1185 lines
27 KiB
C
1185 lines
27 KiB
C
/* Remote target communications for serial-line targets in custom GDB protocol
|
||
Copyright 1988, 1991, 1992, 1993 Free Software Foundation, Inc.
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||
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This file is part of GDB.
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This program is free software; you can redistribute it and/or modify
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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.
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||
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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||
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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||
GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program; if not, write to the Free Software
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Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
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/* Remote communication protocol.
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||
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A debug packet whose contents are <data>
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is encapsulated for transmission in the form:
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$ <data> # CSUM1 CSUM2
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||
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<data> must be ASCII alphanumeric and cannot include characters
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||
'$' or '#'
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||
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CSUM1 and CSUM2 are ascii hex representation of an 8-bit
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checksum of <data>, the most significant nibble is sent first.
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the hex digits 0-9,a-f are used.
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Receiver responds with:
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+ - if CSUM is correct and ready for next packet
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- - if CSUM is incorrect
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<data> is as follows:
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All values are encoded in ascii hex digits.
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Request Packet
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||
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read registers g
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reply XX....X Each byte of register data
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||
is described by two hex digits.
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Registers are in the internal order
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for GDB, and the bytes in a register
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are in the same order the machine uses.
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or ENN for an error.
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||
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write regs GXX..XX Each byte of register data
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is described by two hex digits.
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reply OK for success
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ENN for an error
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read mem mAA..AA,LLLL AA..AA is address, LLLL is length.
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reply XX..XX XX..XX is mem contents
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or ENN NN is errno
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write mem MAA..AA,LLLL:XX..XX
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AA..AA is address,
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||
LLLL is number of bytes,
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XX..XX is data
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||
reply OK for success
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ENN for an error
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cont cAA..AA AA..AA is address to resume
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If AA..AA is omitted,
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resume at same address.
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step sAA..AA AA..AA is address to resume
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If AA..AA is omitted,
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resume at same address.
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last signal ? Reply the current reason for stopping.
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This is the same reply as is generated
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for step or cont : SAA where AA is the
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signal number.
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There is no immediate reply to step or cont.
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The reply comes when the machine stops.
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It is SAA AA is the "signal number"
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or... TAAn...:r...;n:r...;n...:r...;
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AA = signal number
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n... = register number
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r... = register contents
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kill req k
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*/
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#include "defs.h"
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#include <string.h>
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#include <fcntl.h>
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#include "frame.h"
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#include "inferior.h"
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#include "bfd.h"
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#include "symfile.h"
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#include "target.h"
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#include "wait.h"
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#include "terminal.h"
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#include "gdbcmd.h"
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#if !defined(DONT_USE_REMOTE)
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#ifdef USG
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#include <sys/types.h>
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#endif
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#include <signal.h>
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#include "serial.h"
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/* Prototypes for local functions */
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static void
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remote_write_bytes PARAMS ((CORE_ADDR memaddr, char *myaddr, int len));
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static void
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remote_read_bytes PARAMS ((CORE_ADDR memaddr, char *myaddr, int len));
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static void
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remote_files_info PARAMS ((struct target_ops *ignore));
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static int
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remote_xfer_memory PARAMS ((CORE_ADDR memaddr, char *myaddr, int len,
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int should_write, struct target_ops *target));
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static void
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remote_prepare_to_store PARAMS ((void));
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static void
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remote_fetch_registers PARAMS ((int regno));
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static void
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remote_resume PARAMS ((int step, int siggnal));
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static int
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remote_start_remote PARAMS ((char *dummy));
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static void
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remote_open PARAMS ((char *name, int from_tty));
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static void
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remote_close PARAMS ((int quitting));
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static void
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remote_store_registers PARAMS ((int regno));
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static void
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getpkt PARAMS ((char *buf, int forever));
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static void
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putpkt PARAMS ((char *buf));
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static void
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remote_send PARAMS ((char *buf));
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static int
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readchar PARAMS ((void));
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static int
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remote_wait PARAMS ((WAITTYPE *status));
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static int
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tohex PARAMS ((int nib));
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static int
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fromhex PARAMS ((int a));
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static void
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remote_detach PARAMS ((char *args, int from_tty));
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static void
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remote_interrupt PARAMS ((int signo));
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static void
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remote_interrupt_twice PARAMS ((int signo));
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extern struct target_ops remote_ops; /* Forward decl */
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static int kiodebug = 0;
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/* This was 5 seconds, which is a long time to sit and wait.
