uclibc-ng/extra/Configs/Config.in

#
# For a description of the syntax of this configuration file,
# see extra/config/Kconfig-language.txt
#


menu "General Library Settings"

config DOPIC
	bool "Generate Position Independent Code (PIC)"
	default y
	depends !HAVE_NO_PIC
	help
	  If you wish to build uClibc with support for shared libraries then
	  answer Y here.  If you only want to build uClibc as a static library,
	  then answer N.

config HAVE_SHARED
	bool "Enable support for shared libraries"
	depends on DOPIC
	default y
	help
	  If you wish to build uClibc with support for shared libraries then
	  answer Y here.  If you only want to build uClibc as a static library,
	  then answer N.

config BUILD_UCLIBC_LDSO
	bool "Compile native shared library loader"
	depends on HAVE_SHARED
	default y
	help
	  uClibc has a native shared library loader for some architectures.
	  If you answer Y here, the uClibc native shared library loader will
	  be built for your target architecture.  If this option is available,
	  to you, then you almost certainly want to answer Y.

config FORCE_SHAREABLE_TEXT_SEGMENTS
	bool "Only load shared libraries which can share their text segment"
	depends on BUILD_UCLIBC_LDSO && UCLIBC_COMPLETELY_PIC
	default n
	help
	  If you answer Y here, the uClibc native shared library loader will
	  only load shared libraries, which do not need to modify any non-writable
	  segments. These libraries haven't set the DT_TEXTREL tag in the dynamic
	  section (==> objdump). So all your libraries must be compiled with
	  -fPIC or -fpic, and all assembler function must be written as position
	  independent code (PIC). 
	  Enabling this option will makes uClibc's shared library loader a
	  little bit smaller and guarantee that no memory will be wasted by badly
	  coded shared libraries.

config LDSO_LDD_SUPPORT
	bool "Native shared library loader 'ldd' support"
	depends on BUILD_UCLIBC_LDSO
	default y
	help
	  Enable this to enable all the code needed to support traditional ldd,
	  which executes the shared library loader to resolve all dependencies
	  and then provide a list of shared libraries that are required for an
	  application to function.  Disabling this option will makes uClibc's
	  shared library loader a little bit smaller.  Most people will answer Y.

config UCLIBC_CTOR_DTOR
	bool "Support global constructors and destructors"
	default y
	help
	  If you wish to build uClibc with support for global constructor
	  (ctor) and global destructor (dtor) support, then answer Y here.
	  When ctor/dtor support is enabled, binaries linked with uClibc must
	  also be linked with crtbegin.o and crtend.o which are provided by gcc
	  (the "*startfile:" and "*endfile:" settings in your gcc specs file
	  may need to be adjusted to include these files).  This support will
	  also add a small amount of additional size to each binary compiled vs
	  uClibc.  If you will be using uClibc with C++, or if you need the gcc
	  __attribute__((constructor)) and __attribute__((destructor)) to work,
	  then you definitely want to answer Y here.  If you don't need ctors
	  or dtors and want your binaries to be as small as possible, then
	  answer N.

config UCLIBC_HAS_THREADS
	bool "POSIX Threading Support"
	default y
	help
	  If you want to compile uClibc with pthread support, then answer Y.  
	  This will increase the size of uClibc by adding a bunch of locking
	  to critical data structures, and adding extra code to ensure that
	  functions are properly reentrant.

	  If your applications require pthreads, answer Y.

config UCLIBC_HAS_LFS
	bool "Large File Support"
	default y
	help
	  If you wish to build uClibc with support for accessing large files 
	  (i.e. files greater then 2 GiB) then answer Y.  Do not enable this 
	  if you are using an older Linux kernel (2.0.x) that lacks large file 
	  support.  Enabling this option will increase the size of uClibc.

choice
	prompt "Malloc Implementation"
	default "malloc-930716"
	help
	  "malloc" use mmap for all allocations and so works very well on MMU-less
	  systems that do not support the brk() system call.   It is pretty smart
	  about reusing already allocated memory, and minimizing memory wastage.

	  "malloc-930716" is derived from libc-5.3.12 and uses the brk() system call
	  for all memory allocations.  This makes it very fast.  It is also pretty
	  smart about reusing already allocated memory, and minimizing memory wastage.
	  Because this uses brk() it will not work on uClinux MMU-less systems.

	  If unsure, answer "malloc".

config MALLOC
	bool "malloc"

config MALLOC_930716
	bool "malloc-930716"
	depends on UCLIBC_HAS_MMU

endchoice

config UCLIBC_DYNAMIC_ATEXIT
	bool "Dynamic atexit() Support"
	default y
	help

	  When this option is enabled, uClibc will support an infinite number,
	  of atexit() and on_exit() functions, limited only by your available
	  memory.  This can be important when uClibc is used with C++, since
	  global destructors are implemented via atexit(), and it is quite
	  possible to exceed the default number when this option is disabled.
	  Enabling this option adds a few bytes, and more significantly makes
	  atexit and on_exit depend on malloc, which can be bad when compiling 
	  static executables.

