LLDB needs some minor changes to adopt PrettyStackTrace after https://reviews.llvm.org/D27683.
We remove our own SetCrashDescription() function and use LLVM-provided RAII objects instead.
We also make sure LLDB doesn't define __crashtracer_info__ which would collide with LLVM's definition.
Differential Revision: https://reviews.llvm.org/D27735
llvm-svn: 289711
Rationale:
scripts/Python/modules: android is excluded at a higher level, so no point in
checking here
tools/lldb-mi: lldb-mi builds fine (with some cosmetic tweaks) on android, and
there is no reason it shouldn't.
tools/lldb-server: LLDB_DISABLE_LIBEDIT/CURSES already take the platform into
account, so there is no point in checking again.
I am reasonably confident this should not break the build on any platform, but
I'll keep an eye out on the bots.
llvm-svn: 288661
I added a "thread-stop-format" to distinguish between the form
that is just the thread info (since the stop printing immediately prints
the frame info) and one with more frame 0 info - which is useful for
"thread list" and the like.
I also added a frame.no-debug boolean to the format entities so you can
print frame information differently between frames with source info and those
without.
This closes https://reviews.llvm.org/D26383.
<rdar://problem/28273697>
llvm-svn: 286288
Summary: This tool is only built on Darwin, and the name darwin-debug matches the Xcode project. We should have this in sync unless there is a good reason not to.
Reviewers: zturner, tfiala, labath
Subscribers: labath, mgorny, lldb-commits
Differential Revision: https://reviews.llvm.org/D25745
llvm-svn: 285356
Summary:
If Python is installed to a location that contains spaces
(e.g. "C:\Program Files\Python3") then the build fails while attempting
to run the modify-python-lldb.py script because the path to the Python
executable is not double-quoted before being passed to the shell. The
fix consists of letting Python handle the formatting of the command
line, since subprocess.Popen() is perfectly capable of handling paths
containing spaces if it's given the command and arguments as a list
instead of a single pre-formatted string.
Reviewers: zturner, clayborg
Subscribers: lldb-commits
Differential Revision: https://reviews.llvm.org/D25396
llvm-svn: 284100
Summary:
This patch adds a CMake option LLDB_BUILD_FRAMEWORK, which builds libLLDB as a macOS framework instead of as a *nix shared library.
With this patch any LLDB executable that has the INCLUDE_IN_FRAMEWORK option set will be built into the Framework's resources directory, and a symlink to the exeuctable will be placed under the build directory's bin folder. Creating the symlinks allows users to run commands from the build directory without altering the workflow.
The framework generated by this patch passes the LLDB test suite, but has not been tested beyond that. It is not expected to be fully ready to ship, but it is a first step.
With this patch binaries that are placed inside the framework aren't being properly installed. Fixing that would increase the patch size significantly, so I'd like to do that in a follow-up.
Reviewers: zturner, tfiala
Subscribers: beanz, lldb-commits, mgorny
Differential Revision: https://reviews.llvm.org/D24749
llvm-svn: 282110
This change introduces optional marking of the column within a source
line where a thread is stopped. This marking will show up when the
source code for a thread stop is displayed, when the debug info
knows the column information, and if the optional column marking is
enabled.
There are two separate methods for handling the marking of the stop
column:
* via ANSI terminal codes, which are added inline to the source line
display. The default ANSI mark-up is to underline the column.
* via a pure text-based caret that is added in the appropriate column
in a newly-inserted blank line underneath the source line in
question.
There are some new options that control how this all works.
* settings set stop-show-column
This takes one of 4 values:
* ansi-or-caret: use the ANSI terminal code mechanism if LLDB
is running with color enabled; if not, use the caret-based,
pure text method (see the "caret" mode below).
* ansi: only use the ANSI terminal code mechanism to highlight
the stop line. If LLDB is running with color disabled, no
stop column marking will occur.
* caret: only use the pure text caret method, which introduces
a newly-inserted line underneath the current line, where
the only character in the new line is a caret that highlights
the stop column in question.
* none: no stop column marking will be attempted.
* settings set stop-show-column-ansi-prefix
This is a text format that indicates the ANSI formatting
code to insert into the stream immediately preceding the
column where the stop column character will be marked up.
It defaults to ${ansi.underline}; however, it can contain
any valid LLDB format codes, e.g.
