This abstracts read/write locks on the current host system. It is currently backed by pthread_rwlock_t objects so it should work on all unix systems.
We also need a way to control multi-threaded access to the process through the public API when it is running. For example it isn't a good idea to try and get stack frames while the process is running. To implement this, the lldb_private::Process class now contains a ReadWriteLock member variable named m_run_lock which is used to control the public process state. The public process state represents the state of the process as the client knows it. The private is used to control the actual current process state. So the public state of the process can be stopped, yet the private state can be running when evaluating an expression for example.
Adding the read/write lock where readers are clients that want the process to stay stopped, and writers are clients that run the process, allows us to accurately control multi-threaded access to the process.
Switched the SBThread and SBFrame over to us shared pointers to the ExecutionContextRef class instead of making their own class to track this. This fixed an issue with assigning on SBFrame to another and will also centralize the code that tracks weak references to execution context objects into one location.
llvm-svn: 154099
load notification for the first load) then we will set it the runtime to NULL and won't re-search for it.
Added a way for the dynamic loader to force a re-search, since it knows the world has changed.
llvm-svn: 152453
Fixed STDERR to not be opened as readable. Also cleaned up some of the code that implemented the file actions as some of the code was using the wrong variables, they now use the right ones (in for stdin, out for stdout, err for stderr).
llvm-svn: 152102
weak reference back to the Module. We were crashing when trying to make a
memory object file since it was trying to get the object in the Module
constructor before the "Module *" had been put into a shared pointer, and the
module was trying to initialize a weak pointer back to it.
llvm-svn: 151397
to the __PAGEZERO segment on darwin. The dynamic loader now correctly doesn't
slide __PAGEZERO and it also registers it as an invalid region of memory. This
allows us to not make any memory requests from the local or remote debug session
for any addresses in this region. Stepping performance can improve when uninitialized
local variables that point to locations in __PAGEZERO are attempted to be read
from memory as we won't even make the memory read or write request.
llvm-svn: 151128
the lldb_private::StackFrame objects hold onto a weak pointer to the thread
object. The lldb_private::StackFrame objects the the most volatile objects
we have as when we are doing single stepping, frames can often get lost or
thrown away, only to be re-created as another object that still refers to the
same frame. We have another bug tracking that. But we need to be able to
have frames no longer be able to get the thread when they are not part of
a thread anymore, and this is the first step (this fix makes that possible
but doesn't implement it yet).
Also changed lldb_private::ExecutionContextScope to return shared pointers to
all objects in the execution context to further thread harden the internals.
llvm-svn: 150871
Tracking modules down when you have a UUID and a path has been improved.
DynamicLoaderDarwinKernel no longer parses mach-o load commands and it
now uses the memory based modules now that we can load modules from memory.
Added a target setting named "target.exec-search-paths" which can be used
to supply a list of directories to use when trying to look for executables.
This allows one or more directories to be used when searching for modules
that may not exist in the SDK/PDK. The target automatically adds the directory
for the main executable to this list so this should help us in tracking down
shared libraries and other binaries.
llvm-svn: 150426
user space programs. The core file support is implemented by making a process
plug-in that will dress up the threads and stack frames by using the core file
memory.
Added many default implementations for the lldb_private::Process functions so
that plug-ins like the ProcessMachCore don't need to override many many
functions only to have to return an error.
Added new virtual functions to the ObjectFile class for extracting the frozen
thread states that might be stored in object files. The default implementations
return no thread information, but any platforms that support core files that
contain frozen thread states (like mach-o) can make a module using the core
file and then extract the information. The object files can enumerate the
threads and also provide the register state for each thread. Since each object
file knows how the thread registers are stored, they are responsible for
creating a suitable register context that can be used by the core file threads.
Changed the process CreateInstace callbacks to return a shared pointer and
to also take an "const FileSpec *core_file" parameter to allow for core file
support. This will also allow for lldb_private::Process subclasses to be made
that could load crash logs. This should be possible on darwin where the crash
logs contain all of the stack frames for all of the threads, yet the crash
logs only contain the registers for the crashed thrad. It should also allow
some variables to be viewed for the thread that crashed.
llvm-svn: 150154
Fixed "target modules list" (aliased to "image list") to output more information
by default. Modified the "target modules list" to have a few new options:
"--header" or "-h" => show the image header address
"--offset" or "-o" => show the image header address offset from the address in the file (the slide applied to the shared library)
Removed the "--symfile-basename" or "-S" option, and repurposed it to
"--symfile-unique" "-S" which will show the symbol file if it differs from
the executable file.
ObjectFile's can now be loaded from memory for cases where we don't have the
files cached locally in an SDK or net mounted root. ObjectFileMachO can now
read mach files from memory.
Moved the section data reading code into the ObjectFile so that the object
file can get the section data from Process memory if the file is only in
memory.
lldb_private::Module can now load its object file in a target with a rigid
slide (very common operation for most dynamic linkers) by using:
bool
Module::SetLoadAddress (Target &target, lldb::addr_t offset, bool &changed)
lldb::SBModule() now has a new constructor in the public interface:
SBModule::SBModule (lldb::SBProcess &process, lldb::addr_t header_addr);
This will find an appropriate ObjectFile plug-in to load an image from memory
where the object file header is at "header_addr".
llvm-svn: 149804
frames might go away (the object itself, not the actual logical frame) when
we are single stepping due to the way we currently sometimes end up flushing
frames when stepping in/out/over. They later will come back to life
represented by another object yet they have the same StackID. Now when you get
a lldb::SBFrame object, it will track the frame it is initialized with until
the thread goes away or the StackID no longer exists in the stack for the
thread it was created on. It uses a weak_ptr to both the frame and thread and
also stores the StackID. These three items allow us to determine when the
stack frame object has gone away (the weak_ptr will be NULL) and allows us to
find the correct frame again. In our test suite we had such cases where we
were just getting lucky when something like this happened:
1 - stop at breakpoint
2 - get first frame in thread where we stopped
3 - run an expression that causes the program to JIT and run code
4 - run more expressions on the frame from step 2 which was very very luckily
still around inside a shared pointer, yet, not part of the current
thread (a new stack frame object had appeared with the same stack ID and
depth).
