[deliverable/binutils-gdb.git] / include / callback.h

/* Remote target system call callback support.
   Copyright 1997 Free Software Foundation, Inc.
   Contributed by Cygnus Solutions.

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.  */

/* This interface isn't intended to be specific to any particular kind
   of remote (hardware, simulator, whatever).  As such, support for it
   (e.g. sim/common/callback.c) should *not* live in the simulator source
   tree, nor should it live in the gdb source tree.  */

/* There are various ways to handle system calls:

   1) Have a simulator intercept the appropriate trap instruction and
   directly perform the system call on behalf of the target program.
   This is the typical way of handling system calls for embedded targets.
   [Handling system calls for embedded targets isn't that much of an
   oxymoron as running compiler testsuites make use of the capability.]

   This method of system call handling is done when STATE_ENVIRONMENT
   is ENVIRONMENT_USER.

   2) Have a simulator emulate the hardware as much as possible.
   If the program running on the real hardware communicates with some sort
   of target manager, one would want to be able to run this program on the
   simulator as well.

   This method of system call handling is done when STATE_ENVIRONMENT
   is ENVIRONMENT_OPERATING.
*/

#ifndef CALLBACK_H
#define CALLBACK_H

/* ??? The reason why we check for va_start here should be documented.  */

#ifndef va_start
#include <ansidecl.h>
#ifdef ANSI_PROTOTYPES
#include <stdarg.h>
#else
#include <varargs.h>
#endif
#endif
\f
/* Mapping of host/target values.  */
/* ??? For debugging purposes, one might want to add a string of the
   name of the symbol.  */

typedef struct {
  int host_val;
  int target_val;
} CB_TARGET_DEFS_MAP;

#define MAX_CALLBACK_FDS 10

typedef struct host_callback_struct host_callback;

struct host_callback_struct 
{
  int (*close) PARAMS ((host_callback *,int));
  int (*get_errno) PARAMS ((host_callback *));
  int (*isatty) PARAMS ((host_callback *, int));
  int (*lseek) PARAMS ((host_callback *, int, long , int));
  int (*open) PARAMS ((host_callback *, const char*, int mode));
  int (*read) PARAMS ((host_callback *,int,  char *, int));
  int (*read_stdin) PARAMS (( host_callback *, char *, int));
  int (*rename) PARAMS ((host_callback *, const char *, const char *));
  int (*system) PARAMS ((host_callback *, const char *));
  long (*time) PARAMS ((host_callback *, long *));
  int (*unlink) PARAMS ((host_callback *, const char *));
  int (*write) PARAMS ((host_callback *,int, const char *, int));
  int (*write_stdout) PARAMS ((host_callback *, const char *, int));
  void (*flush_stdout) PARAMS ((host_callback *));
  int (*write_stderr) PARAMS ((host_callback *, const char *, int));
  void (*flush_stderr) PARAMS ((host_callback *));
  /* PTR is not `struct stat' because the target's value is stored.  */
  int (*stat) PARAMS ((host_callback *, const char *, PTR));
  int (*fstat) PARAMS ((host_callback *, int, PTR));

  /* When present, call to the client to give it the oportunity to
     poll any io devices for a request to quit (indicated by a nonzero
     return value). */
  int (*poll_quit) PARAMS ((host_callback *));

  /* Used when the target has gone away, so we can close open
     handles and free memory etc etc.  */
  int (*shutdown) PARAMS ((host_callback *));
  int (*init)     PARAMS ((host_callback *));

  /* depreciated, use vprintf_filtered - Talk to the user on a console.  */
  void (*printf_filtered) PARAMS ((host_callback *, const char *, ...));

  /* Talk to the user on a console.  */
  void (*vprintf_filtered) PARAMS ((host_callback *, const char *, va_list));

  /* Same as vprintf_filtered but to stderr.  */
  void (*evprintf_filtered) PARAMS ((host_callback *, const char *, va_list));

  /* Print an error message and "exit".
     In the case of gdb "exiting" means doing a longjmp back to the main
     command loop.  */
  void (*error) PARAMS ((host_callback *, const char *, ...));

  int last_errno;		/* host format */

  int fdmap[MAX_CALLBACK_FDS];
  char fdopen[MAX_CALLBACK_FDS];
  char alwaysopen[MAX_CALLBACK_FDS];

  /* System call numbers.  */
  CB_TARGET_DEFS_MAP *syscall_map;
  /* Errno values.  */
  CB_TARGET_DEFS_MAP *errno_map;
  /* Flags to the open system call.  */
  CB_TARGET_DEFS_MAP *open_map;
  /* Signal numbers.  */
  CB_TARGET_DEFS_MAP *signal_map;
  /* Layout of `stat' struct.
     The format is a series of "name,length" pairs separated by colons.
     Empty space is indicated with a `name' of "space".
     All padding must be explicitly mentioned.
     Lengths are in bytes.  If this needs to be extended to bits,
     use "name.bits".
     Example: "st_dev,4:st_ino,4:st_mode,4:..."  */
  const char *stat_map;

