Evaluates var.method expressions into a variable holding the
corresponding method with the receiver variable as a child, in
preparation for extending CallFunction so that it can call methods.
Changes (*Variable).setValue so that it can be used in CallFunction to
set up the argument frame for the function call, adding the ability to:
- nil nillable types
- set strings to the empty string
- copy from one structure to another (including strings and slices)
- convert any interface type to interface{}
- convert pointer shaped types (map, chan, pointers, and structs
consisting of a single pointer field) to interface{}
This covers all cases where an assignment statement can be evaluated
without allocating memory or calling functions in the target process.
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
Setting the Level field of a logrus logger doesn't actually do anything
since the Level field simply reports the log level of the last log
message emitted on the logger.
The right way to do that is to set logger.Logger.Level.
Also cleans up newline characters from log messages emitted through
logrus and fixes the direction of the arrows in the messages emitted by
rpccommon, which was inconsistent with the arrows of gdbserial.
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
This message is used by clients to determine the port that a headless
instance is using, therefore the format can not change or move to a
different file handle.
Fixes#1245
Implements structured logging via Logrus. This gives us a logger per
boundry that we care about, allowing for easier parsing of logs if users
have more than one log option enabled. Also, cleans up a lot of
conditionals in the code by simply silencing the logger at creation as
opposed to conditionally logging everywhere.
If the application being debugged imports two packages with the same
name (but different paths) there was no way to disambiguate the two,
since the character '/' can not appear inside a go identifier.
By allowing users to use a string literal as the package name a package
path can be specified.
We occasionally receive bug reports from users of VSCode-go and GoLand.
GoLand has its own way of capturing the packet exchange between itself
and delve but VSCode-go (supposedly) doesn't.
So far this hasn't been a problem since all bug reports were obvious
bugs on the plugin or easy to reproduce without VSCode-go, but it might
be helpful in the future to have a way to log the packet exchange
between dlv and a frontend.
This commit adds a --log-output option to enable logging of all rpc
messages and changes service/rpccommon accordingly.
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.
Change the linux verison of proc/native and proc/gdbserial (with
debugserver) so that they let the target process use the terminal when
delve is launched in headless mode.
Windows already worked, proc/gdbserial (with rr) already worked.
I couldn't find a way to make proc/gdbserial (with lldb-server) work.
No tests are added because I can't think of a way to test for
foregroundness of a process.
Fixes#65
Caching the frame in variablesByTag is problematic:
1. accounting for variables that are (partially) stored in registers is
complicated (see issue #1106)
2. for some types (strings, interfaces...) simply creating the Variable
object reads memory, which therefore happens before we can do any
caching.
Instead cache the entire frame when the EvalScope object is created.
The cached range is between the SP value of the current frame and the
CFA of the preceeding frame, if available, or the CFA of the current
frame otherwise.
Fixes#1106
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.
updates vendored version of x86asm, adds a symbol lookup function to
pass to the disassembler.
This will show global symbol names in the disassembly like go tool
objdump does.
debug_info entries can use DW_AT_abstract_origin to inherit the
attributes of another entry, supporting this attribute is necessary to
support DW_TAG_inlined_subroutine.
Go, starting with 1.10, emits DW_TAG_inlined_subroutine entries when
inlining is enabled.
Much like the bug in issue #1031 and commit
f6f6f0bf13e4c708cb501202b83a6327a0f00e31 pointers can also escape to
the heap and then have a zero address (and no children) when we
autodereference.
1. Mark autodereferenced escaped variables with a 0 address as
unreadable.
2. Add guards to the pretty printers for unsafe.Pointer and pointers.
Fixes#1075
* command/terminal: allow restart to change process args
Add -args flag to "restart" command. For example, "restart -args a b c" will
pass args a b c to the new process.
Add "-c" flag to pass the checkpoint name. This is needed to disambiguate the
checkpoint name and arglist.
Reverted unnecessary changes.
* Applied reviewer comments.
