Modules/timemodule.c

/***********************************************************
Copyright 1991-1995 by Stichting Mathematisch Centrum, Amsterdam,
The Netherlands.

                        All Rights Reserved

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documentation for any purpose and without fee is hereby granted,
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/* Time module */

#include "Python.h"

#ifdef HAVE_SELECT
#include "mymath.h"
#endif

#ifdef macintosh
#include <time.h>
#else
#include <sys/types.h>
#endif

#ifdef QUICKWIN
#include <io.h>
#endif

#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif

#ifdef HAVE_SELECT
#include "myselect.h"
#else
#include "mytime.h"
#endif

#ifdef HAVE_FTIME
#include <sys/timeb.h>
#ifndef MS_WINDOWS
extern int ftime();
#endif /* MS_WINDOWS */
#endif /* HAVE_FTIME */

#ifdef __WATCOMC__
#include <i86.h>
#else
#ifdef MS_WINDOWS
#include <windows.h>
#ifdef MS_WIN16
/* These overrides not needed for Win32 */
#define timezone _timezone
#define tzname _tzname
#define daylight _daylight
#define altzone _altzone
#endif /* MS_WIN16 */
#endif /* MS_WINDOWS */
#endif /* !__WATCOMC__ */

/* Forward declarations */
static int floatsleep Py_PROTO((double));
static double floattime Py_PROTO(());

static PyObject *
time_time(self, args)
	PyObject *self;
	PyObject *args;
{
	double secs;
	if (!PyArg_NoArgs(args))
		return NULL;
	secs = floattime();
	if (secs == 0.0) {
		PyErr_SetFromErrno(PyExc_IOError);
		return NULL;
	}
	return PyFloat_FromDouble(secs);
}

#ifdef HAVE_CLOCK

#ifndef CLOCKS_PER_SEC
#ifdef CLK_TCK
#define CLOCKS_PER_SEC CLK_TCK
#else
#define CLOCKS_PER_SEC 1000000
#endif
#endif

static PyObject *
time_clock(self, args)
	PyObject *self;
	PyObject *args;
{
	if (!PyArg_NoArgs(args))
		return NULL;
	return PyFloat_FromDouble(((double)clock()) / CLOCKS_PER_SEC);
}
#endif /* HAVE_CLOCK */

static PyObject *
time_sleep(self, args)
	PyObject *self;
	PyObject *args;
{
	double secs;
	if (!PyArg_Parse(args, "d", &secs))
		return NULL;
	Py_BEGIN_ALLOW_THREADS
		if (floatsleep(secs) != 0) {
			Py_BLOCK_THREADS
				return NULL;
		}
	Py_END_ALLOW_THREADS
		Py_INCREF(Py_None);
	return Py_None;
}

static PyObject *
time_convert(when, function)
	time_t when;
	struct tm * (*function) Py_PROTO((const time_t *));
{
	struct tm *p;
	errno = 0;
	p = function(&when);
	if (p == NULL) {
#ifdef EINVAL
		if (errno == 0)
			errno = EINVAL;
#endif
		return PyErr_SetFromErrno(PyExc_IOError);
	}
	return Py_BuildValue("(iiiiiiiii)",
			     p->tm_year + 1900,
			     p->tm_mon + 1,        /* Want January == 1 */
			     p->tm_mday,
			     p->tm_hour,
			     p->tm_min,
			     p->tm_sec,
			     (p->tm_wday + 6) % 7, /* Want Monday == 0 */
			     p->tm_yday + 1,       /* Want January, 1 == 1 */
			     p->tm_isdst);
}

static PyObject *
time_gmtime(self, args)
	PyObject *self;
	PyObject *args;
{
	double when;
	if (!PyArg_Parse(args, "d", &when))
		return NULL;
	return time_convert((time_t)when, gmtime);
}

static PyObject *
time_localtime(self, args)
	PyObject *self;
	PyObject *args;
{
	double when;
	if (!PyArg_Parse(args, "d", &when))
		return NULL;
	return time_convert((time_t)when, localtime);
}

static int
gettmarg(args, p)
	PyObject *args;
	struct tm *p;
{
	if (!PyArg_Parse(args, "(iiiiiiiii)",
			 &p->tm_year,
			 &p->tm_mon,
			 &p->tm_mday,
			 &p->tm_hour,
			 &p->tm_min,
			 &p->tm_sec,
			 &p->tm_wday,
			 &p->tm_yday,
			 &p->tm_isdst))
		return 0;
	if (p->tm_year >= 1900)
		p->tm_year -= 1900;
	p->tm_mon--;
	p->tm_wday = (p->tm_wday + 1) % 7;
	p->tm_yday--;
	return 1;
}

