[thirdparty/util-linux.git] / include / c.h

/*
 * Fundamental C definitions.
 *
 * No copyright is claimed.  This code is in the public domain; do with
 * it what you wish.
 */
#ifndef UTIL_LINUX_C_H
#define UTIL_LINUX_C_H

#include <limits.h>
#include <stddef.h>
#include <stdint.h>
#include <stdio.h>
#include <unistd.h>
#include <stdarg.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <sys/types.h>
#include <grp.h>

#include <assert.h>

#ifdef HAVE_ERR_H
# include <err.h>
#endif

#ifdef HAVE_SYS_SYSMACROS_H
# include <sys/sysmacros.h>     /* for major, minor */
#endif

#ifndef LOGIN_NAME_MAX
# define LOGIN_NAME_MAX 256
#endif

#ifndef NAME_MAX
# define NAME_MAX PATH_MAX
#endif

/*
 * __GNUC_PREREQ is deprecated in favour of __has_attribute() and
 * __has_feature(). The __has macros are supported by clang and gcc>=5.
 */
#ifndef __GNUC_PREREQ
# if defined __GNUC__ && defined __GNUC_MINOR__
#  define __GNUC_PREREQ(maj, min) \
	((__GNUC__ << 16) + __GNUC_MINOR__ >= ((maj) << 16) + (min))
# else
#  define __GNUC_PREREQ(maj, min) 0
# endif
#endif

#ifdef __GNUC__

/* &a[0] degrades to a pointer: a different type from an array */
# define __must_be_array(a) \
	UL_BUILD_BUG_ON_ZERO(__builtin_types_compatible_p(__typeof__(a), __typeof__(&a[0])))

# define ignore_result(x) __extension__ ({ \
	__typeof__(x) __dummy __attribute__((__unused__)) = (x); (void) __dummy; \
})

#else /* !__GNUC__ */
# define __must_be_array(a)	0
# define __attribute__(_arg_)
# define ignore_result(x) ((void) (x))
#endif /* !__GNUC__ */


/* "restrict" keyword fallback */
#if __STDC__ != 1
# define restrict __restrict /* use implementation __ format */
#else
# ifndef __STDC_VERSION__
#  define restrict __restrict /* use implementation __ format */
# else
#  if __STDC_VERSION__ < 199901L
#   define restrict __restrict /* use implementation __ format */
#  endif
# endif
#endif


/*
 * It evaluates to 1 if the attribute/feature is supported by the current
 * compilation target. Fallback for old compilers.
 */
#ifndef __has_attribute
  #define __has_attribute(x) 0
#endif

#ifndef __has_feature
  #define __has_feature(x) 0
#endif

/*
 * Function attributes
 */
#ifndef __ul_alloc_size
# if (__has_attribute(alloc_size) && __has_attribute(warn_unused_result)) || __GNUC_PREREQ (4, 3)
#  define __ul_alloc_size(s) __attribute__((alloc_size(s), warn_unused_result))
# else
#  define __ul_alloc_size(s)
# endif
#endif

#ifndef __ul_calloc_size
# if (__has_attribute(alloc_size) && __has_attribute(warn_unused_result)) || __GNUC_PREREQ (4, 3)
#  define __ul_calloc_size(n, s) __attribute__((alloc_size(n, s), warn_unused_result))
# else
#  define __ul_calloc_size(n, s)
# endif
#endif

#if __has_attribute(returns_nonnull) || __GNUC_PREREQ (4, 9)
# define __ul_returns_nonnull __attribute__((returns_nonnull))
#else
# define __ul_returns_nonnull
#endif

/*
 * Force a compilation error if condition is true, but also produce a
 * result (of value 0 and type size_t), so the expression can be used
 * e.g. in a structure initializer (or wherever else comma expressions
 * aren't permitted).
 */
#define UL_BUILD_BUG_ON_ZERO(e) __extension__ (sizeof(struct { int:-!!(e); }))
#define BUILD_BUG_ON_NULL(e) ((void *)sizeof(struct { int:-!!(e); }))

#ifndef ARRAY_SIZE
# define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]) + __must_be_array(arr))
#endif

#ifndef PATH_MAX
# define PATH_MAX 4096
#endif

#ifndef TRUE
# define TRUE 1
#endif

#ifndef FALSE
# define FALSE 0
#endif

#ifndef min
# define min(x, y) __extension__ ({		\
	__typeof__(x) _min1 = (x);		\
	__typeof__(y) _min2 = (y);		\
	(void) (&_min1 == &_min2);		\
	_min1 < _min2 ? _min1 : _min2; })
#endif

#ifndef max
# define max(x, y) __extension__ ({		\
	__typeof__(x) _max1 = (x);		\
	__typeof__(y) _max2 = (y);		\
	(void) (&_max1 == &_max2);		\
	_max1 > _max2 ? _max1 : _max2; })
#endif

#ifndef abs_diff
# define abs_diff(x, y) __extension__ ({        \
	__typeof__(x) _a = (x);			\
	__typeof__(y) _b = (y);			\
	(void) (&_a == &_b);			\
	_a > _b ? _a - _b : _b - _a; })
#endif

