gdbstub.c File Reference

GDB stub for remote debugging. More...

#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <ctype.h>
#include <byteswap.h>
#include <ipxe/gdbstub.h>

Go to the source code of this file.

Data Structures
struct	gdbstub

Enumerations
enum	{ POSIX_EINVAL = 0x1c , SIZEOF_PAYLOAD = 512 }

Functions
	FILE_LICENCE (GPL2_OR_LATER_OR_UBDL)
	FILE_SECBOOT (FORBIDDEN)
static void	gdbstub_state_new (struct gdbstub *stub, char ch)
static void	gdbstub_state_data (struct gdbstub *stub, char ch)
static void	gdbstub_state_cksum1 (struct gdbstub *stub, char ch)
static void	gdbstub_state_cksum2 (struct gdbstub *stub, char ch)
static void	gdbstub_state_wait_ack (struct gdbstub *stub, char ch)
static uint8_t	gdbstub_from_hex_digit (char ch)
static uint8_t	gdbstub_to_hex_digit (uint8_t b)
static void	gdbstub_from_hex_buf (char *dst, char *src, int lenbytes)
static void	gdbstub_to_hex_buf (char *dst, char *src, int lenbytes)
static uint8_t	gdbstub_cksum (char *data, int len)
static void	gdbstub_tx_packet (struct gdbstub *stub)
static void	gdbstub_send_ok (struct gdbstub *stub)
static void	gdbstub_send_num_packet (struct gdbstub *stub, char reply, int num)
static int	gdbstub_get_packet_args (struct gdbstub *stub, unsigned long *args, int nargs, int *stop_idx)
static void	gdbstub_send_errno (struct gdbstub *stub, int errno)
static void	gdbstub_report_signal (struct gdbstub *stub)
static void	gdbstub_read_regs (struct gdbstub *stub)
static void	gdbstub_write_regs (struct gdbstub *stub)
static void	gdbstub_read_mem (struct gdbstub *stub)
static void	gdbstub_write_mem (struct gdbstub *stub)
static void	gdbstub_continue (struct gdbstub *stub, int single_step)
static void	gdbstub_breakpoint (struct gdbstub *stub)
static void	gdbstub_rx_packet (struct gdbstub *stub)
static void	gdbstub_parse (struct gdbstub *stub, char ch)
void	gdbstub_handler (int signo, gdbreg_t *regs)
	Interrupt handler.
struct gdb_transport *	find_gdb_transport (const char *name)
	Look up GDB transport by name.
void	gdbstub_start (struct gdb_transport *trans)
	Break into the debugger using the given transport.

Variables
static struct gdbstub	stub

Detailed Description

GDB stub for remote debugging.

Definition in file gdbstub.c.

Enumeration Type Documentation

anonymous enum

anonymous enum

Enumerator
POSIX_EINVAL
SIZEOF_PAYLOAD

Definition at line 41 of file gdbstub.c.

     {
        POSIX_EINVAL = 0x1c,  /* used to report bad arguments to GDB */
        SIZEOF_PAYLOAD = 512, /* buffer size of GDB payload data */
};

Function Documentation

FILE_LICENCE()

FILE_LICENCE

(

GPL2_OR_LATER_OR_UBDL

)

FILE_SECBOOT()

FILE_SECBOOT

(

FORBIDDEN

)

gdbstub_state_new()

void gdbstub_state_new ( struct gdbstub * stub, char ch )

static

Definition at line 312 of file gdbstub.c.

                                                                {
        if ( ch == '$' ) {
                stub->len = 0;
                stub->parse = gdbstub_state_data;
        }
}

References ch, gdbstub_state_data(), and stub.

Referenced by gdbstub_state_cksum2(), and gdbstub_state_wait_ack().

gdbstub_state_data()

void gdbstub_state_data ( struct gdbstub * stub, char ch )

static

Definition at line 319 of file gdbstub.c.

                                                                 {
        if ( ch == '#' ) {
                stub->parse = gdbstub_state_cksum1;
        } else if ( ch == '$' ) {
                stub->len = 0; /* retry new packet */
        } else {
                /* If the length exceeds our buffer, let the checksum fail */
                if ( stub->len < SIZEOF_PAYLOAD ) {
                        stub->payload [ stub->len++ ] = ch;
                }
        }
}

References ch, gdbstub_state_cksum1(), SIZEOF_PAYLOAD, and stub.

