9 files changed, 1376 insertions, 0 deletions

diff --git a/mixutils/.cvsignore b/mixutils/.cvsignore
new file mode 100644
index 0000000..349354d
--- /dev/null
+++ b/mixutils/.cvsignore
@@ -0,0 +1,6 @@
+.deps
+Makefile
+Makefile.in
+mixasm
+mixcmp
+mixvm
diff --git a/mixutils/Makefile.am b/mixutils/Makefile.am
new file mode 100644
index 0000000..710cc51
--- /dev/null
+++ b/mixutils/Makefile.am
@@ -0,0 +1,18 @@
+## Process this file with automake to produce Makefile.in
+
+# Copyright (C) 2000 jose antonio ortega ruiz <jaortega@retemail.es>
+#  
+# This file is free software; as a special exception the author gives
+# unlimited permission to copy and/or distribute it, with or without 
+# modifications, as long as this notice is preserved.
+# 
+# This program is distributed in the hope that it will be useful, but
+# WITHOUT ANY WARRANTY, to the extent permitted by law; without even the
+# implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+
+INCLUDES = -I$(includedir) 
+LDADD = $(top_builddir)/mixlib/libmix.a 
+
+bin_PROGRAMS = mixasm mixvm
+mixasm_SOURCES = mixasm.c mixasm_comp.h mixasm_comp.c
+mixvm_SOURCES = mixvm.c mixvm_loop.c mixvm_command.h mixvm_command.c
diff --git a/mixutils/mixasm.c b/mixutils/mixasm.c
new file mode 100644
index 0000000..935e5d1
--- /dev/null
+++ b/mixutils/mixasm.c
@@ -0,0 +1,126 @@
+/* -*-c-*- -------------- mixasm.c:
+ * Main function of mixasm, the mix assembler
+ * ------------------------------------------------------------------
+ * Copyright (C) 2000 jose antonio ortega ruiz <jaortega@acm.org>
+ *  
+ * 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 02111-1307, USA.
+ *  
+ */
+
+#include <mixlib/mix.h>
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <getopt.h>
+
+#include "mixasm_comp.h"
+
+enum {
+  VER_OPT = 'v',
+  HELP_OPT = 'h',
+  USAGE_OPT = 'u',
+  OUT_OPT =  'o',
+  LIST_OPT = 'l',
+  DEBUG_OPT = 'g'
+};
+
+
+static struct option long_options_[] =
+{
+  {"version", no_argument, 0, VER_OPT},
+  {"help", no_argument, 0, HELP_OPT},
+  {"usage", no_argument, 0, USAGE_OPT},
+  {"output", required_argument, 0, OUT_OPT},
+  {"list", optional_argument, 0, VER_OPT},
+  {"debug", no_argument, 0, DEBUG_OPT},
+  {0, 0, 0, 0}
+};
+
+static const gchar *USAGE_ = 
+N_("Usage: %s [-vhulg] [-o OUTPUT_FILE] [--version] [--help]\n"
+   "\t[--usage] [--debug] [--output=OUTPUT_FILE] [--list[=LIST_FILE]] file\n");
+
+     
+int
+main (int argc, char **argv)
+{
+  int c;
+  const char *prog_name = argv[0];
+  const char *src = NULL, *out = NULL, *list = NULL;
+  gboolean use_list = FALSE, debug = FALSE;
+
+  setlocale (LC_ALL, "");
+  bindtextdomain (PACKAGE, LOCALEDIR);
+  textdomain (PACKAGE);
+
+  while (1)
+    {
+      c = getopt_long (argc, argv, "vhuo:lg", long_options_, (int*)0);
+     
+      /* Detect the end of the options. */
+      if (c == -1)
+	break;
+     
+      switch (c)
+	{
+	case HELP_OPT: case USAGE_OPT:
+	  fprintf (stderr, _(USAGE_), prog_name);
+	  return EXIT_SUCCESS;
+     	case VER_OPT:
+	  fprintf (stderr, _("%s %s, MIX compiler.\n"), prog_name, VERSION);
+	  fprintf (stderr, MIX_GPL_LICENSE);
+	  return EXIT_SUCCESS;
+	case OUT_OPT:
+	  out = optarg;
+	  break;
+     	case LIST_OPT:
+	  use_list = TRUE;
+	  list = optarg;
+	  break;
+	case DEBUG_OPT:
+	  debug = TRUE;
+	  break;
+     	case '?':
+	  /* getopt already handles the output of a warning message */
+	  fprintf (stderr, _("(Try: %s -h)\n"), prog_name);
+	  return EXIT_FAILURE;
+	default:
+	  g_assert_not_reached ();
+	}
+    }
+   
+  if ( optind == argc )
+    {
+      fprintf (stderr, _("*** Error: Missing source file.\n"));
+      return EXIT_FAILURE;
+    }
+  if ( optind < argc-1 )
+    {
+      fprintf (stderr, _("*** Error: Too many input files.\n"));
+      return EXIT_FAILURE;
+    }
+  src = argv[optind];
+
+  
+  mix_init_lib ();
+  
+  c = mix_asm_compile (src, out, use_list, list, debug);
+
+  mix_release_lib ();
+  
+  return c;
+  
+}
+
diff --git a/mixutils/mixasm_comp.c b/mixutils/mixasm_comp.c
new file mode 100644
index 0000000..3a31363
--- /dev/null
+++ b/mixutils/mixasm_comp.c
@@ -0,0 +1,72 @@
+/* -*-c-*- -------------- mixasm_comp.c :
+ * Implementation of the functions declared in mixasm_comp.h
+ * ------------------------------------------------------------------
+ * Copyright (C) 2000 jose antonio ortega ruiz <jaortega@acm.org>
+ *  
+ * 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 02111-1307, USA.
