Import sources from 2011-03-30 iso image

1 files changed, 256 insertions, 0 deletions

diff --git a/sys/src/libventi/log.c b/sys/src/libventi/log.c
new file mode 100755
index 000000000..80a1d4787
--- /dev/null
+++ b/sys/src/libventi/log.c
@@ -0,0 +1,256 @@
+#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 uint
+hash(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;
+}
+
+void
+vtlogclose(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);
+}
+
+void
+vtlogremove(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 int
+timefmt(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);
+}
+
+void
+vtlogvprint(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);
+}
+
+void
+vtlogprint(VtLog *l, char *fmt, ...)
+{
+	va_list arg;
+	
+	if(l == nil)
+		return;
+		
+	va_start(arg, fmt);
+	vtlogvprint(l, fmt, arg);
+	va_end(arg);
+}
+
+void
+vtlog(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);
+}
+
+void
+vtlogdump(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);
+	}
+}
+