Config.in 77 KB

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  1. #
  2. # For a description of the syntax of this configuration file,
  3. # see extra/config/Kconfig-language.txt
  4. #
  5. mainmenu "uClibc-ng $VERSION C Library Configuration"
  6. config DESIRED_TARGET_ARCH
  7. string
  8. option env="ARCH"
  9. config VERSION
  10. string
  11. option env="VERSION"
  12. choice
  13. prompt "Target Architecture"
  14. default TARGET_alpha if DESIRED_TARGET_ARCH = "alpha"
  15. default TARGET_arc if DESIRED_TARGET_ARCH = "arc"
  16. default TARGET_arm if DESIRED_TARGET_ARCH = "arm"
  17. default TARGET_avr32 if DESIRED_TARGET_ARCH = "avr32"
  18. default TARGET_bfin if DESIRED_TARGET_ARCH = "bfin"
  19. default TARGET_cris if DESIRED_TARGET_ARCH = "cris"
  20. default TARGET_frv if DESIRED_TARGET_ARCH = "frv"
  21. default TARGET_h8300 if DESIRED_TARGET_ARCH = "h8300"
  22. default TARGET_hppa if DESIRED_TARGET_ARCH = "hppa"
  23. default TARGET_i386 if DESIRED_TARGET_ARCH = "i386"
  24. default TARGET_ia64 if DESIRED_TARGET_ARCH = "ia64"
  25. default TARGET_lm32 if DESIRED_TARGET_ARCH = "lm32"
  26. default TARGET_m68k if DESIRED_TARGET_ARCH = "m68k"
  27. default TARGET_metag if DESIRED_TARGET_ARCH = "metag"
  28. default TARGET_microblaze if DESIRED_TARGET_ARCH = "microblaze"
  29. default TARGET_mips if DESIRED_TARGET_ARCH = "mips"
  30. default TARGET_nios2 if DESIRED_TARGET_ARCH = "nios2"
  31. default TARGET_or1k if DESIRED_TARGET_ARCH = "or1k"
  32. default TARGET_powerpc if DESIRED_TARGET_ARCH = "powerpc"
  33. default TARGET_sh if DESIRED_TARGET_ARCH = "sh"
  34. default TARGET_sparc if DESIRED_TARGET_ARCH = "sparc"
  35. default TARGET_x86_64 if DESIRED_TARGET_ARCH = "x86_64"
  36. default TARGET_xtensa if DESIRED_TARGET_ARCH = "xtensa"
  37. help
  38. The architecture of your target.
  39. config TARGET_alpha
  40. bool "alpha"
  41. config TARGET_arc
  42. bool "arc"
  43. config TARGET_arm
  44. bool "arm"
  45. config TARGET_avr32
  46. bool "avr32"
  47. config TARGET_bfin
  48. bool "bfin"
  49. # someone could sync this tree:
  50. # http://linux-c6x.org/git/?p=uClibc.git;a=summary
  51. config TARGET_c6x
  52. bool "c6x"
  53. config TARGET_cris
  54. bool "cris"
  55. config TARGET_frv
  56. bool "frv"
  57. config TARGET_h8300
  58. bool "h8300"
  59. config TARGET_hppa
  60. bool "hppa"
  61. config TARGET_i386
  62. bool "i386"
  63. config TARGET_ia64
  64. bool "ia64"
  65. config TARGET_lm32
  66. bool "lm32"
  67. config TARGET_m68k
  68. bool "m68k"
  69. config TARGET_metag
  70. bool "metag"
  71. config TARGET_microblaze
  72. bool "microblaze"
  73. config TARGET_mips
  74. bool "mips"
  75. config TARGET_nios2
  76. bool "nios2"
  77. config TARGET_or1k
  78. bool "or1k"
  79. config TARGET_powerpc
  80. bool "powerpc"
  81. config TARGET_sh
  82. bool "superh"
  83. config TARGET_sparc
  84. bool "sparc"
  85. config TARGET_x86_64
  86. bool "x86_64"
  87. config TARGET_xtensa
  88. bool "xtensa"
  89. endchoice
  90. menu "Target Architecture Features and Options"
  91. if TARGET_alpha
  92. source "extra/Configs/Config.alpha"
  93. endif
  94. if TARGET_arm
  95. source "extra/Configs/Config.arm"
  96. endif
  97. if TARGET_avr32
  98. source "extra/Configs/Config.avr32"
  99. endif
  100. if TARGET_bfin
  101. source "extra/Configs/Config.bfin"
  102. endif
  103. if TARGET_cris
  104. source "extra/Configs/Config.cris"
  105. endif
  106. if TARGET_frv
  107. source "extra/Configs/Config.frv"
  108. endif
  109. if TARGET_h8300
  110. source "extra/Configs/Config.h8300"
  111. endif
  112. if TARGET_hppa
  113. source "extra/Configs/Config.hppa"
  114. endif
  115. if TARGET_i386
  116. source "extra/Configs/Config.i386"
  117. endif
  118. if TARGET_ia64
  119. source "extra/Configs/Config.ia64"
  120. endif
  121. if TARGET_lm32
  122. source "extra/Configs/Config.lm32"
  123. endif
  124. if TARGET_m68k
  125. source "extra/Configs/Config.m68k"
  126. endif
  127. if TARGET_metag
  128. source "extra/Configs/Config.metag"
  129. endif
  130. if TARGET_nios2
  131. source "extra/Configs/Config.nios2"
  132. endif
  133. if TARGET_microblaze
  134. source "extra/Configs/Config.microblaze"
  135. endif
  136. if TARGET_mips
  137. source "extra/Configs/Config.mips"
  138. endif
  139. if TARGET_or1k
  140. source "extra/Configs/Config.or1k"
  141. endif
  142. if TARGET_powerpc
  143. source "extra/Configs/Config.powerpc"
  144. endif
  145. if TARGET_sh
  146. source "extra/Configs/Config.sh"
  147. endif
  148. if TARGET_sparc
  149. source "extra/Configs/Config.sparc"
  150. endif
  151. if TARGET_x86_64
  152. source "extra/Configs/Config.x86_64"
  153. endif
  154. if TARGET_xtensa
  155. source "extra/Configs/Config.xtensa"
  156. endif
  157. if TARGET_c6x
  158. source "extra/Configs/Config.c6x"
  159. endif
  160. if TARGET_arc
  161. source "extra/Configs/Config.arc"
  162. endif
  163. config TARGET_SUBARCH
  164. string
  165. default "e500" if CONFIG_E500
  166. default "classic" if CONFIG_CLASSIC
  167. default "sh4" if CONFIG_SH4
  168. default "sh4" if CONFIG_SH4A
  169. default "" if CONFIG_386
  170. default "i486" if CONFIG_486
  171. default "i586" if CONFIG_586
  172. default "i686" if CONFIG_686
  173. default "arcv2" if CONFIG_ARC_CPU_HS
  174. default ""
  175. source "extra/Configs/Config.in.arch"
  176. endmenu
  177. menu "General Library Settings"
  178. config HAVE_NO_PIC
  179. bool
  180. config DOPIC
  181. bool "Generate only Position Independent Code (PIC)"
  182. default y
  183. depends on !HAVE_NO_PIC
  184. help
  185. If you wish to build all of uClibc as PIC objects, then answer Y here.
  186. If you are unsure, then you should answer N.
  187. config ARCH_HAS_NO_SHARED
  188. bool
  189. config ARCH_HAS_NO_LDSO
  190. bool
  191. select ARCH_HAS_NO_SHARED
  192. config ARCH_HAS_UCONTEXT
  193. bool
  194. config HAVE_SHARED
  195. bool "Enable shared libraries"
  196. depends on !ARCH_HAS_NO_SHARED
  197. default y
  198. help
  199. If you wish to build uClibc with support for shared libraries then
  200. answer Y here. If you only want to build uClibc as a static library,
  201. then answer N.
  202. config FORCE_SHAREABLE_TEXT_SEGMENTS
  203. bool "Only load shared libraries which can share their text segment"
  204. depends on HAVE_SHARED
  205. select DOPIC
  206. help
  207. If you answer Y here, the uClibc native shared library loader will
  208. only load shared libraries, which do not need to modify any
  209. non-writable segments. These libraries haven't set the DT_TEXTREL
  210. tag in the dynamic section (==> objdump).
  211. All your libraries must be compiled with -fPIC or -fpic, and all
  212. assembler function must be written as position independent code (PIC).
  213. Enabling this option will make uClibc's shared library loader a
  214. little bit smaller and guarantee that no memory will be wasted by
  215. badly coded shared libraries.
  216. config LDSO_LDD_SUPPORT
  217. bool "Native 'ldd' support"
  218. depends on HAVE_SHARED
  219. default y
  220. help
  221. Enable all the code needed to support traditional ldd,
  222. which executes the shared library loader to resolve all dependencies
  223. and then provide a list of shared libraries that are required for an
  224. application to function. Disabling this option will make uClibc's
  225. shared library loader a little bit smaller.
  226. Most people will answer Y.
  227. config LDSO_CACHE_SUPPORT
  228. bool "Enable library loader cache (ld.so.conf)"
  229. depends on HAVE_SHARED
  230. default y
  231. help
  232. Enable this to make use of /etc/ld.so.conf, the shared library loader
  233. cache configuration file to support for non-standard library paths.
  234. After updating this file, it is necessary to run 'ldconfig' to update
  235. the /etc/ld.so.cache shared library loader cache file.
  236. config LDSO_PRELOAD_ENV_SUPPORT
  237. bool "Enable library loader LD_PRELOAD environment"
  238. depends on HAVE_SHARED
  239. default y
  240. help
  241. Enable this to make use of LD_PRELOAD environment variable.
  242. A whitespace-separated list of additional, user-specified, ELF shared
  243. libraries to be loaded before all others. This can be used to
  244. selectively override functions in other shared libraries. For
  245. set-user-ID/set-group-ID ELF binaries, only libraries in the standard
  246. search directories that are also set-user-ID will be loaded.
  247. config LDSO_PRELOAD_FILE_SUPPORT
  248. bool "Enable library loader preload file (ld.so.preload)"
  249. depends on HAVE_SHARED
  250. help
  251. Enable this to make use of /etc/ld.so.preload. This file contains a
  252. whitespace separated list of shared libraries to be loaded before
  253. the program.
  254. config LDSO_BASE_FILENAME
  255. string "Shared library loader naming prefix"
  256. depends on HAVE_SHARED && (LDSO_CACHE_SUPPORT || LDSO_PRELOAD_FILE_SUPPORT)
  257. default "ld.so"
  258. help
  259. If you wish to support both uClibc and glibc on the same system, it
  260. is necessary to set this to something other than "ld.so" to avoid
  261. conflicts with glibc, which also uses "ld.so". This prevents both
  262. libraries from using the same /etc/ld.so.* files. If you wish to
  263. support both uClibc and glibc on the same system then you should set
  264. this to "ld-uClibc.so".
  265. Most people will leave this set to the default of "ld.so".
  266. WARNING: Changing the default prefix could cause problems with
  267. binutils' ld !
  268. config LDSO_STANDALONE_SUPPORT
  269. bool "Dynamic linker stand-alone mode support"
  270. depends on HAVE_SHARED
  271. help
  272. The dynamic linker can be run either indirectly through running some
  273. dynamically linked program or library (in which case no command line
  274. options to the dynamic linker can be passed and, in the ELF case, the
  275. dynamic linker which is stored in the .interp section of the program
  276. is executed) or directly by running:
  277. /lib/ld-uClibc.so.* [OPTIONS] [PROGRAM [ARGUMENTS]]
  278. Stand-alone execution is a prerequisite for adding prelink
  279. capabilities to uClibc dynamic linker, as well useful for testing an
  280. updated version of the dynamic linker without breaking the system.
