Re: [PATCH 1/7] PR gdb/15224 "set history filename" to by immediately converted to absolute path

Pedro Alves
2013-05-22T17:51:35Z

On 05/15/2013 11:46 AM, mbilal wrote:

> On Wednesday, May 08, 2013 10:25 PM Pedro wrote:
>> In addition to my previous comments, I realized that this will do the
>>wrong thing with "set history filename ~/foo". Best use tilde_expand
>>and gdb_realpath
>
> 'set history filename ~/foo' is working because following code is doing
> same as you described . I have also attached test case for this.

Ah, good.

> 2013-05-15 Muhammad Bilal <mbilal@codesourcery.com>
>
> PR gdb/15224

It would have been better to file a different PR for this
one, and then making 15224 depend on it. This is a preexisting
bug, after all, that can be triggered no matter what the
default history filename is.

> * top.c (set_history_filename): New function.

This is incomplete. You must have done something with
the new function. :-)

> 2013-05-15 Muhammad Bilal <mbilal@codesourcery.com>
>
> PR gdb/15224
> * gdb.base/setshow.exp: Test 'set history filename' relative
> path.

I think you meant "with a relative path". But this tests more now.
Please make it complete.

> diff --git a/gdb/top.c b/gdb/top.c
> index 480b67e..45b83d7 100644
> --- a/gdb/top.c
> +++ b/gdb/top.c
> @@ -48,6 +48,7 @@
> #include "interps.h"
> #include "observer.h"
> #include "maint.h"
> +#include "filenames.h"
>
> /* readline include files. */
> #include "readline/readline.h"
> @@ -1693,6 +1694,17 @@ show_exec_done_display_p (struct ui_file *file, int from_tty,
> value);
> }
>
> +static void
> +set_history_filename (char *args, int from_tty, struct cmd_list_element *c)
> +{
> + /* We include the current directory so that if the user changes
> + directories the file written will be the same as the one
> + that was read. */
> + if (!IS_ABSOLUTE_PATH (history_filename))
> + history_filename = concat (current_directory, "/", history_filename,
> + (char *) NULL);
> +}

This leaks the previous history_filename. You can use reconcat
instead to address that.

> +
> /* "set" command for the gdb_datadir configuration variable. */
>
> static void
> @@ -1777,7 +1789,7 @@ variable \"HISTSIZE\", or to 256 if this variable is not set."),
> Set the filename in which to record the command history"), _("\
> Show the filename in which to record the command history"), _("\
> (the list of previous commands of which a record is kept)."),
> - NULL,
> + set_history_filename,
> show_history_filename,
> &sethistlist, &showhistlist);
> diff --git a/gdb/testsuite/gdb.base/setshow.exp b/gdb/testsuite/gdb.base/setshow.exp
> index 6d250c0..5345b4b 100644
> --- a/gdb/testsuite/gdb.base/setshow.exp
> +++ b/gdb/testsuite/gdb.base/setshow.exp
> @@ -169,11 +169,24 @@ gdb_test_no_output "set height unlimited"
> gdb_test_no_output "set history expansion on" "set history expansion on"
> #test show history expansion on
> gdb_test "show history expansion on" "History expansion on command input is on.*" "show history expansion"
> +#get home directory path
> +gdb_test_multiple "show environment HOME" "show home directory" {
> + -re "\nHOME = (.*).\n.*$gdb_prompt $" {
> + set HOME $expect_out(1,string)
> + }
> +}
> +#test set history filename ~/foobar.baz
> +gdb_test_no_output "set history filename ~/foobar.baz" \
> + "set history filename ~/foobar.baz"
> +#test show history filename ~/foobar.baz
> +gdb_test "show history filename" "The filename in which to record the command history is \"[file join $HOME foobar.baz]\"..*" \
> + "show history filename ([file join $HOME foobar.baz])"

The gdb_test_multiple above only sets HOME on success. That means this will
explode with an access to an unknown symbol ($HOME) if the gdb_test_multiple
fails.

You can put the result of [file join $HOME foobar.baz] in a
variable and use that, instead of doing that twice:

set filename [file join $HOME foobar.baz]

Actually, "file join" uses the build system's directory separator, but we
want the host's. Actually^2, GDB always uses '/' here, so we can ignore
that and just do:

set filename "$HOME/foobar.baz"

Also,

+gdb_test "show history filename" "The filename in which to record the command history is \"[file join $HOME foobar.baz]\"..*" \
+ "show history filename ([file join $HOME foobar.baz])"

Don't put that "([file join $HOME foobar.baz])" in the gdb.sum message,
as that will make the message depend on system/whoever runs it.

> #test set history filename foobar.baz
> gdb_test_no_output "set history filename foobar.baz" \
> "set history filename foobar.baz"
> #test show history filename foobar.baz
> -gdb_test "show history filename" "The filename in which to record the command history is \"foobar.baz\"..*" "show history filename (foobar.baz)"
> +gdb_test "show history filename" "The filename in which to record the command history is \"[file join [pwd] foobar.baz]\"..*" \
> + "show history filename ([file join [pwd] foobar.baz])"

Another instance of the same problem mentioned before. [pwd]
returns the current working directory on the build machine,
not the host's. Use gdb's "pwd", not tcl's.

As long as we're breaking the long line with a \, please do it
before "The filename" too, so the line ends up a little shorter.

> #test set history save on
> gdb_test_no_output "set history save on" "set history save on"
> #test show history save on
>

--
Pedro Alves