aboutsummaryrefslogtreecommitdiff
path: root/gdb/python/python.c
AgeCommit message (Collapse)AuthorFilesLines
2023-06-03[gdb] Fix typosTom de Vries1-1/+1
Fix a few typos: - implemention -> implementation - convertion(s) -> conversion(s) - backlashes -> backslashes - signoring -> ignoring - (un)ambigious -> (un)ambiguous - occured -> occurred - hidding -> hiding - temporarilly -> temporarily - immediatelly -> immediately - sillyness -> silliness - similiar -> similar - porkuser -> pokeuser - thats -> that - alway -> always - supercede -> supersede - accomodate -> accommodate - aquire -> acquire - priveleged -> privileged - priviliged -> privileged - priviledges -> privileges - privilige -> privilege - recieve -> receive - (p)refered -> (p)referred - succesfully -> successfully - successfuly -> successfully - responsability -> responsibility - wether -> whether - wich -> which - disasbleable -> disableable - descriminant -> discriminant - construcstor -> constructor - underlaying -> underlying - underyling -> underlying - structureal -> structural - appearences -> appearances - terciarily -> tertiarily - resgisters -> registers - reacheable -> reachable - likelyhood -> likelihood - intepreter -> interpreter - disassemly -> disassembly - covnersion -> conversion - conviently -> conveniently - atttribute -> attribute - struction -> struct - resonable -> reasonable - popupated -> populated - namespaxe -> namespace - intialize -> initialize - identifer(s) -> identifier(s) - expection -> exception - exectuted -> executed - dungerous -> dangerous - dissapear -> disappear - completly -> completely - (inter)changable -> (inter)changeable - beakpoint -> breakpoint - automativ -> automatic - alocating -> allocating - agressive -> aggressive - writting -> writing - reguires -> requires - registed -> registered - recuding -> reducing - opeartor -> operator - ommitted -> omitted - modifing -> modifying - intances -> instances - imbedded -> embedded - gdbaarch -> gdbarch - exection -> execution - direcive -> directive - demanged -> demangled - decidely -> decidedly - argments -> arguments - agrument -> argument - amespace -> namespace - targtet -> target - supress(ed) -> suppress(ed) - startum -> stratum - squence -> sequence - prompty -> prompt - overlow -> overflow - memember -> member - languge -> language - geneate -> generate - funcion -> function - exising -> existing - dinking -> syncing - destroh -> destroy - clenaed -> cleaned - changep -> changedp (name of variable) - arround -> around - aproach -> approach - whould -> would - symobl -> symbol - recuse -> recurse - outter -> outer - freeds -> frees - contex -> context Tested on x86_64-linux. Reviewed-By: Tom Tromey <tom@tromey.com>
2023-05-23Add global_context parameter to gdb.parse_and_evalTom Tromey1-6/+22
This adds a 'global_context' parse_and_eval to gdb.parse_and_eval. This lets users request a parse that is done at "global scope". I considered letting callers pass in a block instead, with None meaning "global" -- but then there didn't seem to be a clean way to express the default for this parameter. Reviewed-By: Eli Zaretskii <eliz@gnu.org>
2023-05-23Implement gdb.execute_miTom Tromey1-0/+5
This adds a new Python function, gdb.execute_mi, that can be used to invoke an MI command but get the output as a Python object, rather than a string. This is done by implementing a new ui_out subclass that builds a Python object. Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=11688 Reviewed-By: Eli Zaretskii <eliz@gnu.org>
2023-05-05gdb/python: add mechanism to manage Python initialization functionsAndrew Burgess1-37/+4
Currently, when we add a new python sub-system to GDB, e.g. py-inferior.c, we end up having to create a new function like gdbpy_initialize_inferior, which then has to be called from the function do_start_initialization in python.c. In some cases (py-micmd.c and py-tui.c), we have two functions gdbpy_initialize_*, and gdbpy_finalize_*, with the second being called from finalize_python which is also in python.c. This commit proposes a mechanism to manage these initialization and finalization calls, this means that adding a new Python subsystem will no longer require changes to python.c or python-internal.h, instead, the initialization and finalization functions will be registered directly from the sub-system file, e.g. py-inferior.c, or py-micmd.c. The initialization and finalization functions are managed through a new class gdbpy_initialize_file in python-internal.h. This class contains a single global vector of all the initialization and finalization functions. In each Python sub-system we create a new gdbpy_initialize_file object, the object constructor takes care of registering the two callback functions. Now from python.c we can call static functions on the gdbpy_initialize_file class which take care of walking the callback list and invoking each callback in turn. To slightly simplify the Python sub-system files I added a new macro GDBPY_INITIALIZE_FILE, which hides the need to create an object. We can now just do this: GDBPY_INITIALIZE_FILE (gdbpy_initialize_registers); One possible problem with this change is that there is now no guaranteed ordering of how the various sub-systems are initialized (or finalized). To try and avoid dependencies creeping in I have added a use of the environment variable GDB_REVERSE_INIT_FUNCTIONS, this is the same environment variable used in the generated init.c file. Just like with init.c, when this environment variable is set we reverse the list of Python initialization (and finalization) functions. As there is already a test that starts GDB with the environment variable set then this should offer some level of protection against dependencies creeping in - though for full protection I guess we'd need to run all gdb.python/*.exp tests with the variable set. I have tested this patch with the environment variable set, and saw no regressions, so I think we are fine right now. One other change of note was for gdbpy_initialize_gdb_readline, this function previously returned void. In order to make this function have the correct signature I've updated its return type to int, and we now return 0 to indicate success. All of the other initialize (and finalize) functions have been made static within their respective sub-system files. There should be no user visible changes after this commit.
