gdb/target.h

   1 /* Interface between GDB and target environments, including files and processes
   2    Copyright 1990, 1991, 1992 Free Software Foundation, Inc.
   3    Contributed by Cygnus Support.  Written by John Gilmore.
   4
   5 This file is part of GDB.
   6
   7 This program is free software; you can redistribute it and/or modify
   8 it under the terms of the GNU General Public License as published by
   9 the Free Software Foundation; either version 2 of the License, or
  10 (at your option) any later version.
  11
  12 This program is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 GNU General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with this program; if not, write to the Free Software
  19 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */
  20
  21 #if !defined (TARGET_H)
  22 #define TARGET_H
  23
  24 /* This include file defines the interface between the main part
  25    of the debugger, and the part which is target-specific, or
  26    specific to the communications interface between us and the
  27    target.
  28
  29    A TARGET is an interface between the debugger and a particular
  30    kind of file or process.  Targets can be STACKED in STRATA,
  31    so that more than one target can potentially respond to a request.
  32    In particular, memory accesses will walk down the stack of targets
  33    until they find a target that is interested in handling that particular
  34    address.  STRATA are artificial boundaries on the stack, within
  35    which particular kinds of targets live.  Strata exist so that
  36    people don't get confused by pushing e.g. a process target and then
  37    a file target, and wondering why they can't see the current values
  38    of variables any more (the file target is handling them and they
  39    never get to the process target).  So when you push a file target,
  40    it goes into the file stratum, which is always below the process
  41    stratum.  */
  42
  43 #include "bfd.h"
  44
  45 enum strata {
  46         dummy_stratum,          /* The lowest of the low */
  47         file_stratum,           /* Executable files, etc */
  48         core_stratum,           /* Core dump files */
  49         process_stratum         /* Executing processes */
  50 };
  51
  52 struct target_ops
  53 {
  54   char         *to_shortname;   /* Name this target type */
  55   char         *to_longname;    /* Name for printing */
  56   char         *to_doc;         /* Documentation.  Does not include trailing
  57                                    newline, and starts with a one-line descrip-
  58                                    tion (probably similar to to_longname). */
  59   void        (*to_open) PARAMS ((char *, int));
  60   void        (*to_close) PARAMS ((int));
  61   void        (*to_attach) PARAMS ((char *, int));
  62   void        (*to_detach) PARAMS ((char *, int));
  63   void        (*to_resume) PARAMS ((int, int));
  64   int         (*to_wait) PARAMS ((int *));
  65   void        (*to_fetch_registers) PARAMS ((int));
  66   void        (*to_store_registers) PARAMS ((int));
  67   void        (*to_prepare_to_store) PARAMS ((void));
  68   void        (*to_convert_to_virtual) PARAMS ((int, char *, char *));
  69   void        (*to_convert_from_virtual) PARAMS ((int, char *, char *));
  70   int         (*to_xfer_memory) PARAMS ((CORE_ADDR, char *, int, int,
  71                                          struct target_ops *));
  72   void        (*to_files_info) PARAMS ((struct target_ops *));
  73   int         (*to_insert_breakpoint) PARAMS ((CORE_ADDR, char *));
  74   int         (*to_remove_breakpoint) PARAMS ((CORE_ADDR, char *));
  75   void        (*to_terminal_init) PARAMS ((void));
  76   void        (*to_terminal_inferior) PARAMS ((void));
  77   void        (*to_terminal_ours_for_output) PARAMS ((void));
  78   void        (*to_terminal_ours) PARAMS ((void));
  79   void        (*to_terminal_info) PARAMS ((char *, int));
  80   void        (*to_kill) PARAMS ((void));
  81   void        (*to_load) PARAMS ((char *, int));
  82   int         (*to_lookup_symbol) PARAMS ((char *, CORE_ADDR *));
  83   void        (*to_create_inferior) PARAMS ((char *, char *, char **));
  84   void        (*to_mourn_inferior) PARAMS ((void));
  85   enum strata   to_stratum;
  86   struct target_ops
  87                *to_next;
  88   int           to_has_all_memory;
  89   int           to_has_memory;
  90   int           to_has_stack;
  91   int           to_has_registers;
  92   int           to_has_execution;
  93   struct section_table
  94                *to_sections;
  95   struct section_table
  96                *to_sections_end;
  97   int           to_magic;
  98   /* Need sub-structure for target machine related rather than comm related? */
  99 };
 100
 101 /* Magic number for checking ops size.  If a struct doesn't end with this
 102    number, somebody changed the declaration but didn't change all the
 103    places that initialize one.  */
 104
 105 #define OPS_MAGIC       3840
 106
 107 /* The ops structure for our "current" target process.  */
 108
 109 extern struct target_ops        *current_target;
 110
 111 /* Define easy words for doing these operations on our current target.  */
 112
 113 #define target_shortname        (current_target->to_shortname)
 114 #define target_longname         (current_target->to_longname)
 115
 116 /* The open routine takes the rest of the parameters from the command,
 117    and (if successful) pushes a new target onto the stack.
