I recently wanted to enable some gdb logging when running the internal
AdaCore test suite. To do this nicely, I enable debug-redirect early
in the test, so that the logging output does not affect the test
results.
I also wanted to the log the commands, to correlate what I see in the
debug log with what I see in the ordinary test suite log file (which
is basically like our own gdb.log).
However, I found that "set trace-commands on" will log to stdout, not
stdlog. This patch changes this to log to the log file instead.
This changes some throw_error calls to apply file_name_style and
line_number_style. This patch does both at the same time because the
two styles often appear in the same message.
This changes a number of error messages in gdb to use command_style.
In some places I've added double quotes around the command name for
consistency with other messages.
Approved-By: Andrew Burgess <aburgess@redhat.com>
Replace all occurrences of:
strcmp (...) == 0
strcmp (...) != 0
!strcmp (...)
0 == strcmp (...)
strcmp (...) directly used as a boolean predicate
with the equivalent expression using streq.
This is for consistency (we already use streq as some places in the
testsuite) but also for clarity. I think that streq is clearer on the
intent than strcmp. It's also a bit shorter.
Change-Id: Ibbf5261b1872c240bc0c982c147f6a5477275a91
Approved-By: Andrew Burgess <aburgess@redhat.com>
This updates the copyright headers to include 2026. I did this by
running gdb/copyright.py and then manually modifying a few files as
noted by the script.
I looked through gdb for instance of:
while (*p == ' ' || *p == '\t')
p++;
... and replaced these with a call to skip_spaces.
In some cases this might slightly change the semantics, as now other
whitespace (like \r or \f) will be considered. However I don't think
this matters.
Regression tested on x86-64 Fedora 41.
Approved-By: Simon Marchi <simon.marchi@efficios.com>
Replace some explicitly deleted copy constructor and copy assignment
operator with the DISABLE_COPY_AND_ASSIGN macro for consistency
with the rest of the codebase.
Change-Id: If3fe2c4d7b3cb4530eace86d589116f805c7656f
Approved-By: Tom Tromey <tom@tromey.com>
I noticed my IDE (VSCode) starting to automatically trim trailing
whitespaces on save, despite the setting for it being disabled. I
realized that this is because the .editorconfig file now has
trim_trailing_whitespace = true
for many file types. If we have this EditorConfig setting forcing
editors to trim trailing whitespaces, I think it would make sense to
clean up trailing whitespaces from our files. Otherwise, people will
always get spurious whitespace changes when editing these files.
I did a mass cleanup using this command:
$ find gdb gdbserver gdbsupport -type f \( \
-name "*.c" -o \
-name "*.h" -o \
-name "*.cc" -o \
-name "*.texi" -o \
-name "*.exp" -o \
-name "*.tcl" -o \
-name "*.py" -o \
-name "*.s" -o \
-name "*.S" -o \
-name "*.asm" -o \
-name "*.awk" -o \
-name "*.ac" -o \
-name "Makefile*" -o \
-name "*.sh" -o \
-name "*.adb" -o \
-name "*.ads" -o \
-name "*.d" -o \
-name "*.go" -o \
-name "*.F90" -o \
-name "*.f90" \
\) -exec sed -ri 's/[ \t]+$//' {} +
I then did an autotools regen, because we don't actually want to change
the Makefile and Makefile.in files that are generated.
Change-Id: I6f91b83e3b8c4dc7d5d51a2ebf60706120efe691
PR ada/33217 points out that gdb incorrectly calls the <ctype.h>
functions. In particular, gdb feels free to pass a 'char' like:
char *str = ...;
... isdigit (*str)
This is incorrect as isdigit only accepts EOF and values that can be
represented as 'unsigned char' -- that is, a cast is needed here to
avoid undefined behavior when 'char' is signed and a character in the
string might be sign-extended. (As an aside, I think this API seems
obviously bad, but unfortunately this is what the standard says, and
some systems check this.)
Rather than adding casts everywhere, this changes all the code in gdb
that uses any <ctype.h> API to instead call the corresponding c-ctype
function.
