graphics/sane-backends: fix build with clang 15
During an exp-run for llvm 15 (see bug 265425), it turned out that
graphics/sane-backends failed to build with clang 15:
jpegtopdf.c:204:5: error: incompatible pointer to integer conversion assigning to 'long' from 'char *(int, int)' [-Wint-conversion]
tz = timezone;
^ ~~~~~~~~
scanimage.c:1248:42: warning: call to undeclared function 'basename'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
png_set_iCCP(*png_ptr, *info_ptr, basename(icc_profile), PNG_COMPRESSION_TYPE_BASE, icc_buffer, icc_size);
^
scanimage.c:1248:42: error: incompatible integer to pointer conversion passing 'int' to parameter of type 'png_const_charp' (aka 'const char *') [-Wint-conversion]
png_set_iCCP(*png_ptr, *info_ptr, basename(icc_profile), PNG_COMPRESSION_TYPE_BASE, icc_buffer, icc_size);
^~~~~~~~~~~~~~~~~~~~~The jpegtopdf error is because 'timezone' as a global external variable
does not exist on FreeBSD: it is a glibc-ism. Use struct tm's tm_gmtoff
field instead, which also has its sign reversed from the glibc global.
The scanimage error is because basename(3) is used without including
<libgen.h>. With glibc, basename() is declared in both string.h and
libgen.h, where the former gives you the GNU specific variant, and the
latter the POSIX variant.
PR: 268771
Approved by: vvd@unislabs.com (maintainer)
MFH: 2023Q1