Referenced by gdbstub_state_new().

gdbstub_state_cksum1()

void gdbstub_state_cksum1 ( struct gdbstub * stub, char ch )

static

Definition at line 332 of file gdbstub.c.

                                                                   {
        stub->cksum1 = gdbstub_from_hex_digit ( ch ) << 4;
        stub->parse = gdbstub_state_cksum2;
}

References ch, gdbstub_from_hex_digit(), gdbstub_state_cksum2(), and stub.

Referenced by gdbstub_state_data().

gdbstub_state_cksum2()

void gdbstub_state_cksum2 ( struct gdbstub * stub, char ch )

static

Definition at line 337 of file gdbstub.c.

                                                                   {
        uint8_t their_cksum;
        uint8_t our_cksum;
 
        stub->parse = gdbstub_state_new;
        their_cksum = stub->cksum1 + gdbstub_from_hex_digit ( ch );
        our_cksum = gdbstub_cksum ( stub->payload, stub->len );
        if ( their_cksum == our_cksum ) {
                stub->trans->send ( "+", 1 );
                if ( stub->len > 0 ) {
                        gdbstub_rx_packet ( stub );
                }
        } else {
                stub->trans->send ( "-", 1 );
        }
}

References ch, gdbstub_cksum(), gdbstub_from_hex_digit(), gdbstub_rx_packet(), gdbstub_state_new(), and stub.

Referenced by gdbstub_state_cksum1().

gdbstub_state_wait_ack()

void gdbstub_state_wait_ack ( struct gdbstub * stub, char ch )

static

Definition at line 354 of file gdbstub.c.

                                                                     {
        if ( ch == '+' ) {
                stub->parse = gdbstub_state_new;
        } else {
                /* This retransmit is very aggressive but necessary to keep
                 * in sync with GDB. */
                gdbstub_tx_packet ( stub );
        }
}

References ch, gdbstub_state_new(), gdbstub_tx_packet(), and stub.

Referenced by gdbstub_tx_packet().

gdbstub_from_hex_digit()

uint8_t gdbstub_from_hex_digit ( char ch )

static

Definition at line 71 of file gdbstub.c.

                                                  {
        return ( isdigit ( ch ) ? ch - '0' : tolower ( ch ) - 'a' + 0xa ) & 0xf;
}

References ch, isdigit(), and tolower().

Referenced by gdbstub_from_hex_buf(), gdbstub_get_packet_args(), gdbstub_state_cksum1(), and gdbstub_state_cksum2().

gdbstub_to_hex_digit()

uint8_t gdbstub_to_hex_digit ( uint8_t b )

static

Definition at line 75 of file gdbstub.c.

                                                  {
        b &= 0xf;
        return ( b < 0xa ? '0' : 'a' - 0xa ) + b;
}

Referenced by gdbstub_send_num_packet(), gdbstub_to_hex_buf(), and gdbstub_tx_packet().

gdbstub_from_hex_buf()

void gdbstub_from_hex_buf ( char * dst, char * src, int lenbytes )

static

Definition at line 85 of file gdbstub.c.

                                                                        {
        if ( lenbytes == 2 && ( ( unsigned long ) dst & 0x1 ) == 0 ) {
                uint16_t i = gdbstub_from_hex_digit ( src [ 2 ] ) << 12 |
                        gdbstub_from_hex_digit ( src [ 3 ] ) << 8 |
                        gdbstub_from_hex_digit ( src [ 0 ] ) << 4 |
                        gdbstub_from_hex_digit ( src [ 1 ] );
                * ( uint16_t * ) dst = cpu_to_le16 ( i );
        } else if ( lenbytes == 4 && ( ( unsigned long ) dst & 0x3 ) == 0 ) {
                uint32_t i = gdbstub_from_hex_digit ( src [ 6 ] ) << 28 |
                        gdbstub_from_hex_digit ( src [ 7 ] ) << 24 |
                        gdbstub_from_hex_digit ( src [ 4 ] ) << 20 |
                        gdbstub_from_hex_digit ( src [ 5 ] ) << 16 |
                        gdbstub_from_hex_digit ( src [ 2 ] ) << 12 |
                        gdbstub_from_hex_digit ( src [ 3 ] ) << 8 |
                        gdbstub_from_hex_digit ( src [ 0 ] ) << 4 |
                        gdbstub_from_hex_digit ( src [ 1 ] );
                * ( uint32_t * ) dst = cpu_to_le32 ( i );
        } else {
                while ( lenbytes-- > 0 ) {
                        *dst++ = gdbstub_from_hex_digit ( src [ 0 ] ) << 4 |
                                gdbstub_from_hex_digit ( src [ 1 ] );
                        src += 2;
                }
        }
}

References cpu_to_le16, cpu_to_le32, gdbstub_from_hex_digit(), and src.