Vendored argv.
Change the syntax of restart. When the target is is in recording mode, it always
interprets the args as a checkpoint. Otherwise, it interprets the args as
commandline args. The flag "-args" is still there, to handle the case in which
the user wants to pass an empty args on restart.
* Add restartargs.go.
Change "restart -args" to "restart -noargs" to clarify that this flag is used to
start a process with an empty arg.
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.
So far we have evaluated the locspec "+0" the same way we evaluate all
"+n" locspecs, this means that we turn the current PC into a file:line
pair, then we turn back the file:line into a PC address.
Normally this is harmless, however all autogenerated code returns the
source position "<autogenerated>:1" which resolves back to the very
first autogenerated instruction in the code.
This messes up the behaviour of the "disassemble" command which uses
the locspec "+0" to figure out what code to disassemble if no arguments
are passed.
We should make +0 always resolve to the current PC (of the given scope)
so that clients can use +0 as a default locspec.
When creating a stack trace we should switch between the goroutine
stack and the system stack (where cgo code is executed) as appropriate
to reconstruct the logical stacktrace.
Goroutines that are currently executing on the system stack will have
the SystemStack flag set, frames of the goroutine stack will have a
negative FrameOffset (like always) and frames of the system stack will
have a positive FrameOffset (which is actually just the CFA value for
the frame).
Updates #935
Replace the unsafe.Pointer type of the buf field of channels with the
appropriate array type, allow expressions accessing member field of the
channel struct.
Fixes#962
Conditional breakpoints with unmet conditions would cause next and step
to skip the line.
This breakpoint changes the Kind field of proc.Breakpoint from a single
value to a bit field, each breakpoint object can represent
simultaneously a user breakpoint and one internal breakpoint (of which
we have several different kinds).
The breakpoint condition for internal breakpoints is stored in the new
internalCond field of proc.Breakpoint so that it will not conflict with
user specified conditions.
The breakpoint setting code is changed to allow overlapping one
internal breakpoint on a user breakpoint, or a user breakpoint on an
existing internal breakpoint. All other combinations are rejected. The
breakpoint clearing code is changed to clear the UserBreakpoint bit and
only remove the phisical breakpoint if no other bits are set in the
Kind field. ClearInternalBreakpoints does the same thing but clearing
all bits that aren't the UserBreakpoint bit.
Fixes#844
Move some duplicate code, related to breakpoints, that was in both
backends into a single place.
This is in preparation to solve issue #844 (conditional breakpoints
make step and next fail) which will make this common breakpoint code
more complicated.
Instead of only tracking a few cherrypicked registers in stack.go track
all DWARF registers.
This is needed for cgo code and for the locationlists emitted by go in
1.10:
* The debug_frame sections emitted by C compilers can not be used
without tracking all registers
* the loclists emitted by go1.10 need all registers of a frame to be
interpreted.
gosymtab and gopclntab only contain informations about go code, linked
C code isn't there, we should use debug_line instead to also cover C.
Updates #935
* string to []rune
* string to []byte
* []rune to string
* []byte to string
* any pointer to uintptr
The string, []rune, []byte conversion pairs aligns this to the go
language.
The pointer -> uintptr conversion pair is symmetric to the uintptr ->
pointer that we already have.
Also lets the user specify any size for byte array types instead of
just the ones already used by the program, this can be used to read
arbitrary memory.
Fixes#548, #867
debugserver doesn't support qXfer:exec-file:read, and it doesn't return
the executable path in the response to qProcessInfoPID, however we can
find out the executable path by using jGetLoadedDynamicLibrariesInfos.
Before go1.9 embedded struct fields had name == "" in runtime and ==
type name in DWARF. After go1.9 both runtime and DWARF use a simplified
version of the type as name.
Embedded structs are distinguished from normal fields by setting a flag
in the runtime.structfield, for runtime, and by adding a custom
attribute in DWARF.
