lib: set more flags in config-win32.h

[vszakats]

The goal is to add any flag that affect the created binary, to get in sync with the ones built with CMake and autotools.

I took these flags from curl-for-win [0], where they've been tested with mingw-w64 and proven to work well.

This patch brings them to curl as follows:

• Enable unconditionally those force-enabled via CMake/WindowsCache.cmake:

  • HAVE_SETJMP_H
  • HAVE_STRING_H
  • HAVE_SIGNAL (CMake equivalent is HAVE_SIGNAL_FUNC)

• Expand existing guards with mingw-w64:

  • HAVE_STDBOOL_H
  • HAVE_BOOL_T

• Enable Win32 API functions for Windows Vista and later:

  • HAVE_INET_NTOP
  • HAVE_INET_PTON

• Set sizes, if not already set:

  • SIZEOF_OFF_T = 8
  • _FILE_OFFSET_BITS = 64 when USE_WIN32_LARGE_FILES is set,
    and using mingw-w64.

• Add the remaining for mingw-w64 only. Feel free to expand as desired:

  • HAVE_LIBGEN_H
  • HAVE_FTRUNCATE
  • HAVE_BASENAME
  • HAVE_STRTOK_R

Future TODOs:

• HAVE_SIGNAL has a different meaning in CMake. It's enabled when both the signal() function and the SIGALRM macro are found. In autotools and this header, it means the function only. For the function alone, CMake uses HAVE_SIGNAL_FUNC.

[0] https://github.com/curl/curl-for-win/blob/c9b9a5f273c94c73d2b565ee892c4dff0ca97a8c/curl-m32.sh#L53-L58

Closes #xxxx

[vszakats]

The AppVeyor CI job failure is unrelated:

TESTFAIL: These test cases failed: 1275
test 1275...[Verify capital letters after period in markdown files]

https://ci.appveyor.com/project/curlorg/curl/builds/45050447/job/odv664nav6sytial#L7280

[bagder]

The AppVeyor CI job failure is unrelated:

Wow, that was a spectacularly weird error!

[piekarpr]

@bagder, @vszakats , building libcurl for windows (64bit with VS2022), it appears sizeof(off_t) is equal to 4 and not 8. Looking at the CRT's types.h file (Windows 10 SDK 10.0.19041.0), off_t is defined as
typedef long _off_t; // file offset value
where "long" is 32 bit in Windows builds.

After updating from 7.84.0 to 7.86.0, a static_assert in our code was triggered, which we added among others to make sure libcurl was not misconfigured for the target:
static_assert(SIZEOF_OFF_T == sizeof(off_t), "off_t type size not defined correctly");

I was also surprised to find that off_t and SIZEOF_OFF_T appear to be not used anywhere inside libcurl, and I was wondering why it was added in the first place if not used.

[vszakats]

@PeterPiekarski Thanks for your report. Before this patch this macro settled on 4 by default, indeed. I didn't recognize this type is CRT-dependent. So maybe this method would be better by limiting this line to MinGW:

#if defined(__MINGW32__)
#  define SIZEOF_OFF_T 8
#endif

As a temporary workaround you can use -DSIZEOF_OFF_T=4.

Oops, forgot to add: This value is used in curl, in lib/version.c and src/tool_cb_see.c.