text: /* err.c
   * Copyright (c) 2011, Peter Ohler
   * All rights reserved.
   */
  
  #include <stdarg.h>
  
  #include "err.h"
  
  void
  ox_err_set(Err e, VALUE clas, const char *format, ...) {
      va_list	ap;
  
      va_start(ap, format);
      e->clas = clas;
      vsnprintf(e->msg, sizeof(e->msg) - 1, format, ap);
      va_end(ap);
  }
  
  void
  ox_err_raise(Err e) {
      rb_raise(e->clas, "%s", e->msg);
  }
  
  void
  _ox_err_set_with_location(Err err, const char *msg, const char *xml, const char *current, const char* file, int line) {
      int	xline = 1;
      int	col = 1;
  
      for (; xml < current && '\n' != *current; current--) {
  	col++;
      }
      for (; xml < current; current--) {
  	if ('\n' == *current) {
  	    xline++;
  	}
      }
      ox_err_set(err, ox_parse_error_class, "%s at line %d, column %d [%s:%d]\n", msg, xline, col, file, line);
  }
  