#include	<u.h>#include	<libc.h>#include	<ctype.h> #define	MINUTE(x)	((long)(x)*60L)#define	HOUR(x)		(MINUTE(x)*60L)#define	YEAR(x)		(HOUR(x)*24L*360L) int	verb;int	uflag;int	force;int	diff;int	diffb;char*	sflag;char *sys; void	ysearch(char*);long	starttime(char*);void	lastbefore(ulong, char*, char*, char*);char*	prtime(ulong); intmain(int argc, char *argv[]){	int i;		sys = sysname();	if(strncmp(sys, "amsterdam", 9) == 0)	/* BUG */		sys = "am"; 	ARGBEGIN {	default:		goto usage;	case 'v':		verb = 1;		break;	case 'f':		force = 1;		break;	case 'd':		diff = 1;		break;	case 'b':		diffb = 1;		break;	case 's':		sflag = ARGF();		break;	case 'u':		uflag = 1;		break;	} ARGEND 	if(argc == 0) {	usage:		fprint(2, "usage: hist [-bdfuv] [-s yyyymmdd] files\n");		exits(0);	} 	for(i=0; i<argc; i++)		ysearch(argv[i]);	exits(0);	return 0;} intstrprefix(char *a, char *aa){	return memcmp(a, aa, strlen(a)) == 0;} voidysearch(char *file){	char *ndump;	char fil[400], buf[500], nbuf[100], pair[2][500];	Tm *tm;	Dir *dir, *d;	ulong otime, dt;	int toggle, started, missing; 	started = 0;	dir = dirstat(file);	if(dir == nil)		fprint(2, "history: warning: %s does not exist\n", file);	else{		print("%s %s %lld\n", prtime(dir->mtime), file, dir->length);		started = 1;		strcpy(pair[1], file);	}	free(dir);	fil[0] = 0;	if(file[0] != '/') {		getwd(strchr(fil, 0), 100);		strcat(fil, "/");	}	strcat(fil, file);	cleanname(fil); 	sprint(nbuf, "/dump/%s", sys);	ndump = nbuf; 	tm = localtime(time(0));	sprint(buf, "%s/%.4d/", ndump, tm->year+1900);	if(access(buf, AREAD) < 0){		print("cannot access %s\n", buf);		return;	} 	otime = starttime(sflag);	toggle = 0;	for(;;) {		lastbefore(otime, fil, buf, ndump);		dir = dirstat(buf);		if(dir == nil) {			if(!force)				return;			dir = malloc(sizeof(Dir));			nulldir(dir);			dir->mtime = otime + 1;		}		dt = HOUR(12);		missing = 0;		while(otime <= dir->mtime){			if(verb)				print("backup %ld, %ld\n", dir->mtime, otime-dt);			lastbefore(otime-dt, fil, buf, ndump);			d = dirstat(buf);			if(d == nil){				if(!force)					return;				if(!missing)					print("removed %s\n", buf);				missing = 1;			}else{				free(dir);				dir = d;			}			dt += HOUR(12);		}		strcpy(pair[toggle], buf);		if(diff && started){			if(verb)				print("diff %s %s\n", pair[toggle^1], pair[toggle]);			switch(rfork(RFFDG|RFPROC)){			case 0:				execlp("diff", "diff", diffb ? "-cb" : "-c", pair[toggle], pair[toggle ^ 1], (char*)0);				fprint(2, "can't exec diff: %r\n");				exits(0);			case -1:				fprint(2, "can't fork diff: %r\n");				break;			default:				while(waitpid() != -1)					;				break;			}		}		print("%s %s %lld\n", prtime(dir->mtime), buf, dir->length);		toggle ^= 1;		started = 1;		otime = dir->mtime;		free(dir);	}} voidlastbefore(ulong t, char *f, char *b, char *ndump){	Tm *tm;	Dir *dir;	int vers, try;	ulong t0, mtime; 	t0 = t;	if(verb)		print("%ld lastbefore %s\n", t0, f);	mtime = 0;	for(try=0; try<10; try++) {		tm = localtime(t);		sprint(b, "%s/%.4d/%.2d%.2d", ndump,			tm->year+1900, tm->mon+1, tm->mday);		dir = dirstat(b);		if(dir){			mtime = dir->mtime;			free(dir);		}		if(dir==nil || mtime > t0) {			if(verb)				print("%ld earlier %s\n", mtime, b);			t -= HOUR(24);			continue;		}		for(vers=0;; vers++) {			sprint(b, "%s/%.4d/%.2d%.2d%d", ndump,				tm->year+1900, tm->mon+1, tm->mday, vers+1);			dir = dirstat(b);			if(dir){				mtime = dir->mtime;				free(dir);			}			if(dir==nil || mtime > t0)				break;			if(verb)				print("%ld later %s\n", mtime, b);		}		sprint(b, "%s/%.4d/%.2d%.2d%s", ndump,			tm->year+1900, tm->mon+1, tm->mday, f);		if(vers)			sprint(b, "%s/%.4d/%.2d%.2d%d%s", ndump,				tm->year+1900, tm->mon+1, tm->mday, vers, f);		return;	}	strcpy(b, "XXX");	/* error */} char*prtime(ulong t){	static char buf[100];	char *b;	Tm *tm; 	if(uflag)		tm = gmtime(t);	else		tm = localtime(t);	b = asctime(tm);	memcpy(buf, b+4, 24);	buf[24] = 0;	return buf;} longstarttime(char *s){	Tm *tm;	long t, dt;	int i, yr, mo, da; 	t = time(0);	if(s == 0)		return t;	for(i=0; s[i]; i++)		if(s[i] < '0' || s[i] > '9') {			fprint(2, "bad start time: %s\n", s);			return t;		}	if(strlen(s)==6){		yr = (s[0]-'0')*10 + s[1]-'0';		mo = (s[2]-'0')*10 + s[3]-'0' - 1;		da = (s[4]-'0')*10 + s[5]-'0';		if(yr < 70)			yr += 100;	}else if(strlen(s)==8){		yr = (((s[0]-'0')*10 + s[1]-'0')*10 + s[2]-'0')*10 + s[3]-'0';		yr -= 1900;		mo = (s[4]-'0')*10 + s[5]-'0' - 1;		da = (s[6]-'0')*10 + s[7]-'0';	}else{		fprint(2, "bad start time: %s\n", s);		return t;	}	t = 0;	dt = YEAR(10);	for(i=0; i<50; i++) {		tm = localtime(t+dt);		if(yr > tm->year ||		  (yr == tm->year && mo > tm->mon) ||		  (yr == tm->year && mo == tm->mon) && da > tm->mday) {			t += dt;			continue;		}		dt /= 2;		if(dt == 0)			break;	}	t += HOUR(12);	/* .5 day to get to noon of argument */	return t;}