 118    Targets should supply this routine, if only to provide an error message.  */
 119 #define target_open(name, from_tty)     \
 120         (*current_target->to_open) (name, from_tty)
 121
 122 /* Does whatever cleanup is required for a target that we are no longer
 123    going to be calling.  Argument says whether we are quitting gdb and
 124    should not get hung in case of errors, or whether we want a clean
 125    termination even if it takes a while.  This routine is automatically
 126    always called just before a routine is popped off the target stack.
 127    Closing file descriptors and freeing memory are typical things it should
 128    do.  */
 129
 130 #define target_close(quitting)  \
 131         (*current_target->to_close) (quitting)
 132
 133 /* Attaches to a process on the target side.  */
 134
 135 #define target_attach(args, from_tty)   \
 136         (*current_target->to_attach) (args, from_tty)
 137
 138 /* Takes a program previously attached to and detaches it.
 139    The program may resume execution (some targets do, some don't) and will
 140    no longer stop on signals, etc.  We better not have left any breakpoints
 141    in the program or it'll die when it hits one.  ARGS is arguments
 142    typed by the user (e.g. a signal to send the process).  FROM_TTY
 143    says whether to be verbose or not.  */
 144
 145 #define target_detach(args, from_tty)           \
 146         (*current_target->to_detach) (args, from_tty)
 147
 148 /* Resume execution of the target process.  STEP says whether to single-step
 149    or to run free; SIGGNAL is the signal value (e.g. SIGINT) to be given
 150    to the target, or zero for no signal.  */
 151
 152 #define target_resume(step, siggnal)    \
 153         (*current_target->to_resume) (step, siggnal)
 154
 155 /* Wait for inferior process to do something.  Return pid of child,
 156    or -1 in case of error; store status through argument pointer STATUS.  */
 157
 158 #define target_wait(status)             \
 159         (*current_target->to_wait) (status)
 160
 161 /* Fetch register REGNO, or all regs if regno == -1.  No result.  */
 162
 163 #define target_fetch_registers(regno)   \
 164         (*current_target->to_fetch_registers) (regno)
 165
 166 /* Store at least register REGNO, or all regs if REGNO == -1.