	  Unless you use uClibc with C++, you should probably answer N.


config HAS_SHADOW
	bool "Shadow Password Support"
	default y
	help
	  Answer N if you do not need shadow password support.  
	  Most people will answer Y.

config UCLIBC_HAS_REGEX
	bool "Regular Expression Support"
	default y
	help
	  POSIX regular expression code is really big -- 27k all by itself.
	  If you don't use regular expressions, turn this off and save space.
	  Of course, if you only staticly link, leave this on, since it will
	  only be included in your apps if you use regular expressions.

config UNIX98PTY_ONLY
	bool "Support only Unix 98 PTYs"
	default y
	help
	  If you want to support only Unix 98 PTYs enable this.  Some older
	  applications may need this disabled.  For most current programs, 
	  you can generally answer Y.

config ASSUME_DEVPTS
	bool "Assume that /dev/pts is a devpts or devfs file system"
	default y
	help
	  Enable this if /dev/pts is on a devpts or devfs filesystem.  Both
	  these filesystems automatically manage permissions on the /dev/pts 
	  devices.  You may need to mount your devpts or devfs filesystem on
	  /dev/pts for this to work.

	  Most people should answer Y.

endmenu



menu "Networking Support"

config UCLIBC_HAS_IPV6
	bool "IP version 6 Support"
	default n
	help
	  If you want to include support for the next version of the Internet
	  Protocol (IP version 6) then answer Y.
	  
	  Most people should answer N.

config UCLIBC_HAS_RPC
	bool "Remote Procedure Call (RPC) support"
	default n
	help
	  If you want to include RPC support, enable this.  RPC is rarely used 
	  for anything except for the NFS filesystem.  Unless you plan to use NFS, 
	  you can probably leave this set to N and save some space.  If you need
	  to use NFS then you should answer Y.

config UCLIBC_HAS_FULL_RPC
	bool "Full RPC support"
	depends on UCLIBC_HAS_RPC
	default y if !HAVE_SHARED
	help
	  Normally we enable just enough RPC support for things like rshd and
	  nfs mounts to work.  If you find you need the rest of the RPC stuff, 
	  then enable this option.  Most people can safely answer N.

endmenu


menu "String and Stdio Support"

config UCLIBC_HAS_WCHAR
	bool "Wide Character Support"
	default n
	help
	  Answer Y to enable wide character support.  This will make uClibc 
	  much larger.

	  Most people will answer N.

config UCLIBC_HAS_LOCALE
	bool "Locale Support (experimental/incomplete)"
	depends on UCLIBC_HAS_WCHAR
	default n
	help
	  Answer Y to enable locale support.  This will make uClibc much
	  bigger.  uClibc's locale support is still under development, and
	  should be finished in the next several weeks (November 2002).

	  Most people will wisely answer N.

config USE_OLD_VFPRINTF
	bool "Use the old vfprintf implementation"
	default n
	help
	  Set to true to use the old vfprintf instead of the new.  This is roughly
	  C89 compliant, but doesn't deal with qualifiers on %n and doesn't deal with
	  %h correctly or %hh at all on the integer conversions.  But on i386 it is
	  over 1.5k smaller than the new code.  Of course, the new code fixes the
	  above mentioned deficiencies and adds custom specifier support similar to
	  glibc, as well as handling positional args.  This will be rewritten at some 
	  point to bring it to full C89 standards compliance.

	  Most people will answer N.

endmenu

menu "Library Installation Options"

config SHARED_LIB_LOADER_PATH
	string "Shared library loader path"
	depends on BUILD_UCLIBC_LDSO
	default "$(DEVEL_PREFIX)/lib"
	help
	  When using shared libraries, this path is the location where the
	  shared library will be invoked.  This value will be compiled into
	  every binary compiled with uClibc.

	  BIG FAT WARNING:
	  If you do not have a shared library loader with the correct name
	  sitting in the directory this points to, your binaries will not 
	  run.

config SYSTEM_LDSO
	string "System shared library loader"
	depends on HAVE_SHARED && !BUILD_UCLIBC_LDSO
	default "/lib/ld-linux.so.2"
	help
	  If you are using shared libraries, but do not want/have a native
	  uClibc shared library loader, please specify the name of your
	  target system's shared library loader here...

