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1/* vi: set sw=4 ts=4: */
2/*
3 * Copyright 2006, Bernhard Reutner-Fischer
4 *
5 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
6 */
7#ifndef BB_PLATFORM_H
8#define BB_PLATFORM_H 1
9
10
11/* Convenience macros to test the version of gcc. */
12#undef __GNUC_PREREQ
13#if defined __GNUC__ && defined __GNUC_MINOR__
14# define __GNUC_PREREQ(maj, min) \
15 ((__GNUC__ << 16) + __GNUC_MINOR__ >= ((maj) << 16) + (min))
16#else
17# define __GNUC_PREREQ(maj, min) 0
18#endif
19
20/* __restrict is known in EGCS 1.2 and above. */
21#if !__GNUC_PREREQ(2,92)
22# ifndef __restrict
23# define __restrict
24# endif
25#endif
26
27#if !__GNUC_PREREQ(2,7)
28# ifndef __attribute__
29# define __attribute__(x)
30# endif
31#endif
32
33#undef inline
34#if defined(__STDC_VERSION__) && __STDC_VERSION__ > 199901L
35/* it's a keyword */
36#elif __GNUC_PREREQ(2,7)
37# define inline __inline__
38#else
39# define inline
40#endif
41
42#ifndef __const
43# define __const const
44#endif
45
46#define UNUSED_PARAM __attribute__ ((__unused__))
47#define NORETURN __attribute__ ((__noreturn__))
48/* "The malloc attribute is used to tell the compiler that a function
49 * may be treated as if any non-NULL pointer it returns cannot alias
50 * any other pointer valid when the function returns. This will often
51 * improve optimization. Standard functions with this property include
52 * malloc and calloc. realloc-like functions have this property as long
53 * as the old pointer is never referred to (including comparing it
54 * to the new pointer) after the function returns a non-NULL value."
55 */
56#define RETURNS_MALLOC __attribute__ ((malloc))
57#define PACKED __attribute__ ((__packed__))
58#define ALIGNED(m) __attribute__ ((__aligned__(m)))
59
60/* __NO_INLINE__: some gcc's do not honor inlining! :( */
61#if __GNUC_PREREQ(3,0) && !defined(__NO_INLINE__)
62# define ALWAYS_INLINE __attribute__ ((always_inline)) inline
63/* I've seen a toolchain where I needed __noinline__ instead of noinline */
64# define NOINLINE __attribute__((__noinline__))
65# if !ENABLE_WERROR
66# define DEPRECATED __attribute__ ((__deprecated__))
67# define UNUSED_PARAM_RESULT __attribute__ ((warn_unused_result))
68# else
69# define DEPRECATED
70# define UNUSED_PARAM_RESULT
71# endif
72#else
73# define ALWAYS_INLINE inline
74# define NOINLINE
75# define DEPRECATED
76# define UNUSED_PARAM_RESULT
77#endif
78
79/* -fwhole-program makes all symbols local. The attribute externally_visible
80 * forces a symbol global. */
81#if __GNUC_PREREQ(4,1)
82# define EXTERNALLY_VISIBLE __attribute__(( visibility("default") ))
83//__attribute__ ((__externally_visible__))
84#else
85# define EXTERNALLY_VISIBLE
86#endif
87
88/* At 4.4 gcc become much more anal about this, need to use "aliased" types */
89#if __GNUC_PREREQ(4,4)
90# define FIX_ALIASING __attribute__((__may_alias__))
91#else
92# define FIX_ALIASING
93#endif
94
95/* We use __extension__ in some places to suppress -pedantic warnings
96 * about GCC extensions. This feature didn't work properly before
97 * gcc 2.8. */
98#if !__GNUC_PREREQ(2,8)
99# ifndef __extension__
100# define __extension__
101# endif
102#endif
103
104/* FAST_FUNC is a qualifier which (possibly) makes function call faster
105 * and/or smaller by using modified ABI. It is usually only needed
