Commit Graph

73 Commits

Author SHA1 Message Date
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
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
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
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
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
413cd19d81 kconfig: require T_EOL to reduce visible statement
All line-oriented statements should be reduced when seeing a T_EOL
token. I guess missing T_EOL for the "visible" statement is just a
mistake. This commit decreases one shift/reduce conflict.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-12-13 00:16:22 +09:00
Masahiro Yamada
56869d45e3 kconfig: fix the rule of mainmenu_stmt symbol
The rule of mainmenu_stmt does not have debug print of zconf_lineno(),
but if it had, it would print a wrong line number for the same reason
as commit b2d00d7c61 ("kconfig: fix line numbers for if-entries in
menu tree").

The mainmenu_stmt does not need to eat following empty lines because
they are reduced to common_stmt.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-08-13 12:04:51 +09:00
Dirk Gouders
693359f7ac kconfig: rename SYMBOL_AUTO to SYMBOL_NO_WRITE
Over time, the use of the flag SYMBOL_AUTO changed from initially
marking three automatically generated symbols ARCH, KERNELRELEASE and
UNAME_RELEASE to today's effect of protecting symbols from being
written out.

Currently, only symbols of type CHOICE and those with option
defconf_list set have that flag set.

Reflect that change in semantics in the flag's name.

Signed-off-by: Dirk Gouders <dirk@gouders.net>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-07-18 01:18:09 +09:00
Dirk Gouders
ecd53ac2f2 kconfig: handle P_SYMBOL in print_symbol()
Each symbol has a property of type P_SYMBOL since commit
59e89e3ddf (kconfig: save location of config symbols).
Handle those properties in print_symbol().

Further, place a pointer to print_symbol() in the comment above the
list of known property type.

Signed-off-by: Dirk Gouders <dirk@gouders.net>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-06-28 22:47:47 +09:00
Dirk Gouders
b2d00d7c61 kconfig: fix line numbers for if-entries in menu tree
The line numers for if-entries in the menu tree are off by one or more
lines which is confusing when debugging for correctness of unrelated changes.

According to the git log, commit a02f0570ae (kconfig: improve
error handling in the parser) was the last one that changed that part
of the parser and replaced

	"if_entry: T_IF expr T_EOL"
by
	"if_entry: T_IF expr nl"

but the commit message does not state why this has been done.

When reverting that part of the commit, only the line numers are
corrected (checked with cdebug = DEBUG_PARSE in zconf.y), otherwise
the menu tree remains unchanged (checked with zconfdump() enabled in
conf.c).

An example for the corrected line numbers:

drivers/soc/Kconfig:15:source drivers/soc/tegra/Kconfig
drivers/soc/tegra/Kconfig:4:if
drivers/soc/tegra/Kconfig:6:if

changes to:

drivers/soc/Kconfig:15:source drivers/soc/tegra/Kconfig
drivers/soc/tegra/Kconfig:1:if
drivers/soc/tegra/Kconfig:4:if

Signed-off-by: Dirk Gouders <dirk@gouders.net>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-06-25 23:21:14 +09:00
Masahiro Yamada
1175c02506 kconfig: support simply expanded variable
The previous commit added variable and user-defined function.  They
work similarly in the sense that the evaluation is deferred until
they are used.

This commit adds another type of variable, simply expanded variable,
as we see in Make.

The := operator defines a simply expanded variable, expanding the
righthand side immediately.  This works like traditional programming
language variables.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-05-29 03:31:19 +09:00
Masahiro Yamada
9ced3bddec kconfig: support user-defined function and recursively expanded variable
Now, we got a basic ability to test compiler capability in Kconfig.

config CC_HAS_STACKPROTECTOR
        def_bool $(shell,($(CC) -Werror -fstack-protector -E -x c /dev/null -o /dev/null 2>/dev/null) && echo y || echo n)

This works, but it is ugly to repeat this long boilerplate.

We want to describe like this:

config CC_HAS_STACKPROTECTOR
        bool
        default $(cc-option,-fstack-protector)

It is straight-forward to add a new function, but I do not like to
hard-code specialized functions like that.  Hence, here is another
feature, user-defined function.  This works as a textual shorthand
with parameterization.

A user-defined function is defined by using the = operator, and can
be referenced in the same way as built-in functions.  A user-defined
function in Make is referenced like $(call my-func,arg1,arg2), but I
omitted the 'call' to make the syntax shorter.

The definition of a user-defined function contains $(1), $(2), etc.
in its body to reference the parameters.  It is grammatically valid
to pass more or fewer arguments when calling it.  We already exploit
this feature in our makefiles; scripts/Kbuild.include defines cc-option
which takes two arguments at most, but most of the callers pass only
one argument.

