libio/iogetline.c

   1 /* Copyright (C) 1993,1997,1998,2000,2001,2002 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Lesser General Public
   6    License as published by the Free Software Foundation; either
   7    version 2.1 of the License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public
  15    License along with the GNU C Library; if not, write to the Free
  16    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  17    02111-1307 USA.
  18
  19    As a special exception, if you link the code in this file with
  20    files compiled with a GNU compiler to produce an executable,
  21    that does not cause the resulting executable to be covered by
  22    the GNU Lesser General Public License.  This exception does not
  23    however invalidate any other reasons why the executable file
  24    might be covered by the GNU Lesser General Public License.
  25    This exception applies to code released by its copyright holders
  26    in files containing the exception.  */
  27
  28 #include "libioP.h"
  29 #include <string.h>
  30
  31 #if defined _LIBC || !_G_HAVE_IO_GETLINE_INFO
  32
  33 _IO_size_t
  34 _IO_getline (fp, buf, n, delim, extract_delim)
  35      _IO_FILE *fp;
  36      char *buf;
  37      _IO_size_t n;
  38      int delim;
  39      int extract_delim;
  40 {
  41   return INTUSE(_IO_getline_info) (fp, buf, n, delim, extract_delim,
  42                                    (int *) 0);
  43 }
  44 INTDEF(_IO_getline)
  45
  46 /* Algorithm based on that used by Berkeley pre-4.4 fgets implementation.
  47
  48    Read chars into buf (of size n), until delim is seen.
  49    Return number of chars read (at most n).
  50    Does not put a terminating '\0' in buf.
  51    If extract_delim < 0, leave delimiter unread.
  52    If extract_delim > 0, insert delim in output. */
  53
  54 _IO_size_t
  55 _IO_getline_info (fp, buf, n, delim, extract_delim, eof)
  56      _IO_FILE *fp;
  57      char *buf;
  58      _IO_size_t n;
  59      int delim;
  60      int extract_delim;
  61      int *eof;
  62 {
  63   char *ptr = buf;
  64   if (eof != NULL)
  65     *eof = 0;
  66   if (__builtin_expect (fp->_mode, -1) == 0)
  67     _IO_fwide (fp, -1);
  68   while (n != 0)
  69     {
  70       _IO_ssize_t len = fp->_IO_read_end - fp->_IO_read_ptr;
  71       if (len <= 0)
  72         {
  73           int c = __uflow (fp);
  74           if (c == EOF)
  75             {
  76               if (eof) *eof = c;
  77               break;
  78             }
  79           if (c == delim)
  80             {
  81               if (extract_delim > 0)
  82                 *ptr++ = c;
  83               else if (extract_delim < 0)
  84                 INTUSE(_IO_sputbackc) (fp, c);
  85               if (extract_delim > 0)
  86                 ++len;
  87               return ptr - buf;
  88             }
  89           *ptr++ = c;
  90           n--;
  91         }
  92         else
  93           {
  94             char *t;
  95             if ((_IO_size_t) len >= n)
  96               len = n;
  97             t = (char *) memchr ((void *) fp->_IO_read_ptr, delim, len);
  98             if (t != NULL)
  99               {
 100                 _IO_size_t old_len = ptr-buf;
 101                 len = t - fp->_IO_read_ptr;
 102                 if (extract_delim >= 0)
 103                   {
 104                     ++t;
 105                     if (extract_delim > 0)
 106                       ++len;
 107                   }
 108                 memcpy ((void *) ptr, (void *) fp->_IO_read_ptr, len);
 109                 fp->_IO_read_ptr = t;
 110                 return old_len + len;
 111               }
 112             memcpy ((void *) ptr, (void *) fp->_IO_read_ptr, len);
 113             fp->_IO_read_ptr += len;
 114             ptr += len;
 115             n -= len;
 116           }
 117     }
 118   return ptr - buf;
 119 }
 120 INTDEF(_IO_getline_info)
 121
 122 #endif /* Defined _LIBC || !_G_HAVE_IO_GETLINE_INFO */