libguile/gdbint.c

   1 /* GDB interface for Guile
   2  * Copyright (C) 1996,1997,1999,2000,2001,2002,2004
   3  * Free Software Foundation, Inc.
   4  *
   5  * This library is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU Lesser General Public
   7  * License as published by the Free Software Foundation; either
   8  * version 2.1 of the License, or (at your option) any later version.
   9  *
  10  * This library is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * Lesser General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU Lesser General Public
  16  * License along with this library; if not, write to the Free Software
  17  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  18  */
  19
  20 #if HAVE_CONFIG_H
  21 #  include <config.h>
  22 #endif
  23
  24 #include "libguile/_scm.h"
  25
  26 #include <stdio.h>
  27 #include <string.h>
  28 #ifdef HAVE_UNISTD_H
  29 #include <unistd.h>
  30 #endif
  31
  32 #include "libguile/strports.h"
  33 #include "libguile/read.h"
  34 #include "libguile/eval.h"
  35 #include "libguile/chars.h"
  36 #include "libguile/modules.h"
  37 #include "libguile/ports.h"
  38 #include "libguile/fluids.h"
  39 #include "libguile/strings.h"
  40 #include "libguile/init.h"
  41
  42 #include "libguile/gdbint.h"
  43 \f
  44 /* {Support for debugging with gdb}
  45  *
  46  * TODO:
  47  *
  48  * 1. Redirect outputs
  49  * 2. Catch errors
  50  * 3. Prevent print from causing segmentation fault when given broken pairs
  51  */
  52
  53 #define GDB_TYPE SCM
  54
  55 #include "libguile/gdb_interface.h"
  56
  57 \f
  58
  59 /* Be carefull when this macro is true.
  60    scm_gc_running_p is set during gc.
  61  */
  62 #define SCM_GC_P (scm_gc_running_p)
  63
  64 /* Macros that encapsulate blocks of code which can be called by the
  65  * debugger.
  66  */
  67 #define SCM_BEGIN_FOREIGN_BLOCK \
  68 do { \
  69   scm_print_carefully_p = 1; \
  70 } while (0)
  71
  72
  73 #define SCM_END_FOREIGN_BLOCK \
  74 do { \
  75   scm_print_carefully_p = 0; \
  76 } while (0)
  77
  78
  79 #define RESET_STRING { gdb_output_length = 0; }
  80
  81 #define SEND_STRING(str) \
  82 do { \
  83   gdb_output = (char *) (str); \
  84   gdb_output_length = strlen ((const char *) (str)); \
  85 } while (0)
  86
  87
  88 /* {Gdb interface}
  89  */
  90
  91 unsigned short gdb_options = GDB_HAVE_BINDINGS;
  92
  93 char *gdb_language = "lisp/c";
  94
  95 SCM gdb_result;
  96
  97 char *gdb_output;
  98
  99 int gdb_output_length;
 100
 101 int scm_print_carefully_p;
 102
 103 static SCM gdb_input_port;
 104 static int port_mark_p, stream_mark_p, string_mark_p;
 105
 106 static SCM gdb_output_port;
 107
 108
 109 static void
 110 unmark_port (SCM port)
 111 {
 112   SCM stream, string;
 113   port_mark_p = SCM_GC_MARK_P (port);
 114   SCM_CLEAR_GC_MARK (port);
 115   stream = SCM_PACK (SCM_STREAM (port));
 116   stream_mark_p = SCM_GC_MARK_P (stream);
 117   SCM_CLEAR_GC_MARK (stream);
 118   string = SCM_CDR (stream);
 119   string_mark_p = SCM_GC_MARK_P (string);
 120   SCM_CLEAR_GC_MARK (string);
 121 }
 122
 123
 124 static void
 125 remark_port (SCM port)
 126 {
 127   SCM stream = SCM_PACK (SCM_STREAM (port));
 128   SCM string = SCM_CDR (stream);
 129   if (string_mark_p)
 130     SCM_SET_GC_MARK (string);
 131   if (stream_mark_p)
 132     SCM_SET_GC_MARK (stream);
 133   if (port_mark_p)
 134     SCM_SET_GC_MARK (port);
 135 }
 136
 137
 138 int
 139 gdb_maybe_valid_type_p (SCM value)
 140 {
 141   return SCM_IMP (value) || scm_in_heap_p (value);
 142 }
 143
 144
 145 int
 146 gdb_read (char *str)
 147 {
 148   SCM ans;
 149   int status = 0;
 150   RESET_STRING;
 151   /* Need to be restrictive about what to read? */
 152   if (SCM_GC_P)
 153     {
 154       char *p;
 155       for (p = str; *p != '\0'; ++p)
 156         switch (*p)
 157           {