#ifndef cmp_numbers
# define cmp_numbers(x, y) __extension__ ({	\
	__typeof__(x) _a = (x);			\
	__typeof__(y) _b = (y);			\
	(void) (&_a == &_b);			\
	_a == _b ? 0 : _a > _b ? 1 : -1; })
#endif


#ifndef cmp_timespec
# define cmp_timespec(a, b, CMP)		\
	(((a)->tv_sec == (b)->tv_sec)		\
	? ((a)->tv_nsec CMP (b)->tv_nsec)	\
	: ((a)->tv_sec CMP (b)->tv_sec))
#endif


#ifndef cmp_stat_mtime
# ifdef HAVE_STRUCT_STAT_ST_MTIM_TV_NSEC
#  define cmp_stat_mtime(_a, _b, CMP)	cmp_timespec(&(_a)->st_mtim, &(_b)->st_mtim, CMP)
# else
#  define cmp_stat_mtime(_a, _b, CMP)	((_a)->st_mtime CMP (_b)->st_mtime)
# endif
#endif


#ifndef offsetof
#define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER)
#endif

#ifndef sizeof_member
#define sizeof_member(TYPE, MEMBER) sizeof(((TYPE *)0)->MEMBER)
#endif

/*
 * container_of - cast a member of a structure out to the containing structure
 * @ptr:	the pointer to the member.
 * @type:	the type of the container struct this is embedded in.
 * @member:	the name of the member within the struct.
 */
#ifndef container_of
#define container_of(ptr, type, member) __extension__ ({	\
	const __typeof__( ((type *)0)->member ) *__mptr = (ptr); \
	(type *)( (char *)__mptr - offsetof(type,member) );})
#endif

#ifndef HAVE_PROGRAM_INVOCATION_SHORT_NAME
# ifdef HAVE___PROGNAME
extern char *__progname;
#  define program_invocation_short_name __progname
# else
#  ifdef HAVE_GETEXECNAME
#   define program_invocation_short_name \
		prog_inv_sh_nm_from_file(getexecname(), 0)
#  else
#   define program_invocation_short_name \
		prog_inv_sh_nm_from_file(__FILE__, 1)
#  endif
static char prog_inv_sh_nm_buf[256];
static inline char *
prog_inv_sh_nm_from_file(char *f, char stripext)
{
	char *t;

	if ((t = strrchr(f, '/')) != NULL)
		t++;
	else
		t = f;

	strncpy(prog_inv_sh_nm_buf, t, sizeof(prog_inv_sh_nm_buf) - 1);
	prog_inv_sh_nm_buf[sizeof(prog_inv_sh_nm_buf) - 1] = '\0';

	if (stripext && (t = strrchr(prog_inv_sh_nm_buf, '.')) != NULL)
		*t = '\0';

	return prog_inv_sh_nm_buf;
}
# endif
#endif


#ifndef HAVE_ERR_H
static inline void __attribute__ ((__format__ (__printf__, 4, 5)))
errmsg(char doexit, int excode, char adderr, const char *fmt, ...)
{
	fprintf(stderr, "%s: ", program_invocation_short_name);
	if (fmt != NULL) {
		va_list argp;
		va_start(argp, fmt);
		vfprintf(stderr, fmt, argp);
		va_end(argp);
		if (adderr)
			fprintf(stderr, ": ");
	}
	if (adderr)
		fprintf(stderr, "%m");
	fprintf(stderr, "\n");
	if (doexit)
		exit(excode);
}

#ifndef HAVE_ERR
# define err(E, FMT...) errmsg(1, E, 1, FMT)
#endif

#ifndef HAVE_ERRX
# define errx(E, FMT...) errmsg(1, E, 0, FMT)
#endif

#ifndef HAVE_WARN
# define warn(FMT...) errmsg(0, 0, 1, FMT)
#endif

#ifndef HAVE_WARNX
# define warnx(FMT...) errmsg(0, 0, 0, FMT)
#endif
#endif /* !HAVE_ERR_H */


static inline
__attribute__((__noreturn__))
void __err_oom(const char *file, unsigned int line)
{
	err(EXIT_FAILURE, "%s: %u: cannot allocate memory", file, line);
}
#define err_oom()	__err_oom(__FILE__, __LINE__)

#define err_nosys(exitcode, ...) \
	err(errno == ENOSYS ? EXIT_NOTSUPP : exitcode, __VA_ARGS__)


/* Don't use inline function to avoid '#include "nls.h"' in c.h
 */
#define errtryhelp(eval) __extension__ ({ \
	fprintf(stderr, _("Try '%s --help' for more information.\n"), \
			program_invocation_short_name); \
	exit(eval); \
})

/* After failed execvp() */
#define EX_EXEC_FAILED		126	/* Program located, but not usable. */
#define EX_EXEC_ENOENT		127	/* Could not find program to exec.  */
#define errexec(name)	err(errno == ENOENT ? EX_EXEC_ENOENT : EX_EXEC_FAILED, \
			_("failed to execute %s"), name)

static inline __attribute__((const)) int is_power_of_2(unsigned long num)
{
	return (num != 0 && ((num & (num - 1)) == 0));
}