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Unless this is going though some terminal server or multiplexer or
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other form of hairy serial connection, I would think 2 seconds would
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be plenty. */
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static int timeout = 2;
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#if 0
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int icache;
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#endif
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/* Descriptor for I/O to remote machine. Initialize it to NULL so that
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remote_open knows that we don't have a file open when the program
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starts. */
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serial_t remote_desc = NULL;
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#define PBUFSIZ 1024
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/* Maximum number of bytes to read/write at once. The value here
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is chosen to fill up a packet (the headers account for the 32). */
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#define MAXBUFBYTES ((PBUFSIZ-32)/2)
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/* Round up PBUFSIZ to hold all the registers, at least. */
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#if REGISTER_BYTES > MAXBUFBYTES
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#undef PBUFSIZ
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#define PBUFSIZ (REGISTER_BYTES * 2 + 32)
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#endif
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/* Clean up connection to a remote debugger. */
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/* ARGSUSED */
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static void
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remote_close (quitting)
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int quitting;
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{
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if (remote_desc)
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SERIAL_CLOSE (remote_desc);
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remote_desc = NULL;
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}
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/* Stub for catch_errors. */
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static int
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remote_start_remote (dummy)
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char *dummy;
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{
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/* Ack any packet which the remote side has already sent. */
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/* I'm not sure this \r is needed; we don't use it any other time we
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send an ack. */
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SERIAL_WRITE (remote_desc, "+\r", 2);
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putpkt ("?"); /* initiate a query from remote machine */
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start_remote (); /* Initialize gdb process mechanisms */
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return 1;
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}
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/* Open a connection to a remote debugger.
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NAME is the filename used for communication. */
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static void
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remote_open (name, from_tty)
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char *name;
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int from_tty;
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{
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if (name == 0)
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error (
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"To open a remote debug connection, you need to specify what serial\n\
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device is attached to the remote system (e.g. /dev/ttya).");
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target_preopen (from_tty);
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unpush_target (&remote_ops);
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#if 0
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dcache_init ();
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#endif
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remote_desc = SERIAL_OPEN (name);
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if (!remote_desc)
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perror_with_name (name);
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if (baud_rate)
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{
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int rate;
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if (sscanf (baud_rate, "%d", &rate) == 1)
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if (SERIAL_SETBAUDRATE (remote_desc, rate))
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{
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SERIAL_CLOSE (remote_desc);
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perror_with_name (name);
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}
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}
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SERIAL_RAW (remote_desc);
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if (from_tty)
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{
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puts_filtered ("Remote debugging using ");
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puts_filtered (name);
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puts_filtered ("\n");
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}
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push_target (&remote_ops); /* Switch to using remote target now */
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/* Start the remote connection; if error (0), discard this target. */
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immediate_quit++; /* Allow user to interrupt it */
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if (!catch_errors (remote_start_remote, (char *)0,
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"Couldn't establish connection to remote target\n", RETURN_MASK_ALL))
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pop_target();
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}
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/* remote_detach()
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takes a program previously attached to and detaches it.
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We better not have left any breakpoints
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in the program or it'll die when it hits one.
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Close the open connection to the remote debugger.
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Use this when you want to detach and do something else
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with your gdb. */
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static void
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remote_detach (args, from_tty)
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char *args;
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int from_tty;
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{
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if (args)
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error ("Argument given to \"detach\" when remotely debugging.");
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pop_target ();
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if (from_tty)
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puts_filtered ("Ending remote debugging.\n");
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}
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/* Convert hex digit A to a number. */
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static int
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fromhex (a)
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||
int a;
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||
{
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if (a >= '0' && a <= '9')
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return a - '0';
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else if (a >= 'a' && a <= 'f')
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return a - 'a' + 10;
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else
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error ("Reply contains invalid hex digit");
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return -1;
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}
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/* Convert number NIB to a hex digit. */
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static int
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tohex (nib)
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int nib;
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{
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if (nib < 10)
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return '0'+nib;
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else
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return 'a'+nib-10;
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}
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/* Tell the remote machine to resume. */
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static void
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remote_resume (step, siggnal)
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int step, siggnal;
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{
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char buf[PBUFSIZ];
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if (siggnal)
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{
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char *name;
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target_terminal_ours_for_output ();
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printf_filtered ("Can't send signals to a remote system. ");
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name = strsigno (siggnal);
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if (name)
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printf_filtered (name);
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else
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printf_filtered ("Signal %d", siggnal);
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printf_filtered (" not sent.\n");
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target_terminal_inferior ();
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}
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#if 0
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dcache_flush ();
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#endif
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strcpy (buf, step ? "s": "c");
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putpkt (buf);
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}
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/* Send ^C to target to halt it. Target will respond, and send us a
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packet. */
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static void
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remote_interrupt (signo)
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int signo;
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{
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/* If this doesn't work, try more severe steps. */
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signal (signo, remote_interrupt_twice);
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||
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if (kiodebug)
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printf ("remote_interrupt called\n");
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SERIAL_WRITE (remote_desc, "\003", 1); /* Send a ^C */
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||
}
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||
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static void (*ofunc)();
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/* The user typed ^C twice. */
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static void
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remote_interrupt_twice (signo)
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int signo;
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{
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signal (signo, ofunc);
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target_terminal_ours ();
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||
if (query ("Interrupted while waiting for the program.\n\
|
||
Give up (and stop debugging it)? "))
|
||
{
|
||
target_mourn_inferior ();
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||
return_to_top_level (RETURN_QUIT);
|
||
}
|
||
else
|
||
{
|
||
signal (signo, remote_interrupt);
|
||
target_terminal_inferior ();
|
||
}
|
||
}
|
||
|
||
/* Wait until the remote machine stops, then return,
|
||
storing status in STATUS just as `wait' would.