  281. config LDSO_PRELINK_SUPPORT
  282. bool "Dynamic linker prelink support"
  283. depends on HAVE_SHARED
  284. select LDSO_STANDALONE_SUPPORT
  285. help
  286. The dynamic linker can be used in stand-alone mode by the prelink tool
  287. for prelinking ELF shared libraries and binaries to speed up startup
  288. time. It also is able to load and handle prelinked libraries and
  289. binaries at runtime.
  290. config UCLIBC_STATIC_LDCONFIG
  291. bool "Link ldconfig statically"
  292. depends on HAVE_SHARED
  293. default y
  294. help
  295. Enable this option to statically link the ldconfig binary.
  296. Making ldconfig static can be beneficial if you have a library
  297. problem and need to use ldconfig to recover. Sometimes it is
  298. preferable to instead keep the size of the system down, in which
  299. case you should disable this option.
  300. config LDSO_RUNPATH
  301. bool "Enable ELF RUNPATH tag support"
  302. depends on HAVE_SHARED
  303. default y if LDSO_CACHE_SUPPORT
  304. help
  305. ELF's may have dynamic RPATH/RUNPATH tags. These tags list paths
  306. which extend the library search paths. They are really only useful
  307. if a package installs libraries in non standard locations and
  308. ld.so.conf support is disabled.
  309. Usage of RUNPATH tags is not too common, so disabling this feature
  310. should be safe for most people.
  311. config LDSO_RUNPATH_OF_EXECUTABLE
  312. bool "Use executables RUNPATH/RPATH when searching for libraries."
  313. depends on LDSO_RUNPATH
  314. default n
  315. help
  316. Use the executables RUNPATH/RPATH to find to find libraries even
  317. though this behavour is not standard. Setting this option causes
  318. the uclibc dynamic linker behavour to match the glibc dynamic linker.
  319. config LDSO_SAFE_RUNPATH
  320. bool "Allow only RUNPATH beginning with /"
  321. depends on LDSO_RUNPATH
  322. default y
  323. help
  324. Allow only absolute path in RPATH/RUNPATH.
  325. config LDSO_SEARCH_INTERP_PATH
  326. bool "Add ldso path to lib search path"
  327. depends on HAVE_SHARED
  328. default y
  329. help
  330. The ldso is told where it is being executed from and can use that
  331. path to find related core libraries. This is useful by default,
  332. but can be annoying in a mixed development environment.
  333. i.e. if the ldso is run from /foo/boo/ldso.so, it will start its
  334. library search with /foo/boo/
  335. If unsure, simply say Y here.
  336. config LDSO_LD_LIBRARY_PATH
  337. bool "Add LD_LIBRARY_PATH to lib search path"
  338. depends on HAVE_SHARED
  339. default y
  340. help
  341. On hardened system it could be useful to disable the use of
  342. LD_LIBRARY_PATH environment variable (a colon-separated list of
  343. directories in which to search for ELF libraries at execution-time).
  344. If unsure, simply say Y here.
  345. config LDSO_NO_CLEANUP
  346. bool "Disable automatic unloading of dynamically loaded shared objects"
  347. depends on HAVE_SHARED
  348. help
  349. If you need complete allocation traces when debugging memory leaks
  350. using Valgrind in a process that dynamically loads shared objects,
  351. then answer Y here. Unlike glibc, uClibc unloads all dynamically
  352. loaded shared objects when a process exits, which prevents Valgrind
  353. from correctly resolving the symbols from the unloaded shared objects.
  354. Unless you know you need this, you should answer N.
  355. config UCLIBC_CTOR_DTOR
  356. bool
  357. default y
  358. help
  359. If you wish to build uClibc with support for global constructor
  360. (ctor) and global destructor (dtor) support, then answer Y here.
  361. When ctor/dtor support is enabled, binaries linked with uClibc must
  362. also be linked with crtbegin.o and crtend.o which are provided by gcc
  363. (the "*startfile:" and "*endfile:" settings in your gcc specs file
  364. may need to be adjusted to include these files). This support will
  365. also add a small amount of additional size to each binary compiled vs
  366. uClibc. If you will be using uClibc with C++, or if you need the gcc
  367. __attribute__((constructor)) and __attribute__((destructor)) to work,
  368. then you definitely want to answer Y here. If you don't need ctors
  369. or dtors and want your binaries to be as small as possible, then
  370. answer N.
  371. config LDSO_GNU_HASH_SUPPORT
  372. bool "Enable GNU hash style support"
  373. depends on HAVE_SHARED
  374. help
  375. Newest binutils support a new hash style named GNU-hash. The dynamic
  376. linker will use the new GNU-hash section (.gnu.hash) for symbol lookup
  377. if present into the ELF binaries, otherwise it will use the old SysV
  378. hash style (.hash). This ensures that it is completely backward
  379. compatible.
  380. Further, being the hash table implementation self-contained into each
  381. executable and shared libraries, objects with mixed hash style can
  382. peacefully coexist in the same process.
  383. If you want to use this new feature, answer Y
  384. choice
  385. prompt "Thread support"
  386. #default UCLIBC_HAS_THREADS_NATIVE if (TARGET_alpha || TARGET_arm || TARGET_i386 || TARGET_mips || TARGET_powerpc || TARGET_sh || TARGET_sh64)
  387. default HAS_NO_THREADS
  388. help
  389. If you want to compile uClibc with pthread support, then answer Y.
  390. This will increase the size of uClibc by adding a bunch of locking
  391. to critical data structures, and adding extra code to ensure that
  392. functions are properly reentrant.
  393. config HAS_NO_THREADS
  394. bool "none"
  395. help
  396. Disable thread support.
  397. config LINUXTHREADS_OLD
  398. bool "older (stable) version of linuxthreads"
  399. # linuxthreads and linuxthreads.old need nanosleep()
  400. select UCLIBC_HAS_REALTIME
  401. depends on !TARGET_arc && \
  402. !TARGET_arm && \
  403. !TARGET_i386 && \
  404. !TARGET_metag && \
  405. !TARGET_mips && \
  406. !TARGET_powerpc && \
  407. !TARGET_sparc && \
  408. !TARGET_x86_64 && \
  409. !TARGET_xtensa || \
  410. !ARCH_USE_MMU
  411. help
  412. There are two versions of linuxthreads. The older (stable) version
  413. has been in uClibc for quite a long time but hasn't seen too many
  414. updates other than bugfixes.
  415. config LINUXTHREADS_NEW
  416. bool "slightly newer version of linuxthreads"
  417. depends on ARCH_HAS_DEPRECATED_SYSCALLS
  418. depends on !TARGET_arc && \
  419. !TARGET_arm && \
  420. !TARGET_i386 && \
  421. !TARGET_metag && \
  422. !TARGET_mips && \
  423. !TARGET_powerpc && \
  424. !TARGET_sh && \
  425. !TARGET_sparc && \
  426. !TARGET_x86_64 && \
  427. !TARGET_xtensa || \
  428. !ARCH_USE_MMU
  429. help
  430. The new version has not been tested much, and lacks ports for arches
  431. which glibc does not support (like bfin/frv/etc...), but is based on
  432. the latest code from glibc, so it may be the only choice for the
  433. newer ports (like alpha/amd64/64bit arches and hppa).
  434. config UCLIBC_HAS_THREADS_NATIVE
  435. bool "Native POSIX Threading (NPTL)"
  436. select UCLIBC_HAS_TLS
  437. select UCLIBC_HAS_STDIO_FUTEXES
  438. select UCLIBC_HAS_REALTIME
  439. # i386 has no lowlevellock support (yet) as opposed to i486 onward
  440. depends on !CONFIG_386 && \
  441. !TARGET_alpha && \
  442. !TARGET_avr32 && \
  443. !TARGET_bfin && \
  444. !TARGET_c6x && \
  445. !TARGET_cris && \
  446. !TARGET_frv && \
  447. !TARGET_h8300 && \
  448. !TARGET_hppa && \
  449. !TARGET_ia64 && \
  450. !TARGET_m68k && \
  451. !TARGET_microblaze && \
  452. !TARGET_nios2 && \
  453. !TARGET_or1k && \
  454. ARCH_USE_MMU
  455. help
  456. If you want to compile uClibc with NPTL support, then answer Y.
  457. endchoice
  458. config UCLIBC_HAS_THREADS
  459. def_bool y if !HAS_NO_THREADS
  460. config UCLIBC_HAS_TLS
  461. bool "Thread-Local Storage"
  462. depends on UCLIBC_HAS_THREADS_NATIVE
  463. help
  464. If you want to enable TLS support then answer Y.
  465. This is fast an efficient way to store per-thread local data
  466. which is not on stack. It needs __thread support enabled in
  467. gcc.
  468. config PTHREADS_DEBUG_SUPPORT
  469. bool "Build pthreads debugging support"
  470. depends on UCLIBC_HAS_THREADS
  471. help
  472. Say Y here if you wish to be able to debug applications that use
  473. uClibc's pthreads library. By enabling this option, a library
  474. named libthread_db will be built. This library will be dlopen()'d
  475. by gdb and will allow gdb to debug the threads in your application.
  476. IMPORTANT NOTE! Because gdb must dlopen() the libthread_db library,
  477. you must compile gdb with uClibc in order for pthread debugging to
  478. work properly.
  479. If you are doing development and want to debug applications using
  480. uClibc's pthread library, answer Y. Otherwise, answer N.
  481. config UCLIBC_HAS_SYSLOG
  482. bool "Syslog support"
  483. default y
  484. depends on UCLIBC_HAS_NETWORK_SUPPORT
  485. select UCLIBC_HAS_SOCKET
  486. help
  487. Support sending messages to the system logger.
  488. This requires socket-support.
  489. config UCLIBC_HAS_LFS
  490. bool "Large File Support"
  491. default y
  492. help
  493. If you wish to build uClibc with support for accessing large files
  494. (i.e. files greater then 2 GiB) then answer Y. Do not enable this
  495. if you are using an older Linux kernel (2.0.x) that lacks large file
  496. support. Enabling this option will increase the size of uClibc.
  497. choice
  498. prompt "Malloc Implementation"
  499. default MALLOC if ! ARCH_USE_MMU
  500. default MALLOC_STANDARD if ARCH_USE_MMU
  501. config MALLOC
  502. bool "malloc"
  503. help
  504. "malloc" use mmap for all allocations and so works very well on
  505. MMU-less systems that do not support the brk() system call. It is
  506. pretty smart about reusing already allocated memory, and minimizing
  507. memory wastage.
  508. This is the default for uClinux MMU-less systems.
  509. config MALLOC_SIMPLE
  510. bool "malloc-simple"
  511. help
  512. "malloc-simple" is trivially simple and slow as molasses. It
  513. was written from scratch for uClibc, and is the simplest possible
  514. (and therefore smallest) malloc implementation.
  515. This uses only the mmap() system call to allocate and free memory,
  516. and does not use the brk() system call at all, making it a fine
  517. choice for MMU-less systems with very limited memory. It's 100%
  518. standards compliant, thread safe, very small, and releases freed
  519. memory back to the OS immediately rather than keeping it in the
  520. process's heap for reallocation. It is also VERY SLOW.
  521. config MALLOC_STANDARD
  522. bool "malloc-standard"
  523. depends on ARCH_USE_MMU
  524. help
  525. "malloc-standard" is derived from the public domain dlmalloc
  526. implementation by Doug Lea. It is quite fast, and is pretty smart
  527. about reusing already allocated memory, and minimizing memory
  528. wastage. This uses brk() for small allocations, while using mmap()
  529. for larger allocations. This is the default malloc implementation
  530. for uClibc.
  531. If unsure, answer "malloc-standard".
  532. endchoice
  533. config MALLOC_GLIBC_COMPAT
  534. bool "Malloc returns live pointer for malloc(0)"
  535. help
  536. The behavior of malloc(0) is listed as implementation-defined by
  537. SuSv3. Glibc returns a valid pointer to something, while uClibc
  538. normally returns NULL. I personally feel glibc's behavior is
  539. not particularly safe, and allows buggy applications to hide very
  540. serious problems.
