4f8a48e5a2
inside a loop. User can ^C to get out.
1167 lines
28 KiB
C
1167 lines
28 KiB
C
/* Remote target communications for serial-line targets in custom GDB protocol
|
||
Copyright 1988, 1991, 1992, 1993 Free Software Foundation, Inc.
|
||
|
||
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., 675 Mass Ave, Cambridge, MA 02139, USA. */
|
||
|
||
/* Remote communication protocol.
|
||
|
||
A debug packet whose contents are <data>
|
||
is encapsulated for transmission in the form:
|
||
|
||
$ <data> # CSUM1 CSUM2
|
||
|
||
<data> must be ASCII alphanumeric and cannot include characters
|
||
'$' or '#'
|
||
|
||
CSUM1 and CSUM2 are ascii hex representation of an 8-bit
|
||
checksum of <data>, the most significant nibble is sent first.
|
||
the hex digits 0-9,a-f are used.
|
||
|
||
Receiver responds with:
|
||
|
||
+ - if CSUM is correct and ready for next packet
|
||
- - if CSUM is incorrect
|
||
|
||
<data> is as follows:
|
||
All values are encoded in ascii hex digits.
|
||
|
||
Request Packet
|
||
|
||
read registers g
|
||
reply XX....X Each byte of register data
|
||
is described by two hex digits.
|
||
Registers are in the internal order
|
||
for GDB, and the bytes in a register
|
||
are in the same order the machine uses.
|
||
or ENN for an error.
|
||
|
||
write regs GXX..XX Each byte of register data
|
||
is described by two hex digits.
|
||
reply OK for success
|
||
ENN for an error
|
||
|
||
read mem mAA..AA,LLLL AA..AA is address, LLLL is length.
|
||
reply XX..XX XX..XX is mem contents
|
||
Can be fewer bytes than requested
|
||
if able to read only part of the data.
|
||
or ENN NN is errno
|
||
|
||
write mem MAA..AA,LLLL:XX..XX
|
||
AA..AA is address,
|
||
LLLL is number of bytes,
|
||
XX..XX is data
|
||
reply OK for success
|
||
ENN for an error (this includes the case
|
||
where only part of the data was
|
||
written).
|
||
|
||
cont cAA..AA AA..AA is address to resume
|
||
If AA..AA is omitted,
|
||
resume at same address.
|
||
|
||
step sAA..AA AA..AA is address to resume
|
||
If AA..AA is omitted,
|
||
resume at same address.
|
||
|
||
last signal ? Reply the current reason for stopping.
|
||
This is the same reply as is generated
|
||
for step or cont : SAA where AA is the
|
||
signal number.
|
||
|
||
There is no immediate reply to step or cont.
|
||
The reply comes when the machine stops.
|
||
It is SAA AA is the "signal number"
|
||
|
||
or... TAAn...:r...;n:r...;n...:r...;
|
||
AA = signal number
|
||
n... = register number
|
||
r... = register contents
|
||
or... WAA The process extited, and AA is
|
||
the exit status. This is only
|
||
applicable for certains sorts of
|
||
targets.
|
||
or... NAATT;DD;BB Relocate the object file.
|
||
AA = signal number
|
||
TT = text address
|
||
DD = data address
|
||
BB = bss address
|
||
This is used by the NLM stub,
|
||
which is why it only has three
|
||
addresses rather than one per
|
||
section: the NLM stub always
|
||
sees only three sections, even
|
||
though gdb may see more.
|
||
|
||
kill request k
|
||
|
||
toggle debug d toggle debug flag (see 386 & 68k stubs)
|
||
reset r reset -- see sparc stub.
|
||
reserved <other> On other requests, the stub should
|
||
ignore the request and send an empty
|
||
response ($#<checksum>). This way
|
||
we can extend the protocol and GDB
|
||
can tell whether the stub it is
|
||
talking to uses the old or the new.
