/*
 * Copyright 2000, International Business Machines Corporation and others.
 * All Rights Reserved.
 * 
 * This software has been released under the terms of the IBM Public
 * License.  For details, see the LICENSE file in the top-level source
 * directory or online at http://www.openafs.org/dl/license10.html
 */

#include <afs/param.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <lwp.h>
#include <time.h>
#include <ctype.h>
#include <stdio.h>
#ifdef AFS_NT40_ENV
#include <io.h>
#endif
#include <afs/ktime.h>
#include <afs/afsutil.h>
#include <afs/procmgmt.h>  /* signal(), kill(), wait(), etc. */
#include "bnode.h"

static int cron_timeout(), cron_getstat(), cron_setstat(), cron_delete();
static int cron_procexit(), cron_getstring(), cron_getparm(), cron_restartp();
static int cron_hascore();
struct bnode *cron_create();
extern char *ktime_DateOf();

#define	SDTIME		60	    /* time in seconds given to a process to evaporate */

struct bnode_ops cronbnode_ops = {
    cron_create,
    cron_timeout,
    cron_getstat,
    cron_setstat,
    cron_delete,
    cron_procexit,
    cron_getstring,
    cron_getparm,
    cron_restartp,
    cron_hascore,
};
    
struct cronbnode {
    struct bnode b;
    afs_int32 zapTime;		/* time we sent a sigterm */
    char *command;
    char *whenString;		/* string rep. of when to run */
    struct bnode_proc *proc;
    afs_int32 lastStart;		/* time last started process */
    afs_int32 nextRun;		/* next time to run, if no proc running */
    struct ktime whenToRun;	/* high-level rep of when should we run this guy */
    afs_int32 when;			/* computed at creation time and procexit time */
    char everRun;		/* true if ever ran */
    char waitingForShutdown;	/* have we started any shutdown procedure? */
    char running;   /* is process running? */
    char killSent;  /* have we tried sigkill signal? */
};

static int cron_hascore(abnode)
register struct ezbnode *abnode; {
    char tbuffer[256];

    bnode_CoreName(abnode, (char *) 0, tbuffer);
    if (access(tbuffer, 0) == 0) return 1;
    else return 0;
}

/* run at creation or after process exit.  figures out if we're all done (if a
    one shot run) or when we should run again.  Sleeps until we should run again.
    Note that the computation of when we should run again is made in procexit
    and/or create procs.  This guy only schedules the sleep */
ScheduleCronBnode(abnode)
register struct cronbnode *abnode; {
    register afs_int32 code;
    register afs_int32 temp;
    struct bnode_proc *tp;

    /* If this proc is shutdown, tell bproc() to no longer run this job */
    if (abnode->b.goal == BSTAT_SHUTDOWN) {
        bnode_SetTimeout(abnode, 0);
	return 0;
    }

    /* otherwise we're supposed to be running, figure out when */
    if (abnode->when == 0) {
	/* one shot */
	if (abnode->everRun) {
	    /* once is enough */
	    bnode_Delete(abnode);
	    return 0;
	}
	/* otherwise start it */
	if (!abnode->running) {
	    /* start up */
	    abnode->lastStart = FT_ApproxTime();
	    code = bnode_NewProc(abnode, abnode->command, (char *) 0, &tp);
	    if (code) {
		bozo_Log("cron bnode %s failed to start (code %d)\n",
			 abnode->b.name, code);
		return code;
	    }
	    abnode->everRun = 1;
	    abnode->running = 1;
	    abnode->proc = tp;
	    return 0;
	}
    }
    else {
	/* run periodically */
	if (abnode->running) return 0;
	/* otherwise find out when to run it, and do it then */
	temp = abnode->when - FT_ApproxTime();
	if (temp < 1) temp = 1;	/* temp is when to start dude */
	bnode_SetTimeout(abnode, temp);
    }
}

static int cron_restartp (abnode)
register struct cronbnode *abnode; {
    return 0;
}

static int cron_delete(abnode)
struct cronbnode *abnode; {
    free(abnode->command);
    free(abnode->whenString);
    free(abnode);
    return 0;
}

struct bnode *cron_create(ainstance, acommand, awhen)
char *ainstance;
char *awhen;
char *acommand; {
    struct cronbnode *te;
    afs_int32 code;
    char *cmdpath;
    extern char *copystr();

    /* construct local path from canonical (wire-format) path */
    if (ConstructLocalBinPath(acommand, &cmdpath)) {
	bozo_Log("BNODE: command path invalid '%s'\n", acommand);
	return (struct bnode *)0;
    }

    te = (struct cronbnode *) malloc(sizeof(struct cronbnode));
    bzero(te, sizeof(struct cronbnode));
    code = ktime_ParsePeriodic(awhen, &te->whenToRun);
    if (code < 0) {
	free(te);
	free(cmdpath);
	return (struct bnode *) 0;
    }
    bnode_InitBnode(te, &cronbnode_ops, ainstance);
    te->when = ktime_next(&te->whenToRun, 0);
    te->command = cmdpath;
    te->whenString = copystr(awhen);
    return (struct bnode *) te;
}