  541. When this option is enabled, uClibc will act just like glibc, and
  542. return a live pointer when someone calls malloc(0). This pointer
  543. provides a malloc'ed area with a size of 1 byte. This feature is
  544. mostly useful when dealing with applications using autoconf's broken
  545. AC_FUNC_MALLOC macro (which redefines malloc as rpl_malloc if it
  546. does not detect glibc style returning-a-valid-pointer-for-malloc(0)
  547. behavior). Most people can safely answer N.
  548. config UCLIBC_HAS_OBSTACK
  549. bool "Obstack Support (gnu extension)"
  550. help
  551. When this option is enabled, uClibc will provide support for obstacks.
  552. An obstack is a structure in which memory can be dynamically allocated
  553. as a 'stack of objects'. Many programs need this GNU extention and
  554. you should say Y if you are using any. Otherwise, say N to save some
  555. space.
  556. config UCLIBC_DYNAMIC_ATEXIT
  557. bool "Dynamic atexit() Support"
  558. default y
  559. help
  560. When this option is enabled, uClibc will support an infinite number,
  561. of atexit() and on_exit() functions, limited only by your available
  562. memory. This can be important when uClibc is used with C++, since
  563. global destructors are implemented via atexit(), and it is quite
  564. possible to exceed the default number when this option is disabled.
  565. Enabling this option adds a few bytes, and more significantly makes
  566. atexit and on_exit depend on malloc, which can be bad when compiling
  567. static executables.
  568. Unless you use uClibc with C++, you should probably answer N.
  569. config COMPAT_ATEXIT
  570. bool "Old (visible) atexit Support"
  571. help
  572. Enable this option if you want to update from 0.9.28 to git/0.9.29,
  573. else you will be missing atexit() until you rebuild all apps.
  574. config UCLIBC_HAS_UTMPX
  575. bool "utmpx based support for tracking login/logouts to/from the system"
  576. help
  577. Answer y to enable support for accessing user accounting database.
  578. It can be used to track all login/logout to the system.
  579. config UCLIBC_HAS_UTMP
  580. bool "utmp support (XPG2 compat, SVr4 compat)"
  581. depends on UCLIBC_HAS_UTMPX
  582. help
  583. Answer y to enable legacy SVID support for accessing
  584. user accounting database:
  585. getutent(), getutid(), getutline(), pututline(),
  586. setutent(), endutent(), utmpname() in utmp.h
  587. It can be used to track all login/logout to the system.
  588. If unsure, answer N and use corresponding POSIX functions
  589. from utmpx.h
  590. config UCLIBC_SUSV2_LEGACY
  591. bool "Enable SuSv2 LEGACY functions"
  592. help
  593. Enable this option if you want to have SuSv2 LEGACY functions
  594. Currently applies to:
  595. valloc
  596. WARNING! ABI incompatibility.
  597. config UCLIBC_SUSV3_LEGACY
  598. bool "Enable SuSv3 LEGACY functions"
  599. #vfork,
  600. # h_errno
  601. # gethostbyaddr
  602. # gethostbyname
  603. help
  604. Enable this option if you want to have SuSv3 LEGACY functions
  605. in the library, else they are replaced by SuSv3 proposed macros.
  606. Currently applies to:
  607. bcmp, bcopy, bzero, index, rindex, ftime,
  608. bsd_signal, (ecvt), (fcvt), gcvt, (getcontext),
  609. (getwd), (makecontext),
  610. mktemp, (pthread_attr_getstackaddr), (pthread_attr_setstackaddr),
  611. scalb, (setcontext), (swapcontext), ualarm, usleep,
  612. wcswcs.
  613. WARNING! ABI incompatibility.
  614. config UCLIBC_HAS_CONTEXT_FUNCS
  615. bool "Use obsolescent context control functions"
  616. depends on UCLIBC_SUSV3_LEGACY && ARCH_HAS_UCONTEXT
  617. help
  618. Add into library the SuSv3 obsolescent functions used for context
  619. control. The setcontext family allows the implementation in C of
  620. advanced control flow patterns such as iterators, fibers, and
  621. coroutines. They may be viewed as an advanced version of
  622. setjmp/longjmp; whereas the latter allows only a single non-local jump
  623. up the stack, setcontext allows the creation of multiple cooperative
  624. threads of control, each with its own stack.
  625. These functions are: setcontext, getcontext, makecontext, swapcontext.
  626. config UCLIBC_SUSV3_LEGACY_MACROS
  627. bool "Enable SuSv3 LEGACY macros"
  628. help
  629. Enable this option if you want to have SuSv3 LEGACY macros.
  630. Currently applies to bcopy/bzero/bcmp/index/rindex et al.
  631. WARNING! ABI incompatibility.
  632. config UCLIBC_SUSV4_LEGACY
  633. bool "Enable SuSv4 LEGACY or obsolescent functions"
  634. help
  635. Enable this option if you want to have SuSv4 LEGACY functions
  636. and macros in the library.
  637. Currently applies to:
  638. - XSI functions:
  639. _longjmp, _setjmp, _tolower, _toupper, ftw, getitimer,
  640. gettimeofday, isascii, pthread_getconcurrency,
  641. pthread_setconcurrency, setitimer, setpgrp, sighold,
  642. sigignore, sigpause, sigrelse, sigset, siginterrupt,
  643. tempnam, toascii, ulimit.
  644. - Base functions:
  645. asctime, asctime_r, ctime, ctime_r, gets, rand_r,
  646. tmpnam, utime.
  647. WARNING! ABI incompatibility.
  648. config UCLIBC_STRICT_HEADERS
  649. bool "Hide structures and constants for unsupported features"
  650. help
  651. Hide structures and constants in headers that should not be used,
  652. because the respective feature is disabled.
  653. WARNING! enabling this option requires to patch many faulty apps,
  654. since they make (wrongly) use of these structures/constants,
  655. although the feature was disabled.
  656. config UCLIBC_HAS_STUBS
  657. bool "Provide stubs for unavailable functionality"
  658. help
  659. With this option uClibc provides non-functional stubs for
  660. functions which are impossible to implement on the target
  661. architecture. Otherwise, such functions are simply omitted.
  662. config UCLIBC_HAS_SHADOW
  663. bool "Shadow Password Support"
  664. default y
  665. help
  666. Answer N if you do not need shadow password support.
  667. Most people will answer Y.
  668. config UCLIBC_HAS_PROGRAM_INVOCATION_NAME
  669. bool "Support for program_invocation_name"
  670. help
  671. Support for the GNU-specific program_invocation_name and
  672. program_invocation_short_name strings. Some GNU packages
  673. (like tar and coreutils) utilize these for extra useful
  674. output, but in general are not required.
  675. At startup, these external strings are automatically set
  676. up based on the value of ARGV[0].
  677. If unsure, just answer N.
  678. config UCLIBC_HAS___PROGNAME
  679. bool "Support for __progname"
  680. default y
  681. help
  682. Some packages (like openssh) like to peek into internal libc
  683. symbols to make their output a bit more user friendly.
  684. At startup, __progname is automatically set up based on the
  685. value of ARGV[0].
  686. If unsure, just answer N.
  687. config UCLIBC_HAS_PTY
  688. bool "Support for pseudo-terminals"
  689. default y
  690. help
  691. This enables support for pseudo-terminals (see man 4 pts
  692. and man 7 pty).
  693. If unsure, just answer Y.
  694. config ASSUME_DEVPTS
  695. bool "Assume that /dev/pts is a devpts or devfs file system"
  696. default y
  697. depends on UCLIBC_HAS_PTY
  698. help
  699. Enable this if /dev/pts is on a devpts or devfs filesystem. Both
  700. these filesystems automatically manage permissions on the /dev/pts
  701. devices. You may need to mount your devpts or devfs filesystem on
  702. /dev/pts for this to work.
  703. Most people should answer Y.
  704. config UNIX98PTY_ONLY
  705. bool "Support only Unix 98 PTYs"
  706. default y
  707. depends on UCLIBC_HAS_PTY
  708. help
  709. If you want to support only Unix 98 PTYs enable this. Some older
  710. applications may need this disabled and will thus use legacy BSD
  711. style PTY handling which is more complex and also bigger than
  712. Unix 98 PTY handling.
  713. For most current programs, you can generally answer Y.
  714. if UNIX98PTY_ONLY
  715. config UCLIBC_HAS_GETPT
  716. bool "Support getpt() (glibc-compat)"
  717. depends on UCLIBC_HAS_PTY
  718. help
  719. Some packages may need getpt().
  720. All of those are non-standard and can be considered
  721. GNU/libc compatibility.
  722. Either use posix_openpt() or just open /dev/ptmx yourself.
  723. If unsure, just say N.
  724. endif
  725. if !UNIX98PTY_ONLY
  726. # Have to use __libc_ptyname{1,2}[] and related bloat
  727. config UCLIBC_HAS_GETPT
  728. def_bool y
  729. endif
  730. config UCLIBC_HAS_LIBUTIL
  731. bool "Provide libutil library and functions"
  732. depends on UCLIBC_HAS_PTY
  733. help
  734. Provide a libutil library.
  735. This non-standard conforming library provides the following
  736. utility functions:
  737. forkpty(): combines openpty(), fork(2), and login_tty() to
  738. create a new process operating in a pseudo-terminal.
  739. login(): write utmp and wtmp entries
  740. login_tty(): prepares for a login on the tty fd by creating a
  741. new session, making fd the controlling terminal for
  742. the calling process, setting fd to be the standard
  743. input, output, and error streams of the current
  744. process, and closing fd.
  745. logout(): write utmp and wtmp entries
  746. logwtmp(): constructs a utmp structure and calls updwtmp() to
  747. append the structure to the utmp file.
  748. openpty(): finds an available pseudo-terminal and returns
  749. file descriptors for the master and slave
  750. This library adds about 3k-4k to your system.
  751. config UCLIBC_HAS_TM_EXTENSIONS
  752. bool "Support 'struct tm' timezone extension fields"
  753. default y
  754. help
  755. Enabling this option adds fields to 'struct tm' in time.h for
  756. tracking the number of seconds east of UTC, and an abbreviation for
  757. the current timezone. These fields are not specified by the SuSv3
  758. standard, but they are commonly used in both GNU and BSD application
  759. code.
  760. To strictly follow the SuSv3 standard, leave this disabled.
  761. Most people will probably want to answer Y.
  762. config UCLIBC_HAS_TZ_CACHING
  763. bool "Enable caching of the last valid timezone 'TZ' string"
  764. default y
  765. help
  766. Answer Y to enable caching of the last valid 'TZ' string describing
  767. the timezone setting. This allows a quick string compare to avoid
  768. repeated parsing of unchanged 'TZ' strings when tzset() is called.
  769. Most people will answer Y.
  770. config UCLIBC_HAS_TZ_FILE
  771. bool "Enable '/etc/TZ' file support to set a default timezone (uClibc-specific)"
  772. default y
  773. help
  774. Answer Y to enable the setting of a default timezone for uClibc.
  775. Ordinarily, uClibc gets the timezone information exclusively from the
  776. 'TZ' environment variable. In particular, there is no support for
  777. the zoneinfo directory tree or the /etc/timezone file used by glibc.
  778. With this option enabled, uClibc will use the value stored in the
  779. file '/etc/TZ' (default path) to obtain timezone information if the
  780. 'TZ' environment variable is missing or has an invalid value. The
  781. file consists of a single line (newline required) of text describing
  782. the timezone in the format specified for the TZ environment variable.
  783. Doing 'echo CST6CDT > /etc/TZ' is enough to create a valid file.
  784. See
  785. http://www.opengroup.org/onlinepubs/007904975/basedefs/xbd_chap08.html
  786. for details on valid settings of 'TZ'.