+ *  
+ */
+
+#include <mixlib/mix.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <mixlib/mix_parser.h>
+#include "mixasm_comp.h"
+
+int
+mix_asm_compile(const gchar *src, const gchar *out, gboolean use_list,
+		const gchar *list, gboolean debug)
+{
+  int result = EXIT_SUCCESS;
+  mix_parser_t *parser;
+  mix_parser_err_t error;
+  
+  if ( (parser = mix_parser_new(src)) == NULL )
+    {
+      fprintf(stderr, _("*** Unable to open source file %s\n"), src);
+      return EXIT_FAILURE;
+    }
+  if ( mix_parser_compile(parser) == MIX_PERR_OK )
+    {
+      guint k;
+      if ( ( k = mix_parser_warning_count(parser) ) != 0 )
+	fprintf(stderr, _("(%d warning(s))\n"), k);
+      if ( (error = mix_parser_write_code(parser, out, debug)) != MIX_PERR_OK )
+	{
+	  fprintf(stderr, _("*** Error writing output code file: %s\n"),
+		  mix_parser_err_string(error));
+	  result = EXIT_FAILURE;
+	}
+      else if ( use_list 
+		&& (error = mix_parser_write_listing(parser, list)) != 
+		MIX_PERR_OK)
+	{
+	  fprintf(stderr, _("*** Error writing listing file: %s\n"),
+		  mix_parser_err_string(error));
+	  result = EXIT_FAILURE;
+	}
+    }
+  else
+    {
+      fprintf(stderr, _("(%d warning(s), %d error(s))\n"), 
+	      mix_parser_warning_count(parser), mix_parser_err_count(parser));
+      result = EXIT_FAILURE;
+    }
+  
+  mix_parser_delete(parser);
+  return result;
+}
+
+
diff --git a/mixutils/mixasm_comp.h b/mixutils/mixasm_comp.h
new file mode 100644
index 0000000..74c0474
--- /dev/null
+++ b/mixutils/mixasm_comp.h
@@ -0,0 +1,35 @@
+/* -*-c-*- ---------------- mixasm_comp.h :
+ * Declarations of functions used to compile mix source files.
+ * ------------------------------------------------------------------
+ * Copyright (C) 2000 jose antonio ortega ruiz <jaortega@acm.org>
+ *  
+ * 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 02111-1307, USA.
+ *  
+ */
+
+
+#ifndef MIXASM_COMP_H
+#define MIXASM_COMP_H
+
+#include <glib.h>
+
+extern int
+mix_asm_compile(const gchar *src, const gchar *out, gboolean use_list,
+		const gchar *list, gboolean debug);
+
+
+
+#endif /* MIXASM_COMP_H */
+
diff --git a/mixutils/mixvm.c b/mixutils/mixvm.c
new file mode 100644
index 0000000..207eca8
--- /dev/null
+++ b/mixutils/mixvm.c
@@ -0,0 +1,148 @@
+/* -*-c-*- -------------- mixvm.c :
+ * Main function for mixvm, the mix vm simulator
+ * ------------------------------------------------------------------
+ * Copyright (C) 2000 jose antonio ortega ruiz <jaortega@acm.org>
+ *  
+ * 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 02111-1307, USA.
+ *  
+ */
+
+
+
+#include <mixlib/mix.h>
+#include <mixlib/mix_vm.h>
+#include <mixlib/mix_vm_dump.h>
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <getopt.h>
+
+extern void
+mix_vmloop (const gchar *code_file);
+
+static void
+mix_vmrun (const gchar *code_file, gboolean dump);
+
+enum {
+  VER_OPT = 'v',
+  HELP_OPT = 'h',
+  USAGE_OPT = 'u',
+  RUN_OPT = 'r',
+  DUMP_OPT = 'd'
+};
+
+static const char *options_ = "vhurd";
+
+static struct option long_options_[] =
+{
+  {"version", no_argument, 0, VER_OPT},
+  {"help", no_argument, 0, HELP_OPT},
+  {"usage", no_argument, 0, USAGE_OPT},
+  {"run", required_argument, 0, RUN_OPT},
+  {"dump", no_argument, 0, DUMP_OPT},
+  {0, 0, 0, 0}
+};
+
+static const gchar *USAGE_ = 
+N_("Usage: %s [-vhurd] [--version] [--help] [--usage] [--run] [--dump] [MIX_FILE]\n");
+
+     
+int
+main (int argc, char **argv)
+{
+  int c;
+  const char *prog_name = argv[0];
+  const char *in = NULL;
+  gboolean run = FALSE;
+  gboolean dump = FALSE;
+      
+  setlocale (LC_ALL, "");
+  bindtextdomain (PACKAGE, LOCALEDIR);
+  textdomain (PACKAGE);
+
+  while (1)
+    {
+      c = getopt_long (argc, argv, options_, long_options_, (int*)0);
+     
+      /* Detect the end of the options. */
+      if (c == -1)
+	break;
+     
+      switch (c)
+	{
+	case HELP_OPT: case USAGE_OPT:
+	  fprintf (stderr, _(USAGE_), prog_name);
