]> git.sur5r.net Git - openocd/blobdiff - src/server/gdb_server.c
- added support for Intel/Marvel PXA27x (XScale) targets
[openocd] / src / server / gdb_server.c
index b0c0996119031af4590862443b08d5c69bd5f3da..34b66050791a6215fd462eef863be04322b2d8c9 100644 (file)
  *   Free Software Foundation, Inc.,                                       *
  *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
  ***************************************************************************/
+#ifdef HAVE_CONFIG_H
 #include "config.h"
+#endif
+
+#include "replacements.h"
 
 #include "gdb_server.h"
 
 #include <unistd.h>
 #include <stdlib.h>
 
-#ifndef HAVE_STRNDUP
-#include <stdio.h>
-char* strndup(const char *s, size_t n)
-{
-       size_t len = strnlen (s, n);
-       char *new = (char *) malloc (len + 1);
-
-       if (new == NULL)
-               return NULL;
-
-       new[len] = '\0';
-       return (char *) memcpy (new, s, len);
-}
-#endif
-
 #if 0
 #define _DEBUG_GDB_IO_
 #endif
@@ -93,11 +82,26 @@ int gdb_get_char(connection_t *connection, int* next_char)
                return ERROR_OK;
        }
 
-       while ((gdb_con->buf_cnt = read(connection->fd, gdb_con->buffer, GDB_BUFFER_SIZE)) <= 0)
+       while ((gdb_con->buf_cnt = read_socket(connection->fd, gdb_con->buffer, GDB_BUFFER_SIZE)) <= 0)
        {
                if (gdb_con->buf_cnt == 0)
                        return ERROR_SERVER_REMOTE_CLOSED;
                
+#ifdef _WIN32
+               errno = WSAGetLastError();
+
+               switch(errno)
+               {
+                       case WSAEWOULDBLOCK:
+                               usleep(1000);
+                               break;
+                       case WSAECONNABORTED:
+                               return ERROR_SERVER_REMOTE_CLOSED;
+                       default:
+                               ERROR("read: %d", errno);
+                               exit(-1);
+               }
+#else
                switch(errno)
                {
                        case EAGAIN:
@@ -111,6 +115,7 @@ int gdb_get_char(connection_t *connection, int* next_char)
                                ERROR("read: %s", strerror(errno));
                                exit(-1);
                }
+#endif
        }
        
        debug_buffer = malloc(gdb_con->buf_cnt + 1);
@@ -133,6 +138,23 @@ int gdb_get_char(connection_t *connection, int* next_char)
        return ERROR_OK;
 }
 
+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
+       {
+               ERROR("BUG: couldn't put character back");      
+       }
+       
+       return ERROR_OK;
+}
+
 int gdb_put_packet(connection_t *connection, char *buffer, int len)
 {
        int i;
@@ -155,14 +177,14 @@ int gdb_put_packet(connection_t *connection, char *buffer, int len)
                DEBUG("sending packet '$%s#%2.2x'", debug_buffer, my_checksum);
                free(debug_buffer);
                
-               write(connection->fd, "$", 1);
+               write_socket(connection->fd, "$", 1);
                if (len > 0)
-                       write(connection->fd, buffer, len);
-               write(connection->fd, "#", 1);
+                       write_socket(connection->fd, buffer, len);
+               write_socket(connection->fd, "#", 1);
        
                snprintf(checksum, 3, "%2.2x", my_checksum);
        
-               write(connection->fd, checksum, 2);
+               write_socket(connection->fd, checksum, 2);
 
                if ((retval = gdb_get_char(connection, &reply)) != ERROR_OK)
                        return retval;
@@ -202,7 +224,7 @@ int gdb_get_packet(connection_t *connection, char *buffer, int *len)
        int count = 0;
        int retval;
        int first_char = 0;
-       int packet_type;
+       int packet_type = '\0';
        char checksum[3];
        unsigned char my_checksum = 0;
        gdb_connection_t *gdb_con = connection->priv;
@@ -214,6 +236,8 @@ int gdb_get_packet(connection_t *connection, char *buffer, int *len)
                        if ((retval = gdb_get_char(connection, &character)) != ERROR_OK)
                                return retval;
 
