- Prefer Sleep(1) over sched_yield() for pre-Vista thread yield.
On Windows sched_yield is often implemented as Sleep(0) which only
yields to threads of highest priority to current priority. However,
during libcurl initialization if there is thread contention then it's
possible that there is a wait for a different library or OS thread of
a lesser priority and then the yield is not effective during that time.
On the other hand Sleep(1) will wait the minimum time slice which is
usually like 15ms or more.
Prior to this change 2c4bfef removed sched_yield detection on Windows,
which effectively removed the yield in the spin lock, and therefore this
change restores the yield but in a different way.
For Windows Vista and later we use SRW locks and do not have this issue.
Ref: https://github.com/curl/curl/pull/16037#issuecomment-2600161764
Ref: https://devblogs.microsoft.com/oldnewthing/20051004-09/?p=33923
Closes https://github.com/curl/curl/pull/16048
Instead of redefining the `inline` keyword, introduce curl's own
`CURL_INLINE` macro and set it depending on the compiler's capabilities,
or use its value set via custom C flags.
Also keep honoring a custom `inline` macro, if set.
Closes#15523
Aka "jumbo" or "amalgamation" builds. It means to compile all sources
per target as a single C source. This is experimental.
You can enable it by passing `-DCMAKE_UNITY_BUILD=ON` to cmake.
It requires CMake 3.16 or newer.
It makes builds (much) faster, allows for better optimizations and tends
to promote less ambiguous code.
Also add a new AppVeyor CI job and convert an existing one to use
"unity" mode (one MSVC, one MinGW), and enable it for one macOS CI job.
Fix related issues:
- add missing include guard to `easy_lock.h`.
- rename static variables and functions (and a macro) with names reused
across sources, or shadowed by local variables.
- add an `#undef` after use.
- add a missing `#undef` before use.
- move internal definitions from `ftp.h` to `ftp.c`.
- `curl_memory.h` fixes to make it work when included repeatedly.
- stop building/linking curlx bits twice for a static-mode curl tool.
These caused doubly defined symbols in unity builds.
- silence missing extern declarations compiler warning for ` _CRT_glob`.
- fix extern declarations for `tool_freq` and `tool_isVistaOrGreater`.
- fix colliding static symbols in debug mode: `debugtime()` and
`statename`.
- rename `ssl_backend_data` structure to unique names for each
TLS-backend, along with the `ssl_connect_data` struct member
referencing them. This required adding casts for each access.
- add workaround for missing `[P]UNICODE_STRING` types in certain Windows
builds when compiling `lib/ldap.c`. To support "unity" builds, we had
to enable `SCHANNEL_USE_BLACKLISTS` for Schannel (a Windows
`schannel.h` option) _globally_. This caused an indirect inclusion of
Windows `schannel.h` from `ldap.c` via `winldap.h` to have it enabled
as well. This requires `[P]UNICODE_STRING` types, which is apperantly
not defined automatically (as seen with both MSVS and mingw-w64).
This patch includes `<subauth.h>` to fix it.
Ref: https://github.com/curl/curl/runs/13987772013
Ref: https://dev.azure.com/daniel0244/curl/_build/results?buildId=15827&view=logs&jobId=2c9f582d-e278-56b6-4354-f38a4d851906&j=2c9f582d-e278-56b6-4354-f38a4d851906&t=90509b00-34fa-5a81-35d7-5ed9569d331c
- tweak unity builds to compile `lib/memdebug.c` separately in memory
trace builds to avoid PP confusion.
- force-disable unity for test programs.
- do not compile and link libcurl sources to libtests _twice_ when libcurl
is built in static mode.
KNOWN ISSUES:
- running tests with unity builds may fail in cases.
- some build configurations/env may not compile in unity mode. E.g.:
https://ci.appveyor.com/project/curlorg/curl/builds/47230972/job/51wfesgnfuauwl8q#L250
Ref: https://github.com/libssh2/libssh2/issues/1034
Ref: https://cmake.org/cmake/help/latest/prop_tgt/UNITY_BUILD.html
Ref: https://en.wikipedia.org/wiki/Unity_buildCloses#11095
- 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
The Intel compiler tries to look like GCC *and* clang *and* it lies in
its __has_builtin() function (returns true when it should return false),
so override it.
Reported-by: Matthew Thompson
Fixes#9081Closes#9144
To work with more compilers without requiring separate libs to
link. Like with gcc-12 for RISC-V on Linux.
Reported-by: Adam Sampson
Fixes#9055Closes#9061
clang 14 warns about its use. It is being deprecated by the working
group for the programming language C: "The macro ATOMIC_VAR_INIT is
basically useless for the purpose for which it was designed"
Ref: https://www.open-std.org/jtc1/sc22/wg14/www/docs/n2886.htm
Reported-by: Tatsuhiro Tsujikawa
Fixes#9041Closes#9042
