Config.in 73 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336337338339340341342343344345346347348349350351352353354355356357358359360361362363364365366367368369370371372373374375376377378379380381382383384385386387388389390391392393394395396397398399400401402403404405406407408409410411412413414415416417418419420421422423424425426427428429430431432433434435436437438439440441442443444445446447448449450451452453454455456457458459460461462463464465466467468469470471472473474475476477478479480481482483484485486487488489490491492493494495496497498499500501502503504505506507508509510511512513514515516517518519520521522523524525526527528529530531532533534535536537538539540541542543544545546547548549550551552553554555556557558559560561562563564565566567568569570571572573574575576577578579580581582583584585586587588589590591592593594595596597598599600601602603604605606607608609610611612613614615616617618619620621622623624625626627628629630631632633634635636637638639640641642643644645646647648649650651652653654655656657658659660661662663664665666667668669670671672673674675676677678679680681682683684685686687688689690691692693694695696697698699700701702703704705706707708709710711712713714715716717718719720721722723724725726727728729730731732733734735736737738739740741742743744745746747748749750751752753754755756757758759760761762763764765766767768769770771772773774775776777778779780781782783784785786787788789790791792793794795796797798799800801802803804805806807808809810811812813814815816817818819820821822823824825826827828829830831832833834835836837838839840841842843844845846847848849850851852853854855856857858859860861862863864865866867868869870871872873874875876877878879880881882883884885886887888889890891892893894895896897898899900901902903904905906907908909910911912913914915916917918919920921922923924925926927928929930931932933934935936937938939940941942943944945946947948949950951952953954955956957958959960961962963964965966967968969970971972973974975976977978979980981982983984985986987988989990991992993994995996997998999100010011002100310041005100610071008100910101011101210131014101510161017101810191020102110221023102410251026102710281029103010311032103310341035103610371038103910401041104210431044104510461047104810491050105110521053105410551056105710581059106010611062106310641065106610671068106910701071107210731074107510761077107810791080108110821083108410851086108710881089109010911092109310941095109610971098109911001101110211031104110511061107110811091110111111121113111411151116111711181119112011211122112311241125112611271128112911301131113211331134113511361137113811391140114111421143114411451146114711481149115011511152115311541155115611571158115911601161116211631164116511661167116811691170117111721173117411751176117711781179118011811182118311841185118611871188118911901191119211931194119511961197119811991200120112021203120412051206120712081209121012111212121312141215121612171218121912201221122212231224122512261227122812291230123112321233123412351236123712381239124012411242124312441245124612471248124912501251125212531254125512561257125812591260126112621263126412651266126712681269127012711272127312741275127612771278127912801281128212831284128512861287128812891290129112921293129412951296129712981299130013011302130313041305130613071308130913101311131213131314131513161317131813191320132113221323132413251326132713281329133013311332133313341335133613371338133913401341134213431344134513461347134813491350135113521353135413551356135713581359136013611362136313641365136613671368136913701371137213731374137513761377137813791380138113821383138413851386138713881389139013911392139313941395139613971398139914001401140214031404140514061407140814091410141114121413141414151416141714181419142014211422142314241425142614271428142914301431143214331434143514361437143814391440144114421443144414451446144714481449145014511452145314541455145614571458145914601461146214631464146514661467146814691470147114721473147414751476147714781479148014811482148314841485148614871488148914901491149214931494149514961497149814991500150115021503150415051506150715081509151015111512151315141515151615171518151915201521152215231524152515261527152815291530153115321533153415351536153715381539154015411542154315441545154615471548154915501551155215531554155515561557155815591560156115621563156415651566156715681569157015711572157315741575157615771578157915801581158215831584158515861587158815891590159115921593159415951596159715981599160016011602160316041605160616071608160916101611161216131614161516161617161816191620162116221623162416251626162716281629163016311632163316341635163616371638163916401641164216431644164516461647164816491650165116521653165416551656165716581659166016611662166316641665166616671668166916701671167216731674167516761677167816791680168116821683168416851686168716881689169016911692169316941695169616971698169917001701170217031704170517061707170817091710171117121713171417151716171717181719172017211722172317241725172617271728172917301731173217331734173517361737173817391740174117421743174417451746174717481749175017511752175317541755175617571758175917601761176217631764176517661767176817691770177117721773177417751776177717781779178017811782178317841785178617871788178917901791179217931794179517961797179817991800180118021803180418051806180718081809181018111812181318141815181618171818181918201821182218231824182518261827182818291830183118321833183418351836183718381839184018411842184318441845184618471848184918501851185218531854185518561857185818591860186118621863186418651866186718681869187018711872187318741875187618771878187918801881188218831884188518861887188818891890189118921893189418951896189718981899190019011902190319041905190619071908190919101911191219131914191519161917191819191920192119221923192419251926192719281929193019311932193319341935193619371938193919401941194219431944194519461947194819491950195119521953195419551956195719581959196019611962196319641965196619671968196919701971197219731974197519761977197819791980198119821983198419851986198719881989199019911992199319941995199619971998199920002001200220032004200520062007200820092010201120122013201420152016201720182019202020212022202320242025202620272028202920302031203220332034203520362037203820392040204120422043204420452046204720482049205020512052205320542055205620572058205920602061206220632064206520662067206820692070207120722073207420752076207720782079208020812082208320842085208620872088208920902091209220932094209520962097209820992100210121022103210421052106210721082109211021112112211321142115211621172118211921202121212221232124212521262127212821292130213121322133213421352136213721382139214021412142214321442145214621472148214921502151215221532154215521562157215821592160216121622163216421652166216721682169217021712172217321742175217621772178217921802181218221832184218521862187218821892190219121922193219421952196219721982199220022012202220322042205220622072208220922102211221222132214221522162217221822192220222122222223222422252226222722282229223022312232223322342235223622372238223922402241224222432244224522462247224822492250225122522253225422552256225722582259226022612262226322642265226622672268226922702271227222732274227522762277227822792280228122822283228422852286228722882289229022912292229322942295229622972298229923002301230223032304230523062307230823092310231123122313231423152316231723182319232023212322232323242325232623272328232923302331233223332334233523362337233823392340234123422343234423452346234723482349235023512352235323542355235623572358235923602361236223632364236523662367236823692370237123722373237423752376237723782379238023812382238323842385238623872388238923902391239223932394239523962397239823992400240124022403240424052406240724082409241024112412241324142415241624172418241924202421242224232424242524262427
  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_riscv32 if DESIRED_TARGET_ARCH = "riscv32"
  39. default TARGET_sh if DESIRED_TARGET_ARCH = "sh"
  40. default TARGET_sparc if DESIRED_TARGET_ARCH = "sparc"
  41. default TARGET_sparc64 if DESIRED_TARGET_ARCH = "sparc64"
  42. default TARGET_tile if DESIRED_TARGET_ARCH = "tile"
  43. default TARGET_x86_64 if DESIRED_TARGET_ARCH = "x86_64"
  44. default TARGET_xtensa if DESIRED_TARGET_ARCH = "xtensa"
  45. help
  46. The architecture of your target.
  47. config TARGET_aarch64
  48. bool "aarch64"
  49. config TARGET_alpha
  50. bool "alpha"
  51. config TARGET_arc
  52. bool "arc"
  53. config TARGET_arm
  54. bool "arm"
  55. config TARGET_avr32
  56. bool "avr32"
  57. config TARGET_bfin
  58. bool "bfin"
  59. # someone could sync this tree:
  60. # http://linux-c6x.org/git/?p=uClibc.git;a=summary
  61. config TARGET_c6x
  62. bool "c6x"
  63. config TARGET_cris
  64. bool "cris"
  65. config TARGET_csky
  66. bool "csky"
  67. config TARGET_frv
  68. bool "frv"
  69. config TARGET_h8300
  70. bool "h8300"
  71. config TARGET_hppa
  72. bool "hppa"
  73. config TARGET_i386
  74. bool "i386"
  75. config TARGET_ia64
  76. bool "ia64"
  77. config TARGET_kvx
  78. bool "kvx"
  79. config TARGET_lm32
  80. bool "lm32"
  81. config TARGET_m68k
  82. bool "m68k"
  83. config TARGET_metag
  84. bool "metag"
  85. config TARGET_microblaze
  86. bool "microblaze"
  87. config TARGET_mips
  88. bool "mips"
  89. config TARGET_nds32
  90. bool "nds32"
  91. config TARGET_nios2
  92. bool "nios2"
  93. config TARGET_or1k
  94. bool "or1k"
  95. config TARGET_powerpc
  96. bool "powerpc"
  97. config TARGET_riscv64
  98. bool "riscv64"
  99. config TARGET_riscv32
  100. bool "riscv32"
  101. config TARGET_sh
  102. bool "superh"
  103. config TARGET_sparc
  104. bool "sparc"
  105. config TARGET_sparc64
  106. bool "sparc64"
  107. config TARGET_tile
  108. bool "tile"
  109. config TARGET_x86_64
  110. bool "x86_64"
  111. config TARGET_xtensa
  112. bool "xtensa"
  113. endchoice
  114. config TARGET_LDSO_NAME
  115. string
  116. default "ld64-uClibc" if TARGET_ia64
  117. default "ld64-uClibc" if TARGET_powerpc64
  118. default "ld64-uClibc" if TARGET_sparc64
  119. default "ld64-uClibc" if TARGET_x86_64
  120. default "ld64-uClibc" if TARGET_kvx
  121. default "ld64-uClibc" if CONFIG_MIPS_N64_ABI
  122. default "ld-uClibc"
  123. config TARGET_ARCH_BITS
  124. int
  125. default 64 if TARGET_aarch64
  126. default 64 if TARGET_ia64
  127. default 64 if TARGET_powerpc64
  128. default 64 if TARGET_sparc64
  129. default 64 if TARGET_x86_64
  130. default 64 if TARGET_kvx
  131. default 64 if CONFIG_MIPS_N64_ABI
  132. default 32
  133. menu "Target Architecture Features and Options"
  134. if TARGET_aarch64
  135. source "extra/Configs/Config.aarch64"
  136. endif
  137. if TARGET_alpha
  138. source "extra/Configs/Config.alpha"
  139. endif
  140. if TARGET_arm
  141. source "extra/Configs/Config.arm"
  142. endif
  143. if TARGET_avr32
  144. source "extra/Configs/Config.avr32"
  145. endif
  146. if TARGET_bfin
  147. source "extra/Configs/Config.bfin"
  148. endif
  149. if TARGET_cris
  150. source "extra/Configs/Config.cris"
  151. endif
  152. if TARGET_csky
  153. source "extra/Configs/Config.csky"
  154. endif
  155. if TARGET_frv
  156. source "extra/Configs/Config.frv"
  157. endif
  158. if TARGET_h8300
  159. source "extra/Configs/Config.h8300"
  160. endif
  161. if TARGET_hppa
  162. source "extra/Configs/Config.hppa"
  163. endif
  164. if TARGET_i386
  165. source "extra/Configs/Config.i386"
  166. endif
  167. if TARGET_ia64
  168. source "extra/Configs/Config.ia64"
  169. endif
  170. if TARGET_kvx
  171. source "extra/Configs/Config.kvx"
  172. endif
  173. if TARGET_lm32
  174. source "extra/Configs/Config.lm32"
  175. endif
  176. if TARGET_m68k
  177. source "extra/Configs/Config.m68k"
  178. endif
  179. if TARGET_metag
  180. source "extra/Configs/Config.metag"
  181. endif
  182. if TARGET_nds32
  183. source "extra/Configs/Config.nds32"
  184. endif
  185. if TARGET_nios2
  186. source "extra/Configs/Config.nios2"
  187. endif
  188. if TARGET_microblaze
  189. source "extra/Configs/Config.microblaze"
  190. endif
  191. if TARGET_mips
  192. source "extra/Configs/Config.mips"
  193. endif
  194. if TARGET_or1k
  195. source "extra/Configs/Config.or1k"
  196. endif
  197. if TARGET_powerpc
  198. source "extra/Configs/Config.powerpc"
  199. endif
  200. if TARGET_riscv64
  201. source "extra/Configs/Config.riscv64"
  202. endif
  203. if TARGET_riscv32
  204. source "extra/Configs/Config.riscv32"
  205. endif
  206. if TARGET_sh
  207. source "extra/Configs/Config.sh"
  208. endif
  209. if TARGET_sparc
  210. source "extra/Configs/Config.sparc"
  211. endif
  212. if TARGET_sparc64
  213. source "extra/Configs/Config.sparc64"
  214. endif
  215. if TARGET_tile
  216. source "extra/Configs/Config.tile"
  217. endif
  218. if TARGET_x86_64
  219. source "extra/Configs/Config.x86_64"
  220. endif
  221. if TARGET_xtensa
  222. source "extra/Configs/Config.xtensa"
  223. endif
  224. if TARGET_c6x
  225. source "extra/Configs/Config.c6x"
  226. endif
  227. if TARGET_arc
  228. source "extra/Configs/Config.arc"
  229. endif
  230. config TARGET_SUBARCH
  231. string
  232. default "e500" if CONFIG_E500
  233. default "classic" if CONFIG_CLASSIC
  234. default "sh4" if CONFIG_SH4
  235. default "sh4" if CONFIG_SH4A
  236. default "" if CONFIG_386
  237. default "i486" if CONFIG_486
  238. default "i586" if CONFIG_586
  239. default "i686" if CONFIG_686
  240. default ""
  241. source "extra/Configs/Config.in.arch"
  242. endmenu
  243. menu "General Library Settings"
  244. config HAVE_NO_PIC
  245. bool
  246. config DOPIC
  247. bool "Generate only Position Independent Code (PIC)"
