text: #include <u.h>
  #include <libc.h>
  #include "libString.h"
  
  #undef isspace
  #define isspace(c) ((c)==' ' || (c)=='\t' || (c)=='\n')
  
  /* Get the next field from a String.  The field is delimited by white space,
   * single or double quotes.
   */
  String *
  s_parse(String *from, String *to)
  {
  	if (*from->ptr == '\0')
  		return 0;
  	if (to == 0)
  		to = s_new();
  	if (*from->ptr == '\'') {
  		from->ptr++;
  		for (;*from->ptr != '\'' && *from->ptr != '\0'; from->ptr++)
  			s_putc(to, *from->ptr);
  		if (*from->ptr == '\'')
  			from->ptr++;
  	} else if (*from->ptr == '"') {
  		from->ptr++;
  		for (;*from->ptr != '"' && *from->ptr != '\0'; from->ptr++)
  			s_putc(to, *from->ptr);
  		if (*from->ptr == '"')
  			from->ptr++;
  	} else {
  		for (;!isspace(*from->ptr) && *from->ptr != '\0'; from->ptr++)
  			s_putc(to, *from->ptr);
  	}
  	s_terminate(to);
  
  	/* crunch trailing white */
  	while(isspace(*from->ptr))
  		from->ptr++;
  
  	return to;
  }
  