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Kev Sheldrake

Bps - Breakpoint Shenanigans

Download

Tool: bps.0.4.tgz | bps.0.3.tgz
Slides: bps.0.3.pdf

Overview

The idea is to automate some of the things I use gdb for, namely repeatedly breaking on certain addresses and displaying the contents of registers and memory locations, and automatically continuing.

Breakpoints can be specified as either addresses or function names; display information can be contents of registers, or the contents of buffers pointed to by addresses or registers, with offsets. Buffers need to have the format specified - b(ytes), h(alfwords), w(ords), s(tring); size (not for string); and an optional offset. For each breakpoint you can specify the maximum number of times to break on it. You can also specify a function or address to hit before enabling the breakpoints.

If a count is specified for a breakpoint, then it will trigger any specified actions after the specified number of times that breakpoint is hit; the breakpoint will then be disabled. If a count is not specified, then the breakpoint will trigger any specified actions every time the breakpoint is hit.

Breakpoint actions are: enable or disable any number of breakpoints, including itself (by 1-indexed count of breakpoints in the order specified on the command line); kill the process that triggered the breakpoint; and enable or disable copy of breakpoints on fork or thread creation. Breakpoint actions that enable or disable breakpoints can either be local or global, meaning they affect either the current process or thread or they affect all processes and threads.

Program output defaults to stdout, but can be redirected to either stderr or a named pipe.

Supported platforms

32bit x86 (Arch) linux
32bit ARM (Arch) linux (ARMv4-ARMv6 with Thumb support)
32bit MIPSEL (Debian7) linux

Expecting it to work on any other platforms is very optimistic of you.
MIPS port in the pipeline.


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