|
||
Returns "pid" (though it's not clear what, if anything, that
|
||
means in the case of this target). */
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||
|
||
static int
|
||
remote_wait (status)
|
||
WAITTYPE *status;
|
||
{
|
||
unsigned char buf[PBUFSIZ];
|
||
unsigned char *p;
|
||
int i;
|
||
long regno;
|
||
char regs[MAX_REGISTER_RAW_SIZE];
|
||
|
||
WSETEXIT ((*status), 0);
|
||
|
||
ofunc = (void (*)()) signal (SIGINT, remote_interrupt);
|
||
getpkt ((char *) buf, 1);
|
||
signal (SIGINT, ofunc);
|
||
|
||
if (buf[0] == 'E')
|
||
error ("Remote failure reply: %s", buf);
|
||
if (buf[0] == 'T')
|
||
{
|
||
/* Expedited reply, containing Signal, {regno, reg} repeat */
|
||
/* format is: 'Tssn...:r...;n...:r...;n...:r...;#cc', where
|
||
ss = signal number
|
||
n... = register number
|
||
r... = register contents
|
||
*/
|
||
|
||
p = &buf[3]; /* after Txx */
|
||
|
||
while (*p)
|
||
{
|
||
unsigned char *p1;
|
||
|
||
regno = strtol (p, &p1, 16); /* Read the register number */
|
||
|
||
if (p1 == p)
|
||
error ("Remote sent badly formed register number: %s\nPacket: '%s'\n",
|
||
p1, buf);
|
||
|
||
p = p1;
|
||
|
||
if (*p++ != ':')
|
||
error ("Malformed packet (missing colon): %s\nPacket: '%s'\n",
|
||
p, buf);
|
||
|
||
if (regno >= NUM_REGS)
|
||
error ("Remote sent bad register number %d: %s\nPacket: '%s'\n",
|
||
regno, p, buf);
|
||
|
||
for (i = 0; i < REGISTER_RAW_SIZE (regno); i++)
|
||
{
|
||
if (p[0] == 0 || p[1] == 0)
|
||
error ("Remote reply is too short: %s", buf);
|
||
regs[i] = fromhex (p[0]) * 16 + fromhex (p[1]);
|
||
p += 2;
|
||
}
|
||
|
||
if (*p++ != ';')
|
||
error("Remote register badly formatted: %s", buf);
|
||
|
||
supply_register (regno, regs);
|
||
}
|
||
}
|
||
else if (buf[0] != 'S')
|
||
error ("Invalid remote reply: %s", buf);
|
||
|
||
WSETSTOP ((*status), (((fromhex (buf[1])) << 4) + (fromhex (buf[2]))));
|
||
|
||
return 0;
|
||
}
|
||
|
||
/* Read the remote registers into the block REGS. */
|
||
/* Currently we just read all the registers, so we don't use regno. */
|
||
/* ARGSUSED */
|
||
static void
|
||
remote_fetch_registers (regno)
|
||
int regno;
|
||
{
|
||
char buf[PBUFSIZ];
|
||
int i;
|
||
char *p;
|
||
char regs[REGISTER_BYTES];
|
||
|
||
sprintf (buf, "g");
|
||
remote_send (buf);
|
||
|
||
/* Reply describes registers byte by byte, each byte encoded as two
|
||
hex characters. Suck them all up, then supply them to the
|
||
register cacheing/storage mechanism. */
|
||
|
||
p = buf;
|
||
for (i = 0; i < REGISTER_BYTES; i++)
|
||
{
|
||
if (p[0] == 0 || p[1] == 0)
|
||
error ("Remote reply is too short: %s", buf);
|
||
regs[i] = fromhex (p[0]) * 16 + fromhex (p[1]);
|
||
p += 2;
|
||
}
|
||
for (i = 0; i < NUM_REGS; i++)
|
||
supply_register (i, ®s[REGISTER_BYTE(i)]);
|
||
}
|
||
|
||
/* Prepare to store registers. Since we send them all, we have to
|
||
read out the ones we don't want to change first. */
|
||
|
||
static void
|
||
remote_prepare_to_store ()
|
||
{
|
||
/* Make sure the entire registers array is valid. */
|
||
read_register_bytes (0, (char *)NULL, REGISTER_BYTES);
|
||
}
|
||
|
||
/* Store the remote registers from the contents of the block REGISTERS.
