Commit Graph

229 Commits

Author SHA1 Message Date
aarzilli
85e4ba439c proc/core: add support for windows minidumps
Minidumps are the windows equivalent of unix core files.
This commit updates pkg/proc/core so that it can open and read windows
minidumps.

Updates #794
2018-11-21 12:17:16 -08:00
aarzilli
31fff84519 proc: move windows register handling code to winutil package
Move windows register handling code to winutil package in preparation
for using it in proc/core to read minidump files.
2018-11-21 12:17:16 -08:00
aarzilli
3048b9605a proc: correctly extract name of functions that have been inlined
If a function can be inlined it will appear as two entries in
debug_info. A DW_TAG_subprogram entry with DW_AT_inlined = true (that
will be used as the abstract origin) and a second DW_TAG_subprogram
entry with an abstract origin.
To retrieve the name of this second entry we must load its abstract
origin.
2018-11-20 12:57:25 -08:00
aarzilli
b8ed126bf6 proc/*: allow stepping into functions without debug_info symbols
If proc.Step encounters a CALL instruction that points to an address
that isn't associated with any function it should still follow the
CALL.

The circumstances creating this problem do not normally occur, it was
encountered in the process of fixing a bug created by Go1.12.
2018-11-20 12:57:25 -08:00
aarzilli
f8c0c37f30 proc: remove inversion of return variables from returnBreakpointInfo
It was never true that return variables were in the inverse order.
Instead in Go1.11 return variables are saved in debug_info in an
arbitrary order and inverting them just happened to work for this
specific example.

This bug was fixed in Go 1.12, regardless we should attempt to
rearrange return variables anyway.
2018-11-20 12:57:25 -08:00
aarzilli
7f53117ea9 proc: do not panic if we can't satisfy a composite location
When a location expression requests a register check that we have as
many bytes in the register as requested and if we don't report the
error.

Updates #1416
2018-11-19 14:46:35 -08:00
Sergio Lopez
11accd4d71 proc/proc: Extend GoroutinesInfo to allow specifying a range
Instead of unconditionally returning all present goroutines,
GoroutinesInfo now allows specifying a range (start and count). In
addition to the array of goroutines and the error, it now also returns
the next goroutine to be processed, to be used as 'start' argument on
the next call, or 0 if all present goroutines have already been
processed.

This way clients can avoid eating large amounts of RAM while debugging
core dumps and processes with a exceptionally high amount of goroutines.

Fixes #1403
2018-11-19 10:06:38 -08:00
Derek Parker
3cfb00b2cc pkg/proc: Cleanup duplicated panic breakpoint code 2018-11-15 18:16:16 +01:00
Derek Parker
d61cd1c0d7 pkg/proc: Refactor process post initialization
This patch is a slight refactor to share more code used for genericprocess initialization. There will always be OS/backend specificinitialization, but as much as can be shared should be to preventduplicating of any logic (setting internal breakpoints, loading bininfo,etc).
2018-11-15 18:16:16 +01:00
aarzilli
89c8da65b6 proc: Improve performance of loadMap on very large sparse maps
Users can create sparse maps in two ways, either by:
a) adding lots of entries to a map and then deleting most of them, or
b) using the make(mapType, N) expression with a very large N

When this happens reading the resulting map will be very slow
because loadMap needs to scan many buckets for each entry it finds.

Technically this is not a bug, the user just created a map that's
very sparse and therefore very slow to read. However it's very
annoying to have the debugger hang for several seconds when trying
to read the local variables just because one of them (which you
might not even be interested into) happens to be a very sparse map.

There is an easy mitigation to this problem: not reading any
additional buckets once we know that we have already read all
entries of the map, or as many entries as we need to fulfill the
MaxArrayValues parameter.

Unfortunately this is mostly useless, a VLSM (Very Large Sparse Map)
with a single entry will still be slow to access, because the single
entry in the map could easily end up in the last bucket.

The obvious solution to this problem is to set a limit to the
number of buckets we read when loading a map. However there is no
good way to set this limit.
If we hardcode it there will be no way to print maps that are beyond
whatever limit we pick.
We could let users (or clients) specify it but the meaning of such
knob would be arcane and they would have no way of picking a good
value (because there is no objectively good value for it).

The solution used in this commit is to set an arbirtray limit on
the number of buckets we read but only when loadMap is invoked
through API calls ListLocalVars and ListFunctionArgs. In this way
`ListLocalVars` and `ListFunctionArgs` (which are often invoked
automatically by GUI clients) remain fast even in presence of a
VLSM, but the contents of the VLSM can still be inspected using
`EvalVariable`.
2018-11-09 08:12:45 -08:00
Derek Parker
51c342c6b7 pkg/prog: Improve support for external debug info
Adds a config file option to allow specifying a list of directories to
search in when looking for seperate external debug info files.

