Commit Graph

877 Commits

Author SHA1 Message Date
Masahiro Yamada
fc2694ec1a kconfig: use 'else ifneq' for Makefile to improve readability
'ifeq ... else ifneq ... endif' notation is supported by GNU Make 3.81
or later, which is the requirement for building the kernel since
commit 37d69ee308 ("docs: bump minimal GNU Make version to 3.81").

Use it to improve the readability.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-05-19 09:34:35 +09:00
Alexander Popov
aff11cd983 kconfig: Terminate menu blocks with a comment in the generated config
Currently menu blocks start with a pretty header but end with nothing in
the generated config. So next config options stick together with the
options from the menu block.

Let's terminate menu blocks in the generated config with a comment and
a newline if needed. Example:

...
CONFIG_BPF_STREAM_PARSER=y
CONFIG_NET_FLOW_LIMIT=y

#
# Network testing
#
CONFIG_NET_PKTGEN=y
CONFIG_NET_DROP_MONITOR=y
# end of Network testing
# end of Networking options

CONFIG_HAMRADIO=y
...

Signed-off-by: Alexander Popov <alex.popov@linux.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-05-18 15:31:24 +09:00
Masahiro Yamada
9cc342f6c4 treewide: prefix header search paths with $(srctree)/
Currently, the Kbuild core manipulates header search paths in a crazy
way [1].

To fix this mess, I want all Makefiles to add explicit $(srctree)/ to
the search paths in the srctree. Some Makefiles are already written in
that way, but not all. The goal of this work is to make the notation
consistent, and finally get rid of the gross hacks.

Having whitespaces after -I does not matter since commit 48f6e3cf5b
("kbuild: do not drop -I without parameter").

[1]: https://patchwork.kernel.org/patch/9632347/

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-05-18 11:49:57 +09:00
Masahiro Yamada
9b9f5948af kconfig: make conf_get_autoconfig_name() static
This is only used in confdata.c

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-05-14 23:23:25 +09:00
Jacob Garber
b9d1a8e930 kconfig: use snprintf for formatting pathnames
Valid pathnames will never exceed PATH_MAX, but these file names
are unsanitized and can cause buffer overflow if set incorrectly.
Use snprintf to avoid this. This was flagged during a Coverity scan
of the coreboot project, which also uses kconfig for its build system.

Signed-off-by: Jacob Garber <jgarber1@ualberta.ca>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-05-14 23:23:25 +09:00
Masahiro Yamada
4cb726121e kconfig: remove useless NULL pointer check in conf_write_dep()
conf_write_dep() has just one caller:

    conf_write_dep("include/config/auto.conf.cmd");

"name" always points to a valid string.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-05-14 23:23:16 +09:00
Masahiro Yamada
580c5b3e1b kconfig: make parent directories for the saved .config as needed
With menuconfig / nconfig, users can input any file path from the
"Save" menu, but it fails if the parent directory does not exist.

Why not create the parent directory automatically. I think this is
a user-friendly behavior.

I changed the error messages in menuconfig / nconfig.

"Nonexistent directory" is no longer the most likely reason of the
failure. Perhaps, the user specified the existing directory, or
attempted to write to the location without write permission.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-05-11 02:16:21 +09:00
Masahiro Yamada
67424f61f8 kconfig: do not write .config if the content is the same
Kconfig updates the .config when it exits even if its content is
exactly the same as before. Since its timestamp becomes newer than
that of other build artifacts, additional processing is invoked,
which is annoying.

- syncconfig is invoked to update include/config/auto.conf, etc.

- kernel/configs.o is recompiled if CONFIG_IKCONFIG is enabled,
  then vmlinux is relinked as well.

If the .config is not changed at all, we do not have to even
touch it. Just bail out showing "No change to .config".

  $ make allmodconfig
  scripts/kconfig/conf  --allmodconfig Kconfig
  #
  # configuration written to .config
  #
  $ make allmodconfig
  scripts/kconfig/conf  --allmodconfig Kconfig
  #
  # No change to .config
  #

Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-11 02:15:49 +09:00
Masahiro Yamada
ceb7f3296e kconfig: do not accept a directory for configuration output
Currently, conf_write() can be called with a directory name instead
of a file name. As far as I see, this can happen for menuconfig,
nconfig, gconfig.