+	  return EXIT_SUCCESS;
+     	case VER_OPT:
+	  fprintf (stderr, _("%s %s, MIX Virtual Machine.\n"), 
+		   prog_name, VERSION);
+	  fprintf (stderr, MIX_GPL_LICENSE);
+	  return EXIT_SUCCESS;
+	case RUN_OPT:
+	  in = optarg;
+	  run = TRUE;
+	  break;
+	case DUMP_OPT:
+	  dump = TRUE;
+	  break;
+     	case '?':
+	  /* getopt already handles the output of a warning message */
+	  fprintf (stderr, _("(Try: %s -h)\n"), prog_name);
+	  return EXIT_FAILURE;
+	default:
+	  g_assert_not_reached ();
+	}
+    }
+   
+  if ( optind < argc-1 )
+    {
+      fprintf (stderr, _("*** Error: Too many input files.\n"));
+      return EXIT_FAILURE;
+    }
+  
+  if (!in)  in = argv[optind];
+  
+  mix_init_lib ();
+  
+  if (run) mix_vmrun(in, dump);
+  else mix_vmloop (in);
+
+  mix_release_lib ();
+  
+  return EXIT_SUCCESS;
+  
+}
+
+
+static void
+mix_vmrun (const gchar *code_file, gboolean dump) 
+{
+  mix_vm_t *vm = mix_vm_new ();
+  if (!mix_vm_load_file (vm, code_file)) {
+    fprintf (stderr, _("Error loading %s file\n"), code_file);
+    return;
+  }
+  mix_vm_run (vm);
+  if (dump) {
+    mix_dump_context_t *dc = mix_dump_context_new (MIX_DUMP_DEF_CHANNEL,
+						   0, 0,
+						   MIX_DUMP_ALL_NOMEM);
+    mix_vm_dump (vm, dc);
+    mix_dump_context_delete (dc);
+  }
+  mix_vm_delete (vm);
+}
+
+  
diff --git a/mixutils/mixvm_command.c b/mixutils/mixvm_command.c
new file mode 100644
index 0000000..e03dcfd
--- /dev/null
+++ b/mixutils/mixvm_command.c
@@ -0,0 +1,867 @@
+/* -*-c-*- -------------- mixvm_command.c :
+ * Implementation of the functions declared in mixvm_command.h
+ * ------------------------------------------------------------------
+ * Copyright (C) 2000 jose antonio ortega ruiz <jaortega@acm.org>
+ *  
+ * 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 02111-1307, USA.
+ *  
+ */
+
+
+#include <mixlib/mix.h>
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <ctype.h>
+#include <errno.h>
+#include <readline/readline.h>
+#include <readline/history.h>
+
+#include <mixlib/mix_vm.h>
+#include <mixlib/mix_vm_dump.h>
+#include "mixvm_command.h"
+
+/* The names of functions that actually do the manipulation. */
+#define DEC_FUN(name) \
+static int cmd_##name (char *arg)
+
+DEC_FUN (help_);
+DEC_FUN (shell_);
+DEC_FUN (load_);
+DEC_FUN (run_);
+DEC_FUN (next_);
+DEC_FUN (pc_);
+DEC_FUN (psym_);
+DEC_FUN (preg_);
+DEC_FUN (pflags_);
+DEC_FUN (pall_);
+DEC_FUN (pmem_);
+DEC_FUN (sreg_);
+DEC_FUN (scmp_);
+DEC_FUN (sover_);
+DEC_FUN (smem_);
+DEC_FUN (sbp_);
+DEC_FUN (sbpa_);
+DEC_FUN (cbp_);
+DEC_FUN (cbpa_);
+DEC_FUN (cabp_);
+DEC_FUN (compile_);
+DEC_FUN (edit_);
+DEC_FUN (quit_);
+
+/* A structure which contains information on the commands this program
+   can understand. */
+typedef struct {
+  const char *name;		/* User printable name of the function. */
+  Function *func;		/* Function to call to do the job. */
+  const char *doc;		/* Documentation for this function.  */
+  const char *usage;		/* Usage */
+} COMMAND;
+     
+COMMAND commands[] = {
+  { "help", cmd_help_, N_("Display this text"), "help [COMMAND]" },
+  { "?", cmd_help_, N_("Synonym for `help'"), "? [COMMAND]" },
+  { "!", cmd_shell_, N_("Execute shell command"), "! COMMAND" },
+  { "load", cmd_load_, N_("Load a MIX code file"), "load FILENAME" },
+  { "run", cmd_run_, N_("Run loaded or given MIX code file"), 
+    "run [FILENAME]" },
+  { "next", cmd_next_, N_("Execute next instruction(s)"), 
+    "next [NO_OF_INS]"},
+  { "pc", cmd_pc_, N_("Print program counter value"), "pc" },
+  { "psym", cmd_psym_, N_("Print symbol value"), "psym [SYMBOLNAME]" },
+  { "preg", cmd_preg_, N_("Print register value"), 
+    "preg [A | X | J | I[1-6]]" },
+  { "pflags", cmd_pflags_, N_("Print comparison and overflow flags"), 
+    "pflags" },
+  { "pall", cmd_pall_, N_("Print all registers and flags"), "pall" },
+  { "pmem", cmd_pmem_, N_("Print memory contents in address range"), 
+    "pmem FROM[-TO]" },