2023-05-01gdb: move struct ui and related things to ui.{c,h}Simon Marchi1-0/+1
I'd like to move some things so they become methods on struct ui. But first, I think that struct ui and the related things are big enough to deserve their own file, instead of being scattered through top.{c,h} and event-top.c. Change-Id: I15594269ace61fd76ef80a7b58f51ff3ab6979bc
2023-04-06Use unique_xmalloc_ptr in apply_ext_lang_type_printersTom Tromey1-4/+6
This changes apply_ext_lang_type_printers to use unique_xmalloc_ptr, removing some manual memory management. Regression tested on x86-64 Fedora 36. Approved-By: Simon Marchi <simon.marchi@efficios.com>
2023-03-09gdb, gdbserver, gdbsupport: fix whitespace issuesSimon Marchi1-1/+1
Replace spaces with tabs in a bunch of places. Change-Id: If0f87180f1d13028dc178e5a8af7882a067868b0
2023-02-27Fix value chain use-after-freeTom Tromey1-3/+5
Hannes filed a bug showing a crash, where a pretty-printer written in Python could cause a use-after-free. He sent a patch, but I thought a different approach was needed. In a much earlier patch (see bug #12533), we changed the Python code to release new values from the value chain when constructing a gdb.Value. The rationale for this is that if you write a command that does a lot of computations in a loop, all the values will be kept live by the value chain, resulting in gdb using a large amount of memory. However, suppose a value is passed to Python from some code in gdb that needs to use the value after the call into Python. In this scenario, value_to_value_object will still release the value -- and because gdb code doesn't generally keep strong references to values (a consequence of the ancient decision to use the value chain to avoid memory management), this will result in a use-after-free. This scenario can happen, as it turns out, when a value is passed to Python for pretty-printing. Now, normally this route boxes the value via value_to_value_object_no_release, avoiding the problematic release from the value chain. However, if you then call Value.cast, the underlying value API might return the same value, when is then released from the chain. This patch fixes the problem by changing how value boxing is done. value_to_value_object no longer removes a value from the chain. Instead, every spot in gdb that might construct new values uses a scoped_value_mark to ensure that the requirements of bug #12533 are met. And, because incoming values aren't ever released from the chain (the Value.cast one comes earlier on the chain than the scoped_value_mark), the bug can no longer occur. (Note that many spots in the Python layer already take this approach, so not many places needed to be touched.) In the future I think we should replace the use of raw "value *" with value_ref_ptr pretty much everywhere. This will ensure lifetime safety throughout gdb. The test case in this patch comes from Hannes' original patch. I only made a trivial ("require") change to it. However, while this fails for him, I can't make it fail on this machine; nevertheless, he tried my patch and reported the bug as being fixed. Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=30044
2023-02-27gdb, python: do minor modernization in execute_gdb_commandTankut Baris Aktemur1-12/+13
Use nullptr instead of NULL and boolify two local variables in execute_gdb_command. Approved-By: Tom Tromey <tom@tromey.com>
2023-02-13gdb/python: deallocate tui window factories at Python shut downAndrew Burgess1-0/+1
The previous commit relied on spotting when a Python defined TUI window factory was deleted. I spotted that the window factories are not deleted when GDB shuts down its Python environment, they are only deleted when one window factory replaces another. Consider this example Python script: class TestWindowFactory: def __init__(self, msg): self.msg = msg print("Entering TestWindowFactory.__init__: %s" % self.msg) def __call__(self, tui_win): print("Entering TestWindowFactory.__call__: %s" % self.msg) return TestWindow(tui_win, self.msg) def __del__(self): print("Entering TestWindowFactory.__del__: %s" % self.msg) gdb.register_window_type("test_window", TestWindowFactory("A")) gdb.register_window_type("test_window", TestWindowFactory("B")) And this GDB session: (gdb) source tui.py Entering TestWindowFactory.__init__: A Entering TestWindowFactory.__init__: B Entering TestWindowFactory.__del__: B (gdb) quit Notice that when the 'B' window replaces the 'A' window we see the 'A' object being deleted. But, when Python is shut down (after the 'quit') the 'B' object is never deleted. Instead, GDB retains a reference to the window factory object, which forces the Python object to remain live even after the Python interpreter itself has been shut down. The references themselves are held in a dynamically allocated std::unordered_map (in tui/tui-layout.c) which is never deallocated, thus the underlying Python references are never decremented to zero, and so GDB never tries to delete these Python objects. This commit is the first half of the work to clean up this edge case. All gdbpy_tui_window_maker objects (the objects that implement the TUI window factory callback for Python defined TUI windows), are now linked together into a global list using the intrusive list mechanism. When GDB shuts down the Python interpreter we can now walk this global list and release the reference that is held to the underlying Python object. By releasing this reference the Python object will now be deleted. I've added a new assert in gdbpy_tui_window_maker::operator(), this will catch the case where we somehow end up in here after having reset the reference to the underlying Python object. I don't think this should ever happen though as we only clear the references when shutting down the Python interpreter, and the ::operator() function is only called when trying to apply a new TUI layout - something that shouldn't happen while GDB itself is shutting down. This commit does not update the std::unordered_map in tui-layout.c, that will be done in the next commit. Reviewed-By: Tom Tromey <tom@tromey.com>
2023-01-19GDB: Allow arbitrary keywords in integer set commandsMaciej W. Rozycki1-19/+37
Rather than just `unlimited' allow the integer set commands (or command options) to define arbitrary keywords for the user to use, removing hardcoded arrangements for the `unlimited' keyword. Remove the confusingly named `var_zinteger', `var_zuinteger' and `var_zuinteger_unlimited' `set'/`show' command variable types redefining them in terms of `var_uinteger', `var_integer' and `var_pinteger', which have the range of [0;UINT_MAX], [INT_MIN;INT_MAX], and [0;INT_MAX] each. Following existing practice `var_pinteger' allows extra negative values to be used, however unlike `var_zuinteger_unlimited' any number of such values can be defined rather than just `-1'. The "p" in `var_pinteger' stands for "positive", for the lack of a more appropriate unambiguous letter, even though 0 obviously is not positive; "n" would be confusing as to whether it stands for "non-negative" or "negative". Add a new structure, `literal_def', the entries of which define extra keywords allowed for a command and numerical values they correspond to. Those values are not verified against the basic range supported by the underlying variable type, allowing extra values to be allowed outside that range, which may or may not be individually made visible to the user. An optional value translation is possible with the structure to follow the existing practice for some commands where user-entered 0 is internally translated to UINT_MAX or INT_MAX. Such translation can now be arbitrary. Literals defined by this structure are automatically used for completion as necessary. So for example: const literal_def integer_unlimited_literals[] = { { "unlimited", INT_MAX, 0 }, { nullptr } }; defines an extra `unlimited' keyword and a user-visible 0 value, both of which get translated to INT_MAX for the setting to be used with. Similarly: const literal_def zuinteger_unlimited_literals[] = { { "unlimited", -1, -1 }, { nullptr } }; defines the same keyword and a corresponding user-visible -1 value that is used for the requested setting. If the last member were omitted (or set to `{}') here, then only the keyword would be allowed for the user to enter and while -1 would still be used internally trying to enter it as a part of a command would result in an "integer -1 out of range" error. Use said error message in all cases (citing the invalid value requested) replacing "only -1 is allowed to set as unlimited" previously used for `var_zuinteger_unlimited' settings only rather than propagating it to `var_pinteger' type. It could only be used for the specific case where a single extra `unlimited' keyword was defined standing for -1 and the use of numeric equivalents is discouraged anyway as it is for historical reasons only that they expose GDB internals, confusingly different across variable types. Similarly update the "must be >= -1" Guile error message. Redefine Guile and Python parameter types in terms of the new variable types and interpret extra keywords as Scheme keywords and Python strings used to communicate corresponding parameter values. Do not add a new PARAM_INTEGER Guile parameter type, however do handle the `var_integer' variable type now, permitting existing parameters defined by GDB proper, such as `listsize', to be accessed from Scheme code. With these changes in place it should be trivial for a Scheme or Python programmer to expand the syntax of the `make-parameter' command and the `gdb.Parameter' class initializer to have arbitrary extra literals along with their internal representation supplied. Update the testsuite accordingly. Approved-By: Simon Marchi <simon.marchi@efficios.com>
2023-01-01Update copyright year range in header of all files managed by GDBJoel Brobecker1-1/+1
This commit is the result of running the gdb/copyright.py script, which automated the update of the copyright year range for all source files managed by the GDB project to be updated to include year 2023.