+                       DEBUG("character: '%c'", character);
+
                        switch (character)
                        {
                                case '$':
@@ -310,12 +334,12 @@ int gdb_get_packet(connection_t *connection, char *buffer, int *len)
                
                if (my_checksum == strtoul(checksum, NULL, 16))
                {
-                       write (connection->fd, "+", 1);
+                       write_socket(connection->fd, "+", 1);
                        break;
                }
 
                WARNING("checksum error, requesting retransmission");
-               write(connection->fd, "-", 1);
+               write_socket(connection->fd, "-", 1);
        }
 
        return ERROR_OK;
@@ -422,6 +446,9 @@ int gdb_new_connection(connection_t *connection)
        if ((retval = gdb_get_char(connection, &initial_ack)) != ERROR_OK)
                return retval;
                
+       if (initial_ack != '+')
+               gdb_putback_char(connection, initial_ack);
+               
        return ERROR_OK;
 }
 
@@ -437,6 +464,13 @@ int gdb_connection_closed(connection_t *connection)
        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];
@@ -450,7 +484,63 @@ int gdb_last_signal_packet(connection_t *connection, target_t *target, char* pac
        return ERROR_OK;
 }
 
-void gdb_get_registers_packet(connection_t *connection, target_t *target, char* packet, int packet_size)
+void gdb_str_to_target(target_t *target, char *str, char *tstr)
+{
+       int str_len = strlen(str);
+       int i;
+       
+       if (str_len % 2)
+       {
+               ERROR("BUG: gdb value with uneven number of characters encountered: %s", str);
+               exit(-1);
+       }
+       
+       if (target->endianness == TARGET_LITTLE_ENDIAN)
+       {
+               for (i = 0; i < str_len; i+=2)
+               {
+                       tstr[str_len - i - 1] = str[i + 1];
+                       tstr[str_len - i - 2] = str[i];
+               }
+       }
+       else
+       {
+               for (i = 0; i < str_len; i++)
+               {
+                       tstr[i] = str[i];
+               }
+       }       
+}
+
+void gdb_target_to_str(target_t *target, char *tstr, char *str)
+{
+       int str_len = strlen(tstr);
+       int i;
+
+       if (str_len % 2)
+       {
+               ERROR("BUG: gdb value with uneven number of characters encountered");
+               exit(-1);
+       }
+       
+       if (target->endianness == TARGET_LITTLE_ENDIAN)
+       {
+               for (i = 0; i < str_len; i+=2)
+               {
+                       str[str_len - i - 1] = tstr[i + 1];
+                       str[str_len - i - 2] = tstr[i];
+               }
+       }
+       else
+       {
+               for (i = 0; i < str_len; i++)
+               {
+                       str[i] = tstr[i];
+               }
+       }       
+}
+
+int gdb_get_registers_packet(connection_t *connection, target_t *target, char* packet, int packet_size)
 {
        reg_t **reg_list;
        int reg_list_size;
@@ -460,16 +550,17 @@ void gdb_get_registers_packet(connection_t *connection, target_t *target, char*
        char *reg_packet_p;
        int i;
        
-       DEBUG("");
+       DEBUG("-");
 
        if ((retval = target->type->get_gdb_reg_list(target, &reg_list, &reg_list_size)) != ERROR_OK)
        {
                switch (retval)
                {
                        case ERROR_TARGET_NOT_HALTED:
-                               ERROR("gdb requested registers, but we're not halted");
-                               exit(-1);
+                               ERROR("gdb requested registers but we're not halted, dropping connection");
+                               return ERROR_SERVER_REMOTE_CLOSED;
                        default:
+                               /* this is a bug condition - get_gdb_reg_list() may not return any other error */
                                ERROR("BUG: unexpected error returned by get_gdb_reg_list()");
                                exit(-1);
                }
@@ -485,14 +576,10 @@ void gdb_get_registers_packet(connection_t *connection, target_t *target, char*
        
        for (i = 0; i < reg_list_size; i++)
        {
-               int j;
-               char *hex_buf = buf_to_char(reg_list[i]->value, reg_list[i]->size);
+               char *hex_buf = buf_to_str(reg_list[i]->value, reg_list[i]->size, 16);
                DEBUG("hex_buf: %s", hex_buf);
-               for (j = CEIL(reg_list[i]->size, 8) * 2; j > 0; j -= 2)
-               {
-                       *reg_packet_p++ = hex_buf[j - 2];
-                       *reg_packet_p++ = hex_buf[j - 1];
-               }
+               gdb_str_to_target(target, hex_buf, reg_packet_p);
+               reg_packet_p += CEIL(reg_list[i]->size, 8) * 2;
                free(hex_buf);
        }
 
