Patch rtems-4.5-beta3-mon.diff from Chris Johns <cjohns@cybertec.com.au>

to:

I have also added the ability to register and unregister commands. This
allows me to create a set of monitor commands for the network stack plus
basic memory dump/patch commands (needs a working probe interface). I
will also look at a basic ls/cd/rm/mv/cp command set at some stage.

I have been thinking about changing the monitor in the future to more
like a light weight RTEMS shell, `eshell' for embedded shell. This is a
story for another day but is a process or getting the commands to map to
the filesystem (eg, major=commands, minor=command) and supporting an
environment. The filesystem provide a structure for the commands.

3 files changed, 761 insertions, 174 deletions

diff --git a/c/src/libmisc/monitor/mon-command.c b/c/src/libmisc/monitor/mon-command.c
index 5c733b60d9..cf25325880 100644
--- a/c/src/libmisc/monitor/mon-command.c
+++ b/c/src/libmisc/monitor/mon-command.c
@@ -14,9 +14,420 @@
 #include <string.h>
 
 /*
+ * CCJ: 26-3-2000, adding command history and command line
+ * editing. This code is donated from My Right Boot and not
+ * covered by GPL, only the RTEMS license.
+ */
+
+/*
+ * Some key labels to define special keys.
+ */
+
+#define KEYS_EXTENDED    (0x8000)
+#define KEYS_NORMAL_MASK (0x00ff)
+#define KEYS_INS         (0)
+#define KEYS_DEL         (1)
+#define KEYS_UARROW      (2)
+#define KEYS_DARROW      (3)
+#define KEYS_LARROW      (4)
+#define KEYS_RARROW      (5)
+#define KEYS_HOME        (6)
+#define KEYS_END         (7) 
+#define KEYS_F1          (8) 
+#define KEYS_F2          (9) 
+#define KEYS_F3          (10)
+#define KEYS_F4          (11)
+#define KEYS_F5          (12)
+#define KEYS_F6          (13)
+#define KEYS_F7          (14)
+#define KEYS_F8          (15)
+#define KEYS_F9          (16)
+#define KEYS_F10         (17)
+
+#define RTEMS_COMMAND_BUFFER_SIZE (75)
+
+static char monitor_prompt[32];
+static char buffer[RTEMS_COMMAND_BUFFER_SIZE];
+static int  pos;
+static int  logged_in;
+
+/*
+ * History data.
+ */
+
+#define RTEMS_COMMAND_HISTORIES (20)
+
+static char history_buffer[RTEMS_COMMAND_HISTORIES][RTEMS_COMMAND_BUFFER_SIZE];
+static int  history_pos[RTEMS_COMMAND_HISTORIES];
+static int  history;
+static int  history_next;
+
+/*
+ * Translation tables. Not sure if this is the best way to
+ * handle this, how-ever I wish to avoid the overhead of
+ * including a more complete and standard environment such
+ * as ncurses.
+ */
+
+struct translation_table
+{
+  char                     expecting;
+  struct translation_table *branch;
+  unsigned int             key;
+};
+
+static struct translation_table trans_two[] =
+{
+  { '~', 0, KEYS_INS },
+  { 0,   0, 0 }
+};
+
+static struct translation_table trans_three[] =
+{
+  { '~', 0, KEYS_DEL },
+  { 0,   0, 0 }
+};
+
+static struct translation_table trans_tab_csi[] =
+{
+  { '2', trans_two,   0 },
+  { '3', trans_three, 0 },
+  { 'A', 0,           KEYS_UARROW },
+  { 'B', 0,           KEYS_DARROW },
+  { 'D', 0,           KEYS_LARROW },
+  { 'C', 0,           KEYS_RARROW },
+  { 'F', 0,           KEYS_END },
+  { 'H', 0,           KEYS_HOME },
+  { 0,   0,           0 }
+};
+
+static struct translation_table trans_tab_O[] =
+{
+  { '1', 0, KEYS_F1 },
+  { '2', 0, KEYS_F2 },
+  { '3', 0, KEYS_F3 },
+  { '4', 0, KEYS_F4 },
+  { '5', 0, KEYS_F5 },
+  { '6', 0, KEYS_F6 },
+  { '7', 0, KEYS_F7 },
+  { '8', 0, KEYS_F8 },
+  { '9', 0, KEYS_F9 },
+  { ':', 0, KEYS_F10 },
+  { 'P', 0, KEYS_F1 },
+  { 'Q', 0, KEYS_F2 },
+  { 'R', 0, KEYS_F3 },
+  { 'S', 0, KEYS_F4 },
+  { 'T', 0, KEYS_F5 },
+  { 'U', 0, KEYS_F6 },
+  { 'V', 0, KEYS_F7 },
+  { 'W', 0, KEYS_F8 },
+  { 'X', 0, KEYS_F9 },
+  { 'Y', 0, KEYS_F10 },
+  { 0,   0, 0 }
+};
+
+static struct translation_table trans_tab[] =
+{
+  { '[', trans_tab_csi, 0 },    /* CSI command sequences */
+  { 'O', trans_tab_O,   0 },    /* O are the fuction keys */
+  { 0,   0,             0 }
+};
+
+/*
+ * Perform a basic tranlation for some ANSI/VT100 key codes.
+ * This code could do with a timeout on the ESC as it is
+ * now lost from the input stream. It is not* used by the
