1/* Kernel Object Display generic routines and callbacks
2   Copyright 1998, 1999, 2000 Free Software Foundation, Inc.
3
4   Written by Fernando Nasser <fnasser@cygnus.com> for Cygnus Solutions.
5
6   This file is part of GDB.
7
8   This program is free software; you can redistribute it and/or modify
9   it under the terms of the GNU General Public License as published by
10   the Free Software Foundation; either version 2 of the License, or
11   (at your option) any later version.
12
13   This program is distributed in the hope that it will be useful,
14   but WITHOUT ANY WARRANTY; without even the implied warranty of
15   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16   GNU General Public License for more details.
17
18   You should have received a copy of the GNU General Public License
19   along with this program; if not, write to the Free Software
20   Foundation, Inc., 59 Temple Place - Suite 330,
21   Boston, MA 02111-1307, USA.  */
22
23#include "defs.h"
24#include "command.h"
25#include "gdbcmd.h"
26#include "target.h"
27#include "gdb_string.h"
28#include "kod.h"
29
30/* Prototypes for exported functions.  */
31void _initialize_kod (void);
32
33/* Prototypes for local functions.  */
34static void info_kod_command (char *, int);
35static void load_kod_library (char *);
36
37/* Prototypes for callbacks.  These are passed into the KOD modules.  */
38static void gdb_kod_display (char *);
39static void gdb_kod_query (char *, char *, int *);
40
41/* These functions are imported from the KOD module.
42
43   gdb_kod_open - initiates the KOD connection to the remote.  The
44   first argument is the display function the module should use to
45   communicate with the user.  The second argument is the query
46   function the display should use to communicate with the target.
47   This should call error() if there is an error.  Otherwise it should
48   return a malloc()d string of the form:
49
50   NAME VERSION - DESCRIPTION
51
52   Neither NAME nor VERSION should contain a hyphen.
53
54
55   gdb_kod_request - This is used when the user enters an "info
56   <module>" request.  The remaining arguments are passed as the first
57   argument.  The second argument is the standard `from_tty'
58   argument.
59
60
61   gdb_kod_close - This is called when the KOD connection to the
62   remote should be terminated.  */
63
64static char *(*gdb_kod_open) (kod_display_callback_ftype *display,
65			      kod_query_callback_ftype *query);
66static void (*gdb_kod_request) (char *, int);
67static void (*gdb_kod_close) ();
68
69
70/* Name of inferior's operating system.  */
71char *operating_system;
72
73/* We save a copy of the OS so that we can properly reset when
74   switching OS's.  */
75static char *old_operating_system;
76
77/* Print a line of data generated by the module.  */
78
79static void
80gdb_kod_display (char *arg)
81{
82  printf_filtered ("%s", arg);
83}
84
85/* Queries the target on behalf of the module.  */
86
87static void
88gdb_kod_query (char *arg, char *result, int *maxsiz)
89{
90  LONGEST bufsiz = 0;
91
92  /* Check if current target has remote_query capabilities.  If not,
93     it does not have kod either.  */
94  bufsiz = target_read_partial (&current_target, TARGET_OBJECT_KOD,
95				NULL, NULL, 0, 0);
96  if (bufsiz < 0)
97    {
98      strcpy (result,
99              "ERR: Kernel Object Display not supported by current target\n");
100      return;
101    }
102
103  /* Just get the maximum buffer size.  */
104
105  /* Check if *we* were called just for getting the buffer size.  */
106  if (*maxsiz == 0)
107    {
108      *maxsiz = bufsiz;
109      strcpy (result, "OK");
110      return;
111    }
112
113  /* Check if caller can handle a buffer this large, if not, adjust.  */
114  if (bufsiz > *maxsiz)
115    bufsiz = *maxsiz;
116
117  /* See if buffer can hold the query (usually it can, as the query is
118     short).  */
119  if (strlen (arg) >= bufsiz)
120    error ("kod: query argument too long");
121
122  /* Send actual request.  */
123  if (target_read_partial (&current_target, TARGET_OBJECT_KOD,
124			   arg, result, 0, bufsiz) < 0)
125    strcpy (result, "ERR: remote query failed");
126}
127
128/* Print name of kod command after selecting the appropriate kod
129   formatting library module.  As a side effect we create a new "info"
130   subcommand which is what the user actually uses to query the OS.  */
131
132static void
133kod_set_os (char *arg, int from_tty, struct cmd_list_element *command)
134{
135  char *p;
136
137  /* NOTE: cagney/2002-03-17: The add_show_from_set() function clones
138     the set command passed as a parameter.  The clone operation will
139     include (BUG?) any ``set'' command callback, if present.