	  BIG FAT WARNING:
	  If you do not have a shared library loader with the correct name
	  sitting in the directory this points to, your binaries will not 
	  run.

config DEVEL_PREFIX
	string "uClibc development environment directory"
	default "/usr/$(TARGET_ARCH)-linux-uclibc"
	help
	  DEVEL_PREFIX is the directory into which the uClibc development
	  environment will be installed.   The result will look something
	  like the following:
	      $(DEVEL_PREFIX)/
	          lib/            <contains all runtime and static libs>
		  include/        <Where all the header files go>
	  This value is used by the 'make install' Makefile target.  Since this
	  directory is compiled into the uclibc cross compiler spoofer, you
	  have to recompile uClibc if you change this value...

config SYSTEM_DEVEL_PREFIX
	string "uClibc development environment system directory"
	default "$(DEVEL_PREFIX)"
	help
	  SYSTEM_DEVEL_PREFIX is the directory prefix used when installing
	  bin/arch-uclibc-gcc, bin/arch-uclibc-ld, etc.   This is only used by
	  the 'make install' target, and is not compiled into anything.  This
	  defaults to $(DEVEL_PREFIX)/usr, but makers of .rpms and .debs will
	  want to set this to "/usr" instead.

config DEVEL_TOOL_PREFIX
	string "uClibc development environment tool directory"
	default "$(DEVEL_PREFIX)/usr"
	help
	  DEVEL_TOOL_PREFIX is the directory prefix used when installing
	  bin/gcc, bin/ld, etc.   This is only used by the 'make install'
	  target, and is not compiled into anything.  This defaults to
	  $(DEVEL_PREFIX)/usr, but makers of .rpms and .debs may want to
	  set this to something else.

endmenu

menu "uClibc hacking options"

config DODEBUG
	bool "Build uClibc with debugging symbols"
	default n
	help
	  Say Y here if you wish to compile uClibc with debugging symbols.
	  This will allow you to use a debugger to examine uClibc internals
	  while applications are running.  This increases the size of the
	  library considerably and should only be used when doing development.
	  If you are doing development and want to debug uClibc, answer Y.

	  Otherwise, answer N.

config DOASSERTS
	bool "Build uClibc with run-time assertion testing"
	default n
	help
	  Say Y here to include runtime assertion tests.
	  This enables runtime assertion testing in some code, which can
	  increase the size of the library and incur runtime overhead.
	  If you say N, then this testing will be disabled.

config SUPPORT_LD_DEBUG
	bool "Build the shared library loader with debugging support"
	depends on BUILD_UCLIBC_LDSO
	default n
	help
	  Answer Y here to enable all the extra code needed to debug the uClibc
	  native shared library loader.  The level of debugging noise that is
	  generated depends on the LD_DEBUG environment variable...  Just set
	  LD_DEBUG to something like: 'LD_DEBUG=token1,token2,..  prog' to
	  debug your application.  Diagnostic messages will then be printed to
	  the stderr.

	  For now these debugging tokens are available:
	    detail        provide more information for some options
	    move          display copy processing
	    symbols       display symbol table processing
	    reloc         display relocation processing; detail shows the relocation patch
	    nofixups      never fixes up jump relocations
	    bindings      displays the resolve processing (function calls); detail shows the relocation patch
	    all           Enable everything!

	  The additional environment variable:
	    LD_DEBUG_OUTPUT=file
	  redirects the diagnostics to an output file created using
	  the specified name and the process id as a suffix.

	  An excellent start is simply:
	    $ LD_DEBUG=binding,move,symbols,reloc,detail ./appname
	  or to log everything to a file named 'logfile', try this
	    $ LD_DEBUG=all LD_DEBUG_OUTPUT=logfile ./appname

	  If you are doing development and want to debug uClibc's shared library
	  loader, answer Y.  Mere mortals answer N.

config SUPPORT_LD_DEBUG_EARLY
	bool "Build the shared library loader with early debugging support"
	depends on BUILD_UCLIBC_LDSO
	default n
	help
	  Answer Y here to if you find the uClibc shared library loader is
	  crashing or otherwise not working very early on.  This is typical
	  only when starting a new port when you haven't figured out how to
	  properly get the values for argc, argv, environ, etc.  This method
	  allows a degree of visibility into the very early shared library
	  loader initialization process.  If you are doing development and want
	  to debug the uClibc shared library loader early initialization,
	  answer Y.  Mere mortals answer N.

config UCLIBC_MALLOC_DEBUGGING
	bool "Build malloc with debugging support"
	depends MALLOC
	default n
	help
	  Answer Y here to compile extra debugging support code into malloc.
	  Malloc debugging output may then be enabled at runtime using
	  the MALLOC_DEBUG environment variable.  Because this increases
	  the size of malloc appreciably (due to strings etc), you
	  should say N unless you need to debug a malloc problem.

endmenu