+ * line editor below so considiered not worth the effort.
+ */
+
+static unsigned int
+rtems_monitor_getchar (
+)
+{
+  struct translation_table *translation = 0;
+  for (;;)
+  {
+    char c = getchar ();
+    if (c == 27)
+      translation = trans_tab;
+    else
+    {
+      /*
+       * If no translation happing just pass through
+       * and return the key.
+       */
+      if (translation)
+      {
+        /*
+         * Scan the current table for the key, and if found
+         * see if this key is a fork. If so follow it and
+         * wait else return the extended key.
+         */
+        int index    = 0;
+        int branched = 0;
+        while ((translation[index].expecting != '\0') ||
+               (translation[index].key != '\0'))
+        {
+          if (translation[index].expecting == c)
+          {
+            /*
+             * A branch is take if more keys are to come.
+             */
+            if (translation[index].branch == 0)
+              return KEYS_EXTENDED | translation[index].key;
+            else
+            {
+              translation = translation[index].branch;
+              branched    = 1;
+              break;
+            }
+          }
+          index++;
+        }
+        /*
+         * Who knows what these keys are, just drop them.
+         */
+        if (!branched)
+          translation = 0;
+      }
+      else
+        return c;
+    }
+  }
+}
+
+/*
+ * The line editor with history.
+ */
+
+static int
+rtems_monitor_line_editor (
+    char *command
+)
+{
+  int repeating = 0;
+
+  memset (buffer, 0, RTEMS_COMMAND_BUFFER_SIZE);
+  history = history_next;
+  pos     = 0;
+          
+  if (!logged_in)
+    printf ("\nMonitor ready, press enter to login.\n\n");
+  else
+    printf ("%s $ ", monitor_prompt);
+
+  while (1)
+  {
+    unsigned int extended_key = rtems_monitor_getchar ();
+    char         c = extended_key & KEYS_NORMAL_MASK;
+
+    /*
+     * Make the extended_key usable as a boolean.
+     */
+    extended_key &= ~KEYS_NORMAL_MASK;
+    
+    if (!extended_key && !logged_in)
+    {
+      if (c == '\n')
+      {
+        logged_in = 1;
+        /*
+         * The prompt has changed from `>' to `$' to help know
+         * which version of the monitor code people are using.
+         */
+        printf("%s $ ", monitor_prompt);
+      }
+    }
+    else
+    {
+      if (extended_key)
+      {
+        switch (c)
+        {
+          case KEYS_END:
+            printf (buffer + pos);
+            pos = (int) strlen (buffer);
+            break;
+
+          case KEYS_HOME:
+            printf ("\r%s $ ", monitor_prompt);
+            pos = 0;
+            break;
+        
+          case KEYS_LARROW:
+            if (pos > 0)
+            {
+              pos--;
+              putchar ('\b');
+            }
+            break;
+
+          case KEYS_RARROW:
+            if ((pos < RTEMS_COMMAND_BUFFER_SIZE) && (buffer[pos] != '\0'))
+            {
+              putchar (buffer[pos]);
+              pos++;
+            }
+            break;
+
+          case KEYS_UARROW:
+            /*
+             * If we are moving up the histories then we need to save the working
+             * buffer.
+             */
+            if (history)
+            {
+              int end;
+              int bs;
+              if (history == history_next)
+              {
+                memcpy (history_buffer[history_next], buffer,
+                        RTEMS_COMMAND_BUFFER_SIZE);
+                history_pos[history_next] = pos;
+              }
+              history--;
+              memcpy (buffer, history_buffer[history],
+                      RTEMS_COMMAND_BUFFER_SIZE);
+              pos = history_pos[history];
+              printf ("\r%*c", RTEMS_COMMAND_BUFFER_SIZE, ' ');
+              printf ("\r%s $ %s", monitor_prompt, buffer);
+              end = (int) strlen (buffer);
+              for (bs = 0; bs < (end - pos); bs++)
+                putchar ('\b');
+            }
+            break;
+                  
+          case KEYS_DARROW:
+            if (history < history_next)
+            {
+              int end;
