usr/src/cmd/ipf/lib/common/getline.c

   1 /*
   2  * Copyright (C) 1993-2001 by Darren Reed.
   3  *
   4  * See the IPFILTER.LICENCE file for details on licencing.
   5  *
   6  * $Id: getline.c,v 1.3 2001/06/09 17:09:24 darrenr Exp $
   7  */
   8
   9 #include <stdio.h>
  10 #if !defined(__SVR4) && !defined(__GNUC__)
  11 #include <strings.h>
  12 #endif
  13 #include <string.h>
  14 #include "ipf.h"
  15
  16
  17 /*
  18  * Similar to fgets(3) but can handle '\\' and NL is converted to NUL.
  19  * Returns NULL if error occured, EOF encounterd or input line is too long.
  20  */
  21 char *
  22 getaline(char *str, size_t size, FILE *file, int *linenum)
  23 {
  24         char *p;
  25         int s, len;
  26
  27         do {
  28                 for (p = str, s = size; ; p += (len - 1), s -= (len - 1)) {
  29                         /*
  30                          * if an error occured, EOF was encounterd, or there
  31                          * was no room to put NUL, return NULL.
  32                          */
  33                         if (fgets(p, s, file) == NULL)
  34                                 return (NULL);
  35                         len = strlen(p);
  36                         if (p[len - 1] != '\n') {
  37                                 p[len] = '\0';
  38                                 break;
  39                         }
  40                         (*linenum)++;
  41                         p[len - 1] = '\0';
  42                         if (len < 2 || p[len - 2] != '\\')
  43                                 break;
  44                         else
  45                                 /*
  46                                  * Convert '\\' to a space so words don't
  47                                  * run together
  48                                  */
  49                                 p[len - 2] = ' ';
  50                 }
  51         } while (*str == '\0');
  52         return (str);
  53 }