Now, c-ctype has some limitations compared to <ctype.h>. It works as
if the C locale is in effect, so in theory some non-ASCII characters
may be misclassified. This would only affect a subset of character
sets, though, and in most places I think ASCII is sufficient -- for
example the many places in gdb that check for whitespace.
Furthermore, in practice most users are using UTF-8-based locales,
where these functions aren't really informative for non-ASCII
characters anyway; see the existing workarounds in gdb/c-support.h.
Note that safe-ctype.h cannot be used because it causes conflicts with
readline.h. And, we canot poison the <ctype.h> identifiers as this
provokes errors from some libstdc++ headers.
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=33217
Approved-By: Simon Marchi <simon.marchi@efficios.com>
This patch introduces a new macro, INIT_GDB_FILE. This is used to
replace the current "_initialize_" idiom when introducing a per-file
initialization function. That is, rather than write:
void _initialize_something ();
void
_initialize_something ()
{
...
}
... now you would write:
INIT_GDB_FILE (something)
{
...
}
The macro handles both the declaration and definition of the function.
The point of this approach is that it makes it harder to accidentally
cause an initializer to be omitted; see commit 2711e475 ("Ensure
cooked_index_entry self-tests are run"). Specifically, the regexp now
used by make-init-c seems harder to trick.
New in v2: un-did some erroneous changes made by the script.
The bulk of this patch was written by script.
Regression tested on x86-64 Fedora 41.
This updates the copyright headers to include 2025. I did this by
running gdb/copyright.py and then manually modifying a few files as
noted by the script.
Approved-By: Eli Zaretskii <eliz@gnu.org>
Consider this backtrace within GDB:
#0 notify_breakpoint_modified (b=0x57d31d0) at ../../src/gdb/breakpoint.c:1083
#1 0x00000000005b6406 in breakpoint_set_commands (b=0x57d31d0, commands=...) at ../../src/gdb/breakpoint.c:1523
#2 0x00000000005c8c63 in update_dprintf_command_list (b=0x57d31d0) at ../../src/gdb/breakpoint.c:8641
#3 0x00000000005d3c4e in dprintf_breakpoint::re_set (this=0x57d31d0) at ../../src/gdb/breakpoint.c:12476
#4 0x00000000005d6347 in breakpoint_re_set () at ../../src/gdb/breakpoint.c:13298
Whenever breakpoint_re_set is called we re-build the commands that the
dprintf b/p will execute and store these into the breakpoint. The
commands are re-built in update_dprintf_command_list and stored into
the breakpoint object in breakpoint_set_commands.
Now sometimes these commands can change, dprintf_breakpoint::re_set
explains one case where this can occur, and I'm sure there must be
others. But in most cases the commands we recalculate will not
change. This means that the breakpoint modified event which is
emitted from breakpoint_set_commands is redundant.
This commit aims to eliminate the redundant breakpoint modified events
for dprintf breakpoints. This is done by adding a commands_equal call
to the start of breakpoint_set_commands.
The commands_equal function is a new function which compares two
command_line objects and returns true if they are identical. Using
this function we can check if the new commands passed to
breakpoint_set_commands are identical to the breakpoint's existing
commands. If the new commands are equal then we don't need to change
anything on the new breakpoint, and the breakpoint modified event can
be skipped.
The test for this commit stops at a dlopen() call in the inferior,
sets up a dprintf breakpoint, then uses 'next' to step over the
dlopen() call. When the library loads GDB call breakpoint_re_set,
which calls dprintf_breakpoint::re_set. But in this case we don't
expect the calculated command string to change, so we don't expect to
see the breakpoint modified event.
GDB's compile subsystem is deeply tied to GDB's ability to understand
DWARF. A future patch will add the option to disable DWARF at configure
time, but for that to work, the compile subsystem will need to be
entirely disabled as well, so this patch adds that possibility.
I also think there is motive for a security conscious user to disable
compile for it's own sake. Considering that the code is quite
unmaintained, and depends on an equally unmaintained gcc plugin, there
is a case to be made that this is an unnecessary increase in the attack
surface if a user knows they won't use the subsystem. Additionally, this
can make compilation slightly faster and the final binary is around 3Mb
smaller. But these are all secondary to the main goal of being able to
disable dwarf at configure time.
