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-rw-r--r--gdb/remote-sds.c1278
1 files changed, 1278 insertions, 0 deletions
diff --git a/gdb/remote-sds.c b/gdb/remote-sds.c
new file mode 100644
index 0000000..80564a9
--- /dev/null
+++ b/gdb/remote-sds.c
@@ -0,0 +1,1278 @@
+/* Remote target communications for serial-line targets using SDS' protocol.
+ Copyright 1997 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
+
+/* This interface was written by studying the behavior of the SDS
+ monitor on an ADS 821/860 board, and by consulting the
+ documentation of the monitor that is available on Motorola's web
+ site. -sts 8/13/97 */
+
+#include "defs.h"
+#include "gdb_string.h"
+#include <fcntl.h>
+#include "frame.h"
+#include "inferior.h"
+#include "bfd.h"
+#include "symfile.h"
+#include "target.h"
+#include "wait.h"
+#include "gdbcmd.h"
+#include "objfiles.h"
+#include "gdb-stabs.h"
+#include "gdbthread.h"
+
+#include "dcache.h"
+
+#ifdef USG
+#include <sys/types.h>
+#endif
+
+#include <signal.h>
+#include "serial.h"
+
+/* Declarations of local functions. */
+
+static int sds_write_bytes PARAMS ((CORE_ADDR, char *, int));
+
+static int sds_read_bytes PARAMS ((CORE_ADDR, char *, int));
+
+static void sds_files_info PARAMS ((struct target_ops *ignore));
+
+static int sds_xfer_memory PARAMS ((CORE_ADDR, char *,
+ int, int, struct target_ops *));
+
+static void sds_prepare_to_store PARAMS ((void));
+
+static void sds_fetch_registers PARAMS ((int));
+
+static void sds_resume PARAMS ((int, int, enum target_signal));
+
+static int sds_start_remote PARAMS ((char *));
+
+static void sds_open PARAMS ((char *, int));
+
+static void sds_close PARAMS ((int));
+
+static void sds_store_registers PARAMS ((int));
+
+static void sds_mourn PARAMS ((void));
+
+static void sds_restart PARAMS ((void));
+
+static void sds_create_inferior PARAMS ((char *, char *, char **));
+
+static int getmessage PARAMS ((unsigned char *, int));
+
+static int putmessage PARAMS ((unsigned char *, int));
+
+static int sds_send PARAMS ((unsigned char *, int));
+
+static int readchar PARAMS ((int));
+
+static int sds_wait PARAMS ((int, struct target_waitstatus *));
+
+static void sds_kill PARAMS ((void));
+
+static int tohex PARAMS ((int));
+
+static int fromhex PARAMS ((int));
+
+static void sds_detach PARAMS ((char *, int));
+
+static void sds_interrupt PARAMS ((int));
+
+static void sds_interrupt_twice PARAMS ((int));
+
+static void interrupt_query PARAMS ((void));
+
+static int read_frame PARAMS ((char *));
+
+static int sds_insert_breakpoint PARAMS ((CORE_ADDR, char *));
+
+static int sds_remove_breakpoint PARAMS ((CORE_ADDR, char *));
+
+
+static struct target_ops sds_ops; /* Forward decl */
+
+/* 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
+ be plenty. */
+
+/* Changed to allow option to set timeout value.
