Config.in 72 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_aarch64 if DESIRED_TARGET_ARCH = "aarch64"
  15. default TARGET_alpha if DESIRED_TARGET_ARCH = "alpha"
  16. default TARGET_arc if DESIRED_TARGET_ARCH = "arc"
  17. default TARGET_arm if DESIRED_TARGET_ARCH = "arm"
  18. default TARGET_avr32 if DESIRED_TARGET_ARCH = "avr32"
  19. default TARGET_bfin if DESIRED_TARGET_ARCH = "bfin"
  20. default TARGET_cris if DESIRED_TARGET_ARCH = "cris"
  21. default TARGET_csky if DESIRED_TARGET_ARCH = "csky"
  22. default TARGET_frv if DESIRED_TARGET_ARCH = "frv"
  23. default TARGET_h8300 if DESIRED_TARGET_ARCH = "h8300"
  24. default TARGET_hppa if DESIRED_TARGET_ARCH = "hppa"
  25. default TARGET_i386 if DESIRED_TARGET_ARCH = "i386"
  26. default TARGET_ia64 if DESIRED_TARGET_ARCH = "ia64"
  27. default TARGET_kvx if DESIRED_TARGET_ARCH = "kvx"
  28. default TARGET_lm32 if DESIRED_TARGET_ARCH = "lm32"
  29. default TARGET_m68k if DESIRED_TARGET_ARCH = "m68k"
  30. default TARGET_metag if DESIRED_TARGET_ARCH = "metag"
  31. default TARGET_microblaze if DESIRED_TARGET_ARCH = "microblaze"
  32. default TARGET_mips if DESIRED_TARGET_ARCH = "mips"
  33. default TARGET_nds32 if DESIRED_TARGET_ARCH = "nds32"
  34. default TARGET_nios2 if DESIRED_TARGET_ARCH = "nios2"
  35. default TARGET_or1k if DESIRED_TARGET_ARCH = "or1k"
  36. default TARGET_powerpc if DESIRED_TARGET_ARCH = "powerpc"
  37. default TARGET_riscv64 if DESIRED_TARGET_ARCH = "riscv64"
  38. default TARGET_sh if DESIRED_TARGET_ARCH = "sh"
  39. default TARGET_sparc if DESIRED_TARGET_ARCH = "sparc"
  40. default TARGET_sparc64 if DESIRED_TARGET_ARCH = "sparc64"
  41. default TARGET_tile if DESIRED_TARGET_ARCH = "tile"
  42. default TARGET_x86_64 if DESIRED_TARGET_ARCH = "x86_64"
  43. default TARGET_xtensa if DESIRED_TARGET_ARCH = "xtensa"
  44. help
  45. The architecture of your target.
  46. config TARGET_aarch64
  47. bool "aarch64"
  48. config TARGET_alpha
  49. bool "alpha"
  50. config TARGET_arc
  51. bool "arc"
  52. config TARGET_arm
  53. bool "arm"
  54. config TARGET_avr32
  55. bool "avr32"
  56. config TARGET_bfin
  57. bool "bfin"
  58. # someone could sync this tree:
  59. # http://linux-c6x.org/git/?p=uClibc.git;a=summary
  60. config TARGET_c6x
  61. bool "c6x"
  62. config TARGET_cris
  63. bool "cris"
  64. config TARGET_csky
  65. bool "csky"
  66. config TARGET_frv
  67. bool "frv"
  68. config TARGET_h8300
  69. bool "h8300"
  70. config TARGET_hppa
  71. bool "hppa"
  72. config TARGET_i386
  73. bool "i386"
  74. config TARGET_ia64
  75. bool "ia64"
  76. config TARGET_kvx
  77. bool "kvx"
  78. config TARGET_lm32
  79. bool "lm32"
  80. config TARGET_m68k
  81. bool "m68k"
  82. config TARGET_metag
  83. bool "metag"
  84. config TARGET_microblaze
  85. bool "microblaze"
  86. config TARGET_mips
  87. bool "mips"
  88. config TARGET_nds32
  89. bool "nds32"
  90. config TARGET_nios2
  91. bool "nios2"
  92. config TARGET_or1k
  93. bool "or1k"
  94. config TARGET_powerpc
  95. bool "powerpc"
  96. config TARGET_riscv64
  97. bool "riscv64"
  98. config TARGET_sh
  99. bool "superh"
  100. config TARGET_sparc
  101. bool "sparc"
  102. config TARGET_sparc64
  103. bool "sparc64"
  104. config TARGET_tile
  105. bool "tile"
  106. config TARGET_x86_64
  107. bool "x86_64"
  108. config TARGET_xtensa
  109. bool "xtensa"
  110. endchoice
  111. config TARGET_LDSO_NAME
  112. string
  113. default "ld64-uClibc" if TARGET_ia64
  114. default "ld64-uClibc" if TARGET_powerpc64
  115. default "ld64-uClibc" if TARGET_sparc64
  116. default "ld64-uClibc" if TARGET_x86_64
  117. default "ld64-uClibc" if TARGET_kvx
  118. default "ld64-uClibc" if CONFIG_MIPS_N64_ABI
  119. default "ld-uClibc"
  120. config TARGET_ARCH_BITS
  121. int
  122. default 64 if TARGET_aarch64
  123. default 64 if TARGET_ia64
  124. default 64 if TARGET_powerpc64
  125. default 64 if TARGET_sparc64
  126. default 64 if TARGET_x86_64
  127. default 64 if TARGET_kvx
  128. default 64 if CONFIG_MIPS_N64_ABI
  129. default 32
  130. menu "Target Architecture Features and Options"
  131. if TARGET_aarch64
  132. source "extra/Configs/Config.aarch64"
  133. endif
  134. if TARGET_alpha
  135. source "extra/Configs/Config.alpha"
  136. endif
  137. if TARGET_arm
  138. source "extra/Configs/Config.arm"
  139. endif
  140. if TARGET_avr32
  141. source "extra/Configs/Config.avr32"
  142. endif
  143. if TARGET_bfin
  144. source "extra/Configs/Config.bfin"
  145. endif
  146. if TARGET_cris
  147. source "extra/Configs/Config.cris"
  148. endif
  149. if TARGET_csky
  150. source "extra/Configs/Config.csky"
  151. endif
  152. if TARGET_frv
  153. source "extra/Configs/Config.frv"
  154. endif
  155. if TARGET_h8300
  156. source "extra/Configs/Config.h8300"
  157. endif
  158. if TARGET_hppa
  159. source "extra/Configs/Config.hppa"
  160. endif
  161. if TARGET_i386
  162. source "extra/Configs/Config.i386"
  163. endif
  164. if TARGET_ia64
  165. source "extra/Configs/Config.ia64"
  166. endif
  167. if TARGET_kvx
  168. source "extra/Configs/Config.kvx"
  169. endif
  170. if TARGET_lm32
  171. source "extra/Configs/Config.lm32"
  172. endif
  173. if TARGET_m68k
  174. source "extra/Configs/Config.m68k"
  175. endif
  176. if TARGET_metag
  177. source "extra/Configs/Config.metag"
  178. endif
  179. if TARGET_nds32
  180. source "extra/Configs/Config.nds32"
  181. endif
  182. if TARGET_nios2
  183. source "extra/Configs/Config.nios2"
  184. endif
  185. if TARGET_microblaze
  186. source "extra/Configs/Config.microblaze"
  187. endif
  188. if TARGET_mips
  189. source "extra/Configs/Config.mips"
  190. endif
  191. if TARGET_or1k
  192. source "extra/Configs/Config.or1k"
  193. endif
  194. if TARGET_powerpc
  195. source "extra/Configs/Config.powerpc"
  196. endif
  197. if TARGET_riscv64
  198. source "extra/Configs/Config.riscv64"
  199. endif
  200. if TARGET_sh
  201. source "extra/Configs/Config.sh"
  202. endif
  203. if TARGET_sparc
  204. source "extra/Configs/Config.sparc"
  205. endif
  206. if TARGET_sparc64
  207. source "extra/Configs/Config.sparc64"
  208. endif
  209. if TARGET_tile
  210. source "extra/Configs/Config.tile"
  211. endif
  212. if TARGET_x86_64
  213. source "extra/Configs/Config.x86_64"
  214. endif
  215. if TARGET_xtensa
  216. source "extra/Configs/Config.xtensa"
  217. endif
  218. if TARGET_c6x
  219. source "extra/Configs/Config.c6x"
  220. endif
  221. if TARGET_arc
  222. source "extra/Configs/Config.arc"
  223. endif
  224. config TARGET_SUBARCH
  225. string
  226. default "e500" if CONFIG_E500
  227. default "classic" if CONFIG_CLASSIC
  228. default "sh4" if CONFIG_SH4
  229. default "sh4" if CONFIG_SH4A
  230. default "" if CONFIG_386
  231. default "i486" if CONFIG_486
  232. default "i586" if CONFIG_586
  233. default "i686" if CONFIG_686
  234. default ""
  235. source "extra/Configs/Config.in.arch"
  236. endmenu
  237. menu "General Library Settings"
  238. config HAVE_NO_PIC
  239. bool
  240. config DOPIC
  241. bool "Generate only Position Independent Code (PIC)"
  242. default y
  243. depends on !HAVE_NO_PIC
  244. help
  245. If you wish to build all of uClibc as PIC objects, then answer Y here.
  246. If you are unsure, then you should answer N.
  247. config STATIC_PIE
  248. bool "Add support for Static Position Independent Executables (PIE)"
  249. default n
  250. depends on DOPIC && !UCLIBC_FORMAT_FDPIC_ELF && \
  251. (TARGET_arm || TARGET_i386 || TARGET_x86_64 || TARGET_aarch64 || \
  252. TARGET_mips || TARGET_xtensa)
  253. config ARCH_HAS_NO_SHARED
  254. bool
  255. config ARCH_HAS_NO_LDSO
  256. bool
  257. select ARCH_HAS_NO_SHARED
  258. config ARCH_HAS_UCONTEXT
  259. bool
  260. config HAVE_SHARED
  261. bool "Enable shared libraries"
  262. depends on !ARCH_HAS_NO_SHARED
  263. default y
  264. help
  265. If you wish to build uClibc with support for shared libraries then
  266. answer Y here. If you only want to build uClibc as a static library,
  267. then answer N.
  268. config FORCE_SHAREABLE_TEXT_SEGMENTS
  269. bool "Only load shared libraries which can share their text segment"
  270. depends on HAVE_SHARED
  271. select DOPIC
  272. help
  273. If you answer Y here, the uClibc native shared library loader will
  274. only load shared libraries, which do not need to modify any
  275. non-writable segments. These libraries haven't set the DT_TEXTREL
  276. tag in the dynamic section (==> objdump).
  277. All your libraries must be compiled with -fPIC or -fpic, and all
  278. assembler function must be written as position independent code (PIC).
  279. Enabling this option will make uClibc's shared library loader a
  280. little bit smaller and guarantee that no memory will be wasted by
  281. badly coded shared libraries.
  282. config LDSO_LDD_SUPPORT
  283. bool "Native 'ldd' support"
  284. depends on HAVE_SHARED
  285. default y
  286. help
  287. Enable all the code needed to support traditional ldd,
  288. which executes the shared library loader to resolve all dependencies
  289. and then provide a list of shared libraries that are required for an
  290. application to function. Disabling this option will make uClibc's
  291. shared library loader a little bit smaller.