106 * on non-static, busybox internal functions. Recent versions of gcc
107 * optimize statics automatically. FAST_FUNC on static is required
108 * only if you need to match a function pointer's type */
109#if __GNUC_PREREQ(3,0) && defined(i386) /* || defined(__x86_64__)? */
110/* stdcall makes callee to pop arguments from stack, not caller */
111# define FAST_FUNC __attribute__((regparm(3),stdcall))
112/* #elif ... - add your favorite arch today! */
113#else
114# define FAST_FUNC
115#endif
116
117/* Make all declarations hidden (-fvisibility flag only affects definitions) */
118/* (don't include system headers after this until corresponding pop!) */
119#if __GNUC_PREREQ(4,1) && !defined(__CYGWIN__)
120# define PUSH_AND_SET_FUNCTION_VISIBILITY_TO_HIDDEN _Pragma("GCC visibility push(hidden)")
121# define POP_SAVED_FUNCTION_VISIBILITY _Pragma("GCC visibility pop")
122#else
123# define PUSH_AND_SET_FUNCTION_VISIBILITY_TO_HIDDEN
124# define POP_SAVED_FUNCTION_VISIBILITY
125#endif
126
127/* gcc-2.95 had no va_copy but only __va_copy. */
128#if !__GNUC_PREREQ(3,0)
129# include <stdarg.h>
130# if !defined va_copy && defined __va_copy
131# define va_copy(d,s) __va_copy((d),(s))
132# endif
133#endif
134
135
136/* ---- Endian Detection ------------------------------------ */
137
138#include <limits.h>
139#if defined(__digital__) && defined(__unix__)
140# include <sex.h>
141#elif defined(__FreeBSD__) || defined(__OpenBSD__) || defined(__NetBSD__) \
142 || defined(__APPLE__)
143# include <sys/resource.h> /* rlimit */
144# include <machine/endian.h>
145# define bswap_64 __bswap64
146# define bswap_32 __bswap32
147# define bswap_16 __bswap16
148#else
149# include <byteswap.h>
150# include <endian.h>
151#endif
152
153#if defined(__BYTE_ORDER) && __BYTE_ORDER == __BIG_ENDIAN
154# define BB_BIG_ENDIAN 1
155# define BB_LITTLE_ENDIAN 0
156#elif defined(__BYTE_ORDER) && __BYTE_ORDER == __LITTLE_ENDIAN
157# define BB_BIG_ENDIAN 0
158# define BB_LITTLE_ENDIAN 1
159#elif defined(_BYTE_ORDER) && _BYTE_ORDER == _BIG_ENDIAN
160# define BB_BIG_ENDIAN 1
161# define BB_LITTLE_ENDIAN 0
162#elif defined(_BYTE_ORDER) && _BYTE_ORDER == _LITTLE_ENDIAN
163# define BB_BIG_ENDIAN 0
164# define BB_LITTLE_ENDIAN 1
165#elif defined(BYTE_ORDER) && BYTE_ORDER == BIG_ENDIAN
166# define BB_BIG_ENDIAN 1
167# define BB_LITTLE_ENDIAN 0
168#elif defined(BYTE_ORDER) && BYTE_ORDER == LITTLE_ENDIAN
169# define BB_BIG_ENDIAN 0
170# define BB_LITTLE_ENDIAN 1
171#elif defined(__386__)
172# define BB_BIG_ENDIAN 0
173# define BB_LITTLE_ENDIAN 1
174#else
175# error
176# error
177# error "Can't determine endianness !"
178# error "DO NOT USE 'MAKE' TO BUILD BIONIC BUSYBOX"
179# error
180# error
181 exit 1
182#endif
183
184#if ULONG_MAX > 0xffffffff
185# define bb_bswap_64(x) bswap_64(x)
186#endif
187
188/* SWAP_LEnn means "convert CPU<->little_endian by swapping bytes" */
189#if BB_BIG_ENDIAN
190# define SWAP_BE16(x) (x)
191# define SWAP_BE32(x) (x)
192# define SWAP_BE64(x) (x)
193# define SWAP_LE16(x) bswap_16(x)
194# define SWAP_LE32(x) bswap_32(x)
195# define SWAP_LE64(x) bb_bswap_64(x)
196# define IF_BIG_ENDIAN(...) __VA_ARGS__
197# define IF_LITTLE_ENDIAN(...)
198#else
199# define SWAP_BE16(x) bswap_16(x)
200# define SWAP_BE32(x) bswap_32(x)
201# define SWAP_BE64(x) bb_bswap_64(x)
202# define SWAP_LE16(x) (x)
203# define SWAP_LE32(x) (x)
204# define SWAP_LE64(x) (x)
205# define IF_BIG_ENDIAN(...)
