include/gdb/remote-sim.h

   1 /* This file defines the interface between the simulator and gdb.
   2
   3    Copyright 1993-2014 Free Software Foundation, Inc.
   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 3 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, see <http://www.gnu.org/licenses/>.  */
  19
  20 #if !defined (REMOTE_SIM_H)
  21 #define REMOTE_SIM_H 1
  22
  23 #ifdef __cplusplus
  24 extern "C" {
  25 #endif
  26
  27 /* This file is used when building stand-alone simulators, so isolate this
  28    file from gdb.  */
  29
  30 /* Pick up CORE_ADDR_TYPE if defined (from gdb), otherwise use same value as
  31    gdb does (unsigned int - from defs.h).  */
  32
  33 #ifndef CORE_ADDR_TYPE
  34 typedef unsigned int SIM_ADDR;
  35 #else
  36 typedef CORE_ADDR_TYPE SIM_ADDR;
  37 #endif
  38
  39
  40 /* Semi-opaque type used as result of sim_open and passed back to all
  41    other routines.  "desc" is short for "descriptor".
  42    It is up to each simulator to define `sim_state'.  */
  43
  44 typedef struct sim_state *SIM_DESC;
  45
  46
  47 /* Values for `kind' arg to sim_open.  */
  48
  49 typedef enum {
  50   SIM_OPEN_STANDALONE, /* simulator used standalone (run.c) */
  51   SIM_OPEN_DEBUG       /* simulator used by debugger (gdb) */
  52 } SIM_OPEN_KIND;
  53
  54
  55 /* Return codes from various functions.  */
  56
  57 typedef enum {
  58   SIM_RC_FAIL = 0,
  59   SIM_RC_OK = 1
  60 } SIM_RC;
  61
  62
  63 /* The bfd struct, as an opaque type.  */
  64
  65 struct bfd;
  66
  67
  68 /* Main simulator entry points.  */
  69
  70
  71 /* Create a fully initialized simulator instance.
  72
  73    (This function is called when the simulator is selected from the
  74    gdb command line.)
  75
  76    KIND specifies how the simulator shall be used.  Currently there
  77    are only two kinds: stand-alone and debug.
  78
  79    CALLBACK specifies a standard host callback (defined in callback.h).
  80
  81    ABFD, when non NULL, designates a target program.  The program is
  82    not loaded.
  83
  84    ARGV is a standard ARGV pointer such as that passed from the
  85    command line.  The syntax of the argument list is is assumed to be
  86    ``SIM-PROG { SIM-OPTION } [ TARGET-PROGRAM { TARGET-OPTION } ]''.
  87    The trailing TARGET-PROGRAM and args are only valid for a
  88    stand-alone simulator.
  89
  90    On success, the result is a non NULL descriptor that shall be
  91    passed to the other sim_foo functions.  While the simulator
  92    configuration can be parameterized by (in decreasing precedence)
  93    ARGV's SIM-OPTION, ARGV's TARGET-PROGRAM and the ABFD argument, the
  94    successful creation of the simulator shall not dependent on the
  95    presence of any of these arguments/options.
  96
  97    Hardware simulator: The created simulator shall be sufficiently
  98    initialized to handle, with out restrictions any client requests
  99    (including memory reads/writes, register fetch/stores and a
 100    resume).
 101
 102    Process simulator: that process is not created until a call to
 103    sim_create_inferior.  FIXME: What should the state of the simulator
 104    be? */
 105
 106 SIM_DESC sim_open (SIM_OPEN_KIND kind, struct host_callback_struct *callback, struct bfd *abfd, char **argv);
 107
 108
 109 /* Destory a simulator instance.
 110
 111    QUITTING is non-zero if we cannot hang on errors.
 112
 113    This may involve freeing target memory and closing any open files
 114    and mmap'd areas.  You cannot assume sim_kill has already been
 115    called. */
 116
 117 void sim_close (SIM_DESC sd, int quitting);
 118
 119
 120 /* Load program PROG into the simulators memory.
 121
 122    If ABFD is non-NULL, the bfd for the file has already been opened.
 123    The result is a return code indicating success.
 124
 125    Hardware simulator: Normally, each program section is written into
 126    memory according to that sections LMA using physical (direct)
 127    addressing.  The exception being systems, such as PPC/CHRP, which
 128    support more complicated program loaders.  A call to this function
 129    should not effect the state of the processor registers.  Multiple
 130    calls to this function are permitted and have an accumulative
 131    effect.
 132
 133    Process simulator: Calls to this function may be ignored.
 134
 135    FIXME: Most hardware simulators load the image at the VMA using
 136    virtual addressing.
 137
 138    FIXME: For some hardware targets, before a loaded program can be
 139    executed, it requires the manipulation of VM registers and tables.
 140    Such manipulation should probably (?) occure in
 141    sim_create_inferior. */
 142
 143 SIM_RC sim_load (SIM_DESC sd, const char *prog, struct bfd *abfd, int from_tty);
 144
 145
 146 /* Prepare to run the simulated program.