  292. Most people will answer Y.
  293. config LDSO_CACHE_SUPPORT
  294. bool "Enable library loader cache (ld.so.conf)"
  295. depends on HAVE_SHARED
  296. default y
  297. help
  298. Enable this to make use of /etc/ld.so.conf, the shared library loader
  299. cache configuration file to support for non-standard library paths.
  300. After updating this file, it is necessary to run 'ldconfig' to update
  301. the /etc/ld.so.cache shared library loader cache file.
  302. config LDSO_PRELOAD_ENV_SUPPORT
  303. bool "Enable library loader LD_PRELOAD environment"
  304. depends on HAVE_SHARED
  305. default y
  306. help
  307. Enable this to make use of LD_PRELOAD environment variable.
  308. A whitespace-separated list of additional, user-specified, ELF shared
  309. libraries to be loaded before all others. This can be used to
  310. selectively override functions in other shared libraries. For
  311. set-user-ID/set-group-ID ELF binaries, only libraries in the standard
  312. search directories that are also set-user-ID will be loaded.
  313. config LDSO_PRELOAD_FILE_SUPPORT
  314. bool "Enable library loader preload file (ld.so.preload)"
  315. depends on HAVE_SHARED
  316. help
  317. Enable this to make use of /etc/ld.so.preload. This file contains a
  318. whitespace separated list of shared libraries to be loaded before
  319. the program.
  320. config LDSO_BASE_FILENAME
  321. string "Shared library loader naming prefix"
  322. depends on HAVE_SHARED && (LDSO_CACHE_SUPPORT || LDSO_PRELOAD_FILE_SUPPORT)
  323. default "ld.so"
  324. help
  325. If you wish to support both uClibc and glibc on the same system, it
  326. is necessary to set this to something other than "ld.so" to avoid
  327. conflicts with glibc, which also uses "ld.so". This prevents both
  328. libraries from using the same /etc/ld.so.* files. If you wish to
  329. support both uClibc and glibc on the same system then you should set
  330. this to "ld-uClibc.so".
  331. Most people will leave this set to the default of "ld.so".
  332. WARNING: Changing the default prefix could cause problems with
  333. binutils' ld !
  334. config LDSO_STANDALONE_SUPPORT
  335. bool "Dynamic linker stand-alone mode support"
  336. depends on HAVE_SHARED
  337. help
  338. The dynamic linker can be run either indirectly through running some
  339. dynamically linked program or library (in which case no command line
  340. options to the dynamic linker can be passed and, in the ELF case, the
  341. dynamic linker which is stored in the .interp section of the program
  342. is executed) or directly by running:
  343. /lib/ld-uClibc.so.* [OPTIONS] [PROGRAM [ARGUMENTS]]
  344. Stand-alone execution is a prerequisite for adding prelink
  345. capabilities to uClibc dynamic linker, as well useful for testing an
  346. updated version of the dynamic linker without breaking the system.
  347. config LDSO_PRELINK_SUPPORT
  348. bool "Dynamic linker prelink support"
  349. depends on HAVE_SHARED
  350. select LDSO_STANDALONE_SUPPORT
  351. help
  352. The dynamic linker can be used in stand-alone mode by the prelink tool
  353. for prelinking ELF shared libraries and binaries to speed up startup
  354. time. It also is able to load and handle prelinked libraries and
  355. binaries at runtime.
  356. config UCLIBC_STATIC_LDCONFIG
  357. bool "Link ldconfig statically"
  358. depends on HAVE_SHARED
  359. default y
  360. help
  361. Enable this option to statically link the ldconfig binary.
  362. Making ldconfig static can be beneficial if you have a library
  363. problem and need to use ldconfig to recover. Sometimes it is
  364. preferable to instead keep the size of the system down, in which
  365. case you should disable this option.
  366. config LDSO_RUNPATH
  367. bool "Enable ELF RUNPATH tag support"
  368. depends on HAVE_SHARED
  369. default y if LDSO_CACHE_SUPPORT
  370. help
  371. ELF's may have dynamic RPATH/RUNPATH tags. These tags list paths
  372. which extend the library search paths. They are really only useful
  373. if a package installs libraries in non standard locations and
  374. ld.so.conf support is disabled.
  375. Usage of RUNPATH tags is not too common, so disabling this feature
  376. should be safe for most people.
  377. config LDSO_RUNPATH_OF_EXECUTABLE
  378. bool "Use executables RUNPATH/RPATH when searching for libraries."
  379. depends on LDSO_RUNPATH
  380. default n
  381. help
  382. Use the executables RUNPATH/RPATH to find to find libraries even
  383. though this behavour is not standard. Setting this option causes
  384. the uclibc dynamic linker behavour to match the glibc dynamic linker.
  385. config LDSO_SAFE_RUNPATH
  386. bool "Allow only RUNPATH beginning with /"
  387. depends on LDSO_RUNPATH
  388. default y
  389. help
  390. Allow only absolute path in RPATH/RUNPATH.
  391. config LDSO_SEARCH_INTERP_PATH
  392. bool "Add ldso path to lib search path"
  393. depends on HAVE_SHARED
  394. default y
  395. help
  396. The ldso is told where it is being executed from and can use that
  397. path to find related core libraries. This is useful by default,
  398. but can be annoying in a mixed development environment.
  399. i.e. if the ldso is run from /foo/boo/ldso.so, it will start its
  400. library search with /foo/boo/
  401. If unsure, simply say Y here.
  402. config LDSO_LD_LIBRARY_PATH
  403. bool "Add LD_LIBRARY_PATH to lib search path"
  404. depends on HAVE_SHARED
  405. default y
  406. help
  407. On hardened system it could be useful to disable the use of
  408. LD_LIBRARY_PATH environment variable (a colon-separated list of
  409. directories in which to search for ELF libraries at execution-time).
  410. If unsure, simply say Y here.
  411. config UCLIBC_CTOR_DTOR
  412. bool
  413. default y if !TARGET_riscv64
  414. help
  415. If you wish to build uClibc with support for global constructor
  416. (ctor) and global destructor (dtor) support, then answer Y here.
  417. When ctor/dtor support is enabled, binaries linked with uClibc must
  418. also be linked with crtbegin.o and crtend.o which are provided by gcc
  419. (the "*startfile:" and "*endfile:" settings in your gcc specs file
  420. may need to be adjusted to include these files). This support will
  421. also add a small amount of additional size to each binary compiled vs
  422. uClibc. If you will be using uClibc with C++, or if you need the gcc
  423. __attribute__((constructor)) and __attribute__((destructor)) to work,
  424. then you definitely want to answer Y here. If you don't need ctors
  425. or dtors and want your binaries to be as small as possible, then
  426. answer N.
  427. config LDSO_GNU_HASH_SUPPORT
  428. bool "Enable GNU hash style support"
  429. depends on HAVE_SHARED && !TARGET_mips
  430. help
  431. Newest binutils support a new hash style named GNU-hash. The dynamic
  432. linker will use the new GNU-hash section (.gnu.hash) for symbol lookup
  433. if present into the ELF binaries, otherwise it will use the old SysV
  434. hash style (.hash). This ensures that it is completely backward
  435. compatible.
  436. Further, being the hash table implementation self-contained into each
  437. executable and shared libraries, objects with mixed hash style can
  438. peacefully coexist in the same process.
  439. If you want to use this new feature, answer Y
  440. choice
  441. prompt "Thread support"
  442. default HAS_NO_THREADS
  443. help
  444. If you want to compile uClibc with pthread support, then answer Y.
  445. This will increase the size of uClibc by adding a bunch of locking
  446. to critical data structures, and adding extra code to ensure that
  447. functions are properly reentrant.
  448. config HAS_NO_THREADS
  449. bool "none"
  450. help
  451. Disable thread support.
  452. config UCLIBC_HAS_LINUXTHREADS
  453. bool "Linuxthreads"
  454. # linuxthreads need nanosleep()
  455. select UCLIBC_HAS_REALTIME
  456. depends on !TARGET_aarch64 && \
  457. !TARGET_riscv64 && \
  458. !TARGET_metag
  459. help
  460. If you want to compile uClibc with Linuxthreads support, then answer Y.
  461. config UCLIBC_HAS_THREADS_NATIVE
  462. bool "Native POSIX Threading (NPTL)"
  463. select UCLIBC_HAS_TLS
  464. select UCLIBC_HAS_STDIO_FUTEXES
  465. select UCLIBC_HAS_REALTIME
  466. # i386 has no lowlevellock support (yet) as opposed to i486 onward
  467. depends on !CONFIG_386 && \
  468. !TARGET_alpha && \
  469. !TARGET_avr32 && \
  470. !TARGET_bfin && \
  471. !TARGET_c6x && \
  472. !TARGET_cris && \
  473. !TARGET_frv && \
  474. !TARGET_h8300 && \
  475. !TARGET_hppa && \
  476. !TARGET_ia64 && \
  477. (ARCH_USE_MMU || TARGET_arm)
  478. help
  479. If you want to compile uClibc with NPTL support, then answer Y.
  480. endchoice
  481. config UCLIBC_HAS_THREADS
  482. def_bool y if !HAS_NO_THREADS
  483. config UCLIBC_HAS_TLS
  484. bool "Thread-Local Storage"
  485. depends on UCLIBC_HAS_THREADS_NATIVE
  486. help
  487. If you want to enable TLS support then answer Y.
  488. This is fast an efficient way to store per-thread local data
  489. which is not on stack. It needs __thread support enabled in
  490. gcc.
  491. config PTHREADS_DEBUG_SUPPORT
  492. bool "Build pthreads debugging support"
  493. depends on UCLIBC_HAS_THREADS
  494. help
  495. Say Y here if you wish to be able to debug applications that use
  496. uClibc's pthreads library. By enabling this option, a library
  497. named libthread_db will be built. This library will be dlopen()'d
  498. by gdb and will allow gdb to debug the threads in your application.
  499. IMPORTANT NOTE! Because gdb must dlopen() the libthread_db library,
  500. you must compile gdb with uClibc in order for pthread debugging to
  501. work properly.
  502. If you are doing development and want to debug applications using
  503. uClibc's pthread library, answer Y. Otherwise, answer N.
  504. config UCLIBC_HAS_SYSLOG
  505. bool "Syslog support"
  506. default y
  507. depends on UCLIBC_HAS_NETWORK_SUPPORT
  508. select UCLIBC_HAS_SOCKET
  509. help
  510. Support sending messages to the system logger.
  511. This requires socket-support.
  512. config UCLIBC_HAS_LFS
  513. def_bool y
  514. help
  515. Large file support (always enabled; config symbol retained for
  516. feature test to be compatible with uClibc).
  517. choice
  518. prompt "Malloc Implementation"
  519. default MALLOC if ! ARCH_USE_MMU
  520. default MALLOC_STANDARD if ARCH_USE_MMU
  521. config MALLOC
  522. bool "malloc"
  523. help
  524. "malloc" use mmap for all allocations and so works very well on
  525. MMU-less systems that do not support the brk() system call. It is
  526. pretty smart about reusing already allocated memory, and minimizing
  527. memory wastage.