  787. Most people will answer Y.
  788. config UCLIBC_HAS_TZ_FILE_READ_MANY
  789. bool "Repeatedly read the '/etc/TZ' file"
  790. depends on UCLIBC_HAS_TZ_FILE
  791. default y
  792. help
  793. Answer Y to enable repeated reading of the '/etc/TZ' file even after
  794. a valid value has been read. This incurs the overhead of an
  795. open/read/close for each tzset() call (explicit or implied). However,
  796. setting this will allow applications to update their timezone
  797. information if the contents of the file change.
  798. Most people will answer Y.
  799. config UCLIBC_TZ_FILE_PATH
  800. string "Path to the 'TZ' file for setting the global timezone"
  801. depends on UCLIBC_HAS_TZ_FILE
  802. default "/etc/TZ"
  803. help
  804. This is the path to the 'TZ' file.
  805. Most people will use the default of '/etc/TZ'.
  806. config UCLIBC_FALLBACK_TO_ETC_LOCALTIME
  807. bool "Use /etc/localtime as a fallback"
  808. depends on UCLIBC_HAS_TZ_FILE
  809. default y
  810. help
  811. Answer Y to try to use /etc/localtime file.
  812. On glibc systems this file (if it is in TZif2 format)
  813. contains timezone string at the end.
  814. Most people will answer Y.
  815. endmenu
  816. menu "Advanced Library Settings"
  817. config UCLIBC_PWD_BUFFER_SIZE
  818. int "Buffer size for getpwnam() and friends"
  819. default 256
  820. range 12 1024
  821. help
  822. This sets the value of the buffer size for getpwnam() and friends.
  823. By default, this is 256. (For reference, glibc uses 1024).
  824. The value can be found using sysconf() with the _SC_GETPW_R_SIZE_MAX
  825. parameter.
  826. config UCLIBC_GRP_BUFFER_SIZE
  827. int "Buffer size for getgrnam() and friends"
  828. default 256
  829. range 12 1024
  830. help
  831. This sets the value of the buffer size for getgrnam() and friends.
  832. By default, this is 256. (For reference, glibc uses 1024).
  833. The value can be found using sysconf() with the _SC_GETGR_R_SIZE_MAX
  834. parameter.
  835. comment "Support various families of functions"
  836. config UCLIBC_LINUX_MODULE_26
  837. bool "Linux kernel module functions (2.6)"
  838. default y
  839. help
  840. delete_module, init_module
  841. are used in linux for loadable kernel modules.
  842. Say N if you do not use kernel modules.
  843. config UCLIBC_LINUX_MODULE_24
  844. bool "Linux kernel module functions (<2.6)"
  845. depends on !TARGET_bfin && !TARGET_c6x
  846. help
  847. create_module, query_module
  848. are used in linux (prior to 2.6) for loadable kernel modules.
  849. Say N if you do not use kernel modules, or you only support
  850. Linux 2.6+.
  851. config UCLIBC_LINUX_SPECIFIC
  852. bool "Linux specific functions"
  853. default y
  854. help
  855. accept4(), bdflush(),
  856. capget(), capset(), eventfd(), fallocate(),
  857. fstatfs(), getrandom(), inotify_*(), ioperm(), iopl(),
  858. madvise(), modify_ldt(), pipe2(), personality(),
  859. prctl()/arch_prctl(), pivot_root(), modify_ldt(),
  860. ppoll(), readahead(), reboot(), remap_file_pages(),
  861. sched_getaffinity(), sched_setaffinity(), sendfile(),
  862. setfsgid(), setfsuid(), setresgid(), setresuid(),
  863. splice(), vmsplice(), tee(), signalfd(), statfs(),
  864. swapoff(), swapon(), sync_file_range(), syncfs(),
  865. _sysctl(), sysinfo(), timerfd_*(), vhangup(), umount(),
  866. umount2()
  867. config UCLIBC_HAS_GNU_ERROR
  868. bool "Support GNU extensions for error-reporting"
  869. default y
  870. help
  871. Support for the GNU-specific error(), error_at_line(),
  872. void (* error_print_progname)(), error_message_count
  873. functions and variables. Some GNU packages
  874. utilize these for extra useful output, but in general
  875. are not required.
  876. If unsure, just answer N.
  877. config UCLIBC_BSD_SPECIFIC
  878. bool "BSD specific functions"
  879. default y
  880. help
  881. mincore(), getdomainname(), setdomainname()
  882. If unsure, say N.
  883. config UCLIBC_HAS_BSD_ERR
  884. bool "BSD err functions"
  885. default y
  886. help
  887. These functions are non-standard BSD extensions.
  888. err(), errx(), warn(), warnx(), verr(), verrx(), vwarn(), vwarnx()
  889. If unsure, say N.
  890. config UCLIBC_HAS_OBSOLETE_BSD_SIGNAL
  891. bool "BSD obsolete signal functions"
  892. help
  893. These functions are provided as a compatibility interface for
  894. programs that make use of the historical System V signal API.
  895. This API is obsolete:
  896. new applications should use the POSIX signal API (sigaction(2),
  897. sigprocmask(2), etc.).
  898. Affected functions:
  899. sigset(), sighold(), sigrelse(), sigignore()
  900. If unsure, say N.
  901. config UCLIBC_HAS_OBSOLETE_SYSV_SIGNAL
  902. bool "SYSV obsolete signal functions"
  903. help
  904. Use of sysv_signal() should be avoided; use sigaction(2) instead.
  905. If unsure, say N.
  906. config UCLIBC_NTP_LEGACY
  907. bool "ntp_*() aliases"
  908. help
  909. Provide legacy aliases for ntp functions:
  910. ntp_adjtime(), ntp_gettime()
  911. It is safe to say N here.
  912. config UCLIBC_SV4_DEPRECATED
  913. bool "Enable SVr4 deprecated functions"
  914. help
  915. These functions are DEPRECATED in System V release 4.
  916. Say N unless you desparately need one of the functions below:
  917. ustat() [use statfs(2) in your code instead]
  918. config UCLIBC_HAS_REALTIME
  919. bool "Realtime-related family of SUSv functions"
  920. default y
  921. help
  922. These functions are part of the Timers option and need not
  923. be available on all implementations.
  924. Includes AIO, message-queue, scheduler, semaphore functions:
  925. aio.h
  926. mqueue.h
  927. sched.h
  928. semaphore.h
  929. aio_cancel()
  930. aio_error()
  931. aio_fsync()
  932. aio_read()
  933. lio_listio()
  934. aio_return()
  935. aio_suspend()
  936. aio_write()
  937. clock_getres(), clock_gettime(), clock_settime()
  938. fdatasync()
  939. mlockall(), munlockall()
  940. mlock(), munlock()
  941. mq_close()
  942. mq_getattr()
  943. mq_notify()
  944. mq_open()
  945. mq_receive()
  946. mq_send()
  947. mq_setattr()
  948. mq_unlink()
  949. nanosleep()
  950. sched_getparam()
  951. sched_get_priority_max(), sched_get_priority_min()
  952. sched_getscheduler()
  953. sched_rr_get_interval()
  954. sched_setparam()
  955. sched_setscheduler()
  956. sem_close()
  957. sem_destroy()
  958. sem_getvalue()
  959. sem_init()
  960. sem_open()
  961. sem_post()
  962. sem_trywait(), sem_wait()
  963. sem_unlink()
  964. sigqueue()
  965. sigtimedwait(), sigwaitinfo()
  966. timer_create()
  967. timer_delete()
  968. timer_getoverrun(), timer_gettime(), timer_settime()
  969. config UCLIBC_HAS_ADVANCED_REALTIME
  970. bool "Advanced realtime-related family of SUSv functions"
  971. default y
  972. depends on UCLIBC_HAS_REALTIME
  973. help
  974. These functions are part of the Timers option and need not
  975. be available on all implementations.
  976. clock_getcpuclockid()
  977. clock_nanosleep()
  978. mq_timedreceive()
  979. mq_timedsend()
  980. posix_fadvise()
  981. posix_fallocate()
  982. posix_madvise()
  983. posix_memalign()
  984. posix_mem_offset()
  985. posix_spawnattr_destroy(), posix_spawnattr_init()
  986. posix_spawnattr_getflags(), posix_spawnattr_setflags()
  987. posix_spawnattr_getpgroup(), posix_spawnattr_setpgroup()
  988. posix_spawnattr_getschedparam(), posix_spawnattr_setschedparam()
  989. posix_spawnattr_getschedpolicy(), posix_spawnattr_setschedpolicy()
  990. posix_spawnattr_getsigdefault(), posix_spawnattr_setsigdefault()
  991. posix_spawnattr_getsigmask(), posix_spawnattr_setsigmask()
  992. posix_spawn_file_actions_addclose()
  993. posix_spawn_file_actions_adddup2()
  994. posix_spawn_file_actions_addopen()
  995. posix_spawn_file_actions_destroy()
  996. posix_spawn_file_actions_init()
  997. posix_spawn()
  998. posix_spawnp()
  999. posix_typed_mem_get_info()
  1000. pthread_mutex_timedlock()
  1001. sem_timedwait()
  1002. #config UCLIBC_HAS_TERMIOS
  1003. # bool "termios functions"
  1004. # default y
  1005. # help
  1006. # Get and set terminal attributes, line control, get and set baud
  1007. # rate.
  1008. # termios(), tcgetattr(), tcsetattr(), tcsendbreak(), tcdrain(),
  1009. # tcflush(), tcflow(), cfmakeraw(), cfgetospeed(), cfgetispeed(),
  1010. # cfsetispeed(), cfsetospeed(), cfsetspeed()
  1011. #
  1012. # If unsure, say Y.
  1013. config UCLIBC_HAS_EPOLL
  1014. bool "epoll"
  1015. default y
  1016. help
  1017. epoll_create(), epoll_ctl(), epoll_wait() functions.
  1018. config UCLIBC_HAS_XATTR
  1019. bool "Extended Attributes"
  1020. default y
  1021. help
  1022. Extended Attributes support.
  1023. setxattr()
  1024. lsetxattr()
  1025. fsetxattr()
  1026. getxattr()
  1027. lgetxattr()
  1028. fgetxattr()
  1029. listxattr()
  1030. llistxattr()
  1031. flistxattr()
  1032. removexattr()
  1033. lremovexattr()
  1034. fremovexattr()
  1035. Say N unless you need support for extended attributes and the
  1036. filesystems do actually support them.
  1037. config UCLIBC_HAS_PROFILING
  1038. bool "Profiling support"
  1039. default y
  1040. help
  1041. gcc's -finstrument-functions needs these.
  1042. Most people can safely answer N.
  1043. config UCLIBC_HAS_CRYPT_IMPL
  1044. bool "libcrypt support"
  1045. default y
  1046. help
  1047. libcrypt contains crypt(), setkey() and encrypt()
  1048. config UCLIBC_HAS_SHA256_CRYPT_IMPL
  1049. bool "libcrypt SHA256 support"
  1050. depends on UCLIBC_HAS_CRYPT_IMPL
  1051. help
  1052. This adds support for SHA256 password hashing via the crypt() function.
  1053. Say N here if you do not need SHA256 crypt support.
  1054. config UCLIBC_HAS_SHA512_CRYPT_IMPL
  1055. bool "libcrypt SHA512 support"
  1056. depends on UCLIBC_HAS_CRYPT_IMPL
  1057. help
  1058. This adds support for SHA512 password hashing via the crypt() function.
  1059. Say N here if you do not need SHA512 crypt support.
  1060. config UCLIBC_HAS_CRYPT_STUB
  1061. bool "libcrypt stubs"
  1062. default y
  1063. depends on !UCLIBC_HAS_CRYPT_IMPL
  1064. help
  1065. Standards mandate that crypt(3) provides a stub if it is unavailable.
  1066. If you enable this option then stubs for
  1067. crypt(), setkey() and encrypt()
  1068. will be provided in a small libcrypt.
