Fix a bunch of typos.
[openocd.git] / src / server / gdb_server.c
index 8018e6f..77142df 100644 (file)
@@ -2,7 +2,7 @@
  *   Copyright (C) 2005 by Dominic Rath                                    *
  *   Dominic.Rath@gmx.de                                                   *
  *                                                                         *
- *   Copyright (C) 2007-2009 Øyvind Harboe                                 *
+ *   Copyright (C) 2007-2010 Øyvind Harboe                                 *
  *   oyvind.harboe@zylin.com                                               *
  *                                                                         *
  *   Copyright (C) 2008 by Spencer Oliver                                  *
@@ -61,7 +61,12 @@ struct gdb_connection
        bool sync;      /* set flag to true if you want the next stepi to return immediately.
                       allowing GDB to pick up a fresh set of register values from the target
                       without modifying the target state. */
-
+       /* We delay reporting memory write errors until next step/continue or memory
+        * write. This improves performance of gdb load significantly as the GDB packet
+        * can be replied immediately and a new GDB packet will be ready without delay
+        * (ca. 10% or so...).
+        */
+       bool mem_write_error;
 };
 
 
@@ -74,9 +79,9 @@ static struct gdb_connection *current_gdb_connection;
 static int gdb_breakpoint_override;
 static enum breakpoint_type gdb_breakpoint_override_type;
 
-extern int gdb_error(struct connection *connection, int retval);
-static unsigned short gdb_port = 3333;
-static unsigned short gdb_port_next = 0;
+static int gdb_error(struct connection *connection, int retval);
+static const char *gdb_port;
+static const char *gdb_port_next;
 static const char DIGITS[16] = "0123456789abcdef";
 
 static void gdb_log_callback(void *priv, const char *file, unsigned line,
@@ -89,15 +94,17 @@ int gdb_actual_connections;
 /* 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;
+static int gdb_use_memory_map = 1;
 /* enabled by default*/
-int gdb_flash_program = 1;
+static 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;
+ * see the code in gdb_read_memory_packet() for further explanations.
+ * Disabled by default.
+ */
+static int gdb_report_data_abort;
 
-int gdb_last_signal(struct target *target)
+static int gdb_last_signal(struct target *target)
 {
        switch (target->debug_reason)
        {
@@ -117,7 +124,8 @@ int gdb_last_signal(struct target *target)
        }
 }
 
-int check_pending(struct connection *connection, int timeout_s, int *got_data)
+static int check_pending(struct connection *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
@@ -163,9 +171,12 @@ static int gdb_get_char_inner(struct connection *connection, int* next_char)
        struct gdb_connection *gdb_con = connection->priv;
        int retval = ERROR_OK;
 
+#ifdef _DEBUG_GDB_IO_
+       char *debug_buffer;
+#endif
        for (;;)
        {
-               if (connection->service->type == CONNECTION_PIPE)
+               if (connection->service->type != CONNECTION_TCP)
                {
                        gdb_con->buf_cnt = read(connection->fd, gdb_con->buffer, GDB_BUFFER_SIZE);
                }
@@ -284,14 +295,14 @@ static inline int gdb_get_char_fast(struct connection *connection, int* next_cha
 }
 
 
-int gdb_get_char(struct connection *connection, int* next_char)
+static int gdb_get_char(struct connection *connection, int* next_char)
 {
        struct gdb_connection *gdb_con = connection->priv;
        return gdb_get_char_fast(connection, next_char, &gdb_con->buf_p, &gdb_con->buf_cnt);
 }
 
 
-int gdb_putback_char(struct connection *connection, int last_char)
+static int gdb_putback_char(struct connection *connection, int last_char)
 {
        struct gdb_connection *gdb_con = connection->priv;
 
@@ -311,32 +322,22 @@ int gdb_putback_char(struct connection *connection, int last_char)
 /* 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(struct connection *connection, void *data, int len)
+static int gdb_write(struct connection *connection, void *data, int len)
 {
        struct gdb_connection *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 (connection_write(connection, data, len) == len)
        {
-               if (write_socket(connection->fd, data, len) == len)
-               {
-                       return ERROR_OK;
-               }
+               return ERROR_OK;
        }
        gdb_con->closed = 1;
        return ERROR_SERVER_REMOTE_CLOSED;
 }
 
-int gdb_put_packet_inner(struct connection *connection, char *buffer, int len)
+static int gdb_put_packet_inner(struct connection *connection,
+               char *buffer, int len)
 {
        int i;
        unsigned char my_checksum = 0;
@@ -359,7 +360,8 @@ int gdb_put_packet_inner(struct connection *connection, char *buffer, int len)
        int gotdata;
        for (;;)
        {
-               if ((retval = check_pending(connection, 0, &gotdata)) != ERROR_OK)
+               retval = check_pending(connection, 0, &gotdata);
+               if (retval != ERROR_OK)
                        return retval;
                if (!gotdata)
                        break;
@@ -477,7 +479,7 @@ int gdb_put_packet_inner(struct connection *connection, char *buffer, int len)
        return ERROR_OK;
 }
 