Splits out type parsing and go-specific Type hierarchy from
x/debug/dwarf, replace x/debug/dwarf with debug/dwarf everywhere,
remove x/debug/dwarf from vendoring.
Instead of panicing for sending on a closed channel, detect that the
process has exited and return a proper error message.
This patch also cleans up some spots where the Pid is omitted from the
error.
Fixes#920
If the user tries to list the contents of a function pointer but
forgets the '*' operator the location lookup will fail and result in a
unhelpful "location not found" error.
Instead if the location lookup fails we should try interpreting the
locspec as if it was preceded by '*'.
When the process exits during we used to return an error, but after
commit 8bbcc89711f4263e7bb2b6d9c00fa96d0294e56f we move the error into
state.Err. Revert this behavior change.
If one of the expressions that are automatically evaluated when a
breakpoint is hit can't be evaluated breakpoint information collection
should continue and the error should be returned for that specific
expression instead of the whole command.
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
When location spec is given and the base can be interpreted either in
source file name or function name, NomalLocationSpec searches both
the source file list and the function symbol list, and selects matching
candidates. Previously, all the matching candidates were added to one
single list regardless whether the candidate was from the source file
list or not. Then, later, Find tries to guess whether the candiate
was a function or a file based on a heuristic, i.e, whether the
candidate is an absolute file path. The heuristic is fragile - since
there is no guarantee that the included source file name is an absolute
path.
Instead, this CL preserves where the candidate was found; file list or
function symbol list. Then, use that info to determine whether the
candidate is a source file name or not.
The concrete value of an interface is always stored as a pointer inside
an interface variable. So far we have followed the memory layout and
reported the type of the 'data' attribute of interfaces as a pointer,
however this makes it impossible to distinguish interfaces with
concrete value of type 'A' from interfaces of concrete value of type
'*A'.
With this changeset when we autodereference pointers when the concrete
type of an interface is not a pointer.
* Fix various issues detected by megacheck
I've ran honnef.co/go/tools/cmd/megacheck and fixed a few of the
things that came up there.
* Cleanup using Gogland
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.
A next/step/stepout command could hit a normal breakpoint, decorated
with a list of variables to evaluate, if that happens the variable
should be evaluated just as if the breakpoint was hit by a continue.
Implementing proc.Process.Running in a thread safe way is complicated
and nothing actually uses it besides tests, so we are better off
rewriting the tests without Running and removing it.
In particular:
* The call to d.target.Running() in service/debugger/debugger.go
(Restart) can never return true because that line executes while
holding processMutex and all continue operations are also executed
while holding processMutex.
* The call to dbp.Running() pkg/proc/native/proc.go (Detach) can never
return true, because it's only called from
debugger.(*Debugger).detach() which is also always called while
holding processMutex.
Since some tests are hard to write correctly without Process.Running a
simpler interface, Process.NotifyResumed, is introduced.
Fixes#830
- moved target.Interface into proc as proc.Process
- rename proc.IThread to proc.Thread
- replaced interfaces DisassembleInfo, Continuable and
EvalScopeConvertible with Process.
- removed superfluous Gdbserver prefix from types in the gdbserial
backend.
- removed superfluous Core prefix from types in the core backend.
According to https://golang.org/cmd/go/#hdr-Test_packages
service_test is more appropriate becuase this directory contains
no non-test code and the intention is to compile these *_test.go
files as a separate package and link/run with the main test package.
* proc: Refactor stackIterator to use memoryReadWriter and BinaryInfo
* proc: refactor EvalScope to use memoryReadWriter and BinaryInfo
* proc: refactor Disassemble to use memoryReadWriter and BinaryInfo
* proc: refactor BinaryInfo part of proc.Process to own type
The data structures and associated code used by proc.Process
to implement target.BinaryInfo will also be useful to support a
backend for examining core dumps, split this part of proc.Process
to a different type.
* proc: compile support for all executable formats unconditionally
So far we only compiled in support for loading the executable format
supported by the host operating system.
