/* Remote target communications for serial-line targets in custom GDB protocol
- Copyright 1988, 1991, 1992, 1993, 1994 Free Software Foundation, Inc.
+ Copyright 1988, 1991, 1992, 1993, 1994, 1995 Free Software Foundation, Inc.
This file is part of GDB.
- - if CSUM is incorrect
<data> is as follows:
- All values are encoded in ascii hex digits.
+ Most values are encoded in ascii hex digits. Signal numbers are according
+ to the numbering in target.h.
Request Packet
+ set thread Hct... Set thread for subsequent operations.
+ c = 'c' for thread used in step and
+ continue; t... can be -1 for all
+ threads.
+ c = 'g' for thread used in other
+ operations. If zero, pick a thread,
+ any thread.
+ reply OK for success
+ ENN for an error.
+
read registers g
reply XX....X Each byte of register data
is described by two hex digits.
where only part of the data was
written).
- cont cAA..AA AA..AA is address to resume
+ continue cAA..AA AA..AA is address to resume
If AA..AA is omitted,
resume at same address.
If AA..AA is omitted,
resume at same address.
+ continue with Csig;AA Continue with signal sig (hex signal
+ signal number).
+
+ step with Ssig;AA Like 'C' but step not continue.
+ signal
+
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
There is no immediate reply to step or cont.
The reply comes when the machine stops.
- It is SAA AA is the "signal number"
+ It is SAA AA is the signal number.
- or... TAAn...:r...;n:r...;n...:r...;
+ or... TAAn...:r...;n...:r...;n...:r...;
AA = signal number
- n... = register number
- r... = register contents
+ n... = register number (hex)
+ r... = register contents
+ n... = `thread'
+ r... = thread process ID. This is
+ a hex integer.
+ n... = other string not starting
+ with valid hex digit.
+ gdb should ignore this n,r pair
+ and go on to the next. This way
+ we can extend the protocol.
or... WAA The process exited, and AA is
the exit status. This is only
applicable for certains sorts of
targets.
+ or... XAA The process terminated with signal
+ AA.
+ or... Otext Send text to stdout. This can happen
+ at any time while the program is
+ running and the debugger should
+ continue to wait for 'W', 'T', etc.
+
kill request k
toggle debug d toggle debug flag (see 386 & 68k stubs)
general set QXXXX=yyyy Set value of XXXX to yyyy.
query sect offs qOffsets Get section offsets. Reply is
Text=xxx;Data=yyy;Bss=zzz
- console output Otext Send text to stdout. Only comes from
- remote target.
Responses can be run-length encoded to save space. A '*' means that
- the next two characters are hex digits giving a repeat count which
+ the next character is an ASCII encoding giving a repeat count which
stands for that many repititions of the character preceding the '*'.
- Note that this means that responses cannot contain '*'. Example:
- "0*03" means the same as "0000". */
+ The encoding is n+29, yielding a printable character where n >=3
+ (which is where rle starts to win). Don't use an n > 126.