2022-12-15gdb: remove static buffer in command_line_inputSimon Marchi1-1/+1
[I sent this earlier today, but I don't see it in the archives. Resending it through a different computer / SMTP.] The use of the static buffer in command_line_input is becoming problematic, as explained here [1]. In short, with this patch [2] that attempt to fix a post-hook bug, when running gdb.base/commands.exp, we hit a case where we read a "define" command line from a script file using command_command_line_input. The command line is stored in command_line_input's static buffer. Inside the define command's execution, we read the lines inside the define using command_line_input, which overwrites the define command, in command_line_input's static buffer. After the execution of the define command, execute_command does a command look up to see if a post-hook is registered. For that, it uses a now stale pointer that used to point to the define command, in the static buffer, causing a use-after-free. Note that the pointer in execute_command points to the dynamically-allocated buffer help by the static buffer in command_line_input, not to the static object itself, hence why we see a use-after-free. Fix that by removing the static buffer. I initially changed command_line_input and other related functions to return an std::string, which is the obvious but naive solution. The thing is that some callees don't need to return an allocated string, so this this an unnecessary pessimization. I changed it to passing in a reference to an std::string buffer, which the callee can use if it needs to return dynamically-allocated content. It fills the buffer and returns a pointers to the C string inside. The callees that don't need to return dynamically-allocated content simply don't use it. So, it started with modifying command_line_input as described above, all the other changes derive directly from that. One slightly shady thing is in handle_line_of_input, where we now pass a pointer to an std::string's internal buffer to readline's history_value function, which takes a `char *`. I'm pretty sure that this function does not modify the input string, because I was able to change it (with enough massaging) to take a `const char *`. A subtle change is that we now clear a UI's line buffer using a SCOPE_EXIT in command_line_handler, after executing the command. This was previously done by this line in handle_line_of_input: /* We have a complete command line now. Prepare for the next command, but leave ownership of memory to the buffer . */ cmd_line_buffer->used_size = 0; I think the new way is clearer. [1] https://inbox.sourceware.org/gdb-patches/becb8438-81ef-8ad8-cc42-fcbfaea8cddd@simark.ca/ [2] https://inbox.sourceware.org/gdb-patches/20221213112241.621889-1-jan.vrany@labware.com/ Change-Id: I8fc89b1c69870c7fc7ad9c1705724bd493596300 Reviewed-By: Tom Tromey <tom@tromey.com>
2022-10-18gdb, python: use gdbarch_iterate_over_objfiles_in_search_orderMarkus Metzger1-5/+2
The implementation of gdb.lookup_objfile() iterates over all objfiles and compares their name or build id to the user-provided search string. This will cause problems when supporting linker namespaces as the first objfile in any namespace will be found. Instead, use gdbarch_iterate_over_objfiles_in_search_order to only consider the namespace of gdb.current_objfile() for the search, which defaults to the initial namespace when gdb.current_objfile() is None.
2022-07-28gdb/python: Add BreakpointLocation typeSimon Farre1-0/+1
PR python/18385 v7: This version addresses the issues pointed out by Tom. Added nullchecks for Python object creations. Changed from using PyLong_FromLong to the gdb_py-versions. Re-factored some code to make it look more cohesive. Also added the more safe Python reference count decrement PY_XDECREF, even though the BreakpointLocation type is never instantiated by the user (explicitly documented in the docs) decrementing < 0 is made impossible with the safe call. Tom pointed out that using the policy class explicitly to decrement a reference counted object was not the way to go, so this has instead been wrapped in a ref_ptr that handles that for us in blocpy_dealloc. Moved macro from py-internal to py-breakpoint.c. Renamed section at the bottom of commit message "Patch Description". v6: This version addresses the points Pedro gave in review to this patch. Added the attributes `function`, `fullname` and `thread_groups` as per request by Pedro with the argument that it more resembles the output of the MI-command "-break-list". Added documentation for these attributes. Cleaned up left overs from copy+paste in test suite, removed hard coding of line numbers where possible. Refactored some code to use more c++-y style range for loops wrt to breakpoint locations. Changed terminology, naming was very inconsistent. Used a variety of "parent", "owner". Now "owner" is the only term used, and the field in the gdb_breakpoint_location_object now also called "owner". v5: Changes in response to review by Tom Tromey: - Replaced manual INCREF/DECREF calls with gdbpy_ref ptrs in places where possible. - Fixed non-gdb style conforming formatting - Get parent of bploc increases ref count of parent. - moved bploc Python definition to py-breakpoint.c The INCREF of self in bppy_get_locations is due to the individual locations holding a reference to it's owner. This is decremented at de-alloc time. The reason why this needs to be here is, if the user writes for instance; py loc = gdb.breakpoints()[X].locations[Y] The breakpoint owner object is immediately going out of scope (GC'd/dealloced), and the location object requires it to be alive for as long as it is alive. Thanks for your review, Tom! v4: Fixed remaining doc issues as per request by Eli. v3: Rewritten commit message, shortened + reworded, added tests. Patch Description Currently, the Python API lacks the ability to query breakpoints for their installed locations, and subsequently, can't query any information about them, or enable/disable individual locations. This patch solves this by adding Python type gdb.BreakpointLocation. The type is never instantiated by the user of the Python API directly, but is produced by the gdb.Breakpoint.locations attribute returning a list of gdb.BreakpointLocation. gdb.Breakpoint.locations: The attribute for retrieving the currently installed breakpoint locations for gdb.Breakpoint. Matches behavior of the "info breakpoints" command in that it only returns the last known or currently inserted breakpoint locations. BreakpointLocation contains 7 attributes 6 read-only attributes: owner: location owner's Python companion object source: file path and line number tuple: (string, long) / None address: installed address of the location function: function name where location was set fullname: fullname where location was set thread_groups: thread groups (inferiors) where location was set. 1 writeable attribute: enabled: get/set enable/disable this location (bool) Access/calls to these, can all throw Python exceptions (documented in the online documentation), and that's due to the nature of how breakpoint locations can be invalidated "behind the scenes", either by them being removed from the original breakpoint or changed, like for instance when a new symbol file is loaded, at which point all breakpoint locations are re-created by GDB. Therefore this patch has chosen to be non-intrusive: it's up to the Python user to re-request the locations if they become invalid. Also there's event handlers that handle new object files etc, if a Python user is storing breakpoint locations in some larger state they've built up, refreshing the locations is easy and it only comes with runtime overhead when the Python user wants to use them. gdb.BreakpointLocation Python type struct "gdbpy_breakpoint_location_object" is found in python-internal.h Its definition, layout, methods and functions are found in the same file as gdb.Breakpoint (py-breakpoint.c) 1 change was also made to breakpoint.h/c to make it possible to enable and disable a bp_location* specifically, without having its LOC_NUM, as this number also can change arbitrarily behind the scenes. Updated docs & news file as per request. Testsuite: tests the .source attribute and the disabling of individual locations. Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=18385 Change-Id: I302c1c50a557ad59d5d18c88ca19014731d736b0
2022-07-25set/show python dont-write-bytecode fixesKevin Buettner1-7/+25
GDB uses the environment variable PYTHONDONTWRITEBYTECODE to determine whether or not to write the result of byte-compiling python modules when the "python dont-write-bytecode" setting is "auto". Simon noticed that GDB's implementation doesn't follow the Python documentation. At present, GDB only checks for the existence of this environment variable. That is not sufficient though. Regarding PYTHONDONTWRITEBYTECODE, this document... https://docs.python.org/3/using/cmdline.html ...says: If this is set to a non-empty string, Python won't try to write .pyc files on the import of source modules. This commit fixes GDB's handling of PYTHONDONTWRITEBYTECODE by adding an empty string check. This commit also corrects the set/show command documentation for "python dont-write-bytecode". The current doc was just a copy of that for set/show python ignore-environment. During his review of an earlier version of this patch, Eli Zaretskii asked that the help text that I proposed for "set/show python dont-write-bytecode" be expanded. I've done that in addition to clarifying the documentation of this option in the GDB manual.