Referenced by gdbstub_write_mem(), and gdbstub_write_regs().

gdbstub_to_hex_buf()

void gdbstub_to_hex_buf ( char * dst, char * src, int lenbytes )

static

Definition at line 111 of file gdbstub.c.

                                                                      {
        if ( lenbytes == 2 && ( ( unsigned long ) src & 0x1 ) == 0 ) {
                uint16_t i = cpu_to_le16 ( * ( uint16_t * ) src );
                dst [ 0 ] = gdbstub_to_hex_digit ( i >> 4 );
                dst [ 1 ] = gdbstub_to_hex_digit ( i );
                dst [ 2 ] = gdbstub_to_hex_digit ( i >> 12 );
                dst [ 3 ] = gdbstub_to_hex_digit ( i >> 8 );
        } else if ( lenbytes == 4 && ( ( unsigned long ) src & 0x3 ) == 0 ) {
                uint32_t i = cpu_to_le32 ( * ( uint32_t * ) src );
                dst [ 0 ] = gdbstub_to_hex_digit ( i >> 4 );
                dst [ 1 ] = gdbstub_to_hex_digit ( i );
                dst [ 2 ] = gdbstub_to_hex_digit ( i >> 12 );
                dst [ 3 ] = gdbstub_to_hex_digit ( i >> 8 );
                dst [ 4 ] = gdbstub_to_hex_digit ( i >> 20 );
                dst [ 5 ] = gdbstub_to_hex_digit ( i >> 16);
                dst [ 6 ] = gdbstub_to_hex_digit ( i >> 28 );
                dst [ 7 ] = gdbstub_to_hex_digit ( i >> 24 );
        } else {
                while ( lenbytes-- > 0 ) {
                        *dst++ = gdbstub_to_hex_digit ( *src >> 4 );
                        *dst++ = gdbstub_to_hex_digit ( *src );
                        src++;
                }
        }
}

References cpu_to_le16, cpu_to_le32, gdbstub_to_hex_digit(), and src.

Referenced by gdbstub_read_mem(), and gdbstub_read_regs().

gdbstub_cksum()

uint8_t gdbstub_cksum ( char * data, int len )

static

Definition at line 137 of file gdbstub.c.

                                                     {
        uint8_t cksum = 0;
        while ( len-- > 0 ) {
                cksum += ( uint8_t ) *data++;
        }
        return cksum;
}

References data, and len.

Referenced by gdbstub_state_cksum2(), and gdbstub_tx_packet().

gdbstub_tx_packet()

void gdbstub_tx_packet ( struct gdbstub * stub )

static

Definition at line 145 of file gdbstub.c.

                                                       {
        uint8_t cksum = gdbstub_cksum ( stub->payload, stub->len );
        stub->buf [ 0 ] = '$';
        stub->buf [ stub->len + 1 ] = '#';
        stub->buf [ stub->len + 2 ] = gdbstub_to_hex_digit ( cksum >> 4 );
        stub->buf [ stub->len + 3 ] = gdbstub_to_hex_digit ( cksum );
        stub->trans->send ( stub->buf, stub->len + 4 );
        stub->parse = gdbstub_state_wait_ack;
}

References gdbstub_cksum(), gdbstub_state_wait_ack(), gdbstub_to_hex_digit(), and stub.

Referenced by gdbstub_breakpoint(), gdbstub_read_mem(), gdbstub_read_regs(), gdbstub_rx_packet(), gdbstub_send_num_packet(), gdbstub_send_ok(), and gdbstub_state_wait_ack().

gdbstub_send_ok()

void gdbstub_send_ok ( struct gdbstub * stub )

static

Definition at line 156 of file gdbstub.c.

