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
+ '$' or '#'
+
+ CSUM1 and CSUM2 are ascii hex representation of an 8-bit
+ checksum of <data>, the most significant nibble is sent first.
+ the hex digits 0-9,a-f are used.
+
+ Receiver responds with:
+
+ + - if CSUM is correct and ready for next packet
+ - - if CSUM is incorrect
+
+ <data> is as follows:
All values are encoded in ascii hex digits.
Request Packet
read mem mAA..AA,LLLL AA..AA is address, LLLL is length.
reply XX..XX XX..XX is mem contents
+ Can be fewer bytes than requested
+ if able to read only part of the data.
or ENN NN is errno
write mem MAA..AA,LLLL:XX..XX
LLLL is number of bytes,
XX..XX is data
reply OK for success
- ENN for an error
+ ENN for an error (this includes the case
+ where only part of the data was
+ written).
cont cAA..AA AA..AA is address to resume
If AA..AA is omitted,
The reply comes when the machine stops.
It is SAA AA is the "signal number"
- or... TAAPPPPPPPPFFFFFFFF
- where AA is the signal number,
- PPPPPPPP is the PC (PC_REGNUM), and
- FFFFFFFF is the frame ptr (FP_REGNUM).
-
- kill req k
+ or... TAAn...:r...;n:r...;n...:r...;
+ AA = signal number
+ n... = register number
+ r... = register contents
+
+ kill request k
+
+ toggle debug d toggle debug flag (see 386 & 68k stubs)
+ reset r reset -- see sparc stub.
+ reserved <other> On other requests, the stub should
+ ignore the request and send an empty
+ response ($#<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 <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 "dcache.h"
+
#if !defined(DONT_USE_REMOTE)
#ifdef USG
#include <sys/types.h>
/* Prototypes for local functions */
-static void
-remote_write_bytes PARAMS ((CORE_ADDR, char *, int));
+static int
+remote_write_bytes PARAMS ((CORE_ADDR memaddr, unsigned char *myaddr, int len));
-static void
-remote_read_bytes PARAMS ((CORE_ADDR, char *, int));
+static int
+remote_read_bytes PARAMS ((CORE_ADDR memaddr, unsigned char *myaddr, int len));
static void
-remote_files_info PARAMS ((struct target_ops *));
+remote_files_info PARAMS ((struct target_ops *ignore));
static int
-remote_xfer_memory PARAMS ((CORE_ADDR, char *, int, int, struct target_ops *));
+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));
+remote_fetch_registers PARAMS ((int regno));
static void
-remote_resume PARAMS ((int, int));
+remote_resume PARAMS ((int pid, int step, int siggnal));
static int
-remote_start_remote PARAMS ((char *));
+remote_start_remote PARAMS ((char *dummy));
static void
-remote_open PARAMS ((char *, int));
+remote_open PARAMS ((char *name, int from_tty));
static void
-remote_close PARAMS ((int));
+remote_close PARAMS ((int quitting));
static void
-remote_store_registers PARAMS ((int));
+remote_store_registers PARAMS ((int regno));
static void
-getpkt PARAMS ((char *, int));
+getpkt PARAMS ((char *buf, int forever));
static void
-putpkt PARAMS ((char *));
+putpkt PARAMS ((char *buf));
static void
-remote_send PARAMS ((char *));
+remote_send PARAMS ((char *buf));
static int
readchar PARAMS ((void));
static int
-remote_wait PARAMS ((WAITTYPE *));
+remote_wait PARAMS ((WAITTYPE *status));
static int
-tohex PARAMS ((int));
+tohex PARAMS ((int nib));
static int
-fromhex PARAMS ((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_detach PARAMS ((char *, int));
+remote_interrupt_twice PARAMS ((int signo));
extern struct target_ops remote_ops; /* Forward decl */
-static int kiodebug = 0;
/* This was 5 seconds, which is a long time to sit and wait.