  /* Marker for those wanting to do sanity checks.
     This should remain the last member of this struct to help catch
     miscompilation errors. */
#define HOST_CALLBACK_MAGIC 4705 /* teds constant */
  int magic;
};

extern host_callback default_callback;
\f
/* Canonical versions of system call numbers.
   It's not intended to willy-nilly throw every system call ever heard
   of in here.  Only include those that have an important use.  */

#define	CB_SYS_exit	1
#define	CB_SYS_open	2
#define	CB_SYS_close	3
#define	CB_SYS_read	4
#define	CB_SYS_write	5
#define	CB_SYS_lseek	6
#define	CB_SYS_unlink	7
#define	CB_SYS_getpid	8
#define	CB_SYS_kill	9
#define CB_SYS_fstat       10
/*#define CB_SYS_sbrk	11 - not currently a system call, but reserved.  */

/* ARGV support.  */
#define CB_SYS_argvlen	12
#define CB_SYS_argv	13

/* These are extras added for one reason or another.  */
#define CB_SYS_chdir	20
#define CB_SYS_stat	21
#define CB_SYS_chmod 	22
#define CB_SYS_utime 	23
#define CB_SYS_time 	24
\f
/* Struct use to pass and return information necessary to perform a
   system call.  */
/* FIXME: Need to consider target word size.  */

typedef struct cb_syscall {
  /* The target's value of what system call to perform.  */
  int func;
  /* The arguments to the syscall.  */
  long arg1, arg2, arg3, arg4;

  /* The result.  */
  long result;
  /* Some system calls have two results.  */
  long result2;
  /* The target's errno value, or 0 if success.
     This is converted to the target's value with host_to_target_errno.  */
  int errcode;

  /* Working space to be used by memory read/write callbacks.  */
  long x1,x2;

  /* Callbacks for reading/writing memory (e.g. for read/write syscalls).  */
  unsigned long (*read_mem) PARAMS ((host_callback *, struct cb_syscall *, unsigned long taddr, char *buf, unsigned long bytes));
  unsigned long (*write_mem) PARAMS ((host_callback *, struct cb_syscall *, unsigned long taddr, const char *buf, unsigned long bytes));
} CB_SYSCALL;
\f
/* Return codes for various interface routines.  */

typedef enum {
  CB_RC_OK = 0,
  /* generic error */
  CB_RC_ERR,
  /* either file not found or no read access */
  CB_RC_ACCESS,
  CB_RC_NO_MEM
} CB_RC;

/* Read in target values for system call numbers, errno values, signals.  */
CB_RC cb_read_target_syscall_maps PARAMS ((host_callback *, const char *));

/* Translate target to host syscall function numbers.  */
int cb_target_to_host_syscall PARAMS ((host_callback *, int));

/* Translate host to target errno value.  */
int cb_host_to_target_errno PARAMS ((host_callback *, int));

/* Translate target to host open flags.  */
int cb_target_to_host_open PARAMS ((host_callback *, int));

/* Translate target signal number to host.  */
int cb_target_to_host_signal PARAMS ((host_callback *, int));

/* Translate host signal number to target.  */
int cb_host_to_target_signal PARAMS ((host_callback *, int));

/* Translate host stat struct to target.  */
struct stat; /* forward decl */
int cb_host_to_target_stat PARAMS ((host_callback *, const struct stat *,
				    PTR, int));

/* Perform a system call.  */
CB_RC cb_syscall PARAMS ((host_callback *, CB_SYSCALL *));