2022-07-21[gdb/python] Fix typo in test_pythonTom de Vries1-1/+1
Fix typo in ref_output_0 variable in test_python. Tested by running the selftest on x86_64-linux with python 3.11.
2022-07-21[gdb/python] Fix python selftest with python 3.11Tom de Vries1-4/+7
With python 3.11 I noticed: ... $ gdb -q -batch -ex "maint selftest python" Running selftest python. Self test failed: self-test failed at gdb/python/python.c:2246 Ran 1 unit tests, 1 failed ... In more detail: ... (gdb) p output $5 = "Traceback (most recent call last):\n File \"<string>\", line 0, \ in <module>\nKeyboardInterrupt\n" (gdb) p ref_output $6 = "Traceback (most recent call last):\n File \"<string>\", line 1, \ in <module>\nKeyboardInterrupt\n" ... Fix this by also allowing line number 0. Tested on x86_64-linux. This should hopefully fix buildbot builder gdb-rawhide-x86_64.
2022-07-20Wrap python_write_bytecode with HAVE_PYTHON ifdefKevin Buettner1-0/+2
This commit fixes a build error on machines lacking python headers and/or libraries.
2022-07-20Handle Python 3.11 deprecation of PySys_SetPath and Py_SetProgramNameKevin Buettner1-18/+81
Python 3.11 deprecates PySys_SetPath and Py_SetProgramName. The PyConfig API replaces these and other functions. This commit uses the PyConfig API to provide equivalent functionality while also preserving support for older versions of Python, i.e. those before Python 3.8. A beta version of Python 3.11 is available in Fedora Rawhide. Both Fedora 35 and Fedora 36 use Python 3.10, while Fedora 34 still used Python 3.9. I've tested these changes on Fedora 34, Fedora 36, and rawhide, though complete testing was not possible on rawhide due to a kernel bug. That being the case, I decided to enable the newer PyConfig API by testing PY_VERSION_HEX against 0x030a0000. This corresponds to Python 3.10. We could try to use the PyConfig API for Python versions as early as 3.8, but I'm reluctant to do this as there may have been PyConfig related bugs in earlier versions which have since been fixed. Recent linux distributions should have support for Python 3.10. This should be more than adequate for testing the new Python initialization code in GDB. Information about the PyConfig API as well as the motivation behind deprecating the old interface can be found at these links: https://github.com/python/cpython/issues/88279 https://peps.python.org/pep-0587/ https://docs.python.org/3.11/c-api/init_config.html The v2 commit also addresses several problems that Simon found in the v1 version. In v1, I had used Py_DontWriteBytecodeFlag in the new initialization code, but Simon pointed out that this global configuration variable will be deprecated in Python 3.12. This version of the patch no longer uses Py_DontWriteBytecodeFlag in the new initialization code. Additionally, both Py_DontWriteBytecodeFlag and Py_IgnoreEnvironmentFlag will no longer be used when building GDB against Python 3.10 or higher. While it's true that both of these global configuration variables are deprecated in Python 3.12, it makes sense to disable their use for gdb builds against 3.10 and higher since those are the versions for which the PyConfig API is now being used by GDB. (The PyConfig API includes different mechanisms for making the same settings afforded by use of the soon-to-be deprecated global configuration variables.) Simon also noted that PyConfig_Clear() would not have be called for one of the failure paths. I've fixed that problem and also made the rest of the "bail out" code more direct. In particular, PyConfig_Clear() will always be called, both for success and failure. The v3 patch addresses some rebase conflicts related to module initialization . Commit 3acd9a692dd ("Make 'import gdb.events' work") uses PyImport_ExtendInittab instead of PyImport_AppendInittab. That commit also initializes a struct for each module to import. Both the initialization and the call to were moved ahead of the ifdefs to avoid having to replicate (at least some of) the code three times in various portions of the ifdefs. Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=28668 Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=29287
2022-07-15Expose current 'print' settings to PythonTom Tromey1-0/+4
PR python/17291 asks for access to the current print options. While I think this need is largely satisfied by the existence of Value.format_string, it seemed to me that a bit more could be done. First, while Value.format_string uses the user's settings, it does not react to temporary settings such as "print/x". This patch changes this. Second, there is no good way to examine the current settings (in particular the temporary ones in effect for just a single "print"). This patch adds this as well. Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=17291
2022-07-05Make 'import gdb.events' workTom Tromey1-4/+12
Pierre-Marie noticed that, while gdb.events is a Python module, it can't be imported. This patch changes how this module is created, so that it can be imported, while also ensuring that the module is always visible, just as it was in the past. This new approach required one non-obvious change -- when running gdb.base/warning.exp, where --data-directory is intentionally not found, the event registries can now be nullptr. Consequently, this patch probably also requires https://sourceware.org/pipermail/gdb-patches/2022-June/189796.html Note that this patch obsoletes https://sourceware.org/pipermail/gdb-patches/2022-June/189797.html
2022-06-17event_location -> location_specPedro Alves1-5/+5
Currently, GDB internally uses the term "location" for both the location specification the user input (linespec, explicit location, or an address location), and for actual resolved locations, like the breakpoint locations, or the result of decoding a location spec to SaLs. This is expecially confusing in the breakpoints module, as struct breakpoint has these two fields: breakpoint::location; breakpoint::loc; "location" is the location spec, and "loc" is the resolved locations. And then, we have a method called "locations()", which returns the resolved locations as range... The location spec type is presently called event_location: /* Location we used to set the breakpoint. */ event_location_up location; and it is described like this: /* The base class for all an event locations used to set a stop event in the inferior. */ struct event_location { and even that is incorrect... Location specs are used for finding actual locations in the program in scenarios that have nothing to do with stop events. E.g., "list" works with location specs. To clean all this confusion up, this patch renames "event_location" to "location_spec" throughout, and then all the variables that hold a location spec, they are renamed to include "spec" in their name, like e.g., "location" -> "locspec". Similarly, functions that work with location specs, and currently have just "location" in their name are renamed to include "spec" in their name too. Change-Id: I5814124798aa2b2003e79496e78f95c74e5eddca
2022-06-15Check for listeners in emit_exiting_eventTom Tromey1-0/+3
I noticed that emit_exiting_event does not check whether there are any listeners before creating the event object. All other event emitters do this, so this patch updates this one as well.
