[RFAv5,3/3] NEWS and documentation for default-args related concept and commands.

Message ID 20200307131428.11942-4-philippe.waroquiers@skynet.be
State New
Headers show
Series
  • Allow the user to define default args for commands and aliases
Related show

Commit Message

Philippe Waroquiers March 7, 2020, 1:14 p.m.
gdb/ChangeLog
YYYY-MM-DD  Philippe Waroquiers  <philippe.waroquiers@skynet.be>

	* NEWS: Mention new default-args commands.  Mention change
	to the alias command.

gdb/doc/ChangeLog
YYYY-MM-DD  Philippe Waroquiers  <philippe.waroquiers@skynet.be>

	* gdb.texinfo (Command default args): New node documenting
	'set|show default-args' and 'set|show enable-default-args'.
	(Aliases): Document the new 'DEFAULT-ARGS...' option.
---
 gdb/NEWS            |  29 +++++++++
 gdb/doc/gdb.texinfo | 139 +++++++++++++++++++++++++++++++++++++++++++-
 2 files changed, 167 insertions(+), 1 deletion(-)

-- 
2.20.1

Comments

Eli Zaretskii March 7, 2020, 2:37 p.m. | #1
> From: Philippe Waroquiers <philippe.waroquiers@skynet.be>

> Date: Sat,  7 Mar 2020 14:14:28 +0100

> 

> gdb/ChangeLog

> YYYY-MM-DD  Philippe Waroquiers  <philippe.waroquiers@skynet.be>

> 

> 	* NEWS: Mention new default-args commands.  Mention change

> 	to the alias command.

> 

> gdb/doc/ChangeLog

> YYYY-MM-DD  Philippe Waroquiers  <philippe.waroquiers@skynet.be>

> 

> 	* gdb.texinfo (Command default args): New node documenting

> 	'set|show default-args' and 'set|show enable-default-args'.

> 	(Aliases): Document the new 'DEFAULT-ARGS...' option.


This is OK, but ...

> +For more information about @var{default-args}, see @ref{Command default args,

> +,Automatically prepend default arguments to commands and aliases}


That cross-reference needs a period after the right brace.

Thanks.

Patch

diff --git a/gdb/NEWS b/gdb/NEWS
index 6657f6fadc..62dea7e983 100644
--- a/gdb/NEWS
+++ b/gdb/NEWS
@@ -55,10 +55,39 @@  show exec-file-mismatch -- Show exec-file-mismatch handling (ask|warn|off).
   whether to load the process executable file; if 'warn', just display
   a warning; if 'off', don't attempt to detect a mismatch.
 
+set default-args COMMAND [DEFAULT-ARGS...]
+show default-args [COMMAND]
+set enable-default-args [on|off]
+show enable-default-args
+  GDB can now automatically prepend default arguments to the argument list
+  provided explicitely by the user.
+  This allows to set default arguments or options for the GDB commands
+  or define easily more specialised aliases.
+  For example, 'set default-args backtrace -full -frame-arguments all'
+  ensures that backtrace will automatically use the options -full
+  -frame-arguments all, without having to retype them for each backtrace
+  command.
+
 tui new-layout NAME WINDOW WEIGHT [WINDOW WEIGHT]...
   Define a new TUI layout, specifying its name and the windows that
   will be displayed.
 
+* Changed commands
+
+alias [-a] [--] ALIAS = COMMAND [DEFAULT-ARGS...]
+  The alias command can now directly define default-args
+  to prepend to the argument list provided explicitely by the user.
+  For example, to have a backtrace with full details, you can define
+  an alias 'bt_ALL' as
+  'alias bt_ALL = backtrace -entry-values both -frame-arg all
+     -past-main -past-entry -full'.
+  Alias default arguments can also use a set of nested 'with' commands,
+  e.g. 'alias pp10 = with print pretty -- with print elem 10 -- print'
+  defines the alias pp10 that will pretty print a maximum of 10 elements
+  of the given expression (if the expression is an array).
+  See 'set default-args COMMAND [DEFAULT-ARGS...]' for more
+  information about default args concept.
+
 * New targets
 
 GNU/Linux/RISC-V (gdbserver)	riscv*-*-linux*
diff --git a/gdb/doc/gdb.texinfo b/gdb/doc/gdb.texinfo
index 385c832f22..c0fdb25ce2 100644
--- a/gdb/doc/gdb.texinfo
+++ b/gdb/doc/gdb.texinfo
@@ -1577,6 +1577,7 @@  show you the alternatives available, if there is more than one possibility).
 * Command Settings::            How to change default behavior of commands
 * Completion::                  Command completion
 * Command Options::             Command options
+* Command default args::        Automatically prepend default arguments to commands and aliases
 * Help::                        How to ask @value{GDBN} for help
 @end menu
 
@@ -1997,6 +1998,129 @@  uppercase.
 (For more on using the @code{print} command, see @ref{Data, ,Examining
 Data}.)
 
