195638 - [ASSERTION] 4.x NPP_WriteReady = 0 should not be an error

Status: RESOLVED DUPLICATE of bug 89270

(Core Graveyard :: Plug-ins, defect)

Description

[tenthumbs]

If 1) a 4.x plugin can only accept data at some fixed maximum rate, 2) the
network connection is faster than that rate, and 3) the plugin uses NPP_Write
and NPP_WriteReady then the plugin may well return 0 for NPP_WriteReady because
it cannot currently accept more data.

Mozilla treats this as an error, throws the assertion 

###!!! ASSERTION: WriteReady returned Zero: 'numtowrite', file
ns4xPluginInstance.cpp, line 413
Break: at file ns4xPluginInstance.cpp, line 413

and then cancels the stream.

The old 4.x plugin docs don't say zero is an error. It's also fairly common for
streams to block for a while. Mozilla's behavior seems incorrect.

I've also done a few test with a rate-limited proxy server and it certainly
appears that if the network is slower than the plugin then mozilla will succeed.
Success for a slow connection and failure for a fast one also seems incorrect.

Comment 1

[tenthumbs]

Setting the assertion keyword.

Comment 2

[Peter Lubczynski]

*** This bug has been marked as a duplicate of 89270 ***