+ was static int sds_timeout = 2; */
+static int sds_timeout = 2;
+
+/* This variable chooses whether to send a ^C or a break when the user
+ requests program interruption. Although ^C is usually what remote
+ systems expect, and that is the default here, sometimes a break is
+ preferable instead. */
+
+static int sds_break;
+
+/* Descriptor for I/O to remote machine. Initialize it to NULL so
+ that sds_open knows that we don't have a file open when the program
+ starts. */
+
+static serial_t sds_desc = NULL;
+
+/* Having this larger than 400 causes us to be incompatible with m68k-stub.c
+ and i386-stub.c. Normally, no one would notice because it only matters
+ for writing large chunks of memory (e.g. in downloads). Also, this needs
+ to be more than 400 if required to hold the registers (see below, where
+ we round it up based on REGISTER_BYTES). */
+#define PBUFSIZ 400
+
+/* 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. */
+/* The blank line after the #if seems to be required to work around a
+ bug in HP's PA compiler. */
+#if REGISTER_BYTES > MAXBUFBYTES
+
+#undef PBUFSIZ
+#define PBUFSIZ (REGISTER_BYTES * 2 + 32)
+#endif
+
+static int next_msg_id;
+
+static int just_started;
+
+static int message_pending;
+
+
+/* Restart the remote side; this is an extended protocol operation. */
+
+static void
+sds_restart ()
+{
+}
+
+/* Clean up connection to a remote debugger. */
+
+/* ARGSUSED */
+static void
+sds_close (quitting)
+ int quitting;
+{
+ if (sds_desc)
+ SERIAL_CLOSE (sds_desc);
+ sds_desc = NULL;
+}
+
+/* Stub for catch_errors. */
+
+static int
+sds_start_remote (dummy)
+ char *dummy;
+{
+ char c;
+ unsigned char buf[200];
+
+ immediate_quit = 1; /* Allow user to interrupt it */
+
+ /* Ack any packet which the remote side has already sent. */
+ SERIAL_WRITE (sds_desc, "{#*\r\n", 5);
+ SERIAL_WRITE (sds_desc, "{#}\r\n", 5);
+
+ while ((c = readchar (1)) >= 0)
+ printf_unfiltered ("%c");
+ printf_unfiltered ("\n");
+
+ next_msg_id = 251;
+
+ buf[0] = 26;
+ sds_send (buf, 1);
+
+ buf[0] = 0;
+ sds_send (buf, 1);
+
+ 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 *sds_dcache;
+
+static void
+sds_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 (&sds_ops);
+
+ sds_dcache = dcache_init (sds_read_bytes, sds_write_bytes);
+
+ sds_desc = SERIAL_OPEN (name);
+ if (!sds_desc)
+ perror_with_name (name);
+
+ if (baud_rate != -1)
+ {
+ if (SERIAL_SETBAUDRATE (sds_desc, baud_rate))
+ {
+ SERIAL_CLOSE (sds_desc);
+ perror_with_name (name);
+ }
+ }
+
+
+ SERIAL_RAW (sds_desc);
+
+ /* If there is something sitting in the buffer we might take it as a
+ response to a command, which would be bad. */
+ SERIAL_FLUSH_INPUT (sds_desc);
+
+ if (from_tty)
+ {
+ puts_filtered ("Remote debugging using ");
+ puts_filtered (name);
+ puts_filtered ("\n");
+ }
+ push_target (&sds_ops); /* Switch to using remote target now */
+
+ /* 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;
+
+ just_started = 1;
+
+ /* 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 (sds_start_remote, (char *)0,
+ "Couldn't establish connection to remote target\n",
+ RETURN_MASK_ALL))
+ pop_target ();
+}
+
+/* This takes a program previously attached to and detaches it. After
+ this is done, GDB can be used to debug some other program. We
+ better not have left any breakpoints in the target program or it'll
+ die when it hits one. */
+
+static void
+sds_detach (args, from_tty)
+ char *args;
+ int from_tty;
+{
+ char buf[PBUFSIZ];
+
+ if (args)