2022-06-15gdb/python: implement the print_insn extension language hookAndrew Burgess1-1/+2
This commit extends the Python API to include disassembler support. The motivation for this commit was to provide an API by which the user could write Python scripts that would augment the output of the disassembler. To achieve this I have followed the model of the existing libopcodes disassembler, that is, instructions are disassembled one by one. This does restrict the type of things that it is possible to do from a Python script, i.e. all additional output has to fit on a single line, but this was all I needed, and creating something more complex would, I think, require greater changes to how GDB's internal disassembler operates. The disassembler API is contained in the new gdb.disassembler module, which defines the following classes: DisassembleInfo Similar to libopcodes disassemble_info structure, has read-only properties: address, architecture, and progspace. And has methods: __init__, read_memory, and is_valid. Each time GDB wants an instruction disassembled, an instance of this class is passed to a user written disassembler function, by reading the properties, and calling the methods (and other support methods in the gdb.disassembler module) the user can perform and return the disassembly. Disassembler This is a base-class which user written disassemblers should inherit from. This base class provides base implementations of __init__ and __call__ which the user written disassembler should override. DisassemblerResult This class can be used to hold the result of a call to the disassembler, it's really just a wrapper around a string (the text of the disassembled instruction) and a length (in bytes). The user can return an instance of this class from Disassembler.__call__ to represent the newly disassembled instruction. The gdb.disassembler module also provides the following functions: register_disassembler This function registers an instance of a Disassembler sub-class as a disassembler, either for one specific architecture, or, as a global disassembler for all architectures. builtin_disassemble This provides access to GDB's builtin disassembler. A common use case that I see is augmenting the existing disassembler output. The user code can call this function to have GDB disassemble the instruction in the normal way. The user gets back a DisassemblerResult object, which they can then read in order to augment the disassembler output in any way they wish. This function also provides a mechanism to intercept the disassemblers reads of memory, thus the user can adjust what GDB sees when it is disassembling. The included documentation provides a more detailed description of the API. There is also a new CLI command added: maint info python-disassemblers This command is defined in the Python gdb.disassemblers module, and can be used to list the currently registered Python disassemblers.
2022-06-15gdb: add extension language print_insn hookAndrew Burgess1-0/+2
This commit is setup for the next commit. In the next commit I will add a Python API to intercept the print_insn calls within GDB, each print_insn call is responsible for disassembling, and printing one instruction. After the next commit it will be possible for a user to write Python code that either wraps around the existing disassembler, or even, in extreme situations, entirely replaces the existing disassembler. This commit does not add any new Python API. What this commit does is put the extension language framework in place for a print_insn hook. There's a new callback added to 'struct extension_language_ops', which is then filled in with nullptr for Python and Guile. Finally, in the disassembler, the code is restructured so that the new extension language function ext_lang_print_insn is called before we delegate to gdbarch_print_insn. After this, the next commit can focus entirely on providing a Python implementation of the new print_insn callback. There should be no user visible change after this commit.
2022-06-01Add gdb.current_language and gdb.Frame.languageTom Tromey1-0/+12
This adds the gdb.current_language function, which can be used to find the current language without (1) ever having the value "auto" or (2) having to parse the output of "show language". It also adds the gdb.Frame.language, which can be used to find the language of a given frame. This is normally preferable if one has a Frame object handy.
2022-04-20Replace symbol_symtab with symbol::symtabTom Tromey1-1/+1
This turns symbol_symtab into a method on symbol. It also replaces symbol_set_symtab with a method.
2022-03-29Unify gdb printf functionsTom Tromey1-16/+16
Now that filtered and unfiltered output can be treated identically, we can unify the printf family of functions. This is done under the name "gdb_printf". Most of this patch was written by script.
2022-03-23gdb/python: remove Python 2/3 compatibility macrosSimon Marchi1-13/+13
New in this version: - Rebase on master, fix a few more issues that appeared. python-internal.h contains a number of macros that helped make the code work with both Python 2 and 3. Remove them and adjust the code to use the Python 3 functions. Change-Id: I99a3d80067fb2d65de4f69f6473ba6ffd16efb2d
2022-03-23gdb/python: remove Python 2 supportSimon Marchi1-19/+0
New in this version: - Add a PY_MAJOR_VERSION check in configure.ac / AC_TRY_LIBPYTHON. If the user passes --with-python=python2, this will cause a configure failure saying that GDB only supports Python 3. Support for Python 2 is a maintenance burden for any patches touching Python support. Among others, the differences between Python 2 and 3 string and integer types are subtle. It requires a lot of effort and thinking to get something that behaves correctly on both. And that's if the author and reviewer of the patch even remember to test with Python 2. See this thread for an example: https://sourceware.org/pipermail/gdb-patches/2021-December/184260.html So, remove Python 2 support. Update the documentation to state that GDB can be built against Python 3 (as opposed to Python 2 or 3). Update all the spots that use: - sys.version_info - IS_PY3K - PY_MAJOR_VERSION - gdb_py_is_py3k ... to only keep the Python 3 portions and drop the use of some now-removed compatibility macros. I did not update the configure script more than just removing the explicit references to Python 2. We could maybe do more there, like check the Python version and reject it if that version is not supported. Otherwise (with this patch), things will only fail at compile time, so it won't really be clear to the user that they are trying to use an unsupported Python version. But I'm a bit lost in the configure code that checks for Python, so I kept that for later. Change-Id: I75b0f79c148afbe3c07ac664cfa9cade052c0c62
2022-03-22gdb/python: add gdb.format_address functionAndrew Burgess1-0/+108
Add a new function, gdb.format_address, which is a wrapper around GDB's print_address function. This method takes an address, and returns a string with the format: ADDRESS <SYMBOL+OFFSET> Where, ADDRESS is the original address, formatted as hexadecimal, SYMBOL is a symbol with an address lower than ADDRESS, and OFFSET is the offset from SYMBOL to ADDRESS in decimal. If there's no SYMBOL suitably close to ADDRESS then the <SYMBOL+OFFSET> part is not included. This is useful if a user wants to write a Python script that pretty-prints addresses, the user no longer needs to do manual symbol lookup, or worry about correctly formatting addresses. Additionally, there are some settings that effect how GDB picks SYMBOL, and whether the file name and line number should be included with the SYMBOL name, the gdb.format_address function ensures that the users Python script also benefits from these settings. The gdb.format_address by default selects SYMBOL from the current inferiors program space, and address is formatted using the architecture for the current inferior. However, a user can also explicitly pass a program space and architecture like this: gdb.format_address(ADDRESS, PROGRAM_SPACE, ARCHITECTURE) In order to format an address for a different inferior. Notes on the implementation: In py-arch.c I extended arch_object_to_gdbarch to add an assertion for the type of the PyObject being worked on. Prior to this commit all uses of arch_object_to_gdbarch were guaranteed to pass this function a gdb.Architecture object, but, with this commit, this might not be the case. So, with this commit I've made it a requirement that the PyObject be a gdb.Architecture, and this is checked with the assert. And in order that callers from other files can check if they have a gdb.Architecture object, I've added the new function gdbpy_is_architecture. In py-progspace.c I've added two new function, the first progspace_object_to_program_space, converts a PyObject of type gdb.Progspace to the associated program_space pointer, and gdbpy_is_progspace checks if a PyObject is a gdb.Progspace or not.