+  { "sreg", cmd_sreg_, N_("Set register value"), 
+    "preg A | X | J | I[1-6] VALUE" },
+  { "scmp", cmd_scmp_, N_("Set comparison flag value"), "scmp L | E | G" },
+  { "sover", cmd_sover_, N_("Set overflow flag value"), "sover T | F" },
+  { "smem", cmd_smem_, N_("Set memory contents in given address"), 
+    "smem ADDRESS VALUE" },
+  { "sbp", cmd_sbp_, N_("Set break point at given line"), "sbp LINENO" },
+  { "cbp", cmd_cbp_, N_("Clear break point at given line"), "cbp LINENO" },
+  { "sbpa", cmd_sbpa_, N_("Set break point at given address"),
+    "sbpa ADDRESS" },
+  { "cbpa", cmd_cbpa_, N_("Clear break point at given address"),
+    "cbpa ADDRESS" },
+  { "cabp", cmd_cabp_, N_("Clear all breakpoints"), "cabp" },
+  { "compile", cmd_compile_, N_("Compile a source file"), "compile FILENAME"},
+  { "edit", cmd_edit_, N_("Edit a source file"), "edit FILENAME"},
+  { "quit", cmd_quit_, N_("Quit the program"), "quit" },
+  { (char *)NULL, (Function *)NULL, (char *)NULL }
+};
+
+
+/* readline functions */
+static char *
+mixvm_cmd_generator_ (char *text, int state);
+
+
+/* Attempt to complete on the contents of TEXT.  START and END bound the
+   region of rl_line_buffer that contains the word to complete.  TEXT is
+   the word to complete.  We can use the entire contents of rl_line_buffer
+   in case we want to do some simple parsing.  Return the array of matches,
+   or NULL if there aren't any. */
+static char **
+mixvm_cmd_completion_ (char *text, int start, int end)
+{
+  char **matches;
+     
+  matches = (char **)NULL;
+     
+  /* If this word is at the start of the line, then it is a command
+     to complete.  Otherwise it is the name of a file in the current
+     directory. */
+  if (start == 0)
+    matches = completion_matches (text, mixvm_cmd_generator_);
+  
+  return (matches);
+}
+     
+/* Generator function for command completion.  STATE lets us know whether
+   to start from scratch; without any state (i.e. STATE == 0), then we
+   start at the top of the list. */
+static char *
+mixvm_cmd_generator_ (char *text, int state)
+{
+  static int list_index, len;
+  const char *name;
+     
+  /* If this is a new word to complete, initialize now.  This includes
+     saving the length of TEXT for efficiency, and initializing the index
+     variable to 0. */
+  if (!state)
+    {
+      list_index = 0;
+      len = strlen (text);
+    }
+     
+  /* Return the next name which partially matches from the command list. */
+  while ( (name = commands[list_index].name) != NULL)
+    {
+      list_index++;
+     
+      if (strncmp (name, text, len) == 0)
+	return (g_strdup (name));
+    }
+     
+  /* If no names matched, then return NULL. */
+  return ((char *)NULL);
+}
+
+
+/* command functions */
+static COMMAND *
+find_command_ (const char *name)
+{
+  int i;
+     
+  for (i = 0; commands[i].name; i++)
+    if (strcmp (name, commands[i].name) == 0)
+      return (&commands[i]);
+     
+  return ((COMMAND *)NULL);
+}
+
+
+/* the virtual machine and dump context */
+static mix_vm_t *vm_ = NULL;
+static mix_dump_context_t *dc_ = NULL;
+
+static int
+cmd_help_ (char *arg)
+{
+  static const int NO_OF_COLS = 6;
+  
+  int i;
+  int printed = 0;
+     
+  for (i = 0; commands[i].name; i++)
+    {
+      if (!*arg || (strcmp (arg, commands[i].name) == 0))
+	{
+	  printf (_("%s\t\t%s. Usage: %s\n"), commands[i].name, 
+		  _(commands[i].doc), commands[i].usage);
+	  printed++;
+	}
+    }
+     
+  if (!printed)
+    {
+      printf (_("No commands match `%s'.  Possibilities are:\n"), arg);
+     
+      for (i = 0; commands[i].name; i++)
+	{
+	  if (printed == NO_OF_COLS)
+	    {
+	      printed = 0;
+	      printf ("\n");
+	    }
+     
+	  printf ("%s\t", commands[i].name);
+	  printed++;
+	}
+     
+      if (printed)
+	printf ("\n");
+    }
+  return TRUE;
+}
+
+static int
+cmd_load_ (char *arg)
+{
+  errno = 0;
+  if (arg == NULL || *arg == '\0')
+    fputs (_("Missing file name\n"), stderr);