                                                     {
        stub->payload [ 0 ] = 'O';
        stub->payload [ 1 ] = 'K';
        stub->len = 2;
        gdbstub_tx_packet ( stub );
}

References gdbstub_tx_packet(), and stub.

Referenced by gdbstub_breakpoint(), gdbstub_rx_packet(), gdbstub_write_mem(), and gdbstub_write_regs().

gdbstub_send_num_packet()

void gdbstub_send_num_packet ( struct gdbstub * stub, char reply, int num )

static

Definition at line 163 of file gdbstub.c.

                                                                                  {
        stub->payload [ 0 ] = reply;
        stub->payload [ 1 ] = gdbstub_to_hex_digit ( ( char ) num >> 4 );
        stub->payload [ 2 ] = gdbstub_to_hex_digit ( ( char ) num );
        stub->len = 3;
        gdbstub_tx_packet ( stub );
}

References gdbstub_to_hex_digit(), gdbstub_tx_packet(), num, and stub.

Referenced by gdbstub_report_signal(), and gdbstub_send_errno().

gdbstub_get_packet_args()

int gdbstub_get_packet_args ( struct gdbstub * stub, unsigned long * args, int nargs, int * stop_idx )

static

Definition at line 172 of file gdbstub.c.

                                                                                                           {
        int i;
        char ch = 0;
        int argc = 0;
        unsigned long val = 0;
        for ( i = 1; i < stub->len && argc < nargs; i++ ) {
                ch = stub->payload [ i ];
                if ( ch == ':' ) {
                        break;
                } else if ( ch == ',' ) {
                        args [ argc++ ] = val;
                        val = 0;
                } else {
                        val = ( val << 4 ) | gdbstub_from_hex_digit ( ch );
                }
        }
        if ( stop_idx ) {
                *stop_idx = i;
        }
        if ( argc < nargs ) {
                args [ argc++ ] = val;
        }
        return ( ( i == stub->len || ch == ':' ) && argc == nargs );
}

References ch, gdbstub_from_hex_digit(), stub, and val.

Referenced by gdbstub_breakpoint(), gdbstub_continue(), gdbstub_read_mem(), and gdbstub_write_mem().

gdbstub_send_errno()

void gdbstub_send_errno ( struct gdbstub * stub, int errno )

static

Definition at line 197 of file gdbstub.c.

                                                                   {
        gdbstub_send_num_packet ( stub, 'E', errno );
}

References errno, gdbstub_send_num_packet(), and stub.

Referenced by gdbstub_breakpoint(), gdbstub_read_mem(), gdbstub_write_mem(), and gdbstub_write_regs().

gdbstub_report_signal()

void gdbstub_report_signal ( struct gdbstub * stub )

static

Definition at line 201 of file gdbstub.c.

                                                           {
        gdbstub_send_num_packet ( stub, 'S', stub->signo );
}

References gdbstub_send_num_packet(), and stub.

Referenced by gdbstub_handler(), and gdbstub_rx_packet().

gdbstub_read_regs()

void gdbstub_read_regs ( struct gdbstub * stub )

static

Definition at line 205 of file gdbstub.c.

                                                       {
        gdbstub_to_hex_buf ( stub->payload, ( char * ) stub->regs, GDBMACH_SIZEOF_REGS );
        stub->len = GDBMACH_SIZEOF_REGS * 2;
        gdbstub_tx_packet ( stub );
}

References GDBMACH_SIZEOF_REGS, gdbstub_to_hex_buf(), gdbstub_tx_packet(), and stub.

Referenced by gdbstub_rx_packet().

gdbstub_write_regs()

void gdbstub_write_regs ( struct gdbstub * stub )

static

Definition at line 211 of file gdbstub.c.

                                                        {
        if ( stub->len != 1 + GDBMACH_SIZEOF_REGS * 2 ) {
                gdbstub_send_errno ( stub, POSIX_EINVAL );
                return;
        }
        gdbstub_from_hex_buf ( ( char * ) stub->regs, &stub->payload [ 1 ], GDBMACH_SIZEOF_REGS );
        gdbstub_send_ok ( stub );
}

References GDBMACH_SIZEOF_REGS, gdbstub_from_hex_buf(), gdbstub_send_errno(), gdbstub_send_ok(), POSIX_EINVAL, and stub.

Referenced by gdbstub_rx_packet().

gdbstub_read_mem()

void gdbstub_read_mem ( struct gdbstub * stub )

static

Definition at line 220 of file gdbstub.c.