  1069. config UCLIBC_HAS_CRYPT
  1070. def_bool y
  1071. depends on UCLIBC_HAS_CRYPT_IMPL || UCLIBC_HAS_CRYPT_STUB
  1072. endmenu
  1073. menuconfig UCLIBC_HAS_NETWORK_SUPPORT
  1074. bool "Networking Support"
  1075. default y
  1076. help
  1077. Say N here if you do not need network support.
  1078. if UCLIBC_HAS_NETWORK_SUPPORT
  1079. config UCLIBC_HAS_SOCKET
  1080. bool "Socket support"
  1081. default y
  1082. help
  1083. If you want to include support for sockets then answer Y.
  1084. config UCLIBC_HAS_IPV4
  1085. bool "IP version 4 support"
  1086. default y
  1087. select UCLIBC_HAS_SOCKET
  1088. help
  1089. If you want to include support for the Internet Protocol
  1090. (IP version 4) then answer Y.
  1091. Most people will say Y.
  1092. config UCLIBC_HAS_IPV6
  1093. bool "IP version 6 support"
  1094. select UCLIBC_HAS_SOCKET
  1095. help
  1096. If you want to include support for the next version of the Internet
  1097. Protocol (IP version 6) then answer Y.
  1098. Most people should answer N.
  1099. config UCLIBC_HAS_RPC
  1100. bool "Remote Procedure Call (RPC) support"
  1101. # RPC+socket-ipvX doesn't currently work.
  1102. depends on UCLIBC_HAS_IPV4 || UCLIBC_HAS_IPV6
  1103. help
  1104. If you want to include RPC support, enable this. RPC is rarely used
  1105. for anything except for the NFS filesystem. Unless you plan to use
  1106. NFS, you can probably leave this set to N and save some space.
  1107. If you need to use NFS then you should answer Y.
  1108. config UCLIBC_HAS_FULL_RPC
  1109. bool "Full RPC support"
  1110. depends on UCLIBC_HAS_RPC
  1111. default y if !HAVE_SHARED
  1112. help
  1113. Normally we enable just enough RPC support for things like rshd and
  1114. nfs mounts to work. If you find you need the rest of the RPC stuff,
  1115. then enable this option. Most people can safely answer N.
  1116. config UCLIBC_HAS_REENTRANT_RPC
  1117. bool "Reentrant RPC support"
  1118. depends on UCLIBC_HAS_RPC
  1119. default y if !HAVE_SHARED
  1120. help
  1121. Most packages utilize the normal (non-reentrant) RPC functions, but
  1122. some (like exportfs from nfs-utils) need these reentrant versions.
  1123. Most people can safely answer N.
  1124. config UCLIBC_USE_NETLINK
  1125. bool "Use netlink to query interfaces"
  1126. depends on UCLIBC_HAS_SOCKET
  1127. help
  1128. In newer versions of Linux (2.4.17+), support was added for querying
  1129. network device information via netlink rather than the old style
  1130. ioctl's. Most of the time, the older ioctl style is sufficient (and
  1131. it is smaller than netlink), but if you find that not all of your
  1132. devices are being returned by the if_nameindex() function, you will
  1133. have to use the netlink implementation.
  1134. Most people can safely answer N.
  1135. config UCLIBC_SUPPORT_AI_ADDRCONFIG
  1136. bool "Support the AI_ADDRCONFIG flag"
  1137. depends on UCLIBC_USE_NETLINK
  1138. help
  1139. The implementation of AI_ADDRCONFIG is aligned with the glibc
  1140. implementation using netlink to query interfaces to find both
  1141. ipv4 and ipv6 support. This is only needed if an application uses
  1142. the AI_ADDRCONFIG flag.
  1143. Most people can safely answer N.
  1144. config UCLIBC_HAS_BSD_RES_CLOSE
  1145. bool "Support res_close() (bsd-compat)"
  1146. help
  1147. Answer Y if you desperately want to support BSD compatibility in
  1148. the network code.
  1149. Most people will say N.
  1150. config UCLIBC_HAS_COMPAT_RES_STATE
  1151. bool "Use compatible but bloated _res"
  1152. default y
  1153. help
  1154. Answer Y if you build network utilities and they muck with resolver
  1155. internals a lot (_res global structure). uclibc does not use most
  1156. of _res.XXX fields, and with this option OFF they won't even exist.
  1157. Which will make e.g. dig build fail.
  1158. Answering N saves around 400 bytes in bss.
  1159. config UCLIBC_HAS_EXTRA_COMPAT_RES_STATE
  1160. bool "Use extra compatible but extra bloated _res"
  1161. help
  1162. Answer Y if selecting UCLIBC_HAS_COMPAT_RES_STATE is not enough.
  1163. As far as I can say, this should never be needed.
  1164. config UCLIBC_HAS_RESOLVER_SUPPORT
  1165. bool "DNS resolver functions"
  1166. select UCLIBC_HAS_COMPAT_RES_STATE
  1167. depends on UCLIBC_HAS_IPV4 || UCLIBC_HAS_IPV6
  1168. help
  1169. Provide implementations for DNS resolver functions.
  1170. In particular, the following functions will be added to the
  1171. library:
  1172. ns_skiprr, ns_initparse, ns_parserr, ns_msg_getflag,
  1173. res_mkquery, res_init, res_ninit, res_close, res_nclose
  1174. res_query, res_search, res_querydomain,
  1175. dn_expand, dn_comp,
  1176. ns_name_uncompress, ns_name_ntop, ns_name_pton, ns_name_unpack,
  1177. ns_name_pack, ns_name_compress, ns_name_skip, dn_skipname,
  1178. ns_get16, ns_get32, ns_put16, ns_put32
  1179. config UCLIBC_HAS_LIBRESOLV_STUB
  1180. bool "Provide libresolv stub"
  1181. help
  1182. Provide a dummy resolv library.
  1183. config UCLIBC_HAS_LIBNSL_STUB
  1184. bool "Provide libnsl stub"
  1185. help
  1186. Provide a dummy nsl library.
  1187. endif
  1188. menu "String and Stdio Support"
  1189. config UCLIBC_HAS_STRING_GENERIC_OPT
  1190. bool "Use faster (but larger) generic string functions"
  1191. default y
  1192. help
  1193. Answer Y to use the (tweaked) glibc generic string functions.
  1194. In general, they are faster (but 3-5K larger) than the base
  1195. uClibc string functions which are optimized solely for size.
  1196. Many people will answer Y.
  1197. config UCLIBC_HAS_STRING_ARCH_OPT
  1198. bool "Use arch-specific assembly string functions (where available)"
  1199. default y
  1200. help
  1201. Answer Y to use any archtecture-specific assembly language string
  1202. functions available for this target plaform.
  1203. Note that assembly implementations are not available for all string
  1204. functions, so some generic (written in C) string functions may
  1205. still be used.
  1206. These are small and fast, the only reason _not_ to say Y here is
  1207. for debugging purposes.
  1208. config UCLIBC_HAS_STDIO_FUTEXES
  1209. bool "Use futexes for multithreaded I/O locking"
  1210. depends on UCLIBC_HAS_THREADS_NATIVE
  1211. help
  1212. If you want to compile uClibc to use futexes for low-level
  1213. I/O locking, answer Y. Otherwise, answer N.
  1214. config UCLIBC_HAS_CTYPE_TABLES
  1215. bool "Use Table Versions Of 'ctype.h' Functions."
  1216. default y
  1217. help
  1218. Answer Y to use table versions of the 'ctype.h' functions.
  1219. While the non-table versions are often smaller when building
  1220. statically linked apps, they work only in stub locale mode.
  1221. Most people will answer Y.
  1222. config UCLIBC_HAS_CTYPE_SIGNED
  1223. bool "Support Signed Characters In 'ctype.h' Functions."
  1224. depends on UCLIBC_HAS_CTYPE_TABLES
  1225. default y
  1226. help
  1227. Answer Y to enable support for passing signed char values to
  1228. the 'ctype.h' functions. ANSI/ISO C99 and SUSv3 specify that
  1229. these functions are only defined for unsigned char values and
  1230. EOF. However, glibc allows negative signed char values as well
  1231. in order to support 'broken old programs'.
  1232. Most people will answer Y.
  1233. choice
  1234. prompt "ctype argument checking"
  1235. depends on UCLIBC_HAS_CTYPE_TABLES
  1236. default UCLIBC_HAS_CTYPE_UNSAFE
  1237. help
  1238. Please select the invalid arg behavior you want for the 'ctype'
  1239. functions.
  1240. The 'ctype' functions are now implemented using table lookups, with
  1241. the arg being the index. This can result in incorrect memory accesses
  1242. or even segfaults for args outside of the allowed range.
  1243. NOTE: This only affects the 'ctype' _functions_. It does not affect
  1244. the macro implementations.
  1245. config UCLIBC_HAS_CTYPE_UNSAFE
  1246. bool "Do not check -- unsafe"
  1247. config UCLIBC_HAS_CTYPE_CHECKED
  1248. bool "Detect and handle appropriately"
  1249. config UCLIBC_HAS_CTYPE_ENFORCED
  1250. bool "Issue a diagnostic and abort()"
  1251. endchoice
  1252. config UCLIBC_HAS_WCHAR
  1253. bool "Wide Character Support"
  1254. help
  1255. Answer Y to enable wide character support. This will make uClibc
  1256. much larger. It is also currently required for locale support.
  1257. Most people will answer N.
  1258. config UCLIBC_HAS_LOCALE
  1259. bool "Locale Support"
  1260. select UCLIBC_HAS_WCHAR
  1261. select UCLIBC_HAS_CTYPE_TABLES
  1262. help
  1263. uClibc now has full ANSI/ISO C99 locale support (except for
  1264. wcsftime() and collating items in regex). Be aware that enabling
  1265. this option will make uClibc much larger.
  1266. Enabling UCLIBC_HAS_LOCALE with the default set of supported locales
  1267. (169 UTF-8 locales, and 144 locales for other codesets) will enlarge
  1268. uClibc by around 300k. You can reduce this size by building your own
  1269. custom set of locate data (see extra/locale/LOCALES for details).
  1270. uClibc's locale support is still under development. For example,
  1271. codesets using shift states are not currently supported. Support is
  1272. planned in the next iteration of locale support.
  1273. Answer Y to enable locale support. Most people will answer N.
  1274. choice
  1275. prompt "Locale data"
  1276. depends on UCLIBC_HAS_LOCALE
  1277. default UCLIBC_BUILD_ALL_LOCALE
  1278. config UCLIBC_BUILD_ALL_LOCALE
  1279. bool "All locales"
  1280. depends on UCLIBC_HAS_LOCALE
  1281. help
  1282. This builds all the locales that are available on your
  1283. host-box.
  1284. config UCLIBC_BUILD_MINIMAL_LOCALE
  1285. bool "Only selected locales"
  1286. depends on UCLIBC_HAS_LOCALE
  1287. help
  1288. If you do not need all locales that are available on your
  1289. host-box, then set this to 'Y'.
  1290. endchoice
  1291. config UCLIBC_BUILD_MINIMAL_LOCALES
  1292. string "locales to use"
  1293. depends on UCLIBC_BUILD_MINIMAL_LOCALE
  1294. default "en_US"
  1295. help
  1296. Space separated list of locales to use.
  1297. E.g.:
  1298. en_US en_GB de_AT
  1299. default:
  1300. en_US
  1301. config UCLIBC_HAS_XLOCALE
  1302. bool "Extended Locale Support (experimental/incomplete)"
  1303. depends on UCLIBC_HAS_LOCALE
  1304. help
  1305. Answer Y to enable extended locale support similar to that provided
  1306. by glibc. This is primarily intended to support libstd++
  1307. functionality.
  1308. However, it also allows thread-specific locale selection via
  1309. uselocale().