@@ -503,9 +590,12 @@ void gdb_get_registers_packet(connection_t *connection, target_t *target, char*
        gdb_put_packet(connection, reg_packet, CEIL(reg_packet_size, 8) * 2);
        free(reg_packet);
        
+       free(reg_list);
+       
+       return ERROR_OK;
 }
 
-void gdb_set_registers_packet(connection_t *connection, target_t *target, char *packet, int packet_size)
+int gdb_set_registers_packet(connection_t *connection, target_t *target, char *packet, int packet_size)
 {
        int i;
        reg_t **reg_list;
@@ -513,7 +603,7 @@ void gdb_set_registers_packet(connection_t *connection, target_t *target, char *
        int retval;
        char *packet_p;
        
-       DEBUG("");
+       DEBUG("-");
 
        /* skip command character */
        packet++;
@@ -521,8 +611,8 @@ void gdb_set_registers_packet(connection_t *connection, target_t *target, char *
 
        if (packet_size % 2)
        {
-               WARNING("GDB set_registers packet with uneven characters received");
-               return;
+               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)
@@ -530,9 +620,10 @@ void gdb_set_registers_packet(connection_t *connection, target_t *target, char *
                switch (retval)
                {
                        case ERROR_TARGET_NOT_HALTED:
-                               ERROR("gdb requested registers, but we're not halted");
-                               exit(-1);
+                               ERROR("gdb tried to registers but we're not halted, dropping connection");
+                               return ERROR_SERVER_REMOTE_CLOSED;
                        default:
+                               /* this is a bug condition - get_gdb_reg_list() may not return any other error */
                                ERROR("BUG: unexpected error returned by get_gdb_reg_list()");
                                exit(-1);
                }
@@ -541,34 +632,62 @@ void gdb_set_registers_packet(connection_t *connection, target_t *target, char *
        packet_p = packet;
        for (i = 0; i < reg_list_size; i++)
        {
-               char_to_buf(packet, CEIL(reg_list[i]->size, 8) * 2, reg_list[i]->value, reg_list[i]->size);
-               reg_list[i]->dirty = 1;
+               u8 *bin_buf;
+               char *hex_buf;
+               reg_arch_type_t *arch_type;
+               
+               /* convert from GDB-string (target-endian) to hex-string (big-endian) */
+               hex_buf = malloc(CEIL(reg_list[i]->size, 8) * 2);
+               gdb_target_to_str(target, packet_p, hex_buf);
+               
+               /* convert hex-string to binary buffer */
+               bin_buf = malloc(CEIL(reg_list[i]->size, 8));
+               str_to_buf(hex_buf, CEIL(reg_list[i]->size, 8) * 2, bin_buf, reg_list[i]->size, 16);
+
+               /* get register arch_type, and call set method */       
+               arch_type = register_get_arch_type(reg_list[i]->arch_type);
+               if (arch_type == NULL)
+               {
+                       ERROR("BUG: encountered unregistered arch type");
+                       exit(-1);
+               }
+               arch_type->set(reg_list[i], bin_buf);
+
+               /* advance packet pointer */            
+               packet_p += (CEIL(reg_list[i]->size, 8) * 2);
+               
+               free(bin_buf);
+               free(hex_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;
 }
 
-void gdb_get_register_packet(connection_t *connection, target_t *target, char *packet, int packet_size)
+int gdb_get_register_packet(connection_t *connection, target_t *target, char *packet, int packet_size)
 {
-       char *hex_buf;
        char *reg_packet;
-       char *reg_packet_p;
        int reg_num = strtoul(packet + 1, NULL, 16);
        reg_t **reg_list;
        int reg_list_size;
        int retval;
-       int i;
+       char *hex_buf;
        