|
||
FIXME, eventually just store one register if that's all that is needed. */
|
||
|
||
/* ARGSUSED */
|
||
static void
|
||
remote_store_registers (regno)
|
||
int regno;
|
||
{
|
||
char buf[PBUFSIZ];
|
||
int i;
|
||
char *p;
|
||
|
||
buf[0] = 'G';
|
||
|
||
/* Command describes registers byte by byte,
|
||
each byte encoded as two hex characters. */
|
||
|
||
p = buf + 1;
|
||
for (i = 0; i < REGISTER_BYTES; i++)
|
||
{
|
||
*p++ = tohex ((registers[i] >> 4) & 0xf);
|
||
*p++ = tohex (registers[i] & 0xf);
|
||
}
|
||
*p = '\0';
|
||
|
||
remote_send (buf);
|
||
}
|
||
|
||
#if 0
|
||
/* Read a word from remote address ADDR and return it.
|
||
This goes through the data cache. */
|
||
|
||
int
|
||
remote_fetch_word (addr)
|
||
CORE_ADDR addr;
|
||
{
|
||
if (icache)
|
||
{
|
||
extern CORE_ADDR text_start, text_end;
|
||
|
||
if (addr >= text_start && addr < text_end)
|
||
{
|
||
int buffer;
|
||
xfer_core_file (addr, &buffer, sizeof (int));
|
||
return buffer;
|
||
}
|
||
}
|
||
return dcache_fetch (addr);
|
||
}
|
||
|
||
/* Write a word WORD into remote address ADDR.
|
||
This goes through the data cache. */
|
||
|
||
void
|
||
remote_store_word (addr, word)
|
||
CORE_ADDR addr;
|
||
int word;
|
||
{
|
||
dcache_poke (addr, word);
|
||
}
|
||
#endif /* 0 */
|
||
|
||
/* Write memory data directly to the remote machine.
|
||
This does not inform the data cache; the data cache uses this.
|
||
MEMADDR is the address in the remote memory space.
|
||
MYADDR is the address of the buffer in our space.
|
||
LEN is the number of bytes. */
|
||
|
||
static void
|
||
remote_write_bytes (memaddr, myaddr, len)
|
||
CORE_ADDR memaddr;
|
||
char *myaddr;
|
||
int len;
|
||
{
|
||
char buf[PBUFSIZ];
|
||
int i;
|
||
char *p;
|
||
|
||
if (len > PBUFSIZ / 2 - 20)
|
||
abort ();
|
||
|
||
sprintf (buf, "M%x,%x:", memaddr, len);
|
||
|
||
/* We send target system values byte by byte, in increasing byte addresses,
|
||
each byte encoded as two hex characters. */
|
||
|
||
p = buf + strlen (buf);
|
||
for (i = 0; i < len; i++)
|
||
{
|
||
*p++ = tohex ((myaddr[i] >> 4) & 0xf);
|
||
*p++ = tohex (myaddr[i] & 0xf);
|
||
}
|
||
*p = '\0';
|
||
|
||
remote_send (buf);
|
||
}
|
||
|
||
/* Read memory data directly from the remote machine.
|
||
This does not use the data cache; the data cache uses this.
|
||
MEMADDR is the address in the remote memory space.
|
||
MYADDR is the address of the buffer in our space.
