hgfs: allow "tip" as revision, do perm checking

sys/src/cmd/hgfs/fs.c

@@ -147,10 +147,10 @@ fsmkqid(Qid *q, int level, void *aux)
 		break;
 	case Qtree:
 		nd = aux;
-		if(nd->hash){
+		if(nd->down){
-			q->type = 0;
-		} else {
 			q->type = QTDIR;
+		} else {
+			q->type = 0;
 		}
 		q->path = nd->path;
 		q->vers = 0;
@@ -300,6 +300,8 @@ findrev(Revlog *rl, char *name)
 	int n, i, rev;
 	char *s;
 
+	if(strcmp(name, "tip") == 0)
+		return rl->nmap-1;
 	rev = strtol(name, &s, 10);
 	if(s > name && (*s == 0 || ispunct(*s)))
 		return rev;
@@ -452,7 +454,18 @@ fsdestroyfid(Fid *fid)
 static void
 fsopen(Req *r)
 {
+	Revfile *rf;
+
+	rf = r->fid->aux;
+	switch(r->ifcall.mode & 3){
+	case OEXEC:
+		if(rf->node == nil || rf->node->mode != 'x')
+			break;
+	case OREAD:
 		respond(r, nil);
+		return;
+	}
+	respond(r, "permission denied");
 }
 
 static int
@@ -495,17 +508,16 @@ static void
 fsread(Req *r)
 {
 	Revfile *rf;
+	char buf[MAXPATH];
+	Revlog rl;
+	char *s;
+	int i, n;
 
 	rf = r->fid->aux;
-	if(r->fid->qid.type == QTDIR){
 	switch(rf->level){
-		default:
-			respond(r, "bug in fsread");
-			return;
 	case Qroot:
 		revlogupdate(&changelog);
 		revlogupdate(&manifest);
-
 		dirread9p(r, rootgen, nil);
 		respond(r, nil);
 		return;
@@ -513,34 +525,11 @@ fsread(Req *r)
 		dirread9p(r, revgen, rf->info);
 		respond(r, nil);
 		return;
-		case Qtree:
-		case Qfiles:
-		case Qchanges:
-			dirread9p(r, treegen, rf->node->down);
-			respond(r, nil);
-			return;
-		}
-	} else {
-		char buf[MAXPATH];
-		Revlog rl;
-		char *s;
-		int i, n;
-
-		switch(rf->level){
-		default:
-			respond(r, "bug in fsread");
-			return;
-		case Qlog:
-			if(rf->fd >= 0)
-				break;
-			if((rf->fd = revlogopentemp(&changelog, hashrev(&changelog, rf->info->chash))) < 0){
-				responderror(r);
-				return;
-			}
-			break;
 	case Qrev1:
 	case Qrev2:
 		s = nil;
+		if(rf->buf)
+			goto Strgen;
 		if((i = hashrev(&changelog, rf->info->chash)) >= 0){
 			if(rf->level == Qrev1)
 				i = changelog.map[i].p1rev;
@@ -550,6 +539,14 @@ fsread(Req *r)
 				snprint(s = buf, sizeof(buf), "%d.%H", i, changelog.map[i].hash);
 		}
 		goto Strgen;
+	case Qlog:
+		if(rf->fd >= 0)
+			goto Fdgen;
+		if((rf->fd = revlogopentemp(&changelog, hashrev(&changelog, rf->info->chash))) < 0){
+			responderror(r);
+			return;
+		}
+		goto Fdgen;
 	case Qwho:
 		s = rf->info->who;
 		goto Strgen;
@@ -562,8 +559,15 @@ fsread(Req *r)
 		respond(r, nil);
 		return;
 	case Qtree:
+		if(rf->node->down){
+	case Qfiles:
+	case Qchanges:
+			dirread9p(r, treegen, rf->node->down);
+			respond(r, nil);
+			return;
+		}
 		if(rf->fd >= 0)
-				break;
+			goto Fdgen;
 		nodepath(seprint(buf, buf+sizeof(buf), ".hg/store/data"), buf+sizeof(buf), rf->node);
 		if(revlogopen(&rl, buf, OREAD) < 0){
 			responderror(r);
@@ -575,15 +579,16 @@ fsread(Req *r)
 			return;
 		}
 		revlogclose(&rl);
-			break;
+	Fdgen:
-		}
 		if((n = pread(rf->fd, r->ofcall.data, r->ifcall.count, r->ifcall.offset)) < 0){
 			responderror(r);
 			return;
 		}
 		r->ofcall.count = n;
 		respond(r, nil);
+		return;
 	}
+	respond(r, "bug in fsread");
 }
 
 Srv fs =