+ error ("Argument given to \"detach\" when remotely debugging.");
+
+#if 0
+ /* Tell the remote target to detach. */
+ strcpy (buf, "D");
+ sds_send (buf, 1);
+#endif
+
+ 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 %d", a);
+}
+
+/* Convert number NIB to a hex digit. */
+
+static int
+tohex (nib)
+ int nib;
+{
+ if (nib < 10)
+ return '0'+nib;
+ else
+ return 'a'+nib-10;
+}
+
+static int
+tob64 (inbuf, outbuf, len)
+ unsigned char *inbuf;
+ char *outbuf;
+ int len;
+{
+ int i, sum;
+
+ if (len % 3 != 0)
+ error ("bad length");
+
+ for (i = 0; i < len; i += 3)
+ {
+ /* Collect the next three bytes into a number. */
+ sum = ((long) *inbuf++) << 16;
+ sum |= ((long) *inbuf++) << 8;
+ sum |= ((long) *inbuf++);
+
+ /* Spit out 4 6-bit encodings. */
+ *outbuf++ = ((sum >> 18) & 0x3f) + '0';
+ *outbuf++ = ((sum >> 12) & 0x3f) + '0';
+ *outbuf++ = ((sum >> 6) & 0x3f) + '0';
+ *outbuf++ = (sum & 0x3f) + '0';
+ }
+}
+
+static int
+fromb64 (inbuf, outbuf, len)
+ char *inbuf, *outbuf;
+ int len;
+{
+ int i, sum;
+
+ if (len % 4 != 0)
+ error ("bad length");
+
+ for (i = 0; i < len; i += 4)
+ {
+ /* Collect 4 6-bit digits. */
+ sum = (*inbuf++ - '0') << 18;
+ sum |= (*inbuf++ - '0') << 12;
+ sum |= (*inbuf++ - '0') << 6;
+ sum |= (*inbuf++ - '0');
+
+ /* Now take the resulting 24-bit number and get three bytes out
+ of it. */
+ *outbuf++ = (sum >> 16) & 0xff;
+ *outbuf++ = (sum >> 8) & 0xff;
+ *outbuf++ = sum & 0xff;
+ }
+
+ return (len / 4) * 3;
+}
+
+
+/* Tell the remote machine to resume. */
+
+static enum target_signal last_sent_signal = TARGET_SIGNAL_0;
+int last_sent_step;
+
+static void
+sds_resume (pid, step, siggnal)
+ int pid, step;
+ enum target_signal siggnal;
+{
+ unsigned char buf[PBUFSIZ];
+
+ dcache_flush (sds_dcache);
+
+ last_sent_signal = siggnal;
+ last_sent_step = step;
+
+ buf[0] = (step ? 21 : 20);
+ buf[1] = 0; /* (should be signal?) */
+
+ sds_send (buf, 2);
+}
+
+/* Send ^C to target to halt it. Target will respond, and send us a
+ packet. */
+
+static void
+sds_interrupt (signo)
+ int signo;
+{
+ /* If this doesn't work, try more severe steps. */
+ signal (signo, sds_interrupt_twice);
+
+ if (remote_debug)
+ printf_unfiltered ("sds_interrupt called\n");
+
+ /* Send a break or a ^C, depending on user preference. */
+ if (sds_break)
+ SERIAL_SEND_BREAK (sds_desc);
+ else
+ SERIAL_WRITE (sds_desc, "\003", 1);
+}
+
+static void (*ofunc)();
+
+/* The user typed ^C twice. */
+static void
+sds_interrupt_twice (signo)
+ int signo;
+{
+ signal (signo, ofunc);
+
+ interrupt_query ();
+
+ signal (signo, sds_interrupt);
+}
+
+/* Ask the user what to do when an interrupt is received. */
+
+static void
+interrupt_query ()
+{
+ 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);
+ }
+
+ 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 means in the case of this target). */
+
+static int
+sds_wait (pid, status)
+ int pid;
+ struct target_waitstatus *status;
+{
+ unsigned char buf[PBUFSIZ];
+ int retlen;
+
+ status->kind = TARGET_WAITKIND_EXITED;
+ status->value.integer = 0;
+
+ ofunc = (void (*)()) signal (SIGINT, sds_interrupt);
+
+ signal (SIGINT, ofunc);
+
+ if (just_started)
+ {
+ just_started = 0;
+ status->kind = TARGET_WAITKIND_STOPPED;
+ return inferior_pid;
+ }
+
+ while (1)
+ {
+ getmessage (buf, 1);
+
+ if (message_pending)
+ {
+ buf[0] = 26;
+ retlen = sds_send (buf, 1);
+ message_pending = 0;
+ status->kind = TARGET_WAITKIND_STOPPED;
+ goto got_status;
+ }
+ }
+ got_status:
+ return inferior_pid;
+}
+
+/* Number of bytes of registers this stub implements. */