|
||
LEN is the number of bytes. */
|
||
|
||
static void
|
||
remote_read_bytes (memaddr, myaddr, len)
|
||
CORE_ADDR memaddr;
|
||
char *myaddr;
|
||
int len;
|
||
{
|
||
char buf[PBUFSIZ];
|
||
int i;
|
||
char *p;
|
||
|
||
if (len > PBUFSIZ / 2 - 1)
|
||
abort ();
|
||
|
||
sprintf (buf, "m%x,%x", memaddr, len);
|
||
remote_send (buf);
|
||
|
||
/* Reply describes memory byte by byte,
|
||
each byte encoded as two hex characters. */
|
||
|
||
p = buf;
|
||
for (i = 0; i < len; i++)
|
||
{
|
||
if (p[0] == 0 || p[1] == 0)
|
||
error ("Remote reply is too short: %s", buf);
|
||
myaddr[i] = fromhex (p[0]) * 16 + fromhex (p[1]);
|
||
p += 2;
|
||
}
|
||
}
|
||
|
||
/* Read or write LEN bytes from inferior memory at MEMADDR, transferring
|
||
to or from debugger address MYADDR. Write to inferior if SHOULD_WRITE is
|
||
nonzero. Returns length of data written or read; 0 for error. */
|
||
|
||
/* ARGSUSED */
|
||
static int
|
||
remote_xfer_memory(memaddr, myaddr, len, should_write, target)
|
||
CORE_ADDR memaddr;
|
||
char *myaddr;
|
||
int len;
|
||
int should_write;
|
||
struct target_ops *target; /* ignored */
|
||
{
|
||
int origlen = len;
|
||
int xfersize;
|
||
while (len > 0)
|
||
{
|
||
if (len > MAXBUFBYTES)
|
||
xfersize = MAXBUFBYTES;
|
||
else
|
||
xfersize = len;
|
||
|
||
if (should_write)
|
||
remote_write_bytes(memaddr, myaddr, xfersize);
|
||
else
|
||
remote_read_bytes (memaddr, myaddr, xfersize);
|
||
memaddr += xfersize;
|
||
myaddr += xfersize;
|
||
len -= xfersize;
|
||
}
|
||
return origlen; /* no error possible */
|
||
}
|
||
|
||
static void
|
||
remote_files_info (ignore)
|
||
struct target_ops *ignore;
|
||
{
|
||
puts_filtered ("Debugging a target over a serial line.\n");
|
||
}
|
||
|
||
/* Stuff for dealing with the packets which are part of this protocol.
|
||
See comment at top of file for details. */
|
||
|
||
/* Read a single character from the remote end, masking it down to 7 bits. */
|
||
|
||
static int
|
||
readchar ()
|
||
{
|
||
int ch;
|
||
|
||
ch = SERIAL_READCHAR (remote_desc, timeout);
|
||
|
||
if (ch < 0)
|
||
return ch;
|
||
|
||
return ch & 0x7f;
|
||
}
|
||
|
||
/* Send the command in BUF to the remote machine,
|
||
and read the reply into BUF.
|
||
Report an error if we get an error reply. */
|
||
|
||
static void
|
||
remote_send (buf)
|
||
char *buf;
|
||
{
|
||
|
||
putpkt (buf);
|
||
getpkt (buf, 0);
|
||
|
||
if (buf[0] == 'E')
|
||
error ("Remote failure reply: %s", buf);
|
||
}
|
||
|
||
/* Send a packet to the remote machine, with error checking.
|
||
The data of the packet is in BUF. */
|
||
|
||
static void
|
||
putpkt (buf)
|
||
char *buf;
|
||
{
|
||
int i;
|
||
unsigned char csum = 0;
|
||
char buf2[PBUFSIZ];
|
||
int cnt = strlen (buf);
|
||
int ch;
|
||
char *p;
|
||
|
||
/* Copy the packet into buffer BUF2, encapsulating it
|
||
and giving it a checksum. */
|
||
|
||
if (cnt > sizeof(buf2) - 5) /* Prosanity check */
|
||
abort();
|
||
|
||
p = buf2;
|
||
*p++ = '$';
|
||
|
||
for (i = 0; i < cnt; i++)
|
||
{
|
||
csum += buf[i];
|
||
*p++ = buf[i];
|
||
}
|
||
*p++ = '#';
|
||
*p++ = tohex ((csum >> 4) & 0xf);
|
||
*p++ = tohex (csum & 0xf);
|
||
|
||
/* Send it over and over until we get a positive ack. */
|
||
|
||
while (1)
|
||
{
|
||
if (kiodebug)
|
||
{
|
||
*p = '\0';
|
||
printf ("Sending packet: %s...", buf2); fflush(stdout);
|
||
}
|
||
if (SERIAL_WRITE (remote_desc, buf2, p - buf2))
|
||
perror_with_name ("putpkt: write failed");
|
||
|
||
/* read until either a timeout occurs (-2) or '+' is read */
|
||
while (1)
|
||
{
|
||
ch = readchar ();
|
||
|
||
switch (ch)
|
||
{
|
||
case '+':
|
||
if (kiodebug)
|
||
printf("Ack\n");
|
||
return;
|
||
case SERIAL_TIMEOUT:
|
||
break; /* Retransmit buffer */
|
||
case SERIAL_ERROR:
|
||
perror_with_name ("putpkt: couldn't read ACK");
|
||
case SERIAL_EOF:
|
||
error ("putpkt: EOF while trying to read ACK");
|
||
default:
|
||
if (kiodebug)
|
||
printf ("%02X %c ", ch&0xFF, ch);
|
||
continue;
|
||
}
|
||
break; /* Here to retransmit */
|
||
}
|
||
}
|
||
}
|
||
|
||
/* Read a packet from the remote machine, with error checking,
|
||
and store it in BUF. BUF is expected to be of size PBUFSIZ.
