LXR toybox/lib/portability.h

   1// Workarounds for horrible build environment idiosyncrasies.
   2
   3// Instead of polluting the code with strange #ifdefs to work around bugs
   4// in specific compiler, library, or OS versions, localize all that here
   5// and in portability.c
   6
   7// For musl
   8#define _ALL_SOURCE
   9#ifndef REG_STARTEND
  10#define REG_STARTEND 0
  11#endif
  12
  13#ifdef __APPLE__
  14// macOS 10.13 doesn't have the POSIX 2008 direct access to timespec in
  15// struct stat, but we can ask it to give us something equivalent...
  16// (This must come before any #include!)
  17#define _DARWIN_C_SOURCE
  18// ...and then use macros to paper over the difference.
  19#define st_atim st_atimespec
  20#define st_ctim st_ctimespec
  21#define st_mtim st_mtimespec
  22#endif
  23
  24// Test for gcc (using compiler builtin #define)
  25
  26#ifdef __GNUC__
  27#define printf_format   __attribute__((format(printf, 1, 2)))
  28#else
  29#define printf_format
  30#endif
  31
  32// Always use long file support.
  33#define _FILE_OFFSET_BITS 64
  34
  35// This isn't in the spec, but it's how we determine what libc we're using.
  36
  37// Types various replacement prototypes need.
  38// This also lets us determine what libc we're using. Systems that
  39// have <features.h> will transitively include it, and ones that don't --
  40// macOS -- won't break.
  41#include <sys/types.h>
  42
  43// Various constants old build environments might not have even if kernel does
  44
  45#ifndef AT_FDCWD
  46#define AT_FDCWD -100
  47#endif
  48
  49#ifndef AT_SYMLINK_NOFOLLOW
  50#define AT_SYMLINK_NOFOLLOW 0x100
  51#endif
  52
  53#ifndef AT_REMOVEDIR
  54#define AT_REMOVEDIR 0x200
  55#endif
  56
  57#ifndef RLIMIT_RTTIME
  58#define RLIMIT_RTTIME 15
  59#endif
  60
  61// Introduced in Linux 3.1
  62#ifndef SEEK_DATA
  63#define SEEK_DATA 3
  64#endif
  65#ifndef SEEK_HOLE
  66#define SEEK_HOLE 4
  67#endif
  68
  69// We don't define GNU_dammit because we're not part of the gnu project, and
  70// don't want to get any FSF on us. Unfortunately glibc (gnu libc)
  71// won't give us Linux syscall wrappers without claiming to be part of the
  72// gnu project (because Stallman's "GNU owns Linux" revisionist history
  73// crusade includes the kernel, even though Linux was inspired by Minix).
  74
  75// We use most non-posix Linux syscalls directly through the syscall() wrapper,
  76// but even many posix-2008 functions aren't provided by glibc unless you
  77// claim it's in the name of Gnu.
  78
  79#if defined(__GLIBC__)
  80// "Function prototypes shall be provided." but aren't.
  81// http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/unistd.h.html
  82char *crypt(const char *key, const char *salt);
  83
  84// According to posix, #include header, get a function definition. But glibc...
  85// http://pubs.opengroup.org/onlinepubs/9699919799/functions/wcwidth.html
  86#include <wchar.h>
  87int wcwidth(wchar_t wc);
  88
  89// see http://pubs.opengroup.org/onlinepubs/9699919799/functions/strptime.html
  90#include <time.h>
  91char *strptime(const char *buf, const char *format, struct tm *tm);
  92
  93// They didn't like posix basename so they defined another function with the
  94// same name and if you include libgen.h it #defines basename to something
  95// else (where they implemented the real basename), and that define breaks
  96// the table entry for the basename command. They didn't make a new function
  97// with a different name for their new behavior because gnu.
  98//
  99// Solution: don't use their broken header, provide an inline to redirect the
 100// correct name to the broken name.
 101
 102char *dirname(char *path);
 103char *__xpg_basename(char *path);
 104static inline char *basename(char *path) { return __xpg_basename(path); }
 105char *strcasestr(const char *haystack, const char *needle);
 106void *memmem(const void *haystack, size_t haystack_length,
 107  const void *needle, size_t needle_length);
 108#endif // defined(glibc)
 109
 110// getopt_long(), getopt_long_only(), and struct option.
 111#include <getopt.h>
 112
 113#if !defined(__GLIBC__)
 114// POSIX basename.
