This reverts commit 913457acf0.
It again broke builds on Windows:
lldb/source/Host/common/HostNativeThreadBase.cpp(37,14): error:
assigning to 'lldb::thread_result_t' (aka 'unsigned int') from
incompatible type 'std::nullptr_t'
This is a re-submission of 24d2405588
without the hunk in HostNativeThreadBase.h, which breaks builds on
Windows.
Identified with modernize-use-nullptr.
This reverts commit 24d2405588.
Breaks building on Windows:
../../lldb/include\lldb/Host/HostNativeThreadBase.h(49,36): error:
cannot initialize a member subobject of type 'lldb::thread_result_t'
(aka 'unsigned int') with an rvalue of type 'std::nullptr_t'
lldb::thread_result_t m_result = nullptr;
^~~~~~~
1 error generated.
Multithreaded applications using fork(2) need to be extra careful about
what they do in the fork child. Without any special precautions (which
only really work if you can fully control all threads) they can only
safely call async-signal-safe functions. This is because the forked
child will contain snapshot of the parents memory at a random moment in
the execution of all of the non-forking threads (this is where the
similarity with signals comes in).
For example, the other threads could have been holding locks that can
now never be released in the child process and any attempt to obtain
them would block. This is what sometimes happen when using tcmalloc --
our fork child ends up hanging in the memory allocation routine. It is
also what happened with our logging code, which is why we added a
pthread_atfork hackaround.
This patch implements a proper fix to the problem, by which is to make
the child code async-signal-safe. The ProcessLaunchInfo structure is
transformed into a simpler ForkLaunchInfo representation, one which can
be read without allocating memory and invoking complex library
functions.
Strictly speaking this implementation is not async-signal-safe, as it
still invokes library functions outside of the posix-blessed set of
entry points. Strictly adhering to the spec would mean reimplementing a
lot of the functionality in pure C, so instead I rely on the fact that
any reasonable implementation of some functions (e.g.,
basic_string::c_str()) will not start allocating memory or doing other
unsafe things.
The new child code does not call into our logging infrastructure, which
enables us to remove the pthread_atfork call from there.
Differential Revision: https://reviews.llvm.org/D116165
This is an updated version of the https://reviews.llvm.org/D113789 patch with the following changes:
- We no longer modify modification times of the cache files
- Use LLVM caching and cache pruning instead of making a new cache mechanism (See DataFileCache.h/.cpp)
- Add signature to start of each file since we are not using modification times so we can tell when caches are stale and remove and re-create the cache file as files are changed
- Add settings to control the cache size, disk percentage and expiration in days to keep cache size under control
This patch enables symbol tables to be cached in the LLDB index cache directory. All cache files are in a single directory and the files use unique names to ensure that files from the same path will re-use the same file as files get modified. This means as files change, their cache files will be deleted and updated. The modification time of each of the cache files is not modified so that access based pruning of the cache can be implemented.
The symbol table cache files start with a signature that uniquely identifies a file on disk and contains one or more of the following items:
- object file UUID if available
- object file mod time if available
- object name for BSD archive .o files that are in .a files if available
If none of these signature items are available, then the file will not be cached. This keeps temporary object files from expressions from being cached.
When the cache files are loaded on subsequent debug sessions, the signature is compare and if the file has been modified (uuid changes, mod time changes, or object file mod time changes) then the cache file is deleted and re-created.
Module caching must be enabled by the user before this can be used:
symbols.enable-lldb-index-cache (boolean) = false
(lldb) settings set symbols.enable-lldb-index-cache true
There is also a setting that allows the user to specify a module cache directory that defaults to a directory that defaults to being next to the symbols.clang-modules-cache-path directory in a temp directory:
(lldb) settings show symbols.lldb-index-cache-path
/var/folders/9p/472sr0c55l9b20x2zg36b91h0000gn/C/lldb/IndexCache
If this setting is enabled, the finalized symbol tables will be serialized and saved to disc so they can be quickly loaded next time you debug.
Each module can cache one or more files in the index cache directory. The cache file names must be unique to a file on disk and its architecture and object name for .o files in BSD archives. This allows universal mach-o files to support caching multuple architectures in the same module cache directory. Making the file based on the this info allows this cache file to be deleted and replaced when the file gets updated on disk. This keeps the cache from growing over time during the compile/edit/debug cycle and prevents out of space issues.
If the cache is enabled, the symbol table will be loaded from the cache the next time you debug if the module has not changed.
The cache also has settings to control the size of the cache on disk. Each time LLDB starts up with the index cache enable, the cache will be pruned to ensure it stays within the user defined settings:
(lldb) settings set symbols.lldb-index-cache-expiration-days <days>
A value of zero will disable cache files from expiring when the cache is pruned. The default value is 7 currently.
