Re: [evolution-patches] Patch: Camel stream filter waits properly for slow streams

[Philip Van Hoof <spam pvanhoof be>]

Adding some people and mailing lists in CC

Reattaching patch for Evolution-hackers mailing list.

Please bring this upstream too, José

Response from Jeffrey:

jeff_ yea, you should compare against -1
jeff_ as long as it returns >0, it wrote all the data
jeff_ -1 is error
jeff_ 0 is EOF maybe
jeff_ if write even returns 0 ever


On Tue, 2008-05-20 at 16:10 +0200, José Dapena Paz wrote:
> 	Hi,
> 
> 	This patch for tinymail modifies a bit the implementation of do_write
> method in camel_stream_filter, to make it not fail simply because the
> stream is slow. In my case I'm getting problems writting to a bluetooth
> stream, as it sometimes writes less than the full buffer, and then the
> stream filter returns -1.
> 
> 	Anyway, it seems that my code adds an active wait. How could I fix
> this? Any safe idea?
> 
> 	Changelog entry would be:
> * libtinymail-camel/camel-lite/camel/camel-stream-filter.c:
> 	* (do_write): if the camel_stream_write call does not write the
> 	  full buffer but it's not due to an error, then loop to go on 
> 	  writing the stream.




-- 
Philip Van Hoof, freelance software developer
home: me at pvanhoof dot be 
gnome: pvanhoof at gnome dot org 
http://pvanhoof.be/blog
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Index: libtinymail-camel/camel-lite/camel/camel-stream-filter.c
===================================================================
--- libtinymail-camel/camel-lite/camel/camel-stream-filter.c	(revision 3671)
+++ libtinymail-camel/camel-lite/camel/camel-stream-filter.c	(working copy)
@@ -290,6 +290,7 @@
 	struct _filter *f;
 	size_t presize, len, left = n;
 	char *buffer, realbuffer[READ_SIZE+READ_PAD];
+	size_t written = 0;
 
 	p->last_was_read = FALSE;
 
@@ -321,8 +322,13 @@
 			f = f->next;
 		}
 
-		if (camel_stream_write(filter->source, buffer, len) != len)
-			return -1;
+		for (written = 0; written < len;) {
+			size_t just_written;
+			just_written = camel_stream_write (filter->source, buffer + written, len - written);
+			if (just_written == -1)
+				return -1;
+			written += just_written;
+		}
 	}
 
 	g_check(p->realbuffer);