-       DEBUG("");
+       DEBUG("-");
        
        if ((retval = target->type->get_gdb_reg_list(target, &reg_list, &reg_list_size)) != ERROR_OK)
        {
                switch (retval)
                {
                        case ERROR_TARGET_NOT_HALTED:
-                               ERROR("gdb requested registers, but we're not halted");
-                               exit(-1);
+                               ERROR("gdb requested registers but we're not halted, dropping connection");
+                               return ERROR_SERVER_REMOTE_CLOSED;
                        default:
+                               /* this is a bug condition - get_gdb_reg_list() may not return any other error */
                                ERROR("BUG: unexpected error returned by get_gdb_reg_list()");
                                exit(-1);
                }
@@ -580,40 +699,43 @@ void gdb_get_register_packet(connection_t *connection, target_t *target, char *p
                exit(-1);
        }
 
-       hex_buf = buf_to_char(reg_list[reg_num]->value, reg_list[reg_num]->size);
-       reg_packet = reg_packet_p = malloc(CEIL(reg_list[reg_num]->size, 8) * 2);
+       reg_packet = malloc(CEIL(reg_list[reg_num]->size, 8) * 2);
+
+       hex_buf = buf_to_str(reg_list[reg_num]->value, reg_list[reg_num]->size, 16);
        
-       for (i = CEIL(reg_list[reg_num]->size, 8) * 2; i > 0; i -= 2)
-       {
-               *reg_packet_p++ = hex_buf[i - 2];
-               *reg_packet_p++ = hex_buf[i - 1];
-       }
+       gdb_str_to_target(target, hex_buf, reg_packet);
        
        gdb_put_packet(connection, reg_packet, CEIL(reg_list[reg_num]->size, 8) * 2);
        
+       free(reg_list);
        free(reg_packet);
        free(hex_buf);
        
+       return ERROR_OK;
 }
 
-void gdb_set_register_packet(connection_t *connection, target_t *target, char *packet, int packet_size)
+int gdb_set_register_packet(connection_t *connection, target_t *target, char *packet, int packet_size)
 {
        char *separator;
+       char *hex_buf;
+       u8 *bin_buf;
        int reg_num = strtoul(packet + 1, &separator, 16);
        reg_t **reg_list;
        int reg_list_size;
        int retval;
-
-       DEBUG("");
+       reg_arch_type_t *arch_type;
+       
+       DEBUG("-");
        
        if ((retval = target->type->get_gdb_reg_list(target, &reg_list, &reg_list_size)) != ERROR_OK)
        {
                switch (retval)
                {
                        case ERROR_TARGET_NOT_HALTED:
-                               ERROR("gdb requested registers, but we're not halted");
-                               exit(-1);
+                               ERROR("gdb tried to set a register but we're not halted, dropping connection");
+                               return ERROR_SERVER_REMOTE_CLOSED;
                        default:
+                               /* this is a bug condition - get_gdb_reg_list() may not return any other error */
                                ERROR("BUG: unexpected error returned by get_gdb_reg_list()");
                                exit(-1);
                }
@@ -622,23 +744,67 @@ void gdb_set_register_packet(connection_t *connection, target_t *target, char *p
        if (reg_list_size < reg_num)
        {
                ERROR("gdb requested a non-existing register");
-               exit(-1);
+               return ERROR_SERVER_REMOTE_CLOSED;
        }
 
        if (*separator != '=')
        {
-               ERROR("GDB set register packet, but no '=' following the register number");
-               exit(-1);
+               ERROR("GDB 'set register packet', but no '=' following the register number");
+               return ERROR_SERVER_REMOTE_CLOSED;
        }
        