 147
 148    ABFD, if not NULL, provides initial processor state information.
 149    ARGV and ENV, if non NULL, are NULL terminated lists of pointers.
 150
 151    Hardware simulator: This function shall initialize the processor
 152    registers to a known value.  The program counter and possibly stack
 153    pointer shall be set using information obtained from ABFD (or
 154    hardware reset defaults).  ARGV and ENV, dependant on the target
 155    ABI, may be written to memory.
 156
 157    Process simulator: After a call to this function, a new process
 158    instance shall exist. The TEXT, DATA, BSS and stack regions shall
 159    all be initialized, ARGV and ENV shall be written to process
 160    address space (according to the applicable ABI) and the program
 161    counter and stack pointer set accordingly. */
 162
 163 SIM_RC sim_create_inferior (SIM_DESC sd, struct bfd *abfd, char **argv, char **env);
 164
 165
 166 /* Fetch LENGTH bytes of the simulated program's memory.  Start fetch
 167    at virtual address MEM and store in BUF.  Result is number of bytes
 168    read, or zero if error.  */
 169
 170 int sim_read (SIM_DESC sd, SIM_ADDR mem, unsigned char *buf, int length);
 171
 172
 173 /* Store LENGTH bytes from BUF into the simulated program's
 174    memory. Store bytes starting at virtual address MEM. Result is
 175    number of bytes write, or zero if error.  */
 176
 177 int sim_write (SIM_DESC sd, SIM_ADDR mem, const unsigned char *buf, int length);
 178
 179
 180 /* Fetch register REGNO storing its raw (target endian) value in the
 181    LENGTH byte buffer BUF.  Return the actual size of the register or
 182    zero if REGNO is not applicable.
 183
 184    Legacy implementations ignore LENGTH and always return -1.
 185
 186    If LENGTH does not match the size of REGNO no data is transfered
 187    (the actual register size is still returned). */
 188
 189 int sim_fetch_register (SIM_DESC sd, int regno, unsigned char *buf, int length);
 190
 191
 192 /* Store register REGNO from the raw (target endian) value in BUF.
 193
 194    Return the actual size of the register, any size not equal to
 195    LENGTH indicates the register was not updated correctly.
 196
 197    Return a LENGTH of -1 to indicate the register was not updated
 198    and an error has occurred.
 199
 200    Return a LENGTH of 0 to indicate the register was not updated
 201    but no error has occurred. */
 202
 203 int sim_store_register (SIM_DESC sd, int regno, unsigned char *buf, int length);
 204
 205
 206 /* Print whatever statistics the simulator has collected.
 207
 208    VERBOSE is currently unused and must always be zero.  */
 209
 210 void sim_info (SIM_DESC sd, int verbose);
 211
 212
 213 /* Run (or resume) the simulated program.
 214
 215    STEP, when non-zero indicates that only a single simulator cycle
 216    should be emulated.
 217
 218    SIGGNAL, if non-zero is a (HOST) SIGRC value indicating the type of
 219    event (hardware interrupt, signal) to be delivered to the simulated
 220    program.
 221
 222    Hardware simulator: If the SIGRC value returned by
 223    sim_stop_reason() is passed back to the simulator via SIGGNAL then
 224    the hardware simulator shall correctly deliver the hardware event
 225    indicated by that signal.  If a value of zero is passed in then the
 226    simulation will continue as if there were no outstanding signal.
 227    The effect of any other SIGGNAL value is is implementation
 228    dependant.
 229
 230    Process simulator: If SIGRC is non-zero then the corresponding
 231    signal is delivered to the simulated program and execution is then
 232    continued.  A zero SIGRC value indicates that the program should
 233    continue as normal. */
 234
 235 void sim_resume (SIM_DESC sd, int step, int siggnal);
 236
 237
 238 /* Asynchronous request to stop the simulation.
 239    A nonzero return indicates that the simulator is able to handle
 240    the request */
 241
 242 int sim_stop (SIM_DESC sd);
 243
 244
 245 /* Fetch the REASON why the program stopped.
 246
 247    SIM_EXITED: The program has terminated. SIGRC indicates the target
 248    dependant exit status.
 249
 250    SIM_STOPPED: The program has stopped.  SIGRC uses the host's signal
 251    numbering as a way of identifying the reaon: program interrupted by
 252    user via a sim_stop request (SIGINT); a breakpoint instruction
 253    (SIGTRAP); a completed single step (SIGTRAP); an internal error
 254    condition (SIGABRT); an illegal instruction (SIGILL); Access to an
 255    undefined memory region (SIGSEGV); Mis-aligned memory access
 256    (SIGBUS).  For some signals information in addition to the signal
 257    number may be retained by the simulator (e.g. offending address),
 258    that information is not directly accessable via this interface.
 259
 260    SIM_SIGNALLED: The program has been terminated by a signal. The
 261    simulator has encountered target code that causes the the program
 262    to exit with signal SIGRC.
 263
 264    SIM_RUNNING, SIM_POLLING: The return of one of these values
 265    indicates a problem internal to the simulator. */
 266
 267 enum sim_stop { sim_running, sim_polling, sim_exited, sim_stopped, sim_signalled };
 268
 269 void sim_stop_reason (SIM_DESC sd, enum sim_stop *reason, int *sigrc);
 270
 271
 272 /* Passthru for other commands that the simulator might support.
 273    Simulators should be prepared to deal with any combination of NULL
 274    or empty CMD. */
 275
 276 void sim_do_command (SIM_DESC sd, char *cmd);
 277
 278 /* Complete a command based on the available sim commands.  Returns an
 279    array of possible matches.  */
 280
 281 char **sim_complete_command (SIM_DESC sd, const char *text, const char *word);
 282
 283 #ifdef __cplusplus
 284 }
 285 #endif
 286
 287 #endif /* !defined (REMOTE_SIM_H) */