If it is given with a directory path, conf_write() kindly appends
getenv("KCONFIG_CONFIG"), but this ends up with hacky dir/basename
handling, and screwed up in corner-cases like "what if KCONFIG_CONFIG
is an absolute path?" as discussed before:

  https://patchwork.kernel.org/patch/9910037/

Since conf_write() is already messed up, I'd say "do not do it".
Please pass a file path all the time. If a directory path is specified
for the configuration output, conf_write() will simply error out.

Now that the tmp file is created in the same directory as the .config,
the previously reported "what if KCONFIG_CONFIG points to a different
file system?" has been solved.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Nicolas Porcel <nicolasporcel06@gmail.com>
2019-05-11 02:14:27 +09:00
Masahiro Yamada
65be755a54 kconfig: remove trailing whitespaces
There are still some trailing whitespaces under scripts/kconfig/tests/,
but they must be kept. Otherwise, "make testconfig" would break.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-05-09 22:37:17 +09:00
Petr Vorel
b63e37bc9e kconfig: Make nconf-cfg.sh executable
Although it's not required for the build *conf-cfg.sh scripts to be
executable (they're run by CONFIG_SHELL), let's be consistent with other
scripts.

Signed-off-by: Petr Vorel <pvorel@suse.cz>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-04-09 22:44:57 +09:00
Changbin Du
9c38f1f044 kconfig/[mn]conf: handle backspace (^H) key
Backspace is not working on some terminal emulators which do not send the
key code defined by terminfo. Terminals either send '^H' (8) or '^?' (127).
But currently only '^?' is handled. Let's also handle '^H' for those
terminals.

Signed-off-by: Changbin Du <changbin.du@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-03-29 22:48:01 +09:00
Masahiro Yamada
c71bb9f866 kconfig: remove stale lxdialog/.gitignore
When this .gitignore was added, lxdialog was an independent hostprogs-y.

Now that all objects in lxdialog/ are directly linked to mconf, the
lxdialog is no longer generated.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-03-17 15:47:02 +09:00
Linus Torvalds
5453a3df2a Kconfig updates for v5.1
- rename lexer and parse files
 
  - fix 'Save as' menu of xconfig
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Merge tag 'kconfig-v5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kconfig updates from Masahiro Yamada:

 - rename lexer and parse files

 - fix 'Save as' menu of xconfig

* tag 'kconfig-v5.1' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  kconfig: fix 'Save As' menu of xconfig
  kconfig: rename zconf.y to parser.y
  kconfig: rename zconf.l to lexer.l
2019-03-13 10:06:28 -07:00
Masahiro Yamada
8741908b3e kconfig: fix 'Save As' menu of xconfig
The 'Save As' menu of xconfig is not working; it always saves the
kernel configuration into the default file irrespective of the file
chosen in the dialog box.

The 'Save' menu always writes into the default file, but it would
make more sense to write into the file previously chosen by 'Load'
or 'Save As'.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-03-12 02:50:24 +09:00
Masahiro Yamada
058507195b kbuild: move ".config not found!" message from Kconfig to Makefile
If you run "make" in a pristine source tree, currently Kbuild will
start to build Kconfig to let it show the error message.

It would be more straightforward to check it in Makefile and let
it fail immediately.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-02-27 22:25:10 +09:00
Masahiro Yamada
769a1c0226 kconfig: rename zconf.y to parser.y
Use a more logical name.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-02-13 23:25:58 +09:00
Masahiro Yamada
981e545a69 kconfig: rename zconf.l to lexer.l
Use a more logical name.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-02-13 23:25:49 +09:00
Masahiro Yamada
2648ca1859 kconfig: clean generated *conf-cfg files
I accidentally dropped '*' in the previous renaming patch.

Revive it so that 'make mrproper' can clean the generated files.