+
+ So
+ "0* " means the same as "0000". */
#include "defs.h"
#include <string.h>
#include "gdbcmd.h"
#include "objfiles.h"
#include "gdb-stabs.h"
+#include "thread.h"
#include "dcache.h"
/* Prototypes for local functions */
-static int
-remote_write_bytes PARAMS ((CORE_ADDR memaddr, unsigned char *myaddr, int len));
+static int remote_write_bytes PARAMS ((CORE_ADDR memaddr,
+ char *myaddr, int len));
-static int
-remote_read_bytes PARAMS ((CORE_ADDR memaddr, unsigned char *myaddr, int len));
+static int remote_read_bytes PARAMS ((CORE_ADDR memaddr,
+ char *myaddr, int len));
-static void
-remote_files_info PARAMS ((struct target_ops *ignore));
+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 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_prepare_to_store PARAMS ((void));
-static void
-remote_fetch_registers PARAMS ((int regno));
+static void remote_fetch_registers PARAMS ((int regno));
-static void
-remote_resume PARAMS ((int pid, int step, enum target_signal siggnal));
+static void remote_resume PARAMS ((int pid, int step,
+ enum target_signal siggnal));
-static int
-remote_start_remote PARAMS ((char *dummy));
+static int remote_start_remote PARAMS ((char *dummy));
-static void
-remote_open PARAMS ((char *name, int from_tty));
+static void remote_open PARAMS ((char *name, int from_tty));
-static void
-remote_close PARAMS ((int quitting));
+static void remote_close PARAMS ((int quitting));
-static void
-remote_store_registers PARAMS ((int regno));
+static void remote_store_registers PARAMS ((int regno));
-static void
-getpkt PARAMS ((char *buf, int forever));
+static void getpkt PARAMS ((char *buf, int forever));
-static void
-putpkt PARAMS ((char *buf));
+static int putpkt PARAMS ((char *buf));
-static void
-remote_send PARAMS ((char *buf));
+static void remote_send PARAMS ((char *buf));
-static int
-readchar PARAMS ((int timeout));
+static int readchar PARAMS ((int timeout));
static int remote_wait PARAMS ((int pid, struct target_waitstatus *status));
-static int
-tohex PARAMS ((int nib));
+static void remote_kill PARAMS ((void));
-static int
-fromhex PARAMS ((int a));
+static int tohex PARAMS ((int nib));
-static void
-remote_detach PARAMS ((char *args, int from_tty));
+static int fromhex PARAMS ((int a));
-static void
-remote_interrupt PARAMS ((int signo));
+static void remote_detach PARAMS ((char *args, int from_tty));
-static void
-remote_interrupt_twice PARAMS ((int signo));
+static void remote_interrupt PARAMS ((int signo));
-static void
-interrupt_query PARAMS ((void));
+static void remote_interrupt_twice PARAMS ((int signo));
+
+static void interrupt_query PARAMS ((void));
extern struct target_ops remote_ops; /* Forward decl */
Unless this is going though some terminal server or multiplexer or
other form of hairy serial connection, I would think 2 seconds would
be plenty. */
-static int remote_timeout = 2;
-#if 0
-int icache;
-#endif
+static int remote_timeout = 2;
/* Descriptor for I/O to remote machine. Initialize it to NULL so that
remote_open knows that we don't have a file open when the program
doesn't support 'P', the only consequence is some unnecessary traffic. */
static int stub_supports_P = 1;
+\f
+/* These are the threads which we last sent to the remote system. -1 for all
+ or -2 for not sent yet. */
+int general_thread;
+int cont_thread;
+
+static void
+set_thread (th, gen)
+ int th;
+ int gen;
+{
+ char buf[PBUFSIZ];
+ int state = gen ? general_thread : cont_thread;
+ if (state == th)
+ return;
+ buf[0] = 'H';
+ buf[1] = gen ? 'g' : 'c';
+ if (th == 42000)
+ {
+ buf[2] = '0';
+ buf[3] = '\0';
+ }
+ else if (th < 0)
+ sprintf (&buf[2], "-%x", -th);
+ else
+ sprintf (&buf[2], "%x", th);
+ putpkt (buf);
+ getpkt (buf, 0);
+ if (gen)
+ general_thread = th;
+ else
+ cont_thread = th;
+}
+\f
+/* Return nonzero if the thread TH is still alive on the remote system. */
+
+static int
+remote_thread_alive (th)
+ int th;
+{
+ char buf[PBUFSIZ];
+
+ buf[0] = 'T';
+ if (th < 0)
+ sprintf (&buf[1], "-%x", -th);
+ else
+ sprintf (&buf[1], "%x", th);
+ putpkt (buf);