  248. default y
  249. depends on !HAVE_NO_PIC
  250. help
  251. If you wish to build all of uClibc as PIC objects, then answer Y here.
  252. If you are unsure, then you should answer N.
  253. config STATIC_PIE
  254. bool "Add support for Static Position Independent Executables (PIE)"
  255. default n
  256. depends on DOPIC && !UCLIBC_FORMAT_FDPIC_ELF && \
  257. (TARGET_arm || TARGET_i386 || TARGET_x86_64 || TARGET_aarch64 || \
  258. TARGET_mips || TARGET_xtensa || TARGET_powerpc)
  259. config ARCH_HAS_NO_SHARED
  260. bool
  261. config ARCH_HAS_NO_LDSO
  262. bool
  263. select ARCH_HAS_NO_SHARED
  264. config ARCH_HAS_UCONTEXT
  265. bool
  266. config HAVE_SHARED
  267. bool "Enable shared libraries"
  268. depends on !ARCH_HAS_NO_SHARED
  269. default y
  270. help
  271. If you wish to build uClibc with support for shared libraries then
  272. answer Y here. If you only want to build uClibc as a static library,
  273. then answer N.
  274. config FORCE_SHAREABLE_TEXT_SEGMENTS
  275. bool "Only load shared libraries which can share their text segment"
  276. depends on HAVE_SHARED
  277. select DOPIC
  278. help
  279. If you answer Y here, the uClibc native shared library loader will
  280. only load shared libraries, which do not need to modify any
  281. non-writable segments. These libraries haven't set the DT_TEXTREL
  282. tag in the dynamic section (==> objdump).
  283. All your libraries must be compiled with -fPIC or -fpic, and all
  284. assembler function must be written as position independent code (PIC).
  285. Enabling this option will make uClibc's shared library loader a
  286. little bit smaller and guarantee that no memory will be wasted by
  287. badly coded shared libraries.
  288. config LDSO_LDD_SUPPORT
  289. bool "Native 'ldd' support"
  290. depends on HAVE_SHARED
  291. default y
  292. help
  293. Enable all the code needed to support traditional ldd,
  294. which executes the shared library loader to resolve all dependencies
  295. and then provide a list of shared libraries that are required for an
  296. application to function. Disabling this option will make uClibc's
  297. shared library loader a little bit smaller.
  298. Most people will answer Y.
  299. config LDSO_CACHE_SUPPORT
  300. bool "Enable library loader cache (ld.so.conf)"
  301. depends on HAVE_SHARED
  302. default y
  303. help
  304. Enable this to make use of /etc/ld.so.conf, the shared library loader
  305. cache configuration file to support for non-standard library paths.
  306. After updating this file, it is necessary to run 'ldconfig' to update
  307. the /etc/ld.so.cache shared library loader cache file.
  308. config LDSO_PRELOAD_ENV_SUPPORT
  309. bool "Enable library loader LD_PRELOAD environment"
  310. depends on HAVE_SHARED
  311. default y
  312. help
  313. Enable this to make use of LD_PRELOAD environment variable.
  314. A whitespace-separated list of additional, user-specified, ELF shared
  315. libraries to be loaded before all others. This can be used to
  316. selectively override functions in other shared libraries. For
  317. set-user-ID/set-group-ID ELF binaries, only libraries in the standard
  318. search directories that are also set-user-ID will be loaded.
  319. config LDSO_PRELOAD_FILE_SUPPORT
  320. bool "Enable library loader preload file (ld.so.preload)"
  321. depends on HAVE_SHARED
  322. help
  323. Enable this to make use of /etc/ld.so.preload. This file contains a
  324. whitespace separated list of shared libraries to be loaded before
  325. the program.
  326. config LDSO_BASE_FILENAME
  327. string "Shared library loader naming prefix"
  328. depends on HAVE_SHARED && (LDSO_CACHE_SUPPORT || LDSO_PRELOAD_FILE_SUPPORT)
  329. default "ld.so"
  330. help
  331. If you wish to support both uClibc and glibc on the same system, it
  332. is necessary to set this to something other than "ld.so" to avoid
  333. conflicts with glibc, which also uses "ld.so". This prevents both
  334. libraries from using the same /etc/ld.so.* files. If you wish to
  335. support both uClibc and glibc on the same system then you should set
  336. this to "ld-uClibc.so".
  337. Most people will leave this set to the default of "ld.so".
  338. WARNING: Changing the default prefix could cause problems with
  339. binutils' ld !
  340. config LDSO_STANDALONE_SUPPORT
  341. bool "Dynamic linker stand-alone mode support"
  342. depends on HAVE_SHARED
  343. help
  344. The dynamic linker can be run either indirectly through running some
  345. dynamically linked program or library (in which case no command line
  346. options to the dynamic linker can be passed and, in the ELF case, the
  347. dynamic linker which is stored in the .interp section of the program
  348. is executed) or directly by running:
  349. /lib/ld-uClibc.so.* [OPTIONS] [PROGRAM [ARGUMENTS]]
  350. Stand-alone execution is a prerequisite for adding prelink
  351. capabilities to uClibc dynamic linker, as well useful for testing an
  352. updated version of the dynamic linker without breaking the system.
  353. config LDSO_PRELINK_SUPPORT
  354. bool "Dynamic linker prelink support"
  355. depends on HAVE_SHARED
  356. select LDSO_STANDALONE_SUPPORT
  357. help
  358. The dynamic linker can be used in stand-alone mode by the prelink tool
  359. for prelinking ELF shared libraries and binaries to speed up startup
  360. time. It also is able to load and handle prelinked libraries and
  361. binaries at runtime.
  362. config ARCH_VDSO_SUPPORT
  363. bool
  364. config VDSO_SUPPORT
  365. bool "Dynamic linker vDSO support"
  366. depends on ARCH_VDSO_SUPPORT
  367. help
  368. Enable this option to support vDSO loading
  369. vDSO provides access to some kernel function without a systemcall
  370. if provided by the kernel
  371. most archs support gettimeofday() and clock_gettime()
  372. vDSO loading can be disabled via VDSO_DISABLE environment variable
  373. config UCLIBC_STATIC_LDCONFIG
  374. bool "Link ldconfig statically"
  375. depends on HAVE_SHARED
  376. default y
  377. help
  378. Enable this option to statically link the ldconfig binary.
  379. Making ldconfig static can be beneficial if you have a library
  380. problem and need to use ldconfig to recover. Sometimes it is
  381. preferable to instead keep the size of the system down, in which
  382. case you should disable this option.
  383. config LDSO_RUNPATH
  384. bool "Enable ELF RUNPATH tag support"
  385. depends on HAVE_SHARED
  386. default y if LDSO_CACHE_SUPPORT
  387. help
  388. ELF's may have dynamic RPATH/RUNPATH tags. These tags list paths
  389. which extend the library search paths. They are really only useful
  390. if a package installs libraries in non standard locations and
  391. ld.so.conf support is disabled.
  392. Usage of RUNPATH tags is not too common, so disabling this feature
  393. should be safe for most people.
  394. config LDSO_RUNPATH_OF_EXECUTABLE
  395. bool "Use executables RUNPATH/RPATH when searching for libraries."
  396. depends on LDSO_RUNPATH
  397. default n
  398. help
  399. Use the executables RUNPATH/RPATH to find to find libraries even
  400. though this behavour is not standard. Setting this option causes
  401. the uclibc dynamic linker behavour to match the glibc dynamic linker.
  402. config LDSO_SAFE_RUNPATH
  403. bool "Allow only RUNPATH beginning with /"
  404. depends on LDSO_RUNPATH
  405. default y
  406. help
  407. Allow only absolute path in RPATH/RUNPATH.
  408. config LDSO_SEARCH_INTERP_PATH
  409. bool "Add ldso path to lib search path"
  410. depends on HAVE_SHARED
  411. default y
  412. help
  413. The ldso is told where it is being executed from and can use that
  414. path to find related core libraries. This is useful by default,
  415. but can be annoying in a mixed development environment.
  416. i.e. if the ldso is run from /foo/boo/ldso.so, it will start its
  417. library search with /foo/boo/
  418. If unsure, simply say Y here.
  419. config LDSO_LD_LIBRARY_PATH
  420. bool "Add LD_LIBRARY_PATH to lib search path"
  421. depends on HAVE_SHARED
  422. default y
  423. help
  424. On hardened system it could be useful to disable the use of
  425. LD_LIBRARY_PATH environment variable (a colon-separated list of
  426. directories in which to search for ELF libraries at execution-time).
  427. If unsure, simply say Y here.
  428. config UCLIBC_CTOR_DTOR
  429. bool
  430. default y if !TARGET_riscv64 && !TARGET_lm32
  431. help
  432. If you wish to build uClibc with support for global constructor
  433. (ctor) and global destructor (dtor) support, then answer Y here.
  434. When ctor/dtor support is enabled, binaries linked with uClibc must
  435. also be linked with crtbegin.o and crtend.o which are provided by gcc
  436. (the "*startfile:" and "*endfile:" settings in your gcc specs file
  437. may need to be adjusted to include these files). This support will
  438. also add a small amount of additional size to each binary compiled vs
  439. uClibc. If you will be using uClibc with C++, or if you need the gcc
  440. __attribute__((constructor)) and __attribute__((destructor)) to work,
  441. then you definitely want to answer Y here. If you don't need ctors
  442. or dtors and want your binaries to be as small as possible, then
  443. answer N.
  444. config LDSO_GNU_HASH_SUPPORT
  445. bool "Enable GNU hash style support"
  446. depends on HAVE_SHARED && !TARGET_mips
  447. help
  448. Newest binutils support a new hash style named GNU-hash. The dynamic
  449. linker will use the new GNU-hash section (.gnu.hash) for symbol lookup
  450. if present into the ELF binaries, otherwise it will use the old SysV
  451. hash style (.hash). This ensures that it is completely backward
  452. compatible.
  453. Further, being the hash table implementation self-contained into each
  454. executable and shared libraries, objects with mixed hash style can
  455. peacefully coexist in the same process.
  456. If you want to use this new feature, answer Y
  457. choice
  458. prompt "Thread support"
  459. default HAS_NO_THREADS
  460. help
  461. If you want to compile uClibc with pthread support, then answer Y.
  462. This will increase the size of uClibc by adding a bunch of locking
  463. to critical data structures, and adding extra code to ensure that
  464. functions are properly reentrant.