#ifndef HAVE_LOFF_T
typedef int64_t loff_t;
#endif

#if !defined(HAVE_DIRFD) \
    && (!defined(HAVE_DECL_DIRFD) || HAVE_DECL_DIRFD == 0) \
    && defined(HAVE_DIR_DD_FD)
#include <dirent.h>
static inline int dirfd(DIR *d)
{
	return d->dd_fd;
}
#endif

/*
 * Fallback defines for old versions of glibc
 */
#include <fcntl.h>

#ifdef O_CLOEXEC
#define UL_CLOEXECSTR	"e"
#else
#define UL_CLOEXECSTR	""
#endif

#ifndef O_CLOEXEC
#define O_CLOEXEC 0
#endif

#ifdef __FreeBSD_kernel__
#ifndef F_DUPFD_CLOEXEC
#define F_DUPFD_CLOEXEC	17	/* Like F_DUPFD, but FD_CLOEXEC is set */
#endif
#endif


#ifndef AI_ADDRCONFIG
#define AI_ADDRCONFIG 0x0020
#endif

#ifndef IUTF8
#define IUTF8 0040000
#endif

/*
 * MAXHOSTNAMELEN replacement
 */
static inline size_t get_hostname_max(void)
{
	long len = sysconf(_SC_HOST_NAME_MAX);

	if (0 < len)
		return len;

#ifdef MAXHOSTNAMELEN
	return MAXHOSTNAMELEN;
#elif HOST_NAME_MAX
	return HOST_NAME_MAX;
#endif
	return 64;
}


static inline int drop_permissions(void)
{
	errno = 0;

	/* drop GID */
	if (setgid(getgid()) < 0)
		goto fail;

	/* drop UID */
	if (setuid(getuid()) < 0)
		goto fail;

	return 0;
fail:
	return errno ? -errno : -1;
}

/*
 * The usleep function was marked obsolete in POSIX.1-2001 and was removed
 * in POSIX.1-2008.  It was replaced with nanosleep() that provides more
 * advantages (like no interaction with signals and other timer functions).
 */
#include <time.h>

static inline int xusleep(useconds_t usec)
{
#ifdef HAVE_NANOSLEEP
	struct timespec waittime = {
		.tv_sec   =  usec / 1000000L,
		.tv_nsec  = (usec % 1000000L) * 1000
	};
	return nanosleep(&waittime, NULL);
#elif defined(HAVE_USLEEP)
	return usleep(usec);
#else
# error	"System with usleep() or nanosleep() required!"
#endif
}


#define ul_err_write(_m) ignore_result( write(STDERR_FILENO, _m, strlen(_m)) )

/*
 * warn() for signal handlers
 */
static inline void ul_sig_warn(const char *mesg)
{
	ul_err_write(program_invocation_short_name);
	ul_err_write(": ");
	ul_err_write(mesg);
	ul_err_write("\n");
}

/*
 * err() for signal handlers
 */
static inline void __attribute__((__noreturn__)) ul_sig_err(int excode, const char *mesg)
{
	ul_sig_warn(mesg);
	_exit(excode);
}

/*
 * Constant strings for usage() functions. For more info see
 * Documentation/{howto-usage-function.txt,boilerplate.c}
 */
#define USAGE_HEADER     _("\nUsage:\n")
#define USAGE_OPTIONS    _("\nOptions:\n")
#define USAGE_FUNCTIONS  _("\nFunctions:\n")
#define USAGE_COMMANDS   _("\nCommands:\n")
#define USAGE_ARGUMENTS   _("\nArguments:\n")
#define USAGE_COLUMNS    _("\nAvailable output columns:\n")
#define USAGE_DEFAULT_COLUMNS _("\nDefault columns:\n")
#define USAGE_SEPARATOR    "\n"

#define USAGE_OPTSTR_HELP     _("display this help")
#define USAGE_OPTSTR_VERSION  _("display version")

#define USAGE_HELP_OPTIONS(marg_dsc) \
		"%-" #marg_dsc "s%s\n" \
		"%-" #marg_dsc "s%s\n" \
		, " -h, --help",    USAGE_OPTSTR_HELP \
		, " -V, --version", USAGE_OPTSTR_VERSION

#define USAGE_ARG_SEPARATOR    "\n"
#define USAGE_ARG_SIZE(_name) \
		_(" %s arguments may be followed by the suffixes for\n" \
		  "   GiB, TiB, PiB, EiB, ZiB, and YiB (the \"iB\" is optional)\n"), _name

#define USAGE_MAN_TAIL(_man)   _("\nFor more details see %s.\n"), _man

#define UTIL_LINUX_VERSION _("%s from %s\n"), program_invocation_short_name, PACKAGE_STRING