To be able to achieve optional compilation, some of the code that
interfaces with compile had to be changed. All parts that directly
called compile things have been wrapped by ifdefs checking for compile
support. The file compile/compile.c has been setup in a similar way to
how python's and guile's main file has been setup, still being compiled
but only for with placeholder command.
Finally, to avoid several new errors, a new TCL proc was introduced to
gdb.exp, allow_compile_tests, which checks if the "compile" command is
recognized before the inferior is started and otherwise skips the compile
tests. All tests in the gdb.compile subfolder have been updated to use
that, and the test gdb.base/filename-completion also uses this. The proc
skip_compile_feature_tests to recognize when the subsystem has been
disabled at compile time.
Reviewed-By: Eli Zaretskii <eliz@gnu.org>
Approved-By: Tom Tromey <tom@tromey.com>
Currently, gdb.execute emits styled output when the command is sending
its output to GDB's stdout, and produces unstyled output when the
output is going to a string.
But it is not unreasonable that a user might wish to capture styled
output from a gdb.execute call, for example, the user might want to
display the styled output are part of some larger UI output block.
At the same time, I don't think it makes sense to always produce
styled output when capturing the output in a string; if what the user
wants is to parse the output, then the style escape sequences make
this far harder.
I propose that gdb.execute gain a new argument 'styling'. When False
we would always produce unstyled output, and when True we would
produce styled output if styling is not disabled by some other means.
For example, if GDB's 'set style enabled' is off, then I think
gdb.execute() should respect that. My assumption here is that
gdb.execute() might be executed by some extension. If the extension
thinks "styled output world work here", but the user hates styled
output, and has turned it off, then the extension should not be
forcing styled output on the user.
I chose 'styling' instead of 'styled' as the Python argument name
because we already use 'styling' in gdb.Value.format_string, and we
don't use 'styled' anywhere else. This is only a little bit of
consistency, but I still think it's a good thing.
The default for 'styling' will change depending on where the output is
going. When gdb.execute is sending the output to GDB's stdout then
the default for 'styling' is True. When the output is going to a
string, then the default for 'styling' will be False. Not only does
this match the existing behaviour, but I think this makes sense. By
default we assume that output captured in a string is going to be
parsed, and therefore styling markup is unhelpful, while output going
to stdout should receive styling.
This fixes part of the problem described in PR gdb/32676. That bug
tries to capture styled source listing in a string, which wasn't
previously possible.
There are some additional issues with capturing source code; GDB
caches the source code in the source code cache. However, GDB doesn't
check if the cached content is styled or not. As a consequence, if
the first time the source of a file is shown it is unstyled, then the
cached will hold the unstyled source code, and future requests will
return that unstyled source. I'll address this issue in a separate
patch.
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=32676
Approved-By: Tom Tromey <tom@tromey.com>
Currently the "title" style is only used when printing command names.
The "title" name itself is probably a misnomer, but meanwhile this
patch changes the existing uses to instead use the new "command" style
for consistency.
The "title" style is not removed; see the next patch.
Reviewed-By: Keith Seitz <keiths@redhat.com>
Approved-By: Andrew Burgess <aburgess@redhat.com>
Most files including gdbcmd.h currently rely on it to access things
actually declared in cli/cli-cmds.h (setlist, showlist, etc). To make
things easy, replace all includes of gdbcmd.h with includes of
cli/cli-cmds.h. This might lead to some unused includes of
cli/cli-cmds.h, but it's harmless, and much faster than going through
the 170 or so files by hand.
Change-Id: I11f884d4d616c12c05f395c98bbc2892950fb00f
Approved-By: Tom Tromey <tom@tromey.com>
Move some declarations related to the "quit" machinery from defs.h to
event-top.h. Most of the definitions associated to these declarations
are in event-top.c. The exceptions are `quit()` and `maybe_quit()`,
that are defined in utils.c. For consistency, move these two
definitions to event-top.c.
Include "event-top.h" in many files that use these things.