2022-03-18gdb/python: remove gdb._mi_commands dictSimon Marchi1-0/+2
The motivation for this patch is the fact that py-micmd.c doesn't build with Python 2, due to PyDict_GetItemWithError being a Python 3-only function: CXX python/py-micmd.o /home/smarchi/src/binutils-gdb/gdb/python/py-micmd.c: In function ‘int micmdpy_uninstall_command(micmdpy_object*)’: /home/smarchi/src/binutils-gdb/gdb/python/py-micmd.c:430:20: error: ‘PyDict_GetItemWithError’ was not declared in this scope; did you mean ‘PyDict_GetItemString’? 430 | PyObject *curr = PyDict_GetItemWithError (mi_cmd_dict.get (), | ^~~~~~~~~~~~~~~~~~~~~~~ | PyDict_GetItemString A first solution to fix this would be to try to replace PyDict_GetItemWithError equivalent Python 2 code. But I looked at why we are doing this in the first place: it is to maintain the `gdb._mi_commands` Python dictionary that we use as a `name -> gdb.MICommand object` map. Since the `gdb._mi_commands` dictionary is never actually used in Python, it seems like a lot of trouble to use a Python object for this. My first idea was to replace it with a C++ map (std::unordered_map<std::string, gdbpy_ref<micmdpy_object>>). While implementing this, I realized we don't really need this map at all. The mi_command_py objects registered in the main MI command table can own their backing micmdpy_object (that's a gdb.MICommand, but seen from the C++ code). To know whether an mi_command is an mi_command_py, we can use a dynamic cast. Since there's one less data structure to maintain, there are less chances of messing things up. - Change mi_command_py::m_pyobj to a gdbpy_ref, the mi_command_py is now what keeps the MICommand alive. - Set micmdpy_object::mi_command in the constructor of mi_command_py. If mi_command_py manages setting/clearing that field in swap_python_object, I think it makes sense that it also takes care of setting it initially. - Move a bunch of checks from micmdpy_install_command to swap_python_object, and make them gdb_asserts. - In micmdpy_install_command, start by doing an mi_cmd_lookup. This is needed to know whether there's a Python MI command already registered with that name. But we can already tell if there's a non-Python command registered with that name. Return an error if that happens, rather than waiting for insert_mi_cmd_entry to fail. Change the error message to "name is already in use" rather than "may already be in use", since it's more precise. I asked Andrew about the original intent of using a Python dictionary object to hold the command objects. The reason was to make sure the objects get destroyed when the Python runtime gets finalized, not later. Holding the objects in global C++ data structures and not doing anything more means that the held Python objects will be decref'd after the Python interpreter has been finalized. That's not desirable. I tried it and it indeed segfaults. Handle this by adding a gdbpy_finalize_micommands function called in finalize_python. This is the mirror of gdbpy_initialize_micommands called in do_start_initialization. In there, delete all Python MI commands. I think it makes sense to do it this way: if it was somehow possible to unload Python support from GDB in the middle of a session we'd want to unregister any Python MI command. Otherwise, these MI commands would be backed with a stale PyObject or simply nothing. Delete tests that were related to `gdb._mi_commands`. Co-Authored-By: Andrew Burgess <aburgess@redhat.com> Change-Id: I060d5ebc7a096c67487998a8a4ca1e8e56f12cd3
2022-03-14gdb/python/mi: create MI commands using pythonAndrew Burgess1-1/+2
This commit allows a user to create custom MI commands using Python similarly to what is possible for Python CLI commands. A new subclass of mi_command is defined for Python MI commands, mi_command_py. A new file, gdb/python/py-micmd.c contains the logic for Python MI commands. This commit is based on work linked too from this mailing list thread: https://sourceware.org/pipermail/gdb/2021-November/049774.html Which has also been previously posted to the mailing list here: https://sourceware.org/pipermail/gdb-patches/2019-May/158010.html And was recently reposted here: https://sourceware.org/pipermail/gdb-patches/2022-January/185190.html The version in this patch takes some core code from the previously posted patches, but also has some significant differences, especially after the feedback given here: https://sourceware.org/pipermail/gdb-patches/2022-February/185767.html A new MI command can be implemented in Python like this: class echo_args(gdb.MICommand): def invoke(self, args): return { 'args': args } echo_args("-echo-args") The 'args' parameter (to the invoke method) is a list containing (almost) all command line arguments passed to the MI command (--thread and --frame are handled before the Python code is called, and removed from the args list). This list can be empty if the MI command was passed no arguments. When used within gdb the above command produced output like this: (gdb) -echo-args a b c ^done,args=["a","b","c"] (gdb) The 'invoke' method of the new command must return a dictionary. The keys of this dictionary are then used as the field names in the mi command output (e.g. 'args' in the above). The values of the result returned by invoke can be dictionaries, lists, iterators, or an object that can be converted to a string. These are processed recursively to create the mi output. And so, this is valid: class new_command(gdb.MICommand): def invoke(self,args): return { 'result_one': { 'abc': 123, 'def': 'Hello' }, 'result_two': [ { 'a': 1, 'b': 2 }, { 'c': 3, 'd': 4 } ] } Which produces output like: (gdb) -new-command ^done,result_one={abc="123",def="Hello"},result_two=[{a="1",b="2"},{c="3",d="4"}] (gdb) I have required that the fields names used in mi result output must match the regexp: "^[a-zA-Z][-_a-zA-Z0-9]*$" (without the quotes). This restriction was never written down anywhere before, but seems sensible to me, and we can always loosen this rule later if it proves to be a problem. Much harder to try and add a restriction later, once people are already using the API. What follows are some details about how this implementation differs from the original patch that was posted to the mailing list. In this patch, I have changed how the lifetime of the Python gdb.MICommand objects is managed. In the original patch, these object were kept alive by an owned reference within the mi_command_py object. As such, the Python object would not be deleted until the mi_command_py object itself was deleted. This caused a problem, the mi_command_py were held in the global mi command table (in mi/mi-cmds.c), which, as a global, was not cleared until program shutdown. By this point the Python interpreter has already been shutdown. Attempting to delete the mi_command_py object at this point was causing GDB to try and invoke Python code after finalising the Python interpreter, and we would crash. To work around this problem, the original patch added code in python/python.c that would search the mi command table, and delete the mi_command_py objects before the Python environment was finalised. In contrast, in this patch, I have added a new global dictionary to the gdb module, gdb._mi_commands. We already have several such global data stores related to pretty printers, and frame unwinders. The MICommand objects are placed into the new gdb.mi_commands dictionary, and it is this reference that keeps the objects alive. When GDB's Python interpreter is shut down gdb._mi_commands is deleted, and any MICommand objects within it are deleted at this point. This change avoids having to make the mi_cmd_table global, and walk over it from within GDB's python related code. This patch handles command redefinition entirely within GDB's python code, though this does impose one small restriction which is not present in the original code (detailed below), I don't think this is a big issue. However, the original patch relied on being able to finish executing the mi_command::do_invoke member function after the mi_command object had been deleted. Though continuing to execute a member function after an object is deleted is well defined, it is also (IMHO) risky, its too easy for someone to later add a use of the object without realising that the object might sometimes, have been deleted. The new patch avoids this issue. The one restriction that is added to avoid this, is that an MICommand object can't be reinitialised with a different command name, so: (gdb) python cmd = MyMICommand("-abc") (gdb) python cmd.__init__("-def") can't reinitialize object with a different command name This feels like a pretty weird edge case, and I'm happy to live with this restriction. I have also changed how the memory is managed for the command name. In the most recently posted patch series, the command name is moved into a subclass of mi_command, the python mi_command_py, which inherits from mi_command is then free to use a smart pointer to manage the memory for the name. In this patch, I leave the mi_command class unchanged, and instead hold the memory for the name within the Python object, as the lifetime of the Python object always exceeds the c++ object stored in the mi_cmd_table. This adds a little more complexity in py-micmd.c, but leaves the mi_command class nice and simple. Next, this patch adds some extra functionality, there's a MICommand.name read-only attribute containing the name of the command, and a read-write MICommand.installed attribute that can be used to install (make the command available for use) and uninstall (remove the command from the mi_cmd_table so it can't be used) the command. This attribute will be automatically updated if a second command replaces an earlier command. This patch adds additional error handling, and makes more use the gdbpy_handle_exception function. Co-Authored-By: Jan Vrany <jan.vrany@labware.com>
2022-02-14gdb/python: move styling support to gdb.stylingAndrew Burgess1-6/+18
This commit moves the two Python functions that are used for styling into a new module, gdb.styling, there's then a small update in python.c so GDB can find the functions in their new location. The motivation for this change is purely to try and reduce the clutter in the top-level gdb module, and encapsulate related functions into modules. I did ponder documenting these functions as part of the Python API, however, doing so would effectively "fix" the API, and I'm still wondering if there's improvements that could be made, also, the colorize function is only called in some cases now that GDB prefers libsource-highlight, so it's not entirely sure how this would work as part of a user facing API. Still, despite these functions never having been part of a documented API, it is possible that a user out there has overridden these to, in some way, customize how GDB performs styling. Moving the function as I propose in this patch could break things for that user, however, fixing this breakage is trivial, and, as these functions were never documented, I don't think we should be obliged to not break user code that relies on them.