#define print_version(eval) __extension__ ({ \
		printf(UTIL_LINUX_VERSION); \
		exit(eval); \
})

static inline void print_features(const char **features, const char *prefix)
{
	if (features && *features) {
		const char **p = features;
		while (p && *p) {
			if (prefix && p == features)
				printf(" (%s ", prefix);
			else
				fputs(p == features ? " (" : ", ", stdout);
			fputs(*p++, stdout);
		}
		fputc(')', stdout);
	}
}

#define UTIL_LINUX_VERSION_NOBREAK _("%s from %s"), program_invocation_short_name, PACKAGE_STRING

#define print_version_with_features(eval, features) __extension__ ({ \
		printf(UTIL_LINUX_VERSION_NOBREAK); \
		print_features(features, _("features:")); \
		fputc('\n', stdout); \
		exit(eval); \
})

/*
 * seek stuff
 */
#ifndef SEEK_DATA
# define SEEK_DATA	3
#endif
#ifndef SEEK_HOLE
# define SEEK_HOLE	4
#endif


/*
 * Macros to convert #define'itions to strings, for example
 * #define XYXXY 42
 * printf ("%s=%s\n", stringify(XYXXY), stringify_value(XYXXY));
 */
#define stringify_value(s) stringify(s)
#define stringify(s) #s

/* Detect if we're compiled with Address Sanitizer
 *  - gcc (__SANITIZE_ADDRESS__)
 *  - clang (__has_feature(address_sanitizer))
 */
#if !defined(HAS_FEATURE_ADDRESS_SANITIZER)
#  ifdef __SANITIZE_ADDRESS__
#      define HAS_FEATURE_ADDRESS_SANITIZER 1
#  elif defined(__has_feature)
#    if __has_feature(address_sanitizer)
#      define HAS_FEATURE_ADDRESS_SANITIZER 1
#    endif
#  endif
#  if !defined(HAS_FEATURE_ADDRESS_SANITIZER)
#    define HAS_FEATURE_ADDRESS_SANITIZER 0
#  endif
#endif

/*
 * UL_ASAN_BLACKLIST is a macro to tell AddressSanitizer (a compile-time
 * instrumentation shipped with Clang and GCC) to not instrument the
 * annotated function.  Furthermore, it will prevent the compiler from
 * inlining the function because inlining currently breaks the blacklisting
 * mechanism of AddressSanitizer.
 */
#if __has_feature(address_sanitizer) && __has_attribute(no_sanitize_memory) && __has_attribute(no_sanitize_address)
# define UL_ASAN_BLACKLIST __attribute__((noinline)) __attribute__((no_sanitize_memory)) __attribute__((no_sanitize_address))
#else
# define UL_ASAN_BLACKLIST	/* nothing */
#endif

/*
 * Note that sysconf(_SC_GETPW_R_SIZE_MAX) returns *initial* suggested size for
 * pwd buffer and in some cases it is not large enough. See POSIX and
 * getpwnam_r man page for more details.
 */
#define UL_GETPW_BUFSIZ	(16 * 1024)

/*
 * Darwin or other BSDs may only have MAP_ANON. To get it on Darwin we must
 * define _DARWIN_C_SOURCE before including sys/mman.h. We do this in config.h.
 */
#if !defined MAP_ANONYMOUS && defined MAP_ANON
# define MAP_ANONYMOUS  (MAP_ANON)
#endif

#define SINT_MAX(t) (((t)1 << (sizeof(t) * 8 - 2)) - (t)1 + ((t)1 << (sizeof(t) * 8 - 2)))

