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2024-01-12Update copyright year range in header of all files managed by GDBAndrew Burgess1-1/+1
This commit is the result of the following actions: - Running gdb/copyright.py to update all of the copyright headers to include 2024, - Manually updating a few files the copyright.py script told me to update, these files had copyright headers embedded within the file, - Regenerating gdbsupport/Makefile.in to refresh it's copyright date, - Using grep to find other files that still mentioned 2023. If these files were updated last year from 2022 to 2023 then I've updated them this year to 2024. I'm sure I've probably missed some dates. Feel free to fix them up as you spot them.
2023-11-28gdb/python: display errors from command completionAndrew Burgess1-0/+30
This commit makes the gdb.Command.complete methods more verbose when it comes to error handling. Previous to this commit if any commands implemented in Python implemented the complete method, and if there were any errors encountered when calling that complete method, then GDB would silently hide the error and continue as if there were no completions. This makes is difficult to debug any errors encountered when writing completion methods, and encourages the idea that Python extensions can be broken, and GDB will just silently work around them. I don't think this is a good idea. GDB should encourage extensions to be written correctly, and robustly, and one way in which GDB can (I think) support this, is by pointing out when an extension goes wrong. In this commit I've gone through the Python command completion code, and added calls to gdbpy_print_stack() or gdbpy_print_stack_or_quit() in places where we were either clearing the Python error, or, in some cases, just not handling the error at all. One thing I have not changed is in cmdpy_completer (py-cmd.c) where we process the list of completions returned from the Command.complete method; this routine includes a call to gdbpy_is_string to check a possible completion is a string, if not the completion is ignored. I was tempted to remove this check, attempt to complete each result to a string, and display an error if the conversion fails. After all, returning anything but a string is surely a mistake by the extension author. However, the docs clearly say that only strings within the returned list will be considered as completions. Anything else is ignored. As such, and to avoid (what I think is pretty unlikely) breakage of existing code, I've retained the gdbpy_is_string check. After the gdbpy_is_string check we call python_string_to_host_string, if this call fails then I do now print the error, where before we ignored the error. I think this is OK; if GDB thinks something is a string, but still can't convert it to a string, then I think it's OK to display the error in that case. Another case which I was a little unsure about was in cmdpy_completer_helper, and the call to PyObject_CallMethodObjArgs, which is when we actually call Command.complete. Previously, if this call resulted in an exception then we would ignore this and just pretend there were no completions. Of all the changes, this is possibly the one with the biggest potential for breaking existing scripts, but also, is, I think, the most useful change. If the user code is wrong in some way, such that an exception is raised, then previously the user would have no obvious feedback about this breakage. Now GDB will print the exception for them, making it, I think, much easier to debug their extension. But, if there is user code in the wild that relies on raising an exception as a means to indicate there are no completions .... well, that code is going to break after this commit. I think we can live with this though, the exceptions means no completions thing was never documented behaviour. I also added a new error() call if the PyObject_CallMethodObjArgs call raises an exception. This causes the completion mechanism within GDB to stop. Within GDB the completion code is called twice, the first time to compute the work break characters, and then a second time to compute the actual completions. If PyObject_CallMethodObjArgs raises an exception when computing the word break character, and we print it by calling gdbpy_print_stack_or_quit(), but then carry on as if PyObject_CallMethodObjArgs had returns no completions, GDB will call the Python completion code again, which results in another call to PyObject_CallMethodObjArgs, which might raise the same exception again. This results in the Python exception being printed twice. By throwing a C++ exception after the failed PyObject_CallMethodObjArgs call, the completion mechanism is aborted, and no completions are offered. But importantly, the Python exception is only printed once. I think this gives a much better user experience. I've added some tests to cover this case, as I think this is the most likely case that a user will run into. Approved-By: Tom Tromey <tom@tromey.com>
2023-11-27gdb/python: handle completion returning a non-sequenceAndrew Burgess1-0/+12
GDB's Python API documentation for gdb.Command.complete() says: The 'complete' method can return several values: * If the return value is a sequence, the contents of the sequence are used as the completions. It is up to 'complete' to ensure that the contents actually do complete the word. A zero-length sequence is allowed, it means that there were no completions available. Only string elements of the sequence are used; other elements in the sequence are ignored. * If the return value is one of the 'COMPLETE_' constants defined below, then the corresponding GDB-internal completion function is invoked, and its result is used. * All other results are treated as though there were no available completions. So, returning a non-sequence, and non-integer from a complete method should be fine; it should just be treated as though there are no completions. However, if I write a complete method that returns None, I see this behaviour: (gdb) complete completefilenone x Python Exception <class 'TypeError'>: 'NoneType' object is not iterable warning: internal error: Unhandled Python exception (gdb) Which is caused because we currently assume that anything that is not an integer must be iterable, and we call PyObject_GetIter on it. When this call fails a Python exception is set, but instead of clearing (and therefore ignoring) this exception as we do everywhere else in the Python completion code, we instead just return with the exception set. In this commit I add a PySequence_Check call. If this call returns false (and we've already checked the integer case) then we can assume there are no completion results. I've added a test which checks returning a non-sequence. Approved-By: Tom Tromey <tom@tromey.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.
