https://best.openssf.org/Compiler-Hardening-Guides/Compiler-Options-Hardening-Guide-for-C-and-C++.html
as of 2023-11-29 [1].
Enable new recommended warnings (except `-Wsign-conversion`):
- enable `-Wformat=2` for clang (in both cmake and autotools).
- add `CURL_PRINTF()` internal attribute and mark functions accepting
printf arguments with it. This is a copy of existing
`CURL_TEMP_PRINTF()` but using `__printf__` to make it compatible
with redefinting the `printf` symbol:
https://gcc.gnu.org/onlinedocs/gcc-3.0.4/gcc_5.html#SEC94
- fix `CURL_PRINTF()` and existing `CURL_TEMP_PRINTF()` for
mingw-w64 and enable it on this platform.
- enable `-Wimplicit-fallthrough`.
- enable `-Wtrampolines`.
- add `-Wsign-conversion` commented with a FIXME.
- cmake: enable `-pedantic-errors` the way we do it with autotools.
Follow-up to d5c0351055#2747
- lib/curl_trc.h: use `CURL_FORMAT()`, this also fixes it to enable format
checks. Previously it was always disabled due to the internal `printf`
macro.
Fix them:
- fix bug where an `set_ipv6_v6only()` call was missed in builds with
`--disable-verbose` / `CURL_DISABLE_VERBOSE_STRINGS=ON`.
- add internal `FALLTHROUGH()` macro.
- replace obsolete fall-through comments with `FALLTHROUGH()`.
- fix fallthrough markups: Delete redundant ones (showing up as
warnings in most cases). Add missing ones. Fix indentation.
- silence `-Wformat-nonliteral` warnings with llvm/clang.
- fix one `-Wformat-nonliteral` warning.
- fix new `-Wformat` and `-Wformat-security` warnings.
- fix `CURL_FORMAT_SOCKET_T` value for mingw-w64. Also move its
definition to `lib/curl_setup.h` allowing use in `tests/server`.
- lib: fix two wrongly passed string arguments in log outputs.
Co-authored-by: Jay Satiro
- fix new `-Wformat` warnings on mingw-w64.
[1] 56c0fde389/docs/Compiler-Hardening-Guides/Compiler-Options-Hardening-Guide-for-C-and-C%2B%2B.mdCloses#12489
Windows compilers define `_WIN32` automatically. Windows SDK headers
or build env defines `WIN32`, or we have to take care of it. The
agreement seems to be that `_WIN32` is the preferred practice here.
Make the source code rely on that to detect we're building for Windows.
Public `curl.h` was using `WIN32`, `__WIN32__` and `CURL_WIN32` for
Windows detection, next to the official `_WIN32`. After this patch it
only uses `_WIN32` for this. Also, make it stop defining `CURL_WIN32`.
There is a slight chance these break compatibility with Windows
compilers that fail to define `_WIN32`. I'm not aware of any obsolete
or modern compiler affected, but in case there is one, one possible
solution is to define this macro manually.
grepping for `WIN32` remains useful to discover Windows-specific code.
Also:
- extend `checksrc` to ensure we're not using `WIN32` anymore.
- apply minor formatting here and there.
- delete unnecessary checks for `!MSDOS` when `_WIN32` is present.
Co-authored-by: Jay Satiro
Reviewed-by: Daniel Stenberg
Closes#12376
- they are mostly pointless in all major jurisdictions
- many big corporations and projects already don't use them
- saves us from pointless churn
- git keeps history for us
- the year range is kept in COPYING
checksrc is updated to allow non-year using copyright statements
Closes#10205
- Load Windows system libraries secur32 and iphlpapi beforehand, so
that libcurl's repeated global init/cleanup only increases/decreases
the library's refcount rather than causing it to load/unload.
Assisted-by: Marc Hoersken
Closes https://github.com/curl/curl/pull/9412
Referring to Daniel's article [1], making the init function thread-safe
was the last bit to make libcurl thread-safe as a whole. So the name of
the feature may as well be the more concise 'threadsafe', also telling
the story that libcurl is now fully thread-safe, not just its init
function. Chances are high that libcurl wants to remain so in the
future, so there is little likelihood of ever needing any other distinct
`threadsafe-<name>` feature flags.
For consistency we also shorten `CURL_VERSION_THREADSAFE_INIT` to
`CURL_VERSION_THREADSAFE`, update its description and reference libcurl's
thread safety documentation.
[1]: https://daniel.haxx.se/blog/2022/06/08/making-libcurl-init-more-thread-safe/
Reviewed-by: Daniel Stenberg
Reviewed-by: Jay Satiro
Closes#8989
This flag can be used to make sure that curl_global_init() is
thread-safe.
This can be useful for libraries that can't control what other
dependencies are doing with Curl.
Closes#8680
