libndb: cleanup

sys/src/libndb/csgetval.c

@@ -14,15 +14,12 @@ char*
 csgetvalue(char *netroot, char *attr, char *val, char *rattr, Ndbtuple **pp)
 {
 	Ndbtuple *t, *first, *last;
-	int n, linefound;
 	char line[1024];
-	int fd;
-	int oops = 0;
+	int fd, n;
 	char *rv;
 
-	if(pp)
+	if(pp != nil)
 		*pp = nil;
-	rv = nil;
 
 	if(netroot)
 		snprint(line, sizeof(line), "%s/cs", netroot);
@@ -30,17 +27,17 @@ csgetvalue(char *netroot, char *attr, char *val, char *rattr, Ndbtuple **pp)
 		strcpy(line, "/net/cs");
 	fd = open(line, ORDWR);
 	if(fd < 0)
-		return 0;
+		return nil;
 	seek(fd, 0, 0);
 	snprint(line, sizeof(line), "!%s=%s %s=*", attr, val, rattr);
 	if(write(fd, line, strlen(line)) < 0){
 		close(fd);
-		return 0;
+		return nil;
 	}
 	seek(fd, 0, 0);
 
-	first = last = 0;
-	linefound = 0;
+	rv = nil;
+	first = last = nil;
 	for(;;){
 		n = read(fd, line, sizeof(line)-2);
 		if(n <= 0)
@@ -49,35 +46,22 @@ csgetvalue(char *netroot, char *attr, char *val, char *rattr, Ndbtuple **pp)
 		line[n+1] = 0;
 
 		t = _ndbparseline(line);
-		if(t == 0)
+		if(t == nil)
 			continue;
-		if(first)
+		if(first != nil)
 			last->entry = t;
 		else
 			first = t;
-		last = t;
-
-		while(last->entry)
-			last = last->entry;
-
-		for(; t; t = t->entry){
-			if(linefound == 0){
-				if(strcmp(rattr, t->attr) == 0){
-					linefound = 1;
-					rv = strdup(t->val);
-				}
-			}
-		}
+		do {
+			last = t;
+			if(rv == nil && strcmp(rattr, t->attr) == 0)
+				rv = strdup(t->val);
+			t = t->entry;
+		} while(t != nil);
 	}
 	close(fd);
 
-	if(oops){
-		werrstr("buffer too short");
-		ndbfree(first);
-		return nil;
-	}
-
-	if(pp){
+	if(pp != nil){
 		setmalloctag(first, getcallerpc(&netroot));
 		*pp = first;
 	} else

sys/src/libndb/dnsquery.c

@@ -129,17 +129,14 @@ doquery(int fd, char *dn, char *type)
 
 		t = _ndbparseline(buf);
 		if(t != nil){
-			if(first)
+			if(first != nil)
 				last->entry = t;
 			else
 				first = t;
 			last = t;
-
-			while(last->entry)
+			while(last->entry != nil)
 				last = last->entry;
 		}
 	}
-
-	ndbsetmalloctag(first, getcallerpc(&fd));
 	return first;
 }

sys/src/libndb/ndbdiscard.c

@@ -25,6 +25,5 @@ ndbdiscard(Ndbtuple *t, Ndbtuple *a)
 	a->entry = nil;
 	ndbfree(a);
 
-	ndbsetmalloctag(t, getcallerpc(&t));
 	return t;
 }

sys/src/libndb/ndbfree.c

@@ -71,6 +71,6 @@ ndbnew(char *attr, char *val)
 void
 ndbsetmalloctag(Ndbtuple *t, uintptr tag)
 {
-	for(; t; t=t->entry)
+	for(; t != nil; t=t->entry)
 		setmalloctag(t, tag);
 }