 115#include <libgen.h>
 116#endif
 117
 118// Work out how to do endianness
 119
 120#ifdef __APPLE__
 121
 122#include <libkern/OSByteOrder.h>
 123
 124#ifdef __BIG_ENDIAN__
 125#define IS_BIG_ENDIAN 1
 126#else
 127#define IS_BIG_ENDIAN 0
 128#endif
 129
 130#define bswap_16(x) OSSwapInt16(x)
 131#define bswap_32(x) OSSwapInt32(x)
 132#define bswap_64(x) OSSwapInt64(x)
 133
 134#elif defined(__FreeBSD__)
 135
 136#include <sys/endian.h>
 137
 138#if _BYTE_ORDER == _BIG_ENDIAN
 139#define IS_BIG_ENDIAN 1
 140#else
 141#define IS_BIG_ENDIAN 0
 142#endif
 143
 144#else
 145
 146#include <byteswap.h>
 147#include <endian.h>
 148
 149#if __BYTE_ORDER == __BIG_ENDIAN
 150#define IS_BIG_ENDIAN 1
 151#else
 152#define IS_BIG_ENDIAN 0
 153#endif
 154
 155#endif
 156
 157#if IS_BIG_ENDIAN
 158#define IS_LITTLE_ENDIAN 0
 159#define SWAP_BE16(x) (x)
 160#define SWAP_BE32(x) (x)
 161#define SWAP_BE64(x) (x)
 162#define SWAP_LE16(x) bswap_16(x)
 163#define SWAP_LE32(x) bswap_32(x)
 164#define SWAP_LE64(x) bswap_64(x)
 165#else
 166#define IS_LITTLE_ENDIAN 1
 167#define SWAP_BE16(x) bswap_16(x)
 168#define SWAP_BE32(x) bswap_32(x)
 169#define SWAP_BE64(x) bswap_64(x)
 170#define SWAP_LE16(x) (x)
 171#define SWAP_LE32(x) (x)
 172#define SWAP_LE64(x) (x)
 173#endif
 174
 175// Linux headers not listed by POSIX or LSB
 176#include <sys/mount.h>
 177#ifdef __linux__
 178#include <sys/statfs.h>
 179#include <sys/swap.h>
 180#include <sys/sysinfo.h>
 181#endif
 182
 183#ifdef __APPLE__
 184#include <util.h>
 185#elif !defined(__FreeBSD__)
 186#include <pty.h>
 187#else
 188#include <termios.h>
 189#ifndef IUTF8
 190#define IUTF8 0
 191#endif
 192#endif
 193
 194#if defined(__APPLE__) || defined(__linux__)
 195// Linux and macOS has both have getxattr and friends in <sys/xattr.h>, but
 196// they aren't compatible.
 197#include <sys/xattr.h>
 198ssize_t xattr_get(const char *, const char *, void *, size_t);
 199ssize_t xattr_lget(const char *, const char *, void *, size_t);
 200ssize_t xattr_fget(int fd, const char *, void *, size_t);
 201ssize_t xattr_list(const char *, char *, size_t);
 202ssize_t xattr_llist(const char *, char *, size_t);
 203ssize_t xattr_flist(int, char *, size_t);
 204ssize_t xattr_set(const char*, const char*, const void*, size_t, int);
 205ssize_t xattr_lset(const char*, const char*, const void*, size_t, int);
 206ssize_t xattr_fset(int, const char*, const void*, size_t, int);
 207#endif
 208
 209// macOS doesn't have these functions, but we can fake them.
 210#ifdef __APPLE__
 211int mknodat(int, const char*, mode_t, dev_t);
 212int posix_fallocate(int, off_t, off_t);
 213#endif
 214
 215// Android is missing some headers and functions
 216// "generated/config.h" is included first
 217#if CFG_TOYBOX_SHADOW
 218#include <shadow.h>
 219#endif
 220#if CFG_TOYBOX_UTMPX
 221#include <utmpx.h>
 222#else
 223struct utmpx {int ut_type;};
 224#define USER_PROCESS 0
 225static inline struct utmpx *getutxent(void) {return 0;}
 226static inline void setutxent(void) {;}
 227static inline void endutxent(void) {;}
 228#endif
 229
 230// Some systems don't define O_NOFOLLOW, and it varies by architecture, so...