#ifdef HAVE_STRFTIME
static PyObject *
time_strftime(self, args)
	PyObject *self;
	PyObject *args;
{
	struct tm buf;
	const char *fmt;
	char *outbuf = 0;
	int i;

	if (!PyArg_ParseTuple(args, "s(iiiiiiiii)",
			      &fmt,
			      &(buf.tm_year),
			      &(buf.tm_mon),
			      &(buf.tm_mday),
			      &(buf.tm_hour),
			      &(buf.tm_min),
			      &(buf.tm_sec),
			      &(buf.tm_wday),
			      &(buf.tm_yday),
			      &(buf.tm_isdst)))
		return NULL;
	if (buf.tm_year >= 1900)
		buf.tm_year -= 1900;
	buf.tm_mon--;
	buf.tm_wday = (buf.tm_wday + 1) % 7;
	buf.tm_yday--;
	/* I hate these functions that presume you know how big the output
	 * will be ahead of time...
	 */
	for (i = 1024 ; i <= 8192 ; i += 1024) {
		outbuf = malloc(i);
		if (outbuf == NULL) {
			return PyErr_NoMemory();
		}
		if (strftime(outbuf, i-1, fmt, &buf) != 0) {
			PyObject *ret;
			ret = PyString_FromString(outbuf);
			free(outbuf);
			return ret;
		}
		free(outbuf);
	}
	PyErr_SetString(PyExc_ValueError,
			"bad strftime format or result too big");
	return NULL;
}
#endif /* HAVE_STRFTIME */

static PyObject *
time_asctime(self, args)
	PyObject *self;
	PyObject *args;
{
	struct tm buf;
	char *p;
	if (!gettmarg(args, &buf))
		return NULL;
	p = asctime(&buf);
	if (p[24] == '\n')
		p[24] = '\0';
	return PyString_FromString(p);
}

static PyObject *
time_ctime(self, args)
	PyObject *self;
	PyObject *args;
{
	double dt;
	time_t tt;
	char *p;
	if (!PyArg_Parse(args, "d", &dt))
		return NULL;
	tt = (time_t)dt;
	p = ctime(&tt);
	if (p[24] == '\n')
		p[24] = '\0';
	return PyString_FromString(p);
}

static PyObject *
time_mktime(self, args)
	PyObject *self;
	PyObject *args;
{
	struct tm buf;
	time_t tt;
	tt = time(&tt);
	buf = *localtime(&tt);
	if (!gettmarg(args, &buf))
		return NULL;
	tt = mktime(&buf);
	if (tt == (time_t)(-1)) {
		PyErr_SetString(PyExc_OverflowError,
                                "mktime argument out of range");
		return NULL;
	}
	return PyFloat_FromDouble((double)tt);
}

static PyMethodDef time_methods[] = {
	{"time",	time_time},
#ifdef HAVE_CLOCK
	{"clock",	time_clock},
#endif
	{"sleep",	time_sleep},
	{"gmtime",	time_gmtime},
	{"localtime",	time_localtime},
	{"asctime",	time_asctime},
	{"ctime",	time_ctime},
	{"mktime",	time_mktime},
#ifdef HAVE_STRFTIME
	{"strftime",	time_strftime, 1},
#endif
	{NULL,		NULL}		/* sentinel */
};

static void
ins(d, name, v)
	PyObject *d;
	char *name;
	PyObject *v;
{
	if (v == NULL)
		Py_FatalError("Can't initialize time module -- NULL value");
	if (PyDict_SetItemString(d, name, v) != 0)
		Py_FatalError(
		"Can't initialize time module -- PyDict_SetItemString failed");
	Py_DECREF(v);
}

void
inittime()
{
	PyObject *m, *d;
	m = Py_InitModule("time", time_methods);
	d = PyModule_GetDict(m);
#ifdef HAVE_TZNAME
	tzset();
	ins(d, "timezone", PyInt_FromLong((long)timezone));
#ifdef HAVE_ALTZONE
	ins(d, "altzone", PyInt_FromLong((long)altzone));
#else
	ins(d, "altzone", PyInt_FromLong((long)timezone-3600));
#endif
	ins(d, "daylight", PyInt_FromLong((long)daylight));
	ins(d, "tzname", Py_BuildValue("(zz)", tzname[0], tzname[1]));
#else /* !HAVE_TZNAME */
#if HAVE_TM_ZONE
	{
#define YEAR ((time_t)((365 * 24 + 6) * 3600))
		time_t t;
		struct tm *p;
		long winterzone, summerzone;
		char wintername[10], summername[10];
		/* XXX This won't work on the southern hemisphere.
		  XXX Anybody got a better idea? */
		t = (time((time_t *)0) / YEAR) * YEAR;
		p = localtime(&t);
		winterzone = -p->tm_gmtoff;
		strncpy(wintername, p->tm_zone ? p->tm_zone : "   ", 9);
		wintername[9] = '\0';
		t += YEAR/2;
		p = localtime(&t);
		summerzone = -p->tm_gmtoff;
		strncpy(summername, p->tm_zone ? p->tm_zone : "   ", 9);
		summername[9] = '\0';
		ins(d, "timezone", PyInt_FromLong(winterzone));
		ins(d, "altzone", PyInt_FromLong(summerzone));
		ins(d, "daylight",
                    PyInt_FromLong((long)(winterzone != summerzone)));
		ins(d, "tzname",
                    Py_BuildValue("(zz)", wintername, summername));
	}
#endif /* HAVE_TM_ZONE */
#endif /* !HAVE_TZNAME */
	if (PyErr_Occurred())
		Py_FatalError("Can't initialize time module");
}