#endif /* UTIL_LINUX_C_H */
Commit	Line	Data
4d0dbb8b KZ	1	/*
4d0dbb8b KZ	2	* Fundamental C definitions.
40f8c5e4 KZ	3	*
	4	* No copyright is claimed. This code is in the public domain; do with
	5	* it what you wish.
4d0dbb8b	6	*/
4d0dbb8b KZ	7	#ifndef UTIL_LINUX_C_H
	8	#define UTIL_LINUX_C_H
	9
	10	#include <limits.h>
aa1f95c3	11	#include <stddef.h>
eb76ca98 FG	12	#include <stdint.h>
eb76ca98 FG	13	#include <stdio.h>
9199f5cd	14	#include <unistd.h>
eb76ca98	15	#include <stdarg.h>
4d498513	16	#include <stdlib.h>
eb76ca98 FG	17	#include <string.h>
eb76ca98 FG	18	#include <errno.h>
17fc8693 KZ	19	#include <sys/types.h>
17fc8693 KZ	20	#include <grp.h>
eb76ca98	21
2c656779 KZ	22	#include <assert.h>
2c656779 KZ	23
eb76ca98 FG	24	#ifdef HAVE_ERR_H
	25	# include <err.h>
	26	#endif
4d0dbb8b	27
075d2c07 KZ	28	#ifdef HAVE_SYS_SYSMACROS_H
	29	# include <sys/sysmacros.h> /* for major, minor */
	30	#endif
	31
790119b8 KZ	32	#ifndef LOGIN_NAME_MAX
	33	# define LOGIN_NAME_MAX 256
	34	#endif
	35
7d5976f8 SJ	36	#ifndef NAME_MAX
	37	# define NAME_MAX PATH_MAX
	38	#endif
	39
4d0dbb8b	40	/*
34b0a305 KZ	41	* __GNUC_PREREQ is deprecated in favour of __has_attribute() and
34b0a305 KZ	42	* __has_feature(). The __has macros are supported by clang and gcc>=5.
4d0dbb8b	43	*/
40084d0d KZ	44	#ifndef __GNUC_PREREQ
	45	# if defined __GNUC__ && defined __GNUC_MINOR__
	46	# define __GNUC_PREREQ(maj, min) \
	47	((__GNUC__ << 16) + __GNUC_MINOR__ >= ((maj) << 16) + (min))
	48	# else
	49	# define __GNUC_PREREQ(maj, min) 0
	50	# endif
	51	#endif
	52
4d0dbb8b KZ	53	#ifdef __GNUC__
	54
	55	/* &a[0] degrades to a pointer: a different type from an array */
	56	# define __must_be_array(a) \
bfda68fd	57	UL_BUILD_BUG_ON_ZERO(__builtin_types_compatible_p(__typeof__(a), __typeof__(&a[0])))
4d0dbb8b	58
2a0d2a8e	59	# define ignore_result(x) __extension__ ({ \
c764e1a4	60	__typeof__(x) __dummy __attribute__((__unused__)) = (x); (void) __dummy; \
c25dc28d	61	})
2dd570ec	62
4d0dbb8b KZ	63	#else /* !__GNUC__ */
	64	# define __must_be_array(a) 0
	65	# define __attribute__(_arg_)
2dd570ec	66	# define ignore_result(x) ((void) (x))
4d0dbb8b KZ	67	#endif /* !__GNUC__ */
4d0dbb8b KZ	68
7397f2c1 KZ	69
	70	/* "restrict" keyword fallback */
	71	#if __STDC__ != 1
	72	# define restrict __restrict /* use implementation __ format */
	73	#else
	74	# ifndef __STDC_VERSION__
	75	# define restrict __restrict /* use implementation __ format */
	76	# else
	77	# if __STDC_VERSION__ < 199901L
	78	# define restrict __restrict /* use implementation __ format */
	79	# endif
	80	# endif
	81	#endif
	82
	83
34b0a305 KZ	84	/*
34b0a305 KZ	85	* It evaluates to 1 if the attribute/feature is supported by the current
218b1dd6	86	* compilation target. Fallback for old compilers.
34b0a305 KZ	87	*/
	88	#ifndef __has_attribute
	89	#define __has_attribute(x) 0
	90	#endif
	91
	92	#ifndef __has_feature
	93	#define __has_feature(x) 0
	94	#endif
	95
40084d0d KZ	96	/*
	97	* Function attributes
	98	*/
	99	#ifndef __ul_alloc_size
34b0a305	100	# if (__has_attribute(alloc_size) && __has_attribute(warn_unused_result)) \|\| __GNUC_PREREQ (4, 3)
c9678832	101	# define __ul_alloc_size(s) __attribute__((alloc_size(s), warn_unused_result))
40084d0d KZ	102	# else
	103	# define __ul_alloc_size(s)
	104	# endif
	105	#endif
	106
	107	#ifndef __ul_calloc_size
34b0a305	108	# if (__has_attribute(alloc_size) && __has_attribute(warn_unused_result)) \|\| __GNUC_PREREQ (4, 3)
c9678832	109	# define __ul_calloc_size(n, s) __attribute__((alloc_size(n, s), warn_unused_result))
40084d0d KZ	110	# else
	111	# define __ul_calloc_size(n, s)
	112	# endif
	113	#endif
4d0dbb8b	114
34b0a305	115	#if __has_attribute(returns_nonnull) \|\| __GNUC_PREREQ (4, 9)
f1b327f8 SK	116	# define __ul_returns_nonnull __attribute__((returns_nonnull))