+              int bs;
+              history++;
+              memcpy (buffer, history_buffer[history],
+                      RTEMS_COMMAND_BUFFER_SIZE);
+              pos = history_pos[history];
+              printf ("\r%*c", RTEMS_COMMAND_BUFFER_SIZE, ' ');
+              printf ("\r%s $ %s", monitor_prompt, buffer);
+              end = (int) strlen (buffer);
+              for (bs = 0; bs < (end - pos); bs++)
+                putchar ('\b');
+            }
+            break;
+
+          case KEYS_DEL:
+            if (buffer[pos] != '\0')
+            {
+              int end;
+              int bs;
+              strcpy (&buffer[pos], &buffer[pos + 1]);
+              printf ("\r%s $ %s", monitor_prompt, buffer);
+              end = (int) strlen (buffer);
+              for (bs = 0; bs < (end - pos); bs++)
+                putchar ('\b');
+            }
+            break;
+        }
+      }
+      else
+      {
+        switch (c)
+        {
+          case '\b':
+          case '\x7e':
+          case '\x7f':
+            if (pos > 0)
+            {
+              int bs;
+              pos--;
+              strcpy (buffer + pos, buffer + pos + 1);
+              printf ("\b%s \b", buffer + pos);
+              for (bs = 0; bs < ((int) strlen (buffer) - pos); bs++)
+                putchar ('\b');
+            }
+            break;
+
+          case '\n':
+            /*
+             * Process the command.
+             */
+            printf ("\n");
+            repeating = 1;
+            /*
+             * Only process the history if we have a command and
+             *a history.
+             */
+            if (strlen (buffer))
+            {
+              if (history_next && (history == history_next))
+              {
+                /*
+                 * Do not place the last command into the history
+                 *if the same.
+                 */
+                if (strcmp (history_buffer[history_next - 1], buffer))
+                  repeating = 0;
+              }
+              else
+                repeating = 0;
+            }
+            if (!repeating)
+            {
+              memcpy (history_buffer[history_next], buffer,
+                      RTEMS_COMMAND_BUFFER_SIZE);
+              history_pos[history_next] = pos;
+              if (history_next < (RTEMS_COMMAND_HISTORIES - 1))
+                history_next++;
+              else
+              {
+                memmove (history_buffer[0], history_buffer[1],
+                         RTEMS_COMMAND_BUFFER_SIZE * (RTEMS_COMMAND_HISTORIES - 1));
+                memmove (&history_pos[0], &history_pos[1],
+                         sizeof (history_pos[0]) * (RTEMS_COMMAND_HISTORIES - 1));
+              }
+            }
+            else
+            {
+              if (history_next)
+                memcpy (buffer, history_buffer[history_next - 1],
+                        RTEMS_COMMAND_BUFFER_SIZE);
+            }
+            memmove (command, buffer, RTEMS_COMMAND_BUFFER_SIZE);
+            return repeating;
+            break;
+
+          default:
+            if ((pos < (RTEMS_COMMAND_BUFFER_SIZE - 1)) &&
+                (c >= ' ') && (c <= 'z'))
+            {
+              int end;
+              if (c >= 'A' && c <= 'Z')
+                c += 'a' - 'A';
+              end = strlen (buffer);
+              if ((pos < end) && (end < RTEMS_COMMAND_BUFFER_SIZE))
+              {
+                int ch, bs;
+                for (ch = end + 1; ch > pos; ch--)
+                  buffer[ch] = buffer[ch - 1];
+                printf (buffer + pos);
+                for (bs = 0; bs < (end - pos + 1); bs++)
+                  putchar ('\b');
+              }
+              buffer[pos++] = c;
+              if (pos > end)
+                buffer[pos] = '\0';
+              putchar (c);
+            }
+            break;
+        }
+      }
+    }
+  }
+}
+
+/*
  * make_argv(cp): token-count
- *	Break up the command line in 'cp' into global argv[] and argc (return
- *	value).
+ *  Break up the command line in 'cp' into global argv[] and argc (return
+ *  value).
  */
 