We now avoid all such issues and properly keep up to date, or we start
returning errors when the frame doesn't exist and always responds with
invalid answers.
Also fixed the UserSettingsController (not going to rewrite this just yet)
so that it doesn't crash on shutdown. Using weak_ptr's came in real handy to
track when the master controller has already gone away and this allowed me to
pull out the previous NotifyOwnerIsShuttingDown() patch as it is no longer
needed.
llvm-svn: 149231
due to RTTI worries since llvm and clang don't use RTTI, but I was able to
switch back with no issues as far as I can tell. Once the RTTI issue wasn't
an issue, we were looking for a way to properly track weak pointers to objects
to solve some of the threading issues we have been running into which naturally
led us back to std::tr1::weak_ptr. We also wanted the ability to make a shared
pointer from just a pointer, which is also easily solved using the
std::tr1::enable_shared_from_this class.
The main reason for this move back is so we can start properly having weak
references to objects. Currently a lldb_private::Thread class has a refrence
to its parent lldb_private::Process. This doesn't work well when we now hand
out a SBThread object that contains a shared pointer to a lldb_private::Thread
as this SBThread can be held onto by external clients and if they end up
using one of these objects we can easily crash.
So the next task is to start adopting std::tr1::weak_ptr where ever it makes
sense which we can do with lldb_private::Debugger, lldb_private::Target,
lldb_private::Process, lldb_private::Thread, lldb_private::StackFrame, and
many more objects now that they are no longer using intrusive ref counted
pointer objects (you can't do std::tr1::weak_ptr functionality with intrusive
pointers).
llvm-svn: 149207
parser has hitherto been an implementation waiting
for a use. I have now tied the '-o' option for
the expression command -- which indicates that the
result is an Objective-C object and needs to be
printed -- to the ExpressionParser, which
communicates the desired type to Clang.
Now, if the result of an expression is determined
by an Objective-C method call for which there is
no type information, that result is implicitly
cast to id if and only if the -o option is passed
to the expression command. (Otherwise if there
is no explicit cast Clang will issue an error.
This behavior is identical to what happened before
r146756.)
Also added a testcase for -o enabled and disabled.
llvm-svn: 147099
size_t
SBProcess::ReadCStringFromMemory (addr_t addr, void *buf, size_t size, lldb::SBError &error);
uint64_t
SBProcess::ReadUnsignedFromMemory (addr_t addr, uint32_t byte_size, lldb::SBError &error);
lldb::addr_t
SBProcess::ReadPointerFromMemory (addr_t addr, lldb::SBError &error);
These ReadCStringFromMemory() has some SWIG type magic that makes it return the
python string directly and the "buf" is not needed:
error = SBError()
max_cstr_len = 256
cstr = lldb.process.ReadCStringFromMemory (0x1000, max_cstr_len, error)
if error.Success():
....
The other two functions behave as expteced. This will make it easier to get integer values
from the inferior process that are correctly byte swapped. Also for pointers, the correct
pointer byte size will be used.
Also cleaned up a few printf style warnings for the 32 bit lldb build on darwin.
llvm-svn: 146636
will allow us to represent a process/thread ID using a pointer for the OS
plug-ins where they might want to represent the process or thread ID using
the address of the process or thread structure.
llvm-svn: 145644
we say that the vectors of DWARFDebugInfoEntry objects were the highest on the
the list.
With these changes we cut our memory usage by 40%!!! I did this by reducing
the size of the DWARFDebugInfoEntry from a previous:
uint32_t offset
uint32_t parent_idx
uint32_t sibling_idx
Abbrev * abbrev_ptr
which was 20 bytes, but rounded up to 24 bytes due to alignment. Now we have:
uint32_t offset
uint32_t parent_idx
uint32_t sibling_idx
uint32_t abbr_idx:15, // 32767 possible abbreviation codes
has_children:1, // 0 = no children, 1 = has children
tag:16; // DW_TAG_XXX value
This gets us down to 16 bytes per DIE. I tested some VERY large DWARF files
(900MB) and found there were only ~700 unique abbreviations, so 32767 should
be enough for any sane compiler. If it isn't there are built in assertions
that will fire off and tell us.
llvm-svn: 144975
turned out to be unitialized data in the ProcessLaunchInfo default constructor.
Turning on MallocScribble in the environment helped track this down.
When we launch and attach using the host layer, we now inform the process that
it shouldn't detach when by calling an accessor.
llvm-svn: 144882
the thread specific data and were destroying the thread specfic data more
than once.
Also added the ability to ask a lldb::StateType if it is stopped with an
additional paramter of "must_exist" which means that the state must be a
stopped state for a process that still exists. This means that eStateExited
and eStateUnloaded will no longer return true if "must_exist" is set to true.
llvm-svn: 144875
Bill Wendling
Greg Clayton
Jim Ingham
Han Ming Ong
Sean Callanan