source: trunk/athena/bin/xdsc/cache.c @ 14093

/*
Copyright 1991 by the Massachusetts Institute of Technology

Permission to use, copy, modify, and distribute this
software and its documentation for any purpose and without
fee is hereby granted, provided that the above copyright
notice appear in all copies and that both that copyright
notice and this permission notice appear in supporting
documentation, and that the name of M.I.T. not be used in
advertising or publicity pertaining to distribution of the
software without specific, written prior permission.
M.I.T. makes no representations about the suitability of
this software for any purpose.  It is provided "as is"
without express or implied warranty.
*/

/*
**  cache.c:  manage the files in /tmp
**
**  Ensure we have the ones we need, and get rid of the ones no
/*
**  cache.c:  manage the files in /tmp
**
**  Ensure we have the ones we need, and get rid of the ones no
**  longer in use.
**
*/

#include        <stdio.h>
#include        <X11/Intrinsic.h>
#include        <X11/StringDefs.h>
#include        <X11/IntrinsicP.h>
#include        <X11/CoreP.h>
#include        <X11/Xaw/Command.h>
#include        <X11/Xaw/AsciiText.h>
#include        <X11/Xaw/TextP.h>
#include        <fcntl.h>
#include        "xdsc.h"

#define         NUM_CACHED_FILES        5
#define         CACHE_DIR_NEXT          1
#define         CACHE_DIR_PREV          2
#define         CACHE_DIR_NREF          3
#define         CACHE_DIR_PREF          4


static char rcsid[] = "$Id: cache.c,v 1.13 1999-12-16 01:58:23 danw Exp $";

extern char     *RunCommand();
extern EntryRec         toplevelbuttons[2][MAX_BUTTONS];
extern TextWidget       bottextW, toptextW;
extern Boolean  debug;
extern char     filebase[];
extern int      topscreen;
extern int      edscversion;
extern Widget   topW;
extern void     TopSelect();
extern Boolean  nocache;
extern char     axis[];

int     next=0, prev=0;
static int      nref = 0, pref=0, fref=0, lref=0;
static int      first=0, last=0;
static int      highestseen;
static int      current;

static int      cache[NUM_CACHED_FILES] = {-1,-1,-1,-1,-1};
static char     currentmtglong[LONGNAMELEN] = "";
static char     currentmtgshort[SHORTNAMELEN] = "";

char    *GetTransactionFile();

char *
CurrentMtg(which)
int     which;
{
        if (which == 0)
                return (currentmtglong);
        else
                return (currentmtgshort);
}

int
SaveMeetingNames(newlong, newshort)
char    *newlong;
char    *newshort;
{
        char    oldlong[LONGNAMELEN];
        char    oldshort[SHORTNAMELEN];
        if (*currentmtglong) {
                MarkLastRead();
                DeleteOldTransactions();
        }

        if (*newlong) {
                strcpy (oldlong, currentmtglong);
                strcpy (currentmtglong, newlong);
                strcpy (oldshort, currentmtgshort);
                strcpy (currentmtgshort, newshort);
                if (SetUpTransactionNumbers() == -1) {
                        strcpy (currentmtglong, oldlong);
                        strcpy (currentmtgshort, oldshort);
                        return (-1);
                }
        }

        else {
                *currentmtglong = '\0';
                *currentmtgshort = '\0';
        }
        return (0);
}

/*
**  GoToTransaction updates the data structures and cache so that
**  we are in a particular transaction.
**
**  if 'update' is True (it usually is) we put the contents of the
**  transaction into the lower text widget.
*/

