[openocd.git] / src / server / gdb_server.c

/***************************************************************************
 *   Copyright (C) 2005 by Dominic Rath                                    *
 *   Dominic.Rath@gmx.de                                                   *
 *                                                                         *
 *   Copyright (C) 2007,2008 Øyvind Harboe                                 *
 *   oyvind.harboe@zylin.com                                               *
 *                                                                         *
 *   Copyright (C) 2008 by Spencer Oliver                                  *
 *   spen@spen-soft.co.uk                                                  *
 *                                                                         *
 *   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.             *
 ***************************************************************************/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include "gdb_server.h"
#include "target_request.h"
#include "register.h"
#include "server.h"
#include "flash.h"
#include "image.h"
#include "jtag.h"


#if 0
#define _DEBUG_GDB_IO_
#endif

static int gdb_breakpoint_override;
static enum breakpoint_type gdb_breakpoint_override_type;

extern int gdb_error(connection_t *connection, int retval);
static unsigned short gdb_port;
static const char *DIGITS = "0123456789abcdef";

static void gdb_log_callback(void *priv, const char *file, int line,
                const char *function, const char *string);

enum gdb_detach_mode
{
        GDB_DETACH_RESUME,
        GDB_DETACH_RESET,
        GDB_DETACH_HALT,
        GDB_DETACH_NOTHING
};

/* target behaviour on gdb detach */
enum gdb_detach_mode detach_mode = GDB_DETACH_RESUME;

/* set if we are sending a memory map to gdb
 * via qXfer:memory-map:read packet */
/* enabled by default*/
int gdb_use_memory_map = 1;
/* enabled by default*/
int gdb_flash_program = 1;

/* if set, data aborts cause an error to be reported in memory read packets
 * see the code in gdb_read_memory_packet() for further explanations */
int gdb_report_data_abort = 0;

int gdb_last_signal(target_t *target)
{
        switch (target->debug_reason)
        {
                case DBG_REASON_DBGRQ:
                        return 0x2; /* SIGINT */
                case DBG_REASON_BREAKPOINT:
                case DBG_REASON_WATCHPOINT:
                case DBG_REASON_WPTANDBKPT:
                        return 0x05; /* SIGTRAP */
                case DBG_REASON_SINGLESTEP:
                        return 0x05; /* SIGTRAP */
                case DBG_REASON_NOTHALTED:
                        return 0x0; /* no signal... shouldn't happen */
                default:
                        LOG_USER("undefined debug reason %d - target needs reset", target->debug_reason);
                        return 0x0;
        }
}

int check_pending(connection_t *connection, int timeout_s, int *got_data)
{
        /* a non-blocking socket will block if there is 0 bytes available on the socket,
         * but return with as many bytes as are available immediately
         */
        struct timeval tv;
        fd_set read_fds;
        gdb_connection_t *gdb_con = connection->priv;
        int t;
        if (got_data==NULL)
                got_data=&t;
        *got_data=0;

        if (gdb_con->buf_cnt>0)
        {
                *got_data = 1;
                return ERROR_OK;
        }

        FD_ZERO(&read_fds);
        FD_SET(connection->fd, &read_fds);

        tv.tv_sec = timeout_s;
        tv.tv_usec = 0;
        if (socket_select(connection->fd + 1, &read_fds, NULL, NULL, &tv) == 0)
        {
                /* This can typically be because a "monitor" command took too long
                 * before printing any progress messages
                 */
                if (timeout_s>0)
                {
                        return ERROR_GDB_TIMEOUT;
                } else
                {
                        return ERROR_OK;
                }
        }
        *got_data=FD_ISSET(connection->fd, &read_fds)!=0;
        return ERROR_OK;
}

int gdb_get_char(connection_t *connection, int* next_char)
{
        gdb_connection_t *gdb_con = connection->priv;
        int retval=ERROR_OK;

#ifdef _DEBUG_GDB_IO_
        char *debug_buffer;
#endif

        if (gdb_con->buf_cnt-- > 0)
        {
                *next_char = *(gdb_con->buf_p++);
                if (gdb_con->buf_cnt > 0)
                        connection->input_pending = 1;
                else
                        connection->input_pending = 0;

#ifdef _DEBUG_GDB_IO_
                LOG_DEBUG("returned char '%c' (0x%2.2x)", *next_char, *next_char);
#endif

                return ERROR_OK;
        }

        for (;;)
        {
                if (connection->service->type == CONNECTION_PIPE)
                {
                        gdb_con->buf_cnt = read(connection->fd, gdb_con->buffer, GDB_BUFFER_SIZE);
                }
                else
                {
                        retval = check_pending(connection, 1, NULL);
                        if (retval != ERROR_OK)
                                return retval;
                        gdb_con->buf_cnt = read_socket(connection->fd, gdb_con->buffer, GDB_BUFFER_SIZE);
                }

                if (gdb_con->buf_cnt > 0)
                {
                        break;
                }
                if (gdb_con->buf_cnt == 0)
                {
                        gdb_con->closed = 1;
                        return ERROR_SERVER_REMOTE_CLOSED;
                }

#ifdef _WIN32
                errno = WSAGetLastError();

                switch(errno)
                {
                        case WSAEWOULDBLOCK:
                                usleep(1000);
                                break;
                        case WSAECONNABORTED:
                                gdb_con->closed = 1;
                                return ERROR_SERVER_REMOTE_CLOSED;
                        case WSAECONNRESET:
                                gdb_con->closed = 1;
                                return ERROR_SERVER_REMOTE_CLOSED;
                        default:
                                LOG_ERROR("read: %d", errno);
                                exit(-1);
                }
#else
                switch(errno)
                {
                        case EAGAIN:
                                usleep(1000);
                                break;
                        case ECONNABORTED:
                                gdb_con->closed = 1;
                                return ERROR_SERVER_REMOTE_CLOSED;
                        case ECONNRESET:
                                gdb_con->closed = 1;
                                return ERROR_SERVER_REMOTE_CLOSED;
                        default:
                                LOG_ERROR("read: %s", strerror(errno));
                                gdb_con->closed = 1;
                                return ERROR_SERVER_REMOTE_CLOSED;
                }
#endif
        }

#ifdef _DEBUG_GDB_IO_
        debug_buffer = malloc(gdb_con->buf_cnt + 1);
        memcpy(debug_buffer, gdb_con->buffer, gdb_con->buf_cnt);
        debug_buffer[gdb_con->buf_cnt] = 0;
        LOG_DEBUG("received '%s'", debug_buffer);
        free(debug_buffer);
#endif

        gdb_con->buf_p = gdb_con->buffer;
        gdb_con->buf_cnt--;
        *next_char = *(gdb_con->buf_p++);
        if (gdb_con->buf_cnt > 0)
                connection->input_pending = 1;
        else
                connection->input_pending = 0;
#ifdef _DEBUG_GDB_IO_
        LOG_DEBUG("returned char '%c' (0x%2.2x)", *next_char, *next_char);
#endif

        return retval;
}

int gdb_putback_char(connection_t *connection, int last_char)
{
        gdb_connection_t *gdb_con = connection->priv;

        if (gdb_con->buf_p > gdb_con->buffer)
        {
                *(--gdb_con->buf_p) = last_char;
                gdb_con->buf_cnt++;
        }
        else
        {
                LOG_ERROR("BUG: couldn't put character back");
        }

        return ERROR_OK;
}

/* The only way we can detect that the socket is closed is the first time
 * we write to it, we will fail. Subsequent write operations will
 * succeed. Shudder! */
int gdb_write(connection_t *connection, void *data, int len)
{
        gdb_connection_t *gdb_con = connection->priv;
        if (gdb_con->closed)
                return ERROR_SERVER_REMOTE_CLOSED;

        if (connection->service->type == CONNECTION_PIPE)
        {
                /* write to stdout */
                if (write(STDOUT_FILENO, data, len) == len)
                {
                        return ERROR_OK;
                }
        }
        else
        {
                if (write_socket(connection->fd, data, len) == len)
                {
                        return ERROR_OK;
                }
        }
        gdb_con->closed = 1;
        return ERROR_SERVER_REMOTE_CLOSED;
}

int gdb_put_packet_inner(connection_t *connection, char *buffer, int len)
{
        int i;
        unsigned char my_checksum = 0;
#ifdef _DEBUG_GDB_IO_
        char *debug_buffer;
#endif
        int reply;
        int retval;
        gdb_connection_t *gdb_con = connection->priv;

        for (i = 0; i < len; i++)
                my_checksum += buffer[i];