|
||
*/
|
||
|
||
#include "defs.h"
|
||
#include <string.h>
|
||
#include <fcntl.h>
|
||
#include "frame.h"
|
||
#include "inferior.h"
|
||
#include "bfd.h"
|
||
#include "symfile.h"
|
||
#include "target.h"
|
||
#include "wait.h"
|
||
#include "terminal.h"
|
||
#include "gdbcmd.h"
|
||
#include "objfiles.h"
|
||
#include "gdb-stabs.h"
|
||
|
||
#include "dcache.h"
|
||
|
||
#if !defined(DONT_USE_REMOTE)
|
||
#ifdef USG
|
||
#include <sys/types.h>
|
||
#endif
|
||
|
||
#include <signal.h>
|
||
#include "serial.h"
|
||
|
||
/* Prototypes for local functions */
|
||
|
||
static int
|
||
remote_write_bytes PARAMS ((CORE_ADDR memaddr, unsigned char *myaddr, int len));
|
||
|
||
static int
|
||
remote_read_bytes PARAMS ((CORE_ADDR memaddr, unsigned char *myaddr, int len));
|
||
|
||
static void
|
||
remote_files_info PARAMS ((struct target_ops *ignore));
|
||
|
||
static int
|
||
remote_xfer_memory PARAMS ((CORE_ADDR memaddr, char *myaddr, int len,
|
||
int should_write, struct target_ops *target));
|
||
|
||
static void
|
||
remote_prepare_to_store PARAMS ((void));
|
||
|
||
static void
|
||
remote_fetch_registers PARAMS ((int regno));
|
||
|
||
static void
|
||
remote_resume PARAMS ((int pid, int step, int siggnal));
|
||
|
||
static int
|
||
remote_start_remote PARAMS ((char *dummy));
|
||
|
||
static void
|
||
remote_open PARAMS ((char *name, int from_tty));
|
||
|
||
static void
|
||
remote_close PARAMS ((int quitting));
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||
|
||
static void
|
||
remote_store_registers PARAMS ((int regno));
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||
|
||
static void
|
||
getpkt PARAMS ((char *buf, int forever));
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||
|
||
static void
|
||
putpkt PARAMS ((char *buf));
|
||
|
||
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
|
||
remote_wait PARAMS ((WAITTYPE *status));
|
||
|
||
static int
|
||
tohex PARAMS ((int nib));
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||
|
||
static int
|
||
fromhex PARAMS ((int a));
|
||
|
||
static void
|
||
remote_detach PARAMS ((char *args, int from_tty));
|
||
|
||
static void
|
||
remote_interrupt PARAMS ((int signo));
|
||
|
||
static void
|
||
remote_interrupt_twice PARAMS ((int signo));
|
||
|
||
extern struct target_ops remote_ops; /* Forward decl */
|
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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. */
|
||
static int timeout = 2;
|
||
|
||
#if 0
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int icache;
|
||
#endif
|
||
|
||
/* 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
|
||
starts. */
|
||
serial_t remote_desc = NULL;
|
||
|
||
#define PBUFSIZ 1024
|
||
|
||
/* Maximum number of bytes to read/write at once. The value here
|
||
is chosen to fill up a packet (the headers account for the 32). */
|
||
#define MAXBUFBYTES ((PBUFSIZ-32)/2)
|
||
|
||
/* Round up PBUFSIZ to hold all the registers, at least. */
|
||
#if REGISTER_BYTES > MAXBUFBYTES
|
||
#undef PBUFSIZ
|
||
#define PBUFSIZ (REGISTER_BYTES * 2 + 32)
|
||
#endif
|
||
|
||
/* Clean up connection to a remote debugger. */
|
||
|
||
/* ARGSUSED */
|
||
static void
|
||
remote_close (quitting)
|
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int quitting;
|
||
{
|
||
if (remote_desc)
|
||
SERIAL_CLOSE (remote_desc);
|
||
remote_desc = NULL;
|
||
}
|
||
|
||
/* Stub for catch_errors. */
|
||
|
||
static int
|
||
remote_start_remote (dummy)
|
||
char *dummy;
|
||
{
|
||
immediate_quit = 1; /* Allow user to interrupt it */
|
||
|
||
/* Ack any packet which the remote side has already sent. */
|
||
/* I'm not sure this \r is needed; we don't use it any other time we
|
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send an ack. */
|
||
SERIAL_WRITE (remote_desc, "+\r", 2);
|
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putpkt ("?"); /* initiate a query from remote machine */
|
||
immediate_quit = 0;
|
||
|
||
start_remote (); /* Initialize gdb process mechanisms */
|
||
return 1;
|
||
}
|
||
|
||
/* Open a connection to a remote debugger.
