No TERMIOS2 on PowerPC platforms

[bobpaul]

This builds and runs fun on PPC, PPC64, and PPC64LE, but I had to patch the CMakeLists.txt with:

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 4fe0ea2..0ddb3a9 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -68,8 +68,6 @@ else()
                 ${CMAKE_SOURCE_DIR}/vendor/libserialport/linux_termios.c)
         target_compile_definitions(libblisp_obj PRIVATE
                 LIBSERIALPORT_ATBUILD
-                HAVE_TERMIOS2_SPEED
-                HAVE_STRUCT_TERMIOS2
                 HAVE_DECL_BOTHER
                 "SP_API=__attribute__((visibility(\"default\")))"
                 "SP_PRIV=__attribute__((visibility(\"hidden\")))")

I'm not sure the proper way to make this conditional without simply introducing a manual override (ex maybe -DUSE_TERMIOS removes these).

[Ralim]

I'm not against a manual override + note in the readme that for PowerPC its required?

[robertlipe]

If one wanted to fix this well adjust the CMake code to test for it, autoconf style (sigh):

include(CheckCXXSourceCompiles)

# Check for termios2/TCGETS2
check_cxx_source_compiles("
    #include <asm/termios.h>
    int main() {
        struct termios2 tty;
        ioctl(0, TCGETS2&tty);
        return 0;
    }
" HAVE_TERMIOS2)

if(HAVE_TERMIOS2)
    message(STATUS "termios2 found")
    add_compile_definitions(USE_TERMIOS2)
else()
    message(STATUS "termios2 not found, using standard termios")
endif()

Given how extinct PPC is (sorry) this would be upon you to integrate, test, and argue into the tree that slowing it down for everyone else is worthwhile.

As large as the PPC user base isn't, I'd say Ralim's solution is the most practical one here. Please provide a PR against https://github.com/pine64/blisp/blob/master/README.md