Fixes: d86271af64 ("kconfig: rename generated .*conf-cfg to *conf-cfg")
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-01-14 10:37:09 +09:00
Masahiro Yamada
d86271af64 kconfig: rename generated .*conf-cfg to *conf-cfg
Remove the dot-prefixing since it is just a matter of the
.gitignore file.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-01-06 10:47:09 +09:00
Masahiro Yamada
ba97df4558 kbuild: use assignment instead of define ... endef for filechk_* rules
You do not have to use define ... endef for filechk_* rules.

For simple cases, the use of assignment looks cleaner, IMHO.

I updated the usage for scripts/Kbuild.include in case somebody
misunderstands the 'define ... endif' is the requirement.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2019-01-06 10:22:35 +09:00
Masahiro Yamada
a5003571e6 kconfig: remove unused "file" field of yylval union
This has never been used.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2019-01-06 09:46:51 +09:00
Masahiro Yamada
f222b7f436 kconfig: surround dbg_sym_flags with #ifdef DEBUG to fix gconf warning
Fix the following warning:

  no previous prototype for ‘dbg_sym_flags’ [-Wmissing-prototypes]

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-12-28 22:22:39 +09:00
Masahiro Yamada
3b54197856 kconfig: split images.c out of qconf.cc/gconf.c to fix gconf warnings
Currently, images.c is included by qconf.cc and gconf.c.
qconf.cc uses all of xpm_* arrays, but gconf.c only some of them.
Hence, lots of "... defined but not used" warnings are displayed
while compiling gconf.c

Splitting out images.c fixes the warnings.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-12-28 22:22:39 +09:00
Masahiro Yamada
9abe42371b kconfig: add static qualifiers to fix gconf warnings
Add "static" to functions that are locally used in gconf.c
This fixes some "no previous prototype for ..." warnings.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-12-28 22:22:39 +09:00
Masahiro Yamada
cbafbf7f55 kconfig: split the lexer out of zconf.y
Compile zconf.lex.c independently of the other files.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-12-28 22:22:38 +09:00
Masahiro Yamada
558e78e3ce kconfig: split some C files out of zconf.y
I want to compile each C file independently instead of including all
of them from zconf.y.

Split out confdata.c, expr.c, symbol.c, and preprocess.c .
These are low-hanging fruits.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-12-28 22:22:38 +09:00
Masahiro Yamada
0c87410010 kconfig: convert to SPDX License Identifier
All files in lxdialog/ are licensed under GPL-2.0+, and the rest are
under GPL-2.0. I added GPL-2.0 tags to test scripts in tests/.

Documentation/process/license-rules.rst does not suggest anything
about the flex/bison files. Because flex does not accept the C++
comment style at the very top of a file, I used the C style for
zconf.l, and so for zconf.y for consistency.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-12-28 22:22:28 +09:00
Masahiro Yamada
979f2b2f79 kconfig: remove keyword lookup table entirely
Commit 7a88488bbc ("[PATCH] kconfig: use gperf for kconfig keywords")
introduced gperf for the keyword lookup.

Then, commit bb3290d916 ("Remove gperf usage from toolchain") killed
the gperf use. As a result, the linear keyword search was left behind.

If we do not use gperf, there is no reason to have the separate table
of the keywords. Move all keywords back to the lexer.

I also refactored the lexer to remove the COMMAND and PARAM states.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-12-28 20:44:38 +09:00
Masahiro Yamada
4b31a32caf kconfig: update current_pos in the second lexer
To simplify the generated lexer, let the hand-made lexer update the
file name and line number for the parser.

I tested this with DEBUG_PARSE, and confirmed the same file names
and line numbers were dumped.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-12-22 00:25:56 +09:00
Masahiro Yamada
824fa3b3b5 kconfig: switch to ASSIGN_VAL state in the second lexer
To simplify the generated lexer, switch to the ASSIGN_VAL state in
the hand-made lexer.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-12-22 00:25:55 +09:00
Masahiro Yamada
b3d1d9d3c3 kconfig: stop associating kconf_id with yylval
The lexer has conventionally associated kconf_id data with yylval
to carry additional information to the parser.