                                                      {
        unsigned long args [ 2 ];
        if ( !gdbstub_get_packet_args ( stub, args, sizeof args / sizeof args [ 0 ], NULL ) ) {
                gdbstub_send_errno ( stub, POSIX_EINVAL );
                return;
        }
        args [ 1 ] = ( args [ 1 ] < SIZEOF_PAYLOAD / 2 ) ? args [ 1 ] : SIZEOF_PAYLOAD / 2;
        gdbstub_to_hex_buf ( stub->payload, ( char * ) args [ 0 ], args [ 1 ] );
        stub->len = args [ 1 ] * 2;
        gdbstub_tx_packet ( stub );
}

References gdbstub_get_packet_args(), gdbstub_send_errno(), gdbstub_to_hex_buf(), gdbstub_tx_packet(), NULL, POSIX_EINVAL, SIZEOF_PAYLOAD, and stub.

Referenced by gdbstub_rx_packet().

gdbstub_write_mem()

void gdbstub_write_mem ( struct gdbstub * stub )

static

Definition at line 232 of file gdbstub.c.

                                                       {
        unsigned long args [ 2 ];
        int colon;
        if ( !gdbstub_get_packet_args ( stub, args, sizeof args / sizeof args [ 0 ], &colon ) ||
                        colon >= stub->len || stub->payload [ colon ] != ':' ||
                        ( stub->len - colon - 1 ) % 2 != 0 ) {
                gdbstub_send_errno ( stub, POSIX_EINVAL );
                return;
        }
        gdbstub_from_hex_buf ( ( char * ) args [ 0 ], &stub->payload [ colon + 1 ], ( stub->len - colon - 1 ) / 2 );
        gdbstub_send_ok ( stub );
}

References gdbstub_from_hex_buf(), gdbstub_get_packet_args(), gdbstub_send_errno(), gdbstub_send_ok(), POSIX_EINVAL, and stub.

Referenced by gdbstub_rx_packet().

gdbstub_continue()

void gdbstub_continue ( struct gdbstub * stub, int single_step )

static

Definition at line 245 of file gdbstub.c.

                                                                       {
        gdbreg_t pc;
        if ( stub->len > 1 && gdbstub_get_packet_args ( stub, &pc, 1, NULL ) ) {
                gdbmach_set_pc ( stub->regs, pc );
        }
        gdbmach_set_single_step ( stub->regs, single_step );
        stub->exit_handler = 1;
        /* Reply will be sent when we hit the next breakpoint or interrupt */
}

References gdbmach_set_pc(), gdbmach_set_single_step(), gdbstub_get_packet_args(), NULL, and stub.

Referenced by gdbstub_rx_packet().

gdbstub_breakpoint()

void gdbstub_breakpoint ( struct gdbstub * stub )

static

Definition at line 255 of file gdbstub.c.

                                                        {
        unsigned long args [ 3 ];
        int enable = stub->payload [ 0 ] == 'Z' ? 1 : 0;
        int rc;
 
        if ( !gdbstub_get_packet_args ( stub, args, sizeof args / sizeof args [ 0 ], NULL ) ) {
                gdbstub_send_errno ( stub, POSIX_EINVAL );
                return;
        }
        if ( ( rc = gdbmach_set_breakpoint ( args [ 0 ], args [ 1 ],
                                             args [ 2 ], enable ) ) != 0 ) {
                /* Not supported */
                stub->len = 0;
                gdbstub_tx_packet ( stub );
                return;
        }
        gdbstub_send_ok ( stub );
}

References gdbmach_set_breakpoint(), gdbstub_get_packet_args(), gdbstub_send_errno(), gdbstub_send_ok(), gdbstub_tx_packet(), NULL, POSIX_EINVAL, rc, and stub.

Referenced by gdbstub_rx_packet().

gdbstub_rx_packet()

void gdbstub_rx_packet ( struct gdbstub * stub )

static

Definition at line 274 of file gdbstub.c.