+@node Command default args
+@section Automatically prepend default arguments to commands and aliases
+
+You can tell @value{GDBN} to always prependd some default arguments to
+the list of arguments provided explicitely by the user.
+
+@cindex command options, automatically prepend
+@cindex command, default arguments
+
+@table @code
+@kindex set default-args
+@item set default-args @var{command} [@var{default-args@dots{}}]
+
+If you repeatedly use the same arguments or options for a command,
+you can tell @value{GDBN} to automatically prepend these arguments
+or options to the list of arguments you type explicitely.
+
+For example, if you always want to have the command @code{thread apply all}
+working on the threads in ascending order and to continue in case it
+encounters an error, you can tell @value{GDBN} to automatically preprend
+the @code{-ascending} and @code{-c} options by using:
+
+@smallexample
+(@value{GDBP}) set default-args thread apply all -ascending -c
+@end smallexample
+
+Once you have set these default args, any time you type
+the @code{thread apply all} followed by @code{some arguments},
+@value{GDBN} will execute  @code{thread apply all -ascending -c some arguments}.
+
+As usual, unambiguous abbreviations can be used for @var{command}
+and @var{default-args}.
+
+Commands and their aliases do not share their default args.
+So, for example, you can configure the commands @code{bt}, @code{where},
+@code{backtrace} and @code{info stack} to output different levels
+of information and define a new alias @code{bt_ALL} showing all possible
+information using:
+@smallexample
+(@value{GDBP}) set default-args bt -entry-values no -frame-arguments none
+(@value{GDBP}) set default-args where -entry-values no -frame-argu scalars
+(@value{GDBP}) set default-args backtrace -entry-values no -frame-argu all
+(@value{GDBP}) set default-args info stack -entry-val both -fr all
+(@value{GDBP}) alias bt_ALL = backtrace
+(@value{GDBP}) set default-args bt_ALL -entry-values both -frame-arg all \
+   -past-main -past-entry -full
+@end smallexample
+
+You can define an alias and specify its default args in one command using
+the shorter to type:
+@smallexample
+(@value{GDBP}) alias bt_ALL = backtrace -entry-values both -frame-arg all \
+   -past-main -past-entry -full
+@end smallexample
+(For more on using the @code{alias} command, see @ref{Aliases}.)
+
+Default args are not limited to the arguments and options of @var{command},
+but can specify nested commands if @var{command} accepts such a nested command
+as argument.
+For example, the below defines @code{faalocalsoftype} that can be used to list
+the frames having locals of a certain type, together with the matching local
+vars:
+@smallexample
+(@value{GDBP}) alias faalocalsoftype = frame apply all info locals -q -t
+(@value{GDBP}) faalocalsoftype int
+#1  0x55554f5e in sleeper_or_burner (v=0xdf50) at sleepers.c:86
+i = 0
+ret = 21845
+@end smallexample
+
+This is also very useful to define an alias for a set of nested @code{with}
+commands to have a particular combination of temporary settings.  For example,
+the below defines the alias @code{pp10} that pretty prints an expression
+argument, with a maximum of 10 elements if the expression is a string or
+an array:
+@smallexample
+(@value{GDBP}) alias pp10 = with print pretty -- with print elements 10 -- print
+@end smallexample
+This defines the alias  @code{pp10} as being a sequence of 3 commands.
+The first part @code{with print pretty --} temporarily activates the setting
+@code{set print pretty}, then launches the command that follows the separator
+@code{--}.
+The command following the first part is also a @code{with} command that
+temporarily changes the setting @code{set print elements} to 10, then
+launches the command that follows the second separator @code{--}.
+The third part @code{print} is the command the @code{pp10} alias will launch,
+using the temporary values of the settings and the arguments explicitely given
+by the user.
+For more information about the @code{with} command usage,
+see @ref{Command Settings}.
+
+Use @code{set default-args @var{command}} (without giving @var{default-args})
+to clear the default args of @var{command}.
+
+@item show default-args [@var{command}]
+
+Use @code{show default-args @var{command}} to show the current values of
+the default args for @var{command}.  For example:
+@smallexample
+(@value{GDBP}) show default-args backtrace
+default-args backtrace = -entry-values no -frame-arguments all
+(@value{GDBP}) show default-args break
+default-args break = <no default args>
+@end smallexample
+
+To show all the commands and aliases that have some default args configured,
+use the command
+@code{show default-args} without giving a @var{command} argument. 
+
+@item set enable-default-args @r{[}on|off@r{]}
+@itemx show enable-default-args
+By default, @value{GDBN} will use the configured default args.  This
+can be disabled using @code{set enable-default-args off}.  The default
+args of all commands are not cleared by @code{set enable-default-args
+off}, but will not be used till you do @code{set enable-default-args
+on}.  This can be useful in user defined commands to ensure only the
+specified set of options are used by a command launched by the
+user-defined command.  You can also use this setting in the
+@code{with} command, to temporarily run a command without its possibly
+configured default args.
+
+@end table
+
 @node Help
 @section Getting Help
 @cindex online documentation
@@ -27500,7 +27624,7 @@  You can define a new alias with the @samp{alias} command.
 @table @code
 
 @kindex alias
-@item alias [-a] [--] @var{ALIAS} = @var{COMMAND}
+@item alias [-a] [--] @var{ALIAS} = @var{COMMAND} [DEFAULT-ARGS...]
 
 @end table
 
@@ -27518,6 +27642,19 @@  lists displayed by the @samp{help} command.
 The @samp{--} option specifies the end of options,
 and is useful when @var{ALIAS} begins with a dash.
 
+You can specify @var{default-args} for your alias.
+These @var{default-args} will be automatically added before the alias
+arguments typed explicitely on the command line.
+
+For example, the below defines an alias @code{btfullall} that shows all local
+variables and all frame arguments:
+@smallexample
+(@value{GDBP}) alias btfullall = backtrace -full -frame-arguments all
+@end smallexample
+
+For more information about @var{default-args}, see @ref{Command default args,
+,Automatically prepend default arguments to commands and aliases}
+
 Here is a simple example showing how to make an abbreviation
 of a command so that there is less to type.
 Suppose you were tired of typing @samp{disas}, the current