+ getpkt (buf, 0);
+ return (buf[0] == 'O' && buf[1] == 'K');
+}
\f
/* Clean up connection to a remote debugger. */
static void
get_offsets ()
{
- unsigned char buf[PBUFSIZ];
+ char buf[PBUFSIZ];
int nvals;
CORE_ADDR text_addr, data_addr, bss_addr;
struct section_offsets *offs;
+ symfile_objfile->num_sections
* sizeof (offs->offsets));
- /* FIXME: This code assumes gdb-stabs.h is being used; it's broken
- for xcoff, dwarf, sdb-coff, etc. But there is no simple
- canonical representation for this stuff. (Just what does "text"
- as seen by the stub mean, anyway? I think it means all sections
- with SEC_CODE set, but we currently have no way to deal with that). */
-
ANOFFSET (offs, SECT_OFF_TEXT) = text_addr;
/* This is a temporary kludge to force data and bss to use the same offsets
immediate_quit = 1; /* Allow user to interrupt it */
/* Ack any packet which the remote side has already sent. */
-
SERIAL_WRITE (remote_desc, "+", 1);
+ /* Let the stub know that we want it to return the thread. */
+ set_thread (-1, 0);
+
get_offsets (); /* Get text, data & bss offsets */
putpkt ("?"); /* initiate a query from remote machine */
immediate_quit = 0;
start_remote (); /* Initialize gdb process mechanisms */
-
return 1;
}
int from_tty;
{
if (name == 0)
- error (
-"To open a remote debug connection, you need to specify what serial\n\
+ 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);
}
}
+
SERIAL_RAW (remote_desc);
/* If there is something sitting in the buffer we might take it as a
stub to another, we can (if the target is closed and reopened) cope. */
stub_supports_P = 1;
+ general_thread = -2;
+ cont_thread = -2;
+
+ /* Without this, some commands which require an active target (such as kill)
+ won't work. This variable serves (at least) double duty as both the pid
+ of the target process (if it has such), and as a flag indicating that a
+ target is active. These functions should be split out into seperate
+ variables, especially since GDB will someday have a notion of debugging
+ several processes. */
+
+ inferior_pid = 42000;
/* 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))
+ "Couldn't establish connection to remote target\n", RETURN_MASK_ALL))
pop_target();
}
else if (a >= 'a' && a <= 'f')
return a - 'a' + 10;
else
- error ("Reply contains invalid hex digit");
+ error ("Reply contains invalid hex digit %d", a);
}
/* Convert number NIB to a hex digit. */
\f
/* Tell the remote machine to resume. */
+static enum target_signal last_sent_signal = TARGET_SIGNAL_0;
+int last_sent_step;
+
static void
remote_resume (pid, step, siggnal)
int pid, step;
{
char buf[PBUFSIZ];
- if (siggnal)
- {
- target_terminal_ours_for_output ();
- printf_filtered
- ("Can't send signals to a remote system. %s not sent.\n",
- target_signal_to_name (siggnal));
- target_terminal_inferior ();
- }
+ if (pid == -1)
+ set_thread (inferior_pid, 0);
+ else
+ set_thread (pid, 0);
dcache_flush (remote_dcache);
- strcpy (buf, step ? "s": "c");
+ last_sent_signal = siggnal;
+ last_sent_step = step;
+
+ if (siggnal != TARGET_SIGNAL_0)
+ {
+ buf[0] = step ? 'S' : 'C';
+ buf[1] = tohex (((int)siggnal >> 4) & 0xf);
+ buf[2] = tohex ((int)siggnal & 0xf);
+ buf[3] = '\0';
+ }
+ else
+ strcpy (buf, step ? "s": "c");
putpkt (buf);
}
target_terminal_inferior ();
}
+/* If nonzero, ignore the next kill. */
+int kill_kludge;
+
/* 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
struct target_waitstatus *status;
{
unsigned char buf[PBUFSIZ];
+ int thread_num = -1;
status->kind = TARGET_WAITKIND_EXITED;
status->value.integer = 0;
while (*p)
{
unsigned char *p1;
+ char *p_temp;
- regno = strtol (p, &p1, 16); /* Read the register number */
+ regno = strtol (p, &p_temp, 16); /* Read the register number */
+ p1 = (unsigned char *)p_temp;
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;
+ p1 = (unsigned char *) strchr (p, ':');
+ if (p1 == NULL)
+ warning ("Malformed packet (missing colon): %s\n\
+Packet: '%s'\n",
+ p, buf);
+ if (strncmp (p, "thread", p1 - p) == 0)
+ {
+ thread_num = strtol (++p1, &p_temp, 16);