 int
@@ -25,16 +436,16 @@ rtems_monitor_make_argv(
     int  *argc_p,
     char **argv)
 {
-    int argc = 0;
+  int argc = 0;
 
-    while ((cp = strtok(cp, " \t\n\r")))
-    {
-	argv[argc++] = cp;
-	cp = (char *) NULL;
-    }
-    argv[argc] = (char *) NULL;			/* end of argv */
+  while ((cp = strtok(cp, " \t\n\r")))
+  {
+    argv[argc++] = cp;
+    cp = (char *) NULL;
+  }
+  argv[argc] = (char *) NULL;      /* end of argv */
 
-    return *argc_p = argc;
+  return *argc_p = argc;
 }
 
 
@@ -50,34 +461,29 @@ rtems_monitor_command_read(char *command,
                            int  *argc,
                            char **argv)
 {
-    static char monitor_prompt[32];
-    
-    /*
-     * put node number in the prompt if we are multiprocessing
-     */
+  /*
+   * put node number in the prompt if we are multiprocessing
+   */
 
-    if (!rtems_configuration_get_user_multiprocessing_table())
-        sprintf(monitor_prompt, "%s", MONITOR_PROMPT);
-    else if (rtems_monitor_default_node != rtems_monitor_node)
-        sprintf(monitor_prompt, "%d-%s-%d", rtems_monitor_node, MONITOR_PROMPT, rtems_monitor_default_node);
-    else
-        sprintf(monitor_prompt, "%d-%s", rtems_monitor_node, MONITOR_PROMPT);
+  if (!rtems_configuration_get_user_multiprocessing_table ())
+    sprintf (monitor_prompt, "%s", MONITOR_PROMPT);
+  else if (rtems_monitor_default_node != rtems_monitor_node)
+    sprintf (monitor_prompt, "%d-%s-%d", rtems_monitor_node,
+             MONITOR_PROMPT, rtems_monitor_default_node);
+  else
+    sprintf (monitor_prompt, "%d-%s", rtems_monitor_node, MONITOR_PROMPT);
 
 #ifdef RTEMS_UNIX
-    /* RTEMS on unix gets so many interrupt system calls this is hosed */
-    printf("%s> ", monitor_prompt);
-    fflush(stdout);
-    while (gets(command) == (char *) 0)
-        ;
+  /* RTEMS on unix gets so many interrupt system calls this is hosed */
+  printf ("%s> ", monitor_prompt);
+  fflush (stdout);
+  while (gets(command) == (char *) 0)
+    ;
 #else
-    do
-    {
-        printf("%s> ", monitor_prompt);
-        fflush(stdout);
-    } while (gets(command) == (char *) 0);
+  rtems_monitor_line_editor (command);
 #endif
 
-    return rtems_monitor_make_argv(command, argc, argv);
+  return rtems_monitor_make_argv (command, argc, argv);
 }
 
 /*
@@ -92,74 +498,177 @@ rtems_monitor_command_lookup(
     char                          **argv
 )
 {
-    rtems_monitor_command_entry_t *p;
-    rtems_monitor_command_entry_t *abbreviated_match = 0;
-    int abbreviated_matches = 0;
-    char *command;
-    int command_length;
+  char *command;
 
-    command = argv[0];
+  command = argv[0];
 
-    if ((table == 0) || (command == 0))
-        goto failed;
+  if ((table == 0) || (command == 0))
+    return 0;
     
-    command_length = strlen(command);
+  while (table)
+  {
+    if (table->command)
+    {
+      if (STREQ (command, table->command))  /* exact match */
+      {
+        if (table->command_function == 0)
+          return 0;
+        return table;
+      }
+    }
+    table = table->next;
+  }
 
-    for (p = table; p->command; p++)
-        if (STREQ(command, p->command))    /* exact match */
-            goto done;
-        else if (STRNEQ(command, p->command, command_length))
-        {
-            abbreviated_matches++;
-            abbreviated_match = p;
-        }
+  return 0;
+}
 
-    /* no perfect match; is there a non-ambigous abbreviated match? */
-    if ( ! abbreviated_match)
-    {
-        printf("Unrecognized command '%s'; try 'help'\n", command);
-        goto failed;
-    }    
+void
+rtems_monitor_show_help (
+  rtems_monitor_command_entry_t *help_cmd,
+  int                           max_cmd_len
+)
+{
+#define MAX_HELP_LINE_LENGTH (75 - max_cmd_len - 2)
+
+  if (help_cmd && help_cmd->command)
+  {
+    const char *help = help_cmd->usage;
+    int         help_len = strlen (help);
+    int         spaces = max_cmd_len - strlen (help_cmd->command);
+    int         show_this_line = 0;
+    int         line_one = 1;
+    int         c;
 
-    if (abbreviated_matches > 1)
+    printf ("%s", help_cmd->command);
+
+    if (help_len == 0)
     {
-        printf("Command '%s' is ambiguous; try 'help'\n", command);
-        goto failed;
+      printf (" - No help associated.\n");
+      return;
     }
-    
-    p = abbreviated_match;
+  
+    while (help_len)
+    {
+      printf ("%*c", spaces, ' ');
+      
+      if (line_one)
+        printf (" - ");
 