|
||
If FOREVER, wait forever rather than timing out; this is used
|
||
while the target is executing user code. */
|
||
|
||
static void
|
||
getpkt (buf, forever)
|
||
char *buf;
|
||
int forever;
|
||
{
|
||
char *bp;
|
||
unsigned char csum;
|
||
int c = 0;
|
||
unsigned char c1, c2;
|
||
int retries = 0;
|
||
#define MAX_RETRIES 10
|
||
|
||
while (1)
|
||
{
|
||
/* This can loop forever if the remote side sends us characters
|
||
continuously, but if it pauses, we'll get a zero from readchar
|
||
because of timeout. Then we'll count that as a retry. */
|
||
|
||
c = readchar();
|
||
if (c > 0 && c != '$')
|
||
continue;
|
||
|
||
if (c == SERIAL_TIMEOUT)
|
||
{
|
||
if (forever)
|
||
continue;
|
||
if (++retries >= MAX_RETRIES)
|
||
if (kiodebug) puts_filtered ("Timed out.\n");
|
||
goto out;
|
||
}
|
||
|
||
if (c == SERIAL_EOF)
|
||
error ("Remote connection closed");
|
||
if (c == SERIAL_ERROR)
|
||
perror_with_name ("Remote communication error");
|
||
|
||
/* Force csum to be zero here because of possible error retry. */
|
||
csum = 0;
|
||
bp = buf;
|
||
|
||
while (1)
|
||
{
|
||
c = readchar ();
|
||
if (c == SERIAL_TIMEOUT)
|
||
{
|
||
if (kiodebug)
|
||
puts_filtered ("Timeout in mid-packet, retrying\n");
|
||
goto whole; /* Start a new packet, count retries */
|
||
}
|
||
if (c == '$')
|
||
{
|
||
if (kiodebug)
|
||
puts_filtered ("Saw new packet start in middle of old one\n");
|
||
goto whole; /* Start a new packet, count retries */
|
||
}
|
||
if (c == '#')
|
||
break;
|
||
if (bp >= buf+PBUFSIZ-1)
|
||
{
|
||
*bp = '\0';
|
||
puts_filtered ("Remote packet too long: ");
|
||
puts_filtered (buf);
|
||
puts_filtered ("\n");
|
||
goto whole;
|
||
}
|
||
*bp++ = c;
|
||
csum += c;
|
||
}
|
||
*bp = 0;
|
||
|
||
c1 = fromhex (readchar ());
|
||
c2 = fromhex (readchar ());
|
||
if ((csum & 0xff) == (c1 << 4) + c2)
|
||
break;
|
||
printf_filtered ("Bad checksum, sentsum=0x%x, csum=0x%x, buf=",
|
||
(c1 << 4) + c2, csum & 0xff);
|
||
puts_filtered (buf);
|
||
puts_filtered ("\n");
|
||
|
||
/* Try the whole thing again. */
|
||
whole:
|
||
if (++retries < MAX_RETRIES)
|
||
{
|
||
SERIAL_WRITE (remote_desc, "-", 1);
|
||
}
|
||
else
|
||
{
|
||
printf ("Ignoring packet error, continuing...\n");
|
||
break;
|
||
}
|
||
}
|
||
|
||
out:
|
||
|
||
SERIAL_WRITE (remote_desc, "+", 1);
|
||
|
||
if (kiodebug)
|
||
fprintf (stderr,"Packet received: %s\n", buf);
|
||
}
|
||
|
||
/* The data cache leads to incorrect results because it doesn't know about
|
||
volatile variables, thus making it impossible to debug functions which
|
||
use hardware registers. Therefore it is #if 0'd out. Effect on
|
||
performance is some, for backtraces of functions with a few
|
||
arguments each. For functions with many arguments, the stack
|
||
frames don't fit in the cache blocks, which makes the cache less
|
||
helpful. Disabling the cache is a big performance win for fetching
|
||
large structures, because the cache code fetched data in 16-byte
|
||
chunks. */
|
||
#if 0
|
||
/* The data cache records all the data read from the remote machine
|
||
since the last time it stopped.