  1310. Most people will answer N.
  1311. config UCLIBC_HAS_HEXADECIMAL_FLOATS
  1312. bool "Support hexadecimal float notation"
  1313. depends on UCLIBC_HAS_CTYPE_TABLES
  1314. depends on UCLIBC_HAS_FLOATS
  1315. help
  1316. Answer Y to enable support for hexadecimal float notation in the
  1317. (wchar and) char string to floating point conversion functions, as
  1318. well as support for the %a and %A conversion specifiers in the
  1319. *printf() and *scanf() functions.
  1320. Most people will answer N.
  1321. config UCLIBC_HAS_GLIBC_DIGIT_GROUPING
  1322. bool "Support glibc's \"'\" flag for allowing locale-specific digit grouping"
  1323. depends on UCLIBC_HAS_LOCALE
  1324. depends on UCLIBC_HAS_FLOATS
  1325. help
  1326. Answer Y to enable support for glibc's \"'\" flag for allowing
  1327. locale-specific digit grouping in base 10 integer conversions and
  1328. appropriate floating point conversions in the *printf() and *scanf()
  1329. functions.
  1330. Most people will answer N.
  1331. config UCLIBC_HAS_SCANF_LENIENT_DIGIT_GROUPING
  1332. bool "Do not require digit grouping when the \"'\" flag is specified"
  1333. depends on UCLIBC_HAS_GLIBC_DIGIT_GROUPING
  1334. default y
  1335. help
  1336. Answer Y to make digit grouping optional when the \"'\" flag is
  1337. specified.
  1338. This is the standard glibc behavior. If the initial string of digits
  1339. exceeds the maximum group number, the input will be treated as a
  1340. normal non-grouped number.
  1341. Most people will answer N.
  1342. config UCLIBC_HAS_GLIBC_CUSTOM_PRINTF
  1343. bool "Support glibc's register_printf_function() (glibc-compat)"
  1344. depends on !USE_OLD_VFPRINTF
  1345. help
  1346. Answer Y to support glibc's register_printf_function() to allow an
  1347. application to add its own printf conversion specifiers.
  1348. parse_printf_format() is also enabled.
  1349. NOTE: Limits the number or registered specifiers to 10.
  1350. NOTE: Requires new conversion specifiers to be ASCII
  1351. characters (0-0x7f). This is to avoid problems with processing
  1352. format strings in locales with different multibyte conversions.
  1353. Most people will answer N.
  1354. config USE_OLD_VFPRINTF
  1355. bool "Use the old vfprintf implementation"
  1356. depends on !UCLIBC_HAS_WCHAR
  1357. help
  1358. Set to true to use the old vfprintf instead of the new. This is
  1359. roughly C89 compliant with some extensions, and is much smaller.
  1360. However, it does not support wide chars, positional args, or glibc
  1361. custom printf specifiers.
  1362. Most people will answer N.
  1363. config UCLIBC_PRINTF_SCANF_POSITIONAL_ARGS
  1364. int "Maximum number of positional args. Either 0 or >= 9."
  1365. depends on !USE_OLD_VFPRINTF
  1366. default 9
  1367. help
  1368. Set the maximum number of positional args supported by the
  1369. printf/scanf functions. The Single Unix Specification Version 3
  1370. requires a minimum value of 9. Setting this to a value lower than
  1371. 9 will disable positional arg support and cause the NL_ARGMAX macro
  1372. in limits.h to be #undef'd.
  1373. WARNING! The workspace to support positional args is currently
  1374. allocated on the stack. You probably don't want to set
  1375. this to too high a value.
  1376. Most people will answer 9.
  1377. choice
  1378. prompt "Stdio buffer size"
  1379. default UCLIBC_HAS_STDIO_BUFSIZ_4096
  1380. help
  1381. Please select a value for BUFSIZ. This will be used by the
  1382. stdio subsystem as the default buffer size for a file, and
  1383. affects fopen(), setvbuf(), etc.
  1384. NOTE: Setting this to 'none' will disable buffering completely.
  1385. However, BUFSIZ will still be defined in stdio.h as 256 because
  1386. many applications use this value.
  1387. config UCLIBC_HAS_STDIO_BUFSIZ_NONE
  1388. bool "none (WARNING - BUFSIZ will be 256 in stdio.h)"
  1389. depends on !UCLIBC_HAS_WCHAR
  1390. config UCLIBC_HAS_STDIO_BUFSIZ_256
  1391. bool "256 (minimum ANSI/ISO C99 value)"
  1392. config UCLIBC_HAS_STDIO_BUFSIZ_512
  1393. bool "512"
  1394. config UCLIBC_HAS_STDIO_BUFSIZ_1024
  1395. bool "1024"
  1396. config UCLIBC_HAS_STDIO_BUFSIZ_2048
  1397. bool "2048"
  1398. config UCLIBC_HAS_STDIO_BUFSIZ_4096
  1399. bool "4096"
  1400. config UCLIBC_HAS_STDIO_BUFSIZ_8192
  1401. bool "8192"
  1402. # If you add more choices, you will need to update uClibc_stdio.h.
  1403. endchoice
  1404. choice
  1405. prompt "Stdio builtin buffer size (uClibc-specific)"
  1406. depends on !UCLIBC_HAS_STDIO_BUFSIZ_NONE
  1407. default UCLIBC_HAS_STDIO_BUILTIN_BUFFER_NONE
  1408. help
  1409. When a FILE is created with fopen(), an attempt is made to allocate
  1410. a BUFSIZ buffer for it. If the allocation fails, fopen() will still
  1411. succeed but the FILE will be unbuffered.
  1412. This option adds a small amount of space to each FILE to act as an
  1413. emergency buffer in the event of a buffer allocation failure.
  1414. Most people will answer None.
  1415. config UCLIBC_HAS_STDIO_BUILTIN_BUFFER_NONE
  1416. bool "None"
  1417. config UCLIBC_HAS_STDIO_BUILTIN_BUFFER_4
  1418. bool "4"
  1419. config UCLIBC_HAS_STDIO_BUILTIN_BUFFER_8
  1420. bool "8"
  1421. # If you add more choices, you will need to update uClibc_stdio.h.
  1422. endchoice
  1423. config UCLIBC_HAS_STDIO_SHUTDOWN_ON_ABORT
  1424. bool "Attempt to shutdown stdio subsystem when abort() is called."
  1425. help
  1426. ANSI/ISO C99 requires abort() to be asyn-signal-safe. So there was
  1427. a behavioral change made in SUSv3. Previously, abort() was required
  1428. to have the affect of fclose() on all open streams. The wording has
  1429. been changed to "may" from "shall".
  1430. Most people will answer N.
  1431. config UCLIBC_HAS_STDIO_GETC_MACRO
  1432. bool "Provide a macro version of getc()"
  1433. depends on !UCLIBC_HAS_STDIO_BUFSIZ_NONE
  1434. default y
  1435. help
  1436. Provide a macro version of getc().
  1437. Most people will answer Y.
  1438. config UCLIBC_HAS_STDIO_PUTC_MACRO
  1439. bool "Provide a macro version of putc()"
  1440. depends on !UCLIBC_HAS_STDIO_BUFSIZ_NONE
  1441. default y
  1442. help
  1443. Provide a macro version of putc().
  1444. Most people will answer Y.
  1445. config UCLIBC_HAS_STDIO_AUTO_RW_TRANSITION
  1446. bool "Support auto-r/w transition"
  1447. default y
  1448. help
  1449. Answer Y to enable the stdio subsystem to automaticly transition
  1450. between reading and writing. This relaxes the ANSI/ISO C99
  1451. requirement:
  1452. When a file is opened with update mode ('+' as the second or third
  1453. character in the list of mode argument values), both input and output
  1454. may be performed on the associated stream. However, output shall not
  1455. be directly followed by input without an intervening call to the
  1456. fflush function or to a file positioning function (fseek, fsetpos,
  1457. or rewind), and input shall not be directly followed by output without
  1458. an intervening call to a file positioning function, unless the input
  1459. operation encounters end­of­file.
  1460. Most people will answer Y.
  1461. config UCLIBC_HAS_FOPEN_LARGEFILE_MODE
  1462. bool "Support an fopen() 'F' flag for large file mode (uClibc-specific)"
  1463. depends on UCLIBC_HAS_LFS
  1464. help
  1465. Answer Y to enable a uClibc-specific extension to allow passing an
  1466. additional 'F' flag in the mode string for fopen() to specify that
  1467. the file should be open()ed with the O_LARGEFILE flag set.
  1468. Most people will answer N.
  1469. config UCLIBC_HAS_FOPEN_EXCLUSIVE_MODE
  1470. bool "Support an fopen() 'x' flag for exclusive mode (glibc-compat)"
  1471. help
  1472. Answer Y to support a glibc extension to allow passing
  1473. additional 'x' flag in the mode string for fopen() to specify that
  1474. the file should be open()ed with the O_EXCL flag set.
  1475. Most people will answer N.
  1476. config UCLIBC_HAS_FOPEN_CLOSEEXEC_MODE
  1477. bool "Support an fopen() 'e' flag for close-on-exec mode (glibc-compat)"
  1478. help
  1479. Answer Y to support a glibc extension to allow passing
  1480. additional 'e' flag in the mode string for fopen() to specify that
  1481. the file should be open()ed with the O_CLOEXEC flag set.
  1482. Most people will answer N.
  1483. config UCLIBC_HAS_GLIBC_CUSTOM_STREAMS
  1484. bool "Support fmemopen(), open_memstream(), and fopencookie() (glibc-compat)"
  1485. help
  1486. Answer Y to support the glibc 'custom stream' extension functions
  1487. fmemopen(), open_memstream(), and fopencookie().
  1488. NOTE: There are some minor differences regarding seeking behavior.
  1489. Most people will answer N.
  1490. config UCLIBC_HAS_PRINTF_M_SPEC
  1491. bool "Support the '%m' specifier in printf format strings (glibc-compat)"
  1492. help
  1493. Answer Y to support a glibc extension to interpret '%m' in printf
  1494. format strings as an instruction to output the error message string
  1495. (as generated by strerror) corresponding to the current value of
  1496. 'errno'.
  1497. Most people will answer N.
  1498. config UCLIBC_HAS_ERRNO_MESSAGES
  1499. bool "Include the errno message text in the library"
  1500. default y
  1501. help
  1502. Answer Y if you want to include the errno message text in the
  1503. library. This adds about 3K to the library, but enables strerror()
  1504. to generate text other than 'Unknown error <number>'.
  1505. Most people will answer Y.
  1506. config UCLIBC_HAS_SYS_ERRLIST
  1507. bool "Support sys_errlist[] (obsolete-compat)"
  1508. depends on UCLIBC_HAS_ERRNO_MESSAGES
  1509. help
  1510. Answer Y if you want to support the obsolete sys_errlist[].
  1511. This adds about 0.5k to the library, except for the mips
  1512. arch where it adds over 4K.
  1513. WARNING! In the future, support for sys_errlist[] may be unavailable
  1514. in at least some configurations. In fact, it may be removed
  1515. altogether.
  1516. Most people will answer N.
  1517. Application writers: use the strerror(3) function.
  1518. config UCLIBC_HAS_SIGNUM_MESSAGES
  1519. bool "Include the signum message text in the library"
  1520. default y
  1521. help
  1522. Answer Y if you want to include the signum message text in the
  1523. library. This adds about 0.5K to the library, but enables strsignal()
  1524. to generate text other than 'Unknown signal <number>'.
  1525. Most people will answer Y.
  1526. config UCLIBC_HAS_SYS_SIGLIST
  1527. bool "Support sys_siglist[] (bsd-compat)"
  1528. depends on UCLIBC_HAS_SIGNUM_MESSAGES
  1529. help
  1530. Answer Y if you want to support sys_siglist[].
  1531. WARNING! In the future, support for sys_siglist[] may be unavailable
  1532. in at least some configurations. In fact, it may be removed
  1533. altogether.