#endif
Commit	Line	Data
efa86080 DE	1	/* Remote target system call callback support.
efa86080 DE	2	Copyright 1997 Free Software Foundation, Inc.
8d5306e7	3	Contributed by Cygnus Solutions.
efa86080 DE	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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
	20
8d5306e7 DE	21	/* This interface isn't intended to be specific to any particular kind
	22	of remote (hardware, simulator, whatever). As such, support for it
	23	(e.g. sim/common/callback.c) should not live in the simulator source
	24	tree, nor should it live in the gdb source tree. */
	25
	26	/* There are various ways to handle system calls:
	27
	28	1) Have a simulator intercept the appropriate trap instruction and
	29	directly perform the system call on behalf of the target program.
	30	This is the typical way of handling system calls for embedded targets.
	31	[Handling system calls for embedded targets isn't that much of an
	32	oxymoron as running compiler testsuites make use of the capability.]
	33
	34	This method of system call handling is done when STATE_ENVIRONMENT
	35	is ENVIRONMENT_USER.
	36
	37	2) Have a simulator emulate the hardware as much as possible.
	38	If the program running on the real hardware communicates with some sort
	39	of target manager, one would want to be able to run this program on the
	40	simulator as well.
	41
	42	This method of system call handling is done when STATE_ENVIRONMENT
	43	is ENVIRONMENT_OPERATING.
	44	*/
bf008f98	45
9d10b92d DE	46	#ifndef CALLBACK_H
	47	#define CALLBACK_H
	48
8d5306e7 DE	49	/* ??? The reason why we check for va_start here should be documented. */
8d5306e7 DE	50
8902803f MM	51	#ifndef va_start
	52	#include <ansidecl.h>
	53	#ifdef ANSI_PROTOTYPES
	54	#include <stdarg.h>
	55	#else
	56	#include <varargs.h>
	57	#endif
	58	#endif
8d5306e7 DE	59	\f
	60	/* Mapping of host/target values. */
	61	/* ??? For debugging purposes, one might want to add a string of the
	62	name of the symbol. */
8902803f	63
8d5306e7 DE	64	typedef struct {
	65	int host_val;
	66	int target_val;
	67	} CB_TARGET_DEFS_MAP;
9d10b92d DE	68
	69	#define MAX_CALLBACK_FDS 10
	70
8d5306e7 DE	71	typedef struct host_callback_struct host_callback;
8d5306e7 DE	72
9d10b92d DE	73	struct host_callback_struct
	74	{
	75	int (close) PARAMS ((host_callback ,int));
	76	int (get_errno) PARAMS ((host_callback ));
	77	int (isatty) PARAMS ((host_callback , int));
	78	int (lseek) PARAMS ((host_callback , int, long , int));
	79	int (open) PARAMS ((host_callback , const char*, int mode));
	80	int (read) PARAMS ((host_callback ,int, char *, int));
	81	int (read_stdin) PARAMS (( host_callback , char *, int));
	82	int (rename) PARAMS ((host_callback , const char , const char ));
	83	int (system) PARAMS ((host_callback , const char *));
	84	long (time) PARAMS ((host_callback , long *));
	85	int (unlink) PARAMS ((host_callback , const char *));
	86	int (write) PARAMS ((host_callback ,int, const char *, int));
	87	int (write_stdout) PARAMS ((host_callback , const char *, int));
6d685937 AC	88	void (flush_stdout) PARAMS ((host_callback ));
	89	int (write_stderr) PARAMS ((host_callback , const char *, int));
	90	void (flush_stderr) PARAMS ((host_callback ));
8d5306e7 DE	91	/* PTR is not `struct stat' because the target's value is stored. */
	92	int (stat) PARAMS ((host_callback , const char *, PTR));
	93	int (fstat) PARAMS ((host_callback , int, PTR));
9d10b92d	94
8517f62b AC	95	/* When present, call to the client to give it the oportunity to
	96	poll any io devices for a request to quit (indicated by a nonzero
	97	return value). */
	98	int (poll_quit) PARAMS ((host_callback ));
	99
9d10b92d	100	/* Used when the target has gone away, so we can close open
e1144153	101	handles and free memory etc etc. */
9d10b92d DE	102	int (shutdown) PARAMS ((host_callback ));
	103	int (init) PARAMS ((host_callback ));
	104
6d685937	105	/* depreciated, use vprintf_filtered - Talk to the user on a console. */
9d10b92d	106	void (printf_filtered) PARAMS ((host_callback , const char *, ...));
6d685937	107
09e34873	108	/* Talk to the user on a console. */
8902803f	109	void (vprintf_filtered) PARAMS ((host_callback , const char *, va_list));
6d685937	110
efa86080	111	/* Same as vprintf_filtered but to stderr. */
8902803f	112	void (evprintf_filtered) PARAMS ((host_callback , const char *, va_list));
efa86080	113
e1144153 DE	114	/* Print an error message and "exit".
	115	In the case of gdb "exiting" means doing a longjmp back to the main
