luser / tracetree

A tool for capturing the execution of an entire process tree

tracetree

Run a process, ptrace'ing it and all of its children, and print the entire process tree at the end.

Currently only Linux support is implemented.

Examples

Print a process tree in text format to stdout:

$ tracetree /bin/bash -c '/bin/sleep 1; /bin/sleep 1'
16665 bash -c /bin/sleep 1; /bin/sleep 1 [2.004s]
	16666 sleep 1 [1.001s]
	16667 sleep 1 [1.000s]

Print a process tree in JSON format to output.json:

$ tracetree -f json -o output.json /bin/bash -c '/bin/sleep 1; /bin/sleep 1'
$ python -mjson.tool output.json
{
    "children": [
        {
            "children": [],
            "cmdline": [
                "/bin/sleep",
                "1"
            ],
            "ended": "2017-06-22T06:28:58.960384212-04:00",
            "pid": 16727,
            "started": "2017-06-22T06:28:57.959636824-04:00"
        },
        {
            "children": [],
            "cmdline": [
                "/bin/sleep",
                "1"
            ],
            "ended": "2017-06-22T06:28:59.961990469-04:00",
            "pid": 16728,
            "started": "2017-06-22T06:28:58.960849779-04:00"
        }
    ],
    "cmdline": [
        "/bin/bash",
        "-c",
        "/bin/sleep 1; /bin/sleep 1"
    ],
    "ended": "2017-06-22T06:28:59.962407641-04:00",
    "pid": 16726,
    "started": "2017-06-22T06:28:57.958836370-04:00"
}

JSON output can be viewed with this web visualizer:

tracetree's Issues

`thread 'main' panicked at 'Failed to spawn process: Error(Msg("Unexpected process status: Signaled(7771, SIGTERM, false)")`

thread 'main' panicked at 'Failed to spawn process: Error(Msg("Unexpected process status: Signaled(7771, SIGTERM, false)"), State { next_error: None, backtrace: Some(stack backtrace:
   0:     0x55fda50ef0fc - backtrace::backtrace::trace::h58bdbc4722aadbf4
   1:     0x55fda50ef242 - backtrace::capture::Backtrace::new::hde1afc496271e12d
   2:     0x55fda50ae0a6 - error_chain::make_backtrace::hb3affedfab149f41
   3:     0x55fda50ae158 - <error_chain::State as core::default::Default>::default::h0287c2899b6ba4bd
   4:     0x55fda50acbab - <tracetree::errors::Error as core::convert::From<collections::string::String>>::from::hd80ab8e5123d5b17
   5:     0x55fda501eaea - tracetree::ProcessTree::spawn::h318ee82efe85e77e
   6:     0x55fda5020160 - tracetree::main::h0c4d1b8d40bb9fd3
   7:     0x55fda511349a - panic_unwind::__rust_maybe_catch_panic
                        at /checkout/src/libpanic_unwind/lib.rs:98
   8:     0x55fda510ccf8 - std::panicking::try<(),closure>
                        at /checkout/src/libstd/panicking.rs:433
                         - std::panic::catch_unwind<closure,()>
                        at /checkout/src/libstd/panic.rs:361
                         - std::rt::lang_start
                        at /checkout/src/libstd/rt.rs:59
   9:     0x7fd72b3863f0 - __libc_start_main
  10:     0x55fda50175c9 - _start
  11:                0x0 - <unknown>) })', /checkout/src/libcore/result.rs:860
stack backtrace:
   0: std::sys::imp::backtrace::tracing::imp::unwind_backtrace
             at /checkout/src/libstd/sys/unix/backtrace/tracing/gcc_s.rs:49
   1: std::sys_common::backtrace::_print
             at /checkout/src/libstd/sys_common/backtrace.rs:71
   2: std::panicking::default_hook::{{closure}}
             at /checkout/src/libstd/sys_common/backtrace.rs:60
             at /checkout/src/libstd/panicking.rs:355
   3: std::panicking::default_hook
             at /checkout/src/libstd/panicking.rs:371
   4: std::panicking::rust_panic_with_hook
             at /checkout/src/libstd/panicking.rs:549
   5: std::panicking::begin_panic
             at /checkout/src/libstd/panicking.rs:511
   6: std::panicking::begin_panic_fmt
             at /checkout/src/libstd/panicking.rs:495
   7: rust_begin_unwind
             at /checkout/src/libstd/panicking.rs:471
   8: core::panicking::panic_fmt
             at /checkout/src/libcore/panicking.rs:69
   9: core::result::unwrap_failed
  10: tracetree::main
  11: __rust_maybe_catch_panic
             at /checkout/src/libpanic_unwind/lib.rs:98
  12: std::rt::lang_start
             at /checkout/src/libstd/panicking.rs:433
             at /checkout/src/libstd/panic.rs:361
             at /checkout/src/libstd/rt.rs:59
  13: __libc_start_main
  14: _start

This was tracetree ./mach wpt testing/web-platform/tests/compat although on a branch.

Add macOS support

It would be great to have macOS support. ptrace doesn't have the same options there, but I finally found the necessary APIs that should enable this.

Specifically, calling dispatch_source_create with DISPATCH_SOURCE_TYPE_PROC will provide events on fork/exec/exit, which should be sufficient for this tool's needs. Apple has some sample code, and there's also the LLDB source to look at, where I originally stumbled upon this.

Migrate CI to GitHub Actions

Now that Travis CI has ended their free tier, CI should migrate to GitHub Actions. The actions-rs quickstart example is probably a good place to start.

Support Chrome trace viewer format

Chrome's trace viewer has a trace file format. @LegNeato pointed out that buck supports generating that format, and this tool could too. That would mean having access to a much nicer viewing interface!

Add Windows support

Windows provides an API to associate an IO completion port with a Job object, by calling SetInformationJobObject with JobObjectAssociateCompletionPortInformation and passing in a JOBOBJECT_ASSOCIATE_COMPLETION_PORT.

The MSDN docs say the notifications aren't reliable, but don't explain why and I can't find any evidence to support that. I think it's worth trying it out, in any event.