reactos/lib/kjs/ksrc/iostream.c

   1 /*
   2  * I/O streams.
   3  * Copyright (c) 1998 New Generation Software (NGS) Oy
   4  *
   5  * Author: Markku Rossi <mtr@ngs.fi>
   6  */
   7
   8 /*
   9  * This library is free software; you can redistribute it and/or
  10  * modify it under the terms of the GNU Library General Public
  11  * License as published by the Free Software Foundation; either
  12  * version 2 of the License, or (at your option) any later version.
  13  *
  14  * This library is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  17  * Library General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU Library General Public
  20  * License along with this library; if not, write to the Free
  21  * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
  22  * MA 02111-1307, USA
  23  */
  24
  25 /*
  26  * $Source: /cygdrive/c/RCVS/CVS/ReactOS/reactos/lib/kjs/ksrc/iostream.c,v $
  27  * $Id$
  28  */
  29
  30 #include "jsint.h"
  31
  32 /*
  33  * Types and definitions.
  34  */
  35
  36 #define DEFAULT_BUFFER_SIZE 4096
  37
  38 /*
  39  * Global functions.
  40  */
  41
  42 JSIOStream *
  43 js_iostream_new ()
  44 {
  45   JSIOStream *stream;
  46
  47   stream = js_calloc (NULL, 1, sizeof (*stream));
  48   if (stream == NULL)
  49     return NULL;
  50
  51   stream->buflen = DEFAULT_BUFFER_SIZE;
  52   stream->buffer = js_malloc (NULL, stream->buflen);
  53   if (stream->buffer == NULL)
  54     {
  55       js_free (stream);
  56       return NULL;
  57     }
  58
  59   return stream;
  60 }
  61
  62 size_t
  63 js_iostream_read (JSIOStream *stream, void *ptr, size_t size)
  64 {
  65   size_t total = 0;
  66   int got;
  67
  68   if (stream->writep)
  69     {
  70       /* We have buffered output data. */
  71       if (js_iostream_flush (stream) == EOF)
  72         return 0;
  73
  74       assert (stream->writep == 0);
  75     }
  76
  77   while (size > 0)
  78     {
  79       /* First, take everything from the buffer. */
  80       if (stream->bufpos < stream->data_in_buf)
  81         {
  82           got = stream->data_in_buf - stream->bufpos;
  83
  84           if (size < got)
  85             got = size;
  86
  87           memcpy (ptr, stream->buffer + stream->bufpos, got);
  88
  89           stream->bufpos += got;
  90           size -= got;
  91           ptr = (void *)((unsigned char *)ptr + got);
  92           total += got;
  93         }
  94       else
  95         {
  96           if (stream->at_eof)
  97             /* EOF seen, can't read more. */
  98             break;
  99
 100           js_iostream_fill_buffer (stream);
 101         }
 102     }
 103
 104   return total;
 105 }
 106
 107
 108 size_t
 109 js_iostream_write (JSIOStream *stream, void *ptr, size_t size)
 110 {
 111   int i;
 112
 113   for( i = 0; size > i; i++ )
 114     DbgPrint("%c", ((char *)ptr)[i]);
 115
 116   return i;
 117 }
 118
 119
 120 int
 121 js_iostream_flush (JSIOStream *stream)
 122 {
 123   return 0;
 124 }
 125
 126 int
 127 js_iostream_unget (JSIOStream *stream, int byte)
 128 {
 129   return 0;
 130 }
 131
 132 int
 133 js_iostream_close (JSIOStream *stream)
 134 {
 135   int result = 0;
 136
 137   if (stream == NULL)
 138     return result;
 139
 140   if (js_iostream_flush (stream) == EOF)
 141     result = EOF;
 142
 143   if (stream->close)
 144     (*stream->close) (stream->context);
 145
 146   js_free (stream->buffer);
 147   js_free (stream);
 148
 149   return result;
 150 }
 151
 152
 153 int
 154 js_iostream_seek (JSIOStream *stream, long offset, int whence)
 155 {
 156   int result;
 157
 158   if (js_iostream_flush (stream) == EOF)
 159     return -1;
 160
 161   result = (*stream->seek) (stream->context, offset, whence);
 162   if (result == 0)
 163     /* Successful.  Clear the eof flag. */
 164     stream->at_eof = 0;
 165
 166   return result;
 167 }
 168
 169
 170 long
 171 js_iostream_get_position (JSIOStream *stream)
 172 {
 173   long pos;
 174
 175   /* Flush the possible buffered output. */
 176   if (js_iostream_flush (stream) == EOF)
 177     return -1;
 178
 179   pos = (*stream->get_position) (stream->context);
 180   if (pos < 0)
 181     return pos;
 182
 183   /*
 184    * The logical position if at <bufpos>, the context's idea is at
 185    * <data_in_buf>.  Adjust.
 186    */
 187   return pos - (stream->data_in_buf - stream->bufpos);
 188 }
 189
 190
 191 long
 192 js_iostream_get_length (JSIOStream *stream)
 193 {
 194   /* Flush the possible buffered output. */
 195   if (js_iostream_flush (stream) == EOF)
 196     return -1;
 197
 198   return (*stream->get_length) (stream->context);
 199 }
 200
 201
 202 void
 203 js_iostream_fill_buffer (JSIOStream *stream)
 204 {
 205   if (stream->read == NULL)
 206     {
 207       stream->at_eof = 1;
 208       return;
 209     }
 210
 211   stream->data_in_buf = (*stream->read) (stream->context, stream->buffer,
 212                                          stream->buflen, &stream->error);
 213   stream->bufpos = 0;
 214   if (stream->data_in_buf == 0)
 215     stream->at_eof = 1;
 216 }