+static int register_bytes_found;
+
+/* Read the remote registers into the block REGS. */
+/* Currently we just read all the registers, so we don't use regno. */
+
+/* ARGSUSED */
+static void
+sds_fetch_registers (regno)
+ int regno;
+{
+ unsigned char buf[PBUFSIZ];
+ int i, len;
+ char *p;
+ char regs[REGISTER_BYTES];
+
+ /* Unimplemented registers read as all bits zero. */
+ memset (regs, 0, REGISTER_BYTES);
+
+ buf[0] = 18;
+ buf[1] = 2;
+ buf[2] = 0;
+ len = sds_send (buf, 3);
+
+ /* Reply describes registers byte by byte. Suck them all up, then
+ supply them to the register cacheing/storage mechanism. */
+
+ for (i = 0; i < len; i++)
+ regs[i] = buf[i];
+
+ buf[0] = 18;
+ buf[1] = 1;
+ buf[2] = 0;
+ len = sds_send (buf, 3);
+
+ for (i = 0; i < 4 * 6; i++)
+ {
+ regs[i + 4 * 32 + 8 * 32] = buf[i];
+ }
+
+ /* (should warn about reply too short) */
+
+ supply_them:
+ for (i = 0; i < NUM_REGS; i++)
+ supply_register (i, &regs[REGISTER_BYTE(i)]);
+}
+
+/* Prepare to store registers. Since we may send them all (using a
+ 'G' request), we have to read out the ones we don't want to change
+ first. */
+
+static void
+sds_prepare_to_store ()
+{
+ /* Make sure the entire registers array is valid. */
+ read_register_bytes (0, (char *)NULL, REGISTER_BYTES);
+}
+
+/* Store register REGNO, or all registers if REGNO == -1, from the contents
+ of REGISTERS. FIXME: ignores errors. */
+
+static void
+sds_store_registers (regno)
+ int regno;
+{
+ unsigned char buf[PBUFSIZ];
+ int i;
+ char *p;
+
+ buf[0] = 19;
+ buf[1] = 2;
+ buf[2] = 0;
+ buf[3] = 0;
+
+ p = buf + 4;
+
+ for (i = 0; i < 4 * 32; i++)
+ p[i] = registers[i];
+
+ sds_send (buf, 4 + 4 * 32);
+
+ buf[0] = 19;
+ buf[1] = 1;
+ buf[2] = 0;
+ buf[3] = 0;
+
+ p = buf + 4;
+
+ for (i = 0; i < 4 * 10; i++)
+ p[i] = registers[i];
+
+ sds_send (buf, 4 + 4 * 10);
+}
+
+/*
+ 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. 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. */
+
+#if 0 /* unused? */
+static int
+sds_fetch_word (addr)
+ CORE_ADDR addr;
+{
+ return dcache_fetch (sds_dcache, addr);
+}
+
+/* Write a word WORD into remote address ADDR.
+ This goes through the data cache. */
+
+static void
+sds_store_word (addr, word)
+ CORE_ADDR addr;
+ int word;
+{
+ dcache_poke (sds_dcache, addr, word);
+}
+#endif /* 0 (unused?) */
+
+
+/* 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
+sds_write_bytes (memaddr, myaddr, len)
+ CORE_ADDR memaddr;
+ char *myaddr;
+ int len;
+{
+ int max_buf_size; /* Max size of packet output buffer */
+ int origlen;
+ unsigned char buf[PBUFSIZ];
+ int todo;
+ int i;
+
+ /* Chop the transfer down if necessary */
+
+ max_buf_size = 150;
+
+ origlen = len;
+ while (len > 0)
+ {
+ todo = min (len, max_buf_size);
+
+ buf[0] = 13;
+ buf[1] = 0;
+ buf[2] = (int) (memaddr >> 24) & 0xff;
+ buf[3] = (int) (memaddr >> 16) & 0xff;
+ buf[4] = (int) (memaddr >> 8) & 0xff;
+ buf[5] = (int) (memaddr ) & 0xff;
+ buf[6] = 1;
+ buf[7] = 0;
+
+ for (i = 0; i < todo; i++)
+ buf[i + 8] = myaddr[i];
+
+ sds_send (buf, 8 + todo);
+
+ /* (should look at result) */
+
+ myaddr += todo;
+ memaddr += todo;
+ len -= todo;
+ }
+ return origlen;
+}
+
+/* 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
+sds_read_bytes (memaddr, myaddr, len)
+ CORE_ADDR memaddr;
+ char *myaddr;
+ int len;
+{
+ int max_buf_size; /* Max size of packet output buffer */
+ int origlen, retlen;
+ unsigned char buf[PBUFSIZ];
+ int todo;
+ int i;
+
+ /* Chop the transfer down if necessary */
