pjproject/pjlib/src/pj/os_timestamp_posix.c

143 lines
3.3 KiB
C

/* $Id$ */
/*
* Copyright (C)2003-2006 Benny Prijono <benny@prijono.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <pj/os.h>
#include <pj/errno.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <ctype.h>
#if defined(PJ_HAS_PENTIUM) && PJ_HAS_PENTIUM!=0 && \
defined(PJ_TIMESTAMP_USE_RDTSC) && PJ_TIMESTAMP_USE_RDTSC!=0 && \
defined(PJ_M_I386) && PJ_M_I386!=0 && \
defined(PJ_LINUX) && PJ_LINUX!=0
static int machine_speed_mhz;
static pj_timestamp machine_speed;
static __inline__ unsigned long long int rdtsc()
{
unsigned long long int x;
__asm__ volatile (".byte 0x0f, 0x31" : "=A" (x));
return x;
}
/* Determine machine's CPU MHz to get the counter's frequency.
*/
static int get_machine_speed_mhz()
{
FILE *strm;
char buf[512];
int len;
char *pos, *end;
PJ_CHECK_STACK();
/* Open /proc/cpuinfo and read the file */
strm = fopen("/proc/cpuinfo", "r");
if (!strm)
return -1;
len = fread(buf, 1, sizeof(buf), strm);
fclose(strm);
if (len < 1) {
return -1;
}
buf[len] = '\0';
/* Locate the MHz digit. */
pos = strstr(buf, "cpu MHz");
if (!pos)
return -1;
pos = strchr(pos, ':');
if (!pos)
return -1;
end = (pos += 2);
while (isdigit(*end)) ++end;
*end = '\0';
/* Return the Mhz part, and give it a +1. */
return atoi(pos)+1;
}
PJ_DEF(pj_status_t) pj_get_timestamp(pj_timestamp *ts)
{
if (machine_speed_mhz == 0) {
machine_speed_mhz = get_machine_speed_mhz();
if (machine_speed_mhz > 0) {
machine_speed.u64 = machine_speed_mhz * 1000000.0;
}
}
if (machine_speed_mhz == -1) {
ts->u64 = 0;
return -1;
}
ts->u64 = rdtsc();
return 0;
}
PJ_DEF(pj_status_t) pj_get_timestamp_freq(pj_timestamp *freq)
{
if (machine_speed_mhz == 0) {
machine_speed_mhz = get_machine_speed_mhz();
if (machine_speed_mhz > 0) {
machine_speed.u64 = machine_speed_mhz * 1000000.0;
}
}
if (machine_speed_mhz == -1) {
freq->u64 = 1; /* return 1 to prevent division by zero in apps. */
return -1;
}
freq->u64 = machine_speed.u64;
return 0;
}
#else
#include <sys/time.h>
#include <errno.h>
#define USEC_PER_SEC 1000000
PJ_DEF(pj_status_t) pj_get_timestamp(pj_timestamp *ts)
{
struct timeval tv;
if (gettimeofday(&tv, NULL) != 0) {
return PJ_RETURN_OS_ERROR(pj_get_native_os_error());
}
ts->u64 = tv.tv_sec;
ts->u64 *= USEC_PER_SEC;
ts->u64 += tv.tv_usec;
return PJ_SUCCESS;
}
PJ_DEF(pj_status_t) pj_get_timestamp_freq(pj_timestamp *freq)
{
freq->u32.hi = 0;
freq->u32.lo = USEC_PER_SEC;
return PJ_SUCCESS;
}
#endif