-done:
-    if (p->command_function == 0)
-        goto failed;
-    return p;
+      spaces   = max_cmd_len + 2;
+      line_one = 0;
 
-failed:
-    return 0;
+      /*
+       * See if greater then the line length if so, work back
+       * from the end for a space, tab or lf or cr.
+       */
+     
+      if (help_len > MAX_HELP_LINE_LENGTH)
+      {
+        for (show_this_line = MAX_HELP_LINE_LENGTH - 1; 
+             show_this_line; 
+             show_this_line--)
+          if ((help[show_this_line] == ' ') ||
+              (help[show_this_line] == '\n') ||
+              (help[show_this_line] == '\r'))
+            break;
+
+        /*
+         * If show_this_line is 0, it is a very long word !!
+         */
+      
+        if (show_this_line == 0)
+          show_this_line = MAX_HELP_LINE_LENGTH - 1;
+      }
+      else
+        show_this_line = help_len;
+
+      for (c = 0; c < show_this_line; c++)
+        if ((help[c] == '\r') || (help[c] == '\n'))
+          show_this_line = c;
+        else
+          putchar (help[c]);
+
+      printf ("\n");
+                  
+      help     += show_this_line;
+      help_len -= show_this_line;
+
+      /*
+       * Move past the line feeds or what ever else is being skipped.
+       */
+    
+      while (help_len)
+      {
+        if ((*help != '\r') && (*help != '\n'))
+          break;
+
+        if (*help != ' ')
+        {
+          help++;
+          help_len--;
+          break;
+        }
+        help++;
+        help_len--;
+      }
+    }
+  }
 }
 
 void
-rtems_monitor_command_usage(rtems_monitor_command_entry_t *table,
-                            char *command_string)
+rtems_monitor_command_usage(
+  rtems_monitor_command_entry_t *table,
+  char                          *command_string
+)
 {
-    rtems_monitor_command_entry_t *help = 0;
-    char *help_command_argv[2];
+  rtems_monitor_command_entry_t *command = table;
+  int                           max_cmd_len = 0;
     
-    /* if first entry in table is a usage, then print it out */
-    if (command_string == 0)
-    {        
-        if (STREQ(table->command, "--usage--") && table->usage)
-            help = table;
-    }
+  /* if first entry in table is a usage, then print it out */
+
+  if (command_string && (*command_string != '\0'))
+  {
+    char *argv[2];
+    
+    argv[0] = command_string;
+    argv[1] = 0;
+    
+    command = rtems_monitor_command_lookup (table, 1, argv);
+
+    if (command)
+      rtems_monitor_show_help (command, strlen (command_string));
     else
-    {
-        help_command_argv[0] = command_string;
-        help_command_argv[1] = 0;
-        help = rtems_monitor_command_lookup(table, 1, help_command_argv);
-    }
+      printf ("Unrecognised command; try just 'help'\n");
+    return;
+  }
+  
+  /*
+   * Find the largest command size.
+   */
+  
+  while (command)
+  {
+    int len = strlen (command->command);
+
+    if (len > max_cmd_len)
+      max_cmd_len = len;
 
-    if (help)
-        printf("%s\n", help->usage);
+    command = command->next;
+  }
+
+  max_cmd_len++;
+
+  command = table;
+
+  /*
+   * Now some nice formatting for the help.
+   */
+
+  while (command)
+  {
+    rtems_monitor_show_help (command, max_cmd_len);
+    command = command->next;
+  }
 }
 
 
@@ -171,16 +680,16 @@ rtems_monitor_help_cmd(
     boolean verbose
 )
 {
-    int arg;
-    rtems_monitor_command_entry_t *command;
+  int arg;
+  rtems_monitor_command_entry_t *command;
 
-    command = (rtems_monitor_command_entry_t *) command_arg;
+  command = (rtems_monitor_command_entry_t *) command_arg;
     
-    if (argc == 1)
-        rtems_monitor_command_usage(command, 0);
-    else
-    {
-        for (arg=1; argv[arg]; arg++)
-            rtems_monitor_command_usage(command, argv[arg]);
-    }
+  if (argc == 1)
+    rtems_monitor_command_usage(command, 0);
+  else
+  {
+    for (arg = 1; argv[arg]; arg++)
+      rtems_monitor_command_usage(command, argv[arg]);
+  }
 }
diff --git a/c/src/libmisc/monitor/mon-monitor.c b/c/src/libmisc/monitor/mon-monitor.c
index 289425d8e4..478e904feb 100644
--- a/c/src/libmisc/monitor/mon-monitor.c
+++ b/c/src/libmisc/monitor/mon-monitor.c
@@ -27,6 +27,7 @@
 #include <stdio.h>
 #include <string.h>
 #include <stdlib.h>
+#include <termios.h>
 #include <unistd.h>
 