${ansi.fg.red}${ansi.bold}${ansi.underline}
* settings set stop-show-column-ansi-suffix
This is the text format that specifies the ANSI terminal
codes to end the markup that was started with the prefix
described above. It defaults to: ${ansi.normal}. This
should be sufficient for the common cases.
Significant leg-work was done by Adrian Prantl. (Thanks, Adrian!)
differential review: https://reviews.llvm.org/D20835
reviewers: clayborg, jingham
llvm-svn: 282105
Serialize breakpoint names & the hardware_requested attributes.
Also added a few missing affordances to SBBreakpoint whose absence
writing the tests pointed out.
<rdar://problem/12611863>
llvm-svn: 282036
This change adds support for the gtests that require input data
in the Inputs files. This is done through a new Xcode script
phase that runs the scripts/Xcode/prepare-gtest-run-dir.sh script.
That script simply copies the contents of all unittests/**/Inputs
dirs into ${TARGET_BUILD_DIR}/Inputs before running the test.
This change also renames the Xcode 'gtest-for-debugging' to
'gtest-build', and makes the gtest "build and run" target
depend on gtest-build. This reduces replication within the
targets. gtest .c/.cpp files now should only be added to
the gtest-build target.
llvm-svn: 281913
Moved the guts of the code from CommandObjectBreakpoint to Target (should
have done it that way in the first place.) Added an SBBreakpointList class
so there's a way to specify which breakpoints to serialize and to report the
deserialized breakpoints.
<rdar://problem/12611863>
llvm-svn: 281520
Summary:
- Added an API to public interface that provides permissions (RWX) of
individual sections of an object file
- Earlier, there was no way to find out this information through SB
APIs
- A possible use case of this API is:
when a user wants to know the sections that have executable machine
instructions and want to write a tool on top of LLDB based on this
information
- Differential Revision: https://reviews.llvm.org/D24251
llvm-svn: 280924
*** to conform to clang-format’s LLVM style. This kind of mass change has
*** two obvious implications:
Firstly, merging this particular commit into a downstream fork may be a huge
effort. Alternatively, it may be worth merging all changes up to this commit,
performing the same reformatting operation locally, and then discarding the
merge for this particular commit. The commands used to accomplish this
reformatting were as follows (with current working directory as the root of
the repository):
find . \( -iname "*.c" -or -iname "*.cpp" -or -iname "*.h" -or -iname "*.mm" \) -exec clang-format -i {} +
find . -iname "*.py" -exec autopep8 --in-place --aggressive --aggressive {} + ;
The version of clang-format used was 3.9.0, and autopep8 was 1.2.4.
Secondly, “blame” style tools will generally point to this commit instead of
a meaningful prior commit. There are alternatives available that will attempt
to look through this change and find the appropriate prior commit. YMMV.
llvm-svn: 280751
Summary:
- copies the new file in the cmake build
- adds an additional import statement
- marks the test as no-debug-info specific, as it seems to be testing a python feature
Reviewers: granata.enrico
Subscribers: lldb-commits
Differential Revision: https://reviews.llvm.org/D24074
llvm-svn: 280261
This class enables one to easily write a synthetic child provider by writing a class that returns pairs of names and primitive Python values - the base class then converts those into LLDB SBValues
Comes with a test case
llvm-svn: 280172
Take 2, with missing cmake line fixed. Build tested on
Ubuntu 14.04 with clang-3.6.
See docs/structured_data/StructuredDataPlugins.md for details.
differential review: https://reviews.llvm.org/D22976
reviewers: clayborg, jingham
llvm-svn: 279202
Change r278527 was filtering out too many libraries.
The Xcode lldb-gtest target depends on linking libgtest*.a,
but those were not being included. This caused the lldb-gtest
linkage step to fail to find a main entry point that is present
in the filtered out libs.
This change restores the libgtest* libraries to the link list
by whitelisting them in the filter.
llvm-svn: 278552
The Xcode macOS build of LLDB is currently broken after
https://reviews.llvm.org/D23232 landed, see
http://lab.llvm.org:8080/green/job/lldb_build_test/20014/console,
because we’re trying to link against all .a files found in the
llvm-build/lib directory. Let’s be more specific in what we link
against. This patch applies a regexp to only use “libclang.*”,
“libLLVM.*” and not “libclang_rt.*” static archives.