2022-01-01Automatic 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.
2021-05-07gdb: re-format Python files using black 21.4b0Simon Marchi1-87/+154
Re-format all Python files using black [1] version 21.4b0. The goal is that from now on, we keep all Python files formatted using black. And that we never have to discuss formatting during review (for these files at least) ever again. One change is needed in gdb.python/py-prettyprint.exp, because it matches the string representation of an exception, which shows source code. So the change in formatting must be replicated in the expected regexp. To document our usage of black I plan on adding this to the "GDB Python Coding Standards" wiki page [2]: --8<-- All Python source files under the `gdb/` directory must be formatted using black version 21.4b0. This specific version can be installed using: $ pip3 install 'black == 21.4b0' All you need to do to re-format files is run `black <file/directory>`, and black will re-format any Python file it finds in there. It runs quite fast, so the simplest is to do: $ black gdb/ from the top-level. If you notice that black produces changes unrelated to your patch, it's probably because someone forgot to run it before you. In this case, don't include unrelated hunks in your patch. Push an obvious patch fixing the formatting and rebase your work on top of that. -->8-- Once this is merged, I plan on setting a up an `ignoreRevsFile` config so that git-blame ignores this commit, as described here: https://github.com/psf/black#migrating-your-code-style-without-ruining-git-blame I also plan on working on a git commit hook (checked in the repo) to automatically check the formatting of the Python files on commit. [1] https://pypi.org/project/black/ [2] https://sourceware.org/gdb/wiki/Internals%20GDB-Python-Coding-Standards gdb/ChangeLog: * Re-format all Python files using black. gdb/testsuite/ChangeLog: * Re-format all Python files using black. * gdb.python/py-prettyprint.exp (run_lang_tests): Adjust. Change-Id: I28588a22c2406afd6bc2703774ddfff47cd61919
2021-01-01Update copyright year range in all GDB filesJoel Brobecker1-1/+1
This commits the result of running gdb/copyright.py as per our Start of New Year procedure... gdb/ChangeLog Update copyright year range in copyright header of all GDB files.
2020-01-01Update copyright year range in all GDB files.Joel Brobecker1-1/+1
gdb/ChangeLog: Update copyright year range in all GDB files.
2019-01-01Update copyright year range in all GDB files.Joel Brobecker1-1/+1
This commit applies all changes made after running the gdb/copyright.py script. Note that one file was flagged by the script, due to an invalid copyright header (gdb/unittests/basic_string_view/element_access/char/empty.cc). As the file was copied from GCC's libstdc++-v3 testsuite, this commit leaves this file untouched for the time being; a patch to fix the header was sent to gcc-patches first. gdb/ChangeLog: Update copyright year range in all GDB files.