+
+ max_buf_size = 150;
+
+ origlen = len;
+ while (len > 0)
+ {
+ todo = min (len, max_buf_size);
+
+ buf[0] = 12;
+ buf[1] = 0;
+ buf[2] = (int) (memaddr >> 24) & 0xff;
+ buf[3] = (int) (memaddr >> 16) & 0xff;
+ buf[4] = (int) (memaddr >> 8) & 0xff;
+ buf[5] = (int) (memaddr ) & 0xff;
+ buf[6] = (int) (todo >> 8) & 0xff;
+ buf[7] = (int) (todo ) & 0xff;
+ buf[8] = 1;
+
+ retlen = sds_send (buf, 9);
+
+ if (retlen - 2 != todo)
+ {
+ return 0;
+ }
+
+ /* Reply describes memory byte by byte. */
+
+ for (i = 0; i < todo; i++)
+ myaddr[i] = buf[i + 2];
+
+ myaddr += todo;
+ memaddr += todo;
+ len -= todo;
+ }
+
+ return origlen;
+}
+
+/* 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
+sds_xfer_memory(memaddr, myaddr, len, should_write, target)
+ CORE_ADDR memaddr;
+ char *myaddr;
+ int len;
+ int should_write;
+ struct target_ops *target; /* ignored */
+{
+ return dcache_xfer_memory (sds_dcache, memaddr, myaddr, len, should_write);
+}
+
+
+static void
+sds_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 (timeout)
+ int timeout;
+{
+ int ch;
+
+ ch = SERIAL_READCHAR (sds_desc, timeout);
+
+ if (remote_debug > 1 && ch >= 0)
+ printf_unfiltered("%c(%x)", ch, ch);
+
+ switch (ch)
+ {
+ case SERIAL_EOF:
+ error ("Remote connection closed");
+ case SERIAL_ERROR:
+ perror_with_name ("Remote communication error");
+ case SERIAL_TIMEOUT:
+ return ch;
+ default:
+ return ch & 0x7f;
+ }
+}
+
+static int
+compute_checksum (csum, buf, len)
+ int csum, len;
+ char *buf;
+{
+ int i;
+
+ for (i = 0; i < len; ++i)
+ csum += (unsigned char) buf[i];
+
+ csum %= 253;
+ return csum;
+}
+
+/* Send the command in BUF to the remote machine, and read the reply
+ into BUF also. */
+
+static int
+sds_send (buf, len)
+ unsigned char *buf;
+ int len;
+{
+ putmessage (buf, len);
+
+ return getmessage (buf, 0);
+}
+
+/* Send a message to the remote machine. */
+
+static int
+putmessage (buf, len)
+ unsigned char *buf;
+ int len;
+{
+ int i;
+ unsigned char csum = 0;
+ char buf2[PBUFSIZ], buf3[PBUFSIZ];
+ unsigned char header[3];
+ int ch;
+ int tcount = 0;
+ char *p;
+
+ /* Copy the packet into buffer BUF2, encapsulating it
+ and giving it a checksum. */
+
+ if (len > (int) sizeof (buf2) - 5) /* Prosanity check */
+ abort();
+
+ if (remote_debug)
+ {
+ fprintf_unfiltered (gdb_stderr, "Message to send: \"");
+ for (i = 0; i < len; ++i)
+ fprintf_unfiltered (gdb_stderr, "%02x", buf[i]);
+ fprintf_unfiltered (gdb_stderr, "\"\n");
+ }
+
+ p = buf2;
+ *p++ = '$';
+
+ header[1] = next_msg_id;
+
+ if (len % 3 != 0)
+ {
+ buf[len] = '\0';
+ buf[len+1] = '\0';
+ }
+
+ len = ((len + 2) / 3) * 3;
+
+ header[2] = len;
+
+ csum = compute_checksum (csum, buf, len);
+ csum = compute_checksum (csum, header+1, 2);
+
+ header[0] = csum;
+
+ tob64 (header, p, 3);
+ p += 4;
+ tob64 (buf, buf3, len);
+
+ for (i = 0; i < (len / 3) * 4; i++)
+ {
+ *p++ = buf3[i];
+ }
+ *p++ = '\r';
+ *p++ = '\n';
+
+ next_msg_id = (next_msg_id + 3) % 245;
+
+ /* Send it over and over until we get a positive ack. */
+
+ while (1)
+ {
+ int started_error_output = 0;
+
+ if (remote_debug)
+ {
+ *p = '\0';
+ printf_unfiltered ("Sending encoded: \"%s\"", buf2);
+ printf_unfiltered (" (Checksum %d, id %d, length %d)\n",
+ header[0], header[1], header[2]);
+ gdb_flush (gdb_stdout);
+ }
+ if (SERIAL_WRITE (sds_desc, buf2, p - buf2))
+ perror_with_name ("putmessage: write failed");
+
+ return 1;
+
+ }
+
+}
+
+/* Come here after finding the start of the frame. Collect the rest
+ into BUF. Returns 0 on any error, 1 on success. */