 231#include <fcntl.h>
 232#ifndef O_NOFOLLOW
 233#define O_NOFOLLOW 0
 234#endif
 235#ifndef O_NOATIME
 236#define O_NOATIME 01000000
 237#endif
 238#ifndef O_CLOEXEC
 239#define O_CLOEXEC 02000000
 240#endif
 241#ifndef O_PATH
 242#define O_PATH   010000000
 243#endif
 244#ifndef SCHED_RESET_ON_FORK
 245#define SCHED_RESET_ON_FORK (1<<30)
 246#endif
 247
 248// Glibc won't give you linux-kernel constants unless you say "no, a BUD lite"
 249// even though linux has nothing to do with the FSF and never has.
 250#ifndef F_SETPIPE_SZ
 251#define F_SETPIPE_SZ 1031
 252#endif
 253
 254#ifndef F_GETPIPE_SZ
 255#define F_GETPIPE_SZ 1032
 256#endif
 257
 258#if defined(__SIZEOF_DOUBLE__) && defined(__SIZEOF_LONG__) \
 259    && __SIZEOF_DOUBLE__ <= __SIZEOF_LONG__
 260typedef double FLOAT;
 261#else
 262typedef float FLOAT;
 263#endif
 264
 265#ifndef __uClinux__
 266pid_t xfork(void);
 267#endif
 268
 269//#define strncpy(...) @@strncpyisbadmmkay@@
 270//#define strncat(...) @@strncatisbadmmkay@@
 271
 272// Support building the Android tools on glibc, so hermetic AOSP builds can
 273// use toybox before they're ready to switch to host bionic.
 274#ifdef __BIONIC__
 275#include <android/log.h>
 276#else
 277typedef enum android_LogPriority {
 278  ANDROID_LOG_UNKNOWN = 0,
 279  ANDROID_LOG_DEFAULT,
 280  ANDROID_LOG_VERBOSE,
 281  ANDROID_LOG_DEBUG,
 282  ANDROID_LOG_INFO,
 283  ANDROID_LOG_WARN,
 284  ANDROID_LOG_ERROR,
 285  ANDROID_LOG_FATAL,
 286  ANDROID_LOG_SILENT,
 287} android_LogPriority;
 288static inline int __android_log_write(int pri, const char *tag, const char *msg)
 289{
 290  return -1;
 291}
 292#endif
 293
 294// libprocessgroup is an Android platform library not included in the NDK.
 295#if defined(__BIONIC__)
 296#if __has_include(<processgroup/sched_policy.h>)
 297#include <processgroup/sched_policy.h>
 298#define GOT_IT
 299#endif
 300#endif
 301#ifdef GOT_IT
 302#undef GOT_IT
 303#else
 304static inline int get_sched_policy(int tid, void *policy) {return 0;}
 305static inline char *get_sched_policy_name(int policy) {return "unknown";}
 306#endif
 307
 308// Android NDKv18 has liblog.so but not liblog.c for static builds,
 309// stub it out for now.
 310#ifdef __ANDROID_NDK__
 311#define __android_log_write(a, b, c) (0)
 312#endif
 313
 314#ifndef SYSLOG_NAMES
 315typedef struct {char *c_name; int c_val;} CODE;
 316extern CODE prioritynames[], facilitynames[];
 317#endif
 318
 319#if CFG_TOYBOX_GETRANDOM
 320#include <sys/random.h>
 321#endif
 322int xgetrandom(void *buf, unsigned len, unsigned flags);
 323
 324// Android's bionic libc doesn't have confstr.
 325#ifdef __BIONIC__
 326#define _CS_PATH        0
 327#define _CS_V7_ENV      1
 328#include <string.h>
 329static inline void confstr(int a, char *b, int c) {strcpy(b, a ? "POSIXLY_CORRECT=1" : "/bin:/usr/bin");}
 330#endif
 331
 332// Paper over the differences between BSD kqueue and Linux inotify for tail.
 333
 334struct xnotify {
 335  char **paths;
 336  int max, *fds, count, kq;
 337};
 338
 339struct xnotify *xnotify_init(int max);
 340int xnotify_add(struct xnotify *not, int fd, char *path);
 341int xnotify_wait(struct xnotify *not, char **path);
 342
 343#ifdef __APPLE__
 344#define f_frsize f_iosize
 345#endif
 346
 347int sig_to_num(char *s);
 348char *num_to_sig(int sig);
 349
 350struct signame {
 351  int num;
 352  char *name;
 353};
 354void xsignal_all_killers(void *handler);
 355
 356// Different OSes encode major/minor device numbers differently.
 357int dev_minor(int dev);
 358int dev_major(int dev);
 359int dev_makedev(int major, int minor);
 360
 361char *fs_type_name(struct statfs *statfs);
 362
 363int get_block_device_size(int fd, unsigned long long *size);
 364