 167    It can store as many registers as it wants to, so the entire registers
 168    array must be valid.  Result is 0 for success, -1 for problems.  */
 169
 170 #define target_store_registers(regs)    \
 171         (*current_target->to_store_registers) (regs)
 172
 173 /* Get ready to modify the registers array.  On machines which store
 174    individual registers, this doesn't need to do anything.  On machines
 175    which store all the registers in one fell swoop, this makes sure
 176    that REGISTERS contains all the registers from the program being
 177    debugged.  */
 178
 179 #define target_prepare_to_store()       \
 180         (*current_target->to_prepare_to_store) ()
 181
 182 /* Convert data from raw format for register REGNUM
 183    to virtual format for register REGNUM.  */
 184
 185 #define target_convert_to_virtual(regnum, from, to)     \
 186         (*current_target->to_convert_to_virtual) (regnum, from, to)
 187
 188 /* Convert data from virtual format for register REGNUM
 189    to raw format for register REGNUM.  */
 190
 191 #define target_convert_from_virtual(regnum, from, to)   \
 192         (*current_target->to_convert_from_virtual) (regnum, from, to)
 193
 194 /* Reading and writing memory actually happens through a glue
 195    function which iterates across the various targets.  Result is
 196    0 for success, or an errno value.  */
 197
 198 extern int
 199 target_read_string PARAMS ((CORE_ADDR, char *, int));
 200
 201 extern int
 202 target_read_memory PARAMS ((CORE_ADDR, char *, int));
 203
 204 extern int
 205 target_write_memory PARAMS ((CORE_ADDR, char *, int));
 206
 207 extern int
 208 xfer_memory PARAMS ((CORE_ADDR, char *, int, int, struct target_ops *));
 209
 210 extern int
 211 child_xfer_memory PARAMS ((CORE_ADDR, char *, int, int, struct target_ops *));
 212
 213 extern int
 214 target_xfer_memory PARAMS ((CORE_ADDR, char *, int, int));
 215
 216 /* From exec.c */
 217
 218 extern void
 219 print_section_info PARAMS ((struct target_ops *, bfd *));
 220
 221 /* Print a line about the current target.  */
 222
 223 #define target_files_info()     \
 224         (*current_target->to_files_info) (current_target)
 225
 226 /* Insert a breakpoint at address ADDR in the target machine.
 227    SAVE is a pointer to memory allocated for saving the
 228    target contents.  It is guaranteed by the caller to be long enough
 229    to save "sizeof BREAKPOINT" bytes.  Result is 0 for success, or
 230    an errno value.  */
 231
 232 #define target_insert_breakpoint(addr, save)    \
 233         (*current_target->to_insert_breakpoint) (addr, save)
 234
 235 /* Remove a breakpoint at address ADDR in the target machine.
 236    SAVE is a pointer to the same save area
 237    that was previously passed to target_insert_breakpoint.
 238    Result is 0 for success, or an errno value.  */
 239
 240 #define target_remove_breakpoint(addr, save)    \
 241         (*current_target->to_remove_breakpoint) (addr, save)
 242
 243 /* Initialize the terminal settings we record for the inferior,
 244    before we actually run the inferior.  */
 245
 246 #define target_terminal_init() \
 247         (*current_target->to_terminal_init) ()
 248
 249 /* Put the inferior's terminal settings into effect.
 250    This is preparation for starting or resuming the inferior.  */
 251
 252 #define target_terminal_inferior() \
 253         (*current_target->to_terminal_inferior) ()
 254
 255 /* Put some of our terminal settings into effect,
 256    enough to get proper results from our output,
 257    but do not change into or out of RAW mode
 258    so that no input is discarded.
 259
 260    After doing this, either terminal_ours or terminal_inferior
 261    should be called to get back to a normal state of affairs.  */
 262
 263 #define target_terminal_ours_for_output() \
 264         (*current_target->to_terminal_ours_for_output) ()
 265
 266 /* Put our terminal settings into effect.
 267    First record the inferior's terminal settings
 268    so they can be restored properly later.  */
 269
 270 #define target_terminal_ours() \
 271         (*current_target->to_terminal_ours) ()
 272
 273 /* Print useful information about our terminal status, if such a thing
 274    exists.  */
 275
 276 #define target_terminal_info(arg, from_tty) \
 277         (*current_target->to_terminal_info) (arg, from_tty)
 278
 279 /* Kill the inferior process.   Make it go away.  */
 280
 281 #define target_kill() \
 282         (*current_target->to_kill) ()
 283
 284 /* Load an executable file into the target process.  This is expected to
 285    not only bring new code into the target process, but also to update
 286    GDB's symbol tables to match.  */
 287
 288 #define target_load(arg, from_tty) \
 289         (*current_target->to_load) (arg, from_tty)
 290
 291 /* Look up a symbol in the target's symbol table.  NAME is the symbol
 292    name.  ADDRP is a CORE_ADDR * pointing to where the value of the symbol
 293    should be returned.  The result is 0 if successful, nonzero if the
 294    symbol does not exist in the target environment.  This function should
 295    not call error() if communication with the target is interrupted, since
 296    it is called from symbol reading, but should return nonzero, possibly
 297    doing a complain().  */
 298
 299 #define target_lookup_symbol(name, addrp)       \
 300   (*current_target->to_lookup_symbol) (name, addrp)
 301
 302 /* Start an inferior process and set inferior_pid to its pid.