Change by Kuba Mracek (formerly Kuba Brecka)
See review here:
https://reviews.llvm.org/D23444
Reviewers: tfiala, compnerd
llvm-svn: 278527
Summary:
This is already done when building for linux with the CMake build
system. This functionality disappeared recently when some of the build
scripts used by the xcode build system changed.
Reviewers: tfiala, clayborg
Subscribers: lldb-commits
Differential Revision: http://reviews.llvm.org/D22233
llvm-svn: 275134
Summary:
This patch fills in the implementation of GetMemoryRegions() on the Linux and Mac OS core file implementations of lldb_private::Process (ProcessElfCore::GetMemoryRegions and ProcessMachCore::GetMemoryRegions.) The GetMemoryRegions API was added under: http://reviews.llvm.org/D20565
The patch re-uses the m_core_range_infos list that was recently added to implement GetMemoryRegionInfo in both ProcessElfCore and ProcessMachCore to ensure the returned regions match the regions returned by Process::GetMemoryRegionInfo(addr_t load_addr, MemoryRegionInfo ®ion_info).
Reviewers: clayborg
Subscribers: labath, lldb-commits
Differential Revision: http://reviews.llvm.org/D21751
llvm-svn: 274741
- if a synthetic child comes from the same hierarchy as its parent object, then it can't be cached by SharedPointer inside the synthetic provider, or it will cause a reference loop;
- but, if a synthetic child is made from whole cloth (e.g. from an expression, a memory region, ...), then it better be cached by SharedPointer, or it will be cleared out and cause an assert() to fail if used at a later point
For most cases of self-rooted synthetic children, we have a flag we set "IsSyntheticChildrenGenerated", but we were not using it to track caching. So, what ended up happening is each provider would set up its own cache, and if it got it wrong, a hard to diagnose crash would ensue
This patch fixes that by centralizing caching in ValueObjectSynthetic - if a provider returns a self-rooted child (as per the flag), then it gets cached centrally by the ValueObject itself
This cache is used only for lifetime management and not later retrieval of child values - a different cache handles that (because we might have a mix of self-rooted and properly nested child values for the same parent, we can't trivially use this lifetime cache for retrieval)
Fixes rdar://26480007
llvm-svn: 274683
This:
a) teaches PythonCallable to look inside a callable object
b) teaches PythonCallable to discover whether a callable method is bound
c) teaches lldb.command to dispatch to either the older 4 argument version or the newer 5 argument version
llvm-svn: 273640
On OS X systems, look for /Applications/CMake.app and ~/Applications/CMake.app
versions of the cmake command line binary when trying harder to find a cmake not
on the system path.
Reviewers: clayborg
Subscribers: lldb-commits
Differential Revision: http://reviews.llvm.org/D20303
llvm-svn: 269713
within a source file.
This isn't done, I need to make the name match smarter (right now it requires an
exact match which is annoying for methods of a class in a namespace.
Also, though we use it in tests all over the place, it doesn't look like we have
a test for Source Regexp breakpoints by themselves, I'll add that in a follow-on patch.
llvm-svn: 267834
Summary:
Do not assume that liblldb.so is located in $(lldb -P)/../../../lib
when creating the _lldb python symlink. Instead, use the path passed
to LLVM_LIBDIR_SUFFIX, defaulting to $(lldb -P)/../../../lib when this
variable is not set.
Reviewers: vharron, emaste, zturner
Subscribers: zturner, labath, lldb-commits, sas
Differential Revision: http://reviews.llvm.org/D19067
llvm-svn: 267462
This code was getting evaluated unintentionally at binding
generation time instead of binding file compilation time.
Addresses:
https://bugs.swift.org/browse/SR-1192
llvm-svn: 265829
Summary:
This fixes a leak introduced by some of these changes:
r257644
r250530
r250525
The changes made in these patches result in leaking the FILE* passed
to SetImmediateOutputFile. GetStream() will dup() the fd held by the
python caller and create a new FILE*. It will then pass this FILE*
to SetImmediateOutputFile, which always uses the flag
transfer_ownership=false when it creates a File from the FILE*.
Since transfer_ownership is false, the lldb File destructor will not
close the underlying FILE*. Because this FILE* came from a dup-ed fd,
it will also not be closed when the python caller closes its file.
