Added Nitfol and Frotz source code.

[projects/chimara/chimara.git] / interpreters / nitfol / iff.c

diff --git a/interpreters/nitfol/iff.c b/interpreters/nitfol/iff.c
new file mode 100644 (file)
index 0000000..4fcfe41
--- /dev/null
+++ b/interpreters/nitfol/iff.c
@@ -0,0 +1,96 @@
+/*  Nitfol - z-machine interpreter using Glk for output.
+    Copyright (C) 1999  Evin Robertson
+
+    This program is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program; if not, write to the Free Software
+    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111, USA.
+
+    The author can be reached at nitfol@deja.com
+*/
+#include "nitfol.h"
+
+BOOL iffgetchunk(strid_t stream, char *desttype, glui32 *ulength,
+                glui32 file_size)
+{
+  int i;
+  glui32 c;
+  unsigned char length[4];
+
+  c = glk_stream_get_position(stream);
+  if(c & 1) {
+    glk_get_char_stream(stream);    /* Eat padding */
+    c++;
+  }
+
+  if(glk_get_buffer_stream(stream, desttype, 4) != 4)
+    return FALSE;
+  if(glk_get_buffer_stream(stream, (char *) length, 4) != 4)
+    return FALSE;
+
+  *ulength = MSBdecode4(length);
+
+  for(i = 0; i < 4; i++)
+    if(desttype[i] < 0x20 || desttype[i] > 0x7e)
+      return FALSE;
+
+  c += 8;
+
+  return ((c + *ulength) <= file_size);
+}
+
+
+BOOL ifffindchunk(strid_t stream, const char *type, glui32 *length, glui32 loc)
+{
+  char t[4];
+  glui32 file_size;
+
+  glk_stream_set_position(stream, 0, seekmode_End);
+  file_size = glk_stream_get_position(stream);
+
+  glk_stream_set_position(stream, loc, seekmode_Start);
+  *length = 0;
+  do {
+    glk_stream_set_position(stream, *length, seekmode_Current);
+    if(!iffgetchunk(stream, t, length, file_size))
+      return FALSE;
+   } while((t[0] != type[0]) || (t[1] != type[1]) ||
+          (t[2] != type[2]) || (t[3] != type[3]));
+
+  return TRUE;
+}
+
+
+void iffputchunk(strid_t stream, const char *type, glui32 ulength)
+{
+  glui32 c;
+  unsigned char length[4];
+
+  c = glk_stream_get_position(stream);
+  if(c & 1)
+    glk_put_char_stream(stream, 0);  /* Spew padding */
+
+  MSBencode4(length, ulength);
+
+  w_glk_put_buffer_stream(stream, type, 4);
+  w_glk_put_buffer_stream(stream, (char *) length, 4);
+}
+
+
+void iffpadend(strid_t stream)
+{
+  glui32 c;
+  
+  c = glk_stream_get_position(stream);
+  if(c & 1)
+    glk_put_char_stream(stream, 0);  /* Spew padding */
+}