mix device operations handled via a vtable

1 files changed, 57 insertions, 111 deletions

diff --git a/mixlib/mix_device.c b/mixlib/mix_device.c
index 624702b..13e7150 100644
--- a/mixlib/mix_device.c
+++ b/mixlib/mix_device.c
@@ -1,7 +1,7 @@
 /* -*-c-*- -------------- mix_device.c :
  * Implementation of the functions declared in mix_device.h
  * ------------------------------------------------------------------
- * Copyright (C) 2000 Free Software Foundation, Inc.
+ * Copyright (C) 2000, 2001 Free Software Foundation, Inc.
  *  
  * 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
@@ -21,56 +21,14 @@
 
 
 #include "mix_file.h"
-#include "mix_device.h"
-
-/*
-  Actual definition of a mix device, which can be cast to
-  a mix file.
-*/
-struct mix_device_t 
-{
-  mix_iochannel_t *file;
-  mix_device_type_t type;
-};
-
-
-static const char *DEV_EXT_ = ".dev";
-
-static const char *DEF_NAMES_[] = {
-  "tape0", "tape1", "tape2", "tape3", "tape4", "tape5", "tape6", "tape7",
-  "disk0", "disk1", "disk2", "disk3", "disk4", "disk5", "disk6", "disk7",
-  "cardrd", "cardwr", "printer", "console", "paper"
-};
-
-static const size_t SIZES_[] = {
-  100, 100, 100, 100, 100, 100, 100, 100,
-  100, 100, 100, 100, 100, 100, 100, 100,
-  16, 16, 24, 14, 14
-};
-
-static const mix_device_mode_t MODES_[] = {
-  mix_dev_BIN, mix_dev_BIN, mix_dev_BIN, mix_dev_BIN, mix_dev_BIN,  
-  mix_dev_BIN, mix_dev_BIN, mix_dev_BIN, mix_dev_BIN, mix_dev_BIN,  
-  mix_dev_BIN, mix_dev_BIN, mix_dev_BIN, mix_dev_BIN, mix_dev_BIN,
-  mix_dev_BIN, mix_dev_CHAR, mix_dev_CHAR, mix_dev_CHAR, mix_dev_CHAR,
-  mix_dev_CHAR
-};
-
-static const mix_fmode_t FMODES_[] = {
-  mix_io_RDWRT,  mix_io_RDWRT,  mix_io_RDWRT,  mix_io_RDWRT,
-  mix_io_RDWRT,  mix_io_RDWRT,  mix_io_RDWRT,  mix_io_RDWRT,
-  mix_io_RDWRT,  mix_io_RDWRT,  mix_io_RDWRT,  mix_io_RDWRT,
-  mix_io_RDWRT,  mix_io_RDWRT,  mix_io_RDWRT,  mix_io_RDWRT,
-  mix_io_READ, mix_io_WRITE, mix_io_WRITE, mix_io_RDWRT, mix_io_WRITE
-};
-
-#define GET_CHANNEL_(dev) (dev->file)
-#define GET_FILE_(dev) ((mix_file_t *)(dev->file))
+#include "xmix_device.h"
 
 mix_device_t *
 mix_device_new (mix_device_type_t type)
 {
-  mix_device_t *result = g_new (mix_device_t, 1);
+  mix_device_t *result = NULL;
+  g_return_val_if_fail (type < mix_dev_INVALID, NULL);
+  result = g_new (mix_device_t, 1);
   result->type = type;
   if (type != mix_dev_CONSOLE) {
     result->file = MIX_IOCHANNEL(mix_file_new_with_def_ext (DEF_NAMES_[type],
@@ -78,26 +36,18 @@ mix_device_new (mix_device_type_t type)
 							    DEV_EXT_));
   } else
     result->file = mix_io_new (stdout);
-    
+  result->vtable = DEF_DEV_VTABLE_;
   return result;
 }
 
-void
-mix_device_delete (mix_device_t *dev)
-{
-  if (dev != NULL)
-    {
-      if (dev->type != mix_dev_CONSOLE && GET_FILE_(dev) != NULL)
-	mix_file_delete (GET_FILE_(dev));
-      g_free (dev);
-    }
-}
+
 
 mix_device_t *
 mix_device_new_with_name (mix_device_type_t type, const gchar *name)
 {
   mix_device_t *result = NULL;
-  g_return_val_if_fail (name != NULL, result);
+  g_return_val_if_fail (name != NULL, NULL);
+  g_return_val_if_fail (type < mix_dev_INVALID, NULL);
   result = g_new (mix_device_t, 1);  
   result->type = type;
   if (type != mix_dev_CONSOLE)
@@ -110,11 +60,46 @@ mix_device_new_with_name (mix_device_type_t type, const gchar *name)
     {
       result->file = mix_io_new (stdout);
     }
+  result->vtable = DEF_DEV_VTABLE_;
   return result;
 }
 