GoToTransaction (num, update)
int     num;
Boolean update;
{
        static char     command[LONGNAMELEN + 25];
        char            *filename;
        char            *returndata;
        int             transactionnum;

        if (!num) return;

        if (num < 0)
                transactionnum = TransactionNum(num);
        else
                transactionnum = num;

        if (update && topscreen == LISTTRNS);
                UpdateHighlightedTransaction(transactionnum);

        sprintf (command, "Reading %s [%d-%d], #%d...", 
                                currentmtglong, first, last, transactionnum);
        PutUpStatusMessage(command);

        if ((filename = GetTransactionFile(num)) == (char *) -1)
                return (-1);

        if (update)
                FileIntoWidget(filename, bottextW);

        sprintf (command, "(gti %d %s)\n", transactionnum, currentmtglong);
        returndata = RunCommand (command, NULL, NULL, True);

        if ((int) returndata <= 0) goto DONE;

        sscanf (        returndata, 
                        "%*c%d%d%d%d%d%d%d%*s",
                        &current, &prev, &next, &pref, 
                        &nref, &fref, &lref);

        myfree(returndata);
        CheckButtonSensitivity(BUTTONS_UPDATE);

        if (!nocache)
                CacheSurroundingTransactions();

        if ( current >  highestseen)
                highestseen = current;

        if ( next > last || current > last) {
                MarkLastRead();
                (void) SetUpTransactionNumbers();
        }

        if (highestseen == last && topscreen == MAIN)
                RemoveLetterC();
DONE:
        sprintf (command, "Reading %s [%d-%d], #%d", 
                                currentmtglong, first, last, transactionnum);
        PutUpStatusMessage(command);
}

DeleteOldTransactions()
{
        char            filename[80];
        unsigned int    fd;

        DeleteTransactionFile(current);
        DeleteTransactionFile(prev);
        DeleteTransactionFile(next);
        DeleteTransactionFile(pref);
        DeleteTransactionFile(nref);

        sprintf (filename, "%s-list", filebase);
        if ((fd = open(filename, O_RDONLY)) != -1) {
                close (fd);
                unlink (filename);
        }

        next=0, prev=0, nref=0;
        pref=0, fref=0, lref=0;
        first=0, last=0, current=0;
}

/*
** Read in the transactions immedidately before and after the
** current one.
*/

CacheSurroundingTransactions()
{

        int             i;

/*
** Remove unnecessary files
*/

        for (i = 0; i < NUM_CACHED_FILES; i++) {
                if (    cache[i] != next && cache[i] != prev &&
                        cache[i] != nref && cache[i] != pref &&
                        cache[i] != current && cache[i] != -1) {

                        DeleteTransactionFile(cache[i]);
                }
        }

/*
** Get the files we need
*/
        (void) GetTransactionFile (next);
        (void) GetTransactionFile (prev);
        (void) GetTransactionFile (nref);
        (void) GetTransactionFile (pref);
        (void) GetTransactionFile (current);

}

/*
** Remove the file from /tmp and the cache.
*/

DeleteTransactionFile(num)
int     num;
{
        char    filename[50];
        int     i;

        sprintf (filename, "%s-%d", filebase, num);
        unlink (filename);

        for (i = 0; i < NUM_CACHED_FILES; i++)
                if (cache[i] == num)
                        cache[i] = -1;
}

/*
**  This function behaves differently depending on the version of
**  edsc we're talking to.  
**
**  If edsc is doing the caching, just ask for the transaction and
**  return the filename.
**
**  If we're doing the caching, ask if the file is already in the cache,
**  and return the filename if it is.  Otherwise, run the 
**  edsc command to fetch it, note it as cached, and return the filename.
**
*/

char *
GetTransactionFile(num)
int     num;
{
        static char     filename[50];
        char            command[LONGNAMELEN + 25];
        int             i;
        char            *retval;
        int             transactionnum;
        int             direction;

        if (num == 0)
                return((char *)-1);

/*
** have we been passed a symbol instead of a number?
*/

        if (num < 0)
                transactionnum = TransactionNum(num);
        else
                transactionnum = num;

        if (!nocache)
                sprintf (filename, "%s-%d", filebase, transactionnum);
/*
** See if the file is in our cache.  If so, return its filename;.
*/
        if (!nocache) {
                for (i = 0; i < NUM_CACHED_FILES; i++) {
                        if (cache[i] == num) {
                                return (filename);
                        }
                }
        }

