasool
Johannes Weiss
Ian Partridge
Zsolt Váradi