libio/isgetline.cc

   1 /* This is part of libio/iostream, providing -*- C++ -*- input/output.
   2 Copyright (C) 1993 Free Software Foundation
   3
   4 This file is part of the GNU IO Library.  This library is free
   5 software; you can redistribute it and/or modify it under the
   6 terms of the GNU General Public License as published by the
   7 Free Software Foundation; either version 2, or (at your option)
   8 any later version.
   9
  10 This library is distributed in the hope that it will be useful,
  11 but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 GNU General Public License for more details.
  14
  15 You should have received a copy of the GNU General Public License
  16 along with this library; see the file COPYING.  If not, write to the Free
  17 Software Foundation, 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  18
  19 As a special exception, if you link this library with files
  20 compiled with a GNU compiler to produce an executable, this does not cause
  21 the resulting executable to be covered by the GNU General Public License.
  22 This exception does not however invalidate any other reasons why
  23 the executable file might be covered by the GNU General Public License. */
  24
  25 #include <libioP.h>
  26 #include "iostream.h"
  27 #include <string.h>
  28
  29 istream& istream::getline(char* buf, int len, char delim)
  30 {
  31   _gcount = 0;
  32   if (len <= 0)
  33     {
  34       set(ios::failbit);
  35       return *this;
  36     }
  37   int ch;
  38   if (ipfx1())
  39     {
  40       streambuf *sb = rdbuf();
  41       _gcount = _IO_getline_info(sb, buf, len - 1, delim, -1, &ch);
  42       if (ch != EOF)
  43         ch = sb->sbumpc();
  44       if (ch == EOF)
  45         set (_gcount == 0 ? (ios::failbit|ios::eofbit) : ios::eofbit);
  46       else if (ch != (unsigned char) delim)
  47         {
  48           set(ios::failbit);
  49           sb->sungetc(); // Leave delimiter unread.
  50         }
  51     }
  52   else
  53     ch = EOF;
  54   buf[_gcount] = '\0';
  55   if (ch == (unsigned char)delim)
  56     _gcount++; // The delimiter is counted in the gcount().
  57   return *this;
  58 }
  59
  60 istream& istream::get(char* buf, int len, char delim)
  61 {
  62   _gcount = 0;
  63   if (len <= 0)
  64     {
  65       set(ios::failbit);
  66       return *this;
  67     }
  68   if (ipfx1())
  69     {
  70       streambuf *sbuf = rdbuf();
  71       int ch;
  72       _gcount = _IO_getline_info(sbuf, buf, len - 1, delim, -1, &ch);
  73       if (_gcount == 0 && ch == EOF)
  74         set(ios::failbit|ios::eofbit);
  75     }
  76   buf[_gcount] = '\0';
  77   return *this;
  78 }
  79
  80
  81 // from Doug Schmidt
  82
  83 #define CHUNK_SIZE 512
  84
  85 /* Reads an arbitrarily long input line terminated by a user-specified
  86    TERMINATOR.  Super-nifty trick using recursion avoids unnecessary calls
  87    to NEW! */
  88
  89 char *_sb_readline (streambuf *sb, long& total, char terminator)
  90 {
  91     char buf[CHUNK_SIZE];
  92     char *ptr;
  93     int ch;
  94
  95     _IO_size_t count = _IO_getline_info(sb, buf, CHUNK_SIZE, terminator,
  96                                        -1, &ch);
  97     if (ch != EOF)
  98       ch = sb->sbumpc();
  99     long old_total = total;
 100     total += count;
 101     if (ch != EOF && ch != terminator) {
 102         total++; // Include ch in total.
 103         ptr = _sb_readline(sb, total, terminator);
 104         if (ptr) {
 105             memcpy(ptr + old_total, buf, count);
 106             ptr[old_total+count] = ch;
 107         }
 108         return ptr;
 109     }
 110
 111     ptr = new char[total+1];
 112     if (ptr != NULL) {
 113         ptr[total] = '\0';
 114         memcpy(ptr + total - count, buf, count);
 115     }
 116     return ptr;
 117 }
 118
 119 /* Reads an arbitrarily long input line terminated by TERMINATOR.
 120    This routine allocates its own memory, so the user should
 121    only supply the address of a (char *). */
 122
 123 istream& istream::gets(char **s, char delim /* = '\n' */)
 124 {
 125     if (ipfx1()) {
 126         long size = 0;
 127         streambuf *sb = rdbuf();
 128         *s = _sb_readline (sb, size, delim);
 129         _gcount = *s ? size : 0;
 130         if (sb->_flags & _IO_EOF_SEEN) {
 131             set(ios::eofbit);
 132             if (_gcount == 0)
 133                 set(ios::failbit);
 134         }
 135     }
 136     else {
 137         _gcount = 0;
 138         *s = NULL;
 139     }
 140     return *this;
 141 }