`libssh2_channel_get_exit_status()` returns 0 both for a real exit
status of 0 and for a channel that never received an `exit-status`
request. A server that force-closes a session, like OpenSSH under
`ChannelTimeout`, makes a still-running command look like a clean exit
0. Reproduction with the stock `example/ssh2_exec` is in #2515.
This adds `libssh2_channel_has_exit_status()`, returning 1 once the
request arrived, the name you suggested.
The new field sits in `_LIBSSH2_CHANNEL` in `libssh2_priv.h` and callers
only ever hold a pointer, so no ABI change.
`libssh2_channel_get_exit_signal()` already lets a caller see whether
that request arrived by leaving the pointer NULL, exit-status was the
odd one out.
Man page and a `test_exit_status` covering both states are included.
Follow-up to 77bd3c1215Fixes#2515Closes#2516
Returning for example (without newlines):
```
crypto:LibreSSL MD5:off MD5-PEM:off RIPEMD160:off DSA:off
RSA:on RSA-SHA1:on ECDSA:on ED25519:on ML-KEM:off
AES-CTR:on AES-CBC:on BLOWFISH:off RC4:off CAST:off
3DES:off zlib:on clear-memory:on debug-logging:on
```
To allow library users to find out these details, and add a searchable
static string to binaries with this information.
Possible values for `crypto`: `AWS-LC`, `BoringSSL`, `Libgcrypt`,
`LibreSSL`, `mbedTLS`, `OpenSSL`, `OpenSSL/1.1.1`, `OS400QC3`, `WinCNG`,
`wolfSSL`.
Also:
- replace manual translation of crypto engine enum to name in CMake
integration test snippet with the new API.
Fixes#2161Closes#2178
To render in Git webviews as-is, to make it easier to edit, verify,
and to sync up with curl.
- add options to not build the `.3` man pages:
- autotools: `--disable-docs`
- cmake: `LIBSSH2_BUILD_DOCS=OFF`
- building `.3` man pages requires Perl after this patch.
- drop `mansyntax` and the shell / `grep` / GNU `man` tool requirements with it.
- scripts and most logic were copied from curl.
- add `cd2nroff` from curl, with edits to relax curl-specific checks.
- used `nroff2cd` (from curl) to convert from `.3` to `.md`. Then
manually fixed copyrights, inline function references and a couple
of other things.
Credits-to: Daniel Stenberg
Ref: eefcc1bda4
Ref: https://github.com/curl/curl/pull/12730
Ref: https://github.com/libssh2/www/issues/25#issuecomment-3289431671Closes#1660