-       char_to_buf(separator + 1, CEIL(reg_list[reg_num]->size, 8) * 2, reg_list[reg_num]->value, reg_list[reg_num]->size);
-       reg_list[reg_num]->dirty = 1;
+       /* convert from GDB-string (target-endian) to hex-string (big-endian) */
+       hex_buf = malloc(CEIL(reg_list[reg_num]->size, 8) * 2);
+       gdb_target_to_str(target, separator + 1, hex_buf);
+       
+       /* convert hex-string to binary buffer */
+       bin_buf = malloc(CEIL(reg_list[reg_num]->size, 8));
+       str_to_buf(hex_buf, CEIL(reg_list[reg_num]->size, 8) * 2, bin_buf, reg_list[reg_num]->size, 16);
+
+       /* get register arch_type, and call set method */       
+       arch_type = register_get_arch_type(reg_list[reg_num]->arch_type);
+       if (arch_type == NULL)
+       {
+               ERROR("BUG: encountered unregistered arch type");
+               exit(-1);
+       }
+       arch_type->set(reg_list[reg_num], bin_buf);
 
        gdb_put_packet(connection, "OK", 2);
 
+       free(bin_buf);
+       free(hex_buf);
+       free(reg_list);
+
+       return ERROR_OK;
 }
 
-void gdb_read_memory_packet(connection_t *connection, target_t *target, char *packet, int packet_size)
+int gdb_memory_packet_error(connection_t *connection, int retval)
+{
+       switch (retval)
+       {
+               case ERROR_TARGET_NOT_HALTED:
+                       ERROR("gdb tried to read memory but we're not halted, dropping connection");
+                       return ERROR_SERVER_REMOTE_CLOSED;
+                       break;
+               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;
+               default:
+                       ERROR("BUG: unexpected error %i", retval);
+                       exit(-1);
+       }
+       
+       return ERROR_OK;
+}
+
+int gdb_read_memory_packet(connection_t *connection, target_t *target, char *packet, int packet_size)
 {
        char *separator;
        u32 addr = 0;
@@ -648,6 +814,7 @@ void gdb_read_memory_packet(connection_t *connection, target_t *target, char *pa
        char *hex_buffer;
 
        int i;
+       int retval;
 
        /* skip command character */
        packet++;
@@ -655,7 +822,10 @@ void gdb_read_memory_packet(connection_t *connection, target_t *target, char *pa
        addr = strtoul(packet, &separator, 16);
        
        if (*separator != ',')
-               return;
+       {
+               ERROR("incomplete read memory packet received, dropping connection");
+               return ERROR_SERVER_REMOTE_CLOSED;
+       }
 
        len = strtoul(separator+1, NULL, 16);
 
@@ -667,35 +837,46 @@ void gdb_read_memory_packet(connection_t *connection, target_t *target, char *pa
        {
                case 4:
                        if ((addr % 4) == 0)
-                               target->type->read_memory(target, addr, 4, 1, buffer);
+                               retval = target->type->read_memory(target, addr, 4, 1, buffer);
                        else
-                               target->type->read_memory(target, addr, 1, len, buffer);
+                               retval = target->type->read_memory(target, addr, 1, len, buffer);
                        break;
                case 2:
                        if ((addr % 2) == 0)
-                               target->type->read_memory(target, addr, 2, 1, buffer);
+                               retval = target->type->read_memory(target, addr, 2, 1, buffer);
                        else
-                               target->type->read_memory(target, addr, 1, len, buffer);
+                               retval = target->type->read_memory(target, addr, 1, len, buffer);
                        break;
                default:
                        if (((addr % 4) == 0) && ((len % 4) == 0))
-                               target->type->read_memory(target, addr, 4, len / 4, buffer);
+                               retval = target->type->read_memory(target, addr, 4, len / 4, buffer);
                        else
-                               target->type->read_memory(target, addr, 1, len, buffer);
+                               retval = target->type->read_memory(target, addr, 1, len, buffer);
        }
 
-       hex_buffer = malloc(len * 2 + 1);
+       if (retval == ERROR_OK)
+       {
+               hex_buffer = malloc(len * 2 + 1);
+               
+               for (i=0; i<len; i++)
+                       snprintf(hex_buffer + 2*i, 3, "%2.2x", buffer[i]);
        
-       for (i=0; i<len; i++)
-               snprintf(hex_buffer + 2*i, 3, "%2.2x", buffer[i]);
-
-       gdb_put_packet(connection, hex_buffer, len * 2);
+               gdb_put_packet(connection, hex_buffer, len * 2);
        
-       free(hex_buffer);
+               free(hex_buffer);
+       }
+       else
+       {
+               if ((retval = gdb_memory_packet_error(connection, retval)) != ERROR_OK)
+                       return retval; 
+       }
+
        free(buffer);
+       
+       return ERROR_OK;
 }
 
