nuttx/libs/libc/stdio/Kconfig

#
# For a description of the syntax of this configuration file,
# see the file kconfig-language.txt in the NuttX tools repository.
#

menu "Standard C I/O"

config STDIO_DISABLE_BUFFERING
	bool "Disable STDIO Buffering"
	default n
	---help---
		Tiny systems may need to disable all support for I/O buffering in
		order to minimize the memory footprint.

		NOTE that even if STDIO buffering is enabled, you can still disable
		buffering by setting CONFIG_STDIO_BUFFER_SIZE=0 or dynamically
		through the setvbuf() interface.  In this case, however,  memory
		used for buffering will be eliminated, of course, but there will be
		no reduction in static code size.  Only setting
		CONFIG_STDIO_DISABLE_BUFFERING will reduce static code size.

		The setvbuf() interface is not available if
		CONFIG_STDIO_DISABLE_BUFFERING is selected.

if !STDIO_DISABLE_BUFFERING

config STDIO_BUFFER_SIZE
	int "STDIO buffer size"
	default 64
	---help---
		Size of buffers using within the C buffered I/O interfaces (printf,
		putchar, fwrite, etc.).  This function sets the initial I/O buffer
		size.  Zero disables I/O buffering initially.  Any buffer size may
		be subsequently modified using setvbuf().

config STDIO_LINEBUFFER
	bool "STDIO line buffering"
	default y
	---help---
		Sets the default behavior to flush buffered I/O whenever a newline
		character is found in the output data stream.  This setting just
		sets the initial default behavior of all streams.  The behavior of
		an individual stream can be changed via setvbuf().

endif # !STDIO_DISABLE_BUFFERING

config NUNGET_CHARS
	int "Number unget() characters"
	default 2
	---help---
		Number of characters that can be buffered by ungetc() (Only if NFILE_STREAMS > 0)

config LIBC_FLOATINGPOINT
	bool "Enable floating point in printf"
	default n
	---help---
		By default, floating point support in printf, sscanf, etc. is
		disabled.  This option will enable floating point support.

		if CONFIG_NANO_PRINTF is enabled, tnen this option works a
		little differently.  You still have to select
		CONFIG_NANO_PRINTLEVEL=3 to get floating point support.  In
		case, this option extends the range of acceptable
		values that will permit selection of CONFIG_NANO_PRINTLEVEL=3.

config LIBC_LONG_LONG
	bool "Enable long long support in printf"
	default y if !DEFAULT_SMALL
	default n if DEFAULT_SMALL
	---help---
		Enables support for long long formats in printf, sscanf, etc. is
		enabled.  This is enabled by default but if you are trying to
		reduce the FLASH footprint, then disabling this feature is one
		option.  The FLASH saves comes not from disabling the long long
		formats, but rather from omitting the large long long arithmetic
		libraries that will be drawn into the build if long long support
		is enabled.

config LIBC_SCANSET
	bool "Scanset support"
	default n
	---help---
		Add scanset support to sscanf().

choice
	prompt "Newline Options"
	default EOL_IS_EITHER_CRLF
	---help---
		This selection determines the line terminating character that is used.
		Some environments may return CR as end-of-line, others LF, and others
		both.  If not specified, the default is either CR or LF (but not both)
		as the line terminating character.

config EOL_IS_CR
	bool "EOL is CR"

config EOL_IS_LF
	bool "EOL is LF"

config EOL_IS_BOTH_CRLF
	bool "EOL is CR and LF"

config EOL_IS_EITHER_CRLF
	bool "EOL is CR or LF"

endchoice

config MEMCPY_VIK
	bool "Vik memcpy()"
	default n
	depends on !LIBC_ARCH_MEMCPY
	---help---
		Select this option to use the optimized memcpy() function by Daniel Vik.
		Select this option for improved performance at the expense of increased
		size. See licensing information in the top-level COPYING file.

config NANO_PRINTF
	bool "Use nano printf code"
	default y if DEFAULT_SMALL
	default n if !DEFAULT_SMALL
	---help---
		Replace printf code with version from newlib-nano. Can be
		signifcantly smaller, especially if floating support is enabled.
		However, it does not include 'long long' support.

config NANO_PRINTLEVEL
	int "Nano printf support level"
	default 2 if !LIBC_FLOATINGPOINT
	default 3 if LIBC_FLOATINGPOINT
	range 1 2 if !LIBC_FLOATINGPOINT && !LIBC_LONG_LONG
	range 1 3 if LIBC_FLOATINGPOINT && !LIBC_LONG_LONG
	range 2 2 if !LIBC_FLOATINGPOINT && LIBC_LONG_LONG
	range 2 3 if LIBC_FLOATINGPOINT && LIBC_LONG_LONG
	depends on NANO_PRINTF
	---help---
		Nano printf can be built into more than one support level.  The
		default is to offer the usual modifiers and integer formatting
		support (level 2).  Level 1 maintains a minimal version that just
		offers integer formatting, but no modifier support whatsoever.
		Level 3 is intented for floating point support.

endmenu #Standard C I/O