gdb/kod.c

   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.  */
  31 void _initialize_kod (void);
  32
  33 /* Prototypes for local functions.  */
  34 static void info_kod_command (char *, int);
  35 static void load_kod_library (char *);
  36
  37 /* Prototypes for callbacks.  These are passed into the KOD modules.  */
  38 static void gdb_kod_display (char *);
  39 static 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
  64 static char *(*gdb_kod_open) (kod_display_callback_ftype *display,
  65                               kod_query_callback_ftype *query);
  66 static void (*gdb_kod_request) (char *, int);
  67 static void (*gdb_kod_close) ();
  68
  69
  70 /* Name of inferior's operating system.  */
  71 char *operating_system;
  72
  73 /* We save a copy of the OS so that we can properly reset when
  74    switching OS's.  */
  75 static char *old_operating_system;
  76
  77 /* Print a line of data generated by the module.  */
  78
  79 static void
  80 gdb_kod_display (char *arg)
  81 {
  82   printf_filtered ("%s", arg);
  83 }
  84
  85 /* Queries the target on behalf of the module.  */
  86
  87 static void
  88 gdb_kod_query (char *arg, char *result, int *maxsiz)
  89 {
  90   int bufsiz = 0;
  91
  92   /* Check if current target has remote_query capabilities.
  93      If not, it does not have kod either.  */
  94   if (! current_target.to_query)
  95     {
  96       strcpy (result,
  97               "ERR: Kernel Object Display not supported by current target\n");
  98       return;
  99     }
 100
 101   /* Just get the maximum buffer size.  */
 102   target_query ((int) 'K', 0, 0, &bufsiz);
 103
 104   /* Check if *we* were called just for getting the buffer size.  */
 105   if (*maxsiz == 0)
 106     {
 107       *maxsiz = bufsiz;
 108       strcpy (result, "OK");
 109       return;
 110     }
 111
 112   /* Check if caller can handle a buffer this large, if not, adjust.  */
 113   if (bufsiz > *maxsiz)
 114     bufsiz = *maxsiz;
 115
 116   /* See if buffer can hold the query (usually it can, as the query is
 117      short).  */
 118   if (strlen (arg) >= bufsiz)
 119     error ("kod: query argument too long");
 120
 121   /* Send actual request.  */
 122   if (target_query ((int) 'K', arg, result, &bufsiz))
 123     strcpy (result, "ERR: remote query failed");
 124 }
 125
 126 /* Print name of kod command after selecting the appropriate kod
 127    formatting library module.  As a side effect we create a new "info"
 128    subcommand which is what the user actually uses to query the OS.  */
 129
 130 static void
 131 kod_set_os (char *arg, int from_tty, struct cmd_list_element *command)
 132 {
 133   char *p;
 134
 135   /* NOTE: cagney/2002-03-17: This function gets called by the command
 136      ``info set'' with COMMAND pointing to a show_cmd rather than a
 137      set command.  This the test below is removed, a core dump results
 138      (think about what happens when OPERATING_SYSTEM is NULL).  The
 139      wiered thing is that all other ``set'' handlers don't need this
 140      test.  */
 141   if (command->type != set_cmd)
 142     return;
 143
 144   /* If we had already had an open OS, close it.  */
 145   if (gdb_kod_close)
 146     (*gdb_kod_close) ();
 147
 148   /* Also remove the old OS's command.  */
 149   if (old_operating_system)
 150     {
 151       delete_cmd (old_operating_system, &infolist);
 152       xfree (old_operating_system);
 153     }
 154
 155   if (! operating_system || ! *operating_system)
 156     {
 157       /* If user set operating system to empty, we want to forget we
 158          had a module open.  Setting these variables is just nice for
 159          debugging and clarity.  */
 160       gdb_kod_open = NULL;
 161       gdb_kod_request = NULL;
 162       gdb_kod_close = NULL;
 163     }
 164   else
 165     {
 166       char *kodlib;
 167
 168       old_operating_system = xstrdup (operating_system);
 169
 170       load_kod_library (operating_system);
 171
 172       kodlib = (*gdb_kod_open) (gdb_kod_display, gdb_kod_query);
 173
 174       /* Add kod related info commands to gdb.  */
 175       add_info (operating_system, info_kod_command,
 176                 "Displays information about Kernel Objects.");
 177
 178       p = strrchr (kodlib, '-');
 179       if (p != NULL)
 180         p++;
 181       else
 182         p = "Unknown KOD library";
 183       printf_filtered ("%s - %s\n", operating_system, p);
 184
 185       xfree (kodlib);
 186     }
 187 }
 188
 189 /* Print information about currently known kernel objects of the
 190    specified type or a list of all known kernel object types if
 191    argument is empty.  */
 192
 193 static void
 194 info_kod_command (char *arg, int from_tty)
 195 {
 196   (*gdb_kod_request) (arg, from_tty);
 197 }
 198
 199 /* Print name of kod command after selecting the appropriate kod
 200    formatting library module.  */
 201
 202 static void
 203 load_kod_library (char *lib)
 204 {
 205 #if 0
 206   /* FIXME: Don't have the eCos code here.  */
 207   if (! strcmp (lib, "ecos"))
 208     {
 209       gdb_kod_open = ecos_kod_open;
 210       gdb_kod_request = ecos_kod_request;
 211       gdb_kod_close = ecos_kod_close;
 212     }
 213   else
 214 #endif /* 0 */
 215    if (! strcmp (lib, "cisco"))
 216     {
 217       gdb_kod_open = cisco_kod_open;
 218       gdb_kod_request = cisco_kod_request;
 219       gdb_kod_close = cisco_kod_close;
 220     }
 221   else
 222     error ("Unknown operating system: %s\n", operating_system);
 223 }
 224
 225 void
 226 _initialize_kod (void)
 227 {
 228   struct cmd_list_element *c;
 229
 230   c = add_set_cmd ("os", no_class, var_string,
 231                    (char *) &operating_system,
 232                    "Set operating system",
 233                    &setlist);
 234   set_cmd_sfunc (c, kod_set_os);
 235   add_show_from_set (c, &showlist);
 236 }