#ifdef _DEBUG_GDB_IO_
        /*
         * At this point we should have nothing in the input queue from GDB,
         * however sometimes '-' is sent even though we've already received
         * an ACK (+) for everything we've sent off.
         */
        int gotdata;
        for (;;)
        {
                if ((retval=check_pending(connection, 0, &gotdata))!=ERROR_OK)
                        return retval;
                if (!gotdata)
                        break;
                if ((retval = gdb_get_char(connection, &reply)) != ERROR_OK)
                        return retval;
                if( reply == '$' ){
                        /* fix a problem with some IAR tools */
                        gdb_putback_char( connection, reply );
                        LOG_DEBUG("Unexpected start of new packet");
                        break;
                }

                LOG_WARNING("Discard unexpected char %c", reply);
        }
#endif

        while (1)
        {
#ifdef _DEBUG_GDB_IO_
                debug_buffer = malloc(len + 1);
                memcpy(debug_buffer, buffer, len);
                debug_buffer[len] = 0;
                LOG_DEBUG("sending packet '$%s#%2.2x'", debug_buffer, my_checksum);
                free(debug_buffer);
#endif

                char local_buffer[1024];
                local_buffer[0] = '$';
                if ((size_t)len + 4 <= sizeof(local_buffer))
                {
                        /* performance gain on smaller packets by only a single call to gdb_write() */
                        memcpy(local_buffer+1, buffer, len++);
                        local_buffer[len++] = '#';
                        local_buffer[len++] = DIGITS[(my_checksum >> 4) & 0xf];
                        local_buffer[len++] = DIGITS[my_checksum & 0xf];
                        if((retval = gdb_write(connection, local_buffer, len)) != ERROR_OK)
                        {
                                return retval;
                        }
                }
                else
                {
                        /* larger packets are transmitted directly from caller supplied buffer
                           by several calls to gdb_write() to avoid dynamic allocation */
                        local_buffer[1] = '#';
                        local_buffer[2] = DIGITS[(my_checksum >> 4) & 0xf];
                        local_buffer[3] = DIGITS[my_checksum & 0xf];
                        if((retval = gdb_write(connection, local_buffer, 1)) != ERROR_OK)
                        {
                                return retval;
                        }
                        if((retval = gdb_write(connection, buffer, len)) != ERROR_OK)
                        {
                                return retval;
                        }
                        if((retval = gdb_write(connection, local_buffer+1, 3)) != ERROR_OK)
                        {
                                return retval;
                        }
                }

                if (gdb_con->noack_mode)
                        break;

                if ((retval = gdb_get_char(connection, &reply)) != ERROR_OK)
                        return retval;

                if (reply == '+')
                        break;
                else if (reply == '-')
                {
                        /* Stop sending output packets for now */
                        log_remove_callback(gdb_log_callback, connection);
                        LOG_WARNING("negative reply, retrying");
                }
                else if (reply == 0x3)
                {
                        gdb_con->ctrl_c = 1;
                        if ((retval = gdb_get_char(connection, &reply)) != ERROR_OK)
                                return retval;
                        if (reply == '+')
                                break;
                        else if (reply == '-')
                        {
                                /* Stop sending output packets for now */
                                log_remove_callback(gdb_log_callback, connection);
                                LOG_WARNING("negative reply, retrying");
                        }
                        else if( reply == '$' ){
                                LOG_ERROR("GDB missing ack(1) - assumed good");
                                gdb_putback_char( connection, reply );
                                return ERROR_OK;
                        } else {

                                LOG_ERROR("unknown character(1) 0x%2.2x in reply, dropping connection", reply);
                                gdb_con->closed=1;
                                return ERROR_SERVER_REMOTE_CLOSED;
                        }
                }
                else if( reply == '$' ){
                        LOG_ERROR("GDB missing ack(2) - assumed good");
                        gdb_putback_char( connection, reply );
                        return ERROR_OK;
                }
                else
                {
                        LOG_ERROR("unknown character(2) 0x%2.2x in reply, dropping connection", reply);
                        gdb_con->closed=1;
                        return ERROR_SERVER_REMOTE_CLOSED;
                }
        }
        if (gdb_con->closed)
                return ERROR_SERVER_REMOTE_CLOSED;

        return ERROR_OK;
}

int gdb_put_packet(connection_t *connection, char *buffer, int len)
{
        gdb_connection_t *gdb_con = connection->priv;
        gdb_con->busy = 1;
        int retval = gdb_put_packet_inner(connection, buffer, len);
        gdb_con->busy = 0;

        /* we sent some data, reset timer for keep alive messages */
        kept_alive();

        return retval;
}

static __inline__ int fetch_packet(connection_t *connection, int *checksum_ok, int noack, int *len, char *buffer)
{
        unsigned char my_checksum = 0;
        char checksum[3];
        int character;
        int retval;

        gdb_connection_t *gdb_con = connection->priv;
        my_checksum = 0;
        int count = 0;
        count = 0;
        for (;;)
        {
                /* The common case is that we have an entire packet with no escape chars.
                 * We need to leave at least 2 bytes in the buffer to have
                 * gdb_get_char() update various bits and bobs correctly.
                 */
                if ((gdb_con->buf_cnt > 2) && ((gdb_con->buf_cnt+count) < *len))
                {
                        /* The compiler will struggle a bit with constant propagation and
                         * aliasing, so we help it by showing that these values do not
                         * change inside the loop
                         */
                        int i;
                        char *buf = gdb_con->buf_p;
                        int run = gdb_con->buf_cnt - 2;
                        i = 0;
                        int done = 0;
                        while (i < run)
                        {
                                character = *buf++;
                                i++;
                                if (character == '#')
                                {
                                        /* Danger! character can be '#' when esc is
                                         * used so we need an explicit boolean for done here.
                                         */
                                        done = 1;
                                        break;
                                }

                                if (character == '}')
                                {
                                        /* data transmitted in binary mode (X packet)
                                         * uses 0x7d as escape character */
                                        my_checksum += character & 0xff;
                                        character = *buf++;
                                        i++;
                                        my_checksum += character & 0xff;
                                        buffer[count++] = (character ^ 0x20) & 0xff;
                                }
                                else
                                {
                                        my_checksum += character & 0xff;
                                        buffer[count++] = character & 0xff;
                                }
                        }
                        gdb_con->buf_p += i;
                        gdb_con->buf_cnt -= i;
                        if (done)
                                break;
                }
                if (count > *len)
                {
                        LOG_ERROR("packet buffer too small");
                        return ERROR_GDB_BUFFER_TOO_SMALL;
                }

                if ((retval = gdb_get_char(connection, &character)) != ERROR_OK)
                        return retval;

                if (character == '#')
                        break;

                if (character == '}')
                {
                        /* data transmitted in binary mode (X packet)
                         * uses 0x7d as escape character */
                        my_checksum += character & 0xff;
                        if ((retval = gdb_get_char(connection, &character)) != ERROR_OK)
                                return retval;
                        my_checksum += character & 0xff;
                        buffer[count++] = (character ^ 0x20) & 0xff;
                }
                else
                {
                        my_checksum += character & 0xff;
                        buffer[count++] = character & 0xff;
                }
        }

        *len = count;

        if ((retval = gdb_get_char(connection, &character)) != ERROR_OK)
                return retval;
        checksum[0] = character;
        if ((retval = gdb_get_char(connection, &character)) != ERROR_OK)
                return retval;
        checksum[1] = character;
        checksum[2] = 0;

        if (!noack)
        {
                *checksum_ok=(my_checksum == strtoul(checksum, NULL, 16));
        }

        return ERROR_OK;
}

int gdb_get_packet_inner(connection_t *connection, char *buffer, int *len)
{
        int character;
        int retval;
        gdb_connection_t *gdb_con = connection->priv;

        while (1)
        {
                do
                {
                        if ((retval = gdb_get_char(connection, &character)) != ERROR_OK)
                                return retval;

#ifdef _DEBUG_GDB_IO_
                        LOG_DEBUG("character: '%c'", character);
#endif

