41831 - ImgDWriteReady/ImgDWrite behavior wrong

Status: VERIFIED FIXED

(Core :: Graphics: ImageLib, defect, P3)

Description

[tor]

libimg doesn't seem to respect the return value from a decoders'
ImgDWriteReady.  Here's a trace of the calls into a decoder from
a typical session (ImgDWriteReady just returning 1024 for illustration
purposes):

MNG::Create()
MNG::MNGDecoder()
MNG::ImgDInit()
MNG::ImgDWrite(128)
MNG::ImgDWriteReady() = 1024
MNG::ImgDWrite(2048)
Assertion failed: len<MOZ_MNG_BUFSIZE-imng_p->bytesBuffered, file
/cs/src/mozilla/mozilla/modules/libimg/mngcom/nsMNGDecoder.cpp, line 114

Notice that the first call to ImgDWrite occurs before libimg even checks
how much data the decoder is ready to accept.  After that it does get
around to calling ImgDWriteReady, but ignores the response and tries dumping
twice as much data into the decoder.

This is causing problems with MNG integration.  I can work around it for
development by having a very large internal buffer, but that's wasteful and
fragile.

Comment 1

[johng]

triage team:
cool, but we can live without it in first release.  nsbeta3-

Comment 2

[pnunn]

All pnunn bugs reassigned to Pav, who is taking over
the imglib.

Comment 3

[Stuart Parmenter]

code no longer used.  marking fixed.

Comment 4

[Terri Preston]

Okay, verified