Fixes #1353
2018-11-08 10:16:42 -08:00
Derek Parker
a2346ef69a pkg/proc: Unexport exported members of unexported type 2018-11-08 10:16:42 -08:00
Derek Parker
7a414662c0 pkg/proc: Reorganize struct members 2018-11-08 10:16:42 -08:00
aarzilli
7d0d2cb3e6 pkg/core: make code in core.go OS/arch agnostic
Make code in core.go OS and architecture agnostic in preparation for
adding Windows minidump support.
2018-11-06 11:20:38 -08:00
aarzilli
ea3428550d proc/native,proc/core: deduplicate linux register handling code
The linux version of proc/native and proc/core contained largely
overlapping implementations of the register handling code, deduplicate
it by moving it into proc/linutil.
2018-10-22 12:19:09 -07:00
Derek Parker
3129aa7330 *: Show return values on CLI trace
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
2018-10-19 20:32:27 +02:00
aarzilli
4db9939845 proc/native: Mask MS_VC_EXCEPTION [windows]
Some libraries (for example steam_api64.dll) will send this exception
code to set the thread name on Microsoft VisualC.
In theory it should be fine to send the exception back to the target,
which is responsible for setting a handler for it, in practice in some
cases (steam_api64.dll) this will crash the program. So we'll mask it
instead.

Fixes #1383
2018-10-19 10:33:40 -07:00
aarzilli
b5cf584564 proc/gdbserial: backward continue should stop at start of process
ContinueOnce didn't detect the way RR signals that it has reached the
start of the process and would never finish.

Fixes #1376
2018-10-17 09:07:36 -07:00
aarzilli
f72c48c034 proc: Continue should always work after CallFunction
Continue did not resume execution after a call to CallFunction if the
point where the process was stopped, before the call CallFunction, was
a breakpoint.

Fixes #1374
2018-10-17 09:07:36 -07:00
aarzilli
b59032516e proc,service,terminal: eval expressions in the scope of a deferred call
Add ability to evaluate variables on the scope of a deferred call's
argument frame.
2018-10-16 08:40:07 -07:00
aarzilli
d2904322fa proc: add flag to disable escape checking in function calls
Fix escape checking in function calls  and add a flag to disable it.
2018-10-15 09:31:35 -07:00
chainhelen
143cf6aebf pkg/proc: extend conversion about string for array/str
Extend `string()`
1.convert `byte/rune array`(not only `slice`) to string.
2.convert string to string(itself), just like `string(str)` in go language.
2018-10-15 09:27:39 -07:00
aarzilli
74c98bc961 proc: support position independent executables (PIE)
Support for position independent executables (PIE) on the native linux
backend, the gdbserver backend on linux and the core backend.
Also implemented in the windows native backend, but it can't be tested
because go doesn't support PIE on windows yet.
2018-10-11 11:21:27 -07:00
aarzilli
910f90c3c8 proc/native,Makefile: allow compiling on macOS without native backend
On macOS 10.14 Apple changed the command line tools so that system
headers now need to be manually installed.

Instead of adding one extra install step to the install procedure add a
build tag to allow compilation of delve without the native backend on
macOS. By default (i.e. when using `go get`) this is how delve will be
compiled on macOS, the make script is changed to enable compiling the
native backend if the required dependencies have been installed.

Insure that both configuration still build correctly on Travis CI and
change the documentation to describe how to compile the native backend
and that it isn't normally needed.

Fixes #1359
2018-10-02 10:46:09 -07:00
aarzilli
79a0e216ab proc: add iface.(data) syntax to access concrete value of an interface
With this syntax users do not need to type the concrete type of an
interface variable to access its contents. This also sidesteps the
problem where the serialization of a type by go/printer is different
from the one used for debug_info type names.

Updates #1328
2018-09-27 14:09:26 -07:00
chainhelen
1b4c318376 pkg/proc: use method not duplicate code
Use IsInternal and IsUser of Breakpoint, not duplicate code
2018-09-26 08:33:02 -07:00
aarzilli
50419b61da proc: implement conversion of integers to string
Go allows converting a single integer value to string, resulting in a
string containing a single unicode rune with the same code as the value
of the integer.
Allow the same conversion to happen.

Fixes #1322
2018-09-25 09:52:04 -07:00
aarzilli
a2eb983e3c proc: be more lenient with errors in GoroutinesInfo
Instead of failing on the first goroutine we can't read save the error
message and keep going.

