[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

/* Forward decl for stat/fstat.  */
struct stat;

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 *));
  int (*stat) PARAMS ((host_callback *, const char *, struct stat *));
  int (*fstat) PARAMS ((host_callback *, int, struct stat *));

  /* 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.
   ??? One can certainly start a discussion over the ones that are currently
   here, but that will always be true.  */

/* These are used by the ANSI C support of libc.  */
#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	14
#define CB_SYS_stat	15
#define CB_SYS_chmod 	16
#define CB_SYS_utime 	17
#define CB_SYS_time 	18
\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.  */
  PTR p1;
  PTR p2;
  long x1,x2;

  /* Callbacks for reading/writing memory (e.g. for read/write syscalls).
     ??? long or unsigned long might be better to use for the `count'
     argument here.  We mimic sim_{read,write} for now.  Be careful to
     test any changes with -Wall -Werror, mixed signed comparisons
     will get you.  */
  int (*read_mem) PARAMS ((host_callback * /*cb*/, struct cb_syscall * /*sc*/,
			   unsigned long /*taddr*/, char * /*buf*/,
			   int /*bytes*/));
  int (*write_mem) PARAMS ((host_callback * /*cb*/, struct cb_syscall * /*sc*/,
			    unsigned long /*taddr*/, const char * /*buf*/,
			    int /*bytes*/));

  /* For sanity checking, should be last entry.  */
  int magic;
} CB_SYSCALL;

/* Magic number sanity checker.  */
#define CB_SYSCALL_MAGIC 0x12344321

/* Macro to initialize CB_SYSCALL.  Called first, before filling in
   any fields.  */
#define CB_SYSCALL_INIT(sc) \
do { \
  memset ((sc), 0, sizeof (*(sc))); \
  (sc)->magic = CB_SYSCALL_MAGIC; \
} while (0)
\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.
   If stat struct ptr is NULL, just compute target stat struct size.
   Result is size of target stat struct or 0 if error.  */
int cb_host_to_target_stat PARAMS ((host_callback *, const struct stat *, PTR));