 #include <rtems/monitor.h>
@@ -54,186 +55,174 @@ unsigned32 rtems_monitor_default_node;  /* current default for commands */
 rtems_symbol_table_t *rtems_monitor_symbols;
 
 /*
+ * User registered commands.
+ */
+
+rtems_monitor_command_entry_t rtems_registered_commands;
+
+/*
  * The top-level commands
  */
 
 rtems_monitor_command_entry_t rtems_monitor_commands[] = {
-    { "--usage--",
-      "\n"
-      "RTEMS monitor\n"
-      "\n"
-      "Commands (may be abbreviated)\n"
-      "\n"
-      "  help      -- get this message or command specific help\n"
-      "  pause     -- pause monitor for a specified number of ticks\n"
-      "  exit      -- invoke a fatal RTEMS error\n"
-      "  symbol    -- show entries from symbol table\n"
-      "  continue  -- put monitor to sleep waiting for explicit wakeup\n"
-      "  config    -- show system configuration\n"
-      "  itask     -- list init tasks\n"
-      "  mpci      -- list mpci config\n"
-      "  task      -- show task information\n"
-      "  queue     -- show message queue information\n"
-      "  extension -- user extensions\n"
-      "  driver    -- show information about named drivers\n"
-      "  dname     -- show information about named drivers\n"
-      "  object    -- generic object information\n"
-      "  node      -- specify default node for commands that take id's\n"
-#ifdef CPU_INVOKE_DEBUGGER
-      "  debugger  -- invoke system debugger\n"
-#endif
-      ,
-      0,
-      0,
-      (unsigned32) rtems_monitor_commands,
-    },
     { "config",
-      "config\n"
-      "  Show the system configuration.\n",
+      "Show the system configuration.",
       0,
       rtems_monitor_object_cmd,
       RTEMS_MONITOR_OBJECT_CONFIG,
+      &rtems_monitor_commands[1],
     },
     { "itask",
-      "itask\n"
-      "  List init tasks for the system\n",
+      "List init tasks for the system",
       0,
       rtems_monitor_object_cmd,
       RTEMS_MONITOR_OBJECT_INIT_TASK,
+      &rtems_monitor_commands[2],
     }, 
    { "mpci",
-      "mpci\n"
-      "  Show the MPCI system configuration, if configured.\n",
+      "Show the MPCI system configuration, if configured.",
       0,
       rtems_monitor_object_cmd,
       RTEMS_MONITOR_OBJECT_MPCI,
+      &rtems_monitor_commands[3],
     },
     { "pause",
-      "pause [ticks]\n"
-      "  monitor goes to \"sleep\" for specified ticks (default is 1)\n"
-      "  monitor will resume at end of period or if explicitly awakened\n",
+      "Monitor goes to \"sleep\" for specified ticks (default is 1). "
+      "Monitor will resume at end of period or if explicitly awakened\n"
+      "  pause [ticks]",
       0,
       rtems_monitor_pause_cmd,
       0,
+      &rtems_monitor_commands[4],
     },
     { "continue",
-      "continue\n"
-      "  put the monitor to sleep waiting for an explicit wakeup from the\n"
-      "  program running.\n",
+      "Put the monitor to sleep waiting for an explicit wakeup from the "
+      "program running.\n",
       0,
       rtems_monitor_continue_cmd,
       0,
+      &rtems_monitor_commands[5],
     },
     { "go",
-      "go\n"
-      "  Alias for 'continue'\n",
+      "Alias for 'continue'",
       0,
       rtems_monitor_continue_cmd,
       0,
+      &rtems_monitor_commands[6],
     },
     { "node",
-      "node [ node number ]\n"
-      "  Specify default node number for commands that take id's\n",
+      "Specify default node number for commands that take id's.\n"
+      "  node [ node number ]",
       0,
       rtems_monitor_node_cmd,
       0,
+      &rtems_monitor_commands[7],
     },
     { "symbol",
-      "symbol [ symbolname [symbolname ... ] ]\n"
-      "  display value associated with specified symbol.\n"
-      "  Defaults to displaying all known symbols.\n",
+      "Display value associated with specified symbol. "
+      "Defaults to displaying all known symbols.\n"
+      "  symbol [ symbolname [symbolname ... ] ]",
       0,
       rtems_monitor_symbol_cmd,
       (unsigned32) &rtems_monitor_symbols,
+      &rtems_monitor_commands[8],
     },
     { "extension",
-      "extension [id [id ...] ]\n"
-      "  display information about specified extensions.\n"
-      "  Default is to display information about all extensions on this node\n",
