Move timeval calculation functions into their own file.

git-svn-id: file:///home/lennart/svn/public/pulseaudio/trunk@926 fefdeb5f-60dc-0310-8127-8f9354f1896f

src/polyp/timeval.c

@@ -0,0 +1,142 @@
+/* $Id$ */
+
+/***
+  This file is part of polypaudio.
+ 
+  polypaudio 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.
+ 
+  polypaudio 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 polypaudio; if not, write to the Free Software
+  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
+  USA.
+***/
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <assert.h>
+#include <stddef.h>
+#include <sys/time.h>
+
+#ifdef HAVE_WINDOWS_H
+#include <windows.h>
+#endif
+
+#include "../polypcore/winsock.h"
+
+#include "timeval.h"
+
+struct timeval *pa_gettimeofday(struct timeval *tv) {
+#ifdef HAVE_GETTIMEOFDAY
+    assert(tv);
+    
+    return gettimeofday(tv, NULL) < 0 ? NULL : tv;
+#elif defined(OS_IS_WIN32)
+    /*
+     * Copied from implementation by Steven Edwards (LGPL).
+     * Found on wine mailing list.
+     */
+
+#if defined(_MSC_VER) || defined(__BORLANDC__)
+#define EPOCHFILETIME (116444736000000000i64)
+#else
+#define EPOCHFILETIME (116444736000000000LL)
+#endif
+
+    FILETIME        ft;
+    LARGE_INTEGER   li;
+    __int64         t;
+
+    assert(tv);
+
+    GetSystemTimeAsFileTime(&ft);
+    li.LowPart  = ft.dwLowDateTime;
+    li.HighPart = ft.dwHighDateTime;
+    t  = li.QuadPart;       /* In 100-nanosecond intervals */
+    t -= EPOCHFILETIME;     /* Offset to the Epoch time */
+    t /= 10;                /* In microseconds */
+    tv->tv_sec  = (long)(t / 1000000);
+    tv->tv_usec = (long)(t % 1000000);
+
+    return tv;
+#else
+#error "Platform lacks gettimeofday() or equivalent function."
+#endif
+}
+
+pa_usec_t pa_timeval_diff(const struct timeval *a, const struct timeval *b) {
+    pa_usec_t r;
+    assert(a && b);
+
+    /* Check which whan is the earlier time and swap the two arguments if reuqired. */
+    if (pa_timeval_cmp(a, b) < 0) {
+        const struct timeval *c;
+        c = a;
+        a = b;
+        b = c;
+    }
+
+    /* Calculate the second difference*/
+    r = ((pa_usec_t) a->tv_sec - b->tv_sec)* 1000000;
+
+    /* Calculate the microsecond difference */
+    if (a->tv_usec > b->tv_usec)
+        r += ((pa_usec_t) a->tv_usec - b->tv_usec);
+    else if (a->tv_usec < b->tv_usec)
+        r -= ((pa_usec_t) b->tv_usec - a->tv_usec);
+
+    return r;
+}
+
+int pa_timeval_cmp(const struct timeval *a, const struct timeval *b) {
+    assert(a && b);
+
+    if (a->tv_sec < b->tv_sec)
+        return -1;
+
+    if (a->tv_sec > b->tv_sec)
+        return 1;
+
+    if (a->tv_usec < b->tv_usec)
+        return -1;
+
+    if (a->tv_usec > b->tv_usec)
+        return 1;
+
+    return 0;
+}
+
+pa_usec_t pa_timeval_age(const struct timeval *tv) {
+    struct timeval now;
+    assert(tv);
+    
+    return pa_timeval_diff(pa_gettimeofday(&now), tv);
+}
+
+struct timeval* pa_timeval_add(struct timeval *tv, pa_usec_t v) {
+    unsigned long secs;
+    assert(tv);
+    
+    secs = (v/1000000);
+    tv->tv_sec += (unsigned long) secs;
+    v -= secs*1000000;
+
+    tv->tv_usec += v;
+
+    /* Normalize */
+    while (tv->tv_usec >= 1000000) {
+        tv->tv_sec++;
+        tv->tv_usec -= 1000000;
+    }
+
+    return tv;
+}