+  else if (!mix_vm_load_file (vm_, arg) )
+    {
+      fprintf (stderr, _("Cannot load %s: "), arg);
+      if ( errno == 0 )
+	fputs (_("Wrong file format\n"), stderr);
+      else
+	perror (NULL);
+      return TRUE + 1;
+    }
+  fprintf (stderr, _("Program loaded. Start address: %d\n"),
+	   mix_vm_get_prog_count (vm_));
+  
+  return TRUE;
+}
+
+static int
+cmd_run_ (char *arg)
+{
+  if (arg != NULL && *arg != '\0' && cmd_load_ (arg) != TRUE) 
+      return TRUE;
+  puts (_("Running ..."));
+  switch (mix_vm_run (vm_))
+    {
+    case MIX_VM_HALT:
+      puts (_("... done"));
+      break;
+    case MIX_VM_BREAK:
+      {
+	gulong line = mix_vm_get_break_lineno (vm_);
+	if (line != 0)
+	  printf (_("... stopped: breakpoint at line %ld (address %d)\n"), 
+		  line, mix_vm_get_prog_count (vm_));
+	else
+	  printf (_("... stopped: breakpoint at address %d\n"),
+		  mix_vm_get_prog_count (vm_));
+      }
+      break;
+    case MIX_VM_ERROR:
+      puts (_("... error executing loaded file"));
+      break;
+    default:
+      g_assert_not_reached ();
+      break;
+    }
+  return TRUE;
+}
+
+static int
+cmd_next_ (char *arg)
+{
+  int ins_no = 1;
+  if ( strlen (arg) != 0 )
+    {
+      int k = 0;
+      while (isdigit (arg[k]))
+	k++;
+      if (arg[k] != '\0')
+	{
+	  fprintf (stderr, _("Invalid argument: %s\n"), arg);
+	  return cmd_help_ ("next");
+	}
+      ins_no = atoi (arg);
+    }
+
+  while ( ins_no-- > 0 )
+    {
+      int k = mix_vm_exec_next (vm_);
+      if (k == MIX_VM_HALT)
+	{
+	  fprintf (stderr, _("End of program reached at address %d\n"),
+		   mix_vm_get_prog_count (vm_));
+	  break;
+	}
+      else if (k == MIX_VM_ERROR)
+	{
+	  fprintf (stderr, _("Error at address %d\n"),
+		   mix_vm_get_prog_count (vm_));
+	  break;
+	}
+    }
+
+  return TRUE;
+}
+
+static int
+cmd_quit_ (char *arg)
+{
+  puts ("Quitting ...");
+  if ( vm_ ) mix_vm_delete (vm_);
+  if ( dc_ ) mix_dump_context_delete (dc_);
+  return FALSE;
+}
+
+static int
+cmd_pc_ (char *arg)
+{
+  printf ("Current address: %d\n", mix_vm_get_prog_count (vm_));
+  return TRUE;
+}
+
+static int
+cmd_psym_ (char *arg)
+{
+  const mix_symbol_table_t *table = mix_vm_get_symbol_table (vm_);
+  if ( table == NULL )
+    fputs (_("Symbol table not available\n"), stderr);
+  else if (arg != NULL && *arg != '\0')
+    {
+      if ( mix_symbol_table_is_defined (table, arg) )
+	{
+	  mix_word_print (mix_symbol_table_value (table, arg), NULL);
+	  puts ("\n");
+	}
+      else
+	printf (_("%s: symbol not defined\n"), arg);
+    }
+  else
+    mix_symbol_table_print (table, MIX_SYM_ROWS, stdout);
+      
+  return TRUE;
+}
+
+static int
+cmd_preg_ (char *arg)
+{
+  mix_dump_context_set_opt (dc_, MIX_DUMP_NONE);
+  if ( strlen (arg) == 0 )
+    mix_dump_context_add_opt (dc_, MIX_DUMP_rALL);
+  else switch (*arg)
+    {
+    case 'A':
+      mix_dump_context_add_opt (dc_, MIX_DUMP_rA);
+      break;
+    case 'X':
+      mix_dump_context_add_opt (dc_, MIX_DUMP_rX);
+      break;
+    case 'J':
+      mix_dump_context_add_opt (dc_, MIX_DUMP_rJ);
+      break;
+    case 'I':
+      {
+	if ( strlen (arg) == 1 )
+	  mix_dump_context_add_opt (dc_, MIX_DUMP_rIa);
+	else
+	  {
+	    static gint32 opt[] = { MIX_DUMP_rI1, MIX_DUMP_rI2,
+				    MIX_DUMP_rI3, MIX_DUMP_rI4,
+				    MIX_DUMP_rI5, MIX_DUMP_rI6 
+	    };
+	    int i = arg[1] - '1';
+	    if ( i < 0 || i > 5 )
+	      {
+		fprintf (stderr, _("Invalid I index: %d"), i);
+		return TRUE;
+	      }
+	    mix_dump_context_add_opt (dc_, opt[i]);
+	  }
+      }
+      break;
+    default:
+      fprintf (stderr, _("Invalid argument: %s\n"), arg);
+      return TRUE;
+    }
+  mix_vm_dump (vm_, dc_);
+  return TRUE;
+}
+
+static int
+cmd_pflags_ (char *arg)
+{
+  mix_dump_context_set_opt (dc_, MIX_DUMP_CMP | MIX_DUMP_OVER);
+  mix_vm_dump (vm_, dc_);
+  return TRUE;
+}
+
+static int
+cmd_pall_ (char *arg)
+{
+  mix_dump_context_set_opt (dc_, MIX_DUMP_ALL_NOMEM);
+  mix_vm_dump (vm_, dc_);