No token is relying on this any more.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-12-22 00:25:55 +09:00
Masahiro Yamada
caaebb3c6d kconfig: refactor end token rules
T_ENDMENU, T_ENDCHOICE, T_ENDIF are the last users of kconf_id
associated with yylval. Refactor them to not use it.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-12-22 00:25:54 +09:00
Masahiro Yamada
f5451582c4 kconfig: stop supporting '.' and '/' in unquoted words
In my understanding, special characters such as '.' and '/' are
supported in unquoted words to use bare file paths in the "source"
statement.

With the previous commit surrounding all file paths with double
quotes, we can drop this.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-12-22 00:25:54 +09:00
Masahiro Yamada
171a515d08 kconfig: use T_WORD instead of T_VARIABLE for variables
There is no grammatical ambiguity by using T_WORD for variables.
The parser can distinguish variables from symbols from the context.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-12-22 00:25:53 +09:00
Masahiro Yamada
c3d228713b kconfig: use specific tokens instead of T_ASSIGN for assignments
Currently, the lexer returns T_ASSIGN for all of =, :=, and +=
associating yylval with the flavor.

I want to make the generated lexer as simple as possible. So, the
lexer should convert keywords to tokens without thinking about the
meaning.

   =  ->  T_EQUAL
  :=  ->  T_COLON_EQUAL
  +=  ->  T_PLUS_EQUAL

Unfortunately, Kconfig uses = instead of == for the equal operator.
So, the same token T_EQUAL is used for assignment and comparison.
The parser can still distinguish them from the context.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-12-22 00:25:52 +09:00
Masahiro Yamada
ce2164ab58 kconfig: refactor scanning and parsing "option" properties
For the keywords "modules", "defconfig_list", and "allnoconfig_y",
the lexer should pass specific tokens instead of generic T_WORD.

This simplifies both the lexer and the parser.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-12-22 00:25:52 +09:00
Masahiro Yamada
3c8f317d4c kconfig: use distinct tokens for type and default properties
This commit removes kconf_id::stype to prepare for the entire
removal of kconf_id.c

To simplify the lexer, I want keywords straight-mapped to tokens.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-12-22 00:25:34 +09:00
Masahiro Yamada
a01e5d242d kconfig: remove redundant token defines
These are already defined as %left.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-12-15 17:45:22 +09:00
Masahiro Yamada
4b5ec81bfe kconfig: rename depends_list to comment_option_list
Now the comment_stmt is the only user of depends_list. Rename it to
comment_option_list

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-12-15 17:45:22 +09:00
Masahiro Yamada
1f31be9ec0 kconfig: loosen the order of "visible" and "depends on" in menu entry
Currently, "visible" and "depends on", if defined in a menu entry,
must appear in that order.

The real example is in drivers/media/tuners/Kconfig:

  menu "Customize TV tuners"
          visible if <expr1>
          depends on <expr2>

... is fine, but you cannot change the property order like this:

  menu "Customize TV tuners"
          depends on <expr2>
          visible if <expr1>

Kconfig does not require a specific order of properties. In this case,
menu_add_visibility(() and menu_add_dep() are orthogonal.

Loosen this unreasonable restriction.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-12-15 17:45:21 +09:00
Masahiro Yamada
94d4e1b602 kconfig: remove redundant menu_block rule
The code block surrounded by "menu" ... "endmenu" is stmt_list.

Remove the redundant menu_block symbol entirely.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-12-15 17:45:21 +09:00
Masahiro Yamada
4891796c6f kconfig: remove redundant if_block rule
The code block surrounded by "if" ... "endif" is stmt_list.

Remove the redundant if_block symbol entirely.

Remove "stmt_list: stmt_list end" rule as well since it would
obviously cause conflicts.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-12-15 17:45:21 +09:00
Masahiro Yamada
2f60e46e60 kconfig: remove grammatically ambiguous option_error
This commit decreases 6 shift/reduce conflicts, and finally achieves
conflict-free parser.

Since Kconfig has no terminator for a config block, detecting the end
of config_stmt is not easy.

For example, there are two ways for handling the error in the following
code:

  1 config FOO
  2         =

 [A] Print "unknown option" error, assuming the line 2 is a part of
     config_option_list

 [B] Print "invalid statement", assuming the line 1 is reduced into
     a config_stmt by itself

Bison actually chooses [A] because it performs the shift rather than
the reduction where both are possible.