|
||
NAME is the filename used for communication. */
|
||
|
||
static DCACHE *remote_dcache;
|
||
|
||
static void
|
||
remote_open (name, from_tty)
|
||
char *name;
|
||
int from_tty;
|
||
{
|
||
if (name == 0)
|
||
error (
|
||
"To open a remote debug connection, you need to specify what serial\n\
|
||
device is attached to the remote system (e.g. /dev/ttya).");
|
||
|
||
target_preopen (from_tty);
|
||
|
||
unpush_target (&remote_ops);
|
||
|
||
remote_dcache = dcache_init (remote_read_bytes, remote_write_bytes);
|
||
|
||
remote_desc = SERIAL_OPEN (name);
|
||
if (!remote_desc)
|
||
perror_with_name (name);
|
||
|
||
if (baud_rate)
|
||
{
|
||
int rate;
|
||
|
||
if (sscanf (baud_rate, "%d", &rate) == 1)
|
||
if (SERIAL_SETBAUDRATE (remote_desc, rate))
|
||
{
|
||
SERIAL_CLOSE (remote_desc);
|
||
perror_with_name (name);
|
||
}
|
||
}
|
||
|
||
SERIAL_RAW (remote_desc);
|
||
|
||
if (from_tty)
|
||
{
|
||
puts_filtered ("Remote debugging using ");
|
||
puts_filtered (name);
|
||
puts_filtered ("\n");
|
||
}
|
||
push_target (&remote_ops); /* Switch to using remote target now */
|
||
|
||
/* Start the remote connection; if error (0), discard this target.
|
||
In particular, if the user quits, be sure to discard it
|
||
(we'd be in an inconsistent state otherwise). */
|
||
if (!catch_errors (remote_start_remote, (char *)0,
|
||
"Couldn't establish connection to remote target\n", RETURN_MASK_ALL))
|
||
pop_target();
|
||
}
|
||
|
||
/* remote_detach()
|
||
takes a program previously attached to and detaches it.
|
||
We better not have left any breakpoints
|
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in the program or it'll die when it hits one.
|
||
Close the open connection to the remote debugger.
|
||
Use this when you want to detach and do something else
|
||
with your gdb. */
|
||
|
||
static void
|
||
remote_detach (args, from_tty)
|
||
char *args;
|
||
int from_tty;
|
||
{
|
||
if (args)
|
||
error ("Argument given to \"detach\" when remotely debugging.");
|
||
|
||
pop_target ();
|
||
if (from_tty)
|
||
puts_filtered ("Ending remote debugging.\n");
|
||
}
|
||
|
||
/* Convert hex digit A to a number. */
|
||
|
||
static int
|
||
fromhex (a)
|
||
int a;
|
||
{
|
||
if (a >= '0' && a <= '9')
|
||
return a - '0';
|
||
else if (a >= 'a' && a <= 'f')
|
||
return a - 'a' + 10;
|
||
else
|
||
error ("Reply contains invalid hex digit");
|
||
return -1;
|
||
}
|
||
|
||
/* Convert number NIB to a hex digit. */
|
||
|
||
static int
|
||
tohex (nib)
|
||
int nib;
|
||
{
|
||
if (nib < 10)
|
||
return '0'+nib;
|
||
else
|
||
return 'a'+nib-10;
|
||
}
|
||
|
||
/* Tell the remote machine to resume. */
|
||
|
||
static void
|
||
remote_resume (pid, step, siggnal)
|
||
int pid, step, siggnal;
|
||
{
|
||
char buf[PBUFSIZ];
|
||
|
||
if (siggnal)
|
||
{
|
||
char *name;
|
||
target_terminal_ours_for_output ();
|
||
printf_filtered ("Can't send signals to a remote system. ");
|
||
name = strsigno (siggnal);
|
||
if (name)
|
||
printf_filtered (name);
|
||
else
|
||
printf_filtered ("Signal %d", siggnal);
|
||
printf_filtered (" not sent.\n");
|
||
target_terminal_inferior ();
|
||
}
|
||
|
||
dcache_flush (remote_dcache);
|
||
|
||
strcpy (buf, step ? "s": "c");
|
||
|
||
putpkt (buf);
|
||
}
|
||
|
||
/* Send ^C to target to halt it. Target will respond, and send us a
|
||
packet. */
|
||