+  return TRUE;
+}
+
+static int
+cmd_pmem_ (char *arg)
+{
+  glong begin = MIX_SHORT_ZERO, end = MIX_SHORT_ZERO;
+  int i = 0;
+  gboolean error = FALSE;
+  
+  if ( strlen (arg) == 0 )
+    {
+      fputs (_("Missing memory address\n"), stderr);
+      return TRUE;
+    }
+  while (isdigit (arg[i]))
+    i++;
+  while (isspace (arg[i]))
+    i++;
+  if (arg[i] == '\0')
+      begin = end = atol (arg);
+  else if (arg[i] == '-')
+    {
+      arg[i++] = '\0';
+      begin = atol (arg);
+      arg = arg + i;
+      i = 0;
+      while (isdigit (arg[i]))
+	i++;
+      while (isspace (arg[i]))
+	i++;
+      if (arg[i] != '\0') 
+	error = TRUE;
+      else 
+	end = atol (arg);
+    }
+  else
+    error = TRUE;
+  
+  if (error)
+    {
+      fprintf (stderr, _("Invalid argument: %s\n"), arg);
+      return cmd_help_("pmem");
+    }
+  if ( end < begin || end > MIX_VM_CELL_NO - 1 )
+    {
+      fprintf (stderr, _("Invalid range: %ld-%ld\n"), begin, end);
+      return TRUE;
+    }
+
+  mix_dump_context_set_opt (dc_, MIX_DUMP_CELLS);
+  mix_dump_context_range (dc_, mix_short_new (begin), mix_short_new (end + 1));
+  mix_vm_dump (vm_, dc_);
+  
+  return TRUE;
+}
+
+static int
+cmd_sreg_ (char *arg)
+{
+  int i = 0;
+  char reg = arg[0];
+  gboolean ok = TRUE;
+  long value;
+  
+  i = (reg == 'I') ? 2 : 1;
+  ok = strlen (arg) > 2 && isspace (arg[i]);
+  if (ok)
+    {
+      while (isspace (arg[i])) i++;
+      ok = isdigit (arg[i]) || arg[i] == '+' || arg[i] == '-';
+      if (ok)
+	{
+	  value = atol (arg + i);
+	  if (arg[i] == '+' || arg[i] == '-') i++;
+	  while (isdigit (arg[i])) i++;
+	  ok = (arg[i] == '\0');
+	  if (ok)
+	    switch (reg)
+	      {
+	      case 'A':
+		mix_vm_set_rA (vm_, mix_word_new (value));
+		break;
+	      case 'X':
+		mix_vm_set_rX (vm_, mix_word_new (value));
+		break;
+	      case 'J':
+		if ( value >= 0 )
+		  mix_vm_set_rJ (vm_, mix_short_new (value));
+		else
+		  ok = FALSE;
+		break;
+	      case 'I':
+		{
+		  guint k = arg[1] - '0';
+		  if ( k < 7 ) 
+		    mix_vm_set_rI (vm_, k, mix_short_new (value));
+		  else
+		    ok = FALSE;
+		}
+		break;
+	      default:
+		ok = FALSE;
+	      }
+	}
+    }
+  if (!ok)
+    {
+      fprintf (stderr, _("Invalid argument: %s\n"), arg);
+      cmd_help_ ("sreg");
+    }
+    
+  return TRUE;
+}
+
+static int
+cmd_scmp_ (char *arg)
+{
+  gboolean ok = (strlen (arg) == 1);
+  if (ok) switch (arg[0])
+    {
+    case 'L':
+      mix_vm_set_cmpflag (vm_, mix_LESS);
+      break;
+    case 'E':
+      mix_vm_set_cmpflag (vm_, mix_EQ);
+      break;
+    case 'G':
+      mix_vm_set_cmpflag (vm_, mix_GREAT);
+      break;
+    default:
+      ok = FALSE;
+    }
+  if (!ok)
+    {
+      fprintf (stderr, _("Invalid argument: %s\n"), arg);
+      cmd_help_ ("scmp");
+    }
+  
+  return TRUE;
+}
+
+static int
+cmd_sover_ (char *arg)
+{
+  gboolean ok = (strlen (arg) == 1);
+  if (ok) switch (arg[0])
+    {
+    case 'T':
+      mix_vm_set_overflow (vm_, TRUE);
+      break;
+    case 'F':
+      mix_vm_set_overflow (vm_, FALSE);
+      break;
+    default:
+      ok = FALSE;
+    }
+  if (!ok)
+    {
+      fprintf (stderr, _("Invalid argument: %s\n"), arg);
+      cmd_help_ ("sover");
+    }
+  
+  return TRUE;
+}
+
+static int
+cmd_smem_ (char *arg)
+{
+  gboolean ok = (strlen (arg) > 2 && isdigit (arg[0]));
+  gulong addr;
+  glong value;
+  int k = 0;
+  
+  if (ok)
+    {
+      while (isdigit (arg[k])) k++;
+      ok = isspace (arg[k]);
+      if (ok)
+	{
+	  arg[k++] = '\0';
+	  addr = atol (arg);
+	  ok = addr < MIX_VM_CELL_NO;
+	}
+      if (ok)
+	{
+	  while (isspace (arg[k])) k++;
+	  value = atol (arg + k);
+	  if ( arg[k] == '+' || arg[k] == '-' ) k++;
+	  while (isdigit (arg[k])) k++;
+	  ok = arg[k] == '\0';
+	}
+    }
+
+  if (ok)
+    mix_vm_set_addr_contents (vm_, mix_short_new (addr), mix_word_new (value));
+  else
+    {
+      fprintf (stderr, "Invalid argument: %s\n", arg);