Fixes a bug reported on the mailing list:
https://groups.google.com/d/msgid/delve-dev/3b3bfaa3-83d5-4676-b974-1fec40e5bf53%40googlegroups.com?utm_medium=email&utm_source=footer
2018-09-25 08:44:13 -07:00
chainhelen
ed9d231a6f pkg/proc/core: add an new error named ErrChangeRegisterCore
This commit just add an new error when trying to change register
values for core files (output the same infomation).
2018-09-24 10:25:46 -07:00
Derek Parker
c3f50742b9 *: Misc refactors, and doc additions
Refactors some code, adds a bunch of docstrings and just generally fixes
a bunch of linter complaints.
2018-09-19 20:59:35 +02:00
aarzilli
ac74944d53 proc,service,terminal: information about stack trace truncation
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.
2018-08-30 16:52:00 -07:00
aarzilli
b8e80746e5 proc/native: implement Copy/RestoreRegisters on windows 2018-08-30 15:48:10 -07:00
aarzilli
438e51f330 proc: replace SavedRegisters interface with a Copy method
Fncall.go was written with the assumption that the object returned by
proc.Thread.Registers does not change after we call
proc.Thread.SetPC/etc.

This is true for the native backend but not for gdbserial. I had
anticipated this problem and introduced the Save/SavedRegisters
mechanism during the first implementation of fncall.go but that's
insufficient.

Instead:

1. clarify that the object returned by proc.Thread.Registers could
   change when the CPU registers are modified.
2. add a Copy method to Registers that returns a copy of the registers
   that are guaranteed not to change when the CPU registers change.
3. remove the Save/SavedRegisters mechanism.

This solution leaves us the option, in the future, to cache the output
of proc.(Thread).Registers, avoiding a system call every time it's
called.
2018-08-30 15:48:10 -07:00
Derek Parker
f1e66f075f Add function call support for OSX
Implements missing functionality in gdbserial to enable function calls
on OSX.
2018-08-30 15:48:10 -07:00
aarzilli
0461af8392 proc: fix type of some struct global variables
Normally variables that have a named struct as a type will get a
typedef entry as their type, sometimes however the Go linker will
decide to use the DW_TAG_structure_type entry instead.

For consistency always wrap a struct type into a typedef when we are
creating a new variables (see comment in newVariable for exceptions).

This fixes a bug where it would be impossible to call methods on a
global variable.
2018-08-29 16:16:20 -07:00
aarzilli
cab09a4bbb proc: fix next when disassembly fails
Next should work even if one or more instructions in the current
function can not be disassembled.
2018-08-29 16:11:18 -07:00
aarzilli
19ba86c0c9 proc: support calls through function pointers 2018-08-16 12:44:02 -07:00
aarzilli
7c42fc51d7 proc: support calls to methods directly and through interface 2018-08-16 12:44:02 -07:00
aarzilli
51994aafd3 proc: evaluate var.method expressions
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.
2018-08-16 12:44:02 -07:00
aarzilli
9335c54014 proc: use (*Variable).setValue in fncall 2018-08-15 10:29:16 -07:00
aarzilli
12a3f8bb97 proc: change (*Variable).setValue for use in CallFunction
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.
2018-08-15 10:29:16 -07:00
Derek Parker
49bfbe6d24 proc: Increase inline function support
This patch makes it so inlined functions are returned in the
function
list, and also allows users to set breakpoints on the call site of
inlined functions.

Fixes #1261
2018-08-08 11:08:34 +02:00
aarzilli
568251e43f proc_test: fix test failure on macOS
Something changed on Travis side that broke TestIssue877. Disable that
test when $TRAVIS is set to true.
2018-08-07 17:57:22 -07:00
aarzilli
7e15327e84 proc/native,proc/gdbserial: ignore SIGTTIN, SIGTTOU when fg'ing target
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
2018-07-31 12:05:54 -07:00
aarzilli
8f1fc63da8 proc,service,terminal: read defer list
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.
2018-07-24 14:58:56 -07:00
aarzilli
368cbeb0bc dwarf/line: remove foundFile "optimization" from LineToPC
There is no guarantee that files will end up stored contiguously in the
debug_line section which makes this optimization wrong in the general
case.
In particular with recent versions of go1.11 and a go.mod file present
the go compiler seems to sometimes produce executables that actually
violate this assumption.
2018-07-23 10:08:28 -07:00
aarzilli
86120a3b40 proc/gdbserial: do not run rr when perf_event_paranoid > 1
On newer kernels when /proc/sys/kernel/perf_event_paranoid is > 1 rr
will crash with SIGABRT. Return an error instead of letting this
happen.
2018-07-19 15:25:22 -07:00
aarzilli
2925c0310a *: function call injection for go 1.11
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
2018-07-13 13:37:54 -07:00
aarzilli
0c15ca5f19 proc: allow breakpoint conditions to contain a single boolean variable
Fixes a bug where breakpoint condition evaluation would never load the
value if the breakpoint condition consisted of just a single variable.

Fix #1264
2018-07-09 17:25:47 -07:00
aarzilli
2309f728c1 proc,service,terminal: propagate g.startpc
Adds StartPC to proc.G, StartLoc to api.Goroutine and show the start
location in the command line client when appropriate.

Updates #1104
2018-07-09 17:20:55 -07:00