                        switch (character)
                        {
                                case '$':
                                        break;
                                case '+':
                                        /* gdb sends a dummy ack '+' at every remote connect - see remote_start_remote (remote.c)
                                         * incase anyone tries to debug why they receive this warning every time */
                                        LOG_WARNING("acknowledgment received, but no packet pending");
                                        break;
                                case '-':
                                        LOG_WARNING("negative acknowledgment, but no packet pending");
                                        break;
                                case 0x3:
                                        gdb_con->ctrl_c = 1;
                                        *len = 0;
                                        return ERROR_OK;
                                default:
                                        LOG_WARNING("ignoring character 0x%x", character);
                                        break;
                        }
                } while (character != '$');



                int checksum_ok = 0;
                /* explicit code expansion here to get faster inlined code in -O3 by not
                 * calculating checksum
                 */
                if (gdb_con->noack_mode)
                {
                        if ((retval=fetch_packet(connection, &checksum_ok, 1, len, buffer))!=ERROR_OK)
                                return retval;
                } else
                {
                        if ((retval=fetch_packet(connection, &checksum_ok, 0, len, buffer))!=ERROR_OK)
                                return retval;
                }

                if (gdb_con->noack_mode)
                {
                        /* checksum is not checked in noack mode */
                        break;
                }
                if (checksum_ok)
                {
                        if ((retval = gdb_write(connection, "+", 1)) != ERROR_OK)
                        {
                                return retval;
                        }
                        break;
                }
        }
        if (gdb_con->closed)
                return ERROR_SERVER_REMOTE_CLOSED;

        return ERROR_OK;
}

int gdb_get_packet(connection_t *connection, char *buffer, int *len)
{
        gdb_connection_t *gdb_con = connection->priv;
        gdb_con->busy = 1;
        int retval = gdb_get_packet_inner(connection, buffer, len);
        gdb_con->busy = 0;
        return retval;
}

int gdb_output_con(connection_t *connection, const char* line)
{
        char *hex_buffer;
        int i, bin_size;

        bin_size = strlen(line);

        hex_buffer = malloc(bin_size*2 + 2);
        if (hex_buffer == NULL)
                return ERROR_GDB_BUFFER_TOO_SMALL;

        hex_buffer[0] = 'O';
        for (i=0; i<bin_size; i++)
                snprintf(hex_buffer + 1 + i*2, 3, "%2.2x", line[i]);
        hex_buffer[bin_size*2+1] = 0;

        int retval = gdb_put_packet(connection, hex_buffer, bin_size*2 + 1);

        free(hex_buffer);
        return retval;
}

int gdb_output(struct command_context_s *context, const char* line)
{
        /* this will be dumped to the log and also sent as an O packet if possible */
        LOG_USER_N("%s", line);
        return ERROR_OK;
}


static void gdb_frontend_halted(struct target_s *target, connection_t *connection)
{
        gdb_connection_t *gdb_connection = connection->priv;

        /* In the GDB protocol when we are stepping or coninuing execution,
         * we have a lingering reply. Upon receiving a halted event
         * when we have that lingering packet, we reply to the original
         * step or continue packet.
         *
         * Executing monitor commands can bring the target in and
         * out of the running state so we'll see lots of TARGET_EVENT_XXX
         * that are to be ignored.
         */
        if (gdb_connection->frontend_state == TARGET_RUNNING)
        {
                char sig_reply[4];
                int signal;

                /* stop forwarding log packets! */
                log_remove_callback(gdb_log_callback, connection);

                if (gdb_connection->ctrl_c)
                {
                        signal = 0x2;
                        gdb_connection->ctrl_c = 0;
                }
                else
                {
                        signal = gdb_last_signal(target);
                }

                snprintf(sig_reply, 4, "T%2.2x", signal);
                gdb_put_packet(connection, sig_reply, 3);
                gdb_connection->frontend_state = TARGET_HALTED;
        }
}

int gdb_target_callback_event_handler(struct target_s *target, enum target_event event, void *priv)
{
        int retval;
        connection_t *connection = priv;

        target_handle_event( target, event );
        switch (event)
        {
                case TARGET_EVENT_EARLY_HALTED:
                        gdb_frontend_halted(target, connection);
                        break;
                case TARGET_EVENT_HALTED:
                        target_call_event_callbacks(target, TARGET_EVENT_GDB_END);
                        break;
                case TARGET_EVENT_GDB_FLASH_ERASE_START:
                        target_handle_event( target, TARGET_EVENT_OLD_gdb_program_config );
                        if((retval = jtag_execute_queue()) != ERROR_OK)
                        {
                                return retval;
                        }
                        break;
                default:
                        break;
        }

        return ERROR_OK;
}

int gdb_new_connection(connection_t *connection)
{
        gdb_connection_t *gdb_connection = malloc(sizeof(gdb_connection_t));
        gdb_service_t *gdb_service = connection->service->priv;
        int retval;
        int initial_ack;

        connection->priv = gdb_connection;

        /* initialize gdb connection information */
        gdb_connection->buf_p = gdb_connection->buffer;
        gdb_connection->buf_cnt = 0;
        gdb_connection->ctrl_c = 0;
        gdb_connection->frontend_state = TARGET_HALTED;
        gdb_connection->vflash_image = NULL;
        gdb_connection->closed = 0;
        gdb_connection->busy = 0;
        gdb_connection->noack_mode = 0;

        /* send ACK to GDB for debug request */
        gdb_write(connection, "+", 1);

        /* output goes through gdb connection */
        command_set_output_handler(connection->cmd_ctx, gdb_output, connection);

        /* we must remove all breakpoints registered to the target as a previous
         * GDB session could leave dangling breakpoints if e.g. communication
         * timed out.
         */
        breakpoint_clear_target(gdb_service->target);
        watchpoint_clear_target(gdb_service->target);

        /* register callback to be informed about target events */
        target_register_event_callback(gdb_target_callback_event_handler, connection);

        /* a gdb session just attached, try to put the target in halt mode.
         *
         * DANGER!!!!
         *
         * If the halt fails(e.g. target needs a reset, JTAG communication not
         * working, etc.), then the GDB connect will succeed as
         * the get_gdb_reg_list() will lie and return a register list with
         * dummy values.
         *
         * This allows GDB monitor commands to be run from a GDB init script to
         * initialize the target
         *
         * Also, since the halt() is asynchronous target connect will be
         * instantaneous and thus avoiding annoying timeout problems during
         * connect.
         */
        target_halt(gdb_service->target);
        /* FIX!!!! could extended-remote work better here?
         *
         *  wait a tiny bit for halted state or we just continue. The
         * GDB register packet will then contain garbage
         */
        target_wait_state(gdb_service->target, TARGET_HALTED, 500);

        /* remove the initial ACK from the incoming buffer */
        if ((retval = gdb_get_char(connection, &initial_ack)) != ERROR_OK)
                return retval;

        /* FIX!!!??? would we actually ever receive a + here???
         * Not observed.
         */
        if (initial_ack != '+')
                gdb_putback_char(connection, initial_ack);
        target_call_event_callbacks(gdb_service->target, TARGET_EVENT_GDB_ATTACH );
        return ERROR_OK;
}

int gdb_connection_closed(connection_t *connection)
{
        gdb_service_t *gdb_service = connection->service->priv;
        gdb_connection_t *gdb_connection = connection->priv;

        /* see if an image built with vFlash commands is left */
        if (gdb_connection->vflash_image)
        {
                image_close(gdb_connection->vflash_image);
                free(gdb_connection->vflash_image);
                gdb_connection->vflash_image = NULL;
        }

        /* if this connection registered a debug-message receiver delete it */
        delete_debug_msg_receiver(connection->cmd_ctx, gdb_service->target);

        if (connection->priv)
        {
                free(connection->priv);
                connection->priv = NULL;
        }
        else
        {
                LOG_ERROR("BUG: connection->priv == NULL");
        }

        target_unregister_event_callback(gdb_target_callback_event_handler, connection);
        target_call_event_callbacks(gdb_service->target, TARGET_EVENT_GDB_END);
        log_remove_callback(gdb_log_callback, connection);

        target_call_event_callbacks(gdb_service->target, TARGET_EVENT_GDB_DETACH );

        return ERROR_OK;
}

void gdb_send_error(connection_t *connection, u8 the_error)
{
        char err[4];
        snprintf(err, 4, "E%2.2X", the_error );
        gdb_put_packet(connection, err, 3);
}

int gdb_last_signal_packet(connection_t *connection, target_t *target, char* packet, int packet_size)
{
        char sig_reply[4];
        int signal;

        signal = gdb_last_signal(target);

        snprintf(sig_reply, 4, "S%2.2x", signal);
        gdb_put_packet(connection, sig_reply, 3);

        return ERROR_OK;
}

static int gdb_reg_pos(target_t *target, int pos, int len)
{
        if (target->endianness == TARGET_LITTLE_ENDIAN)
                return pos;
        else
                return len - 1 - pos;
}

/* Convert register to string of bytes. NB! The # of bits in the
 * register might be non-divisible by 8(a byte), in which
 * case an entire byte is shown.
 *
 * NB! the format on the wire is the target endianess
 *
 * The format of reg->value is little endian
 *
 */
void gdb_str_to_target(target_t *target, char *tstr, reg_t *reg)
{
        int i;

        u8 *buf;
        int buf_len;
        buf = reg->value;
        buf_len = CEIL(reg->size, 8);

        for (i = 0; i < buf_len; i++)
        {
                int j = gdb_reg_pos(target, i, buf_len);
                tstr[i*2]   = DIGITS[(buf[j]>>4) & 0xf];
                tstr[i*2+1] = DIGITS[buf[j]&0xf];
        }
}

static int hextoint(char c)
{
        if (c>='0'&&c<='9')
        {
                return c-'0';
        }
        c=toupper(c);
        if (c>='A'&&c<='F')
        {
                return c-'A'+10;
        }
        LOG_ERROR("BUG: invalid register value %08x", c);
        return 0;
}