-int gdb_put_packet(struct connection *connection, char *buffer, int len)
+static int gdb_put_packet(struct connection *connection, char *buffer, int len)
 {
        struct gdb_connection *gdb_con = connection->priv;
        gdb_con->busy = 1;
@@ -616,7 +618,8 @@ static __inline__ int fetch_packet(struct connection *connection, int *checksum_
        return ERROR_OK;
 }
 
-int gdb_get_packet_inner(struct connection *connection, char *buffer, int *len)
+static int gdb_get_packet_inner(struct connection *connection,
+               char *buffer, int *len)
 {
        int character;
        int retval;
@@ -691,7 +694,7 @@ int gdb_get_packet_inner(struct connection *connection, char *buffer, int *len)
        return ERROR_OK;
 }
 
-int gdb_get_packet(struct connection *connection, char *buffer, int *len)
+static int gdb_get_packet(struct connection *connection, char *buffer, int *len)
 {
        struct gdb_connection *gdb_con = connection->priv;
        gdb_con->busy = 1;
@@ -700,7 +703,7 @@ int gdb_get_packet(struct connection *connection, char *buffer, int *len)
        return retval;
 }
 
-int gdb_output_con(struct connection *connection, const char* line)
+static int gdb_output_con(struct connection *connection, const char* line)
 {
        char *hex_buffer;
        int i, bin_size;
@@ -722,7 +725,7 @@ int gdb_output_con(struct connection *connection, const char* line)
        return retval;
 }
 
-int gdb_output(struct command_context *context, const char* line)
+static int gdb_output(struct command_context *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);
@@ -746,28 +749,29 @@ static void gdb_frontend_halted(struct target *target, struct connection *connec
        if (gdb_connection->frontend_state == TARGET_RUNNING)
        {
                char sig_reply[4];
-               int signal;
+               int signal_var;
 
                /* stop forwarding log packets! */
                log_remove_callback(gdb_log_callback, connection);
 
                if (gdb_connection->ctrl_c)
                {
-                       signal = 0x2;
+                       signal_var = 0x2;
                        gdb_connection->ctrl_c = 0;
                }
                else
                {
-                       signal = gdb_last_signal(target);
+                       signal_var = gdb_last_signal(target);
                }
 
-               snprintf(sig_reply, 4, "T%2.2x", signal);
+               snprintf(sig_reply, 4, "T%2.2x", signal_var);
                gdb_put_packet(connection, sig_reply, 3);
                gdb_connection->frontend_state = TARGET_HALTED;
        }
 }
 
-int gdb_target_callback_event_handler(struct target *target, enum target_event event, void *priv)
+static int gdb_target_callback_event_handler(struct target *target,
+               enum target_event event, void *priv)
 {
        int retval;
        struct connection *connection = priv;
@@ -795,7 +799,7 @@ int gdb_target_callback_event_handler(struct target *target, enum target_event e
        return ERROR_OK;
 }
 
-int gdb_new_connection(struct connection *connection)
+static int gdb_new_connection(struct connection *connection)
 {
        struct gdb_connection *gdb_connection = malloc(sizeof(struct gdb_connection));
        struct gdb_service *gdb_service = connection->service->priv;
@@ -814,6 +818,7 @@ int gdb_new_connection(struct connection *connection)
        gdb_connection->busy = 0;
        gdb_connection->noack_mode = 0;
        gdb_connection->sync = true;
+       gdb_connection->mem_write_error = false;
 
        /* send ACK to GDB for debug request */
        gdb_write(connection, "+", 1);
@@ -828,9 +833,6 @@ int gdb_new_connection(struct connection *connection)
        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);
-
        /* remove the initial ACK from the incoming buffer */
        if ((retval = gdb_get_char(connection, &initial_ack)) != ERROR_OK)
                return retval;
@@ -842,16 +844,43 @@ int gdb_new_connection(struct connection *connection)
                gdb_putback_char(connection, initial_ack);
        target_call_event_callbacks(gdb_service->target, TARGET_EVENT_GDB_ATTACH);
 
+       if (gdb_use_memory_map)
+       {
+               /* Connect must fail if the memory map can't be set up correctly.
+                *
+                * This will cause an auto_probe to be invoked, which is either
+                * a no-op or it will fail when the target isn't ready(e.g. not halted).
+                */
+               int i;
+               for (i = 0; i < flash_get_bank_count(); i++)
+               {
+                       struct flash_bank *p;
+                       retval = get_flash_bank_by_num(i, &p);
+                       if (retval != ERROR_OK)
+                       {
+                               LOG_ERROR("Connect failed. Consider setting up a gdb-attach event for the target to prepare target for GDB connect, or use 'gdb_memory_map disable'.");
+                               return retval;
+                       }
+               }
+       }
+
        gdb_actual_connections++;
        LOG_DEBUG("New GDB Connection: %d, Target %s, state: %s",
                  gdb_actual_connections,
                  target_name(gdb_service->target),
                  target_state_name(gdb_service->target));
 
