the "CONFIG_" namespace and what's with "CFG_CMD_" prefixes?

[Robert P. J. Day]

  based on some scanning i just did, i notice the following
occurrences of the "CMD_CFG_" prefix on a number of preprocessor
variables:

$ grep -r CFG_CMD *
arch/ppc/mach-mpc5xxx/interrupts.c:#if (CONFIG_COMMANDS & CFG_CMD_IRQ)
arch/ppc/mach-mpc5xxx/ide.c:#ifdef CFG_CMD_IDE
arch/ppc/mach-mpc5xxx/ide.c:#endif /* CFG_CMD_IDE */
arch/ppc/lib/kgdb.c:#endif /* CFG_CMD_KGDB */
board/pcm030/pcm030.c:#if defined (CFG_CMD_IDE) && defined (CONFIG_IDE_RESET)
board/pcm030/pcm030.c:#endif /* defined (CFG_CMD_IDE) && defined (CONFIG_IDE_RESET) */
commands/loads.c:# if (CONFIG_COMMANDS & CFG_CMD_SAVES)
commands/loads.c:# endif /* CFG_CMD_SAVES */
commands/loads.c:#if (CONFIG_COMMANDS & CFG_CMD_SAVES)
commands/loads.c:# endif /* CFG_CMD_SAVES */
commands/loads.c:#if (CONFIG_COMMANDS & CFG_CMD_SAVES)
commands/loads.c:#endif	/* CFG_CMD_SAVES */
common/Kconfig:	  automatically enabled when you select CFG_CMD_DATE .
drivers/net/at91_ether.c:#if defined(CONFIG_MII) || (CONFIG_COMMANDS & CFG_CMD_MII)
drivers/net/at91_ether.c:#endif	/* defined(CONFIG_MII) || (CONFIG_COMMANDS & CFG_CMD_MII) */
drivers/net/at91_ether.c:#if defined(CONFIG_MII) || (CONFIG_COMMANDS & CFG_CMD_MII)
lib/crc32.c:#include <common.h>	/* to get command definitions like CFG_CMD_JFFS2 */
$

  it's not clear what that prefix is supposed to represent since, in
at least one case, it might be a typo -- "CMD_SAVES":

$ grep -r CMD_SAVES *
commands/loads.c:# if (CONFIG_COMMANDS & CFG_CMD_SAVES)
commands/loads.c:# endif /* CFG_CMD_SAVES */
commands/loads.c:#if (CONFIG_COMMANDS & CFG_CMD_SAVES)
commands/loads.c:# endif /* CFG_CMD_SAVES */
commands/loads.c:#if (CONFIG_COMMANDS & CFG_CMD_SAVES)
commands/loads.c:#endif	/* CFG_CMD_SAVES */
commands/Kconfig:config CMD_SAVES
$

  if those tests are meant to match that Kconfig variable, then
obviously they're misspelled.  if not, then i'm not sure what's going
on.  where *are* CFG_CMD_ variables supposed to be defined?  as in:

$ grep -rw CFG_CMD_MII *
drivers/net/at91_ether.c:#if defined(CONFIG_MII) || (CONFIG_COMMANDS & CFG_CMD_MII)
drivers/net/at91_ether.c:#endif	/* defined(CONFIG_MII) || (CONFIG_COMMANDS & CFG_CMD_MII) */
drivers/net/at91_ether.c:#if defined(CONFIG_MII) || (CONFIG_COMMANDS & CFG_CMD_MII)
$

  as a final point, it's standard practise that the "CONFIG_"-prefixed
variable namespace should be reserved *exclusively* for Kconfig
variables.  at least that's the way it works in the kernel world.

  thoughts?

rday
--


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Robert P. J. Day                               Waterloo, Ontario, CANADA

            Linux Consulting, Training and Kernel Pedantry.

Web page:                                          http://crashcourse.ca
Twitter:                                       http://twitter.com/rpjday
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