+ p = (unsigned char *)p_temp;
+ }
+ }
+ else
+ {
+ p = p1;
+
+ if (*p++ != ':')
+ warning ("Malformed packet (missing colon): %s\n\
+Packet: '%s'\n",
+ p, buf);
+
+ if (regno >= NUM_REGS)
+ warning ("Remote sent bad register number %d: %s\n\
+Packet: '%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;
+ }
+ supply_register (regno, regs);
}
if (*p++ != ';')
warning ("Remote register badly formatted: %s", buf);
-
- supply_register (regno, regs);
}
}
/* fall through */
status->value.sig = (enum target_signal)
(((fromhex (buf[1])) << 4) + (fromhex (buf[2])));
- return 0;
+ goto got_status;
case 'W': /* Target exited */
{
/* The remote process exited. */
status->kind = TARGET_WAITKIND_EXITED;
status->value.integer = (fromhex (buf[1]) << 4) + fromhex (buf[2]);
- return 0;
+ goto got_status;
}
+ case 'X':
+ status->kind = TARGET_WAITKIND_SIGNALLED;
+ status->value.sig = (enum target_signal)
+ (((fromhex (buf[1])) << 4) + (fromhex (buf[2])));
+ kill_kludge = 1;
+
+ goto got_status;
case 'O': /* Console output */
- fputs_filtered (buf + 1, gdb_stdout);
+ fputs_filtered ((char *)(buf + 1), gdb_stdout);
continue;
+ case '\0':
+ if (last_sent_signal != TARGET_SIGNAL_0)
+ {
+ /* Zero length reply means that we tried 'S' or 'C' and
+ the remote system doesn't support it. */
+ target_terminal_ours_for_output ();
+ printf_filtered
+ ("Can't send signals to this remote system. %s not sent.\n",
+ target_signal_to_name (last_sent_signal));
+ last_sent_signal = TARGET_SIGNAL_0;
+ target_terminal_inferior ();
+
+ strcpy (buf, last_sent_step ? "s" : "c");
+ putpkt (buf);
+ continue;
+ }
+ /* else fallthrough */
default:
warning ("Invalid remote reply: %s", buf);
continue;
}
}
- return 0;
+ got_status:
+ if (thread_num != -1)
+ {
+ /* Initial thread value can only be acquired via wait, so deal with
+ this marker which is used before the first thread value is
+ acquired. */
+ if (inferior_pid == 42000)
+ {
+ inferior_pid = thread_num;
+ add_thread (inferior_pid);
+ }
+ return thread_num;
+ }
+ return inferior_pid;
}
/* Number of bytes of registers this stub implements. */
char *p;
char regs[REGISTER_BYTES];
+ set_thread (inferior_pid, 1);
+
sprintf (buf, "g");
remote_send (buf);
int i;
char *p;
+ set_thread (inferior_pid, 1);
+
if (regno >= 0 && stub_supports_P)
{
/* Try storing a single register. */
remote_send (buf);
}
-#if 0
-
-/* Use of the data cache is disabled because it loses for looking at
+/*
+ Use of the data cache *used* to be 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). */
+ would perhaps be one way to fix it. Another idea would be to use the
+ executable file for the text segment (for all SEC_CODE sections?
+ For all SEC_READONLY sections?). This has problems if you want to
+ actually see what the memory contains (e.g. self-modifying code,
+ clobbered memory, user downloaded the wrong thing).
+
+ Because it speeds so much up, it's now enabled, if you're playing
+ with registers you turn it of (set remotecache 0)
+*/
/* Read a word from remote address ADDR and return it.
This goes through the data cache. */
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);
}
{
dcache_poke (remote_dcache, addr, word);
}
-#endif /* 0 */
+
\f
/* Write memory data directly to the remote machine.
This does not inform the data cache; the data cache uses this.
static int
remote_write_bytes (memaddr, myaddr, len)
CORE_ADDR memaddr;
- unsigned char *myaddr;
+ char *myaddr;
int len;
{
char buf[PBUFSIZ];
static int
remote_read_bytes (memaddr, myaddr, len)
CORE_ADDR memaddr;
- unsigned char *myaddr;
+ char *myaddr;
int len;
{
char buf[PBUFSIZ];
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,
- (unsigned char *)myaddr, xfersize);
- else
- bytes_xferred = remote_read_bytes (memaddr,
- (unsigned char *)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;
+ return dcache_xfer_memory (remote_dcache, memaddr, myaddr, len, should_write);
}
+
#if 0
/* Enable after 4.12. */
remote_send (buf)
char *buf;
{
-
putpkt (buf);
getpkt (buf, 0);
/* Send a packet to the remote machine, with error checking.
