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