test-gdb-jump

README.md

test-gdb-jump

ex.c

#include <stdlib.h>
#include <stdio.h>

#define CREATE_PAYLOAD(name) \
void name() { \
    for (int i = 0; i < 10; ++i) { \
        printf("Function: %s (%i)\n", __FUNCTION__, i); \
    } \
}

CREATE_PAYLOAD(foo)
CREATE_PAYLOAD(bar)
CREATE_PAYLOAD(baz)

int main(int argc, char **argv)
{
    foo();
    bar();
    baz();

    return EXIT_SUCCESS;
}

jump-gdb.sh

#!/usr/bin/env bash

#
# This script will skip call of "foo" function
#

function call_addr()
{
    objdump -D ./ex | egrep 'callq.*'$1'' | tr -d : | awk '{printf "0x%s", $1}'
}

FOO_CALL_ADDR=$(call_addr foo)
BAR_CALL_ADDR=$(call_addr bar)

gdb \
    -ex "start" \
    -ex "break *$FOO_CALL_ADDR" \
    -ex "continue" \
    -ex "jump *$BAR_CALL_ADDR" \
    -ex "quit" \
    \
    ./ex

make.sh

#!/usr/bin/env bash

#gcc -Wl,--gc-sections -ffunction-sections -g3 -std=c99 -O0 -o ex ex.c
gcc -ffunction-sections -g3 -std=c99 -O0 -o ex ex.c