Unless this is going though some terminal server or multiplexer or
other form of hairy serial connection, I would think 2 seconds would
int icache;
#endif
-/* Descriptor for I/O to remote machine. Initialize it to -1 so that
+/* 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
starts. */
serial_t remote_desc = NULL;
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
+ send an ack. */
SERIAL_WRITE (remote_desc, "+\r", 2);
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;
unpush_target (&remote_ops);
-#if 0
- dcache_init ();
-#endif
+ remote_dcache = dcache_init (remote_read_bytes, remote_write_bytes);
remote_desc = SERIAL_OPEN (name);
if (!remote_desc)
}
push_target (&remote_ops); /* Switch to using remote target now */
- /* Start the remote connection; if error (0), discard this target. */
- immediate_quit++; /* Allow user to interrupt it */
+ /* 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"))
+ "Couldn't establish connection to remote target\n", RETURN_MASK_ALL))
pop_target();
}
/* Tell the remote machine to resume. */
static void
-remote_resume (step, siggnal)
- int step, siggnal;
+remote_resume (pid, step, siggnal)
+ int pid, step, siggnal;
{
char buf[PBUFSIZ];
target_terminal_inferior ();
}
-#if 0
- dcache_flush ();
-#endif
+ dcache_flush (remote_dcache);
strcpy (buf, step ? "s": "c");
putpkt (buf);
}
\f
-static void remote_interrupt_twice PARAMS ((int));
-static void (*ofunc)();
-
/* Send ^C to target to halt it. Target will respond, and send us a
packet. */
-void remote_interrupt(signo)
+static void
+remote_interrupt (signo)
int signo;
{
/* If this doesn't work, try more severe steps. */
signal (signo, remote_interrupt_twice);
- if (kiodebug)
+ 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)
Give up (and stop debugging it)? "))
{
target_mourn_inferior ();
- return_to_top_level ();
+ return_to_top_level (RETURN_QUIT);
}
else
{
while (*p)
{
- regno = strtol (p, &p, 16); /* Read the register number */
+ 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++ != ':'
- || regno >= NUM_REGS)
- error ("Remote sent bad register number %s", buf);
+ 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 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. */
-int
+static int
remote_fetch_word (addr)
CORE_ADDR addr;
{
+#if 0
if (icache)
{
extern CORE_ADDR text_start, text_end;
return buffer;
}
}
- return dcache_fetch (addr);
+#endif
+ return dcache_fetch (remote_dcache, addr);
}
/* Write a word WORD into remote address ADDR.
This goes through the data cache. */
-void
+static void
remote_store_word (addr, word)
CORE_ADDR addr;
int word;
{
- dcache_poke (addr, word);
+ dcache_poke (remote_dcache, addr, word);
}
#endif /* 0 */
\f
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. */
+ LEN is the number of bytes.
-static void
+ Returns number of bytes transferred, or 0 for error. */
+
+static int
remote_write_bytes (memaddr, myaddr, len)
CORE_ADDR memaddr;
- char *myaddr;
+ unsigned char *myaddr;
int len;
{
char buf[PBUFSIZ];
}
*p = '\0';
- remote_send (buf);
+ 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. */
+ LEN is the number of bytes.
-static void
+ Returns number of bytes transferred, or 0 for error. */
+
+static int
remote_read_bytes (memaddr, myaddr, len)
CORE_ADDR memaddr;
- char *myaddr;
+ unsigned char *myaddr;
int len;
{
char buf[PBUFSIZ];
abort ();
sprintf (buf, "m%x,%x", memaddr, len);
- remote_send (buf);
+ 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. */
for (i = 0; i < len; i++)
{
if (p[0] == 0 || p[1] == 0)
- error ("Remote reply is too short: %s", buf);
+ /* 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;
}
\f
/* Read or write LEN bytes from inferior memory at MEMADDR, transferring
int should_write;
struct target_ops *target; /* ignored */
{
- int origlen = len;
int xfersize;
+ int bytes_xferred;
+ int total_xferred = 0;
+
while (len > 0)
{
if (len > MAXBUFBYTES)
xfersize = len;
if (should_write)
- remote_write_bytes(memaddr, myaddr, xfersize);
+ bytes_xferred = remote_write_bytes (memaddr, myaddr, xfersize);
else
- remote_read_bytes (memaddr, myaddr, xfersize);
- memaddr += xfersize;
- myaddr += xfersize;
- len -= xfersize;
+ 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 origlen; /* no error possible */
+ return total_xferred;
}
static void
remote_files_info (ignore)
-struct target_ops *ignore;
+ struct target_ops *ignore;
{
puts_filtered ("Debugging a target over a serial line.\n");
}
\f
-/*
-
-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
- '$' or '#'
-
- CSUM1 and CSUM2 are ascii hex representation of an 8-bit
- checksum of <data>, the most significant nibble is sent first.
- the hex digits 0-9,a-f are used.
-
-Receiver responds with:
-
- + - if CSUM is correct and ready for next packet
- - - if CSUM is incorrect
-
-*/
+/* Stuff for dealing with the packets which are part of this protocol.
