* proc: allow simultaneous call injection to multiple goroutines
Changes the call injection code so that we can have multiple call
injections going on at the same time as long as they happen on distinct
goroutines.
* proc: fix EvalExpressionWithCalls for constant expressions
The lack of address of constant expressions would confuse EvalExpressionWithCalls
Fixes#1577
The initial implementation of the 'call' command required the
function call to be the root expression, i.e. something like:
double(3) + 1
was not allowed, because the root expression was the binary operator
'+', not the function call.
With this change expressions like the one above and others are
allowed.
This is the first step necessary to implement nested function calls
(where the result of a function call is used as argument to another
function call).
This is implemented by replacing proc.CallFunction with
proc.EvalExpressionWithCalls. EvalExpressionWithCalls will run
proc.(*EvalScope).EvalExpression in a different goroutine. This
goroutine, the 'eval' goroutine, will communicate with the main
goroutine of the debugger by means of two channels: continueRequest
and continueCompleted.
The eval goroutine evaluates the expression recursively, when
a function call is encountered it takes care of setting up the
function call on the target program and writes a request to the
continueRequest channel, this causes the 'main' goroutine to restart
the target program by calling proc.Continue.
Whenever Continue encounters a breakpoint that belongs to the
function call injection protocol (runtime.debugCallV1 and associated
functions) it writes to continueCompleted which resumes the 'eval'
goroutine.
The 'eval' goroutine takes care of implementing the function call
injection protocol.
When the expression is fully evaluated the 'eval' goroutine will
write a special message to 'continueRequest' signaling that the
expression evaluation is terminated which will cause Continue to
return to the user.
Updates #119
This change splits the BinaryInfo object into a slice of Image objects
containing information about the base executable and each loaded shared
library (note: go plugins are shared libraries).
Delve backens are supposed to call BinaryInfo.AddImage whenever they
detect that a new shared library has been loaded.
Member fields of BinaryInfo that are used to speed up access to dwarf
(Functions, packageVars, consts, etc...) remain part of BinaryInfo and
are updated to reference the correct image object. This simplifies this
change.
This approach has a few shortcomings:
1. Multiple shared libraries can define functions or globals with the
same name and we have no way to disambiguate between them.
2. We don't have a way to handle library unloading.
Both of those affect C shared libraries much more than they affect go
plugins. Go plugins can't be unloaded at all and a lot of name
collisions are prevented by import paths.
There's only one problem that is concerning: if two plugins both import
the same package they will end up with multiple definition for the same
function.
For example if two plugins use fmt.Printf the final in-memory image
(and therefore our BinaryInfo object) will end up with two copies of
fmt.Printf at different memory addresses. If a user types
break fmt.Printf
a breakpoint should be created at *both* locations.
Allowing this is a relatively complex change that should be done in a
different PR than this.
For this reason I consider this approach an acceptable and sustainable
stopgap.
Updates #865
Adds initial support for plugins, this is only the code needed to keep
track of loaded plugins on linux (both native and gdbserial backend).
It does not actually implement support for debugging plugins on linux.
Updates #865
The repository is being switched from the personal account
github.com/derekparker/delve to the organization account
github.com/go-delve/delve. This patch updates imports and docs, while
preserving things which should not be changed such as my name in the
CHANGELOG and in TODO comments.
This patch allows the `trace` CLI subcommand to display return values of
a function. Additionally, it will also display information on where the
function exited, which could also be helpful in determining the path
taken during function execution.
Fixes#388
Add a flag to Stackframe that indicates where the stack frame is the
bottom-most frame of the stack. This allows clients to know whether the
stack trace terminated normally or if it was truncated because the
maximum depth was reached.
Add a truncation message to the 'stack' command.
Adds -defer flag to the stack command that decorates the stack traces
by associating each stack frame with its deferred calls.
Reworks proc.next to use this feature instead of using proc.DeferPC,
laying the groundwork to implement #1240.
Implements the function call injection protocol introduced in go 1.11
by https://go-review.googlesource.com/c/go/+/109699.
This is only the basic support, see TODO comments in pkg/proc/fncall.go
for a list of missing features.
Updates #119
This pull request makes several changes to delve to allow headless
instancess that are started with the --accept-multiclient flag to
keep running even if there is no connected client. Specifically:
1. Makes a headless instance started with --accept-multiclient quit
after one of the clients sends a Detach request (previously they
would never ever quit, which was a bug).
2. Changes proc/gdbserial and proc/native so that they mark the
Process as exited after they detach, even if they did not kill the
process during detach. This prevents bugs such as #1231 where we
attempt to manipulate a target process after we detached from it.
3. On non --accept-multiclient instances do not kill the target
process unless we started it or the client specifically requests
it (previously if the client did not Detach before closing the
connection we would kill the target process unconditionally)
4. Add a -c option to the quit command that detaches from the
headless server after restarting the target.
5. Change terminal so that, when attached to --accept-multiclient,
pressing ^C will prompt the user to either disconnect from the
server or pause the target process. Also extend the exit prompt to
ask if the user wants to keep the headless server running.
Implements #245, #952, #1159, #1231
Displays the return values of the current function when we step out of
it after executing a step, next or stepout command.
Implementation of this feature is tricky: when the function has
returned the return variables are not in scope anymore. Implementing
this feature requires evaluating variables that are out of scope, using
a stack frame that doesn't exist anymore.
We can't calculate the address of these variables when the
next/step/stepout command is initiated either, because between that
point and the time where the stepout breakpoint is actually hit the
goroutine stack could grow and be moved to a different memory address.
Adds a configuration option (show-location-expr) that when activated
will cause the whatis command to also print the DWARF location
expression for a variable.
When there's a error reading the stack trace the call stack itself
could be corrupted and we should return the partial stacktrace that we
have.
Fixes#868
Other debuggers can be instructed to decorate the stacktrace with the
value of SP. Our SP equivalent is the frame offset, since we can add it
to the Stackframe structure without incurring into added costs we
should, so that frontends can use it if they want.
* service/debugger: Restore breakpoints using file:line on restart
Restoring by address can cause the breakpoint to be inserted in the
middle of an instruction if the executable file has changed.
* terminal: Warn of stale executable when printing source
This version preserves the order of requests, allows the
client to switch between API versions and introduces a
way to send notifications to the client (see TODO item at:
proc/proc_linux.go:325).
Fixes#523, #571
This provides a better error message when the user tries to run dlv
debug on a directory that does not contain a main package, when `dlv
exec` is used with a source file.
Additionally the architecture of the executable is checked as suggested
by @alexbrainman in #443.
Fixes#509
* proc: bugfix: StepInto can not function when temp bps exist
* terminal,service: auto-continue during next and step
Make dlv call continue automatically when a breakpoint is hit on a
different goroutine during a next or step operation.
Added API hooks to implement the other solution to this problem (cancel
the next/step operation if a different breakpoint is hit).
Fixes#387
* service/api: Removed unused fields of service/api.Function
* proc/eval: Set return variable name to input expression
* all: fine-grained control of loadValue for better variable printing
Makes proc.(*Variable).loadValue loading parameters configurable
through one extra argument of type LoadConfig.
This interface is also exposed through the API so clients can control
how much of a variable delve should read.
Supported operators:
- All (binary and unary) operators between basic types except <-,
++ and -- (includes & to take the address of an expression)
- Comparison operators between supported compound types
- Typecast of integer constants into pointer types
- struct members
- indexing of arrays, slices and strings
- slicing of arrays, slices and strings
- pointer dereferencing
- true, false and nil constants
Implements #116, #117 and #251