  465. config HAS_NO_THREADS
  466. bool "none"
  467. help
  468. Disable thread support.
  469. config UCLIBC_HAS_LINUXTHREADS
  470. bool "Linuxthreads"
  471. # linuxthreads need nanosleep()
  472. select UCLIBC_HAS_REALTIME
  473. depends on !TARGET_aarch64 && \
  474. !TARGET_riscv64 && \
  475. !TARGET_riscv32 && \
  476. !TARGET_metag
  477. help
  478. If you want to compile uClibc with Linuxthreads support, then answer Y.
  479. config UCLIBC_HAS_THREADS_NATIVE
  480. bool "Native POSIX Threading (NPTL)"
  481. select UCLIBC_HAS_TLS
  482. select UCLIBC_HAS_STDIO_FUTEXES
  483. select UCLIBC_HAS_REALTIME
  484. # i386 has no lowlevellock support (yet) as opposed to i486 onward
  485. depends on !CONFIG_386 && \
  486. !TARGET_alpha && \
  487. !TARGET_avr32 && \
  488. !TARGET_bfin && \
  489. !TARGET_c6x && \
  490. !TARGET_cris && \
  491. !TARGET_frv && \
  492. !TARGET_h8300 && \
  493. !TARGET_hppa && \
  494. !TARGET_ia64 && \
  495. (ARCH_USE_MMU || TARGET_arm)
  496. help
  497. If you want to compile uClibc with NPTL support, then answer Y.
  498. endchoice
  499. config UCLIBC_HAS_THREADS
  500. def_bool y if !HAS_NO_THREADS
  501. config UCLIBC_HAS_TLS
  502. bool "Thread-Local Storage"
  503. depends on UCLIBC_HAS_THREADS_NATIVE
  504. help
  505. If you want to enable TLS support then answer Y.
  506. This is fast an efficient way to store per-thread local data
  507. which is not on stack. It needs __thread support enabled in
  508. gcc.
  509. config PTHREADS_DEBUG_SUPPORT
  510. bool "Build pthreads debugging support"
  511. depends on UCLIBC_HAS_THREADS
  512. help
  513. Say Y here if you wish to be able to debug applications that use
  514. uClibc's pthreads library. By enabling this option, a library
  515. named libthread_db will be built. This library will be dlopen()'d
  516. by gdb and will allow gdb to debug the threads in your application.
  517. IMPORTANT NOTE! Because gdb must dlopen() the libthread_db library,
  518. you must compile gdb with uClibc in order for pthread debugging to
  519. work properly.
  520. If you are doing development and want to debug applications using
  521. uClibc's pthread library, answer Y. Otherwise, answer N.
  522. config PTHREADS_STACK_DEFAULT_SIZE
  523. int "Default thread stack size"
  524. default 4194304 if TARGET_alpha # 4 MiB
  525. default 4194304 if TARGET_powerpc # 4 MiB
  526. default 2097152 # 2 MiB
  527. help
  528. Set the default thread stack size. This option is useful on MMU-less
  529. systems where the stack size is fixed and the default stack size may
  530. be excessively large and waste memory.
  531. config UCLIBC_HAS_SYSLOG
  532. bool "Syslog support"
  533. default y
  534. depends on UCLIBC_HAS_NETWORK_SUPPORT
  535. select UCLIBC_HAS_SOCKET
  536. help
  537. Support sending messages to the system logger.
  538. This requires socket-support.
  539. config UCLIBC_HAS_LFS
  540. def_bool y
  541. help
  542. Large file support (always enabled; config symbol retained for
  543. feature test to be compatible with uClibc).
  544. choice
  545. prompt "Malloc Implementation"
  546. default MALLOC if ! ARCH_USE_MMU
  547. default MALLOC_STANDARD if ARCH_USE_MMU
  548. config MALLOC
  549. bool "malloc"
  550. help
  551. "malloc" use mmap for all allocations and so works very well on
  552. MMU-less systems that do not support the brk() system call. It is
  553. pretty smart about reusing already allocated memory, and minimizing
  554. memory wastage.
  555. This is the default for uClinux MMU-less systems.
  556. config MALLOC_SIMPLE
  557. bool "malloc-simple"
  558. help
  559. "malloc-simple" is trivially simple and slow as molasses. It
  560. was written from scratch for uClibc, and is the simplest possible
  561. (and therefore smallest) malloc implementation.
  562. This uses only the mmap() system call to allocate and free memory,
  563. and does not use the brk() system call at all, making it a fine
  564. choice for MMU-less systems with very limited memory. It's 100%
  565. standards compliant, thread safe, very small, and releases freed
  566. memory back to the OS immediately rather than keeping it in the
  567. process's heap for reallocation. It is also VERY SLOW.
  568. config MALLOC_STANDARD
  569. bool "malloc-standard"
  570. depends on ARCH_USE_MMU
  571. help
  572. "malloc-standard" is derived from the public domain dlmalloc
  573. implementation by Doug Lea. It is quite fast, and is pretty smart
  574. about reusing already allocated memory, and minimizing memory
  575. wastage. This uses brk() for small allocations, while using mmap()
  576. for larger allocations. This is the default malloc implementation
  577. for uClibc.
  578. If unsure, answer "malloc-standard".
  579. endchoice
  580. config UCLIBC_DYNAMIC_ATEXIT
  581. bool "Dynamic atexit() Support"
  582. default y
  583. help
  584. When this option is enabled, uClibc will support an infinite number,
  585. of atexit() and on_exit() functions, limited only by your available
  586. memory. This can be important when uClibc is used with C++, since
  587. global destructors are implemented via atexit(), and it is quite
  588. possible to exceed the default number when this option is disabled.
  589. Enabling this option adds a few bytes, and more significantly makes
  590. atexit and on_exit depend on malloc, which can be bad when compiling
  591. static executables.
  592. Unless you use uClibc with C++, you should probably answer N.
  593. config UCLIBC_HAS_UTMPX
  594. bool "utmpx based support for tracking login/logouts to/from the system"
  595. help
  596. Answer y to enable support for accessing user accounting database.
  597. It can be used to track all login/logout to the system.
  598. config UCLIBC_HAS_UTMP
  599. bool "utmp support (XPG2 compat, SVr4 compat)"
  600. depends on UCLIBC_HAS_UTMPX
  601. help
  602. Answer y to enable legacy SVID support for accessing
  603. user accounting database:
  604. getutent(), getutid(), getutline(), pututline(),
  605. setutent(), endutent(), utmpname() in utmp.h
  606. It can be used to track all login/logout to the system.
  607. If unsure, answer N and use corresponding POSIX functions
  608. from utmpx.h
  609. config UCLIBC_SUSV2_LEGACY
  610. bool "Enable SuSv2 LEGACY functions"
  611. help
  612. Enable this option if you want to have SuSv2 LEGACY functions
  613. Currently applies to:
  614. valloc
  615. WARNING! ABI incompatibility.
  616. config UCLIBC_SUSV3_LEGACY
  617. bool "Enable SuSv3 LEGACY functions"
  618. #vfork,
  619. # h_errno
  620. # gethostbyaddr
  621. # gethostbyname
  622. help
  623. Enable this option if you want to have SuSv3 LEGACY functions
  624. in the library, else they are replaced by SuSv3 proposed macros.
  625. Currently applies to:
  626. bcmp, bcopy, bzero, index, rindex, ftime,
  627. bsd_signal, (ecvt), (fcvt), gcvt, (getcontext),
  628. (getwd), (makecontext),
  629. mktemp, (pthread_attr_getstackaddr), (pthread_attr_setstackaddr),
  630. scalb, (setcontext), (swapcontext), ualarm, usleep,
  631. wcswcs.
  632. WARNING! ABI incompatibility.
  633. config UCLIBC_HAS_CONTEXT_FUNCS
  634. bool "Use obsolescent context control functions"
  635. depends on UCLIBC_SUSV3_LEGACY && ARCH_HAS_UCONTEXT
  636. help
  637. Add into library the SuSv3 obsolescent functions used for context
  638. control. The setcontext family allows the implementation in C of
  639. advanced control flow patterns such as iterators, fibers, and
  640. coroutines. They may be viewed as an advanced version of
  641. setjmp/longjmp; whereas the latter allows only a single non-local jump
  642. up the stack, setcontext allows the creation of multiple cooperative
  643. threads of control, each with its own stack.
  644. These functions are: setcontext, getcontext, makecontext, swapcontext.
  645. config UCLIBC_SUSV3_LEGACY_MACROS
  646. bool "Enable SuSv3 LEGACY macros"
  647. help
  648. Enable this option if you want to have SuSv3 LEGACY macros.
  649. Currently applies to bcopy/bzero/bcmp/index/rindex et al.
  650. WARNING! ABI incompatibility.
  651. config UCLIBC_SUSV4_LEGACY
  652. bool "Enable SuSv4 LEGACY or obsolescent functions"
  653. help
  654. Enable this option if you want to have SuSv4 LEGACY functions
  655. and macros in the library.
  656. Currently applies to:
  657. - XSI functions:
  658. _longjmp, _setjmp, _tolower, _toupper, ftw, getitimer,
  659. gettimeofday, isascii, pthread_getconcurrency,
  660. pthread_setconcurrency, setitimer, setpgrp, sighold,
  661. sigignore, sigpause, sigrelse, sigset, siginterrupt,
  662. tempnam, toascii, ulimit.
  663. - Base functions:
  664. asctime, asctime_r, ctime, ctime_r, gets, rand_r,
  665. tmpnam, utime.
  666. WARNING! ABI incompatibility.
  667. config UCLIBC_STRICT_HEADERS
  668. bool "Hide structures and constants for unsupported features"
  669. help
  670. Hide structures and constants in headers that should not be used,
  671. because the respective feature is disabled.
  672. WARNING! enabling this option requires to patch many faulty apps,
  673. since they make (wrongly) use of these structures/constants,
  674. although the feature was disabled.
  675. config UCLIBC_HAS_STUBS
  676. bool "Provide stubs for unavailable functionality"
  677. help
  678. With this option uClibc provides non-functional stubs for
  679. functions which are impossible to implement on the target
  680. architecture. Otherwise, such functions are simply omitted.
  681. config UCLIBC_HAS_SHADOW
  682. bool "Shadow Password Support"
  683. default y
  684. help
  685. Answer N if you do not need shadow password support.
  686. Most people will answer Y.
  687. config UCLIBC_HAS_PROGRAM_INVOCATION_NAME
  688. bool "Support for program_invocation_name"
  689. help
  690. Support for the GNU-specific program_invocation_name and
  691. program_invocation_short_name strings. Some GNU packages
  692. (like tar and coreutils) utilize these for extra useful
  693. output, but in general are not required.
  694. At startup, these external strings are automatically set
  695. up based on the value of ARGV[0].
  696. If unsure, just answer N.
  697. config UCLIBC_HAS___PROGNAME
  698. bool "Support for __progname"
  699. default y
  700. help
  701. Some packages (like openssh) like to peek into internal libc
  702. symbols to make their output a bit more user friendly.
  703. At startup, __progname is automatically set up based on the
  704. value of ARGV[0].
  705. If unsure, just answer N.
  706. config UCLIBC_HAS_PTY
  707. bool "Support for pseudo-terminals"
  708. default y
  709. help
  710. This enables support for pseudo-terminals (see man 4 pts
  711. and man 7 pty).
  712. If unsure, just answer Y.
  713. config ASSUME_DEVPTS
  714. bool "Assume that /dev/pts is a devpts or devfs file system"
  715. default y
  716. depends on UCLIBC_HAS_PTY
  717. help
  718. Enable this if /dev/pts is on a devpts or devfs filesystem. Both
  719. these filesystems automatically manage permissions on the /dev/pts
  720. devices. You may need to mount your devpts or devfs filesystem on
  721. /dev/pts for this to work.
