qEcho:%s
where '%s' is any valid string. The response to this packet is the exact packet itself with no changes, just reply with what you received!
This will help us to recover from packets timing out much more gracefully. Currently if a packet times out, LLDB quickly will hose up the debug session. For example, if we send a "abc" packet and we expect "ABC" back in response, but the "abc" command takes longer than the current timeout value this will happen:
--> "abc"
<-- <<<error: timeout>>>
Now we want to send "def" and get "DEF" back:
--> "def"
<-- "ABC"
We got the wrong response for the "def" packet because we didn't sync up with the server to clear any current responses from previously issues commands.
The fix is to modify GDBRemoteCommunication::WaitForPacketWithTimeoutMicroSecondsNoLock() so that when it gets a timeout, it syncs itself up with the client by sending a "qEcho:%u" where %u is an increasing integer, one for each time we timeout. We then wait for 3 timeout periods to sync back up. So the above "abc" session would look like:
--> "abc"
<-- <<<error: timeout>>> 1 second
--> "qEcho:1"
<-- <<<error: timeout>>> 1 second
<-- <<<error: timeout>>> 1 second
<-- "abc"
<-- "qEcho:1"
The first timeout is from trying to get the response, then we know we timed out and we send the "qEcho:1" packet and wait for 3 timeout periods to get back in sync knowing that we might actually get the response for the "abc" packet in the mean time...
In this case we would actually succeed in getting the response for "abc". But lets say the remote GDB server is deadlocked and will never response, it would look like:
--> "abc"
<-- <<<error: timeout>>> 1 second
--> "qEcho:1"
<-- <<<error: timeout>>> 1 second
<-- <<<error: timeout>>> 1 second
<-- <<<error: timeout>>> 1 second
We then disconnect and say we lost connection.
We might also have a bad GDB server that just dropped the "abc" packet on the floor. We can still recover in this case and it would look like:
--> "abc"
<-- <<<error: timeout>>> 1 second
--> "qEcho:1"
<-- "qEcho:1"
Then we know our remote GDB server is still alive and well, and it just dropped the "abc" response on the floor and we can continue to debug.
<rdar://problem/21082939>
llvm-svn: 238530
In ProcessGDBRemote we currently have a single packet, m_last_stop_packet, used to set the thread stop info.
However in non-stop mode we can receive several stop reply packets in a sequence for different threads. As a result we need to use a container to hold them before they are processed.
This patch also changes the return type of CheckPacket() so we can detect async notification packets.
Reviewers: clayborg
Subscribers: labath, ted, deepak2427, lldb-commits
Differential Revision: http://reviews.llvm.org/D9853
llvm-svn: 238323
Summary:
This patch is the beginnings of support for Non-stop mode in the remote protocol. Letting a user examine stopped threads, while other threads execute freely.
Non-stop mode is enabled using the setting target.non-stop-mode, which sends a QNonStop packet when establishing the remote connection.
Changes are also made to treat the '?' stop reply packet differently in non-stop mode, according to spec https://sourceware.org/gdb/current/onlinedocs/gdb/Remote-Non_002dStop.html#Remote-Non_002dStop.
A setting for querying the remote for default thread on setup is also included.
Handling of '%' async notification packets will be added next.
Reviewers: clayborg
Subscribers: lldb-commits, ADodds, ted, deepak2427
Differential Revision: http://reviews.llvm.org/D9656
llvm-svn: 237239
Removed some unused variables, added some consts, changed some casts
to const_cast. I don't think any of these changes are very
controversial.
Differential Revision: http://reviews.llvm.org/D9674
llvm-svn: 237218
Summary:
New dotest options that allow arbitrary log channels and
categories to be enabled. Also enables logging for locally run
debug servers.
Log messages are separated into separate files per test case.
(this makes it possible to log in dosep runs)
These new log files are stored side-by-side with trace files in the
session directory.
These files are deleted by default if the test run is successful.
If --log-success is specified, even successful logs are retained.
--log-success is useful for creating reference log files.
Test Plan:
add '--channel "lldb all" --channel "gdb-remote packets" --log-success'
to your dotest options
Tested on OSX and Linux
Differential Revision: http://reviews.llvm.org/D9594
llvm-svn: 236956
Summary:
Currently, launching lldb-gdbserver from platform on Android requires root for
mkfifo() and an explicit TMPDIR variable. This should remove both requirements.
Test Plan: Successfully launched lldb-gdbserver on a non-rooted Android device.
Reviewers: tberghammer, vharron, clayborg
Reviewed By: clayborg
Subscribers: tberghammer, lldb-commits
Differential Revision: http://reviews.llvm.org/D9307
llvm-svn: 235940
This new class makes it easier to change the timeout of a
GDBRemoteCommunication instance for a short time and then restore it to
its original value.
Differential revision: http://reviews.llvm.org/D7826
llvm-svn: 230319
This commit merges lldb-platform and lldb-gdbserver into a single binary
of the same size as each of the previous individual binaries. Execution
mode is controlled by the first argument being either platform or
gdbserver.
Patch from: flackr <flackr@google.com>
Differential revision: http://reviews.llvm.org/D7545
llvm-svn: 229683
The refactor was motivated by some comments that Greg made
http://reviews.llvm.org/D6918
and also to break a dependency cascade that caused functions linking
in string->int conversion functions to pull in most of lldb
llvm-svn: 226199
This reverts commit 4a5ad2c077166cc3d6e7ab4cc6e3dcbbe922af86.
