/* EINA - EFL data type library
 * Copyright (C) 2007-2008 Jorge Luis Zapata Muga
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library;
 * if not, see <http://www.gnu.org/licenses/>.
 */

#ifdef HAVE_CONFIG_H
# include "config.h"
#endif

#ifdef EFL_HAVE_PTHREAD
# ifdef _WIN32
#  define WIN32_LEAN_AND_MEAN
#  include <windows.h>
# elif defined (__SUNPRO_C)
#  include <unistd.h>
# elif defined (__FreeBSD__) || defined (__OpenBSD__) || defined (__NetBSD__) || defined (__DragonFly__) || defined (__MacOSX__)
#  include <unistd.h>
#  include <sys/sysctl.h>
# elif defined (__linux__)
#  define _GNU_SOURCE
#  include <sched.h>
# endif
# include <pthread.h>

# define TH_MAX 8
#endif

#include <stdio.h>
#include <string.h>
#include <errno.h>

#include "eina_cpu.h"

/*============================================================================*
 *                                  Local                                     *
 *============================================================================*/

/* FIXME this ifdefs should be replaced */
#if defined(__i386__) || defined(__x86_64__)
/* We save ebx and restore it to be PIC compatible */
static inline void _x86_cpuid(int op, int *a, int *b, int *c, int *d)
{
	asm volatile(
#if defined(__x86_64__)
		"pushq %%rbx      \n\t" /* save %ebx */
#else
		"pushl %%ebx      \n\t" /* save %ebx */
#endif
		"cpuid            \n\t"
		"movl %%ebx, %1   \n\t" /* save what cpuid just put in %ebx */
#if defined(__x86_64__)
		"popq %%rbx       \n\t" /* restore the old %ebx */
#else
		"popl %%ebx       \n\t" /* restore the old %ebx */
#endif
		: "=a"(*a), "=r"(*b), "=c"(*c), "=d"(*d)
		: "a"(op)
		: "cc");
}

void _x86_simd(Eina_Cpu_Features *features)
{
	int a, b, c, d;

	_x86_cpuid(1, &a, &b, &c, &d);
	/*
	 * edx
	 * 18 = PN (Processor Number)
	 * 19 = CLFlush (Cache Line Flush)
	 * 23 = MMX
	 * 25 = SSE
	 * 26 = SSE2
	 * 28 = HTT (Hyper Threading)
	 * ecx
	 * 0 = SSE3
	 */
	if ((d >> 23) & 1)
		*features |= EINA_CPU_MMX;
	if ((d >> 25) & 1)
		*features |= EINA_CPU_SSE;
	if ((d >> 26) & 1)
		*features |= EINA_CPU_SSE2;
	if (c & 1)
		*features |= EINA_CPU_SSE3;
}
#endif

/*============================================================================*
 *                                 Global                                     *
 *============================================================================*/

/*============================================================================*
 *                                   API                                      *
 *============================================================================*/

/* FIXME the features checks should be called when this function is called?
 * or make it static by doing eina_cpu_init() and return a local var
 */
/**
 *
 * @return
 */
EAPI Eina_Cpu_Features eina_cpu_features_get(void)
{
	Eina_Cpu_Features ecf = 0;
#if defined(__i386__) || defined(__x86_64__)
	_x86_simd(&ecf);
#endif
	return ecf;
}

EAPI int eina_cpu_count(void)
{
#ifdef EFL_HAVE_PTHREAD

# if   defined (_WIN32)
   SYSTEM_INFO sysinfo;

   GetSystemInfo(&sysinfo);
   return sysinfo.dwNumberOfProcessors;

# elif defined (__SUNPRO_C)
   /*
    * _SC_NPROCESSORS_ONLN: number of processors that are online, that
                            is available when sysconf is called. The number
                            of cpu can change by admins.
    * _SC_NPROCESSORS_CONF: maximum number of processors that are available
                            to the current OS instance. That number can be
                            change after a reboot.
    * _SC_NPROCESSORS_MAX : maximum number of processors that are on the
                            motherboard.
    */
   return sysconf(_SC_NPROCESSORS_ONLN);

# elif defined (__FreeBSD__) || defined (__OpenBSD__) || defined (__NetBSD__) || defined (__DragonFly__) || defined (__MacOSX__)
   int    mib[4];
   size_t len;
   int    cpus;

   mib[0] = CTL_HW;
   mib[1] = HM_NCPU;
   sysctl(mib, 2, &cpus, &len, NULL, 0);
   if (cpus < 1)
     {
	mib[1] = HW_NCPU;
	sysctl(mib, 2, &cpus, &len, NULL, 0);
	if (cpus < 1)
	  cpus = 1;
     }
   return cpus;

# elif defined (__linux__)
   cpu_set_t cpu;
   int i;
   static int cpus = 0;

   if (cpus != 0) return cpus;

   CPU_ZERO(&cpu);
   if (sched_getaffinity(0, sizeof(cpu), &cpu) != 0)
     {
	fprintf(stderr, "[Eina] could not get cpu affinity: %s\n", strerror(errno));
	return 1;
     }
   for (i = 0; i < TH_MAX; i++)
     {
	if (CPU_ISSET(i, &cpu)) cpus = i + 1;
	else break;
     }
   return cpus;

# else
#  error "eina_cpu_count() error: Platform not supported"
# endif
#else
   return 1;
#endif
}