+      cmd_help_ ("smem");
+    }
+  
+  return TRUE;
+}
+
+static int
+cmd_sbp_ (char *arg)
+{
+  glong lineno;
+  glong k = 0;
+  while (isdigit (arg[k])) k++;
+  if (arg[k] != '\0')
+    {
+      fprintf (stderr, _("Invalid argument: %s\n"), arg);
+      return cmd_help_ ("sbp");
+    }
+  lineno = atol (arg);
+  switch (k = mix_vm_set_breakpoint (vm_, lineno))
+    {
+    case MIX_VM_BP_INV_LINE:
+      fprintf (stderr, _("Line number %ld too high\n"), lineno);
+      break;
+    case MIX_VM_BP_ERROR:
+      fputs (_("Could not set breakpoint. Internal error\n"), stderr);
+      break;
+    case MIX_VM_BP_NDEBUG:
+      fputs (_("Could not set breakpoint. No debug info available\n"), stderr);
+      break;
+    default:
+      fprintf (stderr, _("Breakpoint set at line %ld\n"), k);
+      break;
+    }
+  return TRUE;
+}
+
+static int
+cmd_sbpa_ (char *arg)
+{
+  glong address;
+  glong k = 0;
+  while (isdigit (arg[k])) k++;
+  if (arg[k] != '\0')
+    {
+      fprintf (stderr, _("Invalid argument: %s\n"), arg);
+      return cmd_help_ ("sbpa");
+    }
+  address = atol (arg);
+  switch (mix_vm_set_breakpoint_address (vm_, address))
+    {
+    case MIX_VM_BP_INV_ADDRESS:
+      fprintf (stderr, _("Invalid address %ld\n"), address);
+      break;
+    case MIX_VM_BP_ERROR:
+      fputs (_("Could not set breakpoint. Internal error\n"), stderr);
+      break;
+    default:
+      fprintf (stderr, _("Breakpoint set at address %ld\n"), address);
+      break;
+    }
+  return TRUE;
+}
+
+static int
+cmd_cbp_ (char *arg)
+{
+  glong lineno;
+  int k = 0;
+  while (isdigit (arg[k])) k++;
+  if (arg[k] != '\0')
+    {
+      fprintf (stderr, _("Invalid argument: %s\n"), arg);
+      return cmd_help_ ("cbp");
+    }
+  lineno = atol (arg);
+  switch (mix_vm_clear_breakpoint (vm_, lineno))
+    {
+    case MIX_VM_BP_INV_LINE:
+      fprintf (stderr, _("No breakpoint set at line %ld\n"), lineno);
+      break;
+    case MIX_VM_BP_ERROR:
+      fputs (_("Could not set breakpoint. Internal error\n"), stderr);
+      break;
+    case MIX_VM_BP_NDEBUG:
+      fputs (_("No debug info available\n"), stderr);
+      break;
+    case MIX_VM_BP_OK:
+      fprintf (stderr, _("Breakpoint cleared at line %ld\n"), lineno);
+      break;
+    default:
+      g_assert_not_reached ();
+      break;
+    }
+  return TRUE;
+}
+
+static int
+cmd_cbpa_ (char *arg)
+{
+  glong address;
+  glong k = 0;
+  while (isdigit (arg[k])) k++;
+  if (arg[k] != '\0')
+    {
+      fprintf (stderr, _("Invalid argument: %s\n"), arg);
+      return cmd_help_ ("cbpa");
+    }
+  address = atol (arg);
+  switch (mix_vm_clear_breakpoint_address (vm_, address))
+    {
+    case MIX_VM_BP_INV_ADDRESS:
+      fprintf (stderr, _("Invalid address %ld\n"), address);
+      break;
+    case MIX_VM_BP_ERROR:
+      fputs (_("Could not clear breakpoint. Internal error\n"), stderr);
+      break;
+    default:
+      fprintf (stderr, _("Breakpoint cleared at address %ld\n"), address);
+      break;
+    }
+  return TRUE;
+}
+
+
+static int
+cmd_cabp_ (char *arg)
+{
+  if (strlen (arg) != 0)
+    {
+      fprintf (stderr, _("Invalid argument: %s\n"), arg);
+      return cmd_help_ ("cabp");
+    }
+  mix_vm_clear_all_breakpoints (vm_);
+  return TRUE;
+}
+
+static int 
+cmd_shell_ (char *arg)
+{
+  system (arg);
+  return TRUE;
+}
+
+static int
+cmd_compile_ (char *arg)
+{
+  gchar *line;
+  
+  if ( strlen (arg) == 0 )
+    return cmd_help_ ("compile");
+  
+  line = g_strconcat ("mixasm -g ", arg, NULL);
+  if ( system (line) == EXIT_SUCCESS )
+    fputs (_("Successful compilation\n"), stderr);
+  g_free (line);
+  
+  return TRUE;
+}
+
+static int
+cmd_edit_ (char *arg)
+{
+  static const gchar * envars[] = { "MDK_EDITOR", "X_EDITOR", "EDITOR",
+				    "VISUAL" 
+  };
+  static const guint s = sizeof (envars) / sizeof (envars[0]);
+  static const gchar *editor = NULL;
+  
+  if ( strlen (arg) == 0 )
+    return cmd_help_ ("edit");
+  
+  if (!editor)