+      "Display information about specified extensions. "
+      "Default is to display information about all extensions on this node.\n"
+      "  extension [id [id ...] ]",
       0,
       rtems_monitor_object_cmd,
       RTEMS_MONITOR_OBJECT_EXTENSION,
+      &rtems_monitor_commands[9],
     },
     { "task",
-      "task [id [id ...] ]\n"
-      "  display information about the specified tasks.\n"
-      "  Default is to display information about all tasks on this node\n",
+      "Display information about the specified tasks. "
+      "Default is to display information about all tasks on this node.\n"
+      "  task [id [id ...] ]",
       0,
       rtems_monitor_object_cmd,
       RTEMS_MONITOR_OBJECT_TASK,
+      &rtems_monitor_commands[10],
     },
     { "queue",
-      "queue [id [id ... ] ]\n"
-      "  display information about the specified message queues\n"
-      "  Default is to display information about all queues on this node\n",
+      "Display information about the specified message queues. "
+      "Default is to display information about all queues on this node.\n"
+      "  queue [id [id ... ] ]",
       0,
       rtems_monitor_object_cmd,
       RTEMS_MONITOR_OBJECT_QUEUE,
+      &rtems_monitor_commands[11],
     },
     { "object",
-      "object [id [id ...] ]\n"
-      "  display information about specified RTEMS objects.\n"
-      "  Object id's must include 'type' information.\n"
-      "  (which may normally be defaulted)\n",
+      "Display information about specified RTEMS objects. "
+      "Object id's must include 'type' information. "
+      "(which may normally be defaulted)\n"
+      "  object [id [id ...] ]",
       0,
       rtems_monitor_object_cmd,
       RTEMS_MONITOR_OBJECT_INVALID,
+      &rtems_monitor_commands[12],
     },
     { "driver",
-      "driver [ major [ major ... ] ]\n"
-      "  Display the RTEMS device driver table.\n",
+      "Display the RTEMS device driver table.\n"
+      "  driver [ major [ major ... ] ]",
       0,
       rtems_monitor_object_cmd,
       RTEMS_MONITOR_OBJECT_DRIVER,
+      &rtems_monitor_commands[13],
     },
     { "dname",
-      "dname\n"
-      "  Displays information about named drivers.\n",
+      "Displays information about named drivers.\n",
       0,
       rtems_monitor_object_cmd,
       RTEMS_MONITOR_OBJECT_DNAME,
+      &rtems_monitor_commands[14],
     },
     { "exit",
-      "exit [status]\n"
-      "  Invoke 'rtems_fatal_error_occurred' with 'status'\n"
-      "  (default is RTEMS_SUCCESSFUL)\n",
+      "Invoke 'rtems_fatal_error_occurred' with 'status' "
+      "(default is RTEMS_SUCCESSFUL)\n"
+      "  exit [status]",
       0,
       rtems_monitor_fatal_cmd,
       RTEMS_SUCCESSFUL,
+      &rtems_monitor_commands[15],
     },
     { "fatal",
-      "fatal [status]\n"
-      "  'exit' with fatal error; default error is RTEMS_TASK_EXITTED\n",
+      "'exit' with fatal error; default error is RTEMS_TASK_EXITTED\n"
+      "  fatal [status]",
       0,
       rtems_monitor_fatal_cmd,
       RTEMS_TASK_EXITTED,			/* exit value */
+      &rtems_monitor_commands[16],
     },
     { "quit",
-      "quit [status]\n"
-      "  Alias for 'exit'\n",
+      "Alias for 'exit'\n",
       0,
       rtems_monitor_fatal_cmd,
       RTEMS_SUCCESSFUL,				/* exit value */
+      &rtems_monitor_commands[17],
     },
     { "help",
-      "help [ command [ command ] ]\n"
-      "  provide information about commands\n"
-      "  Default is show basic command summary.\n",
+      "Provide information about commands. "
+      "Default is show basic command summary.\n"
+      "help [ command [ command ] ]",
       0,
       rtems_monitor_help_cmd,
       (unsigned32) rtems_monitor_commands,
+      &rtems_monitor_commands[18],
     },
 #ifdef CPU_INVOKE_DEBUGGER
     { "debugger",
-      "debugger\n"
-      "  Enter the debugger, if possible.\n"
-      "  A continue from the debugger will return to the monitor.\n",
+      "Enter the debugger, if possible. "
+      "A continue from the debugger will return to the monitor.\n",
       0,
       rtems_monitor_debugger_cmd,
       0,
+      &rtems_monitor_commands[19],
     },
 #endif            
-    { 0, 0, 0, 0, 0 },
+    { 0, 0, 0, 0, 0, &rtems_registered_commands },
 };
 