/* copy over in register buffer */
void gdb_target_to_reg(target_t *target, char *tstr, int str_len, u8 *bin)
{
        if (str_len % 2)
        {
                LOG_ERROR("BUG: gdb value with uneven number of characters encountered");
                exit(-1);
        }

        int i;
        for (i = 0; i < str_len; i+=2)
        {
                u8 t = hextoint(tstr[i])<<4;
                t |= hextoint(tstr[i+1]);

                int j = gdb_reg_pos(target, i/2, str_len/2);
                bin[j] = t;
        }
}

int gdb_get_registers_packet(connection_t *connection, target_t *target, char* packet, int packet_size)
{
        reg_t **reg_list;
        int reg_list_size;
        int retval;
        int reg_packet_size = 0;
        char *reg_packet;
        char *reg_packet_p;
        int i;

#ifdef _DEBUG_GDB_IO_
        LOG_DEBUG("-");
#endif

        if ((retval = target->type->get_gdb_reg_list(target, &reg_list, &reg_list_size)) != ERROR_OK)
        {
                return gdb_error(connection, retval);
        }

        for (i = 0; i < reg_list_size; i++)
        {
                reg_packet_size += reg_list[i]->size;
        }

        reg_packet = malloc(CEIL(reg_packet_size, 8) * 2);
        reg_packet_p = reg_packet;

        for (i = 0; i < reg_list_size; i++)
        {
                gdb_str_to_target(target, reg_packet_p, reg_list[i]);
                reg_packet_p += CEIL(reg_list[i]->size, 8) * 2;
        }

#ifdef _DEBUG_GDB_IO_
        {
                char *reg_packet_p;
                reg_packet_p = strndup(reg_packet, CEIL(reg_packet_size, 8) * 2);
                LOG_DEBUG("reg_packet: %s", reg_packet_p);
                free(reg_packet_p);
        }
#endif

        gdb_put_packet(connection, reg_packet, CEIL(reg_packet_size, 8) * 2);
        free(reg_packet);

        free(reg_list);

        return ERROR_OK;
}

int gdb_set_registers_packet(connection_t *connection, target_t *target, char *packet, int packet_size)
{
        int i;
        reg_t **reg_list;
        int reg_list_size;
        int retval;
        char *packet_p;

#ifdef _DEBUG_GDB_IO_
        LOG_DEBUG("-");
#endif

        /* skip command character */
        packet++;
        packet_size--;

        if (packet_size % 2)
        {
                LOG_WARNING("GDB set_registers packet with uneven characters received, dropping connection");
                return ERROR_SERVER_REMOTE_CLOSED;
        }

        if ((retval = target->type->get_gdb_reg_list(target, &reg_list, &reg_list_size)) != ERROR_OK)
        {
                return gdb_error(connection, retval);
        }

        packet_p = packet;
        for (i = 0; i < reg_list_size; i++)
        {
                u8 *bin_buf;
                int chars = (CEIL(reg_list[i]->size, 8) * 2);

                if (packet_p + chars > packet + packet_size)
                {
                        LOG_ERROR("BUG: register packet is too small for registers");
                }

                reg_arch_type_t *arch_type;
                bin_buf = malloc(CEIL(reg_list[i]->size, 8));
                gdb_target_to_reg(target, packet_p, chars, bin_buf);

                /* get register arch_type, and call set method */
                arch_type = register_get_arch_type(reg_list[i]->arch_type);

                arch_type->set(reg_list[i], bin_buf);

                /* advance packet pointer */
                packet_p += chars;


                free(bin_buf);
        }

        /* free reg_t *reg_list[] array allocated by get_gdb_reg_list */
        free(reg_list);

        gdb_put_packet(connection, "OK", 2);

        return ERROR_OK;
}

int gdb_get_register_packet(connection_t *connection, target_t *target, char *packet, int packet_size)
{
        char *reg_packet;
        int reg_num = strtoul(packet + 1, NULL, 16);
        reg_t **reg_list;
        int reg_list_size;
        int retval;

#ifdef _DEBUG_GDB_IO_
        LOG_DEBUG("-");
#endif

        if ((retval = target->type->get_gdb_reg_list(target, &reg_list, &reg_list_size)) != ERROR_OK)
        {
                return gdb_error(connection, retval);
        }

        if (reg_list_size <= reg_num)
        {
                LOG_ERROR("gdb requested a non-existing register");
                exit(-1);
        }

        reg_packet = malloc(CEIL(reg_list[reg_num]->size, 8) * 2);

        gdb_str_to_target(target, reg_packet, reg_list[reg_num]);

        gdb_put_packet(connection, reg_packet, CEIL(reg_list[reg_num]->size, 8) * 2);

        free(reg_list);
        free(reg_packet);

        return ERROR_OK;
}

int gdb_set_register_packet(connection_t *connection, target_t *target, char *packet, int packet_size)
{
        char *separator;
        u8 *bin_buf;
        int reg_num = strtoul(packet + 1, &separator, 16);
        reg_t **reg_list;
        int reg_list_size;
        int retval;
        reg_arch_type_t *arch_type;

        LOG_DEBUG("-");

        if ((retval = target->type->get_gdb_reg_list(target, &reg_list, &reg_list_size)) != ERROR_OK)
        {
                return gdb_error(connection, retval);
        }

        if (reg_list_size < reg_num)
        {
                LOG_ERROR("gdb requested a non-existing register");
                return ERROR_SERVER_REMOTE_CLOSED;
        }

        if (*separator != '=')
        {
                LOG_ERROR("GDB 'set register packet', but no '=' following the register number");
                return ERROR_SERVER_REMOTE_CLOSED;
        }

        /* convert from GDB-string (target-endian) to hex-string (big-endian) */
        bin_buf = malloc(CEIL(reg_list[reg_num]->size, 8));
        int chars = (CEIL(reg_list[reg_num]->size, 8) * 2);

        /* fix!!! add some sanity checks on packet size here */

        gdb_target_to_reg(target, separator + 1, chars, bin_buf);

                /* get register arch_type, and call set method */
        arch_type = register_get_arch_type(reg_list[reg_num]->arch_type);
        arch_type->set(reg_list[reg_num], bin_buf);

        gdb_put_packet(connection, "OK", 2);

        free(bin_buf);
        free(reg_list);

        return ERROR_OK;
}

int gdb_error(connection_t *connection, int retval)
{
        switch (retval)
        {
                case ERROR_TARGET_DATA_ABORT:
                        gdb_send_error(connection, EIO);
                        break;
                case ERROR_TARGET_TRANSLATION_FAULT:
                        gdb_send_error(connection, EFAULT);
                        break;
                case ERROR_TARGET_UNALIGNED_ACCESS:
                        gdb_send_error(connection, EFAULT);
                        break;
                case ERROR_TARGET_NOT_HALTED:
                        gdb_send_error(connection, EFAULT);
                        break;
                default:
                        /* This could be that the target reset itself. */
                        LOG_ERROR("unexpected error %i", retval);
                        gdb_send_error(connection, EFAULT);
                        break;
        }

        return ERROR_OK;
}

/* We don't have to worry about the default 2 second timeout for GDB packets,
 * because GDB breaks up large memory reads into smaller reads.
 *
 * 8191 bytes by the looks of it. Why 8191 bytes instead of 8192?????
 */
int gdb_read_memory_packet(connection_t *connection, target_t *target, char *packet, int packet_size)
{
        char *separator;
        u32 addr = 0;
        u32 len = 0;

        u8 *buffer;
        char *hex_buffer;

        int retval = ERROR_OK;

        /* skip command character */
        packet++;

        addr = strtoul(packet, &separator, 16);

        if (*separator != ',')
        {
                LOG_ERROR("incomplete read memory packet received, dropping connection");
                return ERROR_SERVER_REMOTE_CLOSED;
        }

        len = strtoul(separator+1, NULL, 16);

        buffer = malloc(len);