+    {
+      int k;
+      for (k = 0; k < s; k++)
+	if ( (editor = getenv (envars[k])) != NULL ) break;
+    }
+  if (!editor)
+    {
+      int k;
+      fputs ("Cannot find editor (", stderr);
+      for (k = 0; k < s; k++)
+	fprintf (stderr, "%s ", envars[k]);
+      fputs ("undefined)\n", stderr);
+    }
+  else
+    {
+      gchar *line = g_strconcat (editor, " ", arg, NULL);
+      system (line);
+      g_free (line);
+    }
+  
+  return TRUE;
+}
+
+
+/* external interface */
+void
+mixvm_cmd_init (char *arg)
+{
+  /* Tell the completer that we want a crack first. */
+  rl_attempted_completion_function = (CPPFunction *)mixvm_cmd_completion_;
+  /* initialise the vm */
+  vm_ = mix_vm_new ();
+  dc_ = mix_dump_context_new (MIX_DUMP_DEF_CHANNEL, 
+			      MIX_SHORT_ZERO, MIX_SHORT_ZERO,
+			      MIX_DUMP_ALL);
+  if ( vm_ == NULL || dc_ == NULL )
+    g_error (_("Failed initialisation (no memory resources)"));
+  if (arg)
+    cmd_load_ (arg);
+}
+
+gboolean
+mixvm_cmd_exec (char *line)
+{
+  int i;
+  COMMAND *command;
+  char *word;
+
+  if (!line) return cmd_quit_(NULL);
+  
+  /* strip white  space */
+  line = g_strstrip(line);
+   
+  /* Isolate the command word. */
+  i = 0;
+  while (line[i] && isspace (line[i]))
+    i++;
+  word = line + i;
+     
+  while (line[i] && !isspace (line[i]))
+    i++;
+     
+  if (line[i])
+    line[i++] = '\0';
+     
+  command = find_command_ (word);
+     
+  if (!command)
+    {
+      fprintf (stderr, _("%s: No such command. Try \'help\'\n"), word);
+      return TRUE;
+    }
+     
+  /* Get argument to command, if any. */
+  while (isspace (line[i]))
+    i++;
+     
+  word = line + i;
+     
+  /* Call the function. */
+  return ((*(command->func)) (word));
+}
+     
+
diff --git a/mixutils/mixvm_command.h b/mixutils/mixvm_command.h
new file mode 100644
index 0000000..663aa41
--- /dev/null
+++ b/mixutils/mixvm_command.h
@@ -0,0 +1,38 @@
+/* -*-c-*- ---------------- mixvm_command.h :
+ * Declarations for commands accepted by the mix virtual machine
+ * ------------------------------------------------------------------
+ * Copyright (C) 2000 jose antonio ortega ruiz <jaortega@acm.org>
+ *  
+ * 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 02111-1307, USA.
+ *  
+ */
+
+
+#ifndef MIXVM_COMMAND_H
+#define MIXVM_COMMAND_H
+
+#include <glib.h>
+
+extern void
+mixvm_cmd_init (char *arg);
+
+extern gboolean
+mixvm_cmd_exec (char *line);
+
+
+
+
+#endif /* MIXVM_COMMAND_H */
+
diff --git a/mixutils/mixvm_loop.c b/mixutils/mixvm_loop.c
new file mode 100644
index 0000000..309c492
--- /dev/null
+++ b/mixutils/mixvm_loop.c
@@ -0,0 +1,66 @@
+/* -*-c-*- -------------- mixvm_loop.c :
+ * Implementation of mix vm command loop.
+ * ------------------------------------------------------------------
+ * Copyright (C) 2000 jose antonio ortega ruiz <jaortega@acm.org>
+ *  
+ * 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 02111-1307, USA.
+ *  
+ */
+
+
+
+#include <mixlib/mix.h>
+#include <stdio.h>
+#include <readline/readline.h>
+#include <readline/history.h>
+#include "mixvm_command.h"
+
+/* A static variable for holding the line. */
+static char *line_read = (char *)NULL;
+static const char *PROMPT = N_("MIX > ");
+
+/* Read a string, and return a pointer to it.  Returns NULL on EOF. */
+static char *
+rl_gets ()
+{
+  /* If the buffer has already been allocated, return the memory
+     to the free pool. */
+  if (line_read)
+    {
+      g_free (line_read);
+      line_read = (char *)NULL;
+    }
+     
+  /* Get a line from the user. */
+  line_read = readline ((char *)PROMPT);
+     
+  /* If the line has any text in it, save it on the history. */
+  if (line_read && *line_read)
+    add_history (line_read);
+     
+  return (line_read);
+}
+
+
+/* The main command loop of the virtual machine  */
+void
+mix_vmloop (const gchar *file)
+{
+  mixvm_cmd_init ((char *)file);
+  while ( mixvm_cmd_exec (rl_gets ()) ) 
+    ;
+}
+
+