140     Commands like ``info set'' call all the ``show'' command
141     callbacks.  Unfortunately, for ``show'' commands cloned from
142     ``set'', this includes callbacks belonging to ``set'' commands.
143     Making this worse, this only occures if add_show_from_set() is
144     called after add_cmd_sfunc() (BUG?).  */
145
146  if (cmd_type (command) != set_cmd)
147    return;
148
149  /* If we had already had an open OS, close it.  */
150  if (gdb_kod_close)
151    (*gdb_kod_close) ();
152
153  /* Also remove the old OS's command.  */
154  if (old_operating_system)
155    {
156      delete_cmd (old_operating_system, &infolist);
157      xfree (old_operating_system);
158    }
159
160  if (! operating_system || ! *operating_system)
161    {
162      /* If user set operating system to empty, we want to forget we
163	 had a module open.  Setting these variables is just nice for
164	 debugging and clarity.  */
165      gdb_kod_open = NULL;
166      gdb_kod_request = NULL;
167      gdb_kod_close = NULL;
168    }
169  else
170    {
171      char *kodlib;
172
173      old_operating_system = xstrdup (operating_system);
174
175      load_kod_library (operating_system);
176
177      kodlib = (*gdb_kod_open) (gdb_kod_display, gdb_kod_query);
178
179      /* Add kod related info commands to gdb.  */
180      add_info (operating_system, info_kod_command,
181		"Displays information about Kernel Objects.");
182
183      p = strrchr (kodlib, '-');
184      if (p != NULL)
185	p++;
186      else
187	p = "Unknown KOD library";
188      printf_filtered ("%s - %s\n", operating_system, p);
189
190      xfree (kodlib);
191    }
192}
193
194/* Print information about currently known kernel objects of the
195   specified type or a list of all known kernel object types if
196   argument is empty.  */
197
198static void
199info_kod_command (char *arg, int from_tty)
200{
201  (*gdb_kod_request) (arg, from_tty);
202}
203
204/* Print name of kod command after selecting the appropriate kod
205   formatting library module.  */
206
207static void
208load_kod_library (char *lib)
209{
210#if 0
211  /* FIXME: Don't have the eCos code here.  */
212  if (! strcmp (lib, "ecos"))
213    {
214      gdb_kod_open = ecos_kod_open;
215      gdb_kod_request = ecos_kod_request;
216      gdb_kod_close = ecos_kod_close;
217    }
218  else
219#endif /* 0 */
220   if (! strcmp (lib, "cisco"))
221    {
222      gdb_kod_open = cisco_kod_open;
223      gdb_kod_request = cisco_kod_request;
224      gdb_kod_close = cisco_kod_close;
225    }
226  else
227    error ("Unknown operating system: %s\n", operating_system);
228}
229
230void
231_initialize_kod (void)
232{
233  struct cmd_list_element *c;
234
235  c = add_set_cmd ("os", no_class, var_string,
236		   (char *) &operating_system,
237		   "Set operating system",
238		   &setlist);
239  set_cmd_sfunc (c, kod_set_os);
240  add_show_from_set (c, &showlist);
241}
242