+       /* DANGER! If we fail subsequently, we must remove this handler,
+        * otherwise we occasionally see crashes as the timer can invoke the
+        * callback fn.
+        *
+        * register callback to be informed about target events */
+       target_register_event_callback(gdb_target_callback_event_handler, connection);
+
        return ERROR_OK;
 }
 
-int gdb_connection_closed(struct connection *connection)
+static int gdb_connection_closed(struct connection *connection)
 {
        struct gdb_service *gdb_service = connection->service->priv;
        struct gdb_connection *gdb_connection = connection->priv;
@@ -898,21 +927,22 @@ int gdb_connection_closed(struct connection *connection)
        return ERROR_OK;
 }
 
-void gdb_send_error(struct connection *connection, uint8_t the_error)
+static void gdb_send_error(struct connection *connection, uint8_t the_error)
 {
        char err[4];
        snprintf(err, 4, "E%2.2X", the_error);
        gdb_put_packet(connection, err, 3);
 }
 
-int gdb_last_signal_packet(struct connection *connection, struct target *target, char* packet, int packet_size)
+static int gdb_last_signal_packet(struct connection *connection,
+               struct target *target, char* packet, int packet_size)
 {
        char sig_reply[4];
-       int signal;
+       int signal_var;
 
-       signal = gdb_last_signal(target);
+       signal_var = gdb_last_signal(target);
 
-       snprintf(sig_reply, 4, "S%2.2x", signal);
+       snprintf(sig_reply, 4, "S%2.2x", signal_var);
        gdb_put_packet(connection, sig_reply, 3);
 
        return ERROR_OK;
@@ -935,7 +965,8 @@ static int gdb_reg_pos(struct target *target, int pos, int len)
  * The format of reg->value is little endian
  *
  */
-void gdb_str_to_target(struct target *target, char *tstr, struct reg *reg)
+static void gdb_str_to_target(struct target *target,
+               char *tstr, struct reg *reg)
 {
        int i;
 
@@ -968,7 +999,8 @@ static int hextoint(int c)
 }
 
 /* copy over in register buffer */
-void gdb_target_to_reg(struct target *target, char *tstr, int str_len, uint8_t *bin)
+static void gdb_target_to_reg(struct target *target,
+               char *tstr, int str_len, uint8_t *bin)
 {
        if (str_len % 2)
        {
@@ -987,7 +1019,8 @@ void gdb_target_to_reg(struct target *target, char *tstr, int str_len, uint8_t *
        }
 }
 
-int gdb_get_registers_packet(struct connection *connection, struct target *target, char* packet, int packet_size)
+static int gdb_get_registers_packet(struct connection *connection,
+               struct target *target, char* packet, int packet_size)
 {
        struct reg **reg_list;
        int reg_list_size;
@@ -1037,7 +1070,8 @@ int gdb_get_registers_packet(struct connection *connection, struct target *targe
        return ERROR_OK;
 }
 
-int gdb_set_registers_packet(struct connection *connection, struct target *target, char *packet, int packet_size)
+static int gdb_set_registers_packet(struct connection *connection,
+               struct target *target, char *packet, int packet_size)
 {
        int i;
        struct reg **reg_list;
@@ -1095,7 +1129,8 @@ int gdb_set_registers_packet(struct connection *connection, struct target *targe
        return ERROR_OK;
 }
 
-int gdb_get_register_packet(struct connection *connection, struct target *target, char *packet, int packet_size)
+static int gdb_get_register_packet(struct connection *connection,
+               struct target *target, char *packet, int packet_size)
 {
        char *reg_packet;
        int reg_num = strtoul(packet + 1, NULL, 16);
@@ -1130,7 +1165,8 @@ int gdb_get_register_packet(struct connection *connection, struct target *target
        return ERROR_OK;
 }
 
-int gdb_set_register_packet(struct connection *connection, struct target *target, char *packet, int packet_size)
+static int gdb_set_register_packet(struct connection *connection,
+               struct target *target, char *packet, int packet_size)
 {
        char *separator;
        uint8_t *bin_buf;
@@ -1176,29 +1212,14 @@ int gdb_set_register_packet(struct connection *connection, struct target *target
        return ERROR_OK;
 }
 
-int gdb_error(struct connection *connection, int retval)
+/* No attempt is made to translate the "retval" to
+ * GDB speak. This has to be done at the calling
+ * site as no mapping really exists.
+ */
+static int gdb_error(struct connection *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;
-       }
-
+       LOG_DEBUG("Reporting %i to GDB as generic error", retval);
+       gdb_send_error(connection, EFAULT);
        return ERROR_OK;
 }
 