	117	#else
	118	# define __ul_returns_nonnull
	119	#endif
	120
68411ba2 BS	121	/*
68411ba2 BS	122	* Force a compilation error if condition is true, but also produce a
4d0dbb8b	123	* result (of value 0 and type size_t), so the expression can be used
68411ba2	124	* e.g. in a structure initializer (or wherever else comma expressions
4d0dbb8b KZ	125	* aren't permitted).
4d0dbb8b KZ	126	*/
2a0d2a8e	127	#define UL_BUILD_BUG_ON_ZERO(e) __extension__ (sizeof(struct { int:-!!(e); }))
4d0dbb8b KZ	128	#define BUILD_BUG_ON_NULL(e) ((void *)sizeof(struct { int:-!!(e); }))
	129
	130	#ifndef ARRAY_SIZE
	131	# define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]) + __must_be_array(arr))
	132	#endif
	133
	134	#ifndef PATH_MAX
	135	# define PATH_MAX 4096
	136	#endif
	137
	138	#ifndef TRUE
	139	# define TRUE 1
	140	#endif
	141
	142	#ifndef FALSE
	143	# define FALSE 0
	144	#endif
	145
70502c52	146	#ifndef min
2a0d2a8e	147	# define min(x, y) __extension__ ({ \
c764e1a4 SK	148	__typeof__(x) _min1 = (x); \
c764e1a4 SK	149	__typeof__(y) _min2 = (y); \
1cb1641d KZ	150	(void) (&_min1 == &_min2); \
1cb1641d KZ	151	_min1 < _min2 ? _min1 : _min2; })
70502c52	152	#endif
1cb1641d	153
70502c52	154	#ifndef max
2a0d2a8e	155	# define max(x, y) __extension__ ({ \
c764e1a4 SK	156	__typeof__(x) _max1 = (x); \
c764e1a4 SK	157	__typeof__(y) _max2 = (y); \
1cb1641d KZ	158	(void) (&_max1 == &_max2); \
1cb1641d KZ	159	_max1 > _max2 ? _max1 : _max2; })
70502c52	160	#endif
1cb1641d	161
adc21ee1 SA	162	#ifndef abs_diff
	163	# define abs_diff(x, y) __extension__ ({ \
	164	__typeof__(x) _a = (x); \
	165	__typeof__(y) _b = (y); \
	166	(void) (&_a == &_b); \
	167	_a > _b ? _a - _b : _b - _a; })
	168	#endif
	169
19ff8ff7 KZ	170	#ifndef cmp_numbers
	171	# define cmp_numbers(x, y) __extension__ ({ \
	172	__typeof__(x) _a = (x); \
	173	__typeof__(y) _b = (y); \
	174	(void) (&_a == &_b); \
764b697c	175	_a == _b ? 0 : _a > _b ? 1 : -1; })
19ff8ff7 KZ	176	#endif
19ff8ff7 KZ	177
0cfb8c5c KZ	178
	179	#ifndef cmp_timespec
	180	# define cmp_timespec(a, b, CMP) \
	181	(((a)->tv_sec == (b)->tv_sec) \
	182	? ((a)->tv_nsec CMP (b)->tv_nsec) \
	183	: ((a)->tv_sec CMP (b)->tv_sec))
	184	#endif
	185
	186
	187	#ifndef cmp_stat_mtime
	188	# ifdef HAVE_STRUCT_STAT_ST_MTIM_TV_NSEC
	189	# define cmp_stat_mtime(_a, _b, CMP) cmp_timespec(&(_a)->st_mtim, &(_b)->st_mtim, CMP)
	190	# else
	191	# define cmp_stat_mtime(_a, _b, CMP) ((_a)->st_mtime CMP (_b)->st_mtime)
	192	# endif
	193	#endif
	194
	195
5b9df028 DB	196	#ifndef offsetof
	197	#define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER)
	198	#endif
	199
643670d9 KZ	200	#ifndef sizeof_member
	201	#define sizeof_member(TYPE, MEMBER) sizeof(((TYPE *)0)->MEMBER)
	202	#endif
	203
eb06d5d4 KZ	204	/*
	205	* container_of - cast a member of a structure out to the containing structure
	206	* @ptr: the pointer to the member.
	207	* @type: the type of the container struct this is embedded in.
	208	* @member: the name of the member within the struct.
	209	*/
ae278c88	210	#ifndef container_of
eb06d5d4	211	#define container_of(ptr, type, member) __extension__ ({ \
1866fa6a RM	212	const __typeof__( ((type )0)->member ) __mptr = (ptr); \
1866fa6a RM	213	(type )( (char )__mptr - offsetof(type,member) );})
ae278c88	214	#endif
5b9df028	215
4b2b6716	216	#ifndef HAVE_PROGRAM_INVOCATION_SHORT_NAME
	217	# ifdef HAVE___PROGNAME
	218	extern char *__progname;
	219	# define program_invocation_short_name __progname
	220	# else
	221	# ifdef HAVE_GETEXECNAME
4b2b6716	222	# define program_invocation_short_name \
	223	prog_inv_sh_nm_from_file(getexecname(), 0)
	224	# else
	225	# define program_invocation_short_name \
	226	prog_inv_sh_nm_from_file(__FILE__, 1)
	227	# endif
	228	static char prog_inv_sh_nm_buf[256];