/*
** If file doesn't exist, go get it.
*/
        if (nocache) {
                switch (num) {
                case NEXT:      
                        direction = CACHE_DIR_NEXT;
                        break;
                case PREV:      
                        direction = CACHE_DIR_PREV;
                        break;
                case NREF:      
                        direction = CACHE_DIR_NREF;
                        break;
                case PREF:      
                        direction = CACHE_DIR_PREF;
                        break;
                default:
                        direction = 0;
                        break;
                }

                sprintf (       command, "(gtfc %d %d %s)\n", 
                                direction, transactionnum, currentmtglong);

                retval = RunCommand (command, NULL, NULL, True);
                if ((int) retval <= 0) 
                        return((char *)-1);
                sscanf (retval, "(\"%[^\"]", filename);
        }

        else {
                sprintf (       command, "(gtf %s %d %s)\n", 
                                filename, transactionnum, currentmtglong);
                retval = RunCommand (command, NULL, NULL, True);
                if ((int) retval <= 0) 
                        return((char *)-1);

                for (i = 0; i < NUM_CACHED_FILES; i++) {
                        if (cache[i] == -1) {
                                cache[i] = num;
                                break;
                        }
                }
        }

        myfree (retval);
        return (filename);
}

/*
** Return the highestseen from mtg.  Also set first, last, and highestseen.
** Set current to highestseen if it's not already set (ie, we've just
** entered the meeting)
**
** Return -1 if something went wrong.
*/

int
SetUpTransactionNumbers()
{

        char    command[LONGNAMELEN + 25];
        char    *retval;
        static int      oldhighestseen = 0;

        sprintf (command, "(gmi %s)\n", currentmtglong);

        retval = RunCommand (command, NULL, NULL, True);
        if ((int) retval <= 0) return (-1);

        sscanf (retval, "(\"%*[^\"]\" \"%*[^\"]\" \"%*[^\"]\" %d %d %*d %*d \"%*[^\"]\" \"%*[^\"]\" %*d \"%[^\"]\" %d",
                &first, &last, axis, &highestseen);

        oldhighestseen = highestseen;
                        
        if (last == 0 && first == 0) {
                fprintf (stderr,"xdsc:  Reply out of sync with request!\n");
                fprintf (stderr,"xdsc:  requested '%s', got '%s'\n",command, retval);
                PutUpWarning(   "INTERNAL ERROR DETECTED", 
                                "I suggest you quit immediately to avoid\npossible corruption of your .meetings file.", True);
                myfree(retval);
                return (-1);
        }
        myfree(retval);

        if (highestseen > last) {
                PutUpWarning(   "WARNING",
                                "The highest-read transaction in this\nmeeting no longer exists.\nGoing to end of the meeting.", True);
                highestseen = last;
        }

        if (debug) {
                fprintf (stderr, "highestseen message of %s is %d\n",
                                currentmtglong, highestseen);

                fprintf (stderr, "first is %d, last is %d\n",first, last);
        }

        GoToTransaction (highestseen, False);

        return (highestseen);
}

MarkLastRead()
{
        static char     command[LONGNAMELEN + 25];

        if (*currentmtglong)  {
                sprintf (       command, 
                                "(ss %d %s)\n", 
                                highestseen,
                                currentmtglong);
                if (edscversion >= 24)
                        (void) RunCommand (command, NULL, NULL, True);
                else
                        (void) RunCommand (command, NULL, NULL, False);
        }

}

TransactionNum(arg)
int     arg;
{
        switch (arg) {
                case NEXT:
                        return(next);
                case PREV:
                        return(prev);
                case NREF:
                        return(nref);
                case PREF:
                        return(pref);
                case LREF:
                        return(lref);
                case FREF:
                        return(fref);
                case FIRST:
                        return(first);
                case LAST:
                        return(last);
                case CURRENT:
                        return(current);
                case HIGHESTSEEN:
                        return(highestseen);
                default:
                        fprintf (stderr, "Unknown arg to TransactionNum: %d\n", arg);
                        return(0);
        }
}