  722. Most people should answer Y.
  723. config UNIX98PTY_ONLY
  724. bool "Support only Unix 98 PTYs"
  725. default y
  726. depends on UCLIBC_HAS_PTY
  727. help
  728. If you want to support only Unix 98 PTYs enable this. Some older
  729. applications may need this disabled and will thus use legacy BSD
  730. style PTY handling which is more complex and also bigger than
  731. Unix 98 PTY handling.
  732. For most current programs, you can generally answer Y.
  733. if UNIX98PTY_ONLY
  734. config UCLIBC_HAS_GETPT
  735. bool "Support getpt() (glibc-compat)"
  736. depends on UCLIBC_HAS_PTY
  737. help
  738. Some packages may need getpt().
  739. All of those are non-standard and can be considered
  740. GNU/libc compatibility.
  741. Either use posix_openpt() or just open /dev/ptmx yourself.
  742. If unsure, just say N.
  743. endif
  744. if !UNIX98PTY_ONLY
  745. # Have to use __libc_ptyname{1,2}[] and related bloat
  746. config UCLIBC_HAS_GETPT
  747. def_bool y
  748. endif
  749. config UCLIBC_HAS_LIBUTIL
  750. bool "Provide libutil library and functions"
  751. depends on UCLIBC_HAS_PTY
  752. help
  753. Provide a libutil library.
  754. This non-standard conforming library provides the following
  755. utility functions:
  756. forkpty(): combines openpty(), fork(2), and login_tty() to
  757. create a new process operating in a pseudo-terminal.
  758. login(): write utmp and wtmp entries
  759. login_tty(): prepares for a login on the tty fd by creating a
  760. new session, making fd the controlling terminal for
  761. the calling process, setting fd to be the standard
  762. input, output, and error streams of the current
  763. process, and closing fd.
  764. logout(): write utmp and wtmp entries
  765. logwtmp(): constructs a utmp structure and calls updwtmp() to
  766. append the structure to the utmp file.
  767. openpty(): finds an available pseudo-terminal and returns
  768. file descriptors for the master and slave
  769. This library adds about 3k-4k to your system.
  770. config UCLIBC_HAS_TM_EXTENSIONS
  771. bool "Support 'struct tm' timezone extension fields"
  772. default y
  773. help
  774. Enabling this option adds fields to 'struct tm' in time.h for
  775. tracking the number of seconds east of UTC, and an abbreviation for
  776. the current timezone. These fields are not specified by the SuSv3
  777. standard, but they are commonly used in both GNU and BSD application
  778. code.
  779. To strictly follow the SuSv3 standard, leave this disabled.
  780. Most people will probably want to answer Y.
  781. config UCLIBC_HAS_TZ_CACHING
  782. bool "Enable caching of the last valid timezone 'TZ' string"
  783. default y
  784. help
  785. Answer Y to enable caching of the last valid 'TZ' string describing
  786. the timezone setting. This allows a quick string compare to avoid
  787. repeated parsing of unchanged 'TZ' strings when tzset() is called.
  788. Most people will answer Y.
  789. config UCLIBC_HAS_TZ_FILE
  790. bool "Enable '/etc/TZ' file support to set a default timezone (uClibc-specific)"
  791. default y
  792. help
  793. Answer Y to enable the setting of a default timezone for uClibc.
  794. Ordinarily, uClibc gets the timezone information exclusively from the
  795. 'TZ' environment variable. In particular, there is no support for
  796. the zoneinfo directory tree or the /etc/timezone file used by glibc.
  797. With this option enabled, uClibc will use the value stored in the
  798. file '/etc/TZ' (default path) to obtain timezone information if the
  799. 'TZ' environment variable is missing or has an invalid value. The
  800. file consists of a single line (newline required) of text describing
  801. the timezone in the format specified for the TZ environment variable.
  802. Doing 'echo CST6CDT > /etc/TZ' is enough to create a valid file.
  803. See
  804. http://www.opengroup.org/onlinepubs/007904975/basedefs/xbd_chap08.html
  805. for details on valid settings of 'TZ'.
  806. Most people will answer Y.
  807. config UCLIBC_HAS_TZ_FILE_READ_MANY
  808. bool "Repeatedly read the '/etc/TZ' file"
  809. depends on UCLIBC_HAS_TZ_FILE
  810. default y
  811. help
  812. Answer Y to enable repeated reading of the '/etc/TZ' file even after
  813. a valid value has been read. This incurs the overhead of an
  814. open/read/close for each tzset() call (explicit or implied). However,
  815. setting this will allow applications to update their timezone
  816. information if the contents of the file change.
  817. Most people will answer Y.
  818. config UCLIBC_TZ_FILE_PATH
  819. string "Path to the 'TZ' file for setting the global timezone"
  820. depends on UCLIBC_HAS_TZ_FILE
  821. default "/etc/TZ"
  822. help
  823. This is the path to the 'TZ' file.
  824. Most people will use the default of '/etc/TZ'.
  825. config UCLIBC_FALLBACK_TO_ETC_LOCALTIME
  826. bool "Use /etc/localtime as a fallback"
  827. depends on UCLIBC_HAS_TZ_FILE
  828. default y
  829. help
  830. Answer Y to try to use /etc/localtime file.
  831. On glibc systems this file (if it is in TZif2 format)
  832. contains timezone string at the end.
  833. Most people will answer Y.
  834. endmenu
  835. menu "Advanced Library Settings"
  836. config UCLIBC_PWD_BUFFER_SIZE
  837. int "Buffer size for getpwnam() and friends"
  838. default 256
  839. range 12 1024
  840. help
  841. This sets the value of the buffer size for getpwnam() and friends.
  842. By default, this is 256. (For reference, glibc uses 1024).
  843. The value can be found using sysconf() with the _SC_GETPW_R_SIZE_MAX
  844. parameter.
  845. config UCLIBC_GRP_BUFFER_SIZE
  846. int "Buffer size for getgrnam() and friends"
  847. default 256
  848. range 12 1024
  849. help
  850. This sets the value of the buffer size for getgrnam() and friends.
  851. By default, this is 256. (For reference, glibc uses 1024).
  852. The value can be found using sysconf() with the _SC_GETGR_R_SIZE_MAX
  853. parameter.
  854. comment "Support various families of functions"
  855. config UCLIBC_LINUX_SPECIFIC
  856. bool "Linux specific functions"
  857. default y
  858. help
  859. accept4(), bdflush(),
  860. capget(), capset(), eventfd(), fallocate(),
  861. fstatfs(), getrandom(), inotify_*(), ioperm(), iopl(),
  862. madvise(), modify_ldt(), pipe2(), personality(),
  863. prctl()/arch_prctl(), pivot_root(), modify_ldt(),
  864. ppoll(), readahead(), reboot(), remap_file_pages(),
  865. sched_getaffinity(), sched_setaffinity(), sendfile(),
  866. setfsgid(), setfsuid(), setresgid(), setresuid(),
  867. splice(), vmsplice(), tee(), signalfd(), statfs(),
  868. swapoff(), swapon(), sync_file_range(), syncfs(),
  869. _sysctl(), sysinfo(), timerfd_*(), vhangup(), umount(),
  870. umount2()
  871. config UCLIBC_HAS_GNU_ERROR
  872. bool "Support GNU extensions for error-reporting"
  873. default y
  874. help
  875. Support for the GNU-specific error(), error_at_line(),
  876. void (* error_print_progname)(), error_message_count
  877. functions and variables. Some GNU packages
  878. utilize these for extra useful output, but in general
  879. are not required.
  880. If unsure, just answer N.
  881. config UCLIBC_BSD_SPECIFIC
  882. bool "BSD specific functions"
  883. default y
  884. help
  885. mincore(), getdomainname(), setdomainname()
  886. If unsure, say N.
  887. config UCLIBC_HAS_BSD_ERR
  888. bool "BSD err functions"
  889. default y
  890. help
  891. These functions are non-standard BSD extensions.
  892. err(), errx(), warn(), warnx(), verr(), verrx(), vwarn(), vwarnx()
  893. If unsure, say N.
  894. config UCLIBC_HAS_OBSOLETE_BSD_SIGNAL
  895. bool "BSD obsolete signal functions"
  896. help
  897. These functions are provided as a compatibility interface for
  898. programs that make use of the historical System V signal API.
  899. This API is obsolete:
  900. new applications should use the POSIX signal API (sigaction(2),
  901. sigprocmask(2), etc.).
  902. Affected functions:
  903. sigset(), sighold(), sigrelse(), sigignore()
  904. If unsure, say N.
  905. config UCLIBC_HAS_BSD_B64_NTOP_B64_PTON
  906. bool "Support b64_ntop(), b64_pton() (bsd-compat)"
  907. help
  908. Answer Y if you need additional BSD compatibility
  909. (e.g. for openbsd-netcat).
  910. Most people will say N.
  911. config UCLIBC_HAS_OBSOLETE_SYSV_SIGNAL
  912. bool "SYSV obsolete signal functions"
  913. help
  914. Use of sysv_signal() should be avoided; use sigaction(2) instead.
  915. If unsure, say N.
  916. config UCLIBC_NTP_LEGACY
  917. bool "ntp_*() aliases"
  918. help
  919. Provide legacy aliases for ntp functions:
  920. ntp_adjtime(), ntp_gettime()
  921. It is safe to say N here.
  922. config UCLIBC_SV4_DEPRECATED
  923. bool "Enable SVr4 deprecated functions"
  924. help
  925. These functions are DEPRECATED in System V release 4.
  926. Say N unless you desparately need one of the functions below:
  927. ustat() [use statfs(2) in your code instead]
  928. config UCLIBC_HAS_REALTIME
  929. bool "Realtime-related family of SUSv functions"
  930. default y
  931. help
  932. These functions are part of the Timers option and need not
  933. be available on all implementations.
  934. Includes AIO, message-queue, scheduler, semaphore functions:
  935. aio.h
  936. mqueue.h
  937. sched.h
  938. semaphore.h
  939. aio_cancel()
  940. aio_error()
  941. aio_fsync()
  942. aio_read()
  943. lio_listio()
  944. aio_return()
  945. aio_suspend()
  946. aio_write()
  947. clock_getres(), clock_gettime(), clock_settime()
  948. fdatasync()
  949. mlockall(), munlockall()
  950. mlock(), munlock()
  951. mq_close()
  952. mq_getattr()
  953. mq_notify()
  954. mq_open()
  955. mq_receive()
  956. mq_send()
  957. mq_setattr()
  958. mq_unlink()
  959. nanosleep()
  960. sched_getparam()
  961. sched_get_priority_max(), sched_get_priority_min()
  962. sched_getscheduler()
  963. sched_rr_get_interval()
  964. sched_setparam()
  965. sched_setscheduler()
  966. sem_close()
  967. sem_destroy()
  968. sem_getvalue()
  969. sem_init()
  970. sem_open()
  971. sem_post()
  972. sem_trywait(), sem_wait()
  973. sem_unlink()
  974. sigqueue()
  975. sigtimedwait(), sigwaitinfo()
  976. timer_create()
  977. timer_delete()
  978. timer_getoverrun(), timer_gettime(), timer_settime()
  979. config UCLIBC_HAS_ADVANCED_REALTIME
  980. bool "Advanced realtime-related family of SUSv functions"
  981. default y
  982. depends on UCLIBC_HAS_REALTIME
  983. help
  984. These functions are part of the Timers option and need not
  985. be available on all implementations.
