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