+
+static int
+read_frame (buf)
+ char *buf;
+{
+ char *bp;
+ int c;
+
+ bp = buf;
+
+ while (1)
+ {
+ c = readchar (sds_timeout);
+
+ switch (c)
+ {
+ case SERIAL_TIMEOUT:
+ if (remote_debug)
+ puts_filtered ("Timeout in mid-message, retrying\n");
+ return 0;
+ case '$':
+ if (remote_debug)
+ puts_filtered ("Saw new packet start in middle of old one\n");
+ return 0; /* Start a new packet, count retries */
+ case '\r':
+ break;
+
+ case '\n':
+ {
+ *bp = '\000';
+ if (remote_debug)
+ printf_filtered ("Received encoded: \"%s\"\n", buf);
+ return 1;
+ }
+
+ default:
+ if (bp < buf + PBUFSIZ - 1)
+ {
+ *bp++ = c;
+ continue;
+ }
+
+ *bp = '\0';
+ puts_filtered ("Message too long: ");
+ puts_filtered (buf);
+ puts_filtered ("\n");
+
+ return 0;
+ }
+ }
+}
+
+/* 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 int
+getmessage (buf, forever)
+ unsigned char *buf;
+ int forever;
+{
+ int c, c2, c3;
+ int tries;
+ int timeout;
+ int val, i, len, csum;
+ unsigned char header[3];
+ unsigned char inbuf[500];
+
+ strcpy (buf, "timeout");
+
+ if (forever)
+ {
+#ifdef MAINTENANCE_CMDS
+ timeout = watchdog > 0 ? watchdog : -1;
+#else
+ timeout = -1;
+#endif
+ }
+
+ else
+ timeout = sds_timeout;
+
+#define MAX_TRIES 3
+
+ for (tries = 1; tries <= MAX_TRIES; tries++)
+ {
+ /* 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. */
+
+ /* Note that we will only wait forever prior to the start of a packet.
+ After that, we expect characters to arrive at a brisk pace. They
+ should show up within sds_timeout intervals. */
+
+ do
+ {
+ c = readchar (timeout);
+
+ 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;
+ }
+ }
+ while (c != '$' && c != '{');
+
+ /* We might have seen a "trigraph", a sequence of three characters
+ that indicate various sorts of communication state. */
+
+ if (c == '{')
+ {
+ /* Read the other two chars of the trigraph. */
+ c2 = readchar (timeout);
+ c3 = readchar (timeout);
+ if (remote_debug)
+ fprintf_unfiltered (gdb_stderr, "Trigraph %c%c%c received\n",
+ c, c2, c3);
+ if (c3 == '+')
+ {
+ message_pending = 1;
+ return;
+ }
+ continue;
+ }
+
+ val = read_frame (inbuf);
+
+ if (val == 1)
+ {
+ fromb64 (inbuf, header, 4);
+ /* (should check out other bits) */
+ fromb64 (inbuf + 4, buf, strlen (inbuf) - 4);
+
+ len = header[2];
+
+ csum = 0;
+ csum = compute_checksum (csum, buf, len);
+ csum = compute_checksum (csum, header + 1, 2);
+
+ if (csum != header[0])
+ fprintf_unfiltered (gdb_stderr,
+ "Checksum mismatch: computed %d, received %d\n",
+ csum, header[0]);
+
+ if (header[2] == 0xff)
+ fprintf_unfiltered (gdb_stderr, "Requesting resend...\n");
+
+ if (remote_debug)
+ {
+ fprintf_unfiltered (gdb_stderr,
+ "... (Got checksum %d, id %d, length %d)\n",
+ header[0], header[1], header[2]);
+ fprintf_unfiltered (gdb_stderr, "Message received: \"");
+ for (i = 0; i < len; ++i)
+ {
+ fprintf_unfiltered (gdb_stderr, "%02x", (unsigned char) buf[i]);
+ }
+ fprintf_unfiltered (gdb_stderr, "\"\n");
+ }
+
+ /* no ack required? */
+ return len;
+ }
+
+ /* Try the whole thing again. */
+ retry:
+ /* need to do something here */
+ }
+
+ /* We have tried hard enough, and just can't receive the packet. Give up. */
+
+ printf_unfiltered ("Ignoring packet error, continuing...\n");
+}
+
+static void
+sds_kill ()
+{
+ /* 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;
+ }
+
+#if 0 /* fix to use 1-arg fn */
+ /* Use catch_errors so the user can quit from gdb even when we aren't on
+ speaking terms with the remote system. */