2018-01-02Update copyright year range in all GDB filesJoel Brobecker1-1/+1
gdb/ChangeLog: Update copyright year range in all GDB files
2017-01-01update copyright year range in GDB filesJoel Brobecker1-1/+1
This applies the second part of GDB's End of Year Procedure, which updates the copyright year range in all of GDB's files. gdb/ChangeLog: Update copyright year range in all GDB files.
2016-01-01GDB copyright headers update after running GDB's copyright.py script.Joel Brobecker1-1/+1
gdb/ChangeLog: Update year range in copyright notice of all files.
2015-04-08Fix Python completion when using the "complete" commandSergio Durigan Junior1-0/+89
This patch is related to PR python/16699, and is an improvement over the patch posted here: <https://sourceware.org/ml/gdb-patches/2014-03/msg00301.html> Keith noticed that, when using the "complete" command on GDB to complete a Python command, some strange things could happen. In order to understand what can go wrong, I need to explain how the Python completion mechanism works. When the user requests a completion of a Python command by using TAB, GDB will first try to determine the right set of "brkchars" that will be used when doing the completion. This is done by actually calling the "complete" method of the Python class. Then, when we already know the "brkchars" that will be used, we call the "complete" method again, for the same values. If you read the thread mentioned above, you will see that one of the design decisions was to make the "cmdpy_completer_helper" (which is the function the does the actual calling of the "complete" method) cache the first result of the completion, since this result will be used in the second call, to do the actual completion. The problem is that the "complete" command does not process the brkchars, and the current Python completion mechanism (improved by the patch mentioned above) relies on GDB trying to determine the brkchars, and then doing the completion itself. Therefore, when we use the "complete" command instead of doing a TAB-completion on GDB, there is a scenario where we can use the invalid cache of a previous Python command that was completed before. For example: (gdb) A <TAB> (gdb) complete B B value1 B value10 B value2 B value3 B value4 B value5 B value6 B value7 B value8 B value9 (gdb) B <TAB> comp1 comp2 comp4 comp6 comp8 comp10 comp3 comp5 comp7 comp9 Here, we see that "complete B " gave a different result than "B <TAB>". The reason for that is because "A <TAB>" was called before, and its completion results were "value*", so when GDB tried to "complete B " it wrongly answered with the results for A. The problem here is using a wrong cache (A's cache) for completing B. We tried to come up with a solution that would preserve the caching mechanism, but it wasn't really possible. So I decided to completely remove the cache, and doing the method calling twice for every completion. This is not optimal, but I do not think it will impact users noticeably. It is worth mentioning another small issue that I found. The code was doing: wordobj = PyUnicode_Decode (word, sizeof (word), host_charset (), NULL); which is totally wrong, because using "sizeof" here will lead to always the same result. So I changed this to use "strlen". The testcase also catches this problem. Keith kindly expanded the existing testcase to cover the problem described above, and everything is passing. gdb/ChangeLog: 2015-04-08 Sergio Durigan Junior <sergiodj@redhat.com> PR python/16699 * python/py-cmd.c (cmdpy_completer_helper): Adjust function to not use a caching mechanism. Adjust comments and code to reflect that. Replace 'sizeof' by 'strlen' when fetching 'wordobj'. (cmdpy_completer_handle_brkchars): Adjust call to cmdpy_completer_helper. Call Py_XDECREF for 'resultobj'. (cmdpy_completer): Likewise. gdb/testsuite/ChangeLog: 2015-04-08 Keith Seitz <keiths@redhat.com> PR python/16699 * gdb.python/py-completion.exp: New tests for completion. * gdb.python/py-completion.py (CompleteLimit1): New class. (CompleteLimit2): Likewise. (CompleteLimit3): Likewise. (CompleteLimit4): Likewise. (CompleteLimit5): Likewise. (CompleteLimit6): Likewise. (CompleteLimit7): Likewise.
2015-01-01Update year range in copyright notice of all files owned by the GDB project.Joel Brobecker1-1/+1
gdb/ChangeLog: Update year range in copyright notice of all files.