  1534. Most people will answer N.
  1535. config UCLIBC_HAS_GETTEXT_AWARENESS
  1536. bool "Include gettext awareness"
  1537. depends on UCLIBC_HAS_LOCALE && UCLIBC_MJN3_ONLY
  1538. help
  1539. NOTE!!! Not yet integrated with strerror and strsignal. NOTE!!!
  1540. Answer Y if you want to include weak stub gettext support and
  1541. make the *strerror*() and strsignal() functions gettext-aware.
  1542. Currently, to get functional gettext functionality you will need
  1543. to use gnu gettext.
  1544. Most people will answer N.
  1545. config UCLIBC_HAS_GNU_GETOPT
  1546. bool "Support gnu getopt"
  1547. default y
  1548. help
  1549. Answer Y if you want to include full gnu getopt() instead of a
  1550. (much smaller) SUSv3 compatible getopt().
  1551. Note that getopt_long, getopt_long_only as well as getsubopt
  1552. are implemented on top of this choice.
  1553. Most people will answer Y.
  1554. config UCLIBC_HAS_GETOPT_LONG
  1555. bool "Support getopt_long/getopt_long_only (glibc-compat)"
  1556. default y
  1557. help
  1558. Answer Y if you want to include getopt_long[_only()] used by many
  1559. apps.
  1560. Most people will answer Y.
  1561. config UCLIBC_HAS_GNU_GETSUBOPT
  1562. bool "Support getsubopt"
  1563. default y
  1564. help
  1565. Answer Y if you want to include getsubopt().
  1566. Most people will answer Y.
  1567. config UCLIBC_HAS_ARGP
  1568. bool "Support argp (as standalone shared object)"
  1569. default n
  1570. help
  1571. Argp is an interface for parsing unix-style argument vectors. Unlike
  1572. the common getopt interface, it provides many advanced features in
  1573. addition to parsing options, such as automatic output in response to
  1574. `--help' and `--version' options.
  1575. A library can export an argp option parser, which programs can easily
  1576. use in conjunction with their own option parser.
  1577. A new shared object "libuargp" is created. The "libc.so" linker script
  1578. contains the AS_NEEDED entry for getting the libuargp linked automatically.
  1579. Argp support is needed by elfutils libdw.
  1580. Most people can safely answer N.
  1581. endmenu
  1582. menu "Big and Tall"
  1583. config UCLIBC_HAS_REGEX
  1584. bool "Regular Expression Support"
  1585. default y
  1586. help
  1587. POSIX regular expression code is really big -- 53k all by itself.
  1588. If you don't use regular expressions, turn this off and save space.
  1589. Of course, if you only statically link, leave this on, since it will
  1590. only be included in your apps if you use regular expressions.
  1591. config UCLIBC_HAS_REGEX_OLD
  1592. bool "Use the older (stable) regular expression code"
  1593. depends on UCLIBC_HAS_REGEX
  1594. default y
  1595. help
  1596. There are two versions of regex. The older (stable) version has
  1597. been in uClibc for quite a long time but hasn't seen too many
  1598. updates. It also has some known issues when dealing with uncommon
  1599. corner cases and multibyte/unicode strings. However, it is quite
  1600. a bit smaller than the newer version.
  1601. If the older version has worked for you and you don't need unicode
  1602. support, then stick with the old version (and say Y here).
  1603. Otherwise, you should use the new version (and say N here).
  1604. config UCLIBC_HAS_FNMATCH
  1605. bool "fnmatch Support"
  1606. default y
  1607. help
  1608. POSIX fnmatch.
  1609. config UCLIBC_HAS_FNMATCH_OLD
  1610. bool "Use the older (stable) fnmatch code"
  1611. depends on UCLIBC_HAS_FNMATCH
  1612. default y
  1613. help
  1614. There are two versions of fnmatch. The older (stable) version has
  1615. been in uClibc for quite a long time but hasn't seen too many
  1616. updates. It also has some known issues when dealing with uncommon
  1617. corner cases and multibyte/unicode strings. However, it is quite
  1618. a bit smaller than the newer version.
  1619. If the older version has worked for you and you don't need unicode
  1620. support, then stick with the old version (and say Y here).
  1621. Otherwise, you should use the new version (and say N here).
  1622. config UCLIBC_HAS_WORDEXP
  1623. bool "Support the wordexp() interface"
  1624. depends on UCLIBC_HAS_GLOB
  1625. help
  1626. The SuSv3 wordexp() interface performs word expansions per the Shell
  1627. and Utilities volume of IEEE Std 1003.1-2001, Section 2.6. It is
  1628. intended for use by applications that want to implement all of the
  1629. standard Bourne shell expansions on input data.
  1630. This interface is rarely used, and very large. Unless you have a
  1631. pressing need for wordexp(), you should probably answer N.
  1632. config UCLIBC_HAS_NFTW
  1633. bool "Support the nftw() interface"
  1634. help
  1635. The SuSv3 nftw() interface is used to recursively descend
  1636. directory paths while repeatedly calling a function.
  1637. This interface is rarely used, and adds around 4.5k. Unless you have
  1638. a pressing need for nftw(), you should probably answer N.
  1639. config UCLIBC_HAS_FTW
  1640. bool "Support the ftw() interface (SUSv4-obsolete)"
  1641. depends on UCLIBC_SUSV4_LEGACY
  1642. help
  1643. The SuSv3 ftw() interface is used to recursively descend
  1644. directory paths while repeatedly calling a function.
  1645. This interface is rarely used, and adds around 4.5k. Unless you have
  1646. a pressing need for ftw(), you should probably answer N.
  1647. config UCLIBC_HAS_FTS
  1648. bool "Support the fts() interface (bsd-compat)"
  1649. help
  1650. The fts functions are provided for traversing UNIX file hierarchies.
  1651. This interface is currently used by the elfutils and adds
  1652. around 7.5k.
  1653. You should port your application to use the POSIX nftw()
  1654. interface.
  1655. Unless you need to build/use elfutils, you should prolly answer N.
  1656. config UCLIBC_HAS_GLOB
  1657. bool "Support the glob() interface"
  1658. depends on UCLIBC_HAS_FNMATCH
  1659. default y
  1660. help
  1661. The glob interface is somewhat large (weighing in at about 2,5k). It
  1662. is used fairly often, but is an option since people wanting to go for
  1663. absolute minimum size may wish to omit it.
  1664. Most people will answer Y.
  1665. config UCLIBC_HAS_GNU_GLOB
  1666. bool "Support gnu glob() interface"
  1667. depends on UCLIBC_HAS_GLOB
  1668. help
  1669. The gnu glob interface is somewhat larger (weighing in at about 4,2k)
  1670. than it's SuSv3 counterpart (and is out of date). It is an old copy
  1671. from glibc and does not support all the GNU specific options.
  1672. Answer Y if you want to include full gnu glob() instead of the smaller
  1673. SUSv3 compatible glob().
  1674. Most people will answer N.
  1675. endmenu
  1676. menu "Library Installation Options"
  1677. config RUNTIME_PREFIX
  1678. string "uClibc runtime library directory"
  1679. default "/usr/$(TARGET_ARCH)-linux-uclibc/"
  1680. help
  1681. RUNTIME_PREFIX is the directory into which the uClibc runtime
  1682. libraries will be installed. The result will look something
  1683. like the following:
  1684. $(RUNTIME_PREFIX)/
  1685. lib/ <contains all runtime libraries>
  1686. usr/bin/ldd <the ldd utility program>
  1687. sbin/ldconfig <the ldconfig utility program>
  1688. This value is used by the 'make install' Makefile target. Since this
  1689. directory is compiled into the shared library loader, you will need to
  1690. recompile uClibc if you change this value...
  1691. For a typical target system this should be set to "/", such that
  1692. 'make install' will install /lib/libuClibc-<VERSION>.so
  1693. config DEVEL_PREFIX
  1694. string "uClibc development environment directory"
  1695. default "/usr/$(TARGET_ARCH)-linux-uclibc/usr/"
  1696. help
  1697. DEVEL_PREFIX is the directory into which the uClibc development
  1698. environment will be installed. The result will look something
  1699. like the following:
  1700. $(DEVEL_PREFIX)/
  1701. lib/ <contains static libs>
  1702. include/ <Where all the header files go>
  1703. This value is used by the 'make install' Makefile target when
  1704. installing a uClibc development environment.
  1705. For a typical target system this should be set to "/usr", such that
  1706. 'make install' will install /usr/include/<header files>.
  1707. config MULTILIB_DIR
  1708. string "library path component"
  1709. default "lib"
  1710. help
  1711. Path component where libraries reside.
  1712. For a typical target system this should be set to "lib", such that
  1713. 'make install' will install libraries to "/lib" and "/usr/lib"
  1714. respectively
  1715. DEVEL_PREFIX/MULTILIB_DIR
  1716. RUNTIME_PREFIX/MULTILIB_DIR
  1717. Other settings may include "lib32" or "lib64".
  1718. config HARDWIRED_ABSPATH
  1719. bool "Hardwire absolute paths into linker scripts"
  1720. default y
  1721. help
  1722. This prepends absolute paths to the libraries mentioned in linker
  1723. scripts such as libc.so.
  1724. This is a build time optimization. It has no impact on dynamic
  1725. linking at runtime, which doesn't use linker scripts.
  1726. You must disable this to use uClibc with old non-sysroot toolchains,
  1727. such as the prebuilt binary cross compilers at:
  1728. http://uclibc.org/downloads/binaries
  1729. The amount of time saved by this optimization is actually too small to
  1730. measure. The linker just had to search the library path to find the
  1731. linker script, so the dentries are cache hot if it has to search the
  1732. same path again. But it's what glibc does, so we do it too.
  1733. endmenu
  1734. menu "Security options"
  1735. config UCLIBC_BUILD_PIE
  1736. bool "Build utilities as ET_DYN/PIE executables"
  1737. depends on HAVE_SHARED
  1738. depends on TARGET_arm || TARGET_frv || TARGET_i386 || TARGET_mips || TARGET_powerpc
  1739. select FORCE_SHAREABLE_TEXT_SEGMENTS
  1740. help
  1741. If you answer Y here, ldd and iconv are built as ET_DYN/PIE
  1742. executables.
  1743. It requires gcc-3.4 and binutils-2.15 (for arm 2.16) or later.
  1744. More about ET_DYN/PIE binaries on <http://pax.grsecurity.net/> .
  1745. WARNING: This option also enables FORCE_SHAREABLE_TEXT_SEGMENTS, so
  1746. all libraries have to be built with -fPIC or -fpic, and all
  1747. assembler functions must be written as position independent
  1748. code (PIC).
  1749. config UCLIBC_HAS_ARC4RANDOM
  1750. bool "Include the arc4random() function"
  1751. help
  1752. Answer Y to support the OpenBSD-like arc4random() function. This
  1753. function picks a random number between 0 and N, and will always return
  1754. something even if the random driver is dead. If urandom fails then
  1755. gettimeofday(2) will be used as the random seed. This function is
  1756. designed to be more dependable than invoking /dev/urandom directly.
  1757. OpenSSL and OpenNTPD currently support this function.
  1758. Most people will answer N.
  1759. config ARC4RANDOM_USES_NODEV
  1760. bool "Do not use /dev/urandom with arc4random()"
  1761. depends on UCLIBC_HAS_ARC4RANDOM
  1762. help
  1763. Answer Y to use gettimeofday(2) and getpid(2) exclusively for
  1764. arc4random(). This is not a bad idea for a diskless system, but
  1765. it uses a lot of syscalls to stir each array element.