@@ -1207,7 +1228,8 @@ int gdb_error(struct connection *connection, int retval)
  *
  * 8191 bytes by the looks of it. Why 8191 bytes instead of 8192?????
  */
-int gdb_read_memory_packet(struct connection *connection, struct target *target, char *packet, int packet_size)
+static int gdb_read_memory_packet(struct connection *connection,
+               struct target *target, char *packet, int packet_size)
 {
        char *separator;
        uint32_t addr = 0;
@@ -1281,7 +1303,8 @@ int gdb_read_memory_packet(struct connection *connection, struct target *target,
        return retval;
 }
 
-int gdb_write_memory_packet(struct connection *connection, struct target *target, char *packet, int packet_size)
+static int gdb_write_memory_packet(struct connection *connection,
+               struct target *target, char *packet, int packet_size)
 {
        char *separator;
        uint32_t addr = 0;
@@ -1338,13 +1361,14 @@ int gdb_write_memory_packet(struct connection *connection, struct target *target
        return retval;
 }
 
-int gdb_write_memory_binary_packet(struct connection *connection, struct target *target, char *packet, int packet_size)
+static int gdb_write_memory_binary_packet(struct connection *connection,
+               struct target *target, char *packet, int packet_size)
 {
        char *separator;
        uint32_t addr = 0;
        uint32_t len = 0;
 
-       int retval;
+       int retval = ERROR_OK;
 
        /* skip command character */
        packet++;
@@ -1365,14 +1389,18 @@ int gdb_write_memory_binary_packet(struct connection *connection, struct target
                return ERROR_SERVER_REMOTE_CLOSED;
        }
 
-       retval = ERROR_OK;
-       if (len)
-       {
-               LOG_DEBUG("addr: 0x%8.8" PRIx32 ", len: 0x%8.8" PRIx32 "", addr, len);
+       struct gdb_connection *gdb_connection = connection->priv;
 
-               retval = target_write_buffer(target, addr, len, (uint8_t*)separator);
+       if (gdb_connection->mem_write_error)
+       {
+               retval = ERROR_FAIL;
+               /* now that we have reported the memory write error, we can clear the condition */
+               gdb_connection->mem_write_error = false;
        }
 
+       /* By replying the packet *immediately* GDB will send us a new packet
+        * while we write the last one to the target.
+        */
        if (retval == ERROR_OK)
        {
                gdb_put_packet(connection, "OK", 2);
@@ -1383,10 +1411,22 @@ int gdb_write_memory_binary_packet(struct connection *connection, struct target
                        return retval;
        }
 
+       if (len)
+       {
+               LOG_DEBUG("addr: 0x%8.8" PRIx32 ", len: 0x%8.8" PRIx32 "", addr, len);
+
+               retval = target_write_buffer(target, addr, len, (uint8_t*)separator);
+               if (retval != ERROR_OK)
+               {
+                       gdb_connection->mem_write_error = true;
+               }
+       }
+
        return ERROR_OK;
 }
 
-int gdb_step_continue_packet(struct connection *connection, struct target *target, char *packet, int packet_size)
+static int gdb_step_continue_packet(struct connection *connection,
+               struct target *target, char *packet, int packet_size)
 {
        int current = 0;
        uint32_t address = 0x0;
@@ -1419,7 +1459,8 @@ int gdb_step_continue_packet(struct connection *connection, struct target *targe
        return retval;
 }
 
-int gdb_breakpoint_watchpoint_packet(struct connection *connection, struct target *target, char *packet, int packet_size)
+static int gdb_breakpoint_watchpoint_packet(struct connection *connection,
+               struct target *target, char *packet, int packet_size)
 {
        int type;
        enum breakpoint_type bp_type = BKPT_SOFT /* dummy init to avoid warning */;
@@ -1523,8 +1564,11 @@ int gdb_breakpoint_watchpoint_packet(struct connection *connection, struct targe
        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, ...)
+/* print out a string and allocate more space as needed,
+ * mainly used for XML at this point
+ */
+static void xml_printf(int *retval, char **xml, int *pos, int *size,
+               const char *fmt, ...)
 {
        if (*retval != ERROR_OK)
        {
@@ -1591,22 +1635,6 @@ static int decode_xfer_read(char *buf, char **annex, int *ofs, unsigned int *len
        return 0;
 }
 
-int gdb_calc_blocksize(struct flash_bank *bank)
-{
-       uint32_t i;
-       uint32_t block_size = 0xffffffff;
-
-       /* loop through all sectors and return smallest sector size */
-
-       for (i = 0; i < (uint32_t)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)
 {
        struct flash_bank *b1, *b2;
@@ -1625,7 +1653,153 @@ static int compare_bank (const void * a, const void * b)
        }
 }
 