 303    EXEC_FILE is the file to run.
 304    ALLARGS is a string containing the arguments to the program.
 305    ENV is the environment vector to pass.  Errors reported with error().
 306    On VxWorks and various standalone systems, we ignore exec_file.  */
 307
 308 #define target_create_inferior(exec_file, args, env)    \
 309         (*current_target->to_create_inferior) (exec_file, args, env)
 310
 311 /* The inferior process has died.  Do what is right.  */
 312
 313 #define target_mourn_inferior() \
 314         (*current_target->to_mourn_inferior) ()
 315
 316 /* Pointer to next target in the chain, e.g. a core file and an exec file.  */
 317
 318 #define target_next \
 319         (current_target->to_next)
 320
 321 /* Does the target include all of memory, or only part of it?  This
 322    determines whether we look up the target chain for other parts of
 323    memory if this target can't satisfy a request.  */
 324
 325 #define target_has_all_memory   \
 326         (current_target->to_has_all_memory)
 327
 328 /* Does the target include memory?  (Dummy targets don't.)  */
 329
 330 #define target_has_memory       \
 331         (current_target->to_has_memory)
 332
 333 /* Does the target have a stack?  (Exec files don't, VxWorks doesn't, until
 334    we start a process.)  */
 335
 336 #define target_has_stack        \
 337         (current_target->to_has_stack)
 338
 339 /* Does the target have registers?  (Exec files don't.)  */
 340
 341 #define target_has_registers    \
 342         (current_target->to_has_registers)
 343
 344 /* Does the target have execution?  Can we make it jump (through hoops),
 345    or pop its stack a few times?  */
 346
 347 #define target_has_execution    \
 348         (current_target->to_has_execution)
 349
 350 /* Routines for maintenance of the target structures...
 351
 352    add_target:   Add a target to the list of all possible targets.
 353
 354    push_target:  Make this target the top of the stack of currently used
 355                  targets, within its particular stratum of the stack.  Result
 356                  is 0 if now atop the stack, nonzero if not on top (maybe
 357                  should warn user).
 358
 359    unpush_target: Remove this from the stack of currently used targets,
 360                  no matter where it is on the list.  Returns 0 if no
 361                  change, 1 if removed from stack.
 362
 363    pop_target:   Remove the top thing on the stack of current targets.  */
 364
 365 extern void
 366 add_target PARAMS ((struct target_ops *));
 367
 368 extern int
 369 push_target PARAMS ((struct target_ops *));
 370
 371 extern int
 372 unpush_target PARAMS ((struct target_ops *));
 373
 374 extern void
 375 target_preopen PARAMS ((int));
 376
 377 extern void
 378 pop_target PARAMS ((void));
 379
 380 /* Struct section_table maps address ranges to file sections.  It is
 381    mostly used with BFD files, but can be used without (e.g. for handling
 382    raw disks, or files not in formats handled by BFD).  */
 383
 384 struct section_table {
 385   CORE_ADDR addr;               /* Lowest address in section */
 386   CORE_ADDR endaddr;            /* 1+highest address in section */
 387   sec_ptr   sec_ptr;            /* BFD section pointer */
 388   bfd      *bfd;                /* BFD file pointer */
 389 };
 390
 391 /* Builds a section table, given args BFD, SECTABLE_PTR, SECEND_PTR.
 392    Returns 0 if OK, 1 on error.  */
 393
 394 extern int
 395 build_section_table PARAMS ((bfd *, struct section_table **,
 396                              struct section_table **));
 397
 398 /* From inftarg.c */
 399
 400 extern void
 401 host_convert_from_virtual PARAMS ((int, char *, char *));
 402
 403 extern void
 404 host_convert_to_virtual PARAMS ((int, char *, char *));
 405
 406 /* From mem-break.c */
 407
 408 extern int
 409 memory_remove_breakpoint PARAMS ((CORE_ADDR, char *));
 410
 411 extern int
 412 memory_insert_breakpoint PARAMS ((CORE_ADDR, char *));
 413
 414 #endif  /* !defined (TARGET_H) */