  528. This is the default for uClinux MMU-less systems.
  529. config MALLOC_SIMPLE
  530. bool "malloc-simple"
  531. help
  532. "malloc-simple" is trivially simple and slow as molasses. It
  533. was written from scratch for uClibc, and is the simplest possible
  534. (and therefore smallest) malloc implementation.
  535. This uses only the mmap() system call to allocate and free memory,
  536. and does not use the brk() system call at all, making it a fine
  537. choice for MMU-less systems with very limited memory. It's 100%
  538. standards compliant, thread safe, very small, and releases freed
  539. memory back to the OS immediately rather than keeping it in the
  540. process's heap for reallocation. It is also VERY SLOW.
  541. config MALLOC_STANDARD
  542. bool "malloc-standard"
  543. depends on ARCH_USE_MMU
  544. help
  545. "malloc-standard" is derived from the public domain dlmalloc
  546. implementation by Doug Lea. It is quite fast, and is pretty smart
  547. about reusing already allocated memory, and minimizing memory
  548. wastage. This uses brk() for small allocations, while using mmap()
  549. for larger allocations. This is the default malloc implementation
  550. for uClibc.
  551. If unsure, answer "malloc-standard".
  552. endchoice
  553. config UCLIBC_DYNAMIC_ATEXIT
  554. bool "Dynamic atexit() Support"
  555. default y
  556. help
  557. When this option is enabled, uClibc will support an infinite number,
  558. of atexit() and on_exit() functions, limited only by your available
  559. memory. This can be important when uClibc is used with C++, since
  560. global destructors are implemented via atexit(), and it is quite
  561. possible to exceed the default number when this option is disabled.
  562. Enabling this option adds a few bytes, and more significantly makes
  563. atexit and on_exit depend on malloc, which can be bad when compiling
  564. static executables.
  565. Unless you use uClibc with C++, you should probably answer N.
  566. config UCLIBC_HAS_UTMPX
  567. bool "utmpx based support for tracking login/logouts to/from the system"
  568. help
  569. Answer y to enable support for accessing user accounting database.
  570. It can be used to track all login/logout to the system.
  571. config UCLIBC_HAS_UTMP
  572. bool "utmp support (XPG2 compat, SVr4 compat)"
  573. depends on UCLIBC_HAS_UTMPX
  574. help
  575. Answer y to enable legacy SVID support for accessing
  576. user accounting database:
  577. getutent(), getutid(), getutline(), pututline(),
  578. setutent(), endutent(), utmpname() in utmp.h
  579. It can be used to track all login/logout to the system.
  580. If unsure, answer N and use corresponding POSIX functions
  581. from utmpx.h
  582. config UCLIBC_SUSV2_LEGACY
  583. bool "Enable SuSv2 LEGACY functions"
  584. help
  585. Enable this option if you want to have SuSv2 LEGACY functions
  586. Currently applies to:
  587. valloc
  588. WARNING! ABI incompatibility.
  589. config UCLIBC_SUSV3_LEGACY
  590. bool "Enable SuSv3 LEGACY functions"
  591. #vfork,
  592. # h_errno
  593. # gethostbyaddr
  594. # gethostbyname
  595. help
  596. Enable this option if you want to have SuSv3 LEGACY functions
  597. in the library, else they are replaced by SuSv3 proposed macros.
  598. Currently applies to:
  599. bcmp, bcopy, bzero, index, rindex, ftime,
  600. bsd_signal, (ecvt), (fcvt), gcvt, (getcontext),
  601. (getwd), (makecontext),
  602. mktemp, (pthread_attr_getstackaddr), (pthread_attr_setstackaddr),
  603. scalb, (setcontext), (swapcontext), ualarm, usleep,
  604. wcswcs.
  605. WARNING! ABI incompatibility.
  606. config UCLIBC_HAS_CONTEXT_FUNCS
  607. bool "Use obsolescent context control functions"
  608. depends on UCLIBC_SUSV3_LEGACY && ARCH_HAS_UCONTEXT
  609. help
  610. Add into library the SuSv3 obsolescent functions used for context
  611. control. The setcontext family allows the implementation in C of
  612. advanced control flow patterns such as iterators, fibers, and
  613. coroutines. They may be viewed as an advanced version of
  614. setjmp/longjmp; whereas the latter allows only a single non-local jump
  615. up the stack, setcontext allows the creation of multiple cooperative
  616. threads of control, each with its own stack.
  617. These functions are: setcontext, getcontext, makecontext, swapcontext.
  618. config UCLIBC_SUSV3_LEGACY_MACROS
  619. bool "Enable SuSv3 LEGACY macros"
  620. help
  621. Enable this option if you want to have SuSv3 LEGACY macros.
  622. Currently applies to bcopy/bzero/bcmp/index/rindex et al.
  623. WARNING! ABI incompatibility.
  624. config UCLIBC_SUSV4_LEGACY
  625. bool "Enable SuSv4 LEGACY or obsolescent functions"
  626. help
  627. Enable this option if you want to have SuSv4 LEGACY functions
  628. and macros in the library.
  629. Currently applies to:
  630. - XSI functions:
  631. _longjmp, _setjmp, _tolower, _toupper, ftw, getitimer,
  632. gettimeofday, isascii, pthread_getconcurrency,
  633. pthread_setconcurrency, setitimer, setpgrp, sighold,
  634. sigignore, sigpause, sigrelse, sigset, siginterrupt,
  635. tempnam, toascii, ulimit.
  636. - Base functions:
  637. asctime, asctime_r, ctime, ctime_r, gets, rand_r,
  638. tmpnam, utime.
  639. WARNING! ABI incompatibility.
  640. config UCLIBC_STRICT_HEADERS
  641. bool "Hide structures and constants for unsupported features"
  642. help
  643. Hide structures and constants in headers that should not be used,
  644. because the respective feature is disabled.
  645. WARNING! enabling this option requires to patch many faulty apps,
  646. since they make (wrongly) use of these structures/constants,
  647. although the feature was disabled.
  648. config UCLIBC_HAS_STUBS
  649. bool "Provide stubs for unavailable functionality"
  650. help
  651. With this option uClibc provides non-functional stubs for
  652. functions which are impossible to implement on the target
  653. architecture. Otherwise, such functions are simply omitted.
  654. config UCLIBC_HAS_SHADOW
  655. bool "Shadow Password Support"
  656. default y
  657. help
  658. Answer N if you do not need shadow password support.
  659. Most people will answer Y.
  660. config UCLIBC_HAS_PROGRAM_INVOCATION_NAME
  661. bool "Support for program_invocation_name"
  662. help
  663. Support for the GNU-specific program_invocation_name and
  664. program_invocation_short_name strings. Some GNU packages
  665. (like tar and coreutils) utilize these for extra useful
  666. output, but in general are not required.
  667. At startup, these external strings are automatically set
  668. up based on the value of ARGV[0].
  669. If unsure, just answer N.
  670. config UCLIBC_HAS___PROGNAME
  671. bool "Support for __progname"
  672. default y
  673. help
  674. Some packages (like openssh) like to peek into internal libc
  675. symbols to make their output a bit more user friendly.
  676. At startup, __progname is automatically set up based on the
  677. value of ARGV[0].
  678. If unsure, just answer N.
  679. config UCLIBC_HAS_PTY
  680. bool "Support for pseudo-terminals"
  681. default y
  682. help
  683. This enables support for pseudo-terminals (see man 4 pts
  684. and man 7 pty).
  685. If unsure, just answer Y.
  686. config ASSUME_DEVPTS
  687. bool "Assume that /dev/pts is a devpts or devfs file system"
  688. default y
  689. depends on UCLIBC_HAS_PTY
  690. help
  691. Enable this if /dev/pts is on a devpts or devfs filesystem. Both
  692. these filesystems automatically manage permissions on the /dev/pts
  693. devices. You may need to mount your devpts or devfs filesystem on
  694. /dev/pts for this to work.
  695. Most people should answer Y.
  696. config UNIX98PTY_ONLY
  697. bool "Support only Unix 98 PTYs"
  698. default y
  699. depends on UCLIBC_HAS_PTY
  700. help
  701. If you want to support only Unix 98 PTYs enable this. Some older
  702. applications may need this disabled and will thus use legacy BSD
  703. style PTY handling which is more complex and also bigger than
  704. Unix 98 PTY handling.
  705. For most current programs, you can generally answer Y.
  706. if UNIX98PTY_ONLY
  707. config UCLIBC_HAS_GETPT
  708. bool "Support getpt() (glibc-compat)"
  709. depends on UCLIBC_HAS_PTY
  710. help
  711. Some packages may need getpt().
  712. All of those are non-standard and can be considered
  713. GNU/libc compatibility.
  714. Either use posix_openpt() or just open /dev/ptmx yourself.
  715. If unsure, just say N.
  716. endif
  717. if !UNIX98PTY_ONLY
  718. # Have to use __libc_ptyname{1,2}[] and related bloat
  719. config UCLIBC_HAS_GETPT
  720. def_bool y
  721. endif
  722. config UCLIBC_HAS_LIBUTIL
  723. bool "Provide libutil library and functions"
  724. depends on UCLIBC_HAS_PTY
  725. help
  726. Provide a libutil library.
  727. This non-standard conforming library provides the following
  728. utility functions:
  729. forkpty(): combines openpty(), fork(2), and login_tty() to
  730. create a new process operating in a pseudo-terminal.
  731. login(): write utmp and wtmp entries
  732. login_tty(): prepares for a login on the tty fd by creating a
  733. new session, making fd the controlling terminal for
  734. the calling process, setting fd to be the standard
  735. input, output, and error streams of the current
  736. process, and closing fd.
  737. logout(): write utmp and wtmp entries
  738. logwtmp(): constructs a utmp structure and calls updwtmp() to
  739. append the structure to the utmp file.
  740. openpty(): finds an available pseudo-terminal and returns
  741. file descriptors for the master and slave
  742. This library adds about 3k-4k to your system.
  743. config UCLIBC_HAS_TM_EXTENSIONS
  744. bool "Support 'struct tm' timezone extension fields"
  745. default y
  746. help
  747. Enabling this option adds fields to 'struct tm' in time.h for
  748. tracking the number of seconds east of UTC, and an abbreviation for
  749. the current timezone. These fields are not specified by the SuSv3
  750. standard, but they are commonly used in both GNU and BSD application
  751. code.
  752. To strictly follow the SuSv3 standard, leave this disabled.
  753. Most people will probably want to answer Y.
  754. config UCLIBC_HAS_TZ_CACHING
  755. bool "Enable caching of the last valid timezone 'TZ' string"
  756. default y
  757. help
  758. Answer Y to enable caching of the last valid 'TZ' string describing
  759. the timezone setting. This allows a quick string compare to avoid
  760. repeated parsing of unchanged 'TZ' strings when tzset() is called.
  761. Most people will answer Y.
  762. config UCLIBC_HAS_TZ_FILE
  763. bool "Enable '/etc/TZ' file support to set a default timezone (uClibc-specific)"
  764. default y
  765. help
  766. Answer Y to enable the setting of a default timezone for uClibc.
  767. Ordinarily, uClibc gets the timezone information exclusively from the
  768. 'TZ' environment variable. In particular, there is no support for
  769. the zoneinfo directory tree or the /etc/timezone file used by glibc.