Change-Id: I6594f6df9047a9a480e7b9934275d186afb14378
Approved-By: Tom Tromey <tom@tromey.com>
Now that defs.h, server.h and common-defs.h are included via the
`-include` option, it is no longer necessary for source files to include
them. Remove all the inclusions of these files I could find. Update
the generation scripts where relevant.
Change-Id: Ia026cff269c1b7ae7386dd3619bc9bb6a5332837
Approved-By: Pedro Alves <pedro@palves.net>
Currently gdb.parameter doesn't raise an exception if an
ambiguous name is used, it instead returns the value of the
last partly matching parameter:
```
(gdb) show print sym
Ambiguous show print command "sym": symbol, symbol-filename, symbol-loading.
(gdb) show print symbol-loading
Printing of symbol loading messages is "full".
(gdb) py print(gdb.parameter("print sym"))
full
```
It's because lookup_cmd_composition_1 tries to detect
ambigous names by checking the return value of find_cmd
for CMD_LIST_AMBIGUOUS, which never happens, since only
lookup_cmd_1 returns CMD_LIST_AMBIGUOUS.
Instead the nfound argument contains the number of found
matches.
By using it instead, and by setting *CMD to the special value
CMD_LIST_AMBIGUOUS in this case, gdbpy_parameter can now show
the appropriate error message:
```
(gdb) py print(gdb.parameter("print sym"))
Traceback (most recent call last):
File "<string>", line 1, in <module>
RuntimeError: Parameter `print sym' is ambiguous.
Error while executing Python code.
(gdb) py print(gdb.parameter("print symbol"))
True
(gdb) py print(gdb.parameter("print symbol-"))
Traceback (most recent call last):
File "<string>", line 1, in <module>
RuntimeError: Parameter `print symbol-' is ambiguous.
Error while executing Python code.
(gdb) py print(gdb.parameter("print symbol-load"))
full
```
Since the document command also uses lookup_cmd_composition, it needed
to check for CMD_LIST_AMBIGUOUS as well, so it now also shows an
"Ambiguous command" error message in this case.
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=14639
Approved-By: Tom Tromey <tom@tromey.com>
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.
Given that GDB now requires a C++17, replace all uses of
gdb::string_view with std::string_view.
This change has mostly been done automatically:
- gdb::string_view -> std::string_view
- #include "gdbsupport/gdb_string_view.h" -> #include <string_view>
One things which got brought up during review is that gdb::stging_view
does support being built from "nullptr" while std::sting_view does not.
Two places are manually adjusted to account for this difference:
gdb/tui/tui-io.c:tui_getc_1 and
gdbsupport/format.h:format_piece::format_piece.
The above automatic change transformed
"gdb::to_string (const gdb::string_view &)" into
"gdb::to_string (const std::string_view &)". The various direct users
of this function are now explicitly including
"gdbsupport/gdb_string_view.h". A later patch will remove the users of
gdb::to_string.
The implementation and tests of gdb::string_view are unchanged, they will
be removed in a following patch.
Change-Id: Ibb806a7e9c79eb16a55c87c6e41ad396fecf0207
Approved-By: Tom Tromey <tom@tromey.com>
Approved-By: Pedro Alves <pedro@palves.net>
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
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.
[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>
PR cli/29800 points out that "document" will now crash when the
argument is an undefined command. This is a regression due to the
"document user-defined aliases" patch.
Approved-By: Joel Brobecker <brobecker@adacore.com>
Reviewed-By: Philippe Waroquiers <philippe.waroquiers@skynet.be>
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=29800
Currently, every internal_error call must be passed __FILE__/__LINE__
explicitly, like:
internal_error (__FILE__, __LINE__, "foo %d", var);
The need to pass in explicit __FILE__/__LINE__ is there probably
because the function predates widespread and portable variadic macros
availability. We can use variadic macros nowadays, and in fact, we
already use them in several places, including the related
gdb_assert_not_reached.
So this patch renames the internal_error function to something else,
and then reimplements internal_error as a variadic macro that expands
__FILE__/__LINE__ itself.
The result is that we now should call internal_error like so:
internal_error ("foo %d", var);
Likewise for internal_warning.