Once support for core files is introduced it is however useful to
support loading in all executable formats, there is no reason why it
shouldn't be possible to examine a linux coredump on windows, or
viceversa.
* proc: bugfix: do not resume threads on detach if killing
* Replace BinaryInfo interface with BinInfo() method returning proc.BinaryInfo
On Windows we can sometimes encounter threads stopped in locations for
which we do not have entries in debug_frame.
These cases seem to be due to calls to Windows API in the go runtime,
we can still produce a (partial) stack trace in this circumstance by
following frame pointers (starting with BP).
We still prefer debug_frame entries when available since go functions
do not have frame pointers before go1.8.
* service/rpccommon: fixed typo
* proc: test parseG while target is in runtime.deferreturn
runtime.deferreturn will change the value of curg._defer.fn in such a
way that if the target is stopped at just the right instruction it
may crash an incorrect implementation of parseG
* proc/stack: handle stack barriers correctly
Correctly handle stack barriers insterted during garbage collection.
We are already doing this in GoroutinesInfo we should be doing it for
GetG. The main consequence of not doing this is that the CurrentLoc of
DebuggerState.SelectedGoroutine is out of date compared to the location
of the thread running it.
* dwarf/line: bugfix: not all values of the state machine can be used
According to DWARF Version 3 Section 6.2 "Line Number Information" not
all the values transversed by the line numbers state machine are valid
instructions, only the ones after a "special opcode", after the
standard opcode DW_LNS_copy and the extended opcode
DW_LINE_end_sequence.
DWARF3 describes this by specifying that only the opcodes listed above
"append a row to the matrix".
Additionally the implementation of DW_LNS_const_add_pc was wrong.
Fixes#664
* dwarf/line: fixed test failing with go1.8
* service/test: fix prologue detection tests
The conditions about which function prologue is emitted by the compiler
changed in go1.8, changed the test program so that callme2 will still
have a prologue under go1.8.
* service/test: fix step test
compilation units are linked in a different order under go1.8 so the
code of 'fmt' is no longer located after 'main' in the executable,
changed the tests so that they don't rely on this assumption anymore.
* proc: change runtime.Breakpoint support for go1.8
Before 1.8 it was sufficient to step twice to exit a
runtime.Breakpoint(), but go 1.8 added frame pointer tracking to small
functions making runtime.Breakpoint longer.
This changes runtime.Breakpoint handling in Continue to single step as
many times as are needed to exit runtime.Breakpoint.
* proc/test: fix TestIssue561 for go1.8
* service: Prevent panics from crashing delve and killing the target
Catch all unrecovered proc and debugger panics in the service layer and
report them as errors, allow users to cleanly detach from the target
and quit.
Fixes#614
* proc: Next/Step should not panic if line info can not be found.
Fixes#683
* 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
* proc: Add `wd` to Launch
This change adds the `wd` arg which specify working directory of the
program.
Fixes#295
* service/debugger: Add `Wd` field to debugger.Config
This change adds the `Wd` field which specify working directory of the
program launched by debugger.
Fixes#295
* service: Add `Wd` to service.Config
This change adds the `Wd` field which specify working directory of the
program debugger will launch.
Fixes#295
* cmd/dlv: Add `Wd` flag
This change adds `Wd` flag which specify working directory of the
program which launched by debugger.
Fixes#295
* only set the Linux working directory if it is set,
stub out param in darwin and windows
* set working directory for Windows
https://godoc.org/golang.org/x/sys/windows#CreateProcesshttps://msdn.microsoft.com/en-us/library/windows/desktop/ms682425(v=vs.85).aspx
* Windows workingDir must be an *uint16
* attempt to chdir on darwin via @yuntan
* proc/exec_darwin.c: fix working directory for darwin
* Add tests to check if working directory works.
* Fix darwin implementation of fork/exec, which paniced if
child fork returned.
* cmd, service: rename Wd to WorkingDir