However, there is no reason to choose one over the other.

Let's remove the option_error, and let it fall back to [B].

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-12-15 17:45:20 +09:00
Masahiro Yamada
6900ae9eee kconfig: remove grammatically ambiguous "unexpected option" diagnostic
This commit decreases 15 shift/reduce conflicts.

The location of this error recovery is ambiguous.

For example, there are two ways to interpret the following code:

  1 config FOO
  2         bool "foo"

 [A] Both lines are reduced together into a config_stmt.

 [B] The only line 1 is reduced into a config_stmt, and the line 2
     matches to "option_name error T_EOL"

Of course, we expect [A], but [B] could be grammatically possible.

Kconfig has no terminator for a config block. So, we cannot detect its
end until we see a non-property keyword. People often insert a blank
line between two config blocks, but it is just a coding convention.
Blank lines are actually allowed anywhere in Kconfig files.

The real error is when a property keyword appears right after "endif",
"endchoice", "endmenu",  "source", "comment", or variable assignment.

Instead of fixing the grammatical ambiguity, I chose to simply remove
this error recovery.

The difference is

  unexpected option "bool"

... is turned into a more generic message:

  invalid statement

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-12-15 17:45:20 +09:00
Masahiro Yamada
723679339d kconfig: warn no new line at end of file
It would be nice to warn if a new line is missing at end of file.

We could do this by checkpatch.pl for arbitrary files, but new line
is rather essential as a statement terminator in Kconfig.

The warning message looks like this:

  kernel/Kconfig.preempt:60:warning: no new line at end of file

Currently, kernel/Kconfig.preempt is the only file with no new line
at end of file. Fix it.

I know there are some false negative cases. For example, no warning
is displayed when the last line contains some whitespaces/comments,
but no new line. Yet, this commit works well for most cases.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-12-15 17:44:35 +09:00
Masahiro Yamada
0bcc547ec4 kconfig: clean up EOF handling in the lexer
A new file should always start in the INITIAL state.

When the lexer bumps into EOF, the lexer must get back to the INITIAL
state anyway. Remove the redundant <<EOF>> pattern in the PARAM state.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-12-13 00:20:09 +09:00
Masahiro Yamada
cc66bca775 kconfig: fix ambiguous grammar in terms of new lines
This commit decreases 8 shift/reduce conflicts.

A certain amount of grammatical ambiguity comes from how to reduce
excessive T_EOL tokens.

Let's take a look at the example code below:

  1  config A
  2          bool "a"
  3
  4          depends on B
  5
  6  config B
  7          def_bool y

The line 3 is melt into "config_option_list", but the line 5 can be
either a part of "config_option_list" or "common_stmt" by itself.

Currently, the lexer converts '\n' to T_EOL verbatim. In Kconfig,
a new line works as a statement terminator, but new lines in empty
lines are not critical since empty lines (or lines that contain only
whitespaces/comments) are just no-op.

If the lexer simply discards no-op lines, the parser will not be
bothered by excessive T_EOL tokens.

Of course, this means we are shifting the complexity from the parser
to the lexer, but it is much easier than tackling on shift/reduce
conflicts.

I introduced the second stage lexer to tweak the behavior.

Discard T_EOL if the previous token is T_EOL or T_HELPTEXT.
Two T_EOL tokens in a row is meaningless. T_HELPTEXT is a special
token that is reduced without T_EOL.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-12-13 00:18:54 +09:00
Masahiro Yamada
21c5ecf604 kconfig: refactor pattern matching in STRING state
Here, similar matching patters are duplicated in order to look ahead
the '\n' character. If the next character is '\n', the lexer returns
T_WORD_QUOTE because it must be prepared to return T_EOL at the next
match.

Use unput('\n') trick to reduce the code duplication.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-12-13 00:16:24 +09:00
Masahiro Yamada
be3c807597 kconfig: remove unneeded pattern matching to whitespaces
Whitespaces are consumed in the COMMAND state anyway.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-12-13 00:16:23 +09:00