The patch adjusts all calls sites. 99% of the adjustments were done
with a perl/sed script.
The non-mechanical changes are in gdbsupport/errors.h,
gdbsupport/gdb_assert.h, and gdb/gdbarch.py.
Approved-By: Simon Marchi <simon.marchi@efficios.com>
Change-Id: Ia6f372c11550ca876829e8fd85048f4502bdcf06
I looked at all the spots using value_mark, and converted all the
straightforward ones to use scoped_value_mark instead.
Regression tested on x86-64 Fedora 34.
Compared to the previous version, this version fixes the comments reported by
Tom Tromey and ensures that the 'help some-user-documented-alias'
shows the alias definition to ensure the user understands this is an
alias even if specifically documented.
When using 'help ALIASNAME', GDB shows the help of the aliased command.
This is a good default behaviour.
However, GDB alias command allows to define aliases with arguments
possibly changing or tuning significantly the behaviour of
the aliased command. In such a case, showing the help of the aliased
command might not be ideal.
This is particularly true when defining an alias as a set of
nested 'with' followed by a last command to launch, such as:
(gdb) alias pp10 = with print pretty -- with print elements 10 -- print
Asking 'help pp10' shows the help of the 'with' command, which is
not particularly useful:
(gdb) help pp10
with, pp10, w
alias pp10 = with print pretty -- with print elements 10 -- print
Temporarily set SETTING to VALUE, run COMMAND, and restore SETTING.
Usage: with SETTING [VALUE] [-- COMMAND]
....
Such an alias can now be documented by the user:
(gdb) document pp10
>Pretty printing an expressiong, printing 10 elements.
>Usage: pp10 [PRINT-COMMAND-OPTIONS] EXP
>See 'help print' for more information.
>end
(gdb) help pp10
alias pp10 = with print pretty -- with print elements 10 -- print
Pretty printing an expressiong, printing 10 elements.
Usage: pp10 [PRINT-COMMAND-OPTIONS] EXP
See 'help print' for more information.
(gdb)
When a user-defined alias is documented specifically, help and apropos
use the provided alias documentation instead of the documentation of
the aliased command.
Such a documented alias is also not shown anymore in the help of the
aliased command, and the alias is not listed anymore in the help
of the aliased command. In particular for cases such as pp10 example above,
indicating that pp10 is an alias of the 'with' command is confusing.
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.
Now that filtered and unfiltered output can be treated identically, we
can unify the puts family of functions. This is done under the name
"gdb_puts". Most of this patch was written by script.
Now that filtered and unfiltered output can be treated identically, we
can unify the vprintf family of functions: vprintf_filtered,
vprintf_unfiltered, vfprintf_filtered and vfprintf_unfiltered. (For
the gdb_stdout variants, recall that only printf_unfiltered gets truly
unfiltered output at this point.) This removes one such function and
renames the remaining two to "gdb_vprintf". All callers are updated.
Much of this patch was written by script.
execute_control_commands_to_string can be rewritten in terms of
execute_fn_to_string, which consolidates some knowledge about which
streams to redirect.
Regression tested on x86-64 Fedora 34.
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.
I noticed that value_true is declared in language.h and defined in
language.c. However, as part of the value API, I think it would be
better in one of those files. And, because it is very short, I
changed it to be an inline function in value.h. I've also removed a
comment from the implementation, on the basis that it seems obsolete
-- if the change it suggests was needed, it probably would have been
done by now; and if it is needed in the future, odds are it would be
done differently anyway.
Finally, this patch also changes value_true and value_logical_not to
return a bool, and updates some uses.
In cli/cli-script.c, process_next_line() allocates memory
which will eventually end up being assigned to the 'next'
field in struct command_line. However, in a case
recurse_read_control_structure returns 'invalid_control'
this memory is leaked. This commit uses std::unique_ptr
as appropriate to prevent this leakage.
This issue was found by coverity scanning.
gdb/ChangeLog:
* cli/cli-script.h (command_line_up): New unique_ptr typedef.