2014-09-03PR python/16699: GDB Python command completion with overriden complete vs. ↵Sergio Durigan Junior1-0/+58
completer class This PR came from a Red Hat bug that was filed recently. I checked and it still exists on HEAD, so here's a proposed fix. Although this is marked as a Python backend bug, this is really about the completion mechanism used by GDB. Since this code reminds me of my first attempt to make a good noodle, it took me quite some time to fix it in a non-intrusive way. The problem is triggered when one registers a completion method inside a class in a Python script, rather than registering the command using a completer class directly. For example, consider the following script: class MyFirstCommand(gdb.Command): def __init__(self): gdb.Command.__init__(self,'myfirstcommand',gdb.COMMAND_USER,gdb.COMPLETE_FILENAME) def invoke(self,argument,from_tty): raise gdb.GdbError('not implemented') class MySecondCommand(gdb.Command): def __init__(self): gdb.Command.__init__(self,'mysecondcommand',gdb.COMMAND_USER) def invoke(self,argument,from_tty): raise gdb.GdbError('not implemented') def complete(self,text,word): return gdb.COMPLETE_FILENAME MyFirstCommand () MySecondCommand () When one loads this into GDB and tries to complete filenames for both myfirstcommand and mysecondcommand, she gets: (gdb) myfirstcommand /hom<TAB> (gdb) myfirstcommand /home/ ^ ... (gdb) mysecondcommand /hom<TAB> (gdb) mysecondcommand /home ^ (The "^" marks the final position of the cursor after the TAB). So we see that myfirstcommand honors the COMPLETE_FILENAME class (as specified in the command creation), but mysecondcommand does not. After some investigation, I found that the problem lies with the set of word break characters that is used for each case. The set should be the same for both commands, but it is not. During the process of deciding which type of completion should be used, the code in gdb/completer.c:complete_line_internal analyses the command that requested the completion and tries to determine the type of completion wanted by checking which completion function will be called (e.g., filename_completer for filenames, location_completer for locations, etc.). This all works fine for myfirstcommand, because immediately after the command registration the Python backend already sets its completion function to filename_completer (which then causes the complete_line_internal function to choose the right set of word break chars). However, for mysecondcommand, this decision is postponed to when the completer function is evaluated, and the Python backend uses an internal completer (called cmdpy_completer). complete_line_internal doesn't know about this internal completer, and can't choose the right set of word break chars in time, which then leads to a bad decision when completing the "/hom" word. So, after a few attempts, I decided to create another callback in "struct cmd_list_element" that will be responsible for handling the case when there is an unknown completer function for complete_line_internal to work with. So far, only the Python backend uses this callback, and only when the user provides a completer method instead of registering the command directly with a completer class. I think this is the best option because it not very intrusive (all the other commands will still work normally), but especially because the whole completion code is so messy that it would be hard to fix this without having to redesign things. I have regtested this on Fedora 18 x86_64, without regressions. I also included a testcase. gdb/ChangeLog: 2014-09-03 Sergio Durigan Junior <sergiodj@redhat.com> PR python/16699 * cli/cli-decode.c (set_cmd_completer_handle_brkchars): New function. (add_cmd): Set "completer_handle_brkchars" to NULL. * cli/cli-decode.h (struct cmd_list_element) <completer_handle_brkchars>: New field. * command.h (completer_ftype_void): New typedef. (set_cmd_completer_handle_brkchars): New prototype. * completer.c (set_gdb_completion_word_break_characters): New function. (complete_line_internal): Call "completer_handle_brkchars" callback from command. * completer.h: Include "command.h". (set_gdb_completion_word_break_characters): New prototype. * python/py-cmd.c (cmdpy_completer_helper): New function. (cmdpy_completer_handle_brkchars): New function. (cmdpy_completer): Adjust to use cmdpy_completer_helper. (cmdpy_init): Set completer_handle_brkchars to cmdpy_completer_handle_brkchars. gdb/testsuite/ChangeLog: 2014-09-03 Sergio Durigan Junior <sergiodj@redhat.com> PR python/16699 * gdb.python/py-completion.exp: New file. * gdb.python/py-completion.py: Likewise.