-void gdb_write_memory_packet(connection_t *connection, target_t *target, char *packet, int packet_size)
+int gdb_write_memory_packet(connection_t *connection, target_t *target, char *packet, int packet_size)
 {
        char *separator;
        u32 addr = 0;
@@ -704,6 +885,7 @@ void gdb_write_memory_packet(connection_t *connection, target_t *target, char *p
        u8 *buffer;
 
        int i;
+       int retval;
 
        /* skip command character */
        packet++;
@@ -711,12 +893,18 @@ void gdb_write_memory_packet(connection_t *connection, target_t *target, char *p
        addr = strtoul(packet, &separator, 16);
        
        if (*separator != ',')
-               return;
+       {
+               ERROR("incomplete write memory packet received, dropping connection");
+               return ERROR_SERVER_REMOTE_CLOSED;
+       }
 
        len = strtoul(separator+1, &separator, 16);
 
        if (*(separator++) != ':')
-               return;
+       {
+               ERROR("incomplete write memory packet received, dropping connection");
+               return ERROR_SERVER_REMOTE_CLOSED;
+       }
 
        buffer = malloc(len);
 
@@ -729,43 +917,55 @@ void gdb_write_memory_packet(connection_t *connection, target_t *target, char *p
                buffer[i] = tmp;
        }
 
+       retval = ERROR_OK;
        switch (len)
        {
                /* handle sized writes */
                case 4:
                        if ((addr % 4) == 0)
-                               target->type->write_memory(target, addr, 4, 1, buffer);
+                               retval = target->type->write_memory(target, addr, 4, 1, buffer);
                        else
-                               target->type->write_memory(target, addr, 1, len, buffer);
+                               retval = target->type->write_memory(target, addr, 1, len, buffer);
                        break;
                case 2:
                        if ((addr % 2) == 0)
-                               target->type->write_memory(target, addr, 2, 1, buffer);
+                               retval = target->type->write_memory(target, addr, 2, 1, buffer);
                        else
-                               target->type->write_memory(target, addr, 1, len, buffer);
+                               retval = target->type->write_memory(target, addr, 1, len, buffer);
                        break;
                case 3:
                case 1:
-                       target->type->write_memory(target, addr, 1, len, buffer);
+                       retval = target->type->write_memory(target, addr, 1, len, buffer);
                        break;
                /* handle bulk writes */
                default:
-                       target_write_buffer(target, addr, len, buffer);
+                       retval = target_write_buffer(target, addr, len, buffer);
                        break;
        }
 
-       gdb_put_packet(connection, "OK", 2);
+       if (retval == ERROR_OK)
+       {
+               gdb_put_packet(connection, "OK", 2);
+       }
+       else
+       {
+               if ((retval = gdb_memory_packet_error(connection, retval)) != ERROR_OK)
+                       return retval; 
+       }
        
        free(buffer);
+       
+       return ERROR_OK;
 }
 
-void gdb_write_memory_binary_packet(connection_t *connection, target_t *target, char *packet, int packet_size)
+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;
 
        u8 *buffer;
+       int retval;
 
        /* skip command character */
        packet++;
@@ -773,13 +973,20 @@ void gdb_write_memory_binary_packet(connection_t *connection, target_t *target,
        addr = strtoul(packet, &separator, 16);
        
        if (*separator != ',')
-               return;
+       {
+               ERROR("incomplete write memory binary packet received, dropping connection");
+               return ERROR_SERVER_REMOTE_CLOSED;
+       }
 
        len = strtoul(separator+1, &separator, 16);
 
        if (*(separator++) != ':')
-               return;
+       {
+               ERROR("incomplete write memory binary packet received, dropping connection");
+               return ERROR_SERVER_REMOTE_CLOSED;
+       }
 