  986. clock_getcpuclockid()
  987. clock_nanosleep()
  988. mq_timedreceive()
  989. mq_timedsend()
  990. posix_fadvise()
  991. posix_fallocate()
  992. posix_madvise()
  993. posix_memalign()
  994. posix_mem_offset()
  995. posix_spawnattr_destroy(), posix_spawnattr_init()
  996. posix_spawnattr_getflags(), posix_spawnattr_setflags()
  997. posix_spawnattr_getpgroup(), posix_spawnattr_setpgroup()
  998. posix_spawnattr_getschedparam(), posix_spawnattr_setschedparam()
  999. posix_spawnattr_getschedpolicy(), posix_spawnattr_setschedpolicy()
  1000. posix_spawnattr_getsigdefault(), posix_spawnattr_setsigdefault()
  1001. posix_spawnattr_getsigmask(), posix_spawnattr_setsigmask()
  1002. posix_spawn_file_actions_addclose()
  1003. posix_spawn_file_actions_adddup2()
  1004. posix_spawn_file_actions_addopen()
  1005. posix_spawn_file_actions_destroy()
  1006. posix_spawn_file_actions_init()
  1007. posix_spawn()
  1008. posix_spawnp()
  1009. posix_typed_mem_get_info()
  1010. pthread_mutex_timedlock()
  1011. sem_timedwait()
  1012. #config UCLIBC_HAS_TERMIOS
  1013. # bool "termios functions"
  1014. # default y
  1015. # help
  1016. # Get and set terminal attributes, line control, get and set baud
  1017. # rate.
  1018. # termios(), tcgetattr(), tcsetattr(), tcsendbreak(), tcdrain(),
  1019. # tcflush(), tcflow(), cfmakeraw(), cfgetospeed(), cfgetispeed(),
  1020. # cfsetispeed(), cfsetospeed(), cfsetspeed()
  1021. #
  1022. # If unsure, say Y.
  1023. config UCLIBC_HAS_EPOLL
  1024. bool "epoll"
  1025. default y
  1026. help
  1027. epoll_create(), epoll_ctl(), epoll_wait() functions.
  1028. config UCLIBC_HAS_XATTR
  1029. bool "Extended Attributes"
  1030. default y
  1031. help
  1032. Extended Attributes support.
  1033. setxattr()
  1034. lsetxattr()
  1035. fsetxattr()
  1036. getxattr()
  1037. lgetxattr()
  1038. fgetxattr()
  1039. listxattr()
  1040. llistxattr()
  1041. flistxattr()
  1042. removexattr()
  1043. lremovexattr()
  1044. fremovexattr()
  1045. Say N unless you need support for extended attributes and the
  1046. filesystems do actually support them.
  1047. config UCLIBC_HAS_PROFILING
  1048. bool "Profiling support"
  1049. default y
  1050. help
  1051. gcc's -finstrument-functions needs these.
  1052. Most people can safely answer N.
  1053. config UCLIBC_HAS_CRYPT_IMPL
  1054. bool "libcrypt support"
  1055. default y
  1056. help
  1057. libcrypt contains crypt(), setkey() and encrypt()
  1058. config UCLIBC_HAS_SHA256_CRYPT_IMPL
  1059. bool "libcrypt SHA256 support"
  1060. depends on UCLIBC_HAS_CRYPT_IMPL
  1061. help
  1062. This adds support for SHA256 password hashing via the crypt() function.
  1063. Say N here if you do not need SHA256 crypt support.
  1064. config UCLIBC_HAS_SHA512_CRYPT_IMPL
  1065. bool "libcrypt SHA512 support"
  1066. depends on UCLIBC_HAS_CRYPT_IMPL
  1067. help
  1068. This adds support for SHA512 password hashing via the crypt() function.
  1069. Say N here if you do not need SHA512 crypt support.
  1070. config UCLIBC_HAS_CRYPT_STUB
  1071. bool "libcrypt stubs"
  1072. default y
  1073. depends on !UCLIBC_HAS_CRYPT_IMPL
  1074. help
  1075. Standards mandate that crypt(3) provides a stub if it is unavailable.
  1076. If you enable this option then stubs for
  1077. crypt(), setkey() and encrypt()
  1078. will be provided in a small libcrypt.
  1079. config UCLIBC_HAS_CRYPT
  1080. def_bool y
  1081. depends on UCLIBC_HAS_CRYPT_IMPL || UCLIBC_HAS_CRYPT_STUB
  1082. endmenu
  1083. menuconfig UCLIBC_HAS_NETWORK_SUPPORT
  1084. bool "Networking Support"
  1085. default y
  1086. help
  1087. Say N here if you do not need network support.
  1088. if UCLIBC_HAS_NETWORK_SUPPORT
  1089. config UCLIBC_HAS_SOCKET
  1090. bool "Socket support"
  1091. default y
  1092. help
  1093. If you want to include support for sockets then answer Y.
  1094. config UCLIBC_HAS_IPV4
  1095. bool "IP version 4 support"
  1096. default y
  1097. select UCLIBC_HAS_SOCKET
  1098. help
  1099. If you want to include support for the Internet Protocol
  1100. (IP version 4) then answer Y.
  1101. Most people will say Y.
  1102. config UCLIBC_HAS_IPV6
  1103. bool "IP version 6 support"
  1104. select UCLIBC_HAS_SOCKET
  1105. help
  1106. If you want to include support for the next version of the Internet
  1107. Protocol (IP version 6) then answer Y.
  1108. Most people should answer N.
  1109. config UCLIBC_USE_NETLINK
  1110. bool "Use netlink to query interfaces"
  1111. depends on UCLIBC_HAS_SOCKET
  1112. help
  1113. In newer versions of Linux (2.4.17+), support was added for querying
  1114. network device information via netlink rather than the old style
  1115. ioctl's. Most of the time, the older ioctl style is sufficient (and
  1116. it is smaller than netlink), but if you find that not all of your
  1117. devices are being returned by the if_nameindex() function, you will
  1118. have to use the netlink implementation.
  1119. Most people can safely answer N.
  1120. config UCLIBC_SUPPORT_AI_ADDRCONFIG
  1121. bool "Support the AI_ADDRCONFIG flag"
  1122. depends on UCLIBC_USE_NETLINK
  1123. help
  1124. The implementation of AI_ADDRCONFIG is aligned with the glibc
  1125. implementation using netlink to query interfaces to find both
  1126. ipv4 and ipv6 support. This is only needed if an application uses
  1127. the AI_ADDRCONFIG flag.
  1128. Most people can safely answer N.
  1129. config UCLIBC_HAS_BSD_RES_CLOSE
  1130. bool "Support res_close() (bsd-compat)"
  1131. help
  1132. Answer Y if you desperately want to support BSD compatibility in
  1133. the network code.
  1134. Most people will say N.
  1135. config UCLIBC_HAS_COMPAT_RES_STATE
  1136. bool "Use compatible but bloated _res"
  1137. default y
  1138. help
  1139. Answer Y if you build network utilities and they muck with resolver
  1140. internals a lot (_res global structure). uclibc does not use most
  1141. of _res.XXX fields, and with this option OFF they won't even exist.
  1142. Which will make e.g. dig build fail.
  1143. Answering N saves around 400 bytes in bss.
  1144. config UCLIBC_HAS_EXTRA_COMPAT_RES_STATE
  1145. bool "Use extra compatible but extra bloated _res"
  1146. help
  1147. Answer Y if selecting UCLIBC_HAS_COMPAT_RES_STATE is not enough.
  1148. As far as I can say, this should never be needed.
  1149. config UCLIBC_HAS_RESOLVER_SUPPORT
  1150. bool "DNS resolver functions"
  1151. select UCLIBC_HAS_COMPAT_RES_STATE
  1152. depends on UCLIBC_HAS_IPV4 || UCLIBC_HAS_IPV6
  1153. help
  1154. Provide implementations for DNS resolver functions.
  1155. In particular, the following functions will be added to the
  1156. library:
  1157. ns_skiprr, ns_initparse, ns_parserr, ns_msg_getflag,
  1158. res_mkquery, res_init, res_ninit, res_close, res_nclose
  1159. res_query, res_search, res_querydomain,
  1160. dn_expand, dn_comp,
  1161. ns_name_uncompress, ns_name_ntop, ns_name_pton, ns_name_unpack,
  1162. ns_name_pack, ns_name_compress, ns_name_skip, dn_skipname,
  1163. ns_get16, ns_get32, ns_put16, ns_put32
  1164. choice
  1165. prompt "DNS Query ID generation"
  1166. default UCLIBC_DNSRAND_MODE_PRNGPLUS
  1167. help
  1168. Control how successive dns query ids' are generated during
  1169. dns lookup.
  1170. config UCLIBC_DNSRAND_MODE_URANDOM
  1171. bool "urandom"
  1172. help
  1173. "urandom" uses /dev/urandom available under many unix flavours
  1174. to generate dns query id. This can generate good random ids,
  1175. by dipping into the entropy pool maintained by the system.
  1176. However this is relatively slow compared to the other options,
  1177. as it may involve cryptographic operations internally and
  1178. kernel-userspace handshake.
  1179. config UCLIBC_DNSRAND_MODE_CLOCK
  1180. bool "clock"
  1181. depends on UCLIBC_HAS_REALTIME
  1182. help
  1183. "clock" uses CLOCK_REALTIME of the system to generate plausibly
  1184. random dns query id. Systems require to have clock source with
  1185. nanosec granularity mapped to this clock id for this to generate
  1186. plausibly random values. However has processor and io performances
  1187. improve in future, its effectiveness can get impacted.
  1188. config UCLIBC_DNSRAND_MODE_PRNGPLUS
  1189. bool "prngplus"
  1190. help
  1191. "prngplus" uses random prng available within uclibc, to indirectly
  1192. generate the dns query id. This tries to provide a good balance
  1193. between speed and randomness to an extent. It periodically reseeds
  1194. the prng using random value generated from either the urandom or
  1195. else the clock, if either of them is available. Additionally applies
  1196. transform (one way, if possible) on internal generated random values.
  1197. These make it difficult to infer internal state of prng from unbroken
  1198. sequences of exposed random values.
  1199. This is the default.
  1200. config UCLIBC_DNSRAND_MODE_SIMPLECOUNTER
  1201. bool "simplecounter"
  1202. help
  1203. "simplecounter" uses a simple counter to generate dns query id.
  1204. This is a very simple logic and can be subjected to dns poison
  1205. attack relatively easily.
  1206. It is recommended to avoid this option.
  1207. endchoice
  1208. endif
  1209. menu "String and Stdio Support"
  1210. config UCLIBC_HAS_STRING_GENERIC_OPT
  1211. bool "Use faster (but larger) generic string functions"
  1212. default y
  1213. help
  1214. Answer Y to use the (tweaked) glibc generic string functions.
  1215. In general, they are faster (but 3-5K larger) than the base
  1216. uClibc string functions which are optimized solely for size.
  1217. Many people will answer Y.
  1218. config UCLIBC_HAS_STRING_ARCH_OPT
  1219. bool "Use arch-specific assembly string functions (where available)"
  1220. default y
  1221. help
  1222. Answer Y to use any archtecture-specific assembly language string
  1223. functions available for this target plaform.
  1224. Note that assembly implementations are not available for all string
  1225. functions, so some generic (written in C) string functions may
  1226. still be used.
  1227. These are small and fast, the only reason _not_ to say Y here is
  1228. for debugging purposes.
  1229. config UCLIBC_HAS_STDIO_FUTEXES
  1230. bool "Use futexes for multithreaded I/O locking"
  1231. depends on UCLIBC_HAS_THREADS_NATIVE
  1232. help
  1233. If you want to compile uClibc to use futexes for low-level
  1234. I/O locking, answer Y. Otherwise, answer N.
  1235. config UCLIBC_HAS_CTYPE_TABLES
  1236. bool "Use Table Versions Of 'ctype.h' Functions."
  1237. default y
  1238. help
  1239. Answer Y to use table versions of the 'ctype.h' functions.
  1240. While the non-table versions are often smaller when building
  1241. statically linked apps, they work only in stub locale mode.
  1242. Most people will answer Y.
  1243. config UCLIBC_HAS_CTYPE_SIGNED
  1244. bool "Support Signed Characters In 'ctype.h' Functions."
  1245. depends on UCLIBC_HAS_CTYPE_TABLES
  1246. default y
  1247. help
  1248. Answer Y to enable support for passing signed char values to
  1249. the 'ctype.h' functions. ANSI/ISO C99 and SUSv3 specify that
  1250. these functions are only defined for unsigned char values and
  1251. EOF. However, glibc allows negative signed char values as well
  1252. in order to support 'broken old programs'.