Leaking the FILE* causes issues if the same file is used multiple times
by different python callers during the same lldb run, even if these
callers open and close the python file properly, as you can end up
with issues due to multiple buffered writes to the same file.
Reviewers: granata.enrico, zturner, clayborg
Subscribers: zturner, lldb-commits, sas
Differential Revision: http://reviews.llvm.org/D18459
Change by Francis Ricci <fjricci@fb.com>
llvm-svn: 264476
This feature is controlled by an expression command option, a target property and the
SBExpressionOptions setting. FixIt's are only applied to UserExpressions, not UtilityFunctions,
those you have to get right when you make them.
This is just a first stage. At present the fixits are applied silently. The next step
is to tell the user about the applied fixit.
<rdar://problem/25351938>
llvm-svn: 264379
This patch adds ThreadSanitizer support into LLDB:
- Adding a new InstrumentationRuntime plugin, ThreadSanitizerRuntime, in the same way ASan is implemented.
- A breakpoint stops in `__tsan_on_report`, then we extract all sorts of information by evaluating an expression. We then populate this into StopReasonExtendedInfo.
- SBThread gets a new API, SBThread::GetStopReasonExtendedBacktraces(), which returns TSan’s backtraces in the form of regular SBThreads. Non-TSan stop reasons return an empty collection.
- Added some test cases.
Reviewed by Greg Clayton.
llvm-svn: 264162
We are using hardlinks instead of symlinks, and we attempted to
have some logic where we don't re-create the link if the target
file already exists. This logic is faulty, however, when you
manually delete the source file (e.g. liblldb.dll) and then rebuild
lldb so that a brand new liblldb.dll gets written. Now the two files
have different inodes, but the target exists, so we would not remake
the link and the target would become stale.
We fix this by only doing the optimization if they are really the
exact same file (by comparing inode numbers), and if they are not
the same file but the target exists, we delete it and re-create
the link.
llvm-svn: 263844
The swig typemaps had some magic for output File *'s on OS X that made:
SBDebugger.GetOutputFileHandle()
actually work. That was protected by a "#ifdef __MACOSX__", but the corresponding define
got lost going from the Darwin shell scripts to the python scripts for running
swig, so the code was elided. I need to pass the define to SWIG, but only when
targetting Darwin.
So I added a target-platform argument to prepare_bindings, and if that
is Darwin, I pass -D__APPLE__ to swig, and that activates this code again, and
GetOutputFileHandle works again. Note, I only pass that argument for the Xcode
build. I'm sure it is possible to do that for cmake, but my cmake-foo is weak.
I should have been able to write a test for this by creating a debugger, setting the
output file handle to something file, writing to it, getting the output file handle
and reading it. But SetOutputFileHandle doesn't seem to work from Python, so I'd
have to write a pexpect test to test this, which I'd rather not do.
llvm-svn: 263183
That way you can set offset breakpoints that will move as the function they are
contained in moves (which address breakpoints can't do...)
I don't align the new address to instruction boundaries yet, so you have to get
this right yourself for now.
<rdar://problem/13365575>
llvm-svn: 263049
Summary:
This makes cloning (and therefore the whole build) faster.
The checkout step goes from ~4m to ~30s on my host.
Reviewers: tfiala
Subscribers: lldb-commits
Differential Revision: http://reviews.llvm.org/D17425
llvm-svn: 262513
working directory by default -- a typical security problem that we
need to be more conservative about.
It adds a new target setting, target.load-cwd-lldbinit which may
be true (always read $cwd/.lldbinit), false (never read $cwd/.lldbinit)
or warn (warn if there is a $cwd/.lldbinit and don't read it). The
default is set to warn. If this is met with unhappiness, we can look
at changing the default to true (to match current behavior) on a
different platform.
This does not affect reading of ~/.lldbinit - that will still be read,
as before. If you run lldb in your home directory, it will not warn
about the presence of a .lldbinit file there.
I had to add two SB API - SBHostOS::GetUserHomeDirectory and
SBFileSpec::AppendPathComponent - for the lldb driver code to be
able to get the home directory path in an OS neutral manner.
The warning text is
There is a .lldbinit file in the current directory which is not being read.