  770. With this option enabled, uClibc will use the value stored in the
  771. file '/etc/TZ' (default path) to obtain timezone information if the
  772. 'TZ' environment variable is missing or has an invalid value. The
  773. file consists of a single line (newline required) of text describing
  774. the timezone in the format specified for the TZ environment variable.
  775. Doing 'echo CST6CDT > /etc/TZ' is enough to create a valid file.
  776. See
  777. http://www.opengroup.org/onlinepubs/007904975/basedefs/xbd_chap08.html
  778. for details on valid settings of 'TZ'.
  779. Most people will answer Y.
  780. config UCLIBC_HAS_TZ_FILE_READ_MANY
  781. bool "Repeatedly read the '/etc/TZ' file"
  782. depends on UCLIBC_HAS_TZ_FILE
  783. default y
  784. help
  785. Answer Y to enable repeated reading of the '/etc/TZ' file even after
  786. a valid value has been read. This incurs the overhead of an
  787. open/read/close for each tzset() call (explicit or implied). However,
  788. setting this will allow applications to update their timezone
  789. information if the contents of the file change.
  790. Most people will answer Y.
  791. config UCLIBC_TZ_FILE_PATH
  792. string "Path to the 'TZ' file for setting the global timezone"
  793. depends on UCLIBC_HAS_TZ_FILE
  794. default "/etc/TZ"
  795. help
  796. This is the path to the 'TZ' file.
  797. Most people will use the default of '/etc/TZ'.
  798. config UCLIBC_FALLBACK_TO_ETC_LOCALTIME
  799. bool "Use /etc/localtime as a fallback"
  800. depends on UCLIBC_HAS_TZ_FILE
  801. default y
  802. help
  803. Answer Y to try to use /etc/localtime file.
  804. On glibc systems this file (if it is in TZif2 format)
  805. contains timezone string at the end.
  806. Most people will answer Y.
  807. endmenu
  808. menu "Advanced Library Settings"
  809. config UCLIBC_PWD_BUFFER_SIZE
  810. int "Buffer size for getpwnam() and friends"
  811. default 256
  812. range 12 1024
  813. help
  814. This sets the value of the buffer size for getpwnam() and friends.
  815. By default, this is 256. (For reference, glibc uses 1024).
  816. The value can be found using sysconf() with the _SC_GETPW_R_SIZE_MAX
  817. parameter.
  818. config UCLIBC_GRP_BUFFER_SIZE
  819. int "Buffer size for getgrnam() and friends"
  820. default 256
  821. range 12 1024
  822. help
  823. This sets the value of the buffer size for getgrnam() and friends.
  824. By default, this is 256. (For reference, glibc uses 1024).
  825. The value can be found using sysconf() with the _SC_GETGR_R_SIZE_MAX
  826. parameter.
  827. comment "Support various families of functions"
  828. config UCLIBC_LINUX_SPECIFIC
  829. bool "Linux specific functions"
  830. default y
  831. help
  832. accept4(), bdflush(),
  833. capget(), capset(), eventfd(), fallocate(),
  834. fstatfs(), getrandom(), inotify_*(), ioperm(), iopl(),
  835. madvise(), modify_ldt(), pipe2(), personality(),
  836. prctl()/arch_prctl(), pivot_root(), modify_ldt(),
  837. ppoll(), readahead(), reboot(), remap_file_pages(),
  838. sched_getaffinity(), sched_setaffinity(), sendfile(),
  839. setfsgid(), setfsuid(), setresgid(), setresuid(),
  840. splice(), vmsplice(), tee(), signalfd(), statfs(),
  841. swapoff(), swapon(), sync_file_range(), syncfs(),
  842. _sysctl(), sysinfo(), timerfd_*(), vhangup(), umount(),
  843. umount2()
  844. config UCLIBC_HAS_GNU_ERROR
  845. bool "Support GNU extensions for error-reporting"
  846. default y
  847. help
  848. Support for the GNU-specific error(), error_at_line(),
  849. void (* error_print_progname)(), error_message_count
  850. functions and variables. Some GNU packages
  851. utilize these for extra useful output, but in general
  852. are not required.
  853. If unsure, just answer N.
  854. config UCLIBC_BSD_SPECIFIC
  855. bool "BSD specific functions"
  856. default y
  857. help
  858. mincore(), getdomainname(), setdomainname()
  859. If unsure, say N.
  860. config UCLIBC_HAS_BSD_ERR
  861. bool "BSD err functions"
  862. default y
  863. help
  864. These functions are non-standard BSD extensions.
  865. err(), errx(), warn(), warnx(), verr(), verrx(), vwarn(), vwarnx()
  866. If unsure, say N.
  867. config UCLIBC_HAS_OBSOLETE_BSD_SIGNAL
  868. bool "BSD obsolete signal functions"
  869. help
  870. These functions are provided as a compatibility interface for
  871. programs that make use of the historical System V signal API.
  872. This API is obsolete:
  873. new applications should use the POSIX signal API (sigaction(2),
  874. sigprocmask(2), etc.).
  875. Affected functions:
  876. sigset(), sighold(), sigrelse(), sigignore()
  877. If unsure, say N.
  878. config UCLIBC_HAS_BSD_B64_NTOP_B64_PTON
  879. bool "Support b64_ntop(), b64_pton() (bsd-compat)"
  880. help
  881. Answer Y if you need additional BSD compatibility
  882. (e.g. for openbsd-netcat).
  883. Most people will say N.
  884. config UCLIBC_HAS_OBSOLETE_SYSV_SIGNAL
  885. bool "SYSV obsolete signal functions"
  886. help
  887. Use of sysv_signal() should be avoided; use sigaction(2) instead.
  888. If unsure, say N.
  889. config UCLIBC_NTP_LEGACY
  890. bool "ntp_*() aliases"
  891. help
  892. Provide legacy aliases for ntp functions:
  893. ntp_adjtime(), ntp_gettime()
  894. It is safe to say N here.
  895. config UCLIBC_SV4_DEPRECATED
  896. bool "Enable SVr4 deprecated functions"
  897. help
  898. These functions are DEPRECATED in System V release 4.
  899. Say N unless you desparately need one of the functions below:
  900. ustat() [use statfs(2) in your code instead]
  901. config UCLIBC_HAS_REALTIME
  902. bool "Realtime-related family of SUSv functions"
  903. default y
  904. help
  905. These functions are part of the Timers option and need not
  906. be available on all implementations.
  907. Includes AIO, message-queue, scheduler, semaphore functions:
  908. aio.h
  909. mqueue.h
  910. sched.h
  911. semaphore.h
  912. aio_cancel()
  913. aio_error()
  914. aio_fsync()
  915. aio_read()
  916. lio_listio()
  917. aio_return()
  918. aio_suspend()
  919. aio_write()
  920. clock_getres(), clock_gettime(), clock_settime()
  921. fdatasync()
  922. mlockall(), munlockall()
  923. mlock(), munlock()
  924. mq_close()
  925. mq_getattr()
  926. mq_notify()
  927. mq_open()
  928. mq_receive()
  929. mq_send()
  930. mq_setattr()
  931. mq_unlink()
  932. nanosleep()
  933. sched_getparam()
  934. sched_get_priority_max(), sched_get_priority_min()
  935. sched_getscheduler()
  936. sched_rr_get_interval()
  937. sched_setparam()
  938. sched_setscheduler()
  939. sem_close()
  940. sem_destroy()
  941. sem_getvalue()
  942. sem_init()
  943. sem_open()
  944. sem_post()
  945. sem_trywait(), sem_wait()
  946. sem_unlink()
  947. sigqueue()
  948. sigtimedwait(), sigwaitinfo()
  949. timer_create()
  950. timer_delete()
  951. timer_getoverrun(), timer_gettime(), timer_settime()
  952. config UCLIBC_HAS_ADVANCED_REALTIME
  953. bool "Advanced realtime-related family of SUSv functions"
  954. default y
  955. depends on UCLIBC_HAS_REALTIME
  956. help
  957. These functions are part of the Timers option and need not
  958. be available on all implementations.
  959. clock_getcpuclockid()
  960. clock_nanosleep()
  961. mq_timedreceive()
  962. mq_timedsend()
  963. posix_fadvise()
  964. posix_fallocate()
  965. posix_madvise()
  966. posix_memalign()
  967. posix_mem_offset()
  968. posix_spawnattr_destroy(), posix_spawnattr_init()
  969. posix_spawnattr_getflags(), posix_spawnattr_setflags()
  970. posix_spawnattr_getpgroup(), posix_spawnattr_setpgroup()
  971. posix_spawnattr_getschedparam(), posix_spawnattr_setschedparam()
  972. posix_spawnattr_getschedpolicy(), posix_spawnattr_setschedpolicy()
  973. posix_spawnattr_getsigdefault(), posix_spawnattr_setsigdefault()
  974. posix_spawnattr_getsigmask(), posix_spawnattr_setsigmask()
  975. posix_spawn_file_actions_addclose()
  976. posix_spawn_file_actions_adddup2()
  977. posix_spawn_file_actions_addopen()
  978. posix_spawn_file_actions_destroy()
  979. posix_spawn_file_actions_init()
  980. posix_spawn()
  981. posix_spawnp()
  982. posix_typed_mem_get_info()
  983. pthread_mutex_timedlock()
  984. sem_timedwait()
  985. #config UCLIBC_HAS_TERMIOS
  986. # bool "termios functions"
  987. # default y
  988. # help
  989. # Get and set terminal attributes, line control, get and set baud
  990. # rate.
  991. # termios(), tcgetattr(), tcsetattr(), tcsendbreak(), tcdrain(),
  992. # tcflush(), tcflow(), cfmakeraw(), cfgetospeed(), cfgetispeed(),
  993. # cfsetispeed(), cfsetospeed(), cfsetspeed()
  994. #
  995. # If unsure, say Y.
  996. config UCLIBC_HAS_EPOLL
  997. bool "epoll"
  998. default y
  999. help
  1000. epoll_create(), epoll_ctl(), epoll_wait() functions.
  1001. config UCLIBC_HAS_XATTR
  1002. bool "Extended Attributes"
  1003. default y
  1004. help
  1005. Extended Attributes support.
  1006. setxattr()
  1007. lsetxattr()
  1008. fsetxattr()
  1009. getxattr()
  1010. lgetxattr()
  1011. fgetxattr()
  1012. listxattr()
  1013. llistxattr()
  1014. flistxattr()
  1015. removexattr()
  1016. lremovexattr()
  1017. fremovexattr()
  1018. Say N unless you need support for extended attributes and the
  1019. filesystems do actually support them.
  1020. config UCLIBC_HAS_PROFILING
  1021. bool "Profiling support"
  1022. default y
  1023. help
  1024. gcc's -finstrument-functions needs these.