The data of the packet is in BUF. */
-static void
+static int
putpkt (buf)
char *buf;
{
char buf2[PBUFSIZ];
int cnt = strlen (buf);
int ch;
+ int tcount = 0;
char *p;
/* Copy the packet into buffer BUF2, encapsulating it
{
ch = readchar (remote_timeout);
- if (remote_debug)
+ if (remote_debug)
{
switch (ch)
{
case '$':
if (started_error_output)
{
- putc_unfiltered ('\n');
+ putchar_unfiltered ('\n');
started_error_output = 0;
}
}
case '+':
if (remote_debug)
printf_unfiltered("Ack\n");
- return;
+ return 1;
case SERIAL_TIMEOUT:
+ tcount ++;
+ if (tcount > 3)
+ return 0;
break; /* Retransmit buffer */
case '$':
{
- unsigned char junkbuf[PBUFSIZ];
+ char junkbuf[PBUFSIZ];
/* It's probably an old response, and we're out of sync. Just
gobble up the packet and ignore it. */
started_error_output = 1;
printf_unfiltered ("putpkt: Junk: ");
}
- putc_unfiltered (ch & 0177);
+ putchar_unfiltered (ch & 0177);
}
continue;
}
if (csum == pktcsum)
return 1;
- printf_filtered ("Bad checksum, sentsum=0x%x, csum=0x%x, buf=",
- pktcsum, csum);
- puts_filtered (buf);
- puts_filtered ("\n");
-
+ if (remote_debug)
+ {
+ printf_filtered ("Bad checksum, sentsum=0x%x, csum=0x%x, buf=",
+ pktcsum, csum);
+ puts_filtered (buf);
+ puts_filtered ("\n");
+ }
return 0;
}
case '*': /* Run length encoding */
+ csum += c;
c = readchar (remote_timeout);
csum += c;
c = c - ' ' + 3; /* Compute repeat count */
- if (bp + c - 1 < buf + PBUFSIZ - 1)
+
+ if (c > 0 && c < 255 && bp + c - 1 < buf + PBUFSIZ - 1)
{
memset (bp, *(bp - 1), c);
bp += c;
printf_filtered ("Repeat count %d too large for buffer: ", c);
puts_filtered (buf);
puts_filtered ("\n");
-
return 0;
+
default:
if (bp < buf + PBUFSIZ - 1)
{
int timeout;
int val;
+ strcpy (buf,"timeout");
+
if (forever)
- timeout = -1;
+ {
+#ifdef MAINTENANCE_CMDS
+ timeout = watchdog > 0 ? watchdog : -1;
+#else
+ timeout = -1;
+#endif
+ }
+
else
timeout = remote_timeout;
-#define MAX_TRIES 10
+#define MAX_TRIES 3
for (tries = 1; tries <= MAX_TRIES; tries++)
{
if (c == SERIAL_TIMEOUT)
{
+#ifdef MAINTENANCE_CMDS
+ if (forever) /* Watchdog went off. Kill the target. */
+ {
+ target_mourn_inferior ();
+ error ("Watchdog has expired. Target detached.\n");
+ }
+#endif
if (remote_debug)
puts_filtered ("Timed out.\n");
goto retry;
}
/* Try the whole thing again. */
-retry:
+ retry:
SERIAL_WRITE (remote_desc, "-", 1);
}
static void
remote_kill ()
{
- putpkt ("k");
+ /* For some mysterious reason, wait_for_inferior calls kill instead of
+ mourn after it gets TARGET_WAITKIND_SIGNALLED. Work around it. */
+ if (kill_kludge)
+ {
+ kill_kludge = 0;
+ target_mourn_inferior ();
+ return;
+ }
+
+ /* Use catch_errors so the user can quit from gdb even when we aren't on
+ speaking terms with the remote system. */
+ catch_errors (putpkt, "k", "", RETURN_MASK_ERROR);
+
/* 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 ();
remote_mourn, /* to_mourn_inferior */
0, /* to_can_run */
0, /* to_notice_signals */
+ remote_thread_alive, /* to_thread_alive */
+ 0, /* to_stop */
process_stratum, /* to_stratum */
NULL, /* to_next */
1, /* to_has_all_memory */