MoveToMeeting(which)
int     which;
{
        Arg     args[2];
        Boolean transactionflag = False;
/*
** If we're currently showing transactions, we have to restore the top-level
** list of meetings.
*/
        if (topscreen == LISTTRNS) {
                XawTextDisableRedisplay(toptextW);
                TopSelect (NULL, 4 + (1 << 4));
                transactionflag = True;
        }

/*
** HighlightNewItem will eventually call SaveMeetingNames and 
** SetUpTransactionNumbers to get the next, prev, etc. vars set.
*/
        if (HighlightNewItem(toptextW, which, True) == 0) {

/*
** Need to restore transaction list?
*/
                if (transactionflag == True) {
                        TopSelect (NULL, 4 + (0 << 4));
                        XawTextEnableRedisplay(toptextW);
                }

/*
** Clear out bottom text window.
*/
                XtSetArg (args[0], XtNstring, "");
                XtSetArg (args[1], XtNlength, 0);
                XtSetValues (bottextW, args, 1);

/*
** If we're at the end of the meeting, make it so the "next" button
** will show us the last transaction.
*/
                if (next == 0)
                        next = last;

                CheckButtonSensitivity(BUTTONS_ON);
                return (0);
        }

        else {
                return (-1);
        }
}

/*
** Make sure bottom buttons are set appropriately, according to context
** and mode.
**
** Mode = BUTTONS_UPDATE: turn on appropriate buttons, if sensitive = True.
** Mode = BUTTONS_OFF:  Turn off all buttons.  Set sensitive = False.
** Mode = BUTTONS_ON:  Turn on appropriate buttons.  Set sensitive = True.
**
*/
CheckButtonSensitivity(mode)
int mode;
{
        static Boolean  sensitive = True;
        Arg             args[2];

        if (mode == BUTTONS_ON) sensitive = True;
        if (mode == BUTTONS_OFF) sensitive = False;

        if (next && sensitive) {
                XtSetArg(args[0], XtNsensitive, True);
                XtSetArg(args[1], XtNborderWidth, 1);
        }
        else {
                XtSetArg(args[0], XtNsensitive, False);
                XtSetArg(args[1], XtNborderWidth, 4);
        }
        XtSetValues ((toplevelbuttons[1][0]).button, args, 2);

        if (prev && sensitive)
                XtSetArg(args[0], XtNsensitive, True);
        else
                XtSetArg(args[0], XtNsensitive, False);
        XtSetValues ((toplevelbuttons[1][1]).button, args, 1);

        if (nref && sensitive)
                XtSetArg(args[0], XtNsensitive, True);
        else
                XtSetArg(args[0], XtNsensitive, False);
        XtSetValues ((toplevelbuttons[1][2]).button, args, 1);

        if (pref && sensitive)
                XtSetArg(args[0], XtNsensitive, True);
        else
                XtSetArg(args[0], XtNsensitive, False);
        XtSetValues ((toplevelbuttons[1][3]).button, args, 1);

        if (topscreen == LISTTRNS && sensitive)
                XtSetArg(args[0], XtNsensitive, True);
        else
                XtSetArg(args[0], XtNsensitive, False);
        XtSetValues ((toplevelbuttons[0][5]).button, args, 1);

        if (axis[0] == ' ' && axis[6] == ' ')
                XtSetArg(args[0], XtNsensitive, False);
        else
                XtSetArg(args[0], XtNsensitive, True);
        XtSetValues ((toplevelbuttons[1][5]).button, args, 1);

        if (axis[0] == ' ')
                XtSetArg(args[0], XtNsensitive, False);
        else
                XtSetArg(args[0], XtNsensitive, True);
        XtSetValues ((toplevelbuttons[1][5]).nextrec->button, args, 1);

        if (axis[6] == ' ')
                XtSetArg(args[0], XtNsensitive, False);
        else
                XtSetArg(args[0], XtNsensitive, True);
        XtSetValues ((toplevelbuttons[1][5]).nextrec->nextrec->button, args, 1);

        XtSetArg(args[0], XtNsensitive, False);
        XtSetValues ((toplevelbuttons[1][6]).nextrec->nextrec->button, args, 1);
}