	229	static inline char *
	230	prog_inv_sh_nm_from_file(char *f, char stripext)
	231	{
	232	char *t;
	233
	234	if ((t = strrchr(f, '/')) != NULL)
	235	t++;
	236	else
	237	t = f;
	238
	239	strncpy(prog_inv_sh_nm_buf, t, sizeof(prog_inv_sh_nm_buf) - 1);
	240	prog_inv_sh_nm_buf[sizeof(prog_inv_sh_nm_buf) - 1] = '\0';
	241
	242	if (stripext && (t = strrchr(prog_inv_sh_nm_buf, '.')) != NULL)
	243	*t = '\0';
	244
	245	return prog_inv_sh_nm_buf;
	246	}
	247	# endif
	248	#endif
	249
06ceeef8	250
eb76ca98	251	#ifndef HAVE_ERR_H
01085557	252	static inline void __attribute__ ((__format__ (__printf__, 4, 5)))
eb76ca98 FG	253	errmsg(char doexit, int excode, char adderr, const char *fmt, ...)
	254	{
	255	fprintf(stderr, "%s: ", program_invocation_short_name);
	256	if (fmt != NULL) {
	257	va_list argp;
	258	va_start(argp, fmt);
	259	vfprintf(stderr, fmt, argp);
	260	va_end(argp);
	261	if (adderr)
	262	fprintf(stderr, ": ");
	263	}
	264	if (adderr)
960cf573	265	fprintf(stderr, "%m");
eb76ca98 FG	266	fprintf(stderr, "\n");
	267	if (doexit)
	268	exit(excode);
	269	}
	270
	271	#ifndef HAVE_ERR
	272	# define err(E, FMT...) errmsg(1, E, 1, FMT)
	273	#endif
	274
	275	#ifndef HAVE_ERRX
	276	# define errx(E, FMT...) errmsg(1, E, 0, FMT)
	277	#endif
	278
	279	#ifndef HAVE_WARN
	280	# define warn(FMT...) errmsg(0, 0, 1, FMT)
	281	#endif
	282
	283	#ifndef HAVE_WARNX
	284	# define warnx(FMT...) errmsg(0, 0, 0, FMT)
	285	#endif
	286	#endif /* !HAVE_ERR_H */
	287
	288
cb48f21e KZ	289	static inline
	290	__attribute__((__noreturn__))
	291	void __err_oom(const char *file, unsigned int line)
	292	{
	293	err(EXIT_FAILURE, "%s: %u: cannot allocate memory", file, line);
	294	}
	295	#define err_oom() __err_oom(__FILE__, __LINE__)
	296
bb2b071f TW	297	#define err_nosys(exitcode, ...) \
	298	err(errno == ENOSYS ? EXIT_NOTSUPP : exitcode, __VA_ARGS__)
	299
cb48f21e	300
3077b371 KZ	301	/* Don't use inline function to avoid '#include "nls.h"' in c.h
	302	*/
	303	#define errtryhelp(eval) __extension__ ({ \
	304	fprintf(stderr, _("Try '%s --help' for more information.\n"), \
	305	program_invocation_short_name); \
	306	exit(eval); \
	307	})
	308
cf654e1c KZ	309	/* After failed execvp() */
	310	#define EX_EXEC_FAILED 126 /* Program located, but not usable. */
	311	#define EX_EXEC_ENOENT 127 /* Could not find program to exec. */
	312	#define errexec(name) err(errno == ENOENT ? EX_EXEC_ENOENT : EX_EXEC_FAILED, \
	313	_("failed to execute %s"), name)
	314
973af806 KZ	315	static inline __attribute__((const)) int is_power_of_2(unsigned long num)
	316	{
	317	return (num != 0 && ((num & (num - 1)) == 0));
	318	}
	319
5be1c033 FG	320	#ifndef HAVE_LOFF_T
	321	typedef int64_t loff_t;
	322	#endif
	323
8ae8b201 KZ	324	#if !defined(HAVE_DIRFD) \
	325	&& (!defined(HAVE_DECL_DIRFD) \|\| HAVE_DECL_DIRFD == 0) \
	326	&& defined(HAVE_DIR_DD_FD)
d58c47d9 FG	327	#include <dirent.h>
	328	static inline int dirfd(DIR *d)
	329	{
	330	return d->dd_fd;
	331	}
	332	#endif
	333
7cf78990 DB	334	/*
	335	* Fallback defines for old versions of glibc
	336	*/
e9d00e66	337	#include <fcntl.h>
2ffad204 KZ	338
	339	#ifdef O_CLOEXEC
	340	#define UL_CLOEXECSTR "e"
	341	#else
	342	#define UL_CLOEXECSTR ""
	343	#endif
	344
4799c95f KZ	345	#ifndef O_CLOEXEC
	346	#define O_CLOEXEC 0
	347	#endif
973af806	348
f51275ee GJ	349	#ifdef __FreeBSD_kernel__
	350	#ifndef F_DUPFD_CLOEXEC
	351	#define F_DUPFD_CLOEXEC 17 /* Like F_DUPFD, but FD_CLOEXEC is set */
	352	#endif
	353	#endif
	354
2ffad204	355
7cf78990 DB	356	#ifndef AI_ADDRCONFIG
	357	#define AI_ADDRCONFIG 0x0020
	358	#endif
	359
	360	#ifndef IUTF8
	361	#define IUTF8 0040000
	362	#endif
	363
1ee4dff7 SK	364	/*
	365	* MAXHOSTNAMELEN replacement
	366	*/
	367	static inline size_t get_hostname_max(void)
	368	{