  1253. Most people will answer Y.
  1254. choice
  1255. prompt "ctype argument checking"
  1256. depends on UCLIBC_HAS_CTYPE_TABLES
  1257. default UCLIBC_HAS_CTYPE_UNSAFE
  1258. help
  1259. Please select the invalid arg behavior you want for the 'ctype'
  1260. functions.
  1261. The 'ctype' functions are now implemented using table lookups, with
  1262. the arg being the index. This can result in incorrect memory accesses
  1263. or even segfaults for args outside of the allowed range.
  1264. NOTE: This only affects the 'ctype' _functions_. It does not affect
  1265. the macro implementations.
  1266. config UCLIBC_HAS_CTYPE_UNSAFE
  1267. bool "Do not check -- unsafe"
  1268. config UCLIBC_HAS_CTYPE_CHECKED
  1269. bool "Detect and handle appropriately"
  1270. config UCLIBC_HAS_CTYPE_ENFORCED
  1271. bool "Issue a diagnostic and abort()"
  1272. endchoice
  1273. config UCLIBC_HAS_WCHAR
  1274. bool "Wide Character Support"
  1275. help
  1276. Answer Y to enable wide character support. This will make uClibc
  1277. much larger. It is also currently required for locale support.
  1278. Most people will answer N.
  1279. config UCLIBC_HAS_LIBICONV
  1280. bool "Iconv Support"
  1281. select UCLIBC_HAS_WCHAR
  1282. help
  1283. Add tiny iconv support for charset conversion from and to UTF-8.
  1284. config UCLIBC_HAS_LIBINTL
  1285. bool "Intl stubs support"
  1286. help
  1287. If you enable this option you get stubs for the gettext family of
  1288. functions.
  1289. config UCLIBC_HAS_LOCALE
  1290. bool "Locale Support"
  1291. select UCLIBC_HAS_WCHAR
  1292. select UCLIBC_HAS_CTYPE_TABLES
  1293. select UCLIBC_HAS_LIBICONV
  1294. help
  1295. uClibc now has full ANSI/ISO C99 locale support (except for
  1296. wcsftime() and collating items in regex). Be aware that enabling
  1297. this option will make uClibc much larger.
  1298. Enabling UCLIBC_HAS_LOCALE with the default set of supported locales
  1299. (169 UTF-8 locales, and 144 locales for other codesets) will enlarge
  1300. uClibc by around 300k. You can reduce this size by building your own
  1301. custom set of locate data (see extra/locale/LOCALES for details).
  1302. uClibc's locale support is still under development. For example,
  1303. codesets using shift states are not currently supported. Support is
  1304. planned in the next iteration of locale support.
  1305. Answer Y to enable locale support. Most people will answer N.
  1306. choice
  1307. prompt "Locale data"
  1308. depends on UCLIBC_HAS_LOCALE
  1309. default UCLIBC_BUILD_MINIMAL_LOCALE
  1310. config UCLIBC_BUILD_MINIMAL_LOCALE
  1311. bool "Only selected locales"
  1312. depends on UCLIBC_HAS_LOCALE
  1313. help
  1314. If you do not need all locales that are available on your
  1315. host-box, then set this to 'Y'.
  1316. config UCLIBC_BUILD_ALL_LOCALE
  1317. bool "All locales"
  1318. depends on UCLIBC_HAS_LOCALE
  1319. help
  1320. This builds all the locales that are available on your
  1321. host-box.
  1322. endchoice
  1323. config UCLIBC_BUILD_MINIMAL_LOCALES
  1324. string "locales to use"
  1325. depends on UCLIBC_BUILD_MINIMAL_LOCALE
  1326. default "en_US"
  1327. help
  1328. Space separated list of locales to use.
  1329. E.g.:
  1330. en_US en_GB de_AT
  1331. default:
  1332. en_US
  1333. config UCLIBC_HAS_XLOCALE
  1334. bool "Extended Locale Support (experimental/incomplete)"
  1335. depends on UCLIBC_HAS_LOCALE
  1336. help
  1337. Answer Y to enable extended locale support similar to that provided
  1338. by glibc. This is primarily intended to support libstd++
  1339. functionality.
  1340. However, it also allows thread-specific locale selection via
  1341. uselocale().
  1342. Most people will answer N.
  1343. config UCLIBC_HAS_HEXADECIMAL_FLOATS
  1344. bool "Support hexadecimal float notation"
  1345. depends on UCLIBC_HAS_CTYPE_TABLES
  1346. depends on UCLIBC_HAS_FLOATS
  1347. help
  1348. Answer Y to enable support for hexadecimal float notation in the
  1349. (wchar and) char string to floating point conversion functions, as
  1350. well as support for the %a and %A conversion specifiers in the
  1351. *printf() and *scanf() functions.
  1352. Most people will answer N.
  1353. config UCLIBC_HAS_GLIBC_DIGIT_GROUPING
  1354. bool "Support glibc's \"'\" flag for allowing locale-specific digit grouping"
  1355. depends on UCLIBC_HAS_LOCALE
  1356. depends on UCLIBC_HAS_FLOATS
  1357. help
  1358. Answer Y to enable support for glibc's \"'\" flag for allowing
  1359. locale-specific digit grouping in base 10 integer conversions and
  1360. appropriate floating point conversions in the *printf() and *scanf()
  1361. functions.
  1362. Most people will answer N.
  1363. config UCLIBC_HAS_SCANF_LENIENT_DIGIT_GROUPING
  1364. bool "Do not require digit grouping when the \"'\" flag is specified"
  1365. depends on UCLIBC_HAS_GLIBC_DIGIT_GROUPING
  1366. default y
  1367. help
  1368. Answer Y to make digit grouping optional when the \"'\" flag is
  1369. specified.
  1370. This is the standard glibc behavior. If the initial string of digits
  1371. exceeds the maximum group number, the input will be treated as a
  1372. normal non-grouped number.
  1373. Most people will answer N.
  1374. config UCLIBC_HAS_GLIBC_CUSTOM_PRINTF
  1375. bool "Support glibc's register_printf_function() (glibc-compat)"
  1376. depends on !USE_OLD_VFPRINTF
  1377. help
  1378. Answer Y to support glibc's register_printf_function() to allow an
  1379. application to add its own printf conversion specifiers.
  1380. parse_printf_format() is also enabled.
  1381. NOTE: Limits the number or registered specifiers to 10.
  1382. NOTE: Requires new conversion specifiers to be ASCII
  1383. characters (0-0x7f). This is to avoid problems with processing
  1384. format strings in locales with different multibyte conversions.
  1385. Most people will answer N.
  1386. config USE_OLD_VFPRINTF
  1387. bool "Use the old vfprintf implementation"
  1388. depends on !UCLIBC_HAS_WCHAR
  1389. help
  1390. Set to true to use the old vfprintf instead of the new. This is
  1391. roughly C89 compliant with some extensions, and is much smaller.
  1392. However, it does not support wide chars, positional args, or glibc
  1393. custom printf specifiers.
  1394. Most people will answer N.
  1395. config UCLIBC_PRINTF_SCANF_POSITIONAL_ARGS
  1396. int "Maximum number of positional args. Either 0 or >= 9."
  1397. depends on !USE_OLD_VFPRINTF
  1398. default 9
  1399. help
  1400. Set the maximum number of positional args supported by the
  1401. printf/scanf functions. The Single Unix Specification Version 3
  1402. requires a minimum value of 9. Setting this to a value lower than
  1403. 9 will disable positional arg support and cause the NL_ARGMAX macro
  1404. in limits.h to be #undef'd.
  1405. WARNING! The workspace to support positional args is currently
  1406. allocated on the stack. You probably don't want to set
  1407. this to too high a value.
  1408. Most people will answer 9.
  1409. choice
  1410. prompt "Stdio buffer size"
  1411. default UCLIBC_HAS_STDIO_BUFSIZ_4096
  1412. help
  1413. Please select a value for BUFSIZ. This will be used by the
  1414. stdio subsystem as the default buffer size for a file, and
  1415. affects fopen(), setvbuf(), etc.
  1416. NOTE: Setting this to 'none' will disable buffering completely.
  1417. However, BUFSIZ will still be defined in stdio.h as 256 because
  1418. many applications use this value.
  1419. config UCLIBC_HAS_STDIO_BUFSIZ_NONE
  1420. bool "none (WARNING - BUFSIZ will be 256 in stdio.h)"
  1421. depends on !UCLIBC_HAS_WCHAR
  1422. config UCLIBC_HAS_STDIO_BUFSIZ_256
  1423. bool "256 (minimum ANSI/ISO C99 value)"
  1424. config UCLIBC_HAS_STDIO_BUFSIZ_512
  1425. bool "512"
  1426. config UCLIBC_HAS_STDIO_BUFSIZ_1024
  1427. bool "1024"
  1428. config UCLIBC_HAS_STDIO_BUFSIZ_2048
  1429. bool "2048"
  1430. config UCLIBC_HAS_STDIO_BUFSIZ_4096
  1431. bool "4096"
  1432. config UCLIBC_HAS_STDIO_BUFSIZ_8192
  1433. bool "8192"
  1434. # If you add more choices, you will need to update uClibc_stdio.h.
  1435. endchoice
  1436. choice
  1437. prompt "Stdio builtin buffer size (uClibc-specific)"
  1438. depends on !UCLIBC_HAS_STDIO_BUFSIZ_NONE
  1439. default UCLIBC_HAS_STDIO_BUILTIN_BUFFER_NONE
  1440. help
  1441. When a FILE is created with fopen(), an attempt is made to allocate
  1442. a BUFSIZ buffer for it. If the allocation fails, fopen() will still
  1443. succeed but the FILE will be unbuffered.
  1444. This option adds a small amount of space to each FILE to act as an
  1445. emergency buffer in the event of a buffer allocation failure.
  1446. Most people will answer None.
  1447. config UCLIBC_HAS_STDIO_BUILTIN_BUFFER_NONE
  1448. bool "None"
  1449. config UCLIBC_HAS_STDIO_BUILTIN_BUFFER_4
  1450. bool "4"
  1451. config UCLIBC_HAS_STDIO_BUILTIN_BUFFER_8
  1452. bool "8"
  1453. # If you add more choices, you will need to update uClibc_stdio.h.
  1454. endchoice
  1455. config UCLIBC_HAS_STDIO_SHUTDOWN_ON_ABORT
  1456. bool "Attempt to shutdown stdio subsystem when abort() is called."
  1457. help
  1458. ANSI/ISO C99 requires abort() to be asyn-signal-safe. So there was
  1459. a behavioral change made in SUSv3. Previously, abort() was required
  1460. to have the affect of fclose() on all open streams. The wording has
  1461. been changed to "may" from "shall".
  1462. Most people will answer N.
  1463. config UCLIBC_HAS_STDIO_GETC_MACRO
  1464. bool "Provide a macro version of getc()"
  1465. depends on !UCLIBC_HAS_STDIO_BUFSIZ_NONE
  1466. default y
  1467. help
  1468. Provide a macro version of getc().
  1469. Most people will answer Y.
  1470. config UCLIBC_HAS_STDIO_PUTC_MACRO
  1471. bool "Provide a macro version of putc()"
  1472. depends on !UCLIBC_HAS_STDIO_BUFSIZ_NONE
  1473. default y
  1474. help
  1475. Provide a macro version of putc().
  1476. Most people will answer Y.
  1477. config UCLIBC_HAS_STDIO_AUTO_RW_TRANSITION
  1478. bool "Support auto-r/w transition"
  1479. default y
  1480. help
  1481. Answer Y to enable the stdio subsystem to automaticly transition
  1482. between reading and writing. This relaxes the ANSI/ISO C99
  1483. requirement:
  1484. When a file is opened with update mode ('+' as the second or third
  1485. character in the list of mode argument values), both input and output
  1486. may be performed on the associated stream. However, output shall not
  1487. be directly followed by input without an intervening call to the
  1488. fflush function or to a file positioning function (fseek, fsetpos,
  1489. or rewind), and input shall not be directly followed by output without
  1490. an intervening call to a file positioning function, unless the input
  1491. operation encounters end­of­file.