+/*
+  Create a new device with a given type and stream
+*/
+mix_device_t *
+mix_device_new_with_file (mix_device_type_t type, FILE *file)
+{
+  mix_device_t *result = NULL;
+  g_return_val_if_fail (file != NULL, NULL);
+  g_return_val_if_fail (type < mix_dev_INVALID, NULL);
+  result = g_new (mix_device_t, 1);
+  result->type = type;
+  result->file = mix_io_new (file);
+  result->vtable = DEF_DEV_VTABLE_;
+  return result;
+}
+
+void
+mix_device_delete (mix_device_t *dev)
+{
+  if (dev != NULL)
+    {
+      if (dev->type != mix_dev_CONSOLE && GET_FILE_(dev) != NULL)
+	mix_file_delete (GET_FILE_(dev));
+      g_free (dev);
+    }
+}
+
+mix_device_type_t
+mix_device_type (const mix_device_t *dev)
+{
+  g_return_val_if_fail (dev != NULL, mix_dev_INVALID);
+  return dev->type;
+}
+
 const char *
-mix_device_get_name (mix_device_t *dev)
+mix_device_get_name (const mix_device_t *dev)
 {
   g_return_val_if_fail (dev != NULL, NULL);
   return mix_file_base_name(GET_FILE_(dev));
@@ -124,7 +109,7 @@ mix_device_get_name (mix_device_t *dev)
   Get the device block size
 */
 size_t
-mix_device_block_size (mix_device_t *dev)
+mix_device_block_size (const mix_device_t *dev)
 {
   g_return_val_if_fail (dev != NULL, 0);
   return SIZES_[dev->type];
@@ -134,7 +119,7 @@ mix_device_block_size (mix_device_t *dev)
   Get the device io mode
 */
 mix_device_mode_t
-mix_device_mode (mix_device_t *dev) 
+mix_device_mode (const mix_device_t *dev) 
 {
   g_return_val_if_fail (dev != NULL, 0);
   return MODES_[dev->type];
@@ -146,23 +131,10 @@ mix_device_mode (mix_device_t *dev)
 gboolean
 mix_device_write (mix_device_t *dev, const mix_word_t *block) 
 {
-  gboolean result;
-  
   g_return_val_if_fail (dev != NULL, FALSE);
   g_return_val_if_fail (block != NULL, FALSE);
-  if (FMODES_[dev->type] == mix_io_READ) return FALSE;
-  if (MODES_[dev->type] == mix_dev_CHAR)
-    result = mix_io_write_word_array_as_char (GET_CHANNEL_ (dev),
-					      block, SIZES_[dev->type]);
-  else
-    result = mix_io_write_word_array (GET_CHANNEL_ (dev),
-				      block, SIZES_[dev->type]);
-  if (result && mix_device_mode(dev) == mix_dev_CHAR) 
-    putc ('\n', mix_io_to_FILE (GET_CHANNEL_ (dev)));
-
-  fflush (mix_io_to_FILE (GET_CHANNEL_ (dev)));
-  
-  return result;
+  g_assert (dev->vtable != NULL);
+  return (dev->vtable->write) (dev, block);
 }
 
 gboolean
@@ -170,48 +142,22 @@ mix_device_read (mix_device_t *dev, mix_word_t *block)
 {
   g_return_val_if_fail (dev != NULL, FALSE);
   g_return_val_if_fail (block != NULL, FALSE);
-  if (FMODES_[dev->type] == mix_io_WRITE) return FALSE;
-  if (MODES_[dev->type] == mix_dev_CHAR)
-    return mix_io_read_word_array_as_char (GET_CHANNEL_ (dev),
-					   block, SIZES_[dev->type]);
-  else
-    return mix_io_read_word_array (GET_CHANNEL_ (dev),
-				   block, SIZES_[dev->type]);
+  g_assert (dev->vtable != NULL);
+  return (dev->vtable->read) (dev, block);
 }
 
 gboolean
 mix_device_ioc (mix_device_t *dev, mix_short_t arg) 
 {
-  int m;
-  FILE *file;
-  
   g_return_val_if_fail (dev != NULL, FALSE);
-
-  m = mix_short_magnitude(arg);
-  if (mix_short_is_negative(arg)) m = -m;
-  m *= sizeof (mix_word_t) * SIZES_[dev->type];
-  file = mix_io_to_FILE (GET_CHANNEL_(dev));
-  
-  if (dev->type >= mix_dev_TAPE_0 && dev->type <= mix_dev_TAPE_7)
-    {
-      if (m == 0) rewind (file);
-      else fseek (file, m, SEEK_CUR);
-    }
-  if (dev->type >= mix_dev_DISK_0 && dev->type <= mix_dev_DISK_7)
-    {
-      g_return_val_if_fail (m == 0, FALSE);
-      // position disk
-    }
-  if (dev->type == mix_dev_PAPER_TAPE)
-    {
-      g_return_val_if_fail (m == 0, FALSE);
-      rewind (file);
-    }
-  return TRUE;
+  g_assert (dev->vtable != NULL);
+  return (dev->vtable->ioc) (dev, arg);
 }
 
 gboolean
-mix_device_busy (mix_device_t *dev)
+mix_device_busy (const mix_device_t *dev)
 {
-  return (dev != NULL && !mix_io_is_ready(GET_CHANNEL_(dev)));
+  g_return_val_if_fail (dev != NULL, FALSE);
+  return (dev->vtable->busy) (dev);
+
 }