[xml] calling xmlXIncludeProcess after xmlParseFile generates error

["Christopher J. Grayce" <cgrayce aleks com>]

Dear All,

   I would appreciate any enlightment on why this program works as expected...

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#include <stdlib.h>
#include <stdio.h>
#include <libxml/parser.h>
#include <libxml/xinclude.h>

int main(int argc, char *argv[]) {
  
  char *path = argv[1] ;
  xmlDoc *doc ;
  xmlParserOption options = XML_PARSE_XINCLUDE ;

  doc = xmlReadFile(path,NULL,options) ;
  xmlXIncludeProcess(doc) ;
  xmlDocFormatDump(stdout,doc,1) ;

  return(0) ;
}
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...but THIS program generates a segmentation violation:

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#include <stdlib.h>
#include <stdio.h>
#include <libxml/parser.h>
#include <libxml/xinclude.h>

int main(int argc, char *argv[]) {
  
  char *path = argv[1] ;
  xmlDoc *doc ;

  doc = xmlParseFile(path) ;
  xmlXIncludeProcess(doc) ;
  xmlDocFormatDump(stdout,doc,1) ;

  return(0) ;
}
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   Here is the stack trace after the SIGSEGV:

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Program received signal SIGSEGV, Segmentation fault.
[Switching to Thread 1075296320 (LWP 4680)]
0x4010b71b in xmlDictOwns (dict=0x805be20, str=0x805b828 "what's up, Doc?")
    at dict.c:616
616             if ((str >= pool->array) && (str <= pool->free))
(gdb) where
#0  0x4010b71b in xmlDictOwns (dict=0x805be20, str=0x805b828 "what's up, Doc?")
    at dict.c:616
#1  0x400763f7 in xmlFreeNodeList (cur=0x805bc88) at tree.c:3294
#2  0x40076379 in xmlFreeNodeList (cur=0x805bc28) at tree.c:3284
#3  0x40072fcb in xmlFreeDoc (cur=0x805bb28) at tree.c:1115
#4  0x400c2832 in xmlXIncludeLoadDoc (ctxt=0x805c0b8, url=0x804a7b8 "foo.xml", 
    nr=0) at xinclude.c:1582
#5  0x400c30dc in xmlXIncludeLoadNode (ctxt=0x805c0b8, nr=0) at xinclude.c:1867
#6  0x400c39d3 in xmlXIncludeDoProcess (ctxt=0x805c0b8, doc=0x805bd78, 
    tree=0x805bf88) at xinclude.c:2140
#7  0x400c3af3 in xmlXIncludeProcessFlags (doc=0x805bd78, flags=0)
    at xinclude.c:2200
#8  0x400c3b4b in xmlXIncludeProcess (doc=0x805bd78) at xinclude.c:2219
#9  0x08048526 in main (argc=2, argv=0xbfffdbe4) at curious.c:21
#10 0x42015574 in __libc_start_main () from /lib/tls/libc.so.6
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   Here is the XML file with the XInclude instruction:

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<?xml version="1.0"?>
<element xmlns:xi="http://www.w3.org/2003/XInclude";>
   <xi:include href="foo.xml" />
</element>
--------------------------------------------------------------------------------

   And here are the contents of "foo.xml" (to be included):

--------------------------------------------------------------------------------
<?xml version="1.0"?>
<element>what's up, Doc?</element>
--------------------------------------------------------------------------------

   Clearly I am missing something about when xmlParseFile versus
xmlReadFile should be used.

   I also wonder what the purpose of the third (options) argument to
xmlReadFile is.  Setting it to XML_PARSE_INCLUDE doesn't cause XInclude
processing to occur immediately after parsing, as I would have thought it
would. . .

   The version of libxml2 is 2.6.4, compiled from source (with no errors)
under RedHat 9.0.

   Thanks in advance,
   CJG