206# define IF_LITTLE_ENDIAN(...) __VA_ARGS__
207#endif
208
209
210/* ---- Unaligned access ------------------------------------ */
211
212#include <stdint.h>
213typedef int bb__aliased_int FIX_ALIASING;
214typedef long bb__aliased_long FIX_ALIASING;
215typedef uint16_t bb__aliased_uint16_t FIX_ALIASING;
216typedef uint32_t bb__aliased_uint32_t FIX_ALIASING;
217typedef uint64_t bb__aliased_uint64_t FIX_ALIASING;
218
219/* NB: unaligned parameter should be a pointer, aligned one -
220 * a lvalue. This makes it more likely to not swap them by mistake
221 */
222#if defined(i386) || defined(__x86_64__) || defined(__powerpc__)
223# define move_from_unaligned_int(v, intp) ((v) = *(bb__aliased_int*)(intp))
224# define move_from_unaligned_long(v, longp) ((v) = *(bb__aliased_long*)(longp))
225# define move_from_unaligned16(v, u16p) ((v) = *(bb__aliased_uint16_t*)(u16p))
226# define move_from_unaligned32(v, u32p) ((v) = *(bb__aliased_uint32_t*)(u32p))
227# define move_to_unaligned16(u16p, v) (*(bb__aliased_uint16_t*)(u16p) = (v))
228# define move_to_unaligned32(u32p, v) (*(bb__aliased_uint32_t*)(u32p) = (v))
229/* #elif ... - add your favorite arch today! */
230#else
231/* performs reasonably well (gcc usually inlines memcpy here) */
232# define move_from_unaligned_int(v, intp) (memcpy(&(v), (intp), sizeof(int)))
233# define move_from_unaligned_long(v, longp) (memcpy(&(v), (longp), sizeof(long)))
234# define move_from_unaligned16(v, u16p) (memcpy(&(v), (u16p), 2))
235# define move_from_unaligned32(v, u32p) (memcpy(&(v), (u32p), 4))
236# define move_to_unaligned16(u16p, v) do { \
237 uint16_t __t = (v); \
238 memcpy((u16p), &__t, 2); \
239} while (0)
240# define move_to_unaligned32(u32p, v) do { \
241 uint32_t __t = (v); \
242 memcpy((u32p), &__t, 4); \
243} while (0)
244#endif
245
246
247/* ---- Size-saving "small" ints (arch-dependent) ----------- */
248
249#if defined(i386) || defined(__x86_64__) || defined(__mips__) || defined(__cris__)
250/* add other arches which benefit from this... */
251typedef signed char smallint;
252typedef unsigned char smalluint;
253#else
254/* for arches where byte accesses generate larger code: */
255typedef int smallint;
256typedef unsigned smalluint;
257#endif
258
259/* ISO C Standard: 7.16 Boolean type and values <stdbool.h> */
260#if (defined __digital__ && defined __unix__)
261/* old system without (proper) C99 support */
262# define bool smalluint
263#else
264/* modern system, so use it */
265# include <stdbool.h>
266#endif
267
268
269/*----- Kernel versioning ------------------------------------*/
270
271#define KERNEL_VERSION(a,b,c) (((a) << 16) + ((b) << 8) + (c))
272
273#ifdef __UCLIBC__
274# define UCLIBC_VERSION KERNEL_VERSION(__UCLIBC_MAJOR__, __UCLIBC_MINOR__, __UCLIBC_SUBLEVEL__)
275#else
276# define UCLIBC_VERSION 0
277#endif
278
279
280/* ---- Miscellaneous --------------------------------------- */
281
282#if defined __GLIBC__ \
283 || defined __UCLIBC__ \
284 || defined __dietlibc__ \
285 || defined __BIONIC__ \
286 || defined _NEWLIB_VERSION
287# include <features.h>
288#endif
289
290/* Define bb_setpgrp */
291#if defined(__digital__) && defined(__unix__)
292/* use legacy setpgrp(pid_t, pid_t) for now. move to platform.c */
293# define bb_setpgrp() do { pid_t __me = getpid(); setpgrp(__me, __me); } while (0)
294#else
295# define bb_setpgrp() setpgrp()
296#endif
297
298/* fdprintf is more readable, we used it before dprintf was standardized */
299#include <unistd.h>
300#define fdprintf dprintf
301
302/* Useful for defeating gcc's alignment of "char message[]"-like data */
303#if !defined(__s390__)
304 /* on s390[x], non-word-aligned data accesses require larger code */
305# define ALIGN1 __attribute__((aligned(1)))
306# define ALIGN2 __attribute__((aligned(2)))
307# define ALIGN4 __attribute__((aligned(4)))
308#else
309/* Arches which MUST have 2 or 4 byte alignment for everything are here */
310# define ALIGN1
311# define ALIGN2
312# define ALIGN4
313#endif
314
315/*
316 * For 0.9.29 and svn, __ARCH_USE_MMU__ indicates no-mmu reliably.