                                                       {
        switch ( stub->payload [ 0 ] ) {
                case '?':
                        gdbstub_report_signal ( stub );
                        break;
                case 'g':
                        gdbstub_read_regs ( stub );
                        break;
                case 'G':
                        gdbstub_write_regs ( stub );
                        break;
                case 'm':
                        gdbstub_read_mem ( stub );
                        break;
                case 'M':
                        gdbstub_write_mem ( stub );
                        break;
                case 'c': /* Continue */
                case 'k': /* Kill */
                case 's': /* Step */
                case 'D': /* Detach */
                        gdbstub_continue ( stub, stub->payload [ 0 ] == 's' );
                        if ( stub->payload [ 0 ] == 'D' ) {
                                gdbstub_send_ok ( stub );
                        }
                        break;
                case 'Z': /* Insert breakpoint */
                case 'z': /* Remove breakpoint */
                        gdbstub_breakpoint ( stub );
                        break;
                default:
                        stub->len = 0;
                        gdbstub_tx_packet ( stub );
                        break;
        }
}

References gdbstub_breakpoint(), gdbstub_continue(), gdbstub_read_mem(), gdbstub_read_regs(), gdbstub_report_signal(), gdbstub_send_ok(), gdbstub_tx_packet(), gdbstub_write_mem(), gdbstub_write_regs(), and stub.

Referenced by gdbstub_state_cksum2().

gdbstub_parse()

void gdbstub_parse ( struct gdbstub * stub, char ch )

static

Definition at line 364 of file gdbstub.c.

                                                            {
        stub->parse ( stub, ch );
}

References ch, and stub.

Referenced by gdbstub_handler().

gdbstub_handler()

void gdbstub_handler	(	int	signo,
		gdbreg_t *	regs )

Interrupt handler.

@signo POSIX signal number @regs CPU register snapshot

Definition at line 372 of file gdbstub.c.

                                                   {
        char packet [ SIZEOF_PAYLOAD + 4 ];
        size_t len, i;
 
        /* A transport must be set up */
        if ( !stub.trans ) {
                return;
        }
 
        stub.signo = signo;
        stub.regs = regs;
        stub.exit_handler = 0;
        gdbstub_report_signal ( &stub );
        while ( !stub.exit_handler && ( len = stub.trans->recv ( packet, sizeof ( packet ) ) ) > 0 ) {
                for ( i = 0; i < len; i++ ) {
                        gdbstub_parse ( &stub, packet [ i ] );
                }
        }
}

References gdbstub_parse(), gdbstub_report_signal(), len, regs, gdbstub::signo, SIZEOF_PAYLOAD, and stub.

Referenced by gdbmach_handler().

find_gdb_transport()

struct gdb_transport * find_gdb_transport

(

const char *

name

)

Look up GDB transport by name.

Parameters

name	Name of transport

Return values

GDB	transport or NULL

Definition at line 392 of file gdbstub.c.

                                                              {
        struct gdb_transport *trans;
 
        for_each_table_entry ( trans, GDB_TRANSPORTS ) {
                if ( strcmp ( trans->name, name ) == 0 ) {
                        return trans;
                }
        }
        return NULL;
}

References for_each_table_entry, GDB_TRANSPORTS, gdb_transport::name, name, NULL, and strcmp().

Referenced by parse_gdb_transport().

gdbstub_start()

void gdbstub_start

(

struct gdb_transport *

trans

)

Break into the debugger using the given transport.

Parameters

trans

GDB transport

Definition at line 403 of file gdbstub.c.

                                                   {
        stub.trans = trans;
        stub.payload = &stub.buf [ 1 ];
        gdbmach_init();
        gdbmach_breakpoint();
}

References gdbmach_breakpoint(), gdbmach_init(), and stub.

Referenced by gdbstub_exec().

Variable Documentation

stub

struct gdbstub stub

static

Initial value:

= {
        .parse = gdbstub_state_new
}

Definition at line 368 of file gdbstub.c.

                             {
        .parse = gdbstub_state_new
};

Referenced by gdbstub_breakpoint(), gdbstub_continue(), gdbstub_get_packet_args(), gdbstub_handler(), gdbstub_parse(), gdbstub_read_mem(), gdbstub_read_regs(), gdbstub_report_signal(), gdbstub_rx_packet(), gdbstub_send_errno(), gdbstub_send_num_packet(), gdbstub_send_ok(), gdbstub_start(), gdbstub_state_cksum1(), gdbstub_state_cksum2(), gdbstub_state_data(), gdbstub_state_new(), gdbstub_state_wait_ack(), gdbstub_tx_packet(), gdbstub_write_mem(), and gdbstub_write_regs().