sys/src/libndb/ndbgetval.c

@@ -7,7 +7,7 @@
  *  search for a tuple that has the given 'attr=val' and also 'rattr=x'.
  *  copy 'x' into 'buf' and return the whole tuple.
  *
- *  return 0 if not found.
+ *  return nil if not found.
  */
 char*
 ndbgetvalue(Ndb *db, Ndbs *s, char *attr, char *val, char *rattr, Ndbtuple **pp)
@@ -21,32 +21,15 @@ ndbgetvalue(Ndb *db, Ndbs *s, char *attr, char *val, char *rattr, Ndbtuple **pp)
 	if(pp)
 		*pp = nil;
 	t = ndbsearch(db, s, attr, val);
-	while(t){
-		/* first look on same line (closer binding) */
-		nt = s->t;
-		for(;;){
-			if(strcmp(rattr, nt->attr) == 0){
-				rv = strdup(nt->val);
-				if(pp != nil)
-					*pp = t;
-				else
-					ndbfree(t);
-				return rv;
-			}
-			nt = nt->line;
-			if(nt == s->t)
-				break;
-		}
-		/* search whole tuple */
-		for(nt = t; nt; nt = nt->entry){
-			if(strcmp(rattr, nt->attr) == 0){
-				rv = strdup(nt->val);
-				if(pp != nil)
-					*pp = t;
-				else
-					ndbfree(t);
-				return rv;
-			}
+	while(t != nil){
+		nt = ndbfindattr(t, s->t, rattr);
+		if(nt != nil){
+			rv = strdup(nt->val);
+			if(pp != nil)
+				*pp = t;
+			else
+				ndbfree(t);
+			return rv;
 		}
 		ndbfree(t);
 		t = ndbsnext(s, attr, val);

sys/src/libndb/ndbhash.c

@@ -123,26 +123,22 @@ ndbsearch(Ndb *db, Ndbs *s, char *attr, char *val)
 	memset(s, 0, sizeof(*s));
 	if(_ndbcachesearch(db, s, attr, val, &t) == 0){
 		/* found in cache */
-		if(t != nil){
-			ndbsetmalloctag(t, getcallerpc(&db));
-			return t;	/* answer from this file */
-		}
+		if(t != nil)
+			goto out;
 		if(db->next == nil)
 			return nil;
 		t = ndbsearch(db->next, s, attr, val);
-		ndbsetmalloctag(t, getcallerpc(&db));
-		return t;
+		goto out;
 	}
 
 	s->db = db;
 	s->hf = hf;
-	if(s->hf){
+	if(s->hf != nil){
 		s->ptr = ndbhash(val, s->hf->hlen)*NDBPLEN;
 		p = hfread(s->hf, s->ptr+NDBHLEN, NDBPLEN);
-		if(p == 0){
+		if(p == nil){
 			t = _ndbcacheadd(db, s, attr, val, nil);
-			ndbsetmalloctag(t, getcallerpc(&db));
-			return t;
+			goto out;
 		}
 		s->ptr = NDBGETP(p);
 		s->type = Cptr1;
@@ -153,17 +149,17 @@ ndbsearch(Ndb *db, Ndbs *s, char *attr, char *val)
 		/* advance search to next db file */
 		s->ptr = NDBNAP;
 		_ndbcacheadd(db, s, attr, val, nil);
-		if(db->next == 0)
+		if(db->next == nil)
 			return nil;
 		t = ndbsearch(db->next, s, attr, val);
-		ndbsetmalloctag(t, getcallerpc(&db));
-		return t;
+		goto out;
 	} else {
 		s->ptr = 0;
 		s->type = Dptr;
 	}
 	t = ndbsnext(s, attr, val);
 	_ndbcacheadd(db, s, attr, val, (t != nil && s->db == db)?t:nil);
+out:
 	ndbsetmalloctag(t, getcallerpc(&db));
 	return t;
 }
@@ -173,7 +169,7 @@ match(Ndbtuple *t, char *attr, char *val)
 {
 	Ndbtuple *nt;
 