+       retval = ERROR_OK;
        if( len ) {
                
                buffer = malloc(len);
@@ -792,29 +999,39 @@ void gdb_write_memory_binary_packet(connection_t *connection, target_t *target,
                {
                        case 4:
                                if ((addr % 4) == 0)
-                                       target->type->write_memory(target, addr, 4, 1, buffer);
+                                       retval = target->type->write_memory(target, addr, 4, 1, buffer);
                                else
-                                       target->type->write_memory(target, addr, 1, len, buffer);
+                                       retval = target->type->write_memory(target, addr, 1, len, buffer);
                                break;
                        case 2:
                                if ((addr % 2) == 0)
-                                       target->type->write_memory(target, addr, 2, 1, buffer);
+                                       retval = target->type->write_memory(target, addr, 2, 1, buffer);
                                else
-                                       target->type->write_memory(target, addr, 1, len, buffer);
+                                       retval = target->type->write_memory(target, addr, 1, len, buffer);
                                break;
                        case 3:
                        case 1:
-                               target->type->write_memory(target, addr, 1, len, buffer);
+                               retval = target->type->write_memory(target, addr, 1, len, buffer);
                                break;
                        default:
-                               target_write_buffer(target, addr, len, buffer);
+                               retval = target_write_buffer(target, addr, len, buffer);
                                break;
                }
                
                free(buffer);
        }
 
-       gdb_put_packet(connection, "OK", 2);
+       if (retval == ERROR_OK)
+       {
+               gdb_put_packet(connection, "OK", 2);
+       }
+       else
+       {
+               if ((retval = gdb_memory_packet_error(connection, retval)) != ERROR_OK)
+                       return retval; 
+       }
+       
+       return ERROR_OK;
 }
 
 void gdb_step_continue_packet(connection_t *connection, target_t *target, char *packet, int packet_size)
@@ -822,11 +1039,10 @@ void gdb_step_continue_packet(connection_t *connection, target_t *target, char *
        int current = 0;
        u32 address = 0x0;
 
-       DEBUG("");
+       DEBUG("-");
 
        if (packet_size > 1)
        {
-               u32 address = 0;
                packet[packet_size] = 0;
                address = strtoul(packet + 1, NULL, 16);
        }
@@ -847,17 +1063,36 @@ void gdb_step_continue_packet(connection_t *connection, target_t *target, char *
        }
 }
 
-void gdb_breakpoint_watchpoint_packet(connection_t *connection, target_t *target, char *packet, int packet_size)
+int gdb_bp_wp_packet_error(connection_t *connection, int retval)
+{
+       switch (retval)
+       {
+               case ERROR_TARGET_NOT_HALTED:
+                       ERROR("gdb tried to set a breakpoint but we're not halted, dropping connection");
+                       return ERROR_SERVER_REMOTE_CLOSED;
+                       break;
+               case ERROR_TARGET_RESOURCE_NOT_AVAILABLE:
+                       gdb_send_error(connection, EBUSY);
+                       break;
+               default:
+                       ERROR("BUG: unexpected error %i", retval);
+                       exit(-1);
+       }
+       
+       return ERROR_OK;
+}
+
+int gdb_breakpoint_watchpoint_packet(connection_t *connection, target_t *target, char *packet, int packet_size)
 {
        int type;
-       enum breakpoint_type bp_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;
 
-       DEBUG("");
+       DEBUG("-");
 
        type = strtoul(packet + 1, &separator, 16);
        
@@ -873,12 +1108,18 @@ void gdb_breakpoint_watchpoint_packet(connection_t *connection, target_t *target
                wp_type = WPT_ACCESS;
                
        if (*separator != ',')
-               return;
+       {
+               ERROR("incomplete breakpoint/watchpoint packet received, dropping connection");
+               return ERROR_SERVER_REMOTE_CLOSED;
+       }
 
        address = strtoul(separator+1, &separator, 16);
 
        if (*separator != ',')
-               return;
+       {
+               ERROR("incomplete breakpoint/watchpoint packet received, dropping connection");
+               return ERROR_SERVER_REMOTE_CLOSED;
+       }
 
        size = strtoul(separator+1, &separator, 16);
 
