Build: Add very limited experimental CMake support.

This does *NOT* replace the Autotools-based build system in
the foreseeable future. See the comment in the beginning
of CMakeLists.txt.

So far this has been tested only on GNU/Linux but I commit
it anyway to make it easier for others to test. Since I
haven't played much with CMake before, it's likely that
there are things that have been done in a silly or wrong
way and need to be fixed.

1 files changed, 149 insertions, 0 deletions

diff --git a/cmake/tuklib_physmem.cmake b/cmake/tuklib_physmem.cmake
new file mode 100644
index 00000000..dc895a15
--- /dev/null
+++ b/cmake/tuklib_physmem.cmake
@@ -0,0 +1,149 @@
+#
+# tuklib_physmem.cmake - see tuklib_physmem.m4 for description and comments
+#
+# NOTE: Compared tuklib_physmem.m4, this lacks support for Tru64, IRIX, and
+# Linux sysinfo() (usually sysconf() is used on GNU/Linux).
+#
+# Author: Lasse Collin
+#
+# This file has been put into the public domain.
+# You can do whatever you want with this file.
+#
+
+include(${CMAKE_CURRENT_LIST_DIR}/tuklib_common.cmake)
+include(CheckCSourceCompiles)
+include(CheckIncludeFile)
+
+function(tuklib_physmem_internal_check)
+    if(CACHE{TUKLIB_PHYSMEM_DEFINITIONS})
+        return()
+    endif()
+
+    # Shortcut on Windows:
+    if(WIN32 OR CYGWIN)
+        # Nothing to do, the tuklib_physmem.c handles it.
+        set(TUKLIB_PHYSMEM_DEFINITIONS "" CACHE INTERNAL "")
+        return()
+    endif()
+
+    # Full check for special cases:
+    check_c_source_compiles("
+            #if defined(_WIN32) || defined(__CYGWIN__) || defined(__OS2__) \
+                || defined(__DJGPP__) || defined(__VMS) \
+                || defined(AMIGA) || defined(__AROS__) || defined(__QNX__)
+            int main(void) { return 0; }
+            #else
+            compile error
+            #endif
+        "
+        TUKLIB_PHYSMEM_SPECIAL)
+    if(TUKLIB_PHYSMEM_SPECIAL)
+        # Nothing to do, the tuklib_physmem.c handles it.
+        set(TUKLIB_PHYSMEM_DEFINITIONS "" CACHE INTERNAL "")
+        return()
+    endif()
+
+    # Look for AIX-specific solution before sysconf(), because the test
+    # for sysconf() will pass on AIX but won't actually work
+    # (sysconf(_SC_PHYS_PAGES) compiles but always returns -1 on AIX).
+    check_c_source_compiles("
+            #include <sys/systemcfg.h>
+            int main(void)
+            {
+                (void)_system_configuration.physmem;
+                return 0;
+            }
+        "
+        TUKLIB_PHYSMEM_AIX)
+    if(TUKLIB_PHYSMEM_AIX)
+        set(TUKLIB_PHYSMEM_DEFINITIONS "TUKLIB_PHYSMEM_AIX" CACHE INTERNAL "")
+        return()
+    endif()
+
+    # sysconf()
+    check_c_source_compiles("
+            #include <unistd.h>
+            int main(void)
+            {
+                long i;
+                i = sysconf(_SC_PAGESIZE);
+                i = sysconf(_SC_PHYS_PAGES);
+                return 0;
+            }
+        "
+        TUKLIB_PHYSMEM_SYSCONF)
+    if(TUKLIB_PHYSMEM_SYSCONF)
+        set(TUKLIB_PHYSMEM_DEFINITIONS "TUKLIB_PHYSMEM_SYSCONF"
+            CACHE INTERNAL "")
+        return()
+    endif()
+
+    # sysctl()
+    check_include_file(sys/param.h HAVE_SYS_PARAM_H)
+    if(HAVE_SYS_PARAM_H)
+        list(APPEND CMAKE_REQUIRED_DEFINITIONS -DHAVE_SYS_PARAM_H)
+    endif()
+
+    check_c_source_compiles("
+            #ifdef HAVE_SYS_PARAM_H
+            #   include <sys/param.h>
+            #endif
+            #include <sys/sysctl.h>
+            int main(void)
+            {
+                int name[2] = { CTL_HW, HW_PHYSMEM };
+                unsigned long mem;
+                size_t mem_ptr_size = sizeof(mem);
+                sysctl(name, 2, &mem, &mem_ptr_size, NULL, 0);
+                return 0;
+            }
+        "
+        TUKLIB_PHYSMEM_SYSCTL)
+    if(TUKLIB_PHYSMEM_SYSCTL)
+        if(HAVE_SYS_PARAM_H)
+            set(TUKLIB_PHYSMEM_DEFINITIONS
+                "HAVE_PARAM_H;TUKLIB_PHYSMEM_SYSCTL"
+                CACHE INTERNAL "")
+        else()
+            set(TUKLIB_PHYSMEM_DEFINITIONS
+                "TUKLIB_PHYSMEM_SYSCTL"
+                CACHE INTERNAL "")
+        endif()
+        return()
+    endif()
+
+    # HP-UX
+    check_c_source_compiles("
+            #include <sys/param.h>
+            #include <sys/pstat.h>
+            int main(void)
+            {
+                struct pst_static pst;
+                pstat_getstatic(&pst, sizeof(pst), 1, 0);
+                (void)pst.physical_memory;
+                (void)pst.page_size;
+                return 0;
+            }
+        "
+        TUKLIB_PHYSMEM_PSTAT_GETSTATIC)
+    if(TUKLIB_PHYSMEM_PSTAT_GETSTATIC)
+        set(TUKLIB_PHYSMEM_DEFINITIONS "TUKLIB_PHYSMEM_PSTAT_GETSTATIC"
+            CACHE INTERNAL "")
+        return()
+    endif()
+endfunction()
+
+function(tuklib_physmem TARGET_OR_ALL)
+    message(STATUS "Checking how to detect the amount of physical memory")
+
+    tuklib_physmem_internal_check()
+
+    if(NOT DEFINED CACHE{TUKLIB_PHYSMEM_DEFINITIONS})
+        set(TUKLIB_PHYSMEM_FOUND 0 PARENT_SCOPE)
+        message(WARNING
+                "No method to detect the amount of physical memory was found")
+    else()
+        set(TUKLIB_PHYSMEM_FOUND 1 PARENT_SCOPE)
+        tuklib_add_definitions(${TARGET_OR_ALL} ${TUKLIB_PHYSMEM_DEFINITIONS})
+    endif()
+endfunction()