By the way, a variable is supported as a subset of this feature since
a variable is "a user-defined function with zero argument".  In this
context, I mean "variable" as recursively expanded variable.  I will
add a different flavored variable in the next commit.

The code above can be written as follows:

[Example Code]

  success = $(shell,($(1)) >/dev/null 2>&1 && echo y || echo n)
  cc-option = $(success,$(CC) -Werror $(1) -E -x c /dev/null -o /dev/null)

  config CC_HAS_STACKPROTECTOR
          def_bool $(cc-option,-fstack-protector)

[Result]
  $ make -s alldefconfig && tail -n 1 .config
  CONFIG_CC_HAS_STACKPROTECTOR=y

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-05-29 03:31:19 +09:00
Masahiro Yamada
137c0118a9 kconfig: make default prompt of mainmenu less specific
If "mainmenu" is not specified, "Linux Kernel Configuration" is used
as a default prompt.

Given that Kconfig is used in other projects than Linux, let's use
a more generic prompt, "Main menu".

Suggested-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-05-29 03:31:19 +09:00
Masahiro Yamada
96d8e48da5 kconfig: remove string expansion for mainmenu after yyparse()
Now that environments are expanded in the lexer, conf_parse() does
not need to expand them explicitly.

The hack introduced by commit 0724a7c32a ("kconfig: Don't leak
main menus during parsing") can go away.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Ulf Magnusson <ulfalizer@gmail.com>
2018-05-29 03:31:19 +09:00
Masahiro Yamada
104daea149 kconfig: reference environment variables directly and remove 'option env='
To get access to environment variables, Kconfig needs to define a
symbol using "option env=" syntax.  It is tedious to add a symbol entry
for each environment variable given that we need to define much more
such as 'CC', 'AS', 'srctree' etc. to evaluate the compiler capability
in Kconfig.

Adding '$' for symbol references is grammatically inconsistent.
Looking at the code, the symbols prefixed with 'S' are expanded by:
 - conf_expand_value()
   This is used to expand 'arch/$ARCH/defconfig' and 'defconfig_list'
 - sym_expand_string_value()
   This is used to expand strings in 'source' and 'mainmenu'

All of them are fixed values independent of user configuration.  So,
they can be changed into the direct expansion instead of symbols.

This change makes the code much cleaner.  The bounce symbols 'SRCARCH',
'ARCH', 'SUBARCH', 'KERNELVERSION' are gone.

sym_init() hard-coding 'UNAME_RELEASE' is also gone.  'UNAME_RELEASE'
should be replaced with an environment variable.

ARCH_DEFCONFIG is a normal symbol, so it should be simply referenced
without '$' prefix.

The new syntax is addicted by Make.  The variable reference needs
parentheses, like $(FOO), but you can omit them for single-letter
variables, like $F.  Yet, in Makefiles, people tend to use the
parenthetical form for consistency / clarification.

At this moment, only the environment variable is supported, but I will
extend the concept of 'variable' later on.

The variables are expanded in the lexer so we can simplify the token
handling on the parser side.

For example, the following code works.

[Example code]

  config MY_TOOLCHAIN_LIST
          string
          default "My tools: CC=$(CC), AS=$(AS), CPP=$(CPP)"

[Result]

  $ make -s alldefconfig && tail -n 1 .config
  CONFIG_MY_TOOLCHAIN_LIST="My tools: CC=gcc, AS=as, CPP=gcc -E"

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
2018-05-29 03:28:58 +09:00
Sam Ravnborg
694c49a7c0 kconfig: drop localization support
The localization support is broken and appears unused.
There is no google hits on the update-po-config target.
And there is no recent (5 years) activity related to the localization.

So lets just drop this as it is no longer used.

Suggested-by: Ulf Magnusson <ulfalizer@gmail.com>
Suggested-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-05-28 18:25:21 +09:00
Masahiro Yamada
bf0bbdcf10 kconfig: Don't leak choice names during parsing
The named choice is not used in the kernel tree, but if it were used,
it would not be freed.

The intention of the named choice can be seen in the log of
commit 5a1aa8a1af ("kconfig: add named choice group").

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Ulf Magnusson <ulfalizer@gmail.com>
2018-03-02 09:20:55 +09:00
Masahiro Yamada
cd81fc82b9 kconfig: add xstrdup() helper
We already have xmalloc(), xcalloc(), and xrealloc(().  Add xstrdup()
as well to save tedious error handling.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-03-02 00:26:47 +09:00
Ulf Magnusson
1b9eda2e48 kconfig: Warn if help text is blank
Blank help texts are probably either a typo, a Kconfig misunderstanding,
or some kind of half-committing to adding a help text (in which case a
TODO comment would be clearer, if the help text really can't be added
right away).