(lldb) settings set symbols.lldb-index-cache-max-byte-size <size>
A value of zero will disable pruning based on a total byte size. The default value is zero currently.
(lldb) settings set symbols.lldb-index-cache-max-percent <percentage-of-disk-space>
A value of 100 will allow the disc to be filled to the max, a value of zero will disable percentage pruning. The default value is zero.
Reviewed By: labath, wallace
Differential Revision: https://reviews.llvm.org/D115324
Lldb uses a pty to read/write to the standard input and output of the
debugged process. For host processes this would be automatically set up
by Target::FinalizeFileActions. The Qemu platform is in a unique
position of not really being a host platform, but not being remote
either. It reports IsHost() = false, but it is sufficiently host-like
that we can use the usual pty mechanism.
This patch adds the necessary glue code to enable pty redirection. It
includes a small refactor of Target::FinalizeFileActions and
ProcessLaunchInfo::SetUpPtyRedirection to reduce the amount of
boilerplate that would need to be copied.
I will note that qemu is not able to separate output from the emulated
program from the output of the emulator itself, so the two will arrive
intertwined. Normally this should not be a problem since qemu should not
produce any output during regular operation, but some output can slip
through in case of errors. This situation should be pretty obvious (to a
human), and it is the best we can do anyway.
For testing purposes, and inspired by lldb-server tests, I have extended
the mock emulator with the ability "program" the behavior of the
"emulated" program via command-line arguments.
Differential Revision: https://reviews.llvm.org/D114796
Refactor ConnectionFileDescriptor to improve code reuse for different
types of sockets. Unify method naming.
While at it, remove some (now-)dead code from Socket.
Differential Revision: https://reviews.llvm.org/D112495
Refactor ConnectionFileDescriptor to improve code reuse for different
types of sockets. Unify method naming.
While at it, remove some (now-)dead code from Socket.
Differential Revision: https://reviews.llvm.org/D112495
Remove the port predicate from Socket and ConnectionFileDescriptor,
and move it to gdb-remote. It is specifically relevant to the threading
used inside gdb-remote and with the new port callback API, we can
reliably move it there. While at it, switch from the custom Predicate
to std::promise/std::future.
Differential Revision: https://reviews.llvm.org/D112357
Unify the listen and connect code inside lldb-server to use
ConnectionFileDescriptor uniformly rather than a mix of it and Acceptor.
This involves:
- adding a function to map legacy values of host:port parameter
(including legacy server URLs) into CFD-style URLs
- adding a callback to return "local socket id" (i.e. UNIX socket path
or TCP port number) between listen() and accept() calls in CFD
- adding a "unix-abstract-accept" scheme to CFD
As an additional advantage, this permits lldb-server to accept any URL
known to CFD including the new serial:// scheme. Effectively,
lldb-server can now listen on the serial port. Tests for connecting
over a pty are added to test that.
Differential Revision: https://reviews.llvm.org/D111964
Replace bool+by-ref argument with llvm::Optional, and move the common
implementation into HostInfoPOSIX. Based on my (simple) experiment,
the uname and the sysctl approach return the same value on MacOS, so
there's no need for a mac-specific implementation of this functionality.
Differential Revision: https://reviews.llvm.org/D112457
Disable non-blocking mode that's enabled only for file:// and serial://
protocols. All read operations should be going through the select(2)
in ConnectionFileDescriptor::BytesAvaliable, which effectively erases
(non-)blocking mode differences in reading. We do want to perform
writes in the blocking mode.
Differential Revision: https://reviews.llvm.org/D112442
Optimize the iterator comparison logic to compare Current.data()
pointers. Use std::tie for assignments from std::pair. Replace
the custom class with a function returning iterator_range.
Differential Revision: https://reviews.llvm.org/D110535
Add a new serial:// protocol along with SerialPort that provides a new
API to open serial ports. The URL consists of serial device path
followed by URL-style options, e.g.:
serial:///dev/ttyS0?baud=115200&parity=even
If no options are provided, the serial port is only set to raw mode
and the other attributes remain unchanged. Attributes provided via
options are modified to the specified values. Upon closing the serial
port, its original attributes are restored.
Differential Revision: https://reviews.llvm.org/D111355
Add setters for common teletype properties to the Terminal class:
- SetRaw() to enable common raw mode options
- SetBaudRate() to set the baud rate
- SetStopBits() to select the number of stop bits
- SetParity() to control parity bit in the output
- SetHardwareControlFlow() to enable or disable hardware control flow
(if supported)
Differential Revision: https://reviews.llvm.org/D111030
Combine m_read_sp and m_write_sp into a single m_io_sp. In all
currently existing code paths, they are pointing to the same object
anyway.