 
@@ -418,6 +407,56 @@ done:
     return;
 }
 
+/*
+ * User registered commands.
+ */
+
+int
+rtems_monitor_insert_cmd (
+    rtems_monitor_command_entry_t *command
+)
+{
+    rtems_monitor_command_entry_t *p = rtems_registered_commands.next;
+
+    command->next = 0;
+
+    if (rtems_registered_commands.next)
+    {
+        for (; p->next; p = p->next)
+        {
+            if (STREQ(command->command, p->command))
+                return 0;
+        }
+        p->next = command;
+    }
+    else
+        rtems_registered_commands.next = command;
+  
+    return 1;
+}
+
+int
+rtems_monitor_erase_cmd (
+    rtems_monitor_command_entry_t *command
+)
+{
+    rtems_monitor_command_entry_t *p;
+    rtems_monitor_command_entry_t **p_prev = &rtems_registered_commands.next;
+
+    if (rtems_registered_commands.next)
+    {
+        for (p = rtems_registered_commands.next; p->next; p = p->next)
+        {
+            if (STREQ(command->command, p->command))
+            {
+                *p_prev = p->next;
+                return 1;
+            }
+            p_prev = &p->next;
+        }
+    }
+    return 0;
+}
 
 /*
  * Main monitor command loop
@@ -435,7 +474,39 @@ rtems_monitor_task(
     int argc;
     char *argv[64];        
     boolean verbose = FALSE;
+    struct termios term;
 
+    /*
+     * Make the stdin stream characte not line based.
+     */
+    
+    if (tcgetattr (STDIN_FILENO, &term) < 0)
+    {
+      printf("rtems-monitor: cannot get terminal attributes.\n");
+    }
+    else
+    {
+      /*
+       * No echo, no canonical processing.
+       */
+
+      term.c_lflag &= ~(ECHO | ICANON | IEXTEN);
+  
+      /*
+       * No sigint on BREAK, CR-to-NL off, input parity off,
+       * don't strip 8th bit on input, output flow control off
+       */
+
+      term.c_lflag    &= ~(INPCK | ISTRIP | IXON);
+      term.c_cc[VMIN]  = 1;
+      term.c_cc[VTIME] = 0;
+
+      if (tcsetattr (STDIN_FILENO, TCSANOW, &term) < 0)
+      {
+        printf("cannot set terminal attributes\n");
+      }
+    }
+    
     if (monitor_flags & RTEMS_MONITOR_SUSPEND)
         (void) rtems_monitor_suspend(RTEMS_NO_TIMEOUT);
 
@@ -453,7 +524,11 @@ rtems_monitor_task(
         if ((command = rtems_monitor_command_lookup(rtems_monitor_commands,
                                                     argc,
                                                     argv)) == 0)
+        {
+            /* no command */
+            printf("Unrecognised command; try 'help'\n");
             continue;
+        }
 
         command->command_function(argc, argv, command->command_arg, verbose);
 
diff --git a/c/src/libmisc/monitor/monitor.h b/c/src/libmisc/monitor/monitor.h
index a9584808f3..ef0e099ac7 100644
--- a/c/src/libmisc/monitor/monitor.h
+++ b/c/src/libmisc/monitor/monitor.h
@@ -294,9 +294,9 @@ struct rtems_monitor_command_entry_s {
     char        *usage;        /* usage string for the command */
     unsigned32   arguments_required;    /* # of required args */
     rtems_monitor_command_function_t command_function;
-
                                /* Some argument for the command */
-    unsigned32          command_arg;
+    unsigned32   command_arg;
+    struct rtems_monitor_command_entry_s *next;
 };
 
 typedef void *(*rtems_monitor_object_next_fn)(void *, void *, rtems_id *);
@@ -325,6 +325,9 @@ void    rtems_monitor_continue_cmd(int, char **, unsigned32, boolean);
 void    rtems_monitor_debugger_cmd(int, char **, unsigned32, boolean);
 void    rtems_monitor_node_cmd(int, char **, unsigned32, boolean);
 void    rtems_monitor_symbols_loadup(void);
+int     rtems_monitor_insert_cmd(rtems_monitor_command_entry_t *);
+int     rtems_monitor_erase_cmd(rtems_monitor_command_entry_t *);
+
 void    rtems_monitor_task(rtems_task_argument);
 
 /* server.c */