* cli/cli-script.c (multi_line_command_p): Use unique_ptr
command_line_up instead of struct command_line.
(build_command_line): Likewise.
(get_command_line): Update the cmd function call parameter.
(process_next_line): Use unique_ptr command_line_up instead
of struct command_line.
(recurse_read_control_structure): Change the the type of
next to command_line_up.
(read_command_lines_1): Change type of `next' to be
command_line_up and update all references of `next'
accordingly.
Same idea as the previous patch, but for prefix instead of alias.
gdb/ChangeLog:
* cli/cli-decode.h (cmd_list_element) <is_prefix>: New, use it.
Change-Id: I76a9d2e82fc8d7429904424674d99ce6f9880e2b
While browsing this code, I found the name "prefixlist" really
confusing. I kept reading it as "list of prefixes". Which it isn't:
it's a list of sub-commands, for a prefix command. I think that
renaming it to "subcommands" would make things clearer.
gdb/ChangeLog:
* Rename "prefixlist" parameters to "subcommands" throughout.
* cli/cli-decode.h (cmd_list_element) <prefixlist>: Rename to...
<subcommands>: ... this.
* cli/cli-decode.c (lookup_cmd_for_prefixlist): Rename to...
(lookup_cmd_with_subcommands): ... this.
Change-Id: I150da10d03052c2420aa5b0dee41f422e2a97928
Previously, the prefixname field of struct cmd_list_element was manually
set for prefix commands. This seems verbose and error prone as it
required every single call to functions adding prefix commands to
specify the prefix name while the same information can be easily
generated.
Historically, this was not possible as the prefix field was null for
many commands, but this was fixed in commit
3f4d92ebdf by Philippe Waroquiers, so
we can rely on the prefix field being set when generating the prefix
name.
This commit also fixes a use after free in this scenario:
* A command gets created via Python (using the gdb.Command class).
The prefix name member is dynamically allocated.
* An alias to the new command is created. The alias's prefixname is set
to point to the prefixname for the original command with a direct
assignment.
* A new command with the same name as the Python command is created.
* The object for the original Python command gets freed and its
prefixname gets freed as well.
* The alias is updated to point to the new command, but its prefixname
is not updated so it keeps pointing to the freed one.
gdb/ChangeLog:
* command.h (add_prefix_cmd): Remove the prefixname argument as
it can now be generated automatically. Update all callers.
(add_basic_prefix_cmd): Ditto.
(add_show_prefix_cmd): Ditto.
(add_prefix_cmd_suppress_notification): Ditto.
(add_abbrev_prefix_cmd): Ditto.
* cli/cli-decode.c (add_prefix_cmd): Ditto.
(add_basic_prefix_cmd): Ditto.
(add_show_prefix_cmd): Ditto.
(add_prefix_cmd_suppress_notification): Ditto.
(add_prefix_cmd_suppress_notification): Ditto.
(add_abbrev_prefix_cmd): Ditto.
* cli/cli-decode.h (struct cmd_list_element): Replace the
prefixname member variable with a method which generates the
prefix name at runtime. Update all code reading the prefix
name to use the method, and remove all code setting it.
* python/py-cmd.c (cmdpy_destroyer): Remove code to free the
prefixname member as it's now a method.
(cmdpy_function): Determine if the command is a prefix by
looking at prefixlist, not prefixname.
In code dealing with commands, there's a pattern repeated a few times of
calling lookup_cmd with some speficic arguments and then using strcmp
on the returned command to check for an exact match.
As a later patch would add a few more similar lines of code, this patch
adds a new lookup_cmd_exact function which simplify this use case.
gdb/ChangeLog:
* cli/cli-decode.c (lookup_cmd_exact): Add.
* cli/cli-script.c (do_define_command): Use lookup_cmd_exact.
(define_prefix_command): Ditto.
* command.h: Add lookup_cmd_exact.
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.
"document" command executed in python, gdb.execute("document
<comname>\n...\nend\n"), will wait for user input. Python extension stops
working from that point.
multi-line suport was introduced in commit 56bcdbea2. But "document" support
seem to be implemented.
gdb/ChangeLog:
2020-12-02 Rae Kim <rae.kim@gmail.com>
* cli/cli-script.c (do_document_command): Rename from
document_command. Handle multi-line input.
