/*  * This file is part of the UCB release of Plan 9. It is subject to the license * terms in the LICENSE file found in the top-level directory of this * distribution and at http://akaros.cs.berkeley.edu/files/Plan9License. No * part of the UCB release of Plan 9, including this file, may be copied, * modified, propagated, or distributed except according to the terms contained * in the LICENSE file. */ #include <u.h>#include <libc.h>#include <venti.h> char *VtServerLog = "libventi/server"; int ventilogging;#define log	not_the_log_library_call static char Eremoved[] = "[removed]"; enum{	/* defaults */	LogChunkSize = 8192,	LogSize = 65536}; static struct {	QLock lk;	VtLog *hash[1024];} vl; static uinthash(char *s){	uint h;	uchar *p; 	h = 0;	for(p=(uchar*)s; *p; p++)		h = h*37 + *p;	return h;} char**vtlognames(int *pn){	int i, nname, size;	VtLog *l;	char **s, *a, *e;		qlock(&vl.lk);	size = 0;	nname = 0;	for(i=0; i<nelem(vl.hash); i++)	for(l=vl.hash[i]; l; l=l->next){		nname++;		size += strlen(l->name)+1;	}		s = vtmalloc(nname*sizeof(char*)+size);	a = (char*)(s+nname);	e = (char*)s+nname*sizeof(char*)+size; 	nname = 0;	for(i=0; i<nelem(vl.hash); i++)	for(l=vl.hash[i]; l; l=l->next){		strcpy(a, l->name);		s[nname++] = a;		a += strlen(a)+1;	}	*pn = nname;	assert(a == e);	qunlock(&vl.lk); 	return s;} VtLog*vtlogopen(char *name, uint size){	uint h;	int i, nc;	char *p;	VtLog *l, *last; 	if(!ventilogging)		return nil; 	h = hash(name)%nelem(vl.hash);	qlock(&vl.lk);	last = nil;	for(l=vl.hash[h]; l; last=l, l=l->next)		if(strcmp(l->name, name) == 0){			if(last){	/* move to front */				last->next = l->next;				l->next = vl.hash[h];				vl.hash[h] = l;			}			l->ref++;			qunlock(&vl.lk);			return l;		} 	if(size == 0){		qunlock(&vl.lk);		return nil;	} 	/* allocate */	nc = (size+LogChunkSize-1)/LogChunkSize;	l = vtmalloc(sizeof *l + nc*(sizeof(*l->chunk)+LogChunkSize) + strlen(name)+1);	memset(l, 0, sizeof *l);	l->chunk = (VtLogChunk*)(l+1);	l->nchunk = nc;	l->w = l->chunk;	p = (char*)(l->chunk+nc);	for(i=0; i<nc; i++){		l->chunk[i].p = p;		l->chunk[i].wp = p;		p += LogChunkSize;		l->chunk[i].ep = p;	}	strcpy(p, name);	l->name = p;		/* insert */	l->next = vl.hash[h];	vl.hash[h] = l;	l->ref++;		l->ref++;	qunlock(&vl.lk);	return l;} voidvtlogclose(VtLog *l){	if(l == nil)		return; 	qlock(&vl.lk);	if(--l->ref == 0){		/* must not be in hash table */		assert(l->name == Eremoved);		free(l);	}else		assert(l->ref > 0);	qunlock(&vl.lk);} voidvtlogremove(char *name){	uint h;	VtLog *last, *l; 	h = hash(name)%nelem(vl.hash);	qlock(&vl.lk);	last = nil;	for(l=vl.hash[h]; l; last=l, l=l->next)		if(strcmp(l->name, name) == 0){			if(last)				last->next = l->next;			else				vl.hash[h] = l->next;			l->name = Eremoved;			l->next = nil;			qunlock(&vl.lk);			vtlogclose(l);			return;		}	qunlock(&vl.lk);} static inttimefmt(Fmt *fmt){	static uvlong t0;	uvlong t; 	if(t0 == 0)		t0 = nsec();	t = nsec()-t0;	return fmtprint(fmt, "T+%d.%04d", (uint)(t/1000000000), (uint)(t%1000000000)/100000);} voidvtlogvprint(VtLog *l, char *fmt, va_list arg){	int n;	char *p;	VtLogChunk *c;	static int first = 1; 	if(l == nil)		return;			if(first){		fmtinstall('T', timefmt);		first = 0;	}				qlock(&l->lk);	c = l->w;	n = c->ep - c->wp;	if(n < 512){		c++;		if(c == l->chunk+l->nchunk)			c = l->chunk;		c->wp = c->p;		l->w = c;	}	p = vseprint(c->wp, c->ep, fmt, arg);	if(p)		c->wp = p;	qunlock(&l->lk);} voidvtlogprint(VtLog *l, char *fmt, ...){	va_list arg;		if(l == nil)		return;			va_start(arg, fmt);	vtlogvprint(l, fmt, arg);	va_end(arg);} voidvtlog(char *name, char *fmt, ...){	VtLog *l;	va_list arg; 	l = vtlogopen(name, LogSize);	if(l == nil)		return;	va_start(arg, fmt);	vtlogvprint(l, fmt, arg);	va_end(arg);	vtlogclose(l);} voidvtlogdump(int fd, VtLog *l){	int i;	VtLogChunk *c; 	if(l == nil)		return;			c = l->w;	for(i=0; i<l->nchunk; i++){		if(++c == l->chunk+l->nchunk)			c = l->chunk;		write(fd, c->p, c->wp-c->p);	}}