  1025. Most people can safely answer N.
  1026. config UCLIBC_HAS_CRYPT_IMPL
  1027. bool "libcrypt support"
  1028. default y
  1029. help
  1030. libcrypt contains crypt(), setkey() and encrypt()
  1031. config UCLIBC_HAS_SHA256_CRYPT_IMPL
  1032. bool "libcrypt SHA256 support"
  1033. depends on UCLIBC_HAS_CRYPT_IMPL
  1034. help
  1035. This adds support for SHA256 password hashing via the crypt() function.
  1036. Say N here if you do not need SHA256 crypt support.
  1037. config UCLIBC_HAS_SHA512_CRYPT_IMPL
  1038. bool "libcrypt SHA512 support"
  1039. depends on UCLIBC_HAS_CRYPT_IMPL
  1040. help
  1041. This adds support for SHA512 password hashing via the crypt() function.
  1042. Say N here if you do not need SHA512 crypt support.
  1043. config UCLIBC_HAS_CRYPT_STUB
  1044. bool "libcrypt stubs"
  1045. default y
  1046. depends on !UCLIBC_HAS_CRYPT_IMPL
  1047. help
  1048. Standards mandate that crypt(3) provides a stub if it is unavailable.
  1049. If you enable this option then stubs for
  1050. crypt(), setkey() and encrypt()
  1051. will be provided in a small libcrypt.
  1052. config UCLIBC_HAS_CRYPT
  1053. def_bool y
  1054. depends on UCLIBC_HAS_CRYPT_IMPL || UCLIBC_HAS_CRYPT_STUB
  1055. endmenu
  1056. menuconfig UCLIBC_HAS_NETWORK_SUPPORT
  1057. bool "Networking Support"
  1058. default y
  1059. help
  1060. Say N here if you do not need network support.
  1061. if UCLIBC_HAS_NETWORK_SUPPORT
  1062. config UCLIBC_HAS_SOCKET
  1063. bool "Socket support"
  1064. default y
  1065. help
  1066. If you want to include support for sockets then answer Y.
  1067. config UCLIBC_HAS_IPV4
  1068. bool "IP version 4 support"
  1069. default y
  1070. select UCLIBC_HAS_SOCKET
  1071. help
  1072. If you want to include support for the Internet Protocol
  1073. (IP version 4) then answer Y.
  1074. Most people will say Y.
  1075. config UCLIBC_HAS_IPV6
  1076. bool "IP version 6 support"
  1077. select UCLIBC_HAS_SOCKET
  1078. help
  1079. If you want to include support for the next version of the Internet
  1080. Protocol (IP version 6) then answer Y.
  1081. Most people should answer N.
  1082. config UCLIBC_USE_NETLINK
  1083. bool "Use netlink to query interfaces"
  1084. depends on UCLIBC_HAS_SOCKET
  1085. help
  1086. In newer versions of Linux (2.4.17+), support was added for querying
  1087. network device information via netlink rather than the old style
  1088. ioctl's. Most of the time, the older ioctl style is sufficient (and
  1089. it is smaller than netlink), but if you find that not all of your
  1090. devices are being returned by the if_nameindex() function, you will
  1091. have to use the netlink implementation.
  1092. Most people can safely answer N.
  1093. config UCLIBC_SUPPORT_AI_ADDRCONFIG
  1094. bool "Support the AI_ADDRCONFIG flag"
  1095. depends on UCLIBC_USE_NETLINK
  1096. help
  1097. The implementation of AI_ADDRCONFIG is aligned with the glibc
  1098. implementation using netlink to query interfaces to find both
  1099. ipv4 and ipv6 support. This is only needed if an application uses
  1100. the AI_ADDRCONFIG flag.
  1101. Most people can safely answer N.
  1102. config UCLIBC_HAS_BSD_RES_CLOSE
  1103. bool "Support res_close() (bsd-compat)"
  1104. help
  1105. Answer Y if you desperately want to support BSD compatibility in
  1106. the network code.
  1107. Most people will say N.
  1108. config UCLIBC_HAS_COMPAT_RES_STATE
  1109. bool "Use compatible but bloated _res"
  1110. default y
  1111. help
  1112. Answer Y if you build network utilities and they muck with resolver
  1113. internals a lot (_res global structure). uclibc does not use most
  1114. of _res.XXX fields, and with this option OFF they won't even exist.
  1115. Which will make e.g. dig build fail.
  1116. Answering N saves around 400 bytes in bss.
  1117. config UCLIBC_HAS_EXTRA_COMPAT_RES_STATE
  1118. bool "Use extra compatible but extra bloated _res"
  1119. help
  1120. Answer Y if selecting UCLIBC_HAS_COMPAT_RES_STATE is not enough.
  1121. As far as I can say, this should never be needed.
  1122. config UCLIBC_HAS_RESOLVER_SUPPORT
  1123. bool "DNS resolver functions"
  1124. select UCLIBC_HAS_COMPAT_RES_STATE
  1125. depends on UCLIBC_HAS_IPV4 || UCLIBC_HAS_IPV6
  1126. help
  1127. Provide implementations for DNS resolver functions.
  1128. In particular, the following functions will be added to the
  1129. library:
  1130. ns_skiprr, ns_initparse, ns_parserr, ns_msg_getflag,
  1131. res_mkquery, res_init, res_ninit, res_close, res_nclose
  1132. res_query, res_search, res_querydomain,
  1133. dn_expand, dn_comp,
  1134. ns_name_uncompress, ns_name_ntop, ns_name_pton, ns_name_unpack,
  1135. ns_name_pack, ns_name_compress, ns_name_skip, dn_skipname,
  1136. ns_get16, ns_get32, ns_put16, ns_put32
  1137. choice
  1138. prompt "DNS Query ID generation"
  1139. default UCLIBC_DNSRAND_MODE_PRNGPLUS
  1140. help
  1141. Control how successive dns query ids' are generated during
  1142. dns lookup.
  1143. config UCLIBC_DNSRAND_MODE_URANDOM
  1144. bool "urandom"
  1145. help
  1146. "urandom" uses /dev/urandom available under many unix flavours
  1147. to generate dns query id. This can generate good random ids,
  1148. by dipping into the entropy pool maintained by the system.
  1149. However this is relatively slow compared to the other options,
  1150. as it may involve cryptographic operations internally and
  1151. kernel-userspace handshake.
  1152. config UCLIBC_DNSRAND_MODE_CLOCK
  1153. bool "clock"
  1154. depends on UCLIBC_HAS_REALTIME
  1155. help
  1156. "clock" uses CLOCK_REALTIME of the system to generate plausibly
  1157. random dns query id. Systems require to have clock source with
  1158. nanosec granularity mapped to this clock id for this to generate
  1159. plausibly random values. However has processor and io performances
  1160. improve in future, its effectiveness can get impacted.
  1161. config UCLIBC_DNSRAND_MODE_PRNGPLUS
  1162. bool "prngplus"
  1163. help
  1164. "prngplus" uses random prng available within uclibc, to indirectly
  1165. generate the dns query id. This tries to provide a good balance
  1166. between speed and randomness to an extent. It periodically reseeds
  1167. the prng using random value generated from either the urandom or
  1168. else the clock, if either of them is available. Additionally applies
  1169. transform (one way, if possible) on internal generated random values.
  1170. These make it difficult to infer internal state of prng from unbroken
  1171. sequences of exposed random values.
  1172. This is the default.
  1173. config UCLIBC_DNSRAND_MODE_SIMPLECOUNTER
  1174. bool "simplecounter"
  1175. help
  1176. "simplecounter" uses a simple counter to generate dns query id.
  1177. This is a very simple logic and can be subjected to dns poison
  1178. attack relatively easily.
  1179. It is recommended to avoid this option.
  1180. endchoice
  1181. endif
  1182. menu "String and Stdio Support"
  1183. config UCLIBC_HAS_STRING_GENERIC_OPT
  1184. bool "Use faster (but larger) generic string functions"
  1185. default y
  1186. help
  1187. Answer Y to use the (tweaked) glibc generic string functions.
  1188. In general, they are faster (but 3-5K larger) than the base
  1189. uClibc string functions which are optimized solely for size.
  1190. Many people will answer Y.
  1191. config UCLIBC_HAS_STRING_ARCH_OPT
  1192. bool "Use arch-specific assembly string functions (where available)"
  1193. default y
  1194. help
  1195. Answer Y to use any archtecture-specific assembly language string
  1196. functions available for this target plaform.
  1197. Note that assembly implementations are not available for all string
  1198. functions, so some generic (written in C) string functions may
  1199. still be used.
  1200. These are small and fast, the only reason _not_ to say Y here is
  1201. for debugging purposes.
  1202. config UCLIBC_HAS_STDIO_FUTEXES
  1203. bool "Use futexes for multithreaded I/O locking"
  1204. depends on UCLIBC_HAS_THREADS_NATIVE
  1205. help
  1206. If you want to compile uClibc to use futexes for low-level
  1207. I/O locking, answer Y. Otherwise, answer N.
  1208. config UCLIBC_HAS_CTYPE_TABLES
  1209. bool "Use Table Versions Of 'ctype.h' Functions."
  1210. default y
  1211. help
  1212. Answer Y to use table versions of the 'ctype.h' functions.
  1213. While the non-table versions are often smaller when building
  1214. statically linked apps, they work only in stub locale mode.
  1215. Most people will answer Y.
  1216. config UCLIBC_HAS_CTYPE_SIGNED
  1217. bool "Support Signed Characters In 'ctype.h' Functions."
  1218. depends on UCLIBC_HAS_CTYPE_TABLES
  1219. default y
  1220. help
  1221. Answer Y to enable support for passing signed char values to
  1222. the 'ctype.h' functions. ANSI/ISO C99 and SUSv3 specify that
  1223. these functions are only defined for unsigned char values and
  1224. EOF. However, glibc allows negative signed char values as well
  1225. in order to support 'broken old programs'.
  1226. Most people will answer Y.
  1227. choice
  1228. prompt "ctype argument checking"
  1229. depends on UCLIBC_HAS_CTYPE_TABLES
  1230. default UCLIBC_HAS_CTYPE_UNSAFE
  1231. help
  1232. Please select the invalid arg behavior you want for the 'ctype'
  1233. functions.
  1234. The 'ctype' functions are now implemented using table lookups, with
  1235. the arg being the index. This can result in incorrect memory accesses
  1236. or even segfaults for args outside of the allowed range.
  1237. NOTE: This only affects the 'ctype' _functions_. It does not affect
  1238. the macro implementations.
  1239. config UCLIBC_HAS_CTYPE_UNSAFE
  1240. bool "Do not check -- unsafe"
  1241. config UCLIBC_HAS_CTYPE_CHECKED
  1242. bool "Detect and handle appropriately"
  1243. config UCLIBC_HAS_CTYPE_ENFORCED
  1244. bool "Issue a diagnostic and abort()"
  1245. endchoice
  1246. config UCLIBC_HAS_WCHAR
  1247. bool "Wide Character Support"
  1248. help
  1249. Answer Y to enable wide character support. This will make uClibc
  1250. much larger. It is also currently required for locale support.
  1251. Most people will answer N.
  1252. config UCLIBC_HAS_LIBICONV
  1253. bool "Iconv Support"
  1254. select UCLIBC_HAS_WCHAR
  1255. help
  1256. Add tiny iconv support for charset conversion from and to UTF-8.
  1257. config UCLIBC_HAS_LIBINTL
  1258. bool "Intl stubs support"
  1259. help
  1260. If you enable this option you get stubs for the gettext family of
  1261. functions.
  1262. config UCLIBC_HAS_LOCALE
  1263. bool "Locale Support"
  1264. select UCLIBC_HAS_WCHAR
  1265. select UCLIBC_HAS_CTYPE_TABLES
  1266. select UCLIBC_HAS_LIBICONV
  1267. help
  1268. uClibc now has full ANSI/ISO C99 locale support (except for
  1269. wcsftime() and collating items in regex). Be aware that enabling
  1270. this option will make uClibc much larger.