(multi_line_command_p): Handle document_control.
(build_command_line): Likewise.
(execute_control_command_1): Likewise.
(process_next_line): Likewise.
(document_command): Call do_document_command.
* cli/cli-script.h (enum command_control_type): Add
document_control.
gdb/testsuite/ChangeLog:
2020-12-02 Rae Kim <rae.kim@gmail.com>
* gdb.base/document.exp: New test.
Change-Id: Ice262b980c05051de4c106af9f3fde5b2a6df6fe
Prior to commit 56bcdbea2b, the from_tty keyword argument to the
Python function gdb.execute controlled whether the command took input
from the terminal. When from_tty=True, "starti" and similar commands
prompted the user:
(gdb) python gdb.execute("starti", from_tty=True)
The program being debugged has been started already.
Start it from the beginning? (y or n) y
Starting program: /bin/true
Program stopped.
When from_tty=False, these commands did not prompt the user, and "yes"
was assumed:
(gdb) python gdb.execute("starti", from_tty=False)
Program stopped.
However, after commit 56bcdbea2b, the from_tty keyword argument no
longer had this effect. For example, as of commit 7ade7fba75:
(gdb) python gdb.execute("starti", from_tty=True)
The program being debugged has been started already.
Start it from the beginning? (y or n) [answered Y; input not from terminal]
Starting program: /bin/true
Program stopped.
Note the "[answered Y; input not from terminal]" in the output even
though from_tty=True was requested.
Looking at commit 56bcdbea2b, it seems that the behaviour of the
from_tty argument was changed accidentally. The commit message said:
Let gdb.execute handle multi-line commands
This changes the Python API so that gdb.execute can now handle
multi-line commands, like "commands" or "define".
and there was no mention of changing the effect of the from_tty
argument. It looks as though the code for setting the instream to
nullptr was accidentally moved from execute_user_command() to
execute_control_commands() along with the other scoped restores.
Accordingly, the simplest way to fix this is to partially reverse
commit 56bcdbea2b by moving the code for setting the instream to
nullptr back to execute_user_command() where it was to begin with.
Additionally, add a test case to reduce the risk of similar breakage
in future.
gdb/ChangeLog:
PR python/26586
* cli/cli-script.c (execute_control_commands): don't set
instream to nullptr here as this breaks the from_tty argument
to gdb.execute in Python.
(execute_user_command): set instream to nullptr here instead.
gdb/testsuite/ChangeLog:
PR python/26586
* gdb.python/python.exp: add test cases for the from_tty
argument to gdb.execute.
Currently, a user can define an alias, but cannot have default
arguments for this alias.
This patch modifies the 'alias' command so that default args can
be provided.
(gdb) h alias
Define a new command that is an alias of an existing command.
Usage: alias [-a] [--] ALIAS = COMMAND [DEFAULT-ARGS...]
ALIAS is the name of the alias command to create.
COMMAND is the command being aliased to.
Options:
-a
Specify that ALIAS is an abbreviation of COMMAND.
Abbreviations are not used in command completion..
GDB will automatically prepend the provided DEFAULT-ARGS to the list
of arguments explicitly provided when using ALIAS.
Use "help aliases" to list all user defined aliases and their default args.
Examples:
Make "spe" an alias of "set print elements":
alias spe set print elements
Make "elms" an alias of "elements" in the "set print" command:
alias -a set print elms set print elements
Make "btf" an alias of "backtrace -full -past-entry -past-main" :
alias btf = backtrace -full -past-entry -past-main
Make "wLapPeu" an alias of 2 nested "with":
alias wLapPeu = with language pascal -- with print elements unlimited --
(gdb)
The way 'default-args' is implemented makes it trivial to set default
args also for GDB commands (such as "backtrace") and for GDB pre-defined
aliases (such as "bt"). It was however deemed better to not allow to
define default arguments for pre-defined commands and aliases, to avoid
users believing that e.g. default args for "backtrace" would apply to "bt".