Differential Revision: https://reviews.llvm.org/D111396
Move the POSIX-specific fd:// and file:// scheme handling into
separate methods. Replace the custom GetURLAddress() matching with
splitting into scheme and path, and matching scheme via
llvm::StringSwitch. Use early returns.
Differential Revision: https://reviews.llvm.org/D111321
Replace separate read and write NativeFile instances with a single
instance shared for reading and writing. There is no clear indication
why two instances were used in the first place, and replacing them
with just one does not seem to cause any regressions in tests or manual
'process connect file://...'.
Differential Revision: https://reviews.llvm.org/D111314
.. and reduce the scope of others. They don't follow llvm coding
standards (which say they should be used only when the same effect
cannot be achieved with the static keyword), and they set a bad example.
Refactor TerminalState to make the code simpler. Move 'struct termios'
to a PImpl-style subclass. Add an RAII interface to automatically store
and restore the state.
Differential revision: https://reviews.llvm.org/D110721
Remove TerminalStateSwitcher class. It is not used anywhere and its API
is really weird. This is the first step towards cleaning up Terminal.h.
Differential Revision: https://reviews.llvm.org/D110693
Apparently macOS is padding the name result with several padding zeroes at
the end. Just strip them all to pretend it's a C-string.
Thanks to Pavel for suggesting this fix.
The StringConvert API is no longer used anywhere but in debugserver.
Since debugserver does not use LLVM API, we cannot replace it with
llvm::to_integer() and llvm::to_float() there. Let's just move
the sources into debugserver.
Differential Revision: https://reviews.llvm.org/D110478
Refactor the XML converting attribute and text getters to use LLVM API.
While at it, remove some redundant error and missing XML support
handling, as the called base functions do that anyway. Add tests
for these methods.
Note that this patch changes the getter behavior to be IMHO more
correct. In particular:
- negative and overflowing integers are now reported as failures to
convert, rather than being wrapped over or capped
- digits followed by text are now reported as failures to convert
to double, rather than their numeric part being converted
Differential Revision: https://reviews.llvm.org/D110410
Linking against the LibXml2::LibXml2 target has the advantage of not only importing the library, but also adding the include path as well as any definitions the library requires. In case of a static build of libxml2, eg. a define is set on Windows to remove any DLL imports and export.
LLVM already makes use of the target, but c-index-test and lldb were still linking against the library only.
The workaround for Mac OS-X that I removed seems to have also been made redundant since https://reviews.llvm.org/D84563 I believe
Differential Revision: https://reviews.llvm.org/D109975
Refactor Socket::DecodeHostAndPort() to use LLVM API over redundant
LLDB API. In particular, this means llvm::Regex, llvm::Error return
type and llvm::to_integer().
While at it, change the port type from int32_t to uint16_t. The method
never returns any value outside this range, and using the correct type
allows us to rely on getAsInteger()'s implicit overflow check.
Differential Revision: https://reviews.llvm.org/D110391
Refactor Socket::DecodeHostAndPort() to use LLVM API over redundant
LLDB API. In particular, this means llvm::Regex, llvm::Error return
type and llvm::to_integer().
While at it, change the port type from int32_t to uint16_t. The method
never returns any value outside this range, and using the correct type
allows us to rely on getAsInteger()'s implicit overflow check.
Differential Revision: https://reviews.llvm.org/D110391
getpeername will return addrlen = 2 (sizeof sa_family_t) for unnamed
sockets (those not assigned a name with bind(2)). This is typically true
for client sockets as well as those created by socketpair(2).
This GetSocketName used to crash for sockets which were connected to
these kinds of sockets. Now it returns an empty string.
Update GetRegisterInfoByName() methods to support getting registers
by a generic name independently of alt_name entries in the register
context. This makes it possible to use generic names when interacting
with gdbserver (that does not supply alt_names). It also makes it
possible to remove some of the duplicated information from register
context declarations and/or use alt_names for another purpose.
Differential Revision: https://reviews.llvm.org/D108554
Right now running `expr` to start the multiline expression editor and then
pressing enter causes an empty history empty to be created for the multiline
editor. That doesn't seem very useful for users as pressing the 'up' key will
now also bring up these empty expressions.
I don't think there is ever a use case for recalling a completely empty
expression from the history, so instead don't save those entries to the history
file and make sure we never recall them when navigating over the expression
history.
Note: This is actually a Swift downstream patch that got shipped with Apple's
LLDB for many years. However, this recently started conflicting with upstream
LLDB as D100048 added a test that made sure that empty expression entries don't
crash LLDB. Apple's LLDB was never affected by this crash as it never saved
empty expressions in the first place.
Reviewed By: augusto2112
Differential Revision: https://reviews.llvm.org/D108983