|
||
|
||
Each cache block holds 16 bytes of data
|
||
starting at a multiple-of-16 address. */
|
||
|
||
#define DCACHE_SIZE 64 /* Number of cache blocks */
|
||
|
||
struct dcache_block {
|
||
struct dcache_block *next, *last;
|
||
unsigned int addr; /* Address for which data is recorded. */
|
||
int data[4];
|
||
};
|
||
|
||
struct dcache_block dcache_free, dcache_valid;
|
||
|
||
/* Free all the data cache blocks, thus discarding all cached data. */
|
||
|
||
static void
|
||
dcache_flush ()
|
||
{
|
||
register struct dcache_block *db;
|
||
|
||
while ((db = dcache_valid.next) != &dcache_valid)
|
||
{
|
||
remque (db);
|
||
insque (db, &dcache_free);
|
||
}
|
||
}
|
||
|
||
/*
|
||
* If addr is present in the dcache, return the address of the block
|
||
* containing it.
|
||
*/
|
||
|
||
struct dcache_block *
|
||
dcache_hit (addr)
|
||
{
|
||
register struct dcache_block *db;
|
||
|
||
if (addr & 3)
|
||
abort ();
|
||
|
||
/* Search all cache blocks for one that is at this address. */
|
||
db = dcache_valid.next;
|
||
while (db != &dcache_valid)
|
||
{
|
||
if ((addr & 0xfffffff0) == db->addr)
|
||
return db;
|
||
db = db->next;
|
||
}
|
||
return NULL;
|
||
}
|
||
|
||
/* Return the int data at address ADDR in dcache block DC. */
|
||
|
||
int
|
||
dcache_value (db, addr)
|
||
struct dcache_block *db;
|
||
unsigned int addr;
|
||
{
|
||
if (addr & 3)
|
||
abort ();
|
||
return (db->data[(addr>>2)&3]);
|
||
}
|
||
|
||
/* Get a free cache block, put it on the valid list,
|
||
and return its address. The caller should store into the block
|
||
the address and data that it describes. */
|
||
|
||
struct dcache_block *
|
||
dcache_alloc ()
|
||
{
|
||
register struct dcache_block *db;
|
||
|
||
if ((db = dcache_free.next) == &dcache_free)
|
||
/* If we can't get one from the free list, take last valid */
|
||
db = dcache_valid.last;
|
||
|
||
remque (db);
|
||
insque (db, &dcache_valid);
|
||
return (db);
|
||
}
|
||
|
||
/* Return the contents of the word at address ADDR in the remote machine,
|
||
using the data cache. */
|
||
|
||
int
|
||
dcache_fetch (addr)
|
||
CORE_ADDR addr;
|
||
{
|
||
register struct dcache_block *db;
|
||
|
||
db = dcache_hit (addr);
|
||
if (db == 0)
|
||
{
|
||
db = dcache_alloc ();
|
||
remote_read_bytes (addr & ~0xf, db->data, 16);
|
||
db->addr = addr & ~0xf;
|
||
}
|
||
return (dcache_value (db, addr));
|
||
}
|
||
|
||
/* Write the word at ADDR both in the data cache and in the remote machine. */
|
||
|
||
dcache_poke (addr, data)
|
||
CORE_ADDR addr;
|
||
int data;
|
||
{
|
||
register struct dcache_block *db;
|
||
|
||
/* First make sure the word is IN the cache. DB is its cache block. */
|
||
db = dcache_hit (addr);
|
||
if (db == 0)
|
||
{
|
||
db = dcache_alloc ();
|
||
remote_read_bytes (addr & ~0xf, db->data, 16);
|
||
db->addr = addr & ~0xf;
|
||
}
|
||
|
||
/* Modify the word in the cache. */
|
||
db->data[(addr>>2)&3] = data;
|
||
|
||
/* Send the changed word. */
|
||
remote_write_bytes (addr, &data, 4);
|
||
}
|
||
|
||
/* Initialize the data cache. */
|
||
|
||
dcache_init ()
|
||
{
|
||
register i;
|
||
register struct dcache_block *db;
|
||
|
||
db = (struct dcache_block *) xmalloc (sizeof (struct dcache_block) *
|
||
DCACHE_SIZE);
|
||
dcache_free.next = dcache_free.last = &dcache_free;
|
||
dcache_valid.next = dcache_valid.last = &dcache_valid;
|
||
for (i=0;i<DCACHE_SIZE;i++,db++)
|
||
insque (db, &dcache_free);
|
||
}
|
||
#endif /* 0 */
|
||
|
||
static void
|
||
remote_kill ()
|
||
{
|
||
putpkt ("k");
|
||
/* Don't wait for it to die. I'm not really sure it matters whether
|
||
we do or not. For the existing stubs, kill is a noop. */
|
||
target_mourn_inferior ();
|
||
}
|
||
|
||
static void
|
||
remote_mourn ()
|
||
{
|