To silence this warning without sourcing in the local .lldbinit,
add the following to the lldbinit file in your home directory:
settings set target.load-cwd-lldbinit false
To allow lldb to source .lldbinit files in the current working directory,
set the value of this variable to true. Only do so if you understand and
accept the security risk.
<rdar://problem/24199163>
llvm-svn: 261280
Summary:
This does not yet give us a clean testsuite run but it does help with:
1. Actually building on linux
2. Run the testsuite with over 70% tests passing on linux.
Reviewers: tfiala, labath, zturner
Subscribers: lldb-commits
Differential Revision: http://reviews.llvm.org/D17182
llvm-svn: 260721
The explicit APIs on SBValue obviously remain if one wants to be explicit in intent, or override this guess, but since __int__() has to pick one, an educated guess is definitely better than than always going to signed regardless
Fixes rdar://24556976
llvm-svn: 260349
This change restores the Xcode build to working after Makefile support
was stripped from LLVM and clang recently.
With this change, the Xcode build now requires cmake (2.8.12.2+).
The cmake must either be on the path that Xcode sees, or it must
exist in one of the following locations:
* /usr/local/bin/cmake
* /opt/local/bin/cmake
* $HOME/bin/cmake
If the ninja build tool is present on the path, it will be used.
If not, ninja will be cloned (via git), bootstrap-built, and
used for the llvm/clang build.
LLDB now requires a minimum deployment target of OS X 10.9. Prior
to this, it was 10.8. The llvm/clang cmake build will not run
with Xcode 7.2 or Xcode 7.3 beta's compiler with the minimum
deployment target set to anything lower than 10.9. This is
related to #include <atomic>.
When llvm or clang source code does not exist in the lldb tree,
it will be cloned via git using http://llvm.org/git/{project}.git.
Previously it used SVN. If this causes any heartache, we can
make this smarter, autodetect an embedded svn and use svn instead.
(And/or use SVN if a git command is not available).
This change also fixes an lldb-mi linkage failure (needed
libncurses) as exposed by one of the LLVM libs.
llvm-svn: 259027
SUMMARY:
Get the load address for the address given by symbol and function.
Earlier, this was done for function only, this patch does it for symbol too.
This patch also adds TestAvoidBreakpointInDelaySlot.py to test this change.
Reviewers: clayborg
Subscribers: labath, zturner, mohit.bhakkad, sagar, jaydeep, lldb-commits
Differential Revision: http://reviews.llvm.org/D16049
llvm-svn: 258919
SBProcess::ReadMemory and other related functions such as
WriteMemory are returning Python string() objects. This means
that in Python 3 that are returning Unicode objects. In reality
they should be returning bytes objects which is the same as a string
in Python 2, but different in Python 3. This patch updates the
generated SWIG code to return Python bytes objects for all
memory related functions.
One quirk of this patch is that the C++ signature of ReadCStringFromMemory
has it writing c-string data into a void*. This confuses our swig
typemaps which expect that a void* means byte data. So I hacked up
a custom typemap which maps this specific function to treat the
void* as string data instead of byte data.
llvm-svn: 258743
This needs to be able to handle bytes, strings, and bytearray objects.
In Python 2 this was easy because bytes and strings are the same thing,
but in Python 3 the 2 cases need to be handled separately. So as not
to mix raw Python C API code with PythonDataObjects code, I've also
introduced a PythonByteArray class to PythonDataObjects to make the
paradigm used here consistent.
llvm-svn: 258741
We already have char** typemaps which were near copy-pastes of
the const char** versions. This way we have only one version that
works for both.
llvm-svn: 257670
There were a number of problems preventing this from working:
1. The SWIG typemaps for converting Python lists to and from C++
arrays were not updated for Python 3. So they were doing things
like PyString_Check instead of using the PythonString from
PythonDataObjects.
2. ProcessLauncherWindows was ignoring the environment completely.
So any test that involved launching an inferior with any kind
of environment variable would have failed.
3. The test itself was using process.GetSTDOUT(), which isn't
implemented on Windows. So this was changed to save the
value of the environment variable in a local variable and
have the debugger look at the value of the variable.
llvm-svn: 257669
* lldb::tid_t was being converted incorrectly, so this is updated to use
PythonInteger instead of manual Python Native API calls.
* OSPlugin_RegisterContextData was assuming that the result of
get_register_data was a string, when in fact it is a bytes. So this
method is updated to use PythonBytes to do the work.
llvm-svn: 257398
Summary: If six.py is simlink'd, an installation won't be able to find it unless it has access to the source tree that lldb was built from.