  1271. Enabling UCLIBC_HAS_LOCALE with the default set of supported locales
  1272. (169 UTF-8 locales, and 144 locales for other codesets) will enlarge
  1273. uClibc by around 300k. You can reduce this size by building your own
  1274. custom set of locate data (see extra/locale/LOCALES for details).
  1275. uClibc's locale support is still under development. For example,
  1276. codesets using shift states are not currently supported. Support is
  1277. planned in the next iteration of locale support.
  1278. Answer Y to enable locale support. Most people will answer N.
  1279. choice
  1280. prompt "Locale data"
  1281. depends on UCLIBC_HAS_LOCALE
  1282. default UCLIBC_BUILD_MINIMAL_LOCALE
  1283. config UCLIBC_BUILD_MINIMAL_LOCALE
  1284. bool "Only selected locales"
  1285. depends on UCLIBC_HAS_LOCALE
  1286. help
  1287. If you do not need all locales that are available on your
  1288. host-box, then set this to 'Y'.
  1289. config UCLIBC_BUILD_ALL_LOCALE
  1290. bool "All locales"
  1291. depends on UCLIBC_HAS_LOCALE
  1292. help
  1293. This builds all the locales that are available on your
  1294. host-box.
  1295. endchoice
  1296. config UCLIBC_BUILD_MINIMAL_LOCALES
  1297. string "locales to use"
  1298. depends on UCLIBC_BUILD_MINIMAL_LOCALE
  1299. default "en_US"
  1300. help
  1301. Space separated list of locales to use.
  1302. E.g.:
  1303. en_US en_GB de_AT
  1304. default:
  1305. en_US
  1306. config UCLIBC_HAS_XLOCALE
  1307. bool "Extended Locale Support (experimental/incomplete)"
  1308. depends on UCLIBC_HAS_LOCALE
  1309. help
  1310. Answer Y to enable extended locale support similar to that provided
  1311. by glibc. This is primarily intended to support libstd++
  1312. functionality.
  1313. However, it also allows thread-specific locale selection via
  1314. uselocale().
  1315. Most people will answer N.
  1316. config UCLIBC_HAS_HEXADECIMAL_FLOATS
  1317. bool "Support hexadecimal float notation"
  1318. depends on UCLIBC_HAS_CTYPE_TABLES
  1319. depends on UCLIBC_HAS_FLOATS
  1320. help
  1321. Answer Y to enable support for hexadecimal float notation in the
  1322. (wchar and) char string to floating point conversion functions, as
  1323. well as support for the %a and %A conversion specifiers in the
  1324. *printf() and *scanf() functions.
  1325. Most people will answer N.
  1326. config UCLIBC_HAS_GLIBC_DIGIT_GROUPING
  1327. bool "Support glibc's \"'\" flag for allowing locale-specific digit grouping"
  1328. depends on UCLIBC_HAS_LOCALE
  1329. depends on UCLIBC_HAS_FLOATS
  1330. help
  1331. Answer Y to enable support for glibc's \"'\" flag for allowing
  1332. locale-specific digit grouping in base 10 integer conversions and
  1333. appropriate floating point conversions in the *printf() and *scanf()
  1334. functions.
  1335. Most people will answer N.
  1336. config UCLIBC_HAS_SCANF_LENIENT_DIGIT_GROUPING
  1337. bool "Do not require digit grouping when the \"'\" flag is specified"
  1338. depends on UCLIBC_HAS_GLIBC_DIGIT_GROUPING
  1339. default y
  1340. help
  1341. Answer Y to make digit grouping optional when the \"'\" flag is
  1342. specified.
  1343. This is the standard glibc behavior. If the initial string of digits
  1344. exceeds the maximum group number, the input will be treated as a
  1345. normal non-grouped number.
  1346. Most people will answer N.
  1347. config UCLIBC_HAS_GLIBC_CUSTOM_PRINTF
  1348. bool "Support glibc's register_printf_function() (glibc-compat)"
  1349. depends on !USE_OLD_VFPRINTF
  1350. help
  1351. Answer Y to support glibc's register_printf_function() to allow an
  1352. application to add its own printf conversion specifiers.
  1353. parse_printf_format() is also enabled.
  1354. NOTE: Limits the number or registered specifiers to 10.
  1355. NOTE: Requires new conversion specifiers to be ASCII
  1356. characters (0-0x7f). This is to avoid problems with processing
  1357. format strings in locales with different multibyte conversions.
  1358. Most people will answer N.
  1359. config USE_OLD_VFPRINTF
  1360. bool "Use the old vfprintf implementation"
  1361. depends on !UCLIBC_HAS_WCHAR
  1362. help
  1363. Set to true to use the old vfprintf instead of the new. This is
  1364. roughly C89 compliant with some extensions, and is much smaller.
  1365. However, it does not support wide chars, positional args, or glibc
  1366. custom printf specifiers.
  1367. Most people will answer N.
  1368. config UCLIBC_PRINTF_SCANF_POSITIONAL_ARGS
  1369. int "Maximum number of positional args. Either 0 or >= 9."
  1370. depends on !USE_OLD_VFPRINTF
  1371. default 9
  1372. help
  1373. Set the maximum number of positional args supported by the
  1374. printf/scanf functions. The Single Unix Specification Version 3
  1375. requires a minimum value of 9. Setting this to a value lower than
  1376. 9 will disable positional arg support and cause the NL_ARGMAX macro
  1377. in limits.h to be #undef'd.
  1378. WARNING! The workspace to support positional args is currently
  1379. allocated on the stack. You probably don't want to set
  1380. this to too high a value.
  1381. Most people will answer 9.
  1382. choice
  1383. prompt "Stdio buffer size"
  1384. default UCLIBC_HAS_STDIO_BUFSIZ_4096
  1385. help
  1386. Please select a value for BUFSIZ. This will be used by the
  1387. stdio subsystem as the default buffer size for a file, and
  1388. affects fopen(), setvbuf(), etc.
  1389. NOTE: Setting this to 'none' will disable buffering completely.
  1390. However, BUFSIZ will still be defined in stdio.h as 256 because
  1391. many applications use this value.
  1392. config UCLIBC_HAS_STDIO_BUFSIZ_NONE
  1393. bool "none (WARNING - BUFSIZ will be 256 in stdio.h)"
  1394. depends on !UCLIBC_HAS_WCHAR
  1395. config UCLIBC_HAS_STDIO_BUFSIZ_256
  1396. bool "256 (minimum ANSI/ISO C99 value)"
  1397. config UCLIBC_HAS_STDIO_BUFSIZ_512
  1398. bool "512"
  1399. config UCLIBC_HAS_STDIO_BUFSIZ_1024
  1400. bool "1024"
  1401. config UCLIBC_HAS_STDIO_BUFSIZ_2048
  1402. bool "2048"
  1403. config UCLIBC_HAS_STDIO_BUFSIZ_4096
  1404. bool "4096"
  1405. config UCLIBC_HAS_STDIO_BUFSIZ_8192
  1406. bool "8192"
  1407. # If you add more choices, you will need to update uClibc_stdio.h.
  1408. endchoice
  1409. choice
  1410. prompt "Stdio builtin buffer size (uClibc-specific)"
  1411. depends on !UCLIBC_HAS_STDIO_BUFSIZ_NONE
  1412. default UCLIBC_HAS_STDIO_BUILTIN_BUFFER_NONE
  1413. help
  1414. When a FILE is created with fopen(), an attempt is made to allocate
  1415. a BUFSIZ buffer for it. If the allocation fails, fopen() will still
  1416. succeed but the FILE will be unbuffered.
  1417. This option adds a small amount of space to each FILE to act as an
  1418. emergency buffer in the event of a buffer allocation failure.
  1419. Most people will answer None.
  1420. config UCLIBC_HAS_STDIO_BUILTIN_BUFFER_NONE
  1421. bool "None"
  1422. config UCLIBC_HAS_STDIO_BUILTIN_BUFFER_4
  1423. bool "4"
  1424. config UCLIBC_HAS_STDIO_BUILTIN_BUFFER_8
  1425. bool "8"
  1426. # If you add more choices, you will need to update uClibc_stdio.h.
  1427. endchoice
  1428. config UCLIBC_HAS_STDIO_SHUTDOWN_ON_ABORT
  1429. bool "Attempt to shutdown stdio subsystem when abort() is called."
  1430. help
  1431. ANSI/ISO C99 requires abort() to be asyn-signal-safe. So there was
  1432. a behavioral change made in SUSv3. Previously, abort() was required
  1433. to have the affect of fclose() on all open streams. The wording has
  1434. been changed to "may" from "shall".
  1435. Most people will answer N.
  1436. config UCLIBC_HAS_STDIO_GETC_MACRO
  1437. bool "Provide a macro version of getc()"
  1438. depends on !UCLIBC_HAS_STDIO_BUFSIZ_NONE
  1439. default y
  1440. help
  1441. Provide a macro version of getc().
  1442. Most people will answer Y.
  1443. config UCLIBC_HAS_STDIO_PUTC_MACRO
  1444. bool "Provide a macro version of putc()"
  1445. depends on !UCLIBC_HAS_STDIO_BUFSIZ_NONE
  1446. default y
  1447. help
  1448. Provide a macro version of putc().
  1449. Most people will answer Y.
  1450. config UCLIBC_HAS_STDIO_AUTO_RW_TRANSITION
  1451. bool "Support auto-r/w transition"
  1452. default y
  1453. help
  1454. Answer Y to enable the stdio subsystem to automaticly transition
  1455. between reading and writing. This relaxes the ANSI/ISO C99
  1456. requirement:
  1457. When a file is opened with update mode ('+' as the second or third
  1458. character in the list of mode argument values), both input and output
  1459. may be performed on the associated stream. However, output shall not
  1460. be directly followed by input without an intervening call to the
  1461. fflush function or to a file positioning function (fseek, fsetpos,
  1462. or rewind), and input shall not be directly followed by output without
  1463. an intervening call to a file positioning function, unless the input
  1464. operation encounters end­of­file.
  1465. Most people will answer Y.
  1466. config UCLIBC_HAS_FOPEN_LARGEFILE_MODE
  1467. bool "Support an fopen() 'F' flag for large file mode (uClibc-specific)"
  1468. help
  1469. Answer Y to enable a uClibc-specific extension to allow passing an
  1470. additional 'F' flag in the mode string for fopen() to specify that
  1471. the file should be open()ed with the O_LARGEFILE flag set.
  1472. Most people will answer N.
  1473. config UCLIBC_HAS_FOPEN_EXCLUSIVE_MODE
  1474. bool "Support an fopen() 'x' flag for exclusive mode (glibc-compat)"
  1475. help
  1476. Answer Y to support a glibc extension to allow passing
  1477. additional 'x' flag in the mode string for fopen() to specify that
  1478. the file should be open()ed with the O_EXCL flag set.
  1479. Most people will answer N.
  1480. config UCLIBC_HAS_FOPEN_CLOSEEXEC_MODE
  1481. bool "Support an fopen() 'e' flag for close-on-exec mode (glibc-compat)"
  1482. help
  1483. Answer Y to support a glibc extension to allow passing
  1484. additional 'e' flag in the mode string for fopen() to specify that
  1485. the file should be open()ed with the O_CLOEXEC flag set.