-	for(nt = t; nt; nt = nt->entry)
+	for(nt = t; nt != nil; nt = nt->entry)
 		if(strcmp(attr, nt->attr) == 0
 		&& strcmp(val, nt->val) == 0)
 			return nt;
@@ -200,12 +196,10 @@ ndbsnext(Ndbs *s, char *attr, char *val)
 				break;
 			t = ndbparse(db);
 			s->ptr = Boffset(&db->b);
-			if(t == 0)
+			if(t == nil)
 				break;
-			if(s->t = match(t, attr, val)){
-				ndbsetmalloctag(t, getcallerpc(&s));
-				return t;
-			}
+			if((s->t = match(t, attr, val)) != nil)
+				goto out;
 			ndbfree(t);
 		} else if(s->type == Cptr){
 			if(Bseek(&db->b, s->ptr, 0) < 0)
@@ -213,18 +207,16 @@ ndbsnext(Ndbs *s, char *attr, char *val)
 			s->ptr = s->ptr1;
 			s->type = Cptr1;
 			t = ndbparse(db);
-			if(t == 0)
+			if(t == nil)
 				break;
-			if(s->t = match(t, attr, val)){
-				ndbsetmalloctag(t, getcallerpc(&s));
-				return t;
-			}
+			if((s->t = match(t, attr, val)) != nil)
+				goto out;
 			ndbfree(t);
 		} else if(s->type == Cptr1){
 			if(s->ptr & NDBCHAIN){	/* hash chain continuation */
 				s->ptr &= ~NDBCHAIN;
 				p = hfread(s->hf, s->ptr+NDBHLEN, 2*NDBPLEN);
-				if(p == 0)
+				if(p == nil)
 					break;
 				s->ptr = NDBGETP(p);
 				s->ptr1 = NDBGETP(p+NDBPLEN);
@@ -234,12 +226,10 @@ ndbsnext(Ndbs *s, char *attr, char *val)
 					break; 
 				s->ptr = NDBNAP;
 				t = ndbparse(db);
-				if(t == 0)
+				if(t == nil)
 					break;
-				if(s->t = match(t, attr, val)){
-					ndbsetmalloctag(t, getcallerpc(&s));
-					return t;
-				}
+				if((s->t = match(t, attr, val)) != nil)
+					goto out;
 				ndbfree(t);
 				break;
 			}
@@ -247,14 +237,14 @@ ndbsnext(Ndbs *s, char *attr, char *val)
 	}
 
 nextfile:
-
 	/* nothing left to search? */
 	s->ptr = NDBNAP;
-	if(db->next == 0)
-		return 0;
+	if(db->next == nil)
+		return nil;
 
 	/* advance search to next db file */
 	t = ndbsearch(db->next, s, attr, val);
+out:
 	ndbsetmalloctag(t, getcallerpc(&s));
 	return t;
 }

sys/src/libndb/ndbparse.c

@@ -30,9 +30,9 @@ ndbparse(Ndb *db)
 	Ndbtuple *first, *last;
 	int len;
 
-	first = last = 0;
+	first = last = nil;
 	for(;;){
-		if((line = Brdline(&db->b, '\n')) == 0)
+		if((line = Brdline(&db->b, '\n')) == nil)
 			break;
 		len = Blinelen(&db->b);
 		if(line[len-1] != '\n')
@@ -42,15 +42,15 @@ ndbparse(Ndb *db)
 			break;
 		}
 		t = _ndbparseline(line);
-		if(t == 0)
+		if(t == nil)
 			continue;
 		setmalloctag(t, getcallerpc(&db));
-		if(first)
+		if(first != nil)
 			last->entry = t;
 		else
 			first = t;
 		last = t;
-		while(last->entry)
+		while(last->entry != nil)
 			last = last->entry;
 	}
 	ndbsetmalloctag(first, getcallerpc(&db));

sys/src/libndb/ndbreorder.c

@@ -4,7 +4,7 @@
 #include <ndb.h>
 
 /*
- *  reorder the tuple to put x's line first in the entry and x fitst in its line
+ *  reorder the tuple to put x's line first in the entry and x first in its line
  */
 Ndbtuple*
 ndbreorder(Ndbtuple *t, Ndbtuple *x)