/* Target operations for the remote server for GDB.
   Copyright 2002
   Free Software Foundation, Inc.

   Contributed by MontaVista Software.

   This file is part of GDB.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 59 Temple Place - Suite 330,
   Boston, MA 02111-1307, USA.  */

#ifndef TARGET_H
#define TARGET_H

/* This structure describes how to resume a particular thread (or
   all threads) based on the client's request.  If thread is -1, then
   this entry applies to all threads.  These are generally passed around
   as an array, and terminated by a thread == -1 entry.  */

struct thread_resume
{
  int thread;

  /* If non-zero, leave this thread stopped.  */
  int leave_stopped;

  /* If non-zero, we want to single-step.  */
  int step;

  /* If non-zero, send this signal when we resume.  */
  int sig;
};

struct target_ops
{
  /* Start a new process.

     PROGRAM is a path to the program to execute.
     ARGS is a standard NULL-terminated array of arguments,
     to be passed to the inferior as ``argv''.

     Returns the new PID on success, -1 on failure.  Registers the new
     process with the process list.  */

  int (*create_inferior) (char *program, char **args);

  /* Attach to a running process.

     PID is the process ID to attach to, specified by the user
     or a higher layer.  */

  int (*attach) (int pid);

  /* Kill all inferiors.  */

  void (*kill) (void);

  /* Detach from all inferiors.  */

  void (*detach) (void);

  /* Return 1 iff the thread with process ID PID is alive.  */

  int (*thread_alive) (int pid);

  /* Resume the inferior process.  */

  void (*resume) (struct thread_resume *resume_info);

  /* Wait for the inferior process to change state.

     STATUSP will be filled in with a response code to send to GDB.

     Returns the signal which caused the process to stop.  */

  unsigned char (*wait) (char *status);

  /* Fetch registers from the inferior process.

     If REGNO is -1, fetch all registers; otherwise, fetch at least REGNO.  */

  void (*fetch_registers) (int regno);
  
  /* Store registers to the inferior process.

     If REGNO is -1, store all registers; otherwise, store at least REGNO.  */

  void (*store_registers) (int regno);

  /* Read memory from the inferior process.  This should generally be
     called through read_inferior_memory, which handles breakpoint shadowing.

     Read LEN bytes at MEMADDR into a buffer at MYADDR.  */

  void (*read_memory) (CORE_ADDR memaddr, char *myaddr, int len);

  /* Write memory to the inferior process.  This should generally be
     called through write_inferior_memory, which handles breakpoint shadowing.

     Write LEN bytes from the buffer at MYADDR to MEMADDR.

     Returns 0 on success and errno on failure.  */

  int (*write_memory) (CORE_ADDR memaddr, const char *myaddr, int len);

  /* Query GDB for the values of any symbols we're interested in.
     This function is called whenever we receive a "qSymbols::"
     query, which corresponds to every time more symbols (might)
     become available.  NULL if we aren't interested in any
     symbols.  */

  void (*look_up_symbols) (void);

  /* Send a signal to the inferior process, however is appropriate.  */
  void (*send_signal) (int);
};

extern struct target_ops *the_target;

void set_target_ops (struct target_ops *);

#define create_inferior(program, args) \
  (*the_target->create_inferior) (program, args)

#define myattach(pid) \
  (*the_target->attach) (pid)

#define kill_inferior() \
  (*the_target->kill) ()

#define detach_inferior() \
  (*the_target->detach) ()

#define mythread_alive(pid) \
  (*the_target->thread_alive) (pid)

#define fetch_inferior_registers(regno) \
  (*the_target->fetch_registers) (regno)

#define store_inferior_registers(regno) \
  (*the_target->store_registers) (regno)

unsigned char mywait (char *statusp, int connected_wait);

void read_inferior_memory (CORE_ADDR memaddr, char *myaddr, int len);

int write_inferior_memory (CORE_ADDR memaddr, const char *myaddr, int len);

void set_desired_inferior (int id);

#endif /* TARGET_H */