+ catch_errors (putmessage, "k", "", RETURN_MASK_ERROR);
+#endif
+
+ /* 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
+sds_mourn ()
+{
+ unpush_target (&sds_ops);
+ generic_mourn_inferior ();
+}
+
+static void
+sds_create_inferior (exec_file, args, env)
+ char *exec_file;
+ char *args;
+ char **env;
+{
+ /* Rip out the breakpoints; we'll reinsert them after restarting
+ the remote server. */
+ remove_breakpoints ();
+
+ /* Now restart the remote server. */
+ sds_restart ();
+
+ /* Now put the breakpoints back in. This way we're safe if the
+ restart function works via a unix fork on the remote side. */
+ insert_breakpoints ();
+
+ /* Clean up from the last time we were running. */
+ clear_proceed_status ();
+
+ /* Let the remote process run. */
+ proceed (-1, TARGET_SIGNAL_0, 0);
+}
+
+
+/* The SDS monitor has commands for breakpoint insertion, although it
+ it doesn't actually manage the breakpoints, it just returns the
+ replaced instruction back to the debugger. */
+
+static int
+sds_insert_breakpoint (addr, contents_cache)
+ CORE_ADDR addr;
+ char *contents_cache;
+{
+ int retlen;
+ unsigned char buf[PBUFSIZ];
+
+ buf[0] = 16;
+ buf[1] = 0;
+
+ retlen = sds_send (buf, 7);
+}
+
+static int
+sds_remove_breakpoint (addr, contents_cache)
+ CORE_ADDR addr;
+ char *contents_cache;
+{
+ int retlen;
+ unsigned char buf[PBUFSIZ];
+
+ buf[0] = 17;
+ buf[1] = 0;
+
+ retlen = sds_send (buf, 7);
+}
+
+/* Define the target operations vector. */
+
+static struct target_ops sds_ops =
+{
+ "sds", /* to_shortname */
+ "Remote serial target with SDS protocol", /* to_longname */
+ "Use a remote computer via a serial line, using the SDS protocol.\n\
+Specify the serial device it is connected to (e.g. /dev/ttya).", /* to_doc */
+ sds_open, /* to_open */
+ sds_close, /* to_close */
+ NULL, /* to_attach */
+ sds_detach, /* to_detach */
+ sds_resume, /* to_resume */
+ sds_wait, /* to_wait */
+ sds_fetch_registers, /* to_fetch_registers */
+ sds_store_registers, /* to_store_registers */
+ sds_prepare_to_store, /* to_prepare_to_store */
+ sds_xfer_memory, /* to_xfer_memory */
+ sds_files_info, /* to_files_info */
+ sds_insert_breakpoint, /* to_insert_breakpoint */
+ sds_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 */
+ sds_kill, /* to_kill */
+ generic_load, /* to_load */
+ NULL, /* to_lookup_symbol */
+ sds_create_inferior, /* to_create_inferior */
+ sds_mourn, /* to_mourn_inferior */
+ 0, /* to_can_run */
+ 0, /* to_notice_signals */
+ 0, /* to_thread_alive */
+ 0, /* to_stop */
+ 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 */
+};
+
+/* Put a command string, in args, out to the monitor and display the
+ reply message. */
+
+static void
+sds_command (args, from_tty)
+ char *args;
+ int from_tty;
+{
+ char *p;
+ int i, len, resp_len;
+ unsigned char buf[1000];
+
+ /* Convert hexadecimal chars into a byte buffer. */
+ p = args;
+ len = 0;
+ while (*p != '\0')
+ {
+ buf[len++] = fromhex (p[0]) * 16 + fromhex (p[1]);
+ if (p[1] == '\0')
+ break;
+ p += 2;
+ }
+
+ len = sds_send (buf, len);
+
+ printf_filtered ("Reply is ");
+ for (i = 0; i < len; ++i)
+ {
+ printf_filtered ("%02x", buf[i]);
+ }
+ printf_filtered ("\n");
+}
+
+void
+_initialize_remote_sds ()
+{
+ add_target (&sds_ops);
+
+ add_show_from_set (add_set_cmd ("sdstimeout", no_class,
+ var_integer, (char *)&sds_timeout,
+ "Set timeout value for sds read.\n", &setlist),
+ &showlist);
+
+ add_com ("sds", class_obscure, sds_command,
+ "Send a command to the SDS monitor.");
+}