/* called to SIGKILL a process if it doesn't terminate normally.  In cron, also
    start up a process if it is time and not already running */
static int cron_timeout(abnode)
struct cronbnode *abnode; {
    register afs_int32 temp;
    register afs_int32 code;
    struct bnode_proc *tp;

    if (!abnode->running) {
	if (abnode->when == 0) return 0;    /* spurious timeout activation */
	/* not running, perhaps we should start it */
	if (FT_ApproxTime() >= abnode->when) {
	    abnode->lastStart = FT_ApproxTime();
	    bnode_SetTimeout(abnode, 0);
	    code = bnode_NewProc(abnode, abnode->command, (char *) 0, &tp);
	    if (code) {
		bozo_Log("cron failed to start bnode %s (code %d)\n",
			 abnode->b.name, code);
		return code;
	    }
	    abnode->everRun = 1;
	    abnode->running = 1;
	    abnode->proc = tp;
	}
	else {
	    /* woke up too early, try again */
	    temp = abnode->when - FT_ApproxTime();
	    if (temp < 1) temp = 1;
	    bnode_SetTimeout(abnode, temp);
	}
    }
    else {
	if (!abnode->waitingForShutdown) return 0;	/* spurious */
	/* send kill and turn off timer */
	bnode_StopProc(abnode->proc, SIGKILL);
	abnode->killSent = 1;
	bnode_SetTimeout(abnode, 0);
    }
    return 0;
}

static int cron_getstat(abnode, astatus)
struct cronbnode *abnode;
afs_int32 *astatus; {
    register afs_int32 temp;
    if (abnode->waitingForShutdown) temp = BSTAT_SHUTTINGDOWN;
    else if (abnode->b.goal == 0) temp = BSTAT_SHUTDOWN;
    else if (abnode->everRun && abnode->when == 0 && !abnode->running) {
	/* special hack: bnode deletion won't happen if bnode is active, so
	   we make bnodes that are ready to be deleted automatically appear
	   as BSTAT_SHUTDOWN so bnode_Delete is happy. */
	temp = BSTAT_SHUTDOWN;
    }
    else temp = BSTAT_NORMAL;
    *astatus = temp;
    return 0;
}

static int cron_setstat(abnode, astatus)
register struct cronbnode *abnode;
afs_int32 astatus; {

    if (abnode->waitingForShutdown) return BZBUSY;
    if (astatus == BSTAT_SHUTDOWN) {
       if (abnode->running) {
	  /* start shutdown */
	  bnode_StopProc(abnode->proc, SIGTERM);
	  abnode->waitingForShutdown = 1;
	  bnode_SetTimeout(abnode, SDTIME);
	  /* When shutdown is complete, bproc() calls BOP_PROCEXIT()
	   * [cron_procexit()] which will tell bproc() to no longer
	   * run this cron job.
	   */
       } else {
	  /* Tell bproc() to no longer run this cron job */
	  bnode_SetTimeout(abnode, 0);
       }
    }
    else if (astatus == BSTAT_NORMAL) {
        /* start the cron job
	 * Figure out when to run next and schedule it
	 */
        abnode->when = ktime_next(&abnode->whenToRun, 0);
	ScheduleCronBnode(abnode);
    }
    return 0;
}

static int cron_procexit(abnode, aproc)
struct cronbnode *abnode;
struct bnode_proc *aproc; {
    /* process has exited */

    /* log interesting errors for folks */
    if (aproc->lastSignal)
	bozo_Log("cron job %s exited due to signal %d\n",
		 abnode->b.name, aproc->lastSignal);
    else if (aproc->lastExit)
	bozo_Log("cron job %s exited with non-zero code %d\n",
		 abnode->b.name, aproc->lastExit);

    abnode->waitingForShutdown = 0;
    abnode->running = 0;
    abnode->killSent = 0;
    abnode->proc = (struct bnode_proc *) 0;

    /* Figure out when to run next and schedule it */
    abnode->when = ktime_next(&abnode->whenToRun, 0);
    ScheduleCronBnode(abnode);
    return 0;
}

static int cron_getstring(abnode, abuffer, alen)
struct cronbnode *abnode;
char *abuffer;
afs_int32 alen;{
    if (abnode->running) strcpy(abuffer, "running now");
    else if (abnode->when==0) strcpy(abuffer, "waiting to run once");
    else sprintf(abuffer, "run next at %s", ktime_DateOf(abnode->when));
    return 0;
}

static cron_getparm(abnode, aindex, abuffer, alen)
struct cronbnode *abnode;
afs_int32 aindex;
char *abuffer;
afs_int32 alen; {
    if (aindex == 0) strcpy(abuffer, abnode->command);
    else if (aindex == 1) {
	strcpy(abuffer, abnode->whenString);
    }
    else return BZDOM;
    return 0;
}