Best to flag them, IMO.

Example warning:

	drivers/mmc/host/Kconfig:877: warning: 'MMC_TOSHIBA_PCI' defined with blank help text

Signed-off-by: Ulf Magnusson <ulfalizer@gmail.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-02-03 00:02:19 +09:00
Masahiro Yamada
765f4cdef6 kconfig: use default 'yy' prefix for lexer and parser
Flex and Bison provide an option to change the prefix of globally-
visible symbols.  This is useful to link multiple lexers and/or
parsers into the same executable.  However, Kconfig (and any other
host programs in kernel) uses a single lexer and parser.  I do not
see a good reason to change the default 'yy' prefix.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Ulf Magnusson <ulfalizer@gmail.com>
2018-01-22 00:49:31 +09:00
Ulf Magnusson
6479f327de kconfig: Warn if there is more than one help text
Avoids mistakes like in the following real-world example, where only the
final help string ("Say Y...") was used. This particular example was
fixed in commit 561b29e4ec ("media: fix media Kconfig help syntax
issues").

  config DVB_NETUP_UNIDVB
  	...
	select DVB_CXD2841ER if MEDIA_SUBDRV_AUTOSELECT
  	---help---
  	  Support for NetUP PCI express Universal DVB card.
       help
  	Say Y when you want to support NetUP Dual Universal DVB card
        ...

This now prints the following warning:

  drivers/media/pci/netup_unidvb:13: warning: 'DVB_NETUP_UNIDVB' defined with more than one help text -- only the last one will be used

Also free() any extra help strings.

Signed-off-by: Ulf Magnusson <ulfalizer@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-01-22 00:49:29 +09:00
Masahiro Yamada
b92d804a51 kconfig: drop 'boolean' keyword
No more users of this keyword.  Drop it according to the notice by
commit 6341e62b21 ("kconfig: use bool instead of boolean for type
definition attributes").

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Luis R. Rodriguez <mcgrof@kernel.org>
2018-01-22 00:49:29 +09:00
Ulf Magnusson
df60f4b92d kconfig: Remove menu_end_entry()
menu_end_entry() is empty and completely unused as far as I can tell:

	$ git log -G menu_end_entry --oneline
	a02f057 [PATCH] kconfig: improve error handling in the parser
	1da177e Linux-2.6.12-rc2

Last one is the initial Git commit, where menu_end_entry() is empty as
well. I couldn't find anything that redefined it on Google either.

It might be a debugging helper for setting a breakpoint after each
config, menuconfig, and comment is parsed. IMO it hurts more than it
helps in that case by making the parsing code look more complicated at a
glance than it really is, and I suspect it doesn't get used much.

Tested by running the Kconfiglib test suite, which indirectly verifies
that the .config files generated by the C implementation for each
defconfig file in the kernel stays the same.

Signed-off-by: Ulf Magnusson <ulfalizer@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-01-22 00:49:28 +09:00
Ulf Magnusson
0724a7c32a kconfig: Don't leak main menus during parsing
If a 'mainmenu' entry appeared in the Kconfig files, two things would
leak:

	- The 'struct property' allocated for the default "Linux Kernel
	  Configuration" prompt.

	- The string for the T_WORD/T_WORD_QUOTE prompt after the
	  T_MAINMENU token, allocated on the heap in zconf.l.

To fix it, introduce a new 'no_mainmenu_stmt' nonterminal that matches
if there's no 'mainmenu' and adds the default prompt. That means the
prompt only gets allocated once regardless of whether there's a
'mainmenu' statement or not, and managing it becomes simple.

Summary from Valgrind on 'menuconfig' (ARCH=x86) before the fix:

	LEAK SUMMARY:
	   definitely lost: 344,568 bytes in 14,352 blocks
	   ...

Summary after the fix:

	LEAK SUMMARY:
	   definitely lost: 344,440 bytes in 14,350 blocks
	   ...

Signed-off-by: Ulf Magnusson <ulfalizer@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-01-22 00:49:23 +09:00
Ulf Magnusson
bc28fe1d5e kconfig: Don't leak 'option' arguments during parsing
The following strings would leak before this change:

	- option env="LEAKED"
	- option defconfig_list="LEAKED"

These come in the form of T_WORD tokens and are always allocated on the
heap in zconf.l. Free them.