2022-02-14gdb: use python to colorize disassembler outputAndrew Burgess1-0/+67
This commit adds styling support to the disassembler output, as such two new commands are added to GDB: set style disassembler enabled on|off show style disassembler enabled In this commit I make use of the Python Pygments package to provide the styling. I did investigate making use of libsource-highlight, however, I found the highlighting results to be inferior to those of Pygments; only some mnemonics were highlighted, and highlighting of register names such as r9d and r8d (on x86-64) was incorrect. To enable disassembler highlighting via Pygments, I've added a new extension language hook, which is then implemented for Python. This hook is very similar to the existing hook for source code colorization. One possibly odd choice I made with the new hook is to pass a gdb.Architecture through, even though this is currently unused. The reason this argument is not used is that, currently, styling is performed identically for all architectures. However, even though the Python function used to perform styling of disassembly output is not part of any documented API, I don't want to close the door on a user overriding this function to provide architecture specific styling. To do this, the user would inevitably require access to the gdb.Architecture, and so I decided to add this field now. The styling is applied within gdb_disassembler::print_insn, to achieve this, gdb_disassembler now writes its output into a temporary buffer, styling is then applied to the contents of this buffer. Finally the gdb_disassembler buffer is copied out to its final destination stream. There's a new test to check that the disassembler output includes some escape sequences, though I don't check for specific colours; the precise colors will depend on which instructions are in the disassembler output, and, I guess, how pygments is configured. The only negative change with this commit is how we currently style addresses in GDB. Currently, when the disassembler wants to print an address, we call back into GDB, and GDB prints the address value using the `address` styling, and the symbol name using `function` styling. After this commit, if pygments is used, then all disassembler styling is done through pygments, and this include the address and symbol name parts of the disassembler output. I don't know how much of an issue this will be for people. There's already some precedent for this in GDB when we look at source styling. For example, function names in styled source listings are not styled using the `function` style, but instead, either GNU Source Highlight, or pygments gets to decide how the function name should be styled. If the Python pygments library is not present then GDB will continue to behave as it always has, the disassembler output is mostly unstyled, but the address and symbols are styled using the `address` and `function` styles, as they are today. However, if the user does `set style disassembler enabled off`, then all disassembler styling is switched off. This obviously covers the use of pygments, but also includes the minimal styling done by GDB when pygments is not available.
2022-01-26gdb/python: handle non utf-8 characters when source highlightingAndrew Burgess1-14/+17
This commit adds support for source files that contain non utf-8 characters when performing source styling using the Python pygments package. This does not change the behaviour of GDB when the GNU Source Highlight library is used. For the following problem description, assume that either GDB is built without GNU Source Highlight support, of that this has been disabled using 'maintenance set gnu-source-highlight enabled off'. The initial problem reported was that a source file containing non utf-8 characters would cause GDB to print a Python exception, and then display the source without styling, e.g.: Python Exception <class 'UnicodeDecodeError'>: 'utf-8' codec can't decode byte 0xc0 in position 142: invalid start byte /* Source code here, without styling... */ Further, as the user steps through different source files, each time the problematic source file was evicted from the source cache, and then later reloaded, the exception would be printed again. Finally, this problem is only present when using Python 3, this issue is not present for Python 2. What makes this especially frustrating is that GDB can clearly print the source file contents, they're right there... If we disable styling completely, or make use of the GNU Source Highlight library, then everything is fine. So why is there an error when we try to apply styling using Python? The problem is the use of PyString_FromString (which is an alias for PyUnicode_FromString in Python 3), this function converts a C string into a either a Unicode object (Py3) or a str object (Py2). For Python 2 there is no unicode encoding performed during this function call, but for Python 3 the input is assumed to be a uft-8 encoding string for the purpose of the conversion. And here of course, is the problem, if the source file contains non utf-8 characters, then it should not be treated as utf-8, but that's what we do, and that's why we get an error. My first thought when looking at this was to spot when the PyString_FromString call failed with a UnicodeDecodeError and silently ignore the error. This would mean that GDB would print the source without styling, but would also avoid the annoying exception message. However, I also make use of `pygmentize`, a command line wrapper around the Python pygments module, which I use to apply syntax highlighting in the output of `less`. And this command line wrapper is quite happy to syntax highlight my source file that contains non utf-8 characters, so it feels like the problem should be solvable. It turns out that inside the pygments module there is already support for guessing the encoding of the incoming file content, if the incoming content is not already a Unicode string. This is what happens for Python 2 where the incoming content is of `str` type. We could try and make GDB smarter when it comes to converting C strings into Python Unicode objects; this would probably require us to just try a couple of different encoding schemes rather than just giving up after utf-8. However, I figure, why bother? The pygments module already does this for us, and the colorize API is not part of the documented external API of GDB. So, why not just change the colorize API, instead of the content being a Unicode string (for Python 3), lets just make the content be a bytes object. The pygments module can then take responsibility for guessing the encoding. So, currently, the colorize API receives a unicode object, and returns a unicode object. I propose that the colorize API receive a bytes object, and return a bytes object.
2022-01-26gdb/python: add gdb.history_count functionAndrew Burgess1-0/+2
Add a new function gdb.history_count to the Python api, this function returns an integer, the number of items in GDB's value history. This is useful if you want to pull items from the history by their absolute number, for example, if you wanted to show a complete history list. Previously we could figure out how many items are in the history list by trying to fetch the items, and then catching the exception when the item is not available, but having this function seems nicer.