/* 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
7de19d31 DE	71	/* Forward decl for stat/fstat. */
	72	struct stat;
	73
8d5306e7 DE	74	typedef struct host_callback_struct host_callback;
8d5306e7 DE	75
9d10b92d DE	76	struct host_callback_struct
	77	{
	78	int (close) PARAMS ((host_callback ,int));
	79	int (get_errno) PARAMS ((host_callback ));
	80	int (isatty) PARAMS ((host_callback , int));
	81	int (lseek) PARAMS ((host_callback , int, long , int));
	82	int (open) PARAMS ((host_callback , const char*, int mode));
	83	int (read) PARAMS ((host_callback ,int, char *, int));
	84	int (read_stdin) PARAMS (( host_callback , char *, int));
	85	int (rename) PARAMS ((host_callback , const char , const char ));
	86	int (system) PARAMS ((host_callback , const char *));
	87	long (time) PARAMS ((host_callback , long *));
	88	int (unlink) PARAMS ((host_callback , const char *));
	89	int (write) PARAMS ((host_callback ,int, const char *, int));
	90	int (write_stdout) PARAMS ((host_callback , const char *, int));
6d685937 AC	91	void (flush_stdout) PARAMS ((host_callback ));
	92	int (write_stderr) PARAMS ((host_callback , const char *, int));
	93	void (flush_stderr) PARAMS ((host_callback ));
7de19d31 DE	94	int (stat) PARAMS ((host_callback , const char , struct stat ));
7de19d31 DE	95	int (fstat) PARAMS ((host_callback , int, struct stat *));
9d10b92d	96
8517f62b AC	97	/* When present, call to the client to give it the oportunity to
	98	poll any io devices for a request to quit (indicated by a nonzero
	99	return value). */
	100	int (poll_quit) PARAMS ((host_callback ));
	101
9d10b92d	102	/* Used when the target has gone away, so we can close open
e1144153	103	handles and free memory etc etc. */
9d10b92d DE	104	int (shutdown) PARAMS ((host_callback ));
	105	int (init) PARAMS ((host_callback ));
	106
6d685937	107	/* depreciated, use vprintf_filtered - Talk to the user on a console. */
9d10b92d	108	void (printf_filtered) PARAMS ((host_callback , const char *, ...));
6d685937	109
09e34873	110	/* Talk to the user on a console. */
8902803f	111	void (vprintf_filtered) PARAMS ((host_callback , const char *, va_list));
6d685937	112
efa86080	113	/* Same as vprintf_filtered but to stderr. */
8902803f	114	void (evprintf_filtered) PARAMS ((host_callback , const char *, va_list));
efa86080	115
e1144153 DE	116	/* Print an error message and "exit".
	117	In the case of gdb "exiting" means doing a longjmp back to the main
	118	command loop. */
	119	void (error) PARAMS ((host_callback , const char *, ...));
9d10b92d DE	120
	121	int last_errno; /* host format */
	122
	123	int fdmap[MAX_CALLBACK_FDS];
	124	char fdopen[MAX_CALLBACK_FDS];
	125	char alwaysopen[MAX_CALLBACK_FDS];
8517f62b	126
8d5306e7 DE	127	/* System call numbers. */
	128	CB_TARGET_DEFS_MAP *syscall_map;
	129	/* Errno values. */
	130	CB_TARGET_DEFS_MAP *errno_map;
	131	/* Flags to the open system call. */
	132	CB_TARGET_DEFS_MAP *open_map;
	133	/* Signal numbers. */
	134	CB_TARGET_DEFS_MAP *signal_map;
	135	/* Layout of `stat' struct.
	136	The format is a series of "name,length" pairs separated by colons.
	137	Empty space is indicated with a `name' of "space".
	138	All padding must be explicitly mentioned.
	139	Lengths are in bytes. If this needs to be extended to bits,
	140	use "name.bits".
	141	Example: "st_dev,4:st_ino,4:st_mode,4:..." */
	142	const char *stat_map;
	143
	144	/* Marker for those wanting to do sanity checks.
	145	This should remain the last member of this struct to help catch
8517f62b AC	146	miscompilation errors. */
	147	#define HOST_CALLBACK_MAGIC 4705 /* teds constant */
	148	int magic;
9d10b92d DE	149	};
	150
	151	extern host_callback default_callback;
8d5306e7 DE	152	\f
	153	/* Canonical versions of system call numbers.
	154	It's not intended to willy-nilly throw every system call ever heard
7de19d31 DE	155	of in here. Only include those that have an important use.
	156	??? One can certainly start a discussion over the ones that are currently
	157	here, but that will always be true. */
8d5306e7	158