  1492. Most people will answer Y.
  1493. config UCLIBC_HAS_FOPEN_LARGEFILE_MODE
  1494. bool "Support an fopen() 'F' flag for large file mode (uClibc-specific)"
  1495. help
  1496. Answer Y to enable a uClibc-specific extension to allow passing an
  1497. additional 'F' flag in the mode string for fopen() to specify that
  1498. the file should be open()ed with the O_LARGEFILE flag set.
  1499. Most people will answer N.
  1500. config UCLIBC_HAS_FOPEN_EXCLUSIVE_MODE
  1501. bool "Support an fopen() 'x' flag for exclusive mode (glibc-compat)"
  1502. help
  1503. Answer Y to support a glibc extension to allow passing
  1504. additional 'x' flag in the mode string for fopen() to specify that
  1505. the file should be open()ed with the O_EXCL flag set.
  1506. Most people will answer N.
  1507. config UCLIBC_HAS_FOPEN_CLOSEEXEC_MODE
  1508. bool "Support an fopen() 'e' flag for close-on-exec mode (glibc-compat)"
  1509. help
  1510. Answer Y to support a glibc extension to allow passing
  1511. additional 'e' flag in the mode string for fopen() to specify that
  1512. the file should be open()ed with the O_CLOEXEC flag set.
  1513. Most people will answer N.
  1514. config UCLIBC_HAS_GLIBC_CUSTOM_STREAMS
  1515. bool "Support fmemopen(), open_memstream(), and fopencookie() (glibc-compat)"
  1516. help
  1517. Answer Y to support the glibc 'custom stream' extension functions
  1518. fmemopen(), open_memstream(), and fopencookie().
  1519. NOTE: There are some minor differences regarding seeking behavior.
  1520. Most people will answer N.
  1521. config UCLIBC_HAS_PRINTF_M_SPEC
  1522. bool "Support the '%m' specifier in printf format strings (glibc-compat)"
  1523. help
  1524. Answer Y to support a glibc extension to interpret '%m' in printf
  1525. format strings as an instruction to output the error message string
  1526. (as generated by strerror) corresponding to the current value of
  1527. 'errno'.
  1528. Most people will answer N.
  1529. config UCLIBC_HAS_ERRNO_MESSAGES
  1530. bool "Include the errno message text in the library"
  1531. default y
  1532. help
  1533. Answer Y if you want to include the errno message text in the
  1534. library. This adds about 3K to the library, but enables strerror()
  1535. to generate text other than 'Unknown error <number>'.
  1536. Most people will answer Y.
  1537. config UCLIBC_HAS_SYS_ERRLIST
  1538. bool "Support sys_errlist[] (obsolete-compat)"
  1539. depends on UCLIBC_HAS_ERRNO_MESSAGES
  1540. help
  1541. Answer Y if you want to support the obsolete sys_errlist[].
  1542. This adds about 0.5k to the library, except for the mips
  1543. arch where it adds over 4K.
  1544. WARNING! In the future, support for sys_errlist[] may be unavailable
  1545. in at least some configurations. In fact, it may be removed
  1546. altogether.
  1547. Most people will answer N.
  1548. Application writers: use the strerror(3) function.
  1549. config UCLIBC_HAS_SIGNUM_MESSAGES
  1550. bool "Include the signum message text in the library"
  1551. default y
  1552. help
  1553. Answer Y if you want to include the signum message text in the
  1554. library. This adds about 0.5K to the library, but enables strsignal()
  1555. to generate text other than 'Unknown signal <number>'.
  1556. Most people will answer Y.
  1557. config UCLIBC_HAS_SYS_SIGLIST
  1558. bool "Support sys_siglist[] (bsd-compat)"
  1559. depends on UCLIBC_HAS_SIGNUM_MESSAGES
  1560. help
  1561. Answer Y if you want to support sys_siglist[].
  1562. WARNING! In the future, support for sys_siglist[] may be unavailable
  1563. in at least some configurations. In fact, it may be removed
  1564. altogether.
  1565. Most people will answer N.
  1566. config UCLIBC_HAS_GNU_GETOPT
  1567. bool "Support gnu getopt"
  1568. default y
  1569. help
  1570. Answer Y if you want to include full gnu getopt() instead of a
  1571. (much smaller) SUSv3 compatible getopt().
  1572. Note that getopt_long, getopt_long_only as well as getsubopt
  1573. are implemented on top of this choice.
  1574. Most people will answer Y.
  1575. config UCLIBC_HAS_GETOPT_LONG
  1576. bool "Support getopt_long/getopt_long_only (glibc-compat)"
  1577. default y
  1578. help
  1579. Answer Y if you want to include getopt_long[_only()] used by many
  1580. apps.
  1581. Most people will answer Y.
  1582. config UCLIBC_HAS_GNU_GETSUBOPT
  1583. bool "Support getsubopt"
  1584. default y
  1585. help
  1586. Answer Y if you want to include getsubopt().
  1587. Most people will answer Y.
  1588. config UCLIBC_HAS_ARGP
  1589. bool "Support argp"
  1590. select UCLIBC_HAS_GETOPT_LONG
  1591. select UCLIBC_HAS_GNU_GETOPT
  1592. select UCLIBC_HAS_WCHAR
  1593. default n
  1594. help
  1595. Argp is an interface for parsing unix-style argument vectors. Unlike
  1596. the common getopt interface, it provides many advanced features in
  1597. addition to parsing options, such as automatic output in response to
  1598. `--help' and `--version' options.
  1599. A library can export an argp option parser, which programs can easily
  1600. use in conjunction with their own option parser.
  1601. Argp support is needed by elfutils libdw.
  1602. Most people can safely answer N.
  1603. endmenu
  1604. menu "Big and Tall"
  1605. config UCLIBC_HAS_REGEX
  1606. bool "Regular Expression Support"
  1607. default y
  1608. help
  1609. POSIX regular expression code is really big -- 53k all by itself.
  1610. If you don't use regular expressions, turn this off and save space.
  1611. Of course, if you only statically link, leave this on, since it will
  1612. only be included in your apps if you use regular expressions.
  1613. config UCLIBC_HAS_FNMATCH
  1614. bool "fnmatch Support"
  1615. default y
  1616. help
  1617. POSIX fnmatch.
  1618. config UCLIBC_HAS_WORDEXP
  1619. bool "Support the wordexp() interface"
  1620. depends on UCLIBC_HAS_GLOB
  1621. help
  1622. The SuSv3 wordexp() interface performs word expansions per the Shell
  1623. and Utilities volume of IEEE Std 1003.1-2001, Section 2.6. It is
  1624. intended for use by applications that want to implement all of the
  1625. standard Bourne shell expansions on input data.
  1626. This interface is rarely used, and very large. Unless you have a
  1627. pressing need for wordexp(), you should probably answer N.
  1628. config UCLIBC_HAS_NFTW
  1629. bool "Support the nftw() interface"
  1630. help
  1631. The SuSv3 nftw() interface is used to recursively descend
  1632. directory paths while repeatedly calling a function.
  1633. This interface is rarely used, and adds around 4.5k. Unless you have
  1634. a pressing need for nftw(), you should probably answer N.
  1635. config UCLIBC_HAS_FTW
  1636. bool "Support the ftw() interface (SUSv4-obsolete)"
  1637. depends on UCLIBC_SUSV4_LEGACY
  1638. help
  1639. The SuSv3 ftw() interface is used to recursively descend
  1640. directory paths while repeatedly calling a function.
  1641. This interface is rarely used, and adds around 4.5k. Unless you have
  1642. a pressing need for ftw(), you should probably answer N.
  1643. config UCLIBC_HAS_FTS
  1644. bool "Support the fts() interface (bsd-compat)"
  1645. help
  1646. The fts functions are provided for traversing UNIX file hierarchies.
  1647. This interface is currently used by the elfutils and adds
  1648. around 7.5k.
  1649. You should port your application to use the POSIX nftw()
  1650. interface.
  1651. Unless you need to build/use elfutils, you should prolly answer N.
  1652. config UCLIBC_HAS_GLOB
  1653. bool "Support the glob() interface"
  1654. depends on UCLIBC_HAS_FNMATCH
  1655. default y
  1656. help
  1657. The glob interface is somewhat large (weighing in at about 2,5k). It
  1658. is used fairly often, but is an option since people wanting to go for
  1659. absolute minimum size may wish to omit it.
  1660. Most people will answer Y.
  1661. config UCLIBC_HAS_GNU_GLOB
  1662. bool "Support gnu glob() interface"
  1663. depends on UCLIBC_HAS_GLOB
  1664. help
  1665. The gnu glob interface is somewhat larger (weighing in at about 4,2k)
  1666. than it's SuSv3 counterpart (and is out of date). It is an old copy
  1667. from glibc and does not support all the GNU specific options.
  1668. Answer Y if you want to include full gnu glob() instead of the smaller
  1669. SUSv3 compatible glob().
  1670. Most people will answer N.
  1671. endmenu
  1672. menu "Library Installation Options"
  1673. config RUNTIME_PREFIX
  1674. string "uClibc runtime library directory"
  1675. default "/usr/$(TARGET_ARCH)-linux-uclibc/"
  1676. help
  1677. RUNTIME_PREFIX is the directory into which the uClibc runtime
  1678. libraries will be installed. The result will look something
  1679. like the following:
  1680. $(RUNTIME_PREFIX)/
  1681. lib/ <contains all runtime libraries>
  1682. usr/bin/ldd <the ldd utility program>
  1683. sbin/ldconfig <the ldconfig utility program>
  1684. This value is used by the 'make install' Makefile target. Since this
  1685. directory is compiled into the shared library loader, you will need to
  1686. recompile uClibc if you change this value...
  1687. For a typical target system this should be set to "/", such that
  1688. 'make install' will install /lib/libuClibc-<VERSION>.so
  1689. config DEVEL_PREFIX
  1690. string "uClibc development environment directory"
  1691. default "/usr/$(TARGET_ARCH)-linux-uclibc/usr/"
  1692. help
  1693. DEVEL_PREFIX is the directory into which the uClibc development
  1694. environment will be installed. The result will look something
  1695. like the following:
  1696. $(DEVEL_PREFIX)/
  1697. lib/ <contains static libs>
  1698. include/ <Where all the header files go>
  1699. This value is used by the 'make install' Makefile target when
  1700. installing a uClibc development environment.
  1701. For a typical target system this should be set to "/usr", such that
  1702. 'make install' will install /usr/include/<header files>.
  1703. config MULTILIB_DIR
  1704. string "library path component"
  1705. default "lib"
  1706. help
  1707. Path component where libraries reside.
  1708. For a typical target system this should be set to "lib", such that
  1709. 'make install' will install libraries to "/lib" and "/usr/lib"
  1710. respectively
  1711. DEVEL_PREFIX/MULTILIB_DIR
  1712. RUNTIME_PREFIX/MULTILIB_DIR
  1713. Other settings may include "lib32" or "lib64".
  1714. config HARDWIRED_ABSPATH
  1715. bool "Hardwire absolute paths into linker scripts"
  1716. default y
  1717. help
  1718. This prepends absolute paths to the libraries mentioned in linker
  1719. scripts such as libc.so.
  1720. This is a build time optimization. It has no impact on dynamic
  1721. linking at runtime, which doesn't use linker scripts.
  1722. You must disable this to use uClibc with old non-sysroot toolchains,
  1723. such as the prebuilt binary cross compilers at:
  1724. http://uclibc.org/downloads/binaries
  1725. The amount of time saved by this optimization is actually too small to
  1726. measure. The linker just had to search the library path to find the
  1727. linker script, so the dentries are cache hot if it has to search the
  1728. same path again. But it's what glibc does, so we do it too.