        LOG_DEBUG("addr: 0x%8.8x, len: 0x%8.8x", addr, len);

        retval = target_read_buffer(target, addr, len, buffer);

        if ((retval!=ERROR_OK)&&!gdb_report_data_abort)
        {
                /* TODO : Here we have to lie and send back all zero's lest stack traces won't work.
                 * At some point this might be fixed in GDB, in which case this code can be removed.
                 *
                 * OpenOCD developers are acutely aware of this problem, but there is nothing
                 * gained by involving the user in this problem that hopefully will get resolved
                 * eventually
                 *
                 * http://sourceware.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gdb&pr=2395
                 *
                 * For now, the default is to fix up things to make current GDB versions work.
                 * This can be overwritten using the gdb_report_data_abort <'enable'|'disable'> command.
                 */
                memset(buffer, 0, len);
                retval = ERROR_OK;
        }

        if (retval == ERROR_OK)
        {
                hex_buffer = malloc(len * 2 + 1);

                u32 i;
                for (i = 0; i < len; i++)
                {
                        u8 t = buffer[i];
                        hex_buffer[2 * i] = DIGITS[(t >> 4) & 0xf];
                        hex_buffer[2 * i + 1] = DIGITS[t & 0xf];
                }

                gdb_put_packet(connection, hex_buffer, len * 2);

                free(hex_buffer);
        }
        else
        {
                retval = gdb_error(connection, retval);
        }

        free(buffer);

        return retval;
}

int gdb_write_memory_packet(connection_t *connection, target_t *target, char *packet, int packet_size)
{
        char *separator;
        u32 addr = 0;
        u32 len = 0;

        u8 *buffer;

        u32 i;
        int retval;

        /* skip command character */
        packet++;

        addr = strtoul(packet, &separator, 16);

        if (*separator != ',')
        {
                LOG_ERROR("incomplete write memory packet received, dropping connection");
                return ERROR_SERVER_REMOTE_CLOSED;
        }

        len = strtoul(separator+1, &separator, 16);

        if (*(separator++) != ':')
        {
                LOG_ERROR("incomplete write memory packet received, dropping connection");
                return ERROR_SERVER_REMOTE_CLOSED;
        }

        buffer = malloc(len);

        LOG_DEBUG("addr: 0x%8.8x, len: 0x%8.8x", addr, len);

        for (i=0; i<len; i++)
        {
                u32 tmp;
                sscanf(separator + 2*i, "%2x", &tmp);
                buffer[i] = tmp;
        }

        retval = target_write_buffer(target, addr, len, buffer);

        if (retval == ERROR_OK)
        {
                gdb_put_packet(connection, "OK", 2);
        }
        else
        {
                retval = gdb_error(connection, retval);
        }

        free(buffer);

        return retval;
}

int gdb_write_memory_binary_packet(connection_t *connection, target_t *target, char *packet, int packet_size)
{
        char *separator;
        u32 addr = 0;
        u32 len = 0;

        int retval;

        /* skip command character */
        packet++;

        addr = strtoul(packet, &separator, 16);

        if (*separator != ',')
        {
                LOG_ERROR("incomplete write memory binary packet received, dropping connection");
                return ERROR_SERVER_REMOTE_CLOSED;
        }

        len = strtoul(separator+1, &separator, 16);

        if (*(separator++) != ':')
        {
                LOG_ERROR("incomplete write memory binary packet received, dropping connection");
                return ERROR_SERVER_REMOTE_CLOSED;
        }

        retval = ERROR_OK;
        if (len)
        {
                LOG_DEBUG("addr: 0x%8.8x, len: 0x%8.8x", addr, len);

                retval = target_write_buffer(target, addr, len, (u8*)separator);
        }

        if (retval == ERROR_OK)
        {
                gdb_put_packet(connection, "OK", 2);
        }
        else
        {
                if ((retval = gdb_error(connection, retval)) != ERROR_OK)
                        return retval;
        }

        return ERROR_OK;
}

int gdb_step_continue_packet(connection_t *connection, target_t *target, char *packet, int packet_size)
{
        int current = 0;
        u32 address = 0x0;
        int retval=ERROR_OK;

        LOG_DEBUG("-");

        if (packet_size > 1)
        {
                packet[packet_size] = 0;
                address = strtoul(packet + 1, NULL, 16);
        }
        else
        {
                current = 1;
        }

        if (packet[0] == 'c')
        {
                LOG_DEBUG("continue");
                target_handle_event( target, TARGET_EVENT_OLD_pre_resume );
                retval=target_resume(target, current, address, 0, 0); /* resume at current address, don't handle breakpoints, not debugging */
        }
        else if (packet[0] == 's')
        {
                LOG_DEBUG("step");
                retval=target->type->step(target, current, address, 0); /* step at current or address, don't handle breakpoints */
        }
        return retval;
}

int gdb_breakpoint_watchpoint_packet(connection_t *connection, target_t *target, char *packet, int packet_size)
{
        int type;
        enum breakpoint_type bp_type = BKPT_SOFT /* dummy init to avoid warning */;
        enum watchpoint_rw wp_type;
        u32 address;
        u32 size;
        char *separator;
        int retval;

        LOG_DEBUG("-");

        type = strtoul(packet + 1, &separator, 16);

        if (type == 0)  /* memory breakpoint */
                bp_type = BKPT_SOFT;
        else if (type == 1) /* hardware breakpoint */
                bp_type = BKPT_HARD;
        else if (type == 2) /* write watchpoint */
                wp_type = WPT_WRITE;
        else if (type == 3) /* read watchpoint */
                wp_type = WPT_READ;
        else if (type == 4) /* access watchpoint */
                wp_type = WPT_ACCESS;

        if (gdb_breakpoint_override&&((bp_type==BKPT_SOFT)||(bp_type==BKPT_HARD)))
        {
                bp_type=gdb_breakpoint_override_type;
        }

        if (*separator != ',')
        {
                LOG_ERROR("incomplete breakpoint/watchpoint packet received, dropping connection");
                return ERROR_SERVER_REMOTE_CLOSED;
        }

        address = strtoul(separator+1, &separator, 16);

        if (*separator != ',')
        {
                LOG_ERROR("incomplete breakpoint/watchpoint packet received, dropping connection");
                return ERROR_SERVER_REMOTE_CLOSED;
        }

        size = strtoul(separator+1, &separator, 16);

        switch (type)
        {
                case 0:
                case 1:
                        if (packet[0] == 'Z')
                        {
                                if ((retval = breakpoint_add(target, address, size, bp_type)) != ERROR_OK)
                                {
                                        if ((retval = gdb_error(connection, retval)) != ERROR_OK)
                                                return retval;
                                }
                                else
                                {
                                        gdb_put_packet(connection, "OK", 2);
                                }
                        }
                        else
                        {
                                breakpoint_remove(target, address);
                                gdb_put_packet(connection, "OK", 2);
                        }
                        break;
                case 2:
                case 3:
                case 4:
                {
                        if (packet[0] == 'Z')
                        {
                                if ((retval = watchpoint_add(target, address, size, type-2, 0, 0xffffffffu)) != ERROR_OK)
                                {
                                        if ((retval = gdb_error(connection, retval)) != ERROR_OK)
                                                return retval;
                                }
                                else
                                {
                                        gdb_put_packet(connection, "OK", 2);
                                }
                        }
                        else
                        {
                                watchpoint_remove(target, address);
                                gdb_put_packet(connection, "OK", 2);
                        }
                        break;
                }
                default:
                        break;
        }

        return ERROR_OK;
}

/* print out a string and allocate more space as needed, mainly used for XML at this point */
void xml_printf(int *retval, char **xml, int *pos, int *size, const char *fmt, ...)
{
        if (*retval != ERROR_OK)
        {
                return;
        }
        int first = 1;

        for (;;)
        {
                if ((*xml == NULL) || (!first))
                {
                        /* start by 0 to exercise all the code paths.
                         * Need minimum 2 bytes to fit 1 char and 0 terminator. */

                        *size = *size * 2 + 2;
                        char *t = *xml;
                        *xml = realloc(*xml, *size);
                        if (*xml == NULL)
                        {
                                if (t)
                                        free(t);
                                *retval = ERROR_SERVER_REMOTE_CLOSED;
                                return;
                        }
                }

                va_list ap;
                int ret;
                va_start(ap, fmt);
                ret = vsnprintf(*xml + *pos, *size - *pos, fmt, ap);
                va_end(ap);
                if ((ret > 0) && ((ret + 1) < *size - *pos))
                {
                        *pos += ret;
                        return;
                }
                /* there was just enough or not enough space, allocate more. */
                first = 0;
        }
}

static int decode_xfer_read(char *buf, char **annex, int *ofs, unsigned int *len)
{
        char *separator;

        /* Extract and NUL-terminate the annex. */
        *annex = buf;
        while (*buf && *buf != ':')
                buf++;
        if (*buf == '\0')
                return -1;
        *buf++ = 0;

        /* After the read marker and annex, qXfer looks like a
         * traditional 'm' packet. */