If needed, default-args could be allowed for GDB predefined commands
and aliases by adding a command
'set default-args GDB_COMMAND_OR_PREDEFINED_ALIAS [DEFAULT-ARGS...]'.
* 'alias' command now has a completer that helps to complete:
- ALIAS (if the user defines an alias after a prefix),
- the aliased COMMAND
- the possible options for the aliased COMMAND.
* Help and apropos commands show the definitions of the aliases
that have default arguments, e.g.
(gdb) help backtrace
backtrace, btf, where, bt
alias btf = backtrace -full -past-entry -past-main
Print backtrace of all stack frames, or innermost COUNT frames.
Usage: backtrace [OPTION]... [QUALIFIER]... [COUNT | -COUNT]
Options:
-entry-values no|only|preferred|if-needed|both|compact|default
Set printing of function arguments at function entry.
...
gdb/ChangeLog
2020-06-22 Philippe Waroquiers <philippe.waroquiers@skynet.be>
* cli/cli-cmds.c (lookup_cmd_for_default_args)
(alias_command_completer)
(make_alias_options_def_group): New functions.
(alias_opts, alias_option_defs): New struct and array.
(alias_usage_error): Update usage.
(alias_command): Handles optional DEFAULT-ARGS... arguments.
Use option framework.
(_initialize_cli_cmds): Update alias command help.
Update aliases command help.
(show_user):
Add NULL for new default_args lookup_cmd argument.
(valid_command_p): Rename to validate_aliased_command.
Add NULL for new default_args lookup_cmd argument. Verify that the
aliased_command has no default args.
* cli/cli-decode.c (help_cmd): Show aliases definitions.
(lookup_cmd_1, lookup_cmd): New argument default_args.
(add_alias_cmd):
Add NULL for new default_args lookup_cmd argument.
(print_help_for_command): Show default args under the layout
alias some_alias = some_aliased_cmd some_alias_default_arg.
* cli/cli-decode.h (struct cmd_list_element): New member default_args.
xfree default_args in destructor.
* cli/cli-script.c (process_next_line, do_define_command):
Add NULL for new default_args lookup_cmd argument.
* command.h: Declare new default_args argument in lookup_cmd
and lookup_cmd_1.
* completer.c (complete_line_internal_1):
Add NULL for new default_args lookup_cmd or lookup_cmd_1 argument.
* guile/scm-cmd.c (gdbscm_parse_command_name): Likewise.
* guile/scm-param.c (add_setshow_generic, pascm_parameter_defined_p):
Likewise.
* infcmd.c (_initialize_infcmd): Likewise.
* python/py-auto-load.c (gdbpy_initialize_auto_load): Likewise.
* python/py-cmd.c (gdbpy_parse_command_name): Likewise.
* python/py-param.c (add_setshow_generic): Likewise.
* remote.c (_initialize_remote): Likewise.
* top.c (execute_command): Prepend default_args if command has some.
(set_verbose):
Add NULL for new default_args lookup_cmd or lookup_cmd_1 argument.
* tracepoint.c (validate_actionline, encode_actions_1):
Add NULL for new default_args lookup_cmd or lookup_cmd_1 argument.
I was inspired by a series of patches merged by Alan Modra in the other
projects, so I did the same in GDB with a bit of Coccinelle and grep.
This patch removes the unnecessary NULL checks before calls to xfree.
They are unnecessary because xfree already does a NULL check. Since
free is supposed to handle NULL values correctly, the NULL check in
xfree itself is also questionable, but I've left it there for now.
gdb/ChangeLog:
* coffread.c (patch_type): Remove NULL check before xfree.
* corefile.c (set_gnutarget): Likewise.
* cp-abi.c (set_cp_abi_as_auto_default): Likewise.
* exec.c (build_section_table): Likewise.
* remote.c (remote_target::pass_signals): Likewise.
* utils.c (n_spaces): Likewise.
* cli/cli-script.c (document_command): Likewise.
* i386-windows-tdep.c (core_process_module_section): Likewise.
* linux-fork.c (struct fork_info) <~fork_info>: Likewise.