-int gdb_query_packet(struct connection *connection, struct target *target, char *packet, int packet_size)
+static int gdb_memory_map(struct connection *connection,
+               struct target *target, char *packet, int packet_size)
+{
+       /* 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.
+        */
+
+       struct flash_bank *p;
+       char *xml = NULL;
+       int size = 0;
+       int pos = 0;
+       int retval = ERROR_OK;
+       struct flash_bank **banks;
+       int offset;
+       int length;
+       char *separator;
+       uint32_t ram_start = 0;
+       int i;
+       int target_flash_banks = 0;
+
+       /* 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 report non-flash
+        * memory as ram (or rather read/write) by default for GDB, since
+        * it has no concept of non-cacheable read/write memory (i/o etc).
+        *
+        * FIXME Most non-flash addresses are *NOT* RAM!  Don't lie.
+        * Current versions of GDB assume unlisted addresses are RAM...
+        */
+       banks = malloc(sizeof(struct flash_bank *)*flash_get_bank_count());
+
+       for (i = 0; i < flash_get_bank_count(); i++) {
+               retval = get_flash_bank_by_num(i, &p);
+               if (retval != ERROR_OK)
+               {
+                       free(banks);
+                       gdb_error(connection, retval);
+                       return retval;
+               }
+               if(p->target == target)
+                       banks[target_flash_banks++] = p;
+       }
+
+       qsort(banks, target_flash_banks, sizeof(struct flash_bank *),
+                       compare_bank);
+
+       for (i = 0; i < flash_get_bank_count(); i++) {
+               int j;
+               unsigned sector_size = 0;
+               uint32_t start, end;
+
+               p = banks[i];
+               start = p->base;
+               end = p->base + p->size;
+
+               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);
+
+               /* Report adjacent groups of same-size sectors.  So for
+                * example top boot CFI flash will list an initial region
+                * with several large sectors (maybe 128KB) and several
+                * smaller ones at the end (maybe 32KB).  STR7 will have
+                * regions with 8KB, 32KB, and 64KB sectors; etc.
+                */
+               for (j = 0; j < p->num_sectors; j++) {
+                       unsigned group_len;
+
+                       /* Maybe start a new group of sectors. */
+                       if (sector_size == 0) {
+                               start = p->base + p->sectors[j].offset;
+                               xml_printf(&retval, &xml, &pos, &size,
+                                       "<memory type=\"flash\" "
+                                               "start=\"0x%x\" ",
+                                       start);
+                               sector_size = p->sectors[j].size;
+                       }
+
+                       /* Does this finish a group of sectors?
+                        * If not, continue an already-started group.
+                        */
+                       if (j == p->num_sectors -1)
+                               group_len = (p->base + p->size) - start;
+                       else if (p->sectors[j + 1].size != sector_size)
+                               group_len = p->base + p->sectors[j + 1].offset
+                                               - start;
+                       else
+                               continue;
+
+                       xml_printf(&retval, &xml, &pos, &size,
+                               "length=\"0x%x\">\n"
+                               "<property name=\"blocksize\">"
+                                       "0x%x</property>\n"
+                               "</memory>\n",
+                               group_len,
+                               sector_size);
+                       sector_size = 0;
+               }
+
+               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_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;
+}
+
+static int gdb_query_packet(struct connection *connection,
+       struct target *target, char *packet, int packet_size)
 {
        struct command_context *cmd_ctx = connection->cmd_ctx;
        struct gdb_connection *gdb_connection = connection->priv;
@@ -1724,112 +1898,9 @@ int gdb_query_packet(struct connection *connection, struct target *target, char
 
                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. */
-
-               struct flash_bank *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.
-                */
-               struct flash_bank **banks = malloc(sizeof(struct flash_bank *)*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(struct flash_bank *), compare_bank);
-
-               uint32_t 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:memory-map:read::")
+                       && (flash_get_bank_count() > 0))
+               return gdb_memory_map(connection, target, packet, packet_size);
        else if (strstr(packet, "qXfer:features:read:"))
        {
                char *xml = NULL;
@@ -1861,7 +1932,7 @@ int gdb_query_packet(struct connection *connection, struct target *target, char
 
                if (retval != ERROR_OK)
                {
-                       gdb_send_error(connection, retval);
+                       gdb_error(connection, retval);
                        return retval;
                }
 
@@ -1881,7 +1952,8 @@ int gdb_query_packet(struct connection *connection, struct target *target, char
        return ERROR_OK;
 }
 
