parsing XML file in C

desxor · **Joined:** 01 Sep 2008 07:40 **Posts:** 31

i'm looking for a fairly straight forward way of parsing a basic XML file into an array, ive been trying to use strtok() but it is furiously frustrating. all i need to do is parse the dumb <values> and </values>

any help is much appreciated

aluigi · **Posted:** 19 Oct 2008 12:07

text files are a pain in C.
If the XML you want to parse is simple (like in the example you have posted) you can use a combination of pointers and strstr although probably this solution is not much different than strtok (most depends by your input file if <values> are one for each line or mixed and so on).
The alternative is using libxml bug I have never tried it.

AnonymousCoward · **Joined:** 24 Feb 2008 08:31 **Posts:** 10

Probably the most basic (but complete) library for parsing XML would be Expat: http://expat.sourceforge.net/

I've never used it personally, but it should work for what you're trying to do (and it's fairly lightweight too).

desxor · **Joined:** 01 Sep 2008 07:40 **Posts:** 31

ty AC, I found a simple solution online that i was able to modify for my needs, here is the original function (credit: happycoding.com author?)

Code:

char **split(char *string, char *delim) {
   char **tokens = NULL;
   char *working = NULL;
   char *token = NULL;
   int idx = 0;

   tokens  = malloc(sizeof(char *) * MAXTOKENS);
   if(tokens == NULL)
      return NULL;

   working = malloc(sizeof(char) * strlen(string) + 1);
   if(working == NULL)
      return NULL;

   strcpy(working, string);

   for(idx = 0; idx < MAXTOKENS; idx++)
      tokens[idx] = NULL;

   token = strtok(working, delim);
   idx = 0;

   while((idx < (MAXTOKENS - 1)) && (token != NULL)) {
      tokens[idx] = malloc(sizeof(char) * strlen(token) + 1);

      if(tokens[idx] != NULL) {
         strcpy(tokens[idx], token);
         idx++;
         token = strtok(NULL, delim);
      }
   }

   free(working);
   return tokens;
}

aluigi · **Posted:** 21 Oct 2008 12:45

some small tips which make the code more readable and shorter:
- you can avoid to use malloc + strcpy simply using strdup, example:
working = strdup(string);
tokens[idx] = strdup(token);
- you can allocating and zeroing tokens using: tokens = calloc(sizeof(char *), MAXTOKENS);
- if "tokens[idx] != NULL" do that stuff otherwise break or you could have an endless loop

desxor · **Joined:** 01 Sep 2008 07:40 **Posts:** 31

aluigi wrote:

some small tips which make the code more readable and shorter:
- you can avoid to use malloc + strcpy simply using strdup, example:
working = strdup(string);
tokens[idx] = strdup(token);
- you can allocating and zeroing tokens using: tokens = calloc(sizeof(char *), MAXTOKENS);
- if "tokens[idx] != NULL" do that stuff otherwise break or you could have an endless loop

ty for the advice, will do ;)

Luigi Auriemma

parsing XML file in C