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(sb, buf, len - 1, delim, -1);
  42       ch = sb->sbumpc();
  43       if (ch == EOF)
  44         set (_gcount == 0 ? (ios::failbit|ios::eofbit) : ios::eofbit);
  45       else if (ch != (unsigned char) delim)
  46         {
  47           set(ios::failbit);
  48           sb->sungetc(); // Leave delimiter unread.
  49         }
  50     }
  51   else
  52     ch = EOF;
  53   buf[_gcount] = '\0';
  54   if (ch == (unsigned char)delim)
  55     _gcount++; // The delimiter is counted in the gcount().
  56   return *this;
  57 }
  58
  59 istream& istream::get(char* buf, int len, char delim)
  60 {
  61   _gcount = 0;
  62   if (len <= 0)
  63     {
  64       set(ios::failbit);
  65       return *this;
  66     }
  67   if (ipfx1())
  68     {
  69       streambuf *sbuf = rdbuf();
  70       long count = _IO_getline(sbuf, buf, len - 1, delim, -1);
  71       if (count == 0 && sbuf->sgetc() == EOF)
  72         set(ios::failbit|ios::eofbit);
  73       else
  74         _gcount = count;
  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(sb, buf, CHUNK_SIZE, terminator, -1);
  96     ch = sb->sbumpc();
  97     long old_total = total;
  98     total += count;
  99     if (ch != EOF && ch != terminator) {
 100         total++; // Include ch in total.
 101         ptr = _sb_readline(sb, total, terminator);
 102         if (ptr) {
 103             memcpy(ptr + old_total, buf, count);
 104             ptr[old_total+count] = ch;
 105         }
 106         return ptr;
 107     }
 108
 109     ptr = new char[total+1];
 110     if (ptr != NULL) {
 111         ptr[total] = '\0';
 112         memcpy(ptr + total - count, buf, count);
 113     }
 114     return ptr;
 115 }
 116
 117 /* Reads an arbitrarily long input line terminated by TERMINATOR.
 118    This routine allocates its own memory, so the user should
 119    only supply the address of a (char *). */
 120
 121 istream& istream::gets(char **s, char delim /* = '\n' */)
 122 {
 123     if (ipfx1()) {
 124         long size = 0;
 125         streambuf *sb = rdbuf();
 126         *s = _sb_readline (sb, size, delim);
 127         _gcount = *s ? size : 0;
 128         if (sb->_flags & _IO_EOF_SEEN) {
 129             set(ios::eofbit);
 130             if (_gcount == 0)
 131                 set(ios::failbit);
 132         }
 133     }
 134     else {
 135         _gcount = 0;
 136         *s = NULL;
 137     }
 138     return *this;
 139 }