-int gdb_v_packet(struct connection *connection, struct target *target, char *packet, int packet_size)
+static int gdb_v_packet(struct connection *connection,
+               struct target *target, char *packet, int packet_size)
 {
        struct gdb_connection *gdb_connection = connection->priv;
        struct gdb_service *gdb_service = connection->service->priv;
@@ -1928,9 +2000,19 @@ int gdb_v_packet(struct connection *connection, struct target *target, char *pac
                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);
+               target_call_event_callbacks(gdb_service->target,
+                               TARGET_EVENT_GDB_FLASH_ERASE_START);
+
+               /* vFlashErase:addr,length messages require region start and
+                * end to be "block" aligned ... if padding is ever needed,
+                * GDB will have become dangerously confused.
+                */
+               result = flash_erase_address_range(gdb_service->target,
+                               false, addr, length);
+
+               /* perform any target specific operations after the erase */
+               target_call_event_callbacks(gdb_service->target,
+                               TARGET_EVENT_GDB_FLASH_ERASE_END);
 
                /* perform erase */
                if (result != ERROR_OK)
@@ -2018,11 +2100,12 @@ int gdb_v_packet(struct connection *connection, struct target *target, char *pac
        return ERROR_OK;
 }
 
-int gdb_detach(struct connection *connection, struct target *target)
+static int gdb_detach(struct connection *connection, struct target *target)
 {
        struct gdb_service *gdb_service = connection->service->priv;
 
-       target_call_event_callbacks(gdb_service->target, TARGET_EVENT_GDB_DETACH);
+       target_call_event_callbacks(gdb_service->target,
+                       TARGET_EVENT_GDB_DETACH);
 
        return gdb_put_packet(connection, "OK", 2);
 }
@@ -2042,9 +2125,6 @@ static void gdb_log_callback(void *priv, const char *file, unsigned line,
        gdb_output_con(connection, string);
 }
 
-/* Do not allocate this on the stack */
-char gdb_packet_buffer[GDB_BUFFER_SIZE];
-
 static void gdb_sig_halted(struct connection *connection)
 {
        char sig_reply[4];
@@ -2053,8 +2133,11 @@ static void gdb_sig_halted(struct connection *connection)
 
 }
 
-int gdb_input_inner(struct connection *connection)
+static int gdb_input_inner(struct connection *connection)
 {
+       /* Do not allocate this on the stack */
+       static char gdb_packet_buffer[GDB_BUFFER_SIZE];
+
        struct gdb_service *gdb_service = connection->service->priv;
        struct target *target = gdb_service->target;
        char *packet = gdb_packet_buffer;
@@ -2063,14 +2146,23 @@ int gdb_input_inner(struct connection *connection)
        struct gdb_connection *gdb_con = connection->priv;
        static int extended_protocol = 0;
 
-       /* drain input buffer */
+       /* drain input buffer. If one of the packets fail, then an error
+        * packet is replied, if applicable.
+        *
+        * This loop will terminate and the error code is returned.
+        *
+        * The calling fn will check if this error is something that
+        * can be recovered from, or if the connection must be closed.
+        *
+        * If the error is recoverable, this fn is called again to
+        * drain the rest of the buffer.
+        */
        do
        {
                packet_size = GDB_BUFFER_SIZE-1;
-               if ((retval = gdb_get_packet(connection, packet, &packet_size)) != ERROR_OK)
-               {
+               retval = gdb_get_packet(connection, packet, &packet_size);
+               if (retval != ERROR_OK)
                        return retval;
-               }
 
                /* terminate with zero */
                packet[packet_size] = 0;
@@ -2102,48 +2194,70 @@ int gdb_input_inner(struct connection *connection)
                                        break;
                                case 'q':
                                case 'Q':
-                                       retval = gdb_query_packet(connection, target, packet, packet_size);
+                                       retval = gdb_query_packet(connection,
+                                                       target, packet,
+                                                       packet_size);
                                        break;
                                case 'g':
-                                       retval = gdb_get_registers_packet(connection, target, packet, packet_size);
+                                       retval = gdb_get_registers_packet(
+                                                       connection, target,
+                                                       packet, packet_size);
                                        break;
                                case 'G':
-                                       retval = gdb_set_registers_packet(connection, target, packet, packet_size);
+                                       retval = gdb_set_registers_packet(
+                                                       connection, target,
+                                                       packet, packet_size);
                                        break;
                                case 'p':
-                                       retval = gdb_get_register_packet(connection, target, packet, packet_size);
+                                       retval = gdb_get_register_packet(
+                                                       connection, target,
+                                                       packet, packet_size);
                                        break;
                                case 'P':
-                                       retval = gdb_set_register_packet(connection, target, packet, packet_size);
+                                       retval = gdb_set_register_packet(
+                                                       connection, target,
+                                                       packet, packet_size);
                                        break;
                                case 'm':
-                                       retval = gdb_read_memory_packet(connection, target, packet, packet_size);
+                                       retval = gdb_read_memory_packet(
+                                                       connection, target,
+                                                       packet, packet_size);
                                        break;
                                case 'M':
-                                       retval = gdb_write_memory_packet(connection, target, packet, packet_size);
+                                       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);
+                                       gdb_last_signal_packet(
+                                                       connection, target,
+                                                       packet, packet_size);
                                        break;
                                case 'c':
                                case 's':
                                        {
-                                               int retval = ERROR_OK;
-
-                                               struct gdb_connection *gdb_con = connection->priv;
                                                log_add_callback(gdb_log_callback, connection);
 