        *ofs = strtoul(buf, &separator, 16);

        if (*separator != ',')
                return -1;

        *len = strtoul(separator+1, NULL, 16);

        return 0;
}

int gdb_calc_blocksize(flash_bank_t *bank)
{
        u32 i;
        u32 block_size = 0xffffffff;

        /* loop through all sectors and return smallest sector size */

        for (i = 0; i < (u32)bank->num_sectors; i++)
        {
                if (bank->sectors[i].size < block_size)
                        block_size = bank->sectors[i].size;
        }

        return block_size;
}

static int compare_bank (const void * a, const void * b)
{
        flash_bank_t *b1, *b2;
        b1=*((flash_bank_t **)a);
        b2=*((flash_bank_t **)b);

        if (b1->base==b2->base)
        {
                return 0;
        } else if (b1->base>b2->base)
        {
                return 1;
        } else
        {
                return -1;
        }
}

int gdb_query_packet(connection_t *connection, target_t *target, char *packet, int packet_size)
{
        command_context_t *cmd_ctx = connection->cmd_ctx;
        gdb_connection_t *gdb_connection = connection->priv;

        if (strstr(packet, "qRcmd,"))
        {
                if (packet_size > 6)
                {
                        char *cmd;
                        int i;
                        cmd = malloc((packet_size - 6)/2 + 1);
                        for (i=0; i < (packet_size - 6)/2; i++)
                        {
                                u32 tmp;
                                sscanf(packet + 6 + 2*i, "%2x", &tmp);
                                cmd[i] = tmp;
                        }
                        cmd[(packet_size - 6)/2] = 0x0;

                        /* We want to print all debug output to GDB connection */
                        log_add_callback(gdb_log_callback, connection);
                        target_call_timer_callbacks_now();
                        command_run_line(cmd_ctx, cmd);
                        target_call_timer_callbacks_now();
                        log_remove_callback(gdb_log_callback, connection);
                        free(cmd);
                }
                gdb_put_packet(connection, "OK", 2);
                return ERROR_OK;
        }
        else if (strstr(packet, "qCRC:"))
        {
                if (packet_size > 5)
                {
                        int retval;
                        char gdb_reply[10];
                        char *separator;
                        u32 checksum;
                        u32 addr = 0;
                        u32 len = 0;

                        /* skip command character */
                        packet += 5;

                        addr = strtoul(packet, &separator, 16);

                        if (*separator != ',')
                        {
                                LOG_ERROR("incomplete read memory packet received, dropping connection");
                                return ERROR_SERVER_REMOTE_CLOSED;
                        }

                        len = strtoul(separator + 1, NULL, 16);

                        retval = target_checksum_memory(target, addr, len, &checksum);

                        if (retval == ERROR_OK)
                        {
                                snprintf(gdb_reply, 10, "C%8.8x", checksum);
                                gdb_put_packet(connection, gdb_reply, 9);
                        }
                        else
                        {
                                if ((retval = gdb_error(connection, retval)) != ERROR_OK)
                                        return retval;
                        }

                        return ERROR_OK;
                }
        }
        else if (strstr(packet, "qSupported"))
        {
                /* we currently support packet size and qXfer:memory-map:read (if enabled)
                 * disable qXfer:features:read for the moment */
                int retval = ERROR_OK;
                char *buffer = NULL;
                int pos = 0;
                int size = 0;

                xml_printf(&retval, &buffer, &pos, &size,
                                "PacketSize=%x;qXfer:memory-map:read%c;qXfer:features:read-;QStartNoAckMode+",
                                (GDB_BUFFER_SIZE - 1), ((gdb_use_memory_map == 1)&&(flash_get_bank_count()>0)) ? '+' : '-');

                if (retval != ERROR_OK)
                {
                        gdb_send_error(connection, 01);
                        return ERROR_OK;
                }

                gdb_put_packet(connection, buffer, strlen(buffer));
                free(buffer);

                return ERROR_OK;
        }
        else if (strstr(packet, "qXfer:memory-map:read::")&&(flash_get_bank_count()>0))
        {
                /* We get away with only specifying flash here. Regions that are not
                 * specified are treated as if we provided no memory map(if not we
                 * could detect the holes and mark them as RAM).
                 * Normally we only execute this code once, but no big deal if we
                 * have to regenerate it a couple of times. */

                flash_bank_t *p;
                char *xml = NULL;
                int size = 0;
                int pos = 0;
                int retval = ERROR_OK;

                int offset;
                int length;
                char *separator;
                int blocksize;

                /* skip command character */
                packet += 23;

                offset = strtoul(packet, &separator, 16);
                length = strtoul(separator + 1, &separator, 16);

                xml_printf(&retval, &xml, &pos, &size, "<memory-map>\n");

                /*
                sort banks in ascending order, we need to make non-flash memory be ram(or rather
                read/write) by default for GDB.
                GDB does not have a concept of non-cacheable read/write memory.
                 */
                flash_bank_t **banks=malloc(sizeof(flash_bank_t *)*flash_get_bank_count());
                int i;

                for (i=0; i<flash_get_bank_count(); i++)
                {
                        p = get_flash_bank_by_num(i);
                        if (p == NULL)
                        {
                                free(banks);
                                retval = ERROR_FAIL;
                                gdb_send_error(connection, retval);
                                return retval;
                        }
                        banks[i]=p;
                }

                qsort(banks, flash_get_bank_count(), sizeof(flash_bank_t *), compare_bank);

                u32 ram_start=0;
                for (i=0; i<flash_get_bank_count(); i++)
                {
                        p = banks[i];

                        if (ram_start<p->base)
                        {
                                xml_printf(&retval, &xml, &pos, &size, "<memory type=\"ram\" start=\"0x%x\" length=\"0x%x\"/>\n",
                                        ram_start, p->base-ram_start);
                        }

                        /* if device has uneven sector sizes, eg. str7, lpc
                         * we pass the smallest sector size to gdb memory map */
                        blocksize = gdb_calc_blocksize(p);

                        xml_printf(&retval, &xml, &pos, &size, "<memory type=\"flash\" start=\"0x%x\" length=\"0x%x\">\n" \
                                "<property name=\"blocksize\">0x%x</property>\n" \
                                "</memory>\n", \
                                p->base, p->size, blocksize);
                        ram_start=p->base+p->size;
                }
                if (ram_start!=0)
                {
                        xml_printf(&retval, &xml, &pos, &size, "<memory type=\"ram\" start=\"0x%x\" length=\"0x%x\"/>\n",
                                ram_start, 0-ram_start);
                } else
                {
                        /* a flash chip could be at the very end of the 32 bit address space, in which case
                        ram_start will be precisely 0 */
                }

                free(banks);
                banks = NULL;

                xml_printf(&retval, &xml, &pos, &size, "</memory-map>\n");

                if (retval != ERROR_OK)
                {
                        gdb_send_error(connection, retval);
                        return retval;
                }

                if (offset + length > pos)
                {
                        length = pos - offset;
                }

                char *t = malloc(length + 1);
                t[0] = 'l';
                memcpy(t + 1, xml + offset, length);
                gdb_put_packet(connection, t, length + 1);

                free(t);
                free(xml);
                return ERROR_OK;
        }
        else if (strstr(packet, "qXfer:features:read:"))
        {
                char *xml = NULL;
                int size = 0;
                int pos = 0;
                int retval = ERROR_OK;

                int offset;
                unsigned int length;
                char *annex;

                /* skip command character */
                packet += 20;

                if (decode_xfer_read(packet, &annex, &offset, &length) < 0)
                {
                        gdb_send_error(connection, 01);
                        return ERROR_OK;
                }

                if (strcmp(annex, "target.xml") != 0)
                {
                        gdb_send_error(connection, 01);
                        return ERROR_OK;
                }

                xml_printf(&retval, &xml, &pos, &size, \
                        "l<target version=\"1.0\">\n<architecture>arm</architecture>\n</target>\n");

                if (retval != ERROR_OK)
                {
                        gdb_send_error(connection, retval);
                        return retval;
                }

                gdb_put_packet(connection, xml, strlen(xml));

                free(xml);
                return ERROR_OK;
        }
        else if (strstr(packet, "QStartNoAckMode"))
        {
                gdb_connection->noack_mode = 1;
                gdb_put_packet(connection, "OK", 2);
                return ERROR_OK;
        }

        gdb_put_packet(connection, "", 0);
        return ERROR_OK;
}

int gdb_v_packet(connection_t *connection, target_t *target, char *packet, int packet_size)
{
        gdb_connection_t *gdb_connection = connection->priv;
        gdb_service_t *gdb_service = connection->service->priv;
        int result;