  1486. Most people will answer N.
  1487. config UCLIBC_HAS_GLIBC_CUSTOM_STREAMS
  1488. bool "Support fmemopen(), open_memstream(), and fopencookie() (glibc-compat)"
  1489. help
  1490. Answer Y to support the glibc 'custom stream' extension functions
  1491. fmemopen(), open_memstream(), and fopencookie().
  1492. NOTE: There are some minor differences regarding seeking behavior.
  1493. Most people will answer N.
  1494. config UCLIBC_HAS_PRINTF_M_SPEC
  1495. bool "Support the '%m' specifier in printf format strings (glibc-compat)"
  1496. help
  1497. Answer Y to support a glibc extension to interpret '%m' in printf
  1498. format strings as an instruction to output the error message string
  1499. (as generated by strerror) corresponding to the current value of
  1500. 'errno'.
  1501. Most people will answer N.
  1502. config UCLIBC_HAS_ERRNO_MESSAGES
  1503. bool "Include the errno message text in the library"
  1504. default y
  1505. help
  1506. Answer Y if you want to include the errno message text in the
  1507. library. This adds about 3K to the library, but enables strerror()
  1508. to generate text other than 'Unknown error <number>'.
  1509. Most people will answer Y.
  1510. config UCLIBC_HAS_SYS_ERRLIST
  1511. bool "Support sys_errlist[] (obsolete-compat)"
  1512. depends on UCLIBC_HAS_ERRNO_MESSAGES
  1513. help
  1514. Answer Y if you want to support the obsolete sys_errlist[].
  1515. This adds about 0.5k to the library, except for the mips
  1516. arch where it adds over 4K.
  1517. WARNING! In the future, support for sys_errlist[] may be unavailable
  1518. in at least some configurations. In fact, it may be removed
  1519. altogether.
  1520. Most people will answer N.
  1521. Application writers: use the strerror(3) function.
  1522. config UCLIBC_HAS_SIGNUM_MESSAGES
  1523. bool "Include the signum message text in the library"
  1524. default y
  1525. help
  1526. Answer Y if you want to include the signum message text in the
  1527. library. This adds about 0.5K to the library, but enables strsignal()
  1528. to generate text other than 'Unknown signal <number>'.
  1529. Most people will answer Y.
  1530. config UCLIBC_HAS_SYS_SIGLIST
  1531. bool "Support sys_siglist[] (bsd-compat)"
  1532. depends on UCLIBC_HAS_SIGNUM_MESSAGES
  1533. help
  1534. Answer Y if you want to support sys_siglist[].
  1535. WARNING! In the future, support for sys_siglist[] may be unavailable
  1536. in at least some configurations. In fact, it may be removed
  1537. altogether.
  1538. Most people will answer N.
  1539. config UCLIBC_HAS_GNU_GETOPT
  1540. bool "Support gnu getopt"
  1541. default y
  1542. help
  1543. Answer Y if you want to include full gnu getopt() instead of a
  1544. (much smaller) SUSv3 compatible getopt().
  1545. Note that getopt_long, getopt_long_only as well as getsubopt
  1546. are implemented on top of this choice.
  1547. Most people will answer Y.
  1548. config UCLIBC_HAS_GETOPT_LONG
  1549. bool "Support getopt_long/getopt_long_only (glibc-compat)"
  1550. default y
  1551. help
  1552. Answer Y if you want to include getopt_long[_only()] used by many
  1553. apps.
  1554. Most people will answer Y.
  1555. config UCLIBC_HAS_GNU_GETSUBOPT
  1556. bool "Support getsubopt"
  1557. default y
  1558. help
  1559. Answer Y if you want to include getsubopt().
  1560. Most people will answer Y.
  1561. config UCLIBC_HAS_ARGP
  1562. bool "Support argp"
  1563. select UCLIBC_HAS_GETOPT_LONG
  1564. select UCLIBC_HAS_GNU_GETOPT
  1565. select UCLIBC_HAS_WCHAR
  1566. default n
  1567. help
  1568. Argp is an interface for parsing unix-style argument vectors. Unlike
  1569. the common getopt interface, it provides many advanced features in
  1570. addition to parsing options, such as automatic output in response to
  1571. `--help' and `--version' options.
  1572. A library can export an argp option parser, which programs can easily
  1573. use in conjunction with their own option parser.
  1574. Argp support is needed by elfutils libdw.
  1575. Most people can safely answer N.
  1576. endmenu
  1577. menu "Big and Tall"
  1578. config UCLIBC_HAS_REGEX
  1579. bool "Regular Expression Support"
  1580. default y
  1581. help
  1582. POSIX regular expression code is really big -- 53k all by itself.
  1583. If you don't use regular expressions, turn this off and save space.
  1584. Of course, if you only statically link, leave this on, since it will
  1585. only be included in your apps if you use regular expressions.
  1586. config UCLIBC_HAS_FNMATCH
  1587. bool "fnmatch Support"
  1588. default y
  1589. help
  1590. POSIX fnmatch.
  1591. config UCLIBC_HAS_WORDEXP
  1592. bool "Support the wordexp() interface"
  1593. depends on UCLIBC_HAS_GLOB
  1594. help
  1595. The SuSv3 wordexp() interface performs word expansions per the Shell
  1596. and Utilities volume of IEEE Std 1003.1-2001, Section 2.6. It is
  1597. intended for use by applications that want to implement all of the
  1598. standard Bourne shell expansions on input data.
  1599. This interface is rarely used, and very large. Unless you have a
  1600. pressing need for wordexp(), you should probably answer N.
  1601. config UCLIBC_HAS_NFTW
  1602. bool "Support the nftw() interface"
  1603. help
  1604. The SuSv3 nftw() interface is used to recursively descend
  1605. directory paths while repeatedly calling a function.
  1606. This interface is rarely used, and adds around 4.5k. Unless you have
  1607. a pressing need for nftw(), you should probably answer N.
  1608. config UCLIBC_HAS_FTW
  1609. bool "Support the ftw() interface (SUSv4-obsolete)"
  1610. depends on UCLIBC_SUSV4_LEGACY
  1611. help
  1612. The SuSv3 ftw() interface is used to recursively descend
  1613. directory paths while repeatedly calling a function.
  1614. This interface is rarely used, and adds around 4.5k. Unless you have
  1615. a pressing need for ftw(), you should probably answer N.
  1616. config UCLIBC_HAS_FTS
  1617. bool "Support the fts() interface (bsd-compat)"
  1618. help
  1619. The fts functions are provided for traversing UNIX file hierarchies.
  1620. This interface is currently used by the elfutils and adds
  1621. around 7.5k.
  1622. You should port your application to use the POSIX nftw()
  1623. interface.
  1624. Unless you need to build/use elfutils, you should prolly answer N.
  1625. config UCLIBC_HAS_GLOB
  1626. bool "Support the glob() interface"
  1627. depends on UCLIBC_HAS_FNMATCH
  1628. default y
  1629. help
  1630. The glob interface is somewhat large (weighing in at about 2,5k). It
  1631. is used fairly often, but is an option since people wanting to go for
  1632. absolute minimum size may wish to omit it.
  1633. Most people will answer Y.
  1634. config UCLIBC_HAS_GNU_GLOB
  1635. bool "Support gnu glob() interface"
  1636. depends on UCLIBC_HAS_GLOB
  1637. help
  1638. The gnu glob interface is somewhat larger (weighing in at about 4,2k)
  1639. than it's SuSv3 counterpart (and is out of date). It is an old copy
  1640. from glibc and does not support all the GNU specific options.
  1641. Answer Y if you want to include full gnu glob() instead of the smaller
  1642. SUSv3 compatible glob().
  1643. Most people will answer N.
  1644. endmenu
  1645. menu "Library Installation Options"
  1646. config RUNTIME_PREFIX
  1647. string "uClibc runtime library directory"
  1648. default "/usr/$(TARGET_ARCH)-linux-uclibc/"
  1649. help
  1650. RUNTIME_PREFIX is the directory into which the uClibc runtime
  1651. libraries will be installed. The result will look something
  1652. like the following:
  1653. $(RUNTIME_PREFIX)/
  1654. lib/ <contains all runtime libraries>
  1655. usr/bin/ldd <the ldd utility program>
  1656. sbin/ldconfig <the ldconfig utility program>
  1657. This value is used by the 'make install' Makefile target. Since this
  1658. directory is compiled into the shared library loader, you will need to
  1659. recompile uClibc if you change this value...
  1660. For a typical target system this should be set to "/", such that
  1661. 'make install' will install /lib/libuClibc-<VERSION>.so
  1662. config DEVEL_PREFIX
  1663. string "uClibc development environment directory"
  1664. default "/usr/$(TARGET_ARCH)-linux-uclibc/usr/"
  1665. help
  1666. DEVEL_PREFIX is the directory into which the uClibc development
  1667. environment will be installed. The result will look something
  1668. like the following:
  1669. $(DEVEL_PREFIX)/
  1670. lib/ <contains static libs>
  1671. include/ <Where all the header files go>
  1672. This value is used by the 'make install' Makefile target when
  1673. installing a uClibc development environment.
  1674. For a typical target system this should be set to "/usr", such that
  1675. 'make install' will install /usr/include/<header files>.
  1676. config MULTILIB_DIR
  1677. string "library path component"
  1678. default "lib"
  1679. help
  1680. Path component where libraries reside.
  1681. For a typical target system this should be set to "lib", such that
  1682. 'make install' will install libraries to "/lib" and "/usr/lib"
  1683. respectively
  1684. DEVEL_PREFIX/MULTILIB_DIR
  1685. RUNTIME_PREFIX/MULTILIB_DIR
  1686. Other settings may include "lib32" or "lib64".
  1687. config HARDWIRED_ABSPATH
  1688. bool "Hardwire absolute paths into linker scripts"
  1689. default y
  1690. help
  1691. This prepends absolute paths to the libraries mentioned in linker
  1692. scripts such as libc.so.
  1693. This is a build time optimization. It has no impact on dynamic
  1694. linking at runtime, which doesn't use linker scripts.
  1695. You must disable this to use uClibc with old non-sysroot toolchains,
  1696. such as the prebuilt binary cross compilers at:
  1697. http://uclibc.org/downloads/binaries
  1698. The amount of time saved by this optimization is actually too small to
  1699. measure. The linker just had to search the library path to find the
  1700. linker script, so the dentries are cache hot if it has to search the
  1701. same path again. But it's what glibc does, so we do it too.
  1702. endmenu
  1703. menu "Security options"
  1704. config UCLIBC_BUILD_PIE
  1705. bool "Build utilities as ET_DYN/PIE executables"
  1706. depends on HAVE_SHARED
  1707. depends on TARGET_arm || TARGET_frv || TARGET_i386 || TARGET_mips || TARGET_powerpc || TARGET_nds32
  1708. select FORCE_SHAREABLE_TEXT_SEGMENTS
  1709. help
  1710. If you answer Y here, ldd and iconv are built as ET_DYN/PIE
  1711. executables.