Summary from Valgrind on 'menuconfig' (ARCH=x86) before the fix:

	LEAK SUMMARY:
	   definitely lost: 344,616 bytes in 14,355 blocks
	   ...

Summary after the fix:

	LEAK SUMMARY:
	   definitely lost: 344,568 bytes in 14,352 blocks
	   ...

Signed-off-by: Ulf Magnusson <ulfalizer@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-01-11 01:14:01 +09:00
Ulf Magnusson
24161a6711 kconfig: Don't leak 'source' filenames during parsing
The 'source_stmt' nonterminal takes a 'prompt', which consists of either
a T_WORD or a T_WORD_QUOTE, both of which are always allocated on the
heap in zconf.l and need to have their associated strings freed. Free
them.

The existing code already makes sure to always copy the string, but add
a warning to sym_expand_string_value() to make it clear that the string
must be copied, just in case.

Summary from Valgrind on 'menuconfig' (ARCH=x86) before the fix:

	LEAK SUMMARY:
	   definitely lost: 387,504 bytes in 15,545 blocks
	   ...

Summary after the fix:

	LEAK SUMMARY:
	   definitely lost: 344,616 bytes in 14,355 blocks
	   ...

Signed-off-by: Ulf Magnusson <ulfalizer@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-01-11 01:14:01 +09:00
Ulf Magnusson
26e47a3c11 kconfig: Don't leak symbol names during parsing
Prior to this fix, zconf.y did not free symbol names from zconf.l in
these contexts:

	- After T_CONFIG ('config LEAKED')
	- After T_MENUCONFIG ('menuconfig LEAKED')
	- After T_SELECT ('select LEAKED')
	- After T_IMPLY ('imply LEAKED')
	- After T_DEFAULT in a choice ('default LEAKED')

All of these come in the form of T_WORD tokens, which always have their
associated string allocated on the heap in zconf.l and need to be freed.

Fix by introducing a new nonterminal 'nonconst_symbol' which takes a
T_WORD, fetches the symbol, and then frees the T_WORD string. The
already existing 'symbol' nonterminal works the same way but also
accepts T_WORD_QUOTE, corresponding to a constant symbol. T_WORD_QUOTE
should not be accepted in any of the contexts above, so the 'symbol'
nonterminal can't be reused here.

Fetching the symbol in 'nonconst_symbol' also removes a bunch of
sym_lookup() calls from actions.

Summary from Valgrind on 'menuconfig' (ARCH=x86) before the fix:

	LEAK SUMMARY:
	   definitely lost: 711,571 bytes in 37,756 blocks
	   ...

Summary after the fix:

	LEAK SUMMARY:
	   definitely lost: 387,504 bytes in 15,545 blocks
           ...

Signed-off-by: Ulf Magnusson <ulfalizer@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2018-01-10 23:29:51 +09:00
Ulf Magnusson
c873443430 kconfig: Sync zconf.y with zconf.tab.c_shipped
Looks like a change to a comment in zconf.y was never committed, because
the updated version only appears it zconf.tab.c_shipped. Update the
comment in zconf.y to match.

Signed-off-by: Ulf Magnusson <ulfalizer@gmail.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
2017-12-12 23:56:45 +09:00
Linus Torvalds
bb3290d916 Remove gperf usage from toolchain
It turns out that gperf-3.1 changed types in the generated code in ways
that aren't even trivially detectable without having to generate a test-file.

It's just not worth using tools and libraries from clowns that don't
understand or care about compatibility.  So get rid of gperf.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-08-19 11:02:53 -07:00
Nicolas Pitre
237e3ad0f1 Kconfig: Introduce the "imply" keyword
The "imply" keyword is a weak version of "select" where the target
config symbol can still be turned off, avoiding those pitfalls that come
with the "select" keyword.

This is useful e.g. with multiple drivers that want to indicate their
ability to hook into a secondary subsystem while allowing the user to
configure that subsystem out without also having to unset these drivers.

Currently, the same effect can almost be achieved with:

config DRIVER_A
	tristate

config DRIVER_B
	tristate

config DRIVER_C
	tristate

config DRIVER_D
	tristate

[...]

config SUBSYSTEM_X
	tristate
	default DRIVER_A || DRIVER_B || DRIVER_C || DRIVER_D || [...]