|
||
static void
|
||
remote_interrupt (signo)
|
||
int signo;
|
||
{
|
||
/* If this doesn't work, try more severe steps. */
|
||
signal (signo, remote_interrupt_twice);
|
||
|
||
if (remote_debug)
|
||
printf ("remote_interrupt called\n");
|
||
|
||
SERIAL_WRITE (remote_desc, "\003", 1); /* Send a ^C */
|
||
}
|
||
|
||
static void (*ofunc)();
|
||
|
||
/* The user typed ^C twice. */
|
||
static void
|
||
remote_interrupt_twice (signo)
|
||
int signo;
|
||
{
|
||
signal (signo, ofunc);
|
||
|
||
target_terminal_ours ();
|
||
if (query ("Interrupted while waiting for the program.\n\
|
||
Give up (and stop debugging it)? "))
|
||
{
|
||
target_mourn_inferior ();
|
||
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). */
|
||
|
||
static int
|
||
remote_wait (status)
|
||
WAITTYPE *status;
|
||
{
|
||
unsigned char buf[PBUFSIZ];
|
||
|
||
WSETEXIT ((*status), 0);
|
||
|
||
while (1)
|
||
{
|
||
unsigned char *p;
|
||
|
||
ofunc = (void (*)()) signal (SIGINT, remote_interrupt);
|
||
getpkt ((char *) buf, 1);
|
||
signal (SIGINT, ofunc);
|
||
|
||
if (buf[0] == 'E')
|
||
warning ("Remote failure reply: %s", buf);
|
||
else if (buf[0] == 'T')
|
||
{
|
||
int i;
|
||
long regno;
|
||
char regs[MAX_REGISTER_RAW_SIZE];
|
||
|
||
/* 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)
|
||
warning ("Remote sent badly formed register number: %s\nPacket: '%s'\n",
|
||
p1, buf);
|
||
|
||
p = p1;
|
||
|
||
if (*p++ != ':')
|
||
warning ("Malformed packet (missing colon): %s\nPacket: '%s'\n",
|
||
p, buf);
|
||
|
||
if (regno >= NUM_REGS)
|
||
warning ("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)
|
||
warning ("Remote reply is too short: %s", buf);
|
||
regs[i] = fromhex (p[0]) * 16 + fromhex (p[1]);
|
||
p += 2;
|
||
}
|
||
|
||
if (*p++ != ';')
|
||
warning ("Remote register badly formatted: %s", buf);
|
||
|
||
supply_register (regno, regs);
|
||
}
|
||
break;
|
||
}
|
||
else if (buf[0] == 'N')
|
||
{
|
||
unsigned char *p1;
|
||
bfd_vma text_addr, data_addr, bss_addr;
|
||
|
||
/* Relocate object file. Format is NAATT;DD;BB where AA is
|
||
the signal number, TT is the new text address, DD is the
|
||
new data address, and BB is the new bss address. This is
|
||
used by the NLM stub; gdb may see more sections. */
|
||
p = &buf[3];
|
||
text_addr = strtol (p, &p1, 16);
|
||
if (p1 == p || *p1 != ';')
|
||
warning ("Malformed relocation packet: Packet '%s'", buf);
|
||
p = p1 + 1;
|
||
data_addr = strtol (p, &p1, 16);
|
||
if (p1 == p || *p1 != ';')
|
||
warning ("Malformed relocation packet: Packet '%s'", buf);
|
||
p = p1 + 1;
|
||
bss_addr = strtol (p, &p1, 16);
|
||
if (p1 == p)
|
||
warning ("Malformed relocation packet: Packet '%s'", buf);
|
||
|
||
if (symfile_objfile != NULL)
|
||
{
|
||
struct section_offsets *offs;
|
||
|
||
/* FIXME: Why don't the various symfile_offsets routines
|
||
in the sym_fns vectors set this? */
|
||
if (symfile_objfile->num_sections == 0)
|
||
symfile_objfile->num_sections = SECT_OFF_MAX;
|
||
|
||
offs = ((struct section_offsets *)
|
||
alloca (sizeof (struct section_offsets)
|
||
+ (symfile_objfile->num_sections
|
||
* sizeof (offs->offsets))));
|
||
memcpy (offs, symfile_objfile->section_offsets,
|
||
(sizeof (struct section_offsets)
|
||
+ (symfile_objfile->num_sections
|
||
* sizeof (offs->offsets))));
|
||
ANOFFSET (offs, SECT_OFF_TEXT) = text_addr;
