#6338 introduces regression when building with LibreSSL (3.5.0).
```
cc -Wno-unused-result -Wsign-compare -Wunreachable-code -DNDEBUG -O2 -pipe -g -fPIC -O2 -pipe -g -O2 -pipe -g -O2 -pipe -fPIC -Isrc/borg/crypto -I/usr/local/include/python3.9 -c src/borg/crypto/low_level.c -o /tmp/ports/pobj/borgbackup-1.2.1/borg-eec359cf228caf00d9c72bde07bf939872e9d3fa/temp.openbsd-7.1-amd64-3.9/src/borg/crypto/low_level.o
src/borg/crypto/low_level.c:12439:48: error: use of undeclared identifier 'EVP_chacha20_poly1305'; did you mean 'EVP_aead_chacha20_poly1305'?
__pyx_v_self->__pyx_base.__pyx_base.cipher = EVP_chacha20_poly1305;
^~~~~~~~~~~~~~~~~~~~~
EVP_aead_chacha20_poly1305
/usr/include/openssl/evp.h:1161:17: note: 'EVP_aead_chacha20_poly1305' declared here
const EVP_AEAD *EVP_aead_chacha20_poly1305(void);
^
1 error generated.
```
Unfortunately `EVP_aead_chacha20_poly1305`, offered by LibreSSL, is not
a drop in replacement for `EVP_chacha20_poly1305`. More info on the
first can be found at https://man.openbsd.org/EVP_AEAD_CTX_init.3.
This resolves a compiler warning from the generated code that
resulted from a comparison of two local variables of different
signedness. The issue is resolved by changing the type of both
to int since this seems like the safest choice available.
All these are unsupported since long.
Newer versions of LibreSSL have gained chacha20-poly1305 support,
but still lack aes256-ocb support.
Also they have the HMAC_CTX_new/free api now.
docs: openssl >= 1.1.1 is required now
anything older is out of support anyway.
The generated source code was producing a compiler warning due to
the pointers differing in constness. The called function expects
a non-const pointer while the generated code produces a const pointer
via a cast. This changes the cast to drop 'const' to make the compiler
happy.
docs: clarify on-disk order and size of log entry fields
The order of the fields of a log entry on disk is CRC32 first, the docs had the size first.
I tried to make this list similar to the HashIndex struct description.
Thanks to Andrey Bienkowski (@hexagonrecursion) for reporting this and writing reproducer code.
Changes:
- use different, randomly (but recognizably) named temp files while writing (securely made by os.mkstemp())
- make sure temp files are cleaned up in normal and error conditions
- SyncFile can now get corresponding pair of path + open os-level fd
- cleaned up: fd now means os-level fd, f means python-file-like object
- fixed a caller of SaveFile
first time borg info is invoked on a borg 1.1 repo, it can take
a rather long time computing and caching some stats values for
1.1 archives, which borg 1.2 archives have in their archive
metadata structure. be patient, esp. if you have lots of old
archives.
following invocations are much faster.
the .get() like behaviour (== returning the value) was missing.
it's still not 100% like dict.setdefault, because there is no
default value None. but None doesn't make sense here, because we
usually need a N-tuple matching the hash table's value format.
note: this "bug" (or unusual implementation) was without consequences,
because hashindex.setdefault is not used anywhere in borg, so
it was also not used in a wrong way anywhere.
https://docs.python.org/3/library/stdtypes.html#dict.setdefault
docs:borg init: explain the encryption modes better
The documentation for borg init was not structured logically:
1. The topic is switched from the general discussion of `borg init`
to the discussion of encryption modes without a title.
2. Obscure technical details (chunking, id generation etc) were
above the high-level overview and other key information.