This is unwieldy to maintain especially with a large number of drivers.
Furthermore, there is no easy way to restrict the choice for SUBSYSTEM_X
to y or n, excluding m, when some drivers are built-in. The "select"
keyword allows for excluding m, but it excludes n as well. Hence
this "imply" keyword.  The above becomes:

config DRIVER_A
	tristate
	imply SUBSYSTEM_X

config DRIVER_B
	tristate
	imply SUBSYSTEM_X

[...]

config SUBSYSTEM_X
	tristate

This is much cleaner, and way more flexible than "select". SUBSYSTEM_X
can still be configured out, and it can be set as a module when none of
the drivers are configured in or all of them are modular.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Richard Cochran <richardcochran@gmail.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: John Stultz <john.stultz@linaro.org>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Cc: Paul Bolle <pebolle@tiscali.nl>
Cc: linux-kbuild@vger.kernel.org
Cc: netdev@vger.kernel.org
Cc: Michal Marek <mmarek@suse.com>
Cc: Edward Cree <ecree@solarflare.com>
Link: http://lkml.kernel.org/r/1478841010-28605-2-git-send-email-nicolas.pitre@linaro.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-11-16 09:26:33 +01:00
Jan Beulich
31847b67be kconfig: allow use of relations other than (in)equality
Over the years I found it desirable to be able to use all sorts of
relations, not just (in)equality. And apparently I'm not the only one,
as there's at least one example in the tree where the programmer
assumed this would work (see DEBUG_UART_8250_WORD in
arch/arm/Kconfig.debug). Another possible use would e.g. be to fold the
two SMP/NR_CPUS prompts into one: SMP could be promptless, simply
depending on NR_CPUS > 1.

A (desirable) side effect of this change - resulting from numeric
values now necessarily being compared as numbers rather than as
strings - is that comparing hex values now works as expected: Other
than int ones (which aren't allowed to have leading zeroes), zeroes
following the 0x prefix made them compare unequal even if their values
were equal.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2015-06-15 14:05:58 +02:00
Masahiro Yamada
bb66fc6719 kbuild: trivial - use tabs for code indent where possible
Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2014-06-10 14:00:53 +02:00
Yann E. MORIN
6902dccfda kconfig: do not special-case 'MODULES' symbol
Currently, the 'MODULES' symbol is hard-coded to be the default symbol
that enables/disables tristates, if no other symbol was declared with
'option modules'.

While this used to be needed for the Linux kernel, we now have an
explicit 'option modules' attached to the 'MODULES' symbol (since
cset 11097a036), so we no longer need to special-case it in the
kconfig code.

Furthermore, kconfig is extensively used out of the Linux kernel, and
other projects may have another meaning for a symbol named 'MODULES'.

This patch changes the way we enable/disable tristates: if a symbol was
found with 'option modules' attached to it, then that symbol controls
enabling tristates. Otherwise, tristates are disabled, even if a symbol
named 'MODULES' exists.

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Cc: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Michal Marek <mmarek@suse.cz>
2013-09-05 11:09:17 +02:00
Linus Torvalds
1d3fe4a75b Merge branch 'kconfig' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild-2.6
* 'kconfig' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild-2.6: (25 commits)
  kconfig: Introduce IS_ENABLED(), IS_BUILTIN() and IS_MODULE()
  xconfig: Abort close if configuration cannot be saved
  kconfig: fix missing "0x" prefix from S_HEX symbol in autoconf.h
  kconfig/nconf: remove useless conditionnal
  kconfig/nconf: prevent segfault on empty menu
  kconfig/nconf: use the generic menu_get_ext_help()
  nconfig: Avoid Wunused-but-set warning
  kconfig/conf: mark xfgets() private
  kconfig: remove pending prototypes for kconfig_load()
  kconfig/conf: add command line options' description
  kconfig/conf: reduce the scope of `defconfig_file'
  kconfig: use calloc() for expr allocation
  kconfig: introduce specialized printer
  kconfig: do not overwrite symbol direct dependency in assignment
  kconfig/gconf: silent missing prototype warnings
  kconfig/gconf: kill deadcode
  kconfig: nuke LKC_DIRECT_LINK cruft
  kconfig: nuke reference to SWIG
  kconfig: add missing <stdlib.h> inclusion
  kconfig: add missing <ctype.h> inclusion
  ...

Fix up conflicts in scripts/kconfig/Makefile
2011-07-30 00:17:06 -07:00
Arnaud Lacombe
378dbb2cf5 kconfig: migrate parser to implicit rules
Signed-off-by: Arnaud Lacombe <lacombar@gmail.com>
2011-06-09 14:04:44 -04:00
Arnaud Lacombe
b96a0d0c78 kconfig: kill no longer needed reference to YYDEBUG
Signed-off-by: Arnaud Lacombe <lacombar@gmail.com>
2011-06-09 14:04:43 -04:00