+ See comment at top of file for details. */
/* Read a single character from the remote end, masking it down to 7 bits. */
while (1)
{
- if (kiodebug)
+ if (remote_debug)
{
*p = '\0';
printf ("Sending packet: %s...", buf2); fflush(stdout);
switch (ch)
{
case '+':
- if (kiodebug)
+ if (remote_debug)
printf("Ack\n");
return;
case SERIAL_TIMEOUT:
case SERIAL_EOF:
error ("putpkt: EOF while trying to read ACK");
default:
- if (kiodebug)
+ if (remote_debug)
printf ("%02X %c ", ch&0xFF, ch);
continue;
}
if (forever)
continue;
if (++retries >= MAX_RETRIES)
- if (kiodebug) puts_filtered ("Timed out.\n");
+ if (remote_debug) puts_filtered ("Timed out.\n");
goto out;
}
c = readchar ();
if (c == SERIAL_TIMEOUT)
{
- if (kiodebug)
+ if (remote_debug)
puts_filtered ("Timeout in mid-packet, retrying\n");
goto whole; /* Start a new packet, count retries */
}
if (c == '$')
{
- if (kiodebug)
+ if (remote_debug)
puts_filtered ("Saw new packet start in middle of old one\n");
goto whole; /* Start a new packet, count retries */
}
SERIAL_WRITE (remote_desc, "+", 1);
- if (kiodebug)
+ if (remote_debug)
fprintf (stderr,"Packet received: %s\n", buf);
}
\f
-/* 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)
+remote_kill ()
{
- 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;
+ 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 ();
}
-/* Return the int data at address ADDR in dcache block DC. */
-
-int
-dcache_value (db, addr)
- struct dcache_block *db;
- unsigned int addr;
+static void
+remote_mourn ()
{
- if (addr & 3)
- abort ();
- return (db->data[(addr>>2)&3]);
+ unpush_target (&remote_ops);
+ generic_mourn_inferior ();
}
+\f
+#ifdef REMOTE_BREAKPOINT
-/* 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;
+/* On some machines, e.g. 68k, we may use a different breakpoint instruction
+ than other targets. */
+static unsigned char break_insn[] = REMOTE_BREAKPOINT;
- remque (db);
- insque (db, &dcache_valid);
- return (db);
-}
+/* Check that it fits in BREAKPOINT_MAX bytes. */
+static unsigned char check_break_insn_size[BREAKPOINT_MAX] = REMOTE_BREAKPOINT;
-/* Return the contents of the word at address ADDR in the remote machine,
- using the data cache. */
+#else /* No REMOTE_BREAKPOINT. */
-int
-dcache_fetch (addr)
- CORE_ADDR addr;
-{
- register struct dcache_block *db;
+/* Same old breakpoint instruction. This code does nothing different
+ than mem-break.c. */
+static unsigned char break_insn[] = BREAKPOINT;
- 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));
-}
+#endif /* No REMOTE_BREAKPOINT. */
-/* Write the word at ADDR both in the data cache and in the remote machine. */
+/* 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). */
-dcache_poke (addr, data)
+static int
+remote_insert_breakpoint (addr, contents_cache)
CORE_ADDR addr;
- int data;
+ char *contents_cache;
{
- 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;
- }
+ int val;
- /* Modify the word in the cache. */
- db->data[(addr>>2)&3] = data;
+ val = target_read_memory (addr, contents_cache, sizeof break_insn);
- /* Send the changed word. */
- remote_write_bytes (addr, &data, 4);
-}
+ if (val == 0)
+ val = target_write_memory (addr, (char *)break_insn, sizeof break_insn);
-/* 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 */
-\f
-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 ();
+ return val;
}
-static void
-remote_mourn ()
+static int
+remote_remove_breakpoint (addr, contents_cache)
+ CORE_ADDR addr;
+ char *contents_cache;
{
- unpush_target (&remote_ops);
- generic_mourn_inferior ();
+ return target_write_memory (addr, contents_cache, sizeof break_insn);
}
\f
/* Define the target subroutine names */
remote_prepare_to_store, /* to_prepare_to_store */
remote_xfer_memory, /* to_xfer_memory */
remote_files_info, /* to_files_info */
- NULL, /* to_insert_breakpoint */
- NULL, /* to_remove_breakpoint */
+
+ 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 */
_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
projects / binutils.git / blobdiff