2022-01-26Change how Python architecture and language are handledTom Tromey1-24/+38
Currently, gdb's Python layer captures the current architecture and language when "entering" Python code. This has some undesirable effects, and so this series changes how this is handled. First, there is code like this: gdbpy_enter enter_py (python_gdbarch, python_language); This is incorrect, because both of these are NULL when not otherwise assigned. This can cause crashes in some cases -- I've added one to the test suite. (Note that this crasher is just an example, other ones along the same lines are possible.) Second, when the language is captured in this way, it means that Python code cannot affect the current language for its own purposes. It's reasonable to want to write code like this: gdb.execute('set language mumble') ... stuff using the current language gdb.execute('set language previous-value') However, this won't actually work, because the language is captured on entry. I've added a test to show this as well. This patch changes gdb to try to avoid capturing the current values. The Python concept of the current gdbarch is only set in those few cases where a non-default value is computed or needed; and the language is not captured at all -- instead, in the cases where it's required, the current language is temporarily changed.
2022-01-12gdb/python: add gdb.host_charset functionAndrew Burgess1-0/+13
We already have gdb.target_charset and gdb.target_wide_charset. This commit adds gdb.host_charset along the same lines.
2022-01-01Automatic Copyright Year update after running gdb/copyright.pyJoel Brobecker1-1/+1
This commit brings all the changes made by running gdb/copyright.py as per GDB's Start of New Year Procedure. For the avoidance of doubt, all changes in this commits were performed by the script.
2021-11-30gdb/python: introduce gdb.TargetConnection object typeAndrew Burgess1-0/+5
This commit adds a new object type gdb.TargetConnection. This new type represents a connection within GDB (a connection as displayed by 'info connections'). There's three ways to find a gdb.TargetConnection, there's a new 'gdb.connections()' function, which returns a list of all currently active connections. Or you can read the new 'connection' property on the gdb.Inferior object type, this contains the connection for that inferior (or None if the inferior has no connection, for example, it is exited). Finally, there's a new gdb.events.connection_removed event registry, this emits a new gdb.ConnectionEvent whenever a connection is removed from GDB (this can happen when all inferiors using a connection exit, though this is not always the case, depending on the connection type). The gdb.ConnectionEvent has a 'connection' property, which is the gdb.TargetConnection being removed from GDB. The gdb.TargetConnection has an 'is_valid()' method. A connection object becomes invalid when the underlying connection is removed from GDB (as discussed above, this might be when all inferiors using a connection exit, or it might be when the user explicitly replaces a connection in GDB by issuing another 'target' command). The gdb.TargetConnection has the following read-only properties: 'num': The number for this connection, 'type': e.g. 'native', 'remote', 'sim', etc 'description': The longer description as seen in the 'info connections' command output. 'details': A string or None. Extra details for the connection, for example, a remote connection's details might be 'hostname:port'.
2021-11-25gdb: ensure extension_language_python is always definedEnze Li1-0/+4
In this commit: commit c6a6aad52d9e839d6a84ac31cabe2b7e1a2a31a0 Date: Mon Oct 25 17:25:45 2021 +0100 gdb/python: make some global variables static building without Python was broken. The extension_language_python global was moved from being always defined, to only being defined when the HAVE_PYTHON macro was defined. As a consequence, building without Python support would result in errors like: /usr/bin/ld: extension.o:(.rodata+0x120): undefined reference to `extension_language_python' This commit fixes the problem by moving the definition of extension_language_python outside of the HAVE_PYTHON macro protection.
2021-11-25gdb/python: make some global variables staticAndrew Burgess1-29/+24
Make a couple of global variables static in python/python.c. To do this I had to move the definition of extension_language_python to later in the file. There should be no user visible changes after this commit.
2021-10-28gdb: add add_setshow_prefix_cmdSimon Marchi1-7/+5
There's a common pattern to call add_basic_prefix_cmd and add_show_prefix_cmd to add matching set and show commands. Add the add_setshow_prefix_cmd function to factor that out and use it at a few places. Change-Id: I6e9e90a30e9efb7b255bf839cac27b85d7069cfd
2021-10-22gdb/python: move gdb.Membuf support into a new fileAndrew Burgess1-0/+1
In a future commit I'm going to be creating gdb.Membuf objects from a new file within gdb/python/py*.c. Currently all gdb.Membuf objects are created directly within infpy_read_memory (as a result of calling gdb.Inferior.read_memory()). Initially I split out the Membuf creation code into a new function, and left the new function in gdb/python/py-inferior.c, however, it felt a little random that the Membuf creation code should live with the inferior handling code. So, then I moved all of the Membuf related code out into a new file, gdb/python/py-membuf.c, the interface is gdbpy_buffer_to_membuf, which wraps an array of bytes into a gdb.Membuf object. Most of the code is moved directly from py-inferior.c with only minor tweaks to layout and replacing NULL with nullptr, hence, I've left the copyright date on py-membuf.c as 2009-2021 to match py-inferior.c. Currently, the only user of this code is still py-inferior.c, but in later commits this will change. There should be no user visible changes after this commit.
2021-10-22gdb/python: new gdb.architecture_names functionAndrew Burgess1-0/+4
Add a new function to the Python API, gdb.architecture_names(). This function returns a list containing all of the supported architecture names within the current build of GDB. The values returned in this list are all of the possible values that can be returned from gdb.Architecture.name().
2021-10-19[gdb/testsuite] Reimplement gdb.gdb/python-interrupts.exp as unittestTom de Vries1-15/+40
The test-case gdb.gdb/python-interrupts.exp: - runs to captured_command_loop - sets a breakpoint at set_active_ext_lang - calls a python command - verifies the command triggers the breakpoint - sends a signal and verifies the result The test-case is fragile, because (f.i. with -flto) it cannot be guaranteed that captured_command_loop and set_active_ext_lang are available for setting breakpoints. Reimplement the test-case as unittest, using: - execute_command_to_string to capture the output - try/catch to catch the "Error while executing Python code" exception - a new hook selftests::hook_set_active_ext_lang to raise the signal Tested on x86_64-linux.
2021-10-09[gdb] Make execute_command_to_string return string on throwTom de Vries1-3/+3
The pattern for using execute_command_to_string is: ... std::string output; output = execute_fn_to_string (fn, term_out); ... This results in a problem when using it in a try/catch: ... try { output = execute_fn_to_string (fn, term_out) } catch (const gdb_exception &e) { /* Use output. */ } ... If an expection was thrown during execute_fn_to_string, then the output remains unassigned, while it could be worthwhile to known what output was generated by gdb before the expection was thrown. Fix this by returning the string using a parameter instead: ... execute_fn_to_string (output, fn, term_out) ... Also add a variant without string parameter, to support places where the function is used while ignoring the result: ... execute_fn_to_string (fn, term_out) ... Tested on x86_64-linux.
2021-10-05gdb/python: add a new gdb_exiting eventAndrew Burgess1-0/+35
Add a new event, gdb.events.gdb_exiting, which is called once GDB decides it is going to exit. This event is not triggered in the case that GDB performs a hard abort, for example, when handling an internal error and the user decides to quit the debug session, or if GDB hits an unexpected, fatal, signal. This event is triggered if the user just types 'quit' at the command prompt, or if GDB is run with '-batch' and has processed all of the required commands. The new event type is gdb.GdbExitingEvent, and it has a single attribute exit_code, which is the value that GDB is about to exit with. The event is triggered before GDB starts dismantling any of its own internal state, so, my expectation is that most Python calls should work just fine at this point. When considering this functionality I wondered about using the 'atexit' Python module. However, this is triggered when the Python environment is shut down, which is done from a final cleanup. At this point we don't know for sure what other GDB state has already been cleaned up.