|
||
ANOFFSET (offs, SECT_OFF_DATA) = data_addr;
|
||
ANOFFSET (offs, SECT_OFF_BSS) = bss_addr;
|
||
|
||
objfile_relocate (symfile_objfile, offs);
|
||
}
|
||
break;
|
||
}
|
||
else if (buf[0] == 'W')
|
||
{
|
||
/* The remote process exited. */
|
||
WSETEXIT (*status, (fromhex (buf[1]) << 4) + fromhex (buf[2]));
|
||
return 0;
|
||
}
|
||
else if (buf[0] == 'S')
|
||
break;
|
||
else
|
||
warning ("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
|
||
|
||
/* Use of the data cache is disabled because it loses for looking at
|
||
and changing hardware I/O ports and the like. Accepting `volatile'
|
||
would perhaps be one way to fix it, but a better way which would
|
||
win for more cases would be to use the executable file for the text
|
||
segment, like the `icache' code below but done cleanly (in some
|
||
target-independent place, perhaps in target_xfer_memory, perhaps
|
||
based on assigning each target a speed or perhaps by some simpler
|
||
mechanism). */
|
||
|
||
/* Read a word from remote address ADDR and return it.
|
||
This goes through the data cache. */
|
||
|
||
static int
|
||
remote_fetch_word (addr)
|
||
CORE_ADDR addr;
|
||
{
|
||
#if 0
|
||
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;
|
||
}
|
||
}
|
||
#endif
|
||
return dcache_fetch (remote_dcache, addr);
|
||
}
|
||
|
||
/* Write a word WORD into remote address ADDR.
|
||
This goes through the data cache. */
|
||
|
||
static void
|
||
remote_store_word (addr, word)
|
||
CORE_ADDR addr;
|
||
int word;
|
||
{
|
||
dcache_poke (remote_dcache, 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.
|
||
|
||
Returns number of bytes transferred, or 0 for error. */
|
||
|
||
static int
|
||
remote_write_bytes (memaddr, myaddr, len)
|
||
CORE_ADDR memaddr;
|
||
unsigned 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';
|
||
|
||
putpkt (buf);
|
||
getpkt (buf, 0);
|
||
|
||
if (buf[0] == 'E')
|
||
{
|
||
/* There is no correspondance between what the remote protocol uses
|
||
for errors and errno codes. We would like a cleaner way of
|
||
representing errors (big enough to include errno codes, bfd_error
|
||
codes, and others). But for now just return EIO. */
|
||
errno = EIO;
|
||
return 0;
|
||
}
|
||
return len;
|
||
}
|
||
|
||
/* 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.
|
||
|
||
Returns number of bytes transferred, or 0 for error. */
|
||
|
||
static int
|
||
remote_read_bytes (memaddr, myaddr, len)
|
||
CORE_ADDR memaddr;
|
||
unsigned char *myaddr;
|
||
int len;
|
||
{
|
||
char buf[PBUFSIZ];
|
||
int i;
|
||
char *p;
|
||
|
||
if (len > PBUFSIZ / 2 - 1)
|
||
abort ();
|
||
|
||
sprintf (buf, "m%x,%x", memaddr, len);
|
||
putpkt (buf);
|
||
getpkt (buf, 0);
|
||
|
||
if (buf[0] == 'E')
|
||
{
|
||
/* There is no correspondance between what the remote protocol uses
|
||
for errors and errno codes. We would like a cleaner way of
|
||
representing errors (big enough to include errno codes, bfd_error
|
||
codes, and others). But for now just return EIO. */
|
||
errno = EIO;
|
||
return 0;
|
||
}
|
||
|
||
/* 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)
|
||
/* Reply is short. This means that we were able to read only part
|
||
of what we wanted to. */
|
||
break;
|
||
myaddr[i] = fromhex (p[0]) * 16 + fromhex (p[1]);
|
||
p += 2;
|
||
}
|
||
return i;
|
||
}
|
||
|
||