  1766. Most people will answer N.
  1767. config HAVE_NO_SSP
  1768. bool
  1769. config UCLIBC_HAS_SSP
  1770. bool "Support for GCC stack smashing protector"
  1771. depends on !HAVE_NO_SSP
  1772. help
  1773. Add code to support GCC's -fstack-protector[-all] option to uClibc.
  1774. This requires GCC 4.1 or newer. GCC does not have to provide libssp,
  1775. the needed functions are added to ldso/libc instead.
  1776. GCC's stack protector is a reimplementation of IBM's propolice.
  1777. See http://www.trl.ibm.com/projects/security/ssp/ and
  1778. http://www.linuxfromscratch.org/hints/downloads/files/ssp.txt
  1779. for details.
  1780. Note that NOEXECSTACK on a kernel with address space randomization
  1781. is generally sufficient to prevent most buffer overflow exploits
  1782. without increasing code size. This option essentially adds debugging
  1783. code to catch them.
  1784. Most people will answer N.
  1785. config UCLIBC_HAS_SSP_COMPAT
  1786. bool "Support for gcc-3.x propolice smashing stack protector"
  1787. depends on UCLIBC_HAS_SSP
  1788. help
  1789. Add gcc-3.x propolice smashing stack protector to the library.
  1790. This requires a patched version of GCC, supporting the
  1791. -fstack-protector[-all] options, with the __guard and
  1792. __stack_smash_handler functions removed from libgcc.
  1793. These functions are added to ldso/libc instead.
  1794. More information at:
  1795. <http://www.research.ibm.com/trl/projects/security/ssp/>
  1796. Most people will answer N.
  1797. config SSP_QUICK_CANARY
  1798. bool "Use simple guard values without accessing /dev/urandom"
  1799. depends on UCLIBC_HAS_SSP
  1800. help
  1801. Use gettimeofday(2) to define the __guard without accessing
  1802. /dev/urandom.
  1803. WARNING: This makes smashing stack protector vulnerable to timing
  1804. attacks.
  1805. Most people will answer N.
  1806. choice
  1807. prompt "Propolice protection blocking signal"
  1808. depends on UCLIBC_HAS_SSP
  1809. depends on DODEBUG
  1810. default PROPOLICE_BLOCK_SEGV
  1811. help
  1812. "abort" use SIGABRT to block offending programs.
  1813. This is the default implementation.
  1814. "segfault" use SIGSEGV to block offending programs.
  1815. Use this for debugging.
  1816. If unsure, answer "abort".
  1817. config PROPOLICE_BLOCK_ABRT
  1818. bool "abort"
  1819. config PROPOLICE_BLOCK_SEGV
  1820. bool "segfault"
  1821. endchoice
  1822. config UCLIBC_BUILD_SSP
  1823. bool "Build uClibc with -fstack-protector"
  1824. depends on UCLIBC_HAS_SSP
  1825. help
  1826. Build all uClibc libraries and executables with -fstack-protector,
  1827. adding extra stack overflow checking to most uClibc functions.
  1828. config UCLIBC_BUILD_RELRO
  1829. bool "Build uClibc with linker option -z RELRO"
  1830. depends on HAVE_SHARED
  1831. default y
  1832. help
  1833. Build all libraries and executables with "ld -z relro".
  1834. This tells the linker to mark chunks of an executable or shared
  1835. library read-only after applying dynamic relocations. (This comes
  1836. up when a global const variable is initialized to the address of a
  1837. function or the value of another global variable.)
  1838. This is a fairly obscure option the ld man page doesn't even bother
  1839. to document properly. It's a security paranoia issue that's more
  1840. likely to consume memory (by allocating an extra page) rather than
  1841. save it.
  1842. This is explained in more depth at
  1843. http://www.airs.com/blog/archives/189
  1844. Nobody is likely to care whether you say Y or N here.
  1845. config UCLIBC_BUILD_NOW
  1846. bool "Build uClibc with linker option -z NOW"
  1847. depends on HAVE_SHARED
  1848. help
  1849. Build all libraries and executables with "ld -z now".
  1850. This tells the linker to resolve all symbols when the library is
  1851. first loaded, rather than when each function is first called. This
  1852. increases start-up latency by a few microseconds and may do
  1853. unnecessary work (resolving symbols that are never used), but the
  1854. realtime people like it for making microbenchmark timings slightly
  1855. more predictable and in some cases it can be slightly faster due to
  1856. CPU cache behavior (not having to fault the linker back in to do
  1857. lazy symbol resolution).
  1858. Most people can't tell the difference between selecting Y or N here.
  1859. config UCLIBC_BUILD_NOEXECSTACK
  1860. bool "Build uClibc with noexecstack marking"
  1861. default y
  1862. help
  1863. Mark all assembler files as noexecstack, which will mark uClibc
  1864. as not requiring an executable stack. (This doesn't prevent other
  1865. files you link against from claiming to need an executable stack, it
  1866. just won't cause uClibc to request it unnecessarily.)
  1867. This is a security thing to make buffer overflows harder to exploit.
  1868. By itself, it's kind of useless, as Linus Torvalds explained in 1998:
  1869. http://old.lwn.net/1998/0806/a/linus-noexec.html
  1870. It only actually provides any security when combined with address
  1871. space randomization, explained here: http://lwn.net/Articles/121845/
  1872. Address space randomization is on by default in current linux
  1873. kernels (although it can be disabled using the option
  1874. CONFIG_COMPAT_BRK).
  1875. You should probably say Y.
  1876. endmenu
  1877. menu "Development/debugging options"
  1878. config CROSS_COMPILER_PREFIX
  1879. string "Cross-compiling toolchain prefix"
  1880. default ""
  1881. help
  1882. The prefix used to execute your cross-compiling toolchain. For
  1883. example, if you run 'arm-linux-uclibc-gcc' to compile something,
  1884. then enter 'arm-linux-uclibc-' here.
  1885. config UCLIBC_EXTRA_CFLAGS
  1886. string "Extra CFLAGS"
  1887. default ""
  1888. help
  1889. Add any additional CFLAGS to be used to build uClibc.
  1890. config DODEBUG
  1891. bool "Enable debugging symbols"
  1892. select EXTRA_WARNINGS
  1893. help
  1894. Say Y here if you wish to compile uClibc with debugging symbols.
  1895. This will allow you to use a debugger to examine uClibc internals
  1896. while applications are running. This increases the size of the
  1897. library considerably and should only be used when doing development.
  1898. If you are doing development and want to debug uClibc, answer Y.
  1899. Otherwise, answer N.
  1900. config DODEBUG_PT
  1901. bool "Build pthread with debugging output"
  1902. depends on UCLIBC_HAS_THREADS && LINUXTHREADS_OLD
  1903. help
  1904. Enable debug output in libpthread. This is only useful when doing
  1905. development in libpthread itself.
  1906. Otherwise, answer N.
  1907. config DOSTRIP
  1908. bool "Strip libraries and executables"
  1909. default y
  1910. depends on !DODEBUG
  1911. help
  1912. Say Y here if you do wish to strip all uClibc libraries and
  1913. executables. No stripping increases the size of the binaries
  1914. considerably, but makes it possible to debug uClibc libraries.
  1915. Most people will answer Y.
  1916. config DOASSERTS
  1917. bool "Build with run-time assertion testing"
  1918. help
  1919. Say Y here to include runtime assertion tests.
  1920. This enables runtime assertion testing in some code, which can
  1921. increase the size of the library and incur runtime overhead.
  1922. If you say N, then this testing will be disabled.
  1923. config SUPPORT_LD_DEBUG
  1924. bool "Build the shared library loader with debugging support"
  1925. depends on HAVE_SHARED
  1926. help
  1927. Answer Y here to enable all the extra code needed to debug the uClibc
  1928. native shared library loader. The level of debugging noise that is
  1929. generated depends on the LD_DEBUG environment variable... Just set
  1930. LD_DEBUG to something like: 'LD_DEBUG=token1,token2,.. prog' to
  1931. debug your application. Diagnostic messages will then be printed to
  1932. the stderr.
  1933. For now these debugging tokens are available:
  1934. detail provide more information for some options
  1935. move display copy processing
  1936. symbols display symbol table processing
  1937. reloc display relocation processing; detail shows the
  1938. relocation patch
  1939. nofixups never fixes up jump relocations
  1940. bindings displays the resolve processing (function calls);
  1941. detail shows the relocation patch
  1942. all Enable everything!
  1943. The additional environment variable:
  1944. LD_DEBUG_OUTPUT=file
  1945. redirects the diagnostics to an output file created using
  1946. the specified name and the process id as a suffix.
  1947. An excellent start is simply:
  1948. $ LD_DEBUG=binding,move,symbols,reloc,detail ./appname
  1949. or to log everything to a file named 'logfile', try this
  1950. $ LD_DEBUG=all LD_DEBUG_OUTPUT=logfile ./appname
  1951. If you are doing development and want to debug uClibc's shared library
  1952. loader, answer Y. Mere mortals answer N.
  1953. config SUPPORT_LD_DEBUG_EARLY
  1954. bool "Build the shared library loader with early debugging support"
  1955. depends on HAVE_SHARED
  1956. help
  1957. Answer Y here to if you find the uClibc shared library loader is
  1958. crashing or otherwise not working very early on. This is typical
  1959. only when starting a new port when you haven't figured out how to
  1960. properly get the values for argc, argv, environ, etc. This method
  1961. allows a degree of visibility into the very early shared library
  1962. loader initialization process. If you are doing development and want
  1963. to debug the uClibc shared library loader early initialization,
  1964. answer Y. Mere mortals answer N.
  1965. config UCLIBC_MALLOC_DEBUGGING
  1966. bool "Build malloc with debugging support"
  1967. depends on MALLOC || MALLOC_STANDARD
  1968. select DOASSERTS
  1969. help
  1970. Answer Y here to compile extra debugging support code into malloc.
  1971. Malloc debugging output may then be enabled at runtime using the
  1972. MALLOC_DEBUG environment variable.
  1973. The value of MALLOC_DEBUG should be an integer, which is interpreted
  1974. as a bitmask with the following bits:
  1975. 1 - do extra consistency checking
  1976. 2 - output messages for malloc/free calls and OS
  1977. allocation calls
  1978. 4 - output messages for the `MMB' layer
  1979. 8 - output messages for internal malloc heap manipulation
  1980. calls
  1981. Because this increases the size of malloc appreciably (due to strings
  1982. etc), you should say N unless you need to debug a malloc problem.
  1983. config UCLIBC_HAS_BACKTRACE
  1984. bool "Add support for application self-debugging"
  1985. depends on HAVE_SHARED
  1986. help
  1987. Answer Y here to compile support for application self-debugging, by adding
  1988. a new shared object "libubacktrace.so" that provides the following new
  1989. functions:
  1990. backtrace, backtrace_symbols, backtrace_symbols_fd
  1991. The backtrace functionality is currently supported on SH platform, and it
  1992. based on dwarf2 informations to properly work, so any application that
  1993. want to use backtrace needs to be built with -fexceptions flag.
  1994. The symbol names may be unavailable without the use of special linker
  1995. options. For systems using the GNU linker, it is necessary to use the
  1996. -rdynamic linker option too. Note that names of "static" functions are not
  1997. exposed, and won't be available in the backtrace.
  1998. config WARNINGS
  1999. string "Compiler Warnings"
  2000. default "-Wall"
  2001. help
  2002. Set this to the set of compiler warnings you wish to see while compiling.
  2003. config EXTRA_WARNINGS
  2004. bool "Enable extra annoying warnings"
  2005. help
  2006. If you wish to build with extra warnings enabled, say Y here.
  2007. config DOMULTI
  2008. bool "Compile all sources at once into an object"
  2009. help
  2010. Set this to compile all sources at once into an object (IMA).
  2011. This mode of compilation uses alot of memory but may produce
  2012. smaller binaries.
  2013. Note that you need a very recent GCC for this to work, like
  2014. gcc >= 4.3 plus eventually some patches.
  2015. If unsure, keep the default of N.
  2016. endmenu