 158           case '(':
 159           case '\'':
 160           case '"':
 161             SEND_STRING ("Can't read this kind of expressions during gc");
 162             return -1;
 163           case '#':
 164             if (*++p == '\0')
 165               goto premature;
 166             if (*p == '\\')
 167               {
 168                 if (*++p != '\0')
 169                   continue;
 170               premature:
 171                 SEND_STRING ("Premature end of lisp expression");
 172                 return -1;
 173               }
 174           default:
 175             continue;
 176           }
 177     }
 178   SCM_BEGIN_FOREIGN_BLOCK;
 179   unmark_port (gdb_input_port);
 180   scm_seek (gdb_input_port, SCM_INUM0, scm_from_int (SEEK_SET));
 181   scm_puts (str, gdb_input_port);
 182   scm_truncate_file (gdb_input_port, SCM_UNDEFINED);
 183   scm_seek (gdb_input_port, SCM_INUM0, scm_from_int (SEEK_SET));
 184
 185   /* Read one object */
 186   ans = scm_read (gdb_input_port);
 187   if (SCM_GC_P)
 188     {
 189       if (SCM_NIMP (ans))
 190         {
 191           SEND_STRING ("Non-immediate created during gc.  Memory may be trashed.");
 192           status = -1;
 193           goto exit;
 194         }
 195     }
 196   gdb_result = ans;
 197   /* Protect answer from future GC */
 198   if (SCM_NIMP (ans))
 199     scm_permanent_object (ans);
 200 exit:
 201   remark_port (gdb_input_port);
 202   SCM_END_FOREIGN_BLOCK;
 203   return status;
 204 }
 205
 206
 207 int
 208 gdb_eval (SCM exp)
 209 {
 210   RESET_STRING;
 211   if (SCM_GC_P)
 212     {
 213       SEND_STRING ("Can't evaluate lisp expressions during gc");
 214       return -1;
 215     }
 216   SCM_BEGIN_FOREIGN_BLOCK;
 217   {
 218     SCM env = scm_top_level_env (SCM_TOP_LEVEL_LOOKUP_CLOSURE);
 219     gdb_result = scm_permanent_object (scm_i_eval_x (exp, env));
 220   }
 221   SCM_END_FOREIGN_BLOCK;
 222   return 0;
 223 }
 224
 225
 226 int
 227 gdb_print (SCM obj)
 228 {
 229   if (!scm_initialized_p)
 230     SEND_STRING ("*** Guile not initialized ***");
 231   else
 232     {
 233       RESET_STRING;
 234       SCM_BEGIN_FOREIGN_BLOCK;
 235       /* Reset stream */
 236       scm_seek (gdb_output_port, SCM_INUM0, scm_from_int (SEEK_SET));
 237       scm_write (obj, gdb_output_port);
 238       scm_truncate_file (gdb_output_port, SCM_UNDEFINED);
 239       {
 240         scm_t_port *pt = SCM_PTAB_ENTRY (gdb_output_port);
 241
 242         scm_flush (gdb_output_port);
 243         *(pt->write_buf + pt->read_buf_size) = 0;
 244         SEND_STRING (pt->read_buf);
 245       }
 246       SCM_END_FOREIGN_BLOCK;
 247     }
 248   return 0;
 249 }
 250
 251
 252 int
 253 gdb_binding (SCM name, SCM value)
 254 {
 255   RESET_STRING;
 256   if (SCM_GC_P)
 257     {
 258       SEND_STRING ("Can't create new bindings during gc");
 259       return -1;
 260     }
 261   SCM_BEGIN_FOREIGN_BLOCK;
 262   {
 263     SCM var = scm_sym2var (name, SCM_TOP_LEVEL_LOOKUP_CLOSURE, SCM_BOOL_T);
 264     SCM_VARIABLE_SET (var, value);
 265   }
 266   SCM_END_FOREIGN_BLOCK;
 267   return 0;
 268 }
 269
 270 void
 271 scm_init_gdbint ()
 272 {
 273   static char *s = "scm_init_gdb_interface";
 274   SCM port;
 275
 276   scm_print_carefully_p = 0;
 277
 278   port = scm_mkstrport (SCM_INUM0,
 279                         scm_c_make_string (0, SCM_UNDEFINED),
 280                         SCM_OPN | SCM_WRTNG,
 281                         s);
 282   gdb_output_port = scm_permanent_object (port);
 283
 284   port = scm_mkstrport (SCM_INUM0,
 285                         scm_c_make_string (0, SCM_UNDEFINED),
 286                         SCM_OPN | SCM_RDNG | SCM_WRTNG,
 287                         s);
 288   gdb_input_port = scm_permanent_object (port);
 289 }
 290
 291 /*
 292   Local Variables:
 293   c-file-style: "gnu"
 294   End:
 295 */