||
unpush_target (&remote_ops);
|
||
generic_mourn_inferior ();
|
||
}
|
||
|
||
#ifdef REMOTE_BREAKPOINT
|
||
|
||
/* On some machines, e.g. 68k, we may use a different breakpoint instruction
|
||
than other targets. */
|
||
static unsigned char break_insn[] = REMOTE_BREAKPOINT;
|
||
|
||
/* Check that it fits in BREAKPOINT_MAX bytes. */
|
||
static unsigned char check_break_insn_size[BREAKPOINT_MAX] = REMOTE_BREAKPOINT;
|
||
|
||
#else /* No REMOTE_BREAKPOINT. */
|
||
|
||
/* Same old breakpoint instruction. This code does nothing different
|
||
than mem-break.c. */
|
||
static unsigned char break_insn[] = BREAKPOINT;
|
||
|
||
#endif /* No REMOTE_BREAKPOINT. */
|
||
|
||
/* Insert a breakpoint on targets that don't have any better breakpoint
|
||
support. We read the contents of the target location and stash it,
|
||
then overwrite it with a breakpoint instruction. ADDR is the target
|
||
location in the target machine. CONTENTS_CACHE is a pointer to
|
||
memory allocated for saving the target contents. It is guaranteed
|
||
by the caller to be long enough to save sizeof BREAKPOINT bytes (this
|
||
is accomplished via BREAKPOINT_MAX). */
|
||
|
||
int
|
||
remote_insert_breakpoint (addr, contents_cache)
|
||
CORE_ADDR addr;
|
||
char *contents_cache;
|
||
{
|
||
int val;
|
||
|
||
val = target_read_memory (addr, contents_cache, sizeof break_insn);
|
||
|
||
if (val == 0)
|
||
val = target_write_memory (addr, (char *)break_insn, sizeof break_insn);
|
||
|
||
return val;
|
||
}
|
||
|
||
int
|
||
remote_remove_breakpoint (addr, contents_cache)
|
||
CORE_ADDR addr;
|
||
char *contents_cache;
|
||
{
|
||
return target_write_memory (addr, contents_cache, sizeof break_insn);
|
||
}
|
||
|
||
/* Define the target subroutine names */
|
||
|
||
struct target_ops remote_ops = {
|
||
"remote", /* to_shortname */
|
||
"Remote serial target in gdb-specific protocol", /* to_longname */
|
||
"Use a remote computer via a serial line, using a gdb-specific protocol.\n\
|
||
Specify the serial device it is connected to (e.g. /dev/ttya).", /* to_doc */
|
||
remote_open, /* to_open */
|
||
remote_close, /* to_close */
|
||
NULL, /* to_attach */
|
||
remote_detach, /* to_detach */
|
||
remote_resume, /* to_resume */
|
||
remote_wait, /* to_wait */
|
||
remote_fetch_registers, /* to_fetch_registers */
|
||
remote_store_registers, /* to_store_registers */
|
||
remote_prepare_to_store, /* to_prepare_to_store */
|
||
remote_xfer_memory, /* to_xfer_memory */
|
||
remote_files_info, /* to_files_info */
|
||
|
||
remote_insert_breakpoint, /* to_insert_breakpoint */
|
||
remote_remove_breakpoint, /* to_remove_breakpoint */
|
||
|
||
NULL, /* to_terminal_init */
|
||
NULL, /* to_terminal_inferior */
|
||
NULL, /* to_terminal_ours_for_output */
|
||
NULL, /* to_terminal_ours */
|
||
NULL, /* to_terminal_info */
|
||
remote_kill, /* to_kill */
|
||
generic_load, /* to_load */
|
||
NULL, /* to_lookup_symbol */
|
||
NULL, /* to_create_inferior */
|
||
remote_mourn, /* to_mourn_inferior */
|
||
0, /* to_can_run */
|
||
0, /* to_notice_signals */
|
||
process_stratum, /* to_stratum */
|
||
NULL, /* to_next */
|
||
1, /* to_has_all_memory */
|
||
1, /* to_has_memory */
|
||
1, /* to_has_stack */
|
||
1, /* to_has_registers */
|
||
1, /* to_has_execution */
|
||
NULL, /* sections */
|
||
NULL, /* sections_end */
|
||
OPS_MAGIC /* to_magic */
|
||
};
|
||
|
||
void
|
||
_initialize_remote ()
|
||
{
|
||
add_target (&remote_ops);
|
||
|
||
add_show_from_set (
|
||
add_set_cmd ("remotedebug", no_class, var_boolean, (char *)&kiodebug,
|
||
"Set debugging of remote serial I/O.\n\
|
||
When enabled, each packet sent or received with the remote target\n\
|
||
is displayed.", &setlist),
|
||
&showlist);
|
||
}
|
||
|
||
#endif
|