/* querystring.c

Break up a QUERY_STRING variable.

Output is in SETENV format, ready to be eval'd

Source: Steve Shipway. <http://www.steveshipway.org/software/utils/querystring.c> accessed 2011/5/17.

*/

#include <stdio.h>
#include <string.h>

parse( char *s 
       /* we can't use strtok since we are already using it at the higher level */
       {
	 char *vname;
	 char *val;
	 int c;
	 char buf[3];

	 if (!s) {
	   printf("X_ERR='Null phrase'\n");
	   return;
	 }
	 vname = s;
	 while (*s && (*s != '=')) s++;
	 if (!*s) {
	   printf("X_ERR='Null assignment'\n");
	   return;
	 }
	 *(s++) = '\0';

	 printf("%s='", vname);

	 for (val=s; *val; val++) {
	   switch (*val) {
	   case '%':
	     buf[0]=*(++val); buf[1]=*(++val); buf[2]='\0';
	     sscanf(buf, "%2x", &c);
	     break;
	   case '+':
	     c = ' ';
	     break;
	   default:
	     c = *val;
	   }

	   switch (c) {
	   case '\\': printf("\\\\"); break;
	   case '\'': printf("\\'"); break;
	   case '\n': printf("\\n"); break;
	   default:   putchar((char)c); break;
	   }
	 }

	 printf("'\n");
       }

main()
       {
	 char *query_string;
	 char *phrase;

	 query_string = (char *)getenv("QUERY_STRING");

	 if (!query_string) {
	   printf("X_ERR='QUERY_STRING not set'\n");
	   exit(0);
	 }

	 phrase = strtok(query_string, "&");
	 while (phrase) {
	   parse(phrase);
	   phrase = strtok((char *)0, "&");
	 }
       }