/* 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 xfersize;
|
||
int bytes_xferred;
|
||
int total_xferred = 0;
|
||
|
||
while (len > 0)
|
||
{
|
||
if (len > MAXBUFBYTES)
|
||
xfersize = MAXBUFBYTES;
|
||
else
|
||
xfersize = len;
|
||
|
||
if (should_write)
|
||
bytes_xferred = remote_write_bytes (memaddr, myaddr, xfersize);
|
||
else
|
||
bytes_xferred = remote_read_bytes (memaddr, myaddr, xfersize);
|
||
|
||
/* If we get an error, we are done xferring. */
|
||
if (bytes_xferred == 0)
|
||
break;
|
||
|
||
memaddr += bytes_xferred;
|
||
myaddr += bytes_xferred;
|
||
len -= bytes_xferred;
|
||
total_xferred += bytes_xferred;
|
||
}
|
||
return total_xferred;
|
||
}
|
||
|
||
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++ = '$';
|
||
|
||
for (i = 0; i < cnt; i++)
|
||
{
|
||
csum += buf[i];
|
||
*p++ = buf[i];
|
||
}
|
||
*p++ = '#';
|
||
*p++ = tohex ((csum >> 4) & 0xf);
|
||
*p++ = tohex (csum & 0xf);
|
||
|
||
/* Send it over and over until we get a positive ack. */
|
||
|
||
while (1)
|
||
{
|
||
if (remote_debug)
|
||
{
|
||
*p = '\0';
|
||
printf ("Sending packet: %s...", buf2); fflush(stdout);
|
||
}
|
||
if (SERIAL_WRITE (remote_desc, buf2, p - buf2))
|
||
perror_with_name ("putpkt: write failed");
|
||
|
||
/* read until either a timeout occurs (-2) or '+' is read */
|
||
while (1)
|
||
{
|
||
ch = readchar ();
|
||
|
||
switch (ch)
|
||
{
|
||
case '+':
|
||
if (remote_debug)
|
||
printf("Ack\n");
|
||
return;
|
||
case SERIAL_TIMEOUT:
|
||
break; /* Retransmit buffer */
|
||
case SERIAL_ERROR:
|
||
perror_with_name ("putpkt: couldn't read ACK");
|
||
case SERIAL_EOF:
|
||
error ("putpkt: EOF while trying to read ACK");
|
||
default:
|
||
if (remote_debug)
|
||
printf ("%02X %c ", ch&0xFF, ch);
|
||
continue;
|
||
}
|
||
break; /* Here to retransmit */
|
||
}
|
||
}
|
||
}
|
||
|
||
/* Read a packet from the remote machine, with error checking,
|
||
and store it in BUF. BUF is expected to be of size PBUFSIZ.
|
||
If FOREVER, wait forever rather than timing out; this is used
|
||
while the target is executing user code. */
|
||
|
||
static void
|
||
getpkt (buf, forever)
|
||
char *buf;
|
||
int forever;
|
||
{
|
||
char *bp;
|
||
unsigned char csum;
|
||
int c = 0;
|
||
unsigned char c1, c2;
|
||
int retries = 0;
|
||
#define MAX_RETRIES 10
|
||
|
||
while (1)
|
||
{
|
||
/* This can loop forever if the remote side sends us characters
|
||
continuously, but if it pauses, we'll get a zero from readchar
|
||
because of timeout. Then we'll count that as a retry. */
|
||
|
||
c = readchar();
|
||
if (c > 0 && c != '$')
|
||
continue;
|
||
|
||
if (c == SERIAL_TIMEOUT)
|
||
{
|
||
if (forever)
|
||
continue;
|
||
if (++retries >= MAX_RETRIES)
|
||
if (remote_debug) 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 (remote_debug)
|
||
puts_filtered ("Timeout in mid-packet, retrying\n");
|
||
goto whole; /* Start a new packet, count retries */
|
||
}
|
||
if (c == '$')
|
||
{
|
||
if (remote_debug)
|
||
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 (remote_debug)
|
||
fprintf (stderr,"Packet received: %s\n", buf);
|
||
}
|
||
|
||
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). */
|
||
|
||
static 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;
|
||
}
|
||
|
||
static 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);
|
||
}
|
||
#endif
|