+                                               if (gdb_con->mem_write_error)
+                                               {
+                                                       LOG_ERROR("Memory write failure!");
+
+                                                       /* now that we have reported the memory write error, we can clear the condition */
+                                                       gdb_con->mem_write_error = false;
+                                               }
+
                                                bool nostep = false;
+                                               bool already_running = false;
                                                if (target->state == TARGET_RUNNING)
                                                {
-                                                       LOG_WARNING("The target is already running. Halt target before stepi/continue.");
-                                                       retval = target_halt(target);
-                                                       if (retval == ERROR_OK)
-                                                               retval = target_wait_state(target, TARGET_HALTED, 100);
+                                                       LOG_WARNING("WARNING! The target is already running. "
+                                                                       "All changes GDB did to registers will be discarded! "
+                                                                       "Waiting for target to halt.");
+                                                       already_running = true;
                                                } else if (target->state != TARGET_HALTED)
                                                {
                                                        LOG_WARNING("The target is not in the halted nor running stated, stepi/continue ignored.");
@@ -2159,7 +2273,7 @@ int gdb_input_inner(struct connection *connection)
                                                }
                                                gdb_con->sync = false;
 
-                                               if ((retval!=ERROR_OK) || nostep)
+                                               if (!already_running && nostep)
                                                {
                                                        /* Either the target isn't in the halted state, then we can't
                                                         * step/continue. This might be early setup, etc.
@@ -2179,24 +2293,35 @@ int gdb_input_inner(struct connection *connection)
                                                         */
                                                        gdb_con->frontend_state = TARGET_RUNNING;
                                                        target_call_event_callbacks(target, TARGET_EVENT_GDB_START);
-                                                       int retval = gdb_step_continue_packet(connection, target, packet, packet_size);
-                                                       if (retval != ERROR_OK)
+
+                                                       if (!already_running)
                                                        {
-                                                               /* we'll never receive a halted condition... issue a false one.. */
-                                                               gdb_frontend_halted(target, connection);
+                                                               /* Here we don't want packet processing to stop even if this fails,
+                                                                * so we use a local variable instead of retval. */
+                                                               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);
+                                       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)
+                                       retval = gdb_write_memory_binary_packet(
+                                                       connection, target,
+                                                       packet, packet_size);
+                                       if (retval != ERROR_OK)
                                                return retval;
                                        break;
                                case 'k':
@@ -2251,7 +2376,7 @@ int gdb_input_inner(struct connection *connection)
        return ERROR_OK;
 }
 
-int gdb_input(struct connection *connection)
+static int gdb_input(struct connection *connection)
 {
        int retval = gdb_input_inner(connection);
        struct gdb_connection *gdb_con = connection->priv;
@@ -2266,56 +2391,40 @@ int gdb_input(struct connection *connection)
        return ERROR_OK;
 }
 
-static int gdb_target_start(struct target *target, uint16_t port)
+static int gdb_target_start(struct target *target, const char *port)
 {
-       bool use_pipes = 0 == port;
        struct gdb_service *gdb_service = malloc(sizeof(struct gdb_service));
        if (NULL == gdb_service)
                return -ENOMEM;
 
        gdb_service->target = target;
 
-       add_service("gdb", use_pipes ? CONNECTION_PIPE : CONNECTION_TCP,
+       return add_service("gdb",
                        port, 1, &gdb_new_connection, &gdb_input,
                        &gdb_connection_closed, gdb_service);
-
-       const char *name = target_name(target);
-       if (use_pipes)
-               LOG_DEBUG("gdb service for target '%s' using pipes", name);
-       else
-               LOG_DEBUG("gdb service for target '%s' on TCP port %u", name, port);
-       return ERROR_OK;
 }
 
-/* FIXME static */
-int gdb_target_add_one(struct target *target)
+static int gdb_target_add_one(struct target *target)
 {
-       if (gdb_port == 0 && server_use_pipes == 0)
-       {
-               LOG_INFO("gdb port disabled");
-               return ERROR_OK;
-       }
-       if (0 == gdb_port_next)
-               gdb_port_next = gdb_port;
-
-       bool use_pipes = server_use_pipes;
-       static bool server_started_with_pipes = false;
-       if (server_started_with_pipes)
-       {
-               LOG_WARNING("gdb service permits one target when using pipes");
-               if (0 == gdb_port)
-                       return ERROR_OK;
-
-               use_pipes = false;
-       }
-
-       int e = gdb_target_start(target, use_pipes ? 0 : gdb_port_next);
-       if (ERROR_OK == e)
+       int retval = gdb_target_start(target, gdb_port_next);
+       if (retval == ERROR_OK)
        {
-               server_started_with_pipes |= use_pipes;
-               gdb_port_next++;
+               long portnumber;
+               /* If we can parse the port number
+                * then we increment the port number for the next target.
+                */
+               char *end;
+               portnumber = strtol(gdb_port_next, &end, 0);
+               if (!*end)
+               {
+                       if (parse_long(gdb_port_next, &portnumber) == ERROR_OK)
+                       {
+                               free((void *)gdb_port_next);
+                               gdb_port_next = alloc_printf("%d", portnumber+1);
+                       }
+               }
        }
-       return e;
+       return retval;
 }
 