  1729. endmenu
  1730. menu "Security options"
  1731. config UCLIBC_BUILD_PIE
  1732. bool "Build utilities as ET_DYN/PIE executables"
  1733. depends on HAVE_SHARED
  1734. depends on TARGET_arm || TARGET_frv || TARGET_i386 || TARGET_mips || TARGET_powerpc || TARGET_nds32
  1735. select FORCE_SHAREABLE_TEXT_SEGMENTS
  1736. help
  1737. If you answer Y here, ldd and iconv are built as ET_DYN/PIE
  1738. executables.
  1739. It requires gcc-3.4 and binutils-2.15 (for arm 2.16) or later.
  1740. More about ET_DYN/PIE binaries on <http://pax.grsecurity.net/> .
  1741. WARNING: This option also enables FORCE_SHAREABLE_TEXT_SEGMENTS, so
  1742. all libraries have to be built with -fPIC or -fpic, and all
  1743. assembler functions must be written as position independent
  1744. code (PIC).
  1745. config HAVE_NO_SSP
  1746. bool
  1747. config UCLIBC_HAS_SSP
  1748. bool "Support for GCC stack smashing protector"
  1749. depends on !HAVE_NO_SSP
  1750. help
  1751. Add code to support GCC's -fstack-protector[-all] option to uClibc.
  1752. This requires GCC 4.1 or newer. GCC does not have to provide libssp,
  1753. the needed functions are added to ldso/libc instead.
  1754. GCC's stack protector is a reimplementation of IBM's propolice.
  1755. See http://www.trl.ibm.com/projects/security/ssp/ and
  1756. http://www.linuxfromscratch.org/hints/downloads/files/ssp.txt
  1757. for details.
  1758. Note that NOEXECSTACK on a kernel with address space randomization
  1759. is generally sufficient to prevent most buffer overflow exploits
  1760. without increasing code size. This option essentially adds debugging
  1761. code to catch them.
  1762. Most people will answer N.
  1763. config SSP_QUICK_CANARY
  1764. bool "Use simple guard values without accessing /dev/urandom"
  1765. depends on UCLIBC_HAS_SSP
  1766. help
  1767. Use gettimeofday(2) to define the __guard without accessing
  1768. /dev/urandom.
  1769. WARNING: This makes smashing stack protector vulnerable to timing
  1770. attacks.
  1771. Most people will answer N.
  1772. choice
  1773. prompt "Propolice protection blocking signal"
  1774. depends on UCLIBC_HAS_SSP
  1775. depends on DODEBUG
  1776. default PROPOLICE_BLOCK_SEGV
  1777. help
  1778. "abort" use SIGABRT to block offending programs.
  1779. This is the default implementation.
  1780. "segfault" use SIGSEGV to block offending programs.
  1781. Use this for debugging.
  1782. If unsure, answer "abort".
  1783. config PROPOLICE_BLOCK_ABRT
  1784. bool "abort"
  1785. config PROPOLICE_BLOCK_SEGV
  1786. bool "segfault"
  1787. endchoice
  1788. config UCLIBC_BUILD_SSP
  1789. bool "Build uClibc with -fstack-protector"
  1790. depends on UCLIBC_HAS_SSP
  1791. help
  1792. Build all uClibc libraries and executables with -fstack-protector,
  1793. adding extra stack overflow checking to most uClibc functions.
  1794. config UCLIBC_BUILD_RELRO
  1795. bool "Build uClibc with linker option -z RELRO"
  1796. depends on HAVE_SHARED
  1797. default y
  1798. help
  1799. Build all libraries and executables with "ld -z relro".
  1800. This tells the linker to mark chunks of an executable or shared
  1801. library read-only after applying dynamic relocations. (This comes
  1802. up when a global const variable is initialized to the address of a
  1803. function or the value of another global variable.)
  1804. This is a fairly obscure option the ld man page doesn't even bother
  1805. to document properly. It's a security paranoia issue that's more
  1806. likely to consume memory (by allocating an extra page) rather than
  1807. save it.
  1808. This is explained in more depth at
  1809. http://www.airs.com/blog/archives/189
  1810. Nobody is likely to care whether you say Y or N here.
  1811. config UCLIBC_BUILD_NOW
  1812. bool "Build uClibc with linker option -z NOW"
  1813. depends on HAVE_SHARED
  1814. help
  1815. Build all libraries and executables with "ld -z now".
  1816. This tells the linker to resolve all symbols when the library is
  1817. first loaded, rather than when each function is first called. This
  1818. increases start-up latency by a few microseconds and may do
  1819. unnecessary work (resolving symbols that are never used), but the
  1820. realtime people like it for making microbenchmark timings slightly
  1821. more predictable and in some cases it can be slightly faster due to
  1822. CPU cache behavior (not having to fault the linker back in to do
  1823. lazy symbol resolution).
  1824. Most people can't tell the difference between selecting Y or N here.
  1825. config UCLIBC_BUILD_NOEXECSTACK
  1826. bool "Build uClibc with noexecstack marking"
  1827. default y
  1828. help
  1829. Mark all assembler files as noexecstack, which will mark uClibc
  1830. as not requiring an executable stack. (This doesn't prevent other
  1831. files you link against from claiming to need an executable stack, it
  1832. just won't cause uClibc to request it unnecessarily.)
  1833. This is a security thing to make buffer overflows harder to exploit.
  1834. By itself, it's kind of useless, as Linus Torvalds explained in 1998:
  1835. http://old.lwn.net/1998/0806/a/linus-noexec.html
  1836. It only actually provides any security when combined with address
  1837. space randomization, explained here: http://lwn.net/Articles/121845/
  1838. Address space randomization is on by default in current linux
  1839. kernels (although it can be disabled using the option
  1840. CONFIG_COMPAT_BRK).
  1841. You should probably say Y.
  1842. endmenu
  1843. menu "Development/debugging options"
  1844. config CROSS_COMPILER_PREFIX
  1845. string "Cross-compiling toolchain prefix"
  1846. default ""
  1847. help
  1848. The prefix used to execute your cross-compiling toolchain. For
  1849. example, if you run 'arm-linux-uclibc-gcc' to compile something,
  1850. then enter 'arm-linux-uclibc-' here.
  1851. config UCLIBC_EXTRA_CFLAGS
  1852. string "Extra CFLAGS"
  1853. default ""
  1854. help
  1855. Add any additional CFLAGS to be used to build uClibc.
  1856. config DODEBUG
  1857. bool "Enable debugging symbols"
  1858. select EXTRA_WARNINGS
  1859. help
  1860. Say Y here if you wish to compile uClibc with debugging symbols.
  1861. This will allow you to use a debugger to examine uClibc internals
  1862. while applications are running. This increases the size of the
  1863. library considerably and should only be used when doing development.
  1864. If you are doing development and want to debug uClibc, answer Y.
  1865. Otherwise, answer N.
  1866. config DODEBUG_PT
  1867. bool "Build pthread with debugging output"
  1868. depends on UCLIBC_HAS_THREADS && UCLIBC_HAS_LINUXTHREADS
  1869. help
  1870. Enable debug output in libpthread. This is only useful when doing
  1871. development in libpthread itself.
  1872. Otherwise, answer N.
  1873. config DOSTRIP
  1874. bool "Strip libraries and executables"
  1875. default y
  1876. depends on !DODEBUG
  1877. help
  1878. Say Y here if you do wish to strip all uClibc libraries and
  1879. executables. No stripping increases the size of the binaries
  1880. considerably, but makes it possible to debug uClibc libraries.
  1881. Most people will answer Y.
  1882. config DOASSERTS
  1883. bool "Build with run-time assertion testing"
  1884. help
  1885. Say Y here to include runtime assertion tests.
  1886. This enables runtime assertion testing in some code, which can
  1887. increase the size of the library and incur runtime overhead.
  1888. If you say N, then this testing will be disabled.
  1889. config SUPPORT_LD_DEBUG
  1890. bool "Build the shared library loader with debugging support"
  1891. depends on HAVE_SHARED
  1892. help
  1893. Answer Y here to enable all the extra code needed to debug the uClibc
  1894. native shared library loader. The level of debugging noise that is
  1895. generated depends on the LD_DEBUG environment variable... Just set
  1896. LD_DEBUG to something like: 'LD_DEBUG=token1,token2,.. prog' to
  1897. debug your application. Diagnostic messages will then be printed to
  1898. the stderr.
  1899. For now these debugging tokens are available:
  1900. detail provide more information for some options
  1901. move display copy processing
  1902. symbols display symbol table processing
  1903. reloc display relocation processing; detail shows the
  1904. relocation patch
  1905. nofixups never fixes up jump relocations
  1906. bindings displays the resolve processing (function calls);
  1907. detail shows the relocation patch
  1908. vdso display vdso symbol table processing
  1909. all Enable everything!
  1910. The additional environment variable:
  1911. LD_DEBUG_OUTPUT=file
  1912. redirects the diagnostics to an output file created using
  1913. the specified name and the process id as a suffix.
  1914. An excellent start is simply:
  1915. $ LD_DEBUG=binding,move,symbols,reloc,detail ./appname
  1916. or to log everything to a file named 'logfile', try this
  1917. $ LD_DEBUG=all LD_DEBUG_OUTPUT=logfile ./appname
  1918. If you are doing development and want to debug uClibc's shared library
  1919. loader, answer Y. Mere mortals answer N.
  1920. config SUPPORT_LD_DEBUG_EARLY
  1921. bool "Build the shared library loader with early debugging support"
  1922. depends on HAVE_SHARED
  1923. help
  1924. Answer Y here to if you find the uClibc shared library loader is
  1925. crashing or otherwise not working very early on. This is typical
  1926. only when starting a new port when you haven't figured out how to
  1927. properly get the values for argc, argv, environ, etc. This method
  1928. allows a degree of visibility into the very early shared library
  1929. loader initialization process. If you are doing development and want
  1930. to debug the uClibc shared library loader early initialization,
  1931. answer Y. Mere mortals answer N.
  1932. config UCLIBC_MALLOC_DEBUGGING
  1933. bool "Build malloc with debugging support"
  1934. depends on MALLOC || MALLOC_STANDARD
  1935. select DOASSERTS
  1936. help
  1937. Answer Y here to compile extra debugging support code into malloc.
  1938. Malloc debugging output may then be enabled at runtime using the
  1939. MALLOC_DEBUG environment variable.
  1940. The value of MALLOC_DEBUG should be an integer, which is interpreted
  1941. as a bitmask with the following bits:
  1942. 1 - do extra consistency checking
  1943. 2 - output messages for malloc/free calls and OS
  1944. allocation calls
  1945. 4 - output messages for the `MMB' layer
  1946. 8 - output messages for internal malloc heap manipulation
  1947. calls
  1948. Because this increases the size of malloc appreciably (due to strings
  1949. etc), you should say N unless you need to debug a malloc problem.
  1950. config UCLIBC_HAS_BACKTRACE
  1951. bool "Add support for application self-debugging"
  1952. depends on HAVE_SHARED
  1953. help
  1954. Answer Y here to compile support for application self-debugging that
  1955. provides the following new functions:
  1956. backtrace, backtrace_symbols, backtrace_symbols_fd
  1957. The backtrace functionality is currently supported on some platforms, and it
  1958. based on dwarf2 informations to properly work, so any application that
  1959. want to use backtrace needs to be built with -fexceptions flag.
  1960. The symbol names may be unavailable without the use of special linker
  1961. options. For systems using the GNU linker, it is necessary to use the
  1962. -rdynamic linker option too. Note that names of "static" functions are not
  1963. exposed, and won't be available in the backtrace.
  1964. config WARNINGS
  1965. string "Compiler Warnings"
  1966. default "-Wall"
  1967. help
  1968. Set this to the set of compiler warnings you wish to see while compiling.
  1969. config EXTRA_WARNINGS
  1970. bool "Enable extra annoying warnings"
  1971. help
  1972. If you wish to build with extra warnings enabled, say Y here.
  1973. endmenu