  1712. It requires gcc-3.4 and binutils-2.15 (for arm 2.16) or later.
  1713. More about ET_DYN/PIE binaries on <http://pax.grsecurity.net/> .
  1714. WARNING: This option also enables FORCE_SHAREABLE_TEXT_SEGMENTS, so
  1715. all libraries have to be built with -fPIC or -fpic, and all
  1716. assembler functions must be written as position independent
  1717. code (PIC).
  1718. config HAVE_NO_SSP
  1719. bool
  1720. config UCLIBC_HAS_SSP
  1721. bool "Support for GCC stack smashing protector"
  1722. depends on !HAVE_NO_SSP
  1723. help
  1724. Add code to support GCC's -fstack-protector[-all] option to uClibc.
  1725. This requires GCC 4.1 or newer. GCC does not have to provide libssp,
  1726. the needed functions are added to ldso/libc instead.
  1727. GCC's stack protector is a reimplementation of IBM's propolice.
  1728. See http://www.trl.ibm.com/projects/security/ssp/ and
  1729. http://www.linuxfromscratch.org/hints/downloads/files/ssp.txt
  1730. for details.
  1731. Note that NOEXECSTACK on a kernel with address space randomization
  1732. is generally sufficient to prevent most buffer overflow exploits
  1733. without increasing code size. This option essentially adds debugging
  1734. code to catch them.
  1735. Most people will answer N.
  1736. config SSP_QUICK_CANARY
  1737. bool "Use simple guard values without accessing /dev/urandom"
  1738. depends on UCLIBC_HAS_SSP
  1739. help
  1740. Use gettimeofday(2) to define the __guard without accessing
  1741. /dev/urandom.
  1742. WARNING: This makes smashing stack protector vulnerable to timing
  1743. attacks.
  1744. Most people will answer N.
  1745. choice
  1746. prompt "Propolice protection blocking signal"
  1747. depends on UCLIBC_HAS_SSP
  1748. depends on DODEBUG
  1749. default PROPOLICE_BLOCK_SEGV
  1750. help
  1751. "abort" use SIGABRT to block offending programs.
  1752. This is the default implementation.
  1753. "segfault" use SIGSEGV to block offending programs.
  1754. Use this for debugging.
  1755. If unsure, answer "abort".
  1756. config PROPOLICE_BLOCK_ABRT
  1757. bool "abort"
  1758. config PROPOLICE_BLOCK_SEGV
  1759. bool "segfault"
  1760. endchoice
  1761. config UCLIBC_BUILD_SSP
  1762. bool "Build uClibc with -fstack-protector"
  1763. depends on UCLIBC_HAS_SSP
  1764. help
  1765. Build all uClibc libraries and executables with -fstack-protector,
  1766. adding extra stack overflow checking to most uClibc functions.
  1767. config UCLIBC_BUILD_RELRO
  1768. bool "Build uClibc with linker option -z RELRO"
  1769. depends on HAVE_SHARED
  1770. default y
  1771. help
  1772. Build all libraries and executables with "ld -z relro".
  1773. This tells the linker to mark chunks of an executable or shared
  1774. library read-only after applying dynamic relocations. (This comes
  1775. up when a global const variable is initialized to the address of a
  1776. function or the value of another global variable.)
  1777. This is a fairly obscure option the ld man page doesn't even bother
  1778. to document properly. It's a security paranoia issue that's more
  1779. likely to consume memory (by allocating an extra page) rather than
  1780. save it.
  1781. This is explained in more depth at
  1782. http://www.airs.com/blog/archives/189
  1783. Nobody is likely to care whether you say Y or N here.
  1784. config UCLIBC_BUILD_NOW
  1785. bool "Build uClibc with linker option -z NOW"
  1786. depends on HAVE_SHARED
  1787. help
  1788. Build all libraries and executables with "ld -z now".
  1789. This tells the linker to resolve all symbols when the library is
  1790. first loaded, rather than when each function is first called. This
  1791. increases start-up latency by a few microseconds and may do
  1792. unnecessary work (resolving symbols that are never used), but the
  1793. realtime people like it for making microbenchmark timings slightly
  1794. more predictable and in some cases it can be slightly faster due to
  1795. CPU cache behavior (not having to fault the linker back in to do
  1796. lazy symbol resolution).
  1797. Most people can't tell the difference between selecting Y or N here.
  1798. config UCLIBC_BUILD_NOEXECSTACK
  1799. bool "Build uClibc with noexecstack marking"
  1800. default y
  1801. help
  1802. Mark all assembler files as noexecstack, which will mark uClibc
  1803. as not requiring an executable stack. (This doesn't prevent other
  1804. files you link against from claiming to need an executable stack, it
  1805. just won't cause uClibc to request it unnecessarily.)
  1806. This is a security thing to make buffer overflows harder to exploit.
  1807. By itself, it's kind of useless, as Linus Torvalds explained in 1998:
  1808. http://old.lwn.net/1998/0806/a/linus-noexec.html
  1809. It only actually provides any security when combined with address
  1810. space randomization, explained here: http://lwn.net/Articles/121845/
  1811. Address space randomization is on by default in current linux
  1812. kernels (although it can be disabled using the option
  1813. CONFIG_COMPAT_BRK).
  1814. You should probably say Y.
  1815. endmenu
  1816. menu "Development/debugging options"
  1817. config CROSS_COMPILER_PREFIX
  1818. string "Cross-compiling toolchain prefix"
  1819. default ""
  1820. help
  1821. The prefix used to execute your cross-compiling toolchain. For
  1822. example, if you run 'arm-linux-uclibc-gcc' to compile something,
  1823. then enter 'arm-linux-uclibc-' here.
  1824. config UCLIBC_EXTRA_CFLAGS
  1825. string "Extra CFLAGS"
  1826. default ""
  1827. help
  1828. Add any additional CFLAGS to be used to build uClibc.
  1829. config DODEBUG
  1830. bool "Enable debugging symbols"
  1831. select EXTRA_WARNINGS
  1832. help
  1833. Say Y here if you wish to compile uClibc with debugging symbols.
  1834. This will allow you to use a debugger to examine uClibc internals
  1835. while applications are running. This increases the size of the
  1836. library considerably and should only be used when doing development.
  1837. If you are doing development and want to debug uClibc, answer Y.
  1838. Otherwise, answer N.
  1839. config DODEBUG_PT
  1840. bool "Build pthread with debugging output"
  1841. depends on UCLIBC_HAS_THREADS && UCLIBC_HAS_LINUXTHREADS
  1842. help
  1843. Enable debug output in libpthread. This is only useful when doing
  1844. development in libpthread itself.
  1845. Otherwise, answer N.
  1846. config DOSTRIP
  1847. bool "Strip libraries and executables"
  1848. default y
  1849. depends on !DODEBUG
  1850. help
  1851. Say Y here if you do wish to strip all uClibc libraries and
  1852. executables. No stripping increases the size of the binaries
  1853. considerably, but makes it possible to debug uClibc libraries.
  1854. Most people will answer Y.
  1855. config DOASSERTS
  1856. bool "Build with run-time assertion testing"
  1857. help
  1858. Say Y here to include runtime assertion tests.
  1859. This enables runtime assertion testing in some code, which can
  1860. increase the size of the library and incur runtime overhead.
  1861. If you say N, then this testing will be disabled.
  1862. config SUPPORT_LD_DEBUG
  1863. bool "Build the shared library loader with debugging support"
  1864. depends on HAVE_SHARED
  1865. help
  1866. Answer Y here to enable all the extra code needed to debug the uClibc
  1867. native shared library loader. The level of debugging noise that is
  1868. generated depends on the LD_DEBUG environment variable... Just set
  1869. LD_DEBUG to something like: 'LD_DEBUG=token1,token2,.. prog' to
  1870. debug your application. Diagnostic messages will then be printed to
  1871. the stderr.
  1872. For now these debugging tokens are available:
  1873. detail provide more information for some options
  1874. move display copy processing
  1875. symbols display symbol table processing
  1876. reloc display relocation processing; detail shows the
  1877. relocation patch
  1878. nofixups never fixes up jump relocations
  1879. bindings displays the resolve processing (function calls);
  1880. detail shows the relocation patch
  1881. all Enable everything!
  1882. The additional environment variable:
  1883. LD_DEBUG_OUTPUT=file
  1884. redirects the diagnostics to an output file created using
  1885. the specified name and the process id as a suffix.
  1886. An excellent start is simply:
  1887. $ LD_DEBUG=binding,move,symbols,reloc,detail ./appname
  1888. or to log everything to a file named 'logfile', try this
  1889. $ LD_DEBUG=all LD_DEBUG_OUTPUT=logfile ./appname
  1890. If you are doing development and want to debug uClibc's shared library
  1891. loader, answer Y. Mere mortals answer N.
  1892. config SUPPORT_LD_DEBUG_EARLY
  1893. bool "Build the shared library loader with early debugging support"
  1894. depends on HAVE_SHARED
  1895. help
  1896. Answer Y here to if you find the uClibc shared library loader is
  1897. crashing or otherwise not working very early on. This is typical
  1898. only when starting a new port when you haven't figured out how to
  1899. properly get the values for argc, argv, environ, etc. This method
  1900. allows a degree of visibility into the very early shared library
  1901. loader initialization process. If you are doing development and want
  1902. to debug the uClibc shared library loader early initialization,
  1903. answer Y. Mere mortals answer N.
  1904. config UCLIBC_MALLOC_DEBUGGING
  1905. bool "Build malloc with debugging support"
  1906. depends on MALLOC || MALLOC_STANDARD
  1907. select DOASSERTS
  1908. help
  1909. Answer Y here to compile extra debugging support code into malloc.
  1910. Malloc debugging output may then be enabled at runtime using the
  1911. MALLOC_DEBUG environment variable.
  1912. The value of MALLOC_DEBUG should be an integer, which is interpreted
  1913. as a bitmask with the following bits:
  1914. 1 - do extra consistency checking
  1915. 2 - output messages for malloc/free calls and OS
  1916. allocation calls
  1917. 4 - output messages for the `MMB' layer
  1918. 8 - output messages for internal malloc heap manipulation
  1919. calls
  1920. Because this increases the size of malloc appreciably (due to strings
  1921. etc), you should say N unless you need to debug a malloc problem.
  1922. config UCLIBC_HAS_BACKTRACE
  1923. bool "Add support for application self-debugging"
  1924. depends on HAVE_SHARED
  1925. help
  1926. Answer Y here to compile support for application self-debugging that
  1927. provides the following new functions:
  1928. backtrace, backtrace_symbols, backtrace_symbols_fd
  1929. The backtrace functionality is currently supported on some platforms, and it
  1930. based on dwarf2 informations to properly work, so any application that
  1931. want to use backtrace needs to be built with -fexceptions flag.
  1932. The symbol names may be unavailable without the use of special linker
  1933. options. For systems using the GNU linker, it is necessary to use the
  1934. -rdynamic linker option too. Note that names of "static" functions are not
  1935. exposed, and won't be available in the backtrace.
  1936. config WARNINGS
  1937. string "Compiler Warnings"
  1938. default "-Wall"
  1939. help
  1940. Set this to the set of compiler warnings you wish to see while compiling.
  1941. config EXTRA_WARNINGS
  1942. bool "Enable extra annoying warnings"
  1943. help
  1944. If you wish to build with extra warnings enabled, say Y here.
  1945. endmenu