        /* if flash programming disabled - send a empty reply */

        if (gdb_flash_program == 0)
        {
                gdb_put_packet(connection, "", 0);
                return ERROR_OK;
        }

        if (strstr(packet, "vFlashErase:"))
        {
                unsigned long addr;
                unsigned long length;

                char *parse = packet + 12;
                if (*parse == '\0')
                {
                        LOG_ERROR("incomplete vFlashErase packet received, dropping connection");
                        return ERROR_SERVER_REMOTE_CLOSED;
                }

                addr = strtoul(parse, &parse, 16);

                if (*(parse++) != ',' || *parse == '\0')
                {
                        LOG_ERROR("incomplete vFlashErase packet received, dropping connection");
                        return ERROR_SERVER_REMOTE_CLOSED;
                }

                length = strtoul(parse, &parse, 16);

                if (*parse != '\0')
                {
                        LOG_ERROR("incomplete vFlashErase packet received, dropping connection");
                        return ERROR_SERVER_REMOTE_CLOSED;
                }

                /* assume all sectors need erasing - stops any problems
                 * when flash_write is called multiple times */
                flash_set_dirty();

                /* perform any target specific operations before the erase */
                target_call_event_callbacks(gdb_service->target, TARGET_EVENT_GDB_FLASH_ERASE_START);
                result = flash_erase_address_range(gdb_service->target, addr, length );
                target_call_event_callbacks(gdb_service->target, TARGET_EVENT_GDB_FLASH_ERASE_END);

                /* perform erase */
                if (result != ERROR_OK)
                {
                        /* GDB doesn't evaluate the actual error number returned,
                         * treat a failed erase as an I/O error
                         */
                        gdb_send_error(connection, EIO);
                        LOG_ERROR("flash_erase returned %i", result);
                }
                else
                        gdb_put_packet(connection, "OK", 2);

                return ERROR_OK;
        }

        if (strstr(packet, "vFlashWrite:"))
        {
                int retval;
                unsigned long addr;
                unsigned long length;
                char *parse = packet + 12;

                if (*parse == '\0')
                {
                        LOG_ERROR("incomplete vFlashErase packet received, dropping connection");
                        return ERROR_SERVER_REMOTE_CLOSED;
                }
                addr = strtoul(parse, &parse, 16);
                if (*(parse++) != ':')
                {
                        LOG_ERROR("incomplete vFlashErase packet received, dropping connection");
                        return ERROR_SERVER_REMOTE_CLOSED;
                }
                length = packet_size - (parse - packet);

                /* create a new image if there isn't already one */
                if (gdb_connection->vflash_image == NULL)
                {
                        gdb_connection->vflash_image = malloc(sizeof(image_t));
                        image_open(gdb_connection->vflash_image, "", "build");
                }

                /* create new section with content from packet buffer */
                if((retval = image_add_section(gdb_connection->vflash_image, addr, length, 0x0, (u8*)parse)) != ERROR_OK)
                {
                        return retval;
                }

                gdb_put_packet(connection, "OK", 2);

                return ERROR_OK;
        }

        if (!strcmp(packet, "vFlashDone"))
        {
                u32 written;

                /* process the flashing buffer. No need to erase as GDB
                 * always issues a vFlashErase first. */
                target_call_event_callbacks(gdb_service->target, TARGET_EVENT_GDB_FLASH_WRITE_START);
                result = flash_write(gdb_service->target, gdb_connection->vflash_image, &written, 0);
                target_call_event_callbacks(gdb_service->target, TARGET_EVENT_GDB_FLASH_WRITE_END);
                if ( result != ERROR_OK)
                {
                        if (result == ERROR_FLASH_DST_OUT_OF_BANK)
                                gdb_put_packet(connection, "E.memtype", 9);
                        else
                                gdb_send_error(connection, EIO);
                        }
                else
                {
                        LOG_DEBUG("wrote %u bytes from vFlash image to flash", written);
                        gdb_put_packet(connection, "OK", 2);
                }

                image_close(gdb_connection->vflash_image);
                free(gdb_connection->vflash_image);
                gdb_connection->vflash_image = NULL;

                return ERROR_OK;
        }

        gdb_put_packet(connection, "", 0);
        return ERROR_OK;
}

int gdb_detach(connection_t *connection, target_t *target)
{

        switch( detach_mode )
        {
                case GDB_DETACH_RESUME:
                        target_handle_event( target, TARGET_EVENT_OLD_pre_resume );
                        target_resume(target, 1, 0, 1, 0);
                        break;

                case GDB_DETACH_RESET:
                        /* FIX?? make this configurable?? */
                        target_process_reset(connection->cmd_ctx, RESET_HALT);
                        break;

                case GDB_DETACH_HALT:
                        target_halt(target);
                        break;

                case GDB_DETACH_NOTHING:
                        break;
        }

        gdb_put_packet(connection, "OK", 2);
        return ERROR_OK;
}

static void gdb_log_callback(void *priv, const char *file, int line,
                const char *function, const char *string)
{
        connection_t *connection = priv;
        gdb_connection_t *gdb_con = connection->priv;

        if (gdb_con->busy)
        {
                /* do not reply this using the O packet */
                return;
        }

        gdb_output_con(connection, string);
}

/* Do not allocate this on the stack */
char gdb_packet_buffer[GDB_BUFFER_SIZE];

static void gdb_sig_halted(connection_t *connection)
{
        char sig_reply[4];
        snprintf(sig_reply, 4, "T%2.2x", 2);
        gdb_put_packet(connection, sig_reply, 3);

}

int gdb_input_inner(connection_t *connection)
{
        gdb_service_t *gdb_service = connection->service->priv;
        target_t *target = gdb_service->target;
        char *packet=gdb_packet_buffer;
        int packet_size;
        int retval;
        gdb_connection_t *gdb_con = connection->priv;
        static int extended_protocol = 0;

        /* drain input buffer */
        do
        {
                packet_size = GDB_BUFFER_SIZE-1;
                if ((retval = gdb_get_packet(connection, packet, &packet_size)) != ERROR_OK)
                {
                        return retval;
                }

                /* terminate with zero */
                packet[packet_size] = 0;

                if( LOG_LEVEL_IS( LOG_LVL_DEBUG ) ){
                        if( packet[0] == 'X' ){
                                // binary packets spew junk into the debug log stream
                                char buf[ 50 ];
                                int x;
                                for( x = 0 ; (x < 49) && (packet[x] != ':') ; x++ ){
                                        buf[x] = packet[x];
                                }
                                buf[x] = 0;
                                LOG_DEBUG("received packet: '%s:<binary-data>'", buf );
                        } else {
                                LOG_DEBUG("received packet: '%s'", packet );
                        }
                }

                if (packet_size > 0)
                {
                        retval = ERROR_OK;
                        switch (packet[0])
                        {
                                case 'H':
                                        /* Hct... -- set thread
                                         * we don't have threads, send empty reply */
                                        gdb_put_packet(connection, NULL, 0);
                                        break;
                                case 'q':
                                case 'Q':
                                        retval = gdb_query_packet(connection, target, packet, packet_size);
                                        break;
                                case 'g':
                                        retval = gdb_get_registers_packet(connection, target, packet, packet_size);
                                        break;
                                case 'G':
                                        retval = gdb_set_registers_packet(connection, target, packet, packet_size);
                                        break;
                                case 'p':
                                        retval = gdb_get_register_packet(connection, target, packet, packet_size);
                                        break;
                                case 'P':
                                        retval = gdb_set_register_packet(connection, target, packet, packet_size);
                                        break;
                                case 'm':
                                        retval = gdb_read_memory_packet(connection, target, packet, packet_size);
                                        break;
                                case 'M':
                                        retval = gdb_write_memory_packet(connection, target, packet, packet_size);
                                        break;
                                case 'z':
                                case 'Z':
                                        retval = gdb_breakpoint_watchpoint_packet(connection, target, packet, packet_size);
                                        break;
                                case '?':
                                        gdb_last_signal_packet(connection, target, packet, packet_size);
                                        break;
                                case 'c':
                                case 's':
                                        {
                                                if (target->state != TARGET_HALTED)
                                                {
                                                        /* If the target isn't in the halted state, then we can't
                                                         * step/continue. This might be early setup, etc.
                                                         */
                                                        gdb_sig_halted(connection);
                                                } else
                                                {
                                                        /* We're running/stepping, in which case we can
                                                         * forward log output until the target is halted
                                                         */
                                                        gdb_connection_t *gdb_con = connection->priv;
                                                        gdb_con->frontend_state = TARGET_RUNNING;
                                                        log_add_callback(gdb_log_callback, connection);
                                                        target_call_event_callbacks(target, TARGET_EVENT_GDB_START);
                                                        int retval=gdb_step_continue_packet(connection, target, packet, packet_size);
                                                        if (retval!=ERROR_OK)
                                                        {
                                                                /* we'll never receive a halted condition... issue a false one.. */
                                                                gdb_frontend_halted(target, connection);
                                                        }
                                                }
                                        }
                                        break;
                                case 'v':
                                        retval = gdb_v_packet(connection, target, packet, packet_size);
                                        break;
                                case 'D':
                                        retval = gdb_detach(connection, target);
                                        extended_protocol = 0;
                                        break;
                                case 'X':
                                        if ((retval = gdb_write_memory_binary_packet(connection, target, packet, packet_size)) != ERROR_OK)
                                                return retval;
                                        break;
                                case 'k':
                                        if (extended_protocol != 0)
                                                break;
                                        gdb_put_packet(connection, "OK", 2);
                                        return ERROR_SERVER_REMOTE_CLOSED;
                                case '!':
                                        /* handle extended remote protocol */
                                        extended_protocol = 1;
                                        gdb_put_packet(connection, "OK", 2);
                                        break;
                                case 'R':
                                        /* handle extended restart packet */
                                        breakpoint_clear_target(gdb_service->target);
                                        watchpoint_clear_target(gdb_service->target);
                                        command_run_linef(connection->cmd_ctx, "ocd_gdb_restart %d", get_num_by_target(target));
                                        break;
                                default:
                                        /* ignore unkown packets */
                                        LOG_DEBUG("ignoring 0x%2.2x packet", packet[0]);
                                        gdb_put_packet(connection, NULL, 0);
                                        break;
                        }

