code: plan9front

Download patch

ref: ab4b7c2573b35062f211c2548ff20031f998cc8e
parent: 497daed116714a8c3f91162fe02ca81ad33bb6fa
author: cinap_lenrek <cinap_lenrek@felloff.net>
date: Wed Jul 22 23:24:39 EDT 2015

ip/httpfile: fix flushes, fix concurrent reads, set error string

Tflush handling was wrong, we cannot respond to the old
request if we have not actually removed the req from the
in progress block queue.

when reads are issued concurrently, we have to set b->len
before the block is inserted into the inprogress list.
otherwise findblock() is unable to find it and no requests
can be queued on the block. this caused the same offset
to be downloaded multiple times.

set the errstr in getrange() so in case of an error, we dont
get some random previous error string.

--- a/sys/src/cmd/ip/httpfile.c
+++ b/sys/src/cmd/ip/httpfile.c
@@ -100,6 +100,8 @@
 			*l = r->aux;
 			if(*l == nil)
 				b->erq = l;
+			r->aux = nil;
+			respond(r, "interrupted");
 			return;
 		}
 	}
@@ -205,10 +207,6 @@
 	int fd, cfd;
 	uchar *data;
 
-	b->len = Blocksize;
-	if(b->off + b->len > size)
-		b->len = size - b->off;
-
 	if(debug)
 		print("getrange: %lld %lld\n", b->off, b->len);
 
@@ -230,6 +228,8 @@
 		close(fd);
 		return nil;
 	}
+
+	werrstr("bad contentrange header");
 	if(readstring(cfd, buf, sizeof(buf)) <= 0){
 Badrange:
 		close(cfd);
@@ -244,6 +244,7 @@
 
 	/* read body data */
 	data = emalloc9p(b->len);
+	werrstr("body data truncated");
 	if(readfile(fd, (char*)data, b->len) != b->len){
 		close(fd);
 		free(data);
@@ -410,6 +411,9 @@
 	if((b = findblock(&inprogress, r->ifcall.offset)) == nil){
 		b = emalloc9p(sizeof(Block));
 		b->off = r->ifcall.offset - (r->ifcall.offset % Blocksize);
+		b->len = Blocksize;
+		if(b->off + b->len > size)
+			b->len = size - b->off;
 		addblock(&inprogress, b);
 		if(inprogress.first == b)
 			sendp(httpchan, b);
@@ -467,10 +471,11 @@
 		switch(r->ifcall.type){
 		case Tflush:
 			o = r->oldreq;
-			b = findblock(&inprogress, o->ifcall.offset);
-			if(b != nil)
-				delreq(b, o);
-			respond(o, "interrupted");
+			if(o->ifcall.type == Tread){
+				b = findblock(&inprogress, o->ifcall.offset);
+				if(b != nil)
+					delreq(b, o);
+			}
 			respond(r, nil);
 			break;
 		case Tread: