// sched.c - execute commands at scheduled times

//

// © Portions Copyright (c) Symbian Software Ltd 2007. All rights reserved.

//

/*

 * This file is part of zsh, the Z shell.

 *

 * Copyright (c) 1992-1997 Paul Falstad

 * All rights reserved.

 *

 * Permission is hereby granted, without written agreement and without

 * license or royalty fees, to use, copy, modify, and distribute this

 * software and to distribute modified versions of this software for any

 * purpose, provided that the above copyright notice and the following

 * two paragraphs appear in all copies of this software.

 *

 * In no event shall Paul Falstad or the Zsh Development Group be liable

 * to any party for direct, indirect, special, incidental, or consequential

 * damages arising out of the use of this software and its documentation,

 * even if Paul Falstad and the Zsh Development Group have been advised of

 * the possibility of such damage.

 *

 * Paul Falstad and the Zsh Development Group specifically disclaim any

 * warranties, including, but not limited to, the implied warranties of

 * merchantability and fitness for a particular purpose.  The software

 * provided hereunder is on an "as is" basis, and Paul Falstad and the

 * Zsh Development Group have no obligation to provide maintenance,

 * support, updates, enhancements, or modifications.

 *

 */

#include "sched.mdh"

#include "sched.pro"

#ifdef __SYMBIAN32__

#ifdef __WINSCW__

#pragma warn_unusedarg off

#pragma warn_possunwant off

#endif//__WINSCW__

#endif//__SYMBIAN32__

/* node in sched list */

typedef struct schedcmd  *Schedcmd;

struct schedcmd {

    struct schedcmd *next;

    char *cmd;			/* command to run */

    time_t time;		/* when to run it */

};

/* the list of sched jobs pending */

static struct schedcmd *schedcmds;

/**/

static int

bin_sched(UNUSED(char *nam), char **argv, UNUSED(Options ops), UNUSED(int func))

{

    char *s = *argv++;

    time_t t;

    long h, m;

    struct tm *tm;

    struct schedcmd *sch, *sch2, *schl;

    int sn;

    /* If the argument begins with a -, remove the specified item from the

    schedule. */

    if (s && *s == '-') {

	sn = atoi(s + 1);

	if (!sn) {

	    zwarnnam("sched", "usage for delete: sched -<item#>.", NULL, 0);

	    return 1;

	}

	for (schl = (struct schedcmd *)&schedcmds, sch = schedcmds, sn--;

	     sch && sn; sch = (schl = sch)->next, sn--);

	if (!sch) {

	    zwarnnam("sched", "not that many entries", NULL, 0);

	    return 1;

	}

	schl->next = sch->next;

	zsfree(sch->cmd);

	zfree(sch, sizeof(struct schedcmd));

	return 0;

    }

    /* given no arguments, display the schedule list */

    if (!s) {

	char tbuf[40];

	for (sn = 1, sch = schedcmds; sch; sch = sch->next, sn++) {

	    t = sch->time;

	    tm = localtime(&t);

	    ztrftime(tbuf, 20, "%a %b %e %k:%M:%S", tm);

	    printf("%3d %s %s\n", sn, tbuf, sch->cmd);

	}

	return 0;

    } else if (!*argv) {

	/* other than the two cases above, sched *

	 *requires at least two arguments        */

	zwarnnam("sched", "not enough arguments", NULL, 0);

	return 1;

    }

    /* The first argument specifies the time to schedule the command for.  The

    remaining arguments form the command. */

    if (*s == '+') {

	/* + introduces a relative time.  The rest of the argument is an

	hour:minute offset from the current time.  Once the hour and minute

	numbers have been extracted, and the format verified, the resulting

	offset is simply added to the current time. */

	h = zstrtol(s + 1, &s, 10);

	if (*s != ':') {

	    zwarnnam("sched", "bad time specifier", NULL, 0);

	    return 1;

	}

	m = zstrtol(s + 1, &s, 10);

	if (*s) {

	    zwarnnam("sched", "bad time specifier", NULL, 0);

	    return 1;

	}

	t = time(NULL) + h * 3600 + m * 60;

    } else {

	/* If there is no +, an absolute time of day must have been given.

	This is in hour:minute format, optionally followed by a string starting

	with `a' or `p' (for a.m. or p.m.).  Characters after the `a' or `p'

	are ignored. */

	h = zstrtol(s, &s, 10);

	if (*s != ':') {

	    zwarnnam("sched", "bad time specifier", NULL, 0);

	    return 1;

	}

	m = zstrtol(s + 1, &s, 10);

	if (*s && *s != 'a' && *s != 'A' && *s != 'p' && *s != 'P') {

	    zwarnnam("sched", "bad time specifier", NULL, 0);

	    return 1;

	}

	t = time(NULL);

	tm = localtime(&t);

	t -= tm->tm_sec + tm->tm_min * 60 + tm->tm_hour * 3600;

	if (*s == 'p' || *s == 'P')

	    h += 12;

	t += h * 3600 + m * 60;

	/* If the specified time is before the current time, it must refer to

	tomorrow. */

	if (t < time(NULL))

	    t += 3600 * 24;

    }

    /* The time has been calculated; now add the new entry to the linked list

    of scheduled commands. */

    sch = (struct schedcmd *) zshcalloc(sizeof *sch);

    sch->time = t;

    sch->cmd = zjoin(argv, ' ', 0);

    sch->next = NULL;

    for (sch2 = (struct schedcmd *)&schedcmds; sch2->next; sch2 = sch2->next);

    sch2->next = sch;

    return 0;

}

/* Check scheduled commands; call this function from time to time. */

/**/

static void

checksched(void)

{

    time_t t;

    struct schedcmd *sch, *schl;

    if(!schedcmds)

	return;

    t = time(NULL);

    for (schl = (struct schedcmd *)&schedcmds, sch = schedcmds; sch;

	 sch = (schl = sch)->next) {

	if (sch->time <= t) {

	    execstring(sch->cmd, 0, 0);

	    schl->next = sch->next;

	    zsfree(sch->cmd);

	    zfree(sch, sizeof(struct schedcmd));

	    sch = schl;

	}

    }

}

static void (*p_checksched) _((void)) = checksched;

static struct linknode n_checksched = { NULL, NULL, &p_checksched };

static struct builtin bintab[] = {

    BUILTIN("sched", 0, bin_sched, 0, -1, 0, NULL, NULL),

};

/**/

int

setup_(UNUSED(Module m))

{

    return 0;

}

/**/

int

boot_(Module m)

{

    if(!addbuiltins(m->nam, bintab, sizeof(bintab)/sizeof(*bintab)))

	return 1;

    uaddlinknode(prepromptfns, &n_checksched);

    return 0;

}

/**/

int

cleanup_(Module m)

{

    struct schedcmd *sch, *schn;

    for (sch = schedcmds; sch; sch = schn) {

	schn = sch->next;

	zsfree(sch->cmd);

	zfree(sch, sizeof(*sch));

    }

    uremnode(prepromptfns, &n_checksched);

    deletebuiltins(m->nam, bintab, sizeof(bintab)/sizeof(*bintab));

    return 0;

}

/**/

int

finish_(UNUSED(Module m))

{

    return 0;

}