                        /* if a packet handler returned an error, exit input loop */
                        if (retval != ERROR_OK)
                                return retval;
                }

                if (gdb_con->ctrl_c)
                {
                        if (target->state == TARGET_RUNNING)
                        {
                                target_halt(target);
                                gdb_con->ctrl_c = 0;
                        }
                }

        } while (gdb_con->buf_cnt > 0);

        return ERROR_OK;
}

int gdb_input(connection_t *connection)
{
        int retval = gdb_input_inner(connection);
        gdb_connection_t *gdb_con = connection->priv;
        if (retval == ERROR_SERVER_REMOTE_CLOSED)
                return retval;

        /* logging does not propagate the error, yet can set the gdb_con->closed flag */
        if (gdb_con->closed)
                return ERROR_SERVER_REMOTE_CLOSED;

        /* we'll recover from any other errors(e.g. temporary timeouts, etc.) */
        return ERROR_OK;
}

int gdb_init(void)
{
        gdb_service_t *gdb_service;
        target_t *target = all_targets;

        if (!target)
        {
                LOG_WARNING("no gdb ports allocated as no target has been specified");
                return ERROR_OK;
        }

        if (gdb_port == 0 && server_use_pipes == 0)
        {
                LOG_WARNING("no gdb port specified, using default port 3333");
                gdb_port = 3333;
        }

        if (server_use_pipes)
        {
                /* only a single gdb connection when using a pipe */

                gdb_service = malloc(sizeof(gdb_service_t));
                gdb_service->target = target;

                add_service("gdb", CONNECTION_PIPE, 0, 1, gdb_new_connection, gdb_input, gdb_connection_closed, gdb_service);

                LOG_DEBUG("gdb service for target %s using pipes", target->type->name);
        }
        else
        {
                while (target)
                {
                        gdb_service = malloc(sizeof(gdb_service_t));
                        gdb_service->target = target;

                        add_service("gdb", CONNECTION_TCP, gdb_port + target->target_number, 1, gdb_new_connection, gdb_input, gdb_connection_closed, gdb_service);

                        LOG_DEBUG("gdb service for target %s at port %i", target->type->name, gdb_port + target->target_number);
                        target = target->next;
                }
        }

        return ERROR_OK;
}

/* daemon configuration command gdb_port */
int handle_gdb_port_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
{
        if (argc == 0)
        {
                command_print(cmd_ctx, "%d", gdb_port);
                return ERROR_OK;
        }

        /* only if the port wasn't overwritten by cmdline */
        if (gdb_port == 0)
                gdb_port = strtoul(args[0], NULL, 0);

        return ERROR_OK;
}

int handle_gdb_detach_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
{
        if (argc == 1)
        {
                if (strcmp(args[0], "resume") == 0)
                {
                        detach_mode = GDB_DETACH_RESUME;
                        return ERROR_OK;
                }
                else if (strcmp(args[0], "reset") == 0)
                {
                        detach_mode = GDB_DETACH_RESET;
                        return ERROR_OK;
                }
                else if (strcmp(args[0], "halt") == 0)
                {
                        detach_mode = GDB_DETACH_HALT;
                        return ERROR_OK;
                }
                else if (strcmp(args[0], "nothing") == 0)
                {
                        detach_mode = GDB_DETACH_NOTHING;
                        return ERROR_OK;
                }
                else
                        LOG_WARNING("invalid gdb_detach configuration directive: %s", args[0]);
        }

        return ERROR_COMMAND_SYNTAX_ERROR;
}

int handle_gdb_memory_map_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
{
        if (argc == 1)
        {
                if (strcmp(args[0], "enable") == 0)
                {
                        gdb_use_memory_map = 1;
                        return ERROR_OK;
                }
                else if (strcmp(args[0], "disable") == 0)
                {
                        gdb_use_memory_map = 0;
                        return ERROR_OK;
                }
                else
                        LOG_WARNING("invalid gdb_memory_map configuration directive %s", args[0]);
        }

        return ERROR_COMMAND_SYNTAX_ERROR;
}

int handle_gdb_flash_program_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
{
        if (argc == 1)
        {
                if (strcmp(args[0], "enable") == 0)
                {
                        gdb_flash_program = 1;
                        return ERROR_OK;
                }
                else if (strcmp(args[0], "disable") == 0)
                {
                        gdb_flash_program = 0;
                        return ERROR_OK;
                }
                else
                        LOG_WARNING("invalid gdb_flash_program configuration directive: %s", args[0]);
        }

        return ERROR_COMMAND_SYNTAX_ERROR;
}

int handle_gdb_report_data_abort_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
{
        if (argc == 1)
        {
                if (strcmp(args[0], "enable") == 0)
                {
                        gdb_report_data_abort = 1;
                        return ERROR_OK;
                }
                else if (strcmp(args[0], "disable") == 0)
                {
                        gdb_report_data_abort = 0;
                        return ERROR_OK;
                }
                else
                        LOG_WARNING("invalid gdb_report_data_abort configuration directive: %s", args[0]);
        }

        return ERROR_COMMAND_SYNTAX_ERROR;
}

/* gdb_breakpoint_override */
int handle_gdb_breakpoint_override_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
{
        if (argc == 0)
        {

        } else if (argc==1)
        {
                gdb_breakpoint_override = 1;
                if (strcmp(args[0], "hard")==0)
                {
                        gdb_breakpoint_override_type=BKPT_HARD;
                } else if (strcmp(args[0], "soft")==0)
                {
                        gdb_breakpoint_override_type=BKPT_SOFT;
                } else if (strcmp(args[0], "disable") == 0)
                {
                        gdb_breakpoint_override = 0;
                }
        } else
        {
                return ERROR_COMMAND_SYNTAX_ERROR;
        }
        if (gdb_breakpoint_override)
        {
                LOG_USER("force %s breakpoints", (gdb_breakpoint_override_type==BKPT_HARD)?"hard":"soft");
        } else
        {
                LOG_USER("breakpoint type is not overriden");
        }

        return ERROR_OK;
}

int gdb_register_commands(command_context_t *command_context)
{
        register_command(command_context, NULL, "gdb_port", handle_gdb_port_command,
                        COMMAND_ANY, "daemon configuration command gdb_port");
        register_command(command_context, NULL, "gdb_detach", handle_gdb_detach_command,
                        COMMAND_CONFIG, "");
        register_command(command_context, NULL, "gdb_memory_map", handle_gdb_memory_map_command,
                        COMMAND_CONFIG, "enable or disable memory map");
        register_command(command_context, NULL, "gdb_flash_program", handle_gdb_flash_program_command,
                        COMMAND_CONFIG, "enable or disable flash program");
        register_command(command_context, NULL, "gdb_report_data_abort", handle_gdb_report_data_abort_command,
                        COMMAND_CONFIG, "enable or disable report data");
        register_command(command_context, NULL, "gdb_breakpoint_override", handle_gdb_breakpoint_override_command,
                        COMMAND_EXEC, "hard/soft/disable - force breakpoint type for gdb 'break' commands."
                        "The raison d'etre for this option is to support GDB GUI's without "
                        "a hard/soft breakpoint concept where the default OpenOCD behaviour "
                        "is not sufficient");
        return ERROR_OK;
}