/* Implement floattime() for various platforms */

static double
floattime()
{
	/* There are three ways to get the time:
	  (1) gettimeofday() -- resolution in microseconds
	  (2) ftime() -- resolution in milliseconds
	  (3) time() -- resolution in seconds
	  In all cases the return value is a float in seconds.
	  Since on some systems (e.g. SCO ODT 3.0) gettimeofday() may
	  fail, so we fall back on ftime() or time().
	  Note: clock resolution does not imply clock accuracy! */
#ifdef HAVE_GETTIMEOFDAY
	{
		struct timeval t;
#ifdef GETTIMEOFDAY_NO_TZ
		if (gettimeofday(&t) == 0)
			return (double)t.tv_sec + t.tv_usec*0.000001;
#else /* !GETTIMEOFDAY_NO_TZ */
		if (gettimeofday(&t, (struct timezone *)NULL) == 0)
			return (double)t.tv_sec + t.tv_usec*0.000001;
#endif /* !GETTIMEOFDAY_NO_TZ */
	}
#endif /* !HAVE_GETTIMEOFDAY */
	{
#ifdef HAVE_FTIME
		struct timeb t;
		ftime(&t);
		return (double)t.time + (double)t.millitm * (double)0.001;
#else /* !HAVE_FTIME */
		time_t secs;
		time(&secs);
		return (double)secs;
#endif /* !HAVE_FTIME */
	}
}


/* Implement floatsleep() for various platforms.
   When interrupted (or when another error occurs), return -1 and
   set an exception; else return 0. */

static int
#ifdef MPW
floatsleep(double secs)
#else
	floatsleep(secs)
	double secs;
#endif /* MPW */
{
/* XXX Should test for MS_WIN32 first! */
#ifdef HAVE_SELECT
	struct timeval t;
	double frac;
	frac = fmod(secs, 1.0);
	secs = floor(secs);
	t.tv_sec = (long)secs;
	t.tv_usec = (long)(frac*1000000.0);
	if (select(0, (fd_set *)0, (fd_set *)0, (fd_set *)0, &t) != 0) {
		PyErr_SetFromErrno(PyExc_IOError);
		return -1;
	}
#else /* !HAVE_SELECT */
#ifdef macintosh
#define MacTicks	(* (long *)0x16A)
	long deadline;
	deadline = MacTicks + (long)(secs * 60.0);
	while (MacTicks < deadline) {
		if (PyErr_CheckSignals())
			return -1;
	}
#else /* !macintosh */
#ifdef __WATCOMC__
	/* XXX Can't interrupt this sleep */
	delay((int)(secs * 1000 + 0.5));  /* delay() uses milliseconds */
#else /* !__WATCOMC__ */
#ifdef MSDOS
	struct timeb t1, t2;
	double frac;
	extern double fmod Py_PROTO((double, double));
	extern double floor Py_PROTO((double));
	if (secs <= 0.0)
		return;
	frac = fmod(secs, 1.0);
	secs = floor(secs);
	ftime(&t1);
	t2.time = t1.time + (int)secs;
	t2.millitm = t1.millitm + (int)(frac*1000.0);
	while (t2.millitm >= 1000) {
		t2.time++;
		t2.millitm -= 1000;
	}
	for (;;) {
#ifdef QUICKWIN
		_wyield();
#endif
		if (PyErr_CheckSignals())
			return -1;
		ftime(&t1);
		if (t1.time > t2.time ||
		    t1.time == t2.time && t1.millitm >= t2.millitm)
			break;
	}
#else /* !MSDOS */
#ifdef MS_WIN32
	/* XXX Can't interrupt this sleep */
	Sleep((int)(secs*1000));
#else /* !MS_WIN32 */
	/* XXX Can't interrupt this sleep */
	sleep((int)secs);
#endif /* !MS_WIN32 */
#endif /* !MSDOS */
#endif /* !__WATCOMC__ */
#endif /* !macintosh */
#endif /* !HAVE_SELECT */
	return 0;
}