@@ -890,41 +1131,53 @@ void gdb_breakpoint_watchpoint_packet(connection_t *connection, target_t *target
                        {
                                if ((retval = breakpoint_add(target, address, size, bp_type)) != ERROR_OK)
                                {
-                                       if (retval == ERROR_TARGET_RESOURCE_NOT_AVAILABLE)
-                                       {
-                                               gdb_put_packet(connection, "E00", 3);
-                                               break;
-                                       }
+                                       if ((retval = gdb_bp_wp_packet_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);
                        }
-                       gdb_put_packet(connection, "OK", 2);
                        break;
                case 2:
                case 3:
                case 4:
                {
                        if (packet[0] == 'Z')
-                               watchpoint_add(target, address, size, type-2, 0, 0xffffffffu);
+                       {
+                               if ((retval = watchpoint_add(target, address, size, type-2, 0, 0xffffffffu)) != ERROR_OK)
+                               {
+                                       if ((retval = gdb_bp_wp_packet_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);
+                               gdb_put_packet(connection, "OK", 2);
+                       }
                        break;
                }
                default:
                        break;
        }
 
+       return ERROR_OK;
 }
 
 void gdb_query_packet(connection_t *connection, char *packet, int packet_size)
 {
        command_context_t *cmd_ctx = connection->cmd_ctx;
-       gdb_service_t *gdb_service = connection->service->priv;
-       target_t *target = gdb_service->target;
 
        if (strstr(packet, "qRcmd,"))
        {
@@ -973,7 +1226,7 @@ int gdb_input(connection_t *connection)
                                case ERROR_SERVER_REMOTE_CLOSED:
                                        return ERROR_SERVER_REMOTE_CLOSED;
                                default:
-                                       ERROR("unexpected error");
+                                       ERROR("BUG: unexpected error");
                                        exit(-1);
                        }
                }
@@ -985,6 +1238,7 @@ int gdb_input(connection_t *connection)
                
                if (packet_size > 0)
                {
+                       retval = ERROR_OK;
                        switch (packet[0])
                        {
                                case 'H':
@@ -996,26 +1250,26 @@ int gdb_input(connection_t *connection)
                                        gdb_query_packet(connection, packet, packet_size);
                                        break;
                                case 'g':
-                                       gdb_get_registers_packet(connection, target, packet, packet_size);
+                                       retval = gdb_get_registers_packet(connection, target, packet, packet_size);
                                        break;
                                case 'G':
-                                       gdb_set_registers_packet(connection, target, packet, packet_size);
+                                       retval = gdb_set_registers_packet(connection, target, packet, packet_size);
                                        break;
                                case 'p':
-                                       gdb_get_register_packet(connection, target, packet, packet_size);
+                                       retval = gdb_get_register_packet(connection, target, packet, packet_size);
                                        break;
                                case 'P':
-                                       gdb_set_register_packet(connection, target, packet, packet_size);
+                                       retval = gdb_set_register_packet(connection, target, packet, packet_size);
                                        break;
                                case 'm':
-                                       gdb_read_memory_packet(connection, target, packet, packet_size);
+                                       retval = gdb_read_memory_packet(connection, target, packet, packet_size);
                                        break;
                                case 'M':
-                                       gdb_write_memory_packet(connection, target, packet, packet_size);
+                                       retval = gdb_write_memory_packet(connection, target, packet, packet_size);
                                        break;
                                case 'z':
                                case 'Z':
-                                       gdb_breakpoint_watchpoint_packet(connection, target, packet, packet_size);
+                                       retval = gdb_breakpoint_watchpoint_packet(connection, target, packet, packet_size);
                                        break;
                                case '?':
                                        gdb_last_signal_packet(connection, target, packet, packet_size);
@@ -1029,7 +1283,8 @@ int gdb_input(connection_t *connection)
                                        gdb_put_packet(connection, "OK", 2);
                                        break;
                                case 'X':
-                                       gdb_write_memory_binary_packet(connection, target, packet, packet_size);
+                                       if ((retval = gdb_write_memory_binary_packet(connection, target, packet, packet_size)) != ERROR_OK)
+                                               return retval;
                                        break;
                                case 'k':
                                        gdb_put_packet(connection, "OK", 2);
@@ -1040,6 +1295,10 @@ int gdb_input(connection_t *connection)
                                        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)
@@ -1087,6 +1346,7 @@ int gdb_init()
                
                DEBUG("gdb service for target %s at port %i", target->type->name, gdb_port + i);
                
+               i++;
                target = target->next;
        }