 int gdb_target_add_all(struct target *target)
@@ -2360,34 +2469,39 @@ COMMAND_HANDLER(handle_gdb_sync_command)
 /* daemon configuration command gdb_port */
 COMMAND_HANDLER(handle_gdb_port_command)
 {
-       int retval = CALL_COMMAND_HANDLER(server_port_command, &gdb_port);
-       if (ERROR_OK == retval)
-               gdb_port_next = gdb_port;
+       int retval = CALL_COMMAND_HANDLER(server_pipe_command, &gdb_port);
+       if (ERROR_OK == retval) {
+               free((void*)gdb_port_next);
+               gdb_port_next = strdup(gdb_port);
+       }
        return retval;
 }
 
 COMMAND_HANDLER(handle_gdb_memory_map_command)
 {
-       if (CMD_ARGC == 1)
-               COMMAND_PARSE_ENABLE(CMD_ARGV[0], gdb_use_memory_map);
+       if (CMD_ARGC != 1)
+               return ERROR_COMMAND_SYNTAX_ERROR;
 
-       return ERROR_COMMAND_SYNTAX_ERROR;
+       COMMAND_PARSE_ENABLE(CMD_ARGV[0], gdb_use_memory_map);
+       return ERROR_OK;
 }
 
 COMMAND_HANDLER(handle_gdb_flash_program_command)
 {
-       if (CMD_ARGC == 1)
-               COMMAND_PARSE_ENABLE(CMD_ARGV[0], gdb_flash_program);
+       if (CMD_ARGC != 1)
+               return ERROR_COMMAND_SYNTAX_ERROR;
 
-       return ERROR_COMMAND_SYNTAX_ERROR;
+       COMMAND_PARSE_ENABLE(CMD_ARGV[0], gdb_flash_program);
+       return ERROR_OK;
 }
 
 COMMAND_HANDLER(handle_gdb_report_data_abort_command)
 {
-       if (CMD_ARGC == 1)
-               COMMAND_PARSE_ENABLE(CMD_ARGV[0], gdb_report_data_abort);
+       if (CMD_ARGC != 1)
+               return ERROR_COMMAND_SYNTAX_ERROR;
 
-       return ERROR_COMMAND_SYNTAX_ERROR;
+       COMMAND_PARSE_ENABLE(CMD_ARGV[0], gdb_report_data_abort);
+       return ERROR_OK;
 }
 
 /* gdb_breakpoint_override */
@@ -2437,9 +2551,13 @@ static const struct command_registration gdb_command_handlers[] = {
                .name = "gdb_port",
                .handler = handle_gdb_port_command,
                .mode = COMMAND_ANY,
-               .help = "Display or specify base port on which to listen "
-                       "for incoming GDB connections.  "
-                       "No arguments reports GDB port; zero disables.",
+               .help = "Normally gdb listens to a TCP/IP port. Each subsequent GDB "
+                               "server listens for the next port number after the "
+                               "base port number specified. "
+                               "No arguments reports GDB port. \"pipe\" means listen to stdin "
+                               "output to stdout, an integer is base port number, \"disable\" disables "
+                               "port. Any other string is are interpreted as named pipe to listen to. "
+                               "Output pipe is the same name as input pipe, but with 'o' appended.",
                .usage = "[port_num]",
        },
        {
@@ -2466,7 +2584,7 @@ static const struct command_registration gdb_command_handlers[] = {
        {
                .name = "gdb_breakpoint_override",
                .handler = handle_gdb_breakpoint_override_command,
-               .mode = COMMAND_EXEC,
+               .mode = COMMAND_ANY,
                .help = "Display or specify type of breakpoint "
                        "to be used by gdb 'break' commands.",
                .usage = "('hard'|'soft'|'disable')"
@@ -2476,5 +2594,7 @@ static const struct command_registration gdb_command_handlers[] = {
 
 int gdb_register_commands(struct command_context *cmd_ctx)
 {
+       gdb_port = strdup("3333");
+       gdb_port_next = strdup("3333");
        return register_commands(cmd_ctx, NULL, gdb_command_handlers);
 }