[ expat-Bugs-580503 ] 1.95.2 Reuses Buffer if isFinal != 0

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Bugs item #580503, was opened at 2002-07-12 05:47
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Category: None
Group: None
Status: Open
Resolution: None
Priority: 5
Submitted By: Ari Johnson (ari_j)
Assigned to: Nobody/Anonymous (nobody)
Summary: 1.95.2 Reuses Buffer if isFinal != 0

Initial Comment:
In expat 1.95.2 (the latest version for which a 
FreeBSD package is available), calling 
XML_ParseBuffer() or XML_Parse() with isFinal != 0 
causes the previously-parsed buffer to be parsed, 
at least partially, again.  For example, say that I'm 
sending it chunks of 1024 bytes at a time, and the 
last root tag of my XML file is <test>.  Let's say 
that the last buffer chunk I sent it was as follows:
--
<nodeN>value</nodeN>
<data/>
</test>
--
The next time I call XML_ParseBuffer() or XML_Parse
(), I get the full complement of startElement, 
endElement, and characterData events for 
<nodeN>.  This occurs after I've received the 
<test> endElement event.  Moreover, the error 
occurs whether I send len = 0 to XML_Parse*() or if I 
actually send data to it.

Is this a known bug?  Is it fixed in a newer version?  
I couldn't find any references to it on the bug list, 
open or closed; nor in the CVS log for xmlparser.c.


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>Comment By: Karl Waclawek (kwaclaw)
Date: 2002-07-12 16:37

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Try removing the call for getting a zero sized buffer:
  char *buff = XML_GetBuffer(p, 0);
or change the size parameter back to 1024.
Does that have any effect?


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Comment By: Ari Johnson (ari_j)
Date: 2002-07-12 16:29

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Just an update...the same thing happens when I don't 
set isFinal in the error-producing call, or of course if I 
feed it more text (since this is just after the </root> tag 
has been read).

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Comment By: Ari Johnson (ari_j)
Date: 2002-07-12 16:10

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I apologize for a mistake; the error it returns is 9 -> 
junk after document element.  I was calling 
GetErrorCode wrong.  Anyhow...

---
int c = 1024;
while(c == 1024) {
  char *buff = XML_GetBuffer(p, 1024);
  if(!buff)
    ...
  c = read(fd, buff, 1024);
  if(c < 0)
    ...
  if(!XML_ParseBuffer(p, c, 0))
    ...
}

...

void handle_end_element(...) {
  if([it was the root element]) {
    char *buff = XML_GetBuffer(p, 0);
    if(!XML_ParseBuffer(p, 0, 1))
      /* This is where the error occurs. */
  }
}


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Comment By: Karl Waclawek (kwaclaw)
Date: 2002-07-12 15:42

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In that case please post a small example that can
produce the behaviour you have reported.

Karl

----------------------------------------------------------------------

Comment By: Ari Johnson (ari_j)
Date: 2002-07-12 15:22

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Same thing occurs with the current CVS.  This even 
occurs when I actually send XML_Parse*() some text to 
process.  And to make things worse, XML_Parse() 
returns false since it's trying to parse text past the close 
tag of my root element, but the error code is set to 0.


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Comment By: Karl Waclawek (kwaclaw)
Date: 2002-07-12 09:07

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Please retest with 1.95.3 or the current CVS.
Also, we are planning to release 1.95.4 today,
so if this is a bug, let's find out ASAP.

Karl

----------------------------------------------------------------------

Comment By: Karl Waclawek (kwaclaw)
Date: 2002-07-12 08:52

Message:
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user_id=290026

Please retest with 1.95.3 or the current CVS.
Also, we are planning to release 1.95.4 today,
so if this is a bug, let's find out ASAP.

Karl

----------------------------------------------------------------------

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