/* tfslog.c:
 *
 * 	Optional facility for TFS that supports the ability to log all
 *	tfs actions that affect flash, to a log file.
 *
 *	This function is called by tfsadd(), tfsunlink() and tfsipmod() to
 *	write to a log file indicating that something in tfs has been changed.
 *	Note that the function can be called at any user level, but it must be
 *	able to modify the TFS_CHANGELOG_FILE that has "u3" flags.  The 
 *	user level must be temporarily forced to MAXUSRLEVEL for this.
 *
 *	General notice:
 *	This code is part of a boot-monitor package developed as a generic base
 *	platform for embedded system designs.  As such, it is likely to be
 *	distributed to various projects beyond the control of the original
 *	author.  Please notify the author of any enhancements made or bugs found
 *	so that all may benefit from the changes.  In addition, notification back
 *	to the author will allow the new user to pick up changes that may have
 *	been made by other users after this version of the code was distributed.
 *
 *	Author:	Ed Sutter
 *	email:	esutter@lucent.com		(home: lesutter@worldnet.att.net)
 *	phone:	908-582-2351			(home: 908-889-5161)
 */
#include "config.h"
#include "stddefs.h"
#include "genlib.h"
#include "tfs.h"

#if TFS_CHANGELOG_SIZE
static int	tfsLogging;
#endif

void
tfslog(int action, char *string)
{
#if TFS_CHANGELOG_SIZE
	static char *tfslogaction[] = { "ADD", "DEL", "IPM", " ON", "OFF" };
	
	extern	void *setTmpMaxUsrLvl();
	static	char buf[TFS_CHANGELOG_SIZE];
	TFILE	*tfp;
	int		(*fptr)();
	char	*eol, *eob, *logaction, tbuf[32];
	int		newfsize, fsize, lsize, tfd, err, len, tbuflen;

	switch(action) {
		case TFSLOG_ADD:		/* Return here if logging is off,	*/
		case TFSLOG_DEL:		/* or this tfslog() call is on the 	*/
		case TFSLOG_IPM:		/* TFS_CHANGELOG_FILE itself.		*/
			if (!tfsLogging || !strcmp(string,TFS_CHANGELOG_FILE))
				return;
			break;
		case TFSLOG_ON:
			if (tfsLogging == 1)
				return;
			tfsLogging = 1;
			break;
		case TFSLOG_OFF:
			if (tfsLogging == 0)
				return;
			tfsLogging = 0;
			break;
	}

	/* Force the getUsrLvl() function to return MAX: */
	fptr = (int(*)())setTmpMaxUsrLvl();

	logaction = tfslogaction[action];
	tfp = tfsstat(TFS_CHANGELOG_FILE);
	tfsGetAtime(0,tbuf,sizeof(tbuf));
	tbuflen = strlen(tbuf); 

	if (tfp) {
		tfd = tfsopen(TFS_CHANGELOG_FILE,TFS_RDONLY,0);
		fsize = tfsread(tfd,buf,TFS_CHANGELOG_SIZE);
		tfsclose(tfd,0);

		newfsize = (fsize+strlen(logaction)+strlen(string)+3);
		if (tbuflen)
			newfsize += tbuflen + 3;

		eob = buf + fsize;

		/* If newfsize is greater than the maximum size the file is
		 * allowed to grow, then keep removing the first line
		 * (oldest entry) until new size is within the limit...
		 */
		if (newfsize > TFS_CHANGELOG_SIZE) {
			lsize = 0;
			eol = buf;
			while ((newfsize-lsize) > TFS_CHANGELOG_SIZE) {
				while((*eol != '\r') && (*eol != '\n')) eol++;
				while((*eol == '\r') || (*eol == '\n')) eol++;
				lsize = eol-buf;
			}
			fsize -= lsize;
			newfsize -= lsize;
			eob -= lsize;
			memcpy(buf,eol,fsize);
		}
		if (tbuflen)
			sprintf(eob,"%s: %s @ %s\n",logaction,string,tbuf);
		else
			sprintf(eob,"%s: %s\n",logaction,string);
		err = _tfsunlink(TFS_CHANGELOG_FILE);
		if (err < 0)
			printf("%s: %s\n",TFS_CHANGELOG_FILE,
				(char *)tfsctrl(TFS_ERRMSG,err,0));
		err = tfsadd(TFS_CHANGELOG_FILE,0,"u3",buf,newfsize);
		if (err < 0)
			printf("%s: %s\n",TFS_CHANGELOG_FILE,
				(char *)tfsctrl(TFS_ERRMSG,err,0));
	}
	else {
		if (tbuflen)
			len = sprintf(buf,"%s: %s @ %s\n",logaction,string,tbuf);
		else
			len = sprintf(buf,"%s: %s\n",logaction,string);
		err = tfsadd(TFS_CHANGELOG_FILE,0,"u3",buf,len);
		if (err < 0)
			printf("%s: %s\n",TFS_CHANGELOG_FILE,
				(char *)tfsctrl(TFS_ERRMSG,err,0));
	}

	/* Restore the original getUsrLvl() functionality: */
	clrTmpMaxUsrLvl(fptr);
#endif
}

int
tfsLogCmd(int argc,char *argv[], int optind)
{
#if TFS_CHANGELOG_SIZE
	int	status;
	int	retval = 0;

	if (getUsrLvl() < MAXUSRLEVEL) {
		status = showTfsError(TFSERR_USERDENIED,0);
	}
	else {
		if (argc == optind + 3) {
			if (!strcmp(argv[optind+1],"on"))
				tfslog(TFSLOG_ON,argv[optind+2]);
			else if (!strcmp(argv[optind+1],"off"))
				tfslog(TFSLOG_OFF,argv[optind+2]);
			else
				retval = -1;
		}
		else if (argc == optind + 1)
			printf("TFS logging %sabled\n",tfsLogging ? "en" : "dis");
		else
			retval = -1;
	}
	return(retval);
#else
	return(-1);
#endif
}