	116	command loop. */
	117	void (error) PARAMS ((host_callback , const char *, ...));
9d10b92d DE	118
	119	int last_errno; /* host format */
	120
	121	int fdmap[MAX_CALLBACK_FDS];
	122	char fdopen[MAX_CALLBACK_FDS];
	123	char alwaysopen[MAX_CALLBACK_FDS];
8517f62b	124
8d5306e7 DE	125	/* System call numbers. */
	126	CB_TARGET_DEFS_MAP *syscall_map;
	127	/* Errno values. */
	128	CB_TARGET_DEFS_MAP *errno_map;
	129	/* Flags to the open system call. */
	130	CB_TARGET_DEFS_MAP *open_map;
	131	/* Signal numbers. */
	132	CB_TARGET_DEFS_MAP *signal_map;
	133	/* Layout of `stat' struct.
	134	The format is a series of "name,length" pairs separated by colons.
	135	Empty space is indicated with a `name' of "space".
	136	All padding must be explicitly mentioned.
	137	Lengths are in bytes. If this needs to be extended to bits,
	138	use "name.bits".
	139	Example: "st_dev,4:st_ino,4:st_mode,4:..." */
	140	const char *stat_map;
	141
	142	/* Marker for those wanting to do sanity checks.
	143	This should remain the last member of this struct to help catch
8517f62b AC	144	miscompilation errors. */
	145	#define HOST_CALLBACK_MAGIC 4705 /* teds constant */
	146	int magic;
9d10b92d DE	147	};
	148
	149	extern host_callback default_callback;
8d5306e7 DE	150	\f
	151	/* Canonical versions of system call numbers.
	152	It's not intended to willy-nilly throw every system call ever heard
	153	of in here. Only include those that have an important use. */
	154
	155	#define CB_SYS_exit 1
	156	#define CB_SYS_open 2
	157	#define CB_SYS_close 3
	158	#define CB_SYS_read 4
	159	#define CB_SYS_write 5
	160	#define CB_SYS_lseek 6
	161	#define CB_SYS_unlink 7
	162	#define CB_SYS_getpid 8
	163	#define CB_SYS_kill 9
	164	#define CB_SYS_fstat 10
	165	/#define CB_SYS_sbrk 11 - not currently a system call, but reserved. /
	166
	167	/* ARGV support. */
	168	#define CB_SYS_argvlen 12
	169	#define CB_SYS_argv 13
	170
	171	/* These are extras added for one reason or another. */
	172	#define CB_SYS_chdir 20
	173	#define CB_SYS_stat 21
	174	#define CB_SYS_chmod 22
	175	#define CB_SYS_utime 23
	176	#define CB_SYS_time 24
	177	\f
	178	/* Struct use to pass and return information necessary to perform a
	179	system call. */
	180	/* FIXME: Need to consider target word size. */
	181
	182	typedef struct cb_syscall {
	183	/* The target's value of what system call to perform. */
	184	int func;
	185	/* The arguments to the syscall. */
	186	long arg1, arg2, arg3, arg4;
	187
	188	/* The result. */
	189	long result;
	190	/* Some system calls have two results. */
	191	long result2;
	192	/* The target's errno value, or 0 if success.
	193	This is converted to the target's value with host_to_target_errno. */
	194	int errcode;
	195
	196	/* Working space to be used by memory read/write callbacks. */
	197	long x1,x2;
	198
	199	/* Callbacks for reading/writing memory (e.g. for read/write syscalls). */
	200	unsigned long (read_mem) PARAMS ((host_callback , struct cb_syscall , unsigned long taddr, char buf, unsigned long bytes));
	201	unsigned long (write_mem) PARAMS ((host_callback , struct cb_syscall , unsigned long taddr, const char buf, unsigned long bytes));
	202	} CB_SYSCALL;
	203	\f
	204	/* Return codes for various interface routines. */
	205
	206	typedef enum {
	207	CB_RC_OK = 0,
	208	/* generic error */
	209	CB_RC_ERR,
	210	/* either file not found or no read access */
	211	CB_RC_ACCESS,
	212	CB_RC_NO_MEM
	213	} CB_RC;
214
215	/* Read in target values for system call numbers, errno values, signals. */
216	CB_RC cb_read_target_syscall_maps PARAMS ((host_callback , const char ));
217
218	/* Translate target to host syscall function numbers. */
219	int cb_target_to_host_syscall PARAMS ((host_callback *, int));
220
221	/* Translate host to target errno value. */
222	int cb_host_to_target_errno PARAMS ((host_callback *, int));
223
224	/* Translate target to host open flags. */
225	int cb_target_to_host_open PARAMS ((host_callback *, int));
226
227	/* Translate target signal number to host. */
228	int cb_target_to_host_signal PARAMS ((host_callback *, int));
229
230	/* Translate host signal number to target. */
231	int cb_host_to_target_signal PARAMS ((host_callback *, int));
232
233	/* Translate host stat struct to target. */
234	struct stat; /* forward decl */
235	int cb_host_to_target_stat PARAMS ((host_callback , const struct stat ,
236	PTR, int));
237
238	/* Perform a system call. */
239	CB_RC cb_syscall PARAMS ((host_callback , CB_SYSCALL ));
9d10b92d DE	240
9d10b92d DE	241	#endif