7de19d31	159	/* These are used by the ANSI C support of libc. */
8d5306e7 DE	160	#define CB_SYS_exit 1
	161	#define CB_SYS_open 2
	162	#define CB_SYS_close 3
	163	#define CB_SYS_read 4
	164	#define CB_SYS_write 5
	165	#define CB_SYS_lseek 6
	166	#define CB_SYS_unlink 7
	167	#define CB_SYS_getpid 8
	168	#define CB_SYS_kill 9
7de19d31	169	#define CB_SYS_fstat 10
8d5306e7 DE	170	/#define CB_SYS_sbrk 11 - not currently a system call, but reserved. /
	171
	172	/* ARGV support. */
	173	#define CB_SYS_argvlen 12
	174	#define CB_SYS_argv 13
	175
	176	/* These are extras added for one reason or another. */
7de19d31 DE	177	#define CB_SYS_chdir 14
	178	#define CB_SYS_stat 15
	179	#define CB_SYS_chmod 16
	180	#define CB_SYS_utime 17
	181	#define CB_SYS_time 18
8d5306e7 DE	182	\f
	183	/* Struct use to pass and return information necessary to perform a
	184	system call. */
	185	/* FIXME: Need to consider target word size. */
	186
	187	typedef struct cb_syscall {
	188	/* The target's value of what system call to perform. */
	189	int func;
	190	/* The arguments to the syscall. */
	191	long arg1, arg2, arg3, arg4;
	192
	193	/* The result. */
	194	long result;
	195	/* Some system calls have two results. */
	196	long result2;
	197	/* The target's errno value, or 0 if success.
	198	This is converted to the target's value with host_to_target_errno. */
	199	int errcode;
	200
	201	/* Working space to be used by memory read/write callbacks. */
7de19d31 DE	202	PTR p1;
7de19d31 DE	203	PTR p2;
8d5306e7 DE	204	long x1,x2;
8d5306e7 DE	205
881a6011 DE	206	/* Callbacks for reading/writing memory (e.g. for read/write syscalls).
	207	??? long or unsigned long might be better to use for the `count'
	208	argument here. We mimic sim_{read,write} for now. Be careful to
	209	test any changes with -Wall -Werror, mixed signed comparisons
	210	will get you. */
1e92854b DE	211	int (read_mem) PARAMS ((host_callback /cb/, struct cb_syscall * /sc/,
	212	unsigned long /taddr/, char * /buf/,
	213	int /bytes/));
	214	int (write_mem) PARAMS ((host_callback /cb/, struct cb_syscall * /sc/,
	215	unsigned long /taddr/, const char * /buf/,
	216	int /bytes/));
881a6011 DE	217
	218	/* For sanity checking, should be last entry. */
	219	int magic;
8d5306e7	220	} CB_SYSCALL;
881a6011 DE	221
	222	/* Magic number sanity checker. */
	223	#define CB_SYSCALL_MAGIC 0x12344321
	224
	225	/* Macro to initialize CB_SYSCALL. Called first, before filling in
	226	any fields. */
	227	#define CB_SYSCALL_INIT(sc) \
	228	do { \
	229	memset ((sc), 0, sizeof (*(sc))); \
	230	(sc)->magic = CB_SYSCALL_MAGIC; \
	231	} while (0)
8d5306e7 DE	232	\f
	233	/* Return codes for various interface routines. */
	234
	235	typedef enum {
	236	CB_RC_OK = 0,
	237	/* generic error */
	238	CB_RC_ERR,
	239	/* either file not found or no read access */
	240	CB_RC_ACCESS,
	241	CB_RC_NO_MEM
	242	} CB_RC;
	243
	244	/* Read in target values for system call numbers, errno values, signals. */
	245	CB_RC cb_read_target_syscall_maps PARAMS ((host_callback , const char ));
	246
	247	/* Translate target to host syscall function numbers. */
	248	int cb_target_to_host_syscall PARAMS ((host_callback *, int));
	249
	250	/* Translate host to target errno value. */
	251	int cb_host_to_target_errno PARAMS ((host_callback *, int));
	252
	253	/* Translate target to host open flags. */
	254	int cb_target_to_host_open PARAMS ((host_callback *, int));
	255
	256	/* Translate target signal number to host. */
	257	int cb_target_to_host_signal PARAMS ((host_callback *, int));
	258
	259	/* Translate host signal number to target. */
	260	int cb_host_to_target_signal PARAMS ((host_callback *, int));
	261
7de19d31 DE	262	/* Translate host stat struct to target.
	263	If stat struct ptr is NULL, just compute target stat struct size.
	264	Result is size of target stat struct or 0 if error. */
	265	int cb_host_to_target_stat PARAMS ((host_callback , const struct stat , PTR));
8d5306e7 DE	266
	267	/* Perform a system call. */
	268	CB_RC cb_syscall PARAMS ((host_callback , CB_SYSCALL ));
9d10b92d DE	269
9d10b92d DE	270	#endif