Reviewers: zturner
Subscribers: lldb-commits
Differential Revision: http://reviews.llvm.org/D15422
llvm-svn: 255340
We were trying to be super smart and find all the supported language
bindings. This led to us scanning the directory and treating all
subdirectories as language binding directories. This makes it
hard to add unrelated code in this folder.
Besides, we only support one at the moment - Python. And when new
ones are added it will be trivial to just add their names to a list.
So this patch gets stupider about how to look for language binding
subfolders. Just put them in a list, and use the list.
llvm-svn: 254078
This script really should not be assuming every subdirectory is
a language directory for swig generation. Using a hack to get
this working for now, but this should be solved once this script
is re-written similar to how prepare_bindings was.
llvm-svn: 254037
With this patch, the client will package up all the required
inputs into a compressed zip file, establish a connection to the
server, send the input to the server, and wait for the server to
send a response (in this case the response is just echoed back to
the client).
This gets the network communication in place, and in a subsequent
patch I will follow up with the code that actually runs swig on
the server and sends back the output instead of echoing back the
input.
llvm-svn: 254023
This version supports local generation only. It's intentionally
stupid, and does not support any kind of dependency checking.
If you run the script, it's going to call SWIG. While this is
a slow process, we are going to combine the use of the swig bot
with checked in static bindings, meaning that it won't be terribly
important to only regenerate the bindings when the input files
have actually changed.
A side benefit of this is that the implementation is drastically
simpler.
This is all experimental at the moment, but it duplicates a lot
of the logic currently found in prepare_bindings.py. There was
not a good way to reuse some of the logic without invasive changes
on that script, and since this script is still experimental, it
makes sense to just copy them over, and if / when this becomes
more mature, we can get rid of the other ones.
llvm-svn: 254022
This patch fixes two issues:
1) Popen needs to be used with universal_newlines=True by default.
This elicits automatic decoding from bytes -> string in Py3,
and has no negative effects in other Py versions.
2) The swig typemaps for converting between string and (char*, int)
did not work correctly when the length of the string was 0,
indicating an error. In this case we would try to construct a
string from uninitialized data.
3) Ironically, the bug mentioned in #2 led to a test passing on
Windows that was actually broken, because the test was written
such that the assertion was never even getting checked, so it
passed by default. So we additionally fix this test to also
fail if the method errors. By fixing this test it's now broken
on Windows, so we also xfail it.
llvm-svn: 253487
This change does not introduce static bindings. It is simply using
the pylinted cleaned up code in prepare_bindings.py.
If this breaks anyting, I'll revert immediately and figure out what
needs to be addressed. I'm looking to wrap up
the cleanup aspect of the code change (pylinted, removal of code that
implements existing python stdlib code, fixes for Xcode adoption, etc.).
llvm-svn: 253478
Added a new flag, --allow-static-binding. When specified,
if (and only if) the swig binary cannot be found, then the
LLDBWrapPython.cpp and lldb.py from the
scripts/Python/{static-binding-dir} are copied into the place where
swig would have generated them.
{static-binding-dir} defaults to static-binding, and can be
overridden with the --static-binding-dir command line argument.
The static bindings checked in are from r253424.
llvm-svn: 253448
This is only used by Xcode at the moment. It replaces the
buildSwigWrapperClasses.py and related per-script-language
scripts. It also fixes a couple bugs in those w/r/t Xcode
usage:
* the presence of the GCC_PREPROCESSOR_DEFINITIONS env var
should not be short-circuiting generation of the language
binding; rather, only if LLDB_DISABLE_PYTHON is present
within that environment variable.
* some logic around what to do when building in "non-Makefile"
mode. I've switched the handling of that to be on a
"--framework" flag - if specified, we build an OS X-style
framework; otherwise, we go with non.
Putting this up now only attached to the Xcode build so
others can look at it but not be affected by it yet.
After this, I'll tackle the finalizer, along with trying
it locally on Linux.
llvm-svn: 253317
breakpoint as "file address" so that the address breakpoint will track that
module even if it gets loaded in a different place. Also fixed the Address
breakpoint resolver so that it handles this tracking correctly.
llvm-svn: 253308
Sean Callanan