Commit d116e813 authored by Damien Hedde's avatar Damien Hedde Committed by Alex Bennée
Browse files

gdbstub: change GDBState.last_packet to GByteArray 



Remove the packet size upper limit by using a GByteArray
instead of a statically allocated array for last_packet.
Thus we can now send big packets.

Also remove the last_packet_len field and use last_packet->len
instead.

Signed-off-by: default avatarDamien Hedde <damien.hedde@greensocs.com>
Reviewed-by: default avatarPhilippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20191211160514.58373-2-damien.hedde@greensocs.com>
Signed-off-by: default avatarAlex Bennée <alex.bennee@linaro.org>
Reviewed-by: default avatarRichard Henderson <richard.henderson@linaro.org>
Message-Id: <20200316172155.971-27-alex.bennee@linaro.org>
parent f4a23e17

gdbstub.c

+21 −18
Original line number Diff line number Diff line
@@ -351,8 +351,7 @@ typedef struct GDBState { 
    int line_buf_index;

    int line_sum; /* running checksum */

    int line_csum; /* checksum at the end of the packet */

    uint8_t last_packet[MAX_PACKET_LENGTH + 4];

    int last_packet_len;

    GByteArray *last_packet;

    int signal;

#ifdef CONFIG_USER_ONLY

    int fd;
@@ -384,6 +383,7 @@ static void init_gdbserver_state(void) 
    gdbserver_state.init = true;

    gdbserver_state.str_buf = g_string_new(NULL);

    gdbserver_state.mem_buf = g_byte_array_sized_new(MAX_PACKET_LENGTH);

    gdbserver_state.last_packet = g_byte_array_sized_new(MAX_PACKET_LENGTH + 4);

}



#ifndef CONFIG_USER_ONLY
@@ -626,28 +626,29 @@ static void hexdump(const char *buf, int len, 
static int put_packet_binary(const char *buf, int len, bool dump)

{

    int csum, i;

    uint8_t *p;

    uint8_t *ps = &gdbserver_state.last_packet[0];

    uint8_t footer[3];



    if (dump && trace_event_get_state_backends(TRACE_GDBSTUB_IO_BINARYREPLY)) {

        hexdump(buf, len, trace_gdbstub_io_binaryreply);

    }



    for(;;) {

        p = ps;

        *(p++) = '$';

        memcpy(p, buf, len);

        p += len;

        g_byte_array_set_size(gdbserver_state.last_packet, 0);

        g_byte_array_append(gdbserver_state.last_packet,

                            (const uint8_t *) "$", 1);

        g_byte_array_append(gdbserver_state.last_packet,

                            (const uint8_t *) buf, len);

        csum = 0;

        for(i = 0; i < len; i++) {

            csum += buf[i];

        }

        *(p++) = '#';

        *(p++) = tohex((csum >> 4) & 0xf);

        *(p++) = tohex((csum) & 0xf);

        footer[0] = '#';

        footer[1] = tohex((csum >> 4) & 0xf);

        footer[2] = tohex((csum) & 0xf);

        g_byte_array_append(gdbserver_state.last_packet, footer, 3);



        gdbserver_state.last_packet_len = p - ps;

        put_buffer(ps, gdbserver_state.last_packet_len);

        put_buffer(gdbserver_state.last_packet->data,

                   gdbserver_state.last_packet->len);



#ifdef CONFIG_USER_ONLY

        i = get_char();
@@ -2812,20 +2813,22 @@ static void gdb_read_byte(uint8_t ch) 
    uint8_t reply;



#ifndef CONFIG_USER_ONLY

    if (gdbserver_state.last_packet_len) {

    if (gdbserver_state.last_packet->len) {

        /* Waiting for a response to the last packet.  If we see the start

           of a new command then abandon the previous response.  */

        if (ch == '-') {

            trace_gdbstub_err_got_nack();

            put_buffer((uint8_t *)gdbserver_state.last_packet, gdbserver_state.last_packet_len);

            put_buffer(gdbserver_state.last_packet->data,

                       gdbserver_state.last_packet->len);

        } else if (ch == '+') {

            trace_gdbstub_io_got_ack();

        } else {

            trace_gdbstub_io_got_unexpected(ch);

        }



        if (ch == '+' || ch == '$')

            gdbserver_state.last_packet_len = 0;

        if (ch == '+' || ch == '$') {

            g_byte_array_set_size(gdbserver_state.last_packet, 0);

        }

        if (ch != '$')

            return;

    }
@@ -3209,7 +3212,7 @@ static int gdb_monitor_write(Chardev *chr, const uint8_t *buf, int len) 
    const char *p = (const char *)buf;

    int max_sz;



    max_sz = (sizeof(gdbserver_state.last_packet) - 2) / 2;

    max_sz = (MAX_PACKET_LENGTH / 2) + 1;

    for (;;) {

        if (len <= max_sz) {

            gdb_monitor_output(p, len);