317 * For earlier versions there is no reliable way to check if we are building
318 * for a mmu-less system.
319 */
320#if ENABLE_NOMMU || \
321 (defined __UCLIBC__ && \
322 UCLIBC_VERSION > KERNEL_VERSION(0, 9, 28) && \
323 !defined __ARCH_USE_MMU__)
324# define BB_MMU 0
325# define USE_FOR_NOMMU(...) __VA_ARGS__
326# define USE_FOR_MMU(...)
327#else
328# define BB_MMU 1
329# define USE_FOR_NOMMU(...)
330# define USE_FOR_MMU(...) __VA_ARGS__
331#endif
332
333#if defined(__digital__) && defined(__unix__)
334# include <standards.h>
335# include <inttypes.h>
336# define PRIu32 "u"
337# if !defined ADJ_OFFSET_SINGLESHOT && defined MOD_CLKA && defined MOD_OFFSET
338# define ADJ_OFFSET_SINGLESHOT (MOD_CLKA | MOD_OFFSET)
339# endif
340# if !defined ADJ_FREQUENCY && defined MOD_FREQUENCY
341# define ADJ_FREQUENCY MOD_FREQUENCY
342# endif
343# if !defined ADJ_TIMECONST && defined MOD_TIMECONST
344# define ADJ_TIMECONST MOD_TIMECONST
345# endif
346# if !defined ADJ_TICK && defined MOD_CLKB
347# define ADJ_TICK MOD_CLKB
348# endif
349#endif
350
351#if defined(__CYGWIN__)
352# define MAXSYMLINKS SYMLOOP_MAX
353#endif
354
355#if defined(ANDROID) || defined(__ANDROID__)
356# define BB_ADDITIONAL_PATH ":/vendor/bin:/system/sbin:/system/bin:/system/xbin"
357# define SYS_ioprio_set __NR_ioprio_set
358# define SYS_ioprio_get __NR_ioprio_get
359#endif
360
361
362/* ---- Who misses what? ------------------------------------ */
363
364/* Assume all these functions and header files exist by default.
365 * Platforms where it is not true will #undef them below.
366 */
367#define HAVE_CLEARENV 1
368#define HAVE_FDATASYNC 1
369#define HAVE_DPRINTF 1
370#define HAVE_MEMRCHR 1
371#define HAVE_MKDTEMP 1
372#define HAVE_PTSNAME_R 1
373#define HAVE_SETBIT 1
374#define HAVE_SIGHANDLER_T 1
375#define HAVE_STPCPY 1
376#define HAVE_STRCASESTR 1
377#define HAVE_STRCHRNUL 1
378#define HAVE_STRSEP 1
379#define HAVE_STRSIGNAL 1
380#define HAVE_STRVERSCMP 1
381#define HAVE_VASPRINTF 1
382#define HAVE_UNLOCKED_STDIO 1
383#define HAVE_UNLOCKED_LINE_OPS 1
384#define HAVE_GETLINE 1
385#define HAVE_XTABS 1
386#define HAVE_MNTENT_H 1
387#define HAVE_NET_ETHERNET_H 1
388#define HAVE_SYS_STATFS_H 1
389
390#if defined(__UCLIBC__) && UCLIBC_VERSION < KERNEL_VERSION(0, 9, 32)
391# undef HAVE_STRVERSCMP
392#endif
393
394#if defined(__dietlibc__)
395# undef HAVE_STRCHRNUL
396#endif
397
398#if defined(__WATCOMC__)
399# undef HAVE_DPRINTF
400# undef HAVE_GETLINE
401# undef HAVE_MEMRCHR
402# undef HAVE_MKDTEMP
403# undef HAVE_SETBIT
404# undef HAVE_STPCPY
405# undef HAVE_STRCASESTR
406# undef HAVE_STRCHRNUL
407# undef HAVE_STRSEP
408# undef HAVE_STRSIGNAL
409# undef HAVE_STRVERSCMP
410# undef HAVE_VASPRINTF
411# undef HAVE_UNLOCKED_STDIO
412# undef HAVE_UNLOCKED_LINE_OPS
413# undef HAVE_NET_ETHERNET_H
414#endif
415
416#if defined(__CYGWIN__)
417# undef HAVE_CLEARENV
418# undef HAVE_FDPRINTF
419# undef HAVE_MEMRCHR
