This PR aims to add support for rr replay and core actions from the DAP layer. This basically encloses the following:
New launch modes: replay and core
The following modes are added:
replay: Replays an rr trace, allowing backwards flows (reverse continue and stepback). Requires a traceDirPath property on launch.json pointing to a valid rr trace directory.
Equivalent to dlv replay <tracedir> command.
core: Replays a core dump file, showing its callstack and the file matching the callsite. Requires a coreFilePath property on launch.json pointing to a valid coredump file.
Equivalent to dlv core <exe> <corefile> command.
Dependencies
To achieve this the following additional changes were made:
Implement the onStepBackRequest and onReverseContinueRequest methods on service/dap
Adapt onLaunchRequest with the requried validations and logic for these new modes
Use CapabilitiesEvent responses to enable the StepBack controls on the supported scenarios (see dicussion here)
Add the corresponding launch.json support on vs code:
Support for replay and core modes golang/vscode-go#1268
Adds features to support default file descriptor redirects for the
target process:
1. A new command line flag '--redirect' and '-r' are added to specify
file redirects for the target process
2. New syntax is added to the 'restart' command to specify file
redirects.
3. Interactive instances will check if stdin/stdout and stderr are
terminals and print a helpful error message if they aren't.
Allows Delve clients to stop a recording midway by sending a
Command('halt')
request.
This is implemented by changing debugger.New to start recording the
process on a separate goroutine while holding the processMutex locked.
By locking the processMutex we ensure that almost all RPC requests will
block until the recording is done, since we can not respond correctly
to any of them.
API calls that do not require manipulating or examining the target
process, such as "IsMulticlient", "SetApiVersion" and
"GetState(nowait=true)" will work while we are recording the process.
Two other internal changes are made to the API: both GetState and
Restart become asynchronous requests, like Command. Restart because
this way it can be interrupted by a StopRecording request if the
rerecord option is passed.
GetState because clients need a call that will block until the
recording is compelted and can also be interrupted with a
StopRecording.
Clients that are uninterested in allowing the user to stop a recording
can ignore this change, since eventually they will make a request to
Delve that will block until the recording is completed.
Clients that wish to support this feature must:
1. call GetState(nowait=false) after connecting to Delve, before any
call that would need to manipulate the target process
2. allow the user to send a StopRecording request during the initial
GetState call
3. allow the user to send a StopRecording request during any subsequent
Restart(rerecord=true) request (if supported).
Implements #1747
* proc,proc/*: move SelectedGoroutine to proc.Target, remove PostInitializationSetup
moves SelectedGoroutine, SwitchThread and SwitchGoroutine to
proc.Target, merges PostInitializationSetup with NewTarget.
* proc,proc/*: add StopReason field to Target
Adds a StopReason field to the Target object describing why the target
process is currently stopped. This will be useful for the DAP server
(which needs to report this reason in one of its requests) as well as
making pull request #1785 (reverse step) conformant to the new
architecture.
* proc: collect NewTarget arguments into a struct
* tests: misc test fixes for go1.14
- math.go is now ambiguous due to changes to the go runtime so specify
that we mean our own math.go in _fixtures
- go list -m requires vendor-mode to be disabled so pass '-mod=' to it
in case user has GOFLAGS=-mod=vendor
- update version of go/packages, required to work with go 1.14 (and
executed go mod vendor)
- Increased goroutine migration in one development version of Go 1.14
revealed a problem with TestCheckpoints in command_test.go and
rr_test.go. The tests were always wrong because Restart(checkpoint)
doesn't change the current thread but we can't assume that when the
checkpoint was taken the current goroutine was running on the same
thread.
* goversion: update maximum supported version
* Makefile: disable testing lldb-server backend on linux with Go 1.14
There seems to be some incompatibility with lldb-server version 6.0.0
on linux and Go 1.14.
* proc/gdbserial: better handling of signals
- if multiple signals are received simultaneously propagate all of them to the
target threads instead of only one.
- debugserver will drop an interrupt request if a target thread simultaneously
receives a signal, handle this situation.
* dwarf/line: normalize backslashes for windows executables
Starting with Go 1.14 the compiler sometimes emits backslashes as well
as forward slashes in debug_line, normalize everything to / for
conformity with the behavior of previous versions.
* proc/native: partial support for Windows async preempt mechanism
See https://github.com/golang/go/issues/36494 for a description of why
full support for 1.14 under windows is problematic.
* proc/native: disable Go 1.14 async preemption on Windows
See https://github.com/golang/go/issues/36494
* pkg/proc: Introduce Target
* pkg/proc: Remove Common.fncallEnabled
Realistically we only block it on recorded backends.
* pkg/proc: Move fncallForG to Target
* pkg/proc: Remove CommonProcess
Remove final bit of functionality stored in CommonProcess and move it to
*Target.
* pkg/proc: Add SupportsFunctionCall to Target
Adds a '-r' option to the 'restart' command (and to the Restart API)
that re-records the target when using rr.
Also moves the code to delete the trace directory inside the gdbserial
package.
If we send a process to foreground while the headless instance may get
a SIGTTOU/SIGTTIN, if not ignored this signal will stop the headless.
It's not clear why this only happens the second time we do this but
that's how it is.
Also removes the direct syscall to TIOCSPGRP and lets the go runtime do
it instead.
Fixes#1279
When gdbserial can not find debugserver or lldb-server the error
message is always the same and it complains about lldb-server not being
found.
This is fine on linux (where the backend is unnecessary) but incomplete
on macOS (where the backend is actually used).
Make the error message clearer so that users who do not bother reading
install instructions are not confused.
The authorization prompt on macOS can take a long time to be
acknowledged by the user, we should keep waiting for a connection as
long as the debugserver instance we launched remains alive.
