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found/fixed garp bug

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  • Subject: found/fixed garp bug
  • Date: Fri, 25 Feb 2000 01:00:13 -0600
Hi,

 We noticed the following bug in garp (from NAWIPS-5.4PL15)

 When bringing up the image selection dialog, the program would dump
core in certain data directory configurations.

 I traced it to the function SplitByDelimeter() in 
 $NAWIPS/garp/util/stringlist.c

 It allocates a fixed buffer (buf) of size 1024 bytes for string processing.
However, it is possible to overflow that if, for example, $SAT
is a long path and there are lots of image subdirectories.  This was
the case in our situation.

 I propose the following patch (below) to dynamically allocate
a buffer of the exact size needed.  Adds a bit of overhead but
I don't think SplitByDelimeter is called inside any time critical
loops.  Alternately, the fixed buffer could be made larger, but then
how large is enough?



---8<---- stringlist.patch ------------------------------------------------
*** garp/util/stringlist.c      Fri Feb 25 06:42:17 2000
--- garp/util/stringlist.c.new  Fri Feb 25 06:41:48 2000
***************
*** 244,250 ****
   * of parsed strings.
   */
  {
!       char            buf[1024], *token;
        char            **tList;
        int             i, count=1;
        int             verbose;
--- 244,250 ----
   * of parsed strings.
   */
  {
!       char            *buf, *token;
        char            **tList;
        int             i, count=1;
        int             verbose;
***************
*** 272,277 ****
--- 272,278 ----
   *    case when the first token is null. Replace NULL substrings with
   *    a space.
   */
+         buf = malloc (strlen(input) + 2);
        if ( strncmp ( input, delimeter, 1 ) == 0 ) {
            strcpy ( buf, " " );
            strcat ( buf, input );
***************
*** 288,293 ****
--- 289,295 ----
               tList[i] = strdup ( " " );
            token = strtok ( NULL, delimeter );
        }
+         free(buf);

  /*
   *    Return values.
---->8-----------------------------------------------------------------------


--------------------------------------------------------
 David Wojtowicz, Research Programmer
 Department of Atmospheric Sciences Computer Services
 University of Illinois at Urbana-Champaign
 email: address@hidden  phone: (217)333-8390
--------------------------------------------------------