420# undef HAVE_PTSNAME_R
421# undef HAVE_STRVERSCMP
422# undef HAVE_UNLOCKED_LINE_OPS
423#endif
424
425/* These BSD-derived OSes share many similarities */
426#if (defined __digital__ && defined __unix__) \
427 || defined __APPLE__ \
428 || defined __FreeBSD__ || defined __OpenBSD__ || defined __NetBSD__
429# undef HAVE_CLEARENV
430# undef HAVE_FDATASYNC
431# undef HAVE_GETLINE
432# undef HAVE_MNTENT_H
433# undef HAVE_PTSNAME_R
434# undef HAVE_SYS_STATFS_H
435# undef HAVE_SIGHANDLER_T
436# undef HAVE_STRVERSCMP
437# undef HAVE_XTABS
438# undef HAVE_DPRINTF
439# undef HAVE_UNLOCKED_STDIO
440# undef HAVE_UNLOCKED_LINE_OPS
441#endif
442
443#if defined(__FreeBSD__) || defined(__APPLE__)
444# undef HAVE_STRCHRNUL
445#endif
446
447#if defined(__NetBSD__)
448# define HAVE_GETLINE 1 /* Recent NetBSD versions have getline() */
449#endif
450
451#if defined(__digital__) && defined(__unix__)
452# undef HAVE_STPCPY
453#endif
454
455#if defined(ANDROID) || defined(__ANDROID__)
456# undef HAVE_DPRINTF
457# undef HAVE_STRCHRNUL
458# undef HAVE_STRVERSCMP
459# undef HAVE_UNLOCKED_LINE_OPS
460# undef HAVE_NET_ETHERNET_H
461# ifndef BIONIC_L
462# undef HAVE_STPCPY
463# endif
464#endif
465
466/*
467 * Now, define prototypes for all the functions defined in platform.c
468 * These must come after all the HAVE_* macros are defined (or not)
469 */
470
471#ifndef HAVE_DPRINTF
472extern int dprintf(int fd, const char *format, ...);
473#endif
474
475#ifndef HAVE_MEMRCHR
476extern void *memrchr(const void *s, int c, size_t n) FAST_FUNC;
477#endif
478
479#ifndef HAVE_MKDTEMP
480extern char *mkdtemp(char *template) FAST_FUNC;
481#endif
482
483#ifndef HAVE_SETBIT
484# define setbit(a, b) ((a)[(b) >> 3] |= 1 << ((b) & 7))
485# define clrbit(a, b) ((a)[(b) >> 3] &= ~(1 << ((b) & 7)))
486#endif
487
488#ifndef HAVE_SIGHANDLER_T
489typedef void (*sighandler_t)(int);
490#endif
491
492#ifndef HAVE_STPCPY
493extern char *stpcpy(char *p, const char *to_add) FAST_FUNC;
494#endif
495
496#ifndef HAVE_STRCASESTR
497extern char *strcasestr(const char *s, const char *pattern) FAST_FUNC;
498#endif
499
500#ifndef HAVE_STRCHRNUL
501extern char *strchrnul(const char *s, int c) FAST_FUNC;
502#endif
503
504#ifndef HAVE_STRSEP
505extern char *strsep(char **stringp, const char *delim) FAST_FUNC;
506#endif
507
508#ifndef HAVE_STRSIGNAL
509/* Not exactly the same: instead of "Stopped" it shows "STOP" etc */
510# define strsignal(sig) get_signame(sig)
511#endif
512
513#ifndef HAVE_VASPRINTF
514extern int vasprintf(char **string_ptr, const char *format, va_list p) FAST_FUNC;
515#endif
516
517#ifndef HAVE_GETLINE
518# include <stdio.h> /* for FILE */
519# include <sys/types.h> /* size_t */
520extern ssize_t getline(char **lineptr, size_t *n, FILE *stream) FAST_FUNC;
521#endif
522
523#if defined(__BIONIC__)
524#include "android.h"
525#endif
526
527
528#endif /* BB_PLATFORM_H */
529
generated by cgit at 2024-05-15 05:02:02 (GMT)