Windows doesn't support select() for pipe objects, and this also fails
to compile on Windows. Reverting this until we can get it sorted out
to keep the windows build working.
llvm-svn: 223392
The details are: large packets (like large memory reads (m packets) or large binary memory reads (x packet)) can get responses that come in across multiple read() calls. The while loop that was added meant that if only a partial packet came in (like only "$abc" coming for a response) GDBRemoteCommunication::CheckForPacket() was called, it would deadlock in the while loop because no more data is going to come in as this function needs to be called again with more data from another read. So the original fix will need to be corrected and resubmitted.
<rdar://problem/18853744>
llvm-svn: 221181
As part of getting ConnectionFileDescriptor working on Windows,
there is going to be alot of platform specific work to be done.
As a result, the implementation is moving into Host. This patch
performs the code move and fixes up call-sites appropriately.
Reviewed by: Greg Clayton
Differential Revision: http://reviews.llvm.org/D5548
llvm-svn: 219143
This patch moves creates a thread abstraction that represents a
thread running inside the LLDB process. This is a replacement for
otherwise using lldb::thread_t, and provides a platform agnostic
interface to managing these threads.
Differential Revision: http://reviews.llvm.org/D5198
Reviewed by: Jim Ingham
llvm-svn: 217460
This patch accepts environment variables of the form:
LLDB_DEBUGSERVER_EXTRA_ARG_n
where n starts with 1, and may continue nearly indefinitely (up through std::numeric_limits<uint32_t>::max()).
The code loops around, starting with 1, until it doesn't find one of the environment variables. For each one it does find defined, it appends the environment variable's contents to the end of the debugserver/llgs startup command line issued when the stub is started for local debugging.
I am using this to add arbitrary startup commands to the llgs command line for turning on additional logging. For example:
export LLDB_DEBUGSERVER_EXTRA_ARG_1="-c"
export LLDB_DEBUGSERVER_EXTRA_ARG_2="log enable -f /tmp/llgs_packets.log gdb-remote packets"
export LLDB_DEBUGSERVER_EXTRA_ARG_3="-c"
export LLDB_DEBUGSERVER_EXTRA_ARG_4="log enable -f /tmp/llgs_process.log lldb process"
llvm-svn: 216745
This continues the effort to get Host code moved over to HostInfo,
and removes many more instances of preprocessor defines along the
way.
llvm-svn: 216195
More specifically, this change can be summarized as follows:
1) Makes an lldbHostPosix library which contains code common to
all posix platforms.
2) Creates Host/FileSystem.h which defines a common FileSystem
interface.
3) Implements FileSystem.h in Host/windows and Host/posix.
4) Creates Host/FileCache.h, implemented in Host/common, which
defines a class useful for storing handles to open files needed
by the debugger.
Differential Revision: http://reviews.llvm.org/D4889
llvm-svn: 215775
This patch moves the logic of many common socket operations into
its own class lldb_private::Socket. It then modifies the
ConnectionFileDescriptor class, and a few users of that class,
to use this new Socket class instead of hardcoding socket logic
directly.
Finally, this patch creates a common interface called IOObject for
any objects that support reading and writing, so that endpoints
such as sockets and files can be treated the same.
Differential Revision: http://reviews.llvm.org/D4641
Reviewed by: Todd Fiala, Greg Clayton
llvm-svn: 214984
This change enables lldb-platform for Linux. In addition, it does the following:
* fixes Host::GetLLDBPath() to work on Linux/*BSD for ePathTypeSupportExecutableDir-relative paths.
* adds more logging and comments around lldb-platform startup and remote lldb-platform usage.
* refactors lldb-platform remote-* support for Darwin and Linux into PlatformPOSIX. This, in theory, is the bulk of what is needed for *BSD to make remote connections to lldb-platform as well (although I haven't tested that yet). FreeBSD can make similar changes to their Platform* as was made here for PlatformLinux to pick up the rest of the bits.
* teaches GDBRemoteCommunication to use lldb-gdbserver for non-Apple hosts.
llvm-svn: 213707
- CTRL+C wasn't clearing the command in lldb
- CTRL+C doesn't work in python macros in lldb
- Ctrl+C no longer interrupts the running process that you attach to
<rdar://problem/15949205>
<rdar://problem/16778652>
<rdar://problem/16774411>
llvm-svn: 207816
right after the space for it is allocated on the stack, instead of trying
to initialize it in all the different places in this method. It's too easy
for another uninitialized code path to sneak in as it is written right now.
llvm-svn: 200066
<rdar://problem/15600045>
Due to other recent changes, all connections to GDB servers that didn't support the "QStartNoAckMode" packet would cause us to fail to attach to the remote GDB server.
The problem was that SendPacket* and WaitForResponse* packets would return a size_t indicating the number of bytes sent/received. The other issue was WaitForResponse* packets would strip the leading '$' and the trailing "#CC" (checksum) bytes, so the unimplemented response packet of "$#00" would get stripped and the WaitForResponse* packets would return 0.
These new error codes give us flexibility to to more intelligent things in response to what is returned.
llvm-svn: 196610
This gets rid of our hacky "get_random_port()" which would grab a random port and tell debugserver to open that port. Now LLDB creates, binds, listens and accepts a connection by binding to port zero and sending the correctly bound port down as the host:port to connect back to.
Fixed the "ConnectionFileDescriptor" to be able to correctly listen for connections from a specified host, localhost, or any host. Prior to this fix "listen://" only accepted the following format:
listen://<port>
But now it can accept:
listen://<port> // Listen for connection from localhost on port <port>
listen://<host>:<port> // Listen for connection from <host> and <port>
listen://*:<port> // Listen for connection from any host on port <port>
llvm-svn: 196547
This helps ensure that the launched debugserver is ready and listening for a connection. Prior to this we had a race condition.
Consolidate the launching of debugserver into a single place: a static function in GDBRemoteCommunication.
llvm-svn: 196401