	369	long len = sysconf(_SC_HOST_NAME_MAX);
	370
	371	if (0 < len)
	372	return len;
	373
	374	#ifdef MAXHOSTNAMELEN
	375	return MAXHOSTNAMELEN;
	376	#elif HOST_NAME_MAX
	377	return HOST_NAME_MAX;
	378	#endif
	379	return 64;
	380	}
	381
17fc8693 KZ	382
	383	static inline int drop_permissions(void)
	384	{
	385	errno = 0;
	386
17fc8693	387	/* drop GID */
c6d0ea98	388	if (setgid(getgid()) < 0)
17fc8693 KZ	389	goto fail;
	390
	391	/* drop UID */
	392	if (setuid(getuid()) < 0)
	393	goto fail;
	394
	395	return 0;
	396	fail:
	397	return errno ? -errno : -1;
	398	}
	399
2a31396a	400	/*
68411ba2 BS	401	* The usleep function was marked obsolete in POSIX.1-2001 and was removed
	402	* in POSIX.1-2008. It was replaced with nanosleep() that provides more
	403	* advantages (like no interaction with signals and other timer functions).
2a31396a	404	*/
a5bd7939 KZ	405	#include <time.h>
	406
	407	static inline int xusleep(useconds_t usec)
2a31396a	408	{
a5bd7939	409	#ifdef HAVE_NANOSLEEP
2a31396a KZ	410	struct timespec waittime = {
	411	.tv_sec = usec / 1000000L,
	412	.tv_nsec = (usec % 1000000L) * 1000
b33f24b2 WF	413	};
b33f24b2 WF	414	return nanosleep(&waittime, NULL);
a5bd7939 KZ	415	#elif defined(HAVE_USLEEP)
	416	return usleep(usec);
	417	#else
	418	# error "System with usleep() or nanosleep() required!"
2a31396a	419	#endif
a5bd7939	420	}
2a31396a	421
32457b5e KZ	422
	423	#define ul_err_write(_m) ignore_result( write(STDERR_FILENO, _m, strlen(_m)) )
	424
	425	/*
	426	* warn() for signal handlers
	427	*/
	428	static inline void ul_sig_warn(const char *mesg)
	429	{
	430	ul_err_write(program_invocation_short_name);
	431	ul_err_write(": ");
	432	ul_err_write(mesg);
	433	ul_err_write("\n");
	434	}
	435
	436	/*
	437	* err() for signal handlers
	438	*/
	439	static inline void __attribute__((__noreturn__)) ul_sig_err(int excode, const char *mesg)
	440	{
	441	ul_sig_warn(mesg);
	442	_exit(excode);
	443	}
	444
cd7accd4 SK	445	/*
cd7accd4 SK	446	* Constant strings for usage() functions. For more info see
6e2d5a44	447	* Documentation/{howto-usage-function.txt,boilerplate.c}
cd7accd4 SK	448	*/
	449	#define USAGE_HEADER _("\nUsage:\n")
	450	#define USAGE_OPTIONS _("\nOptions:\n")
513bfbef	451	#define USAGE_FUNCTIONS _("\nFunctions:\n")
6e2d5a44	452	#define USAGE_COMMANDS _("\nCommands:\n")
67f938bf	453	#define USAGE_ARGUMENTS _("\nArguments:\n")
c3a4cfc5	454	#define USAGE_COLUMNS _("\nAvailable output columns:\n")
9d1714a3	455	#define USAGE_DEFAULT_COLUMNS _("\nDefault columns:\n")
82b219f7	456	#define USAGE_SEPARATOR "\n"
b1a294c4	457
551b9cd3	458	#define USAGE_OPTSTR_HELP _("display this help")
08e3c9e6	459	#define USAGE_OPTSTR_VERSION _("display version")
b1a294c4	460
f45f3ec3	461	#define USAGE_HELP_OPTIONS(marg_dsc) \
b1a294c4 RM	462	"%-" #marg_dsc "s%s\n" \
	463	"%-" #marg_dsc "s%s\n" \
	464	, " -h, --help", USAGE_OPTSTR_HELP \
f45f3ec3	465	, " -V, --version", USAGE_OPTSTR_VERSION
b1a294c4	466
f1970cc5 KZ	467	#define USAGE_ARG_SEPARATOR "\n"
	468	#define USAGE_ARG_SIZE(_name) \
	469	_(" %s arguments may be followed by the suffixes for\n" \
	470	" GiB, TiB, PiB, EiB, ZiB, and YiB (the \"iB\" is optional)\n"), _name
	471
6f162034	472	#define USAGE_MAN_TAIL(_man) _("\nFor more details see %s.\n"), _man
cd7accd4 SK	473
	474	#define UTIL_LINUX_VERSION _("%s from %s\n"), program_invocation_short_name, PACKAGE_STRING
	475
2c308875 KZ	476	#define print_version(eval) __extension__ ({ \
	477	printf(UTIL_LINUX_VERSION); \
	478	exit(eval); \
	479	})
	480
6895cf92	481	static inline void print_features(const char *features, const char prefix)
beafda18 KZ	482	{
	483	if (features && *features) {
	484	const char **p = features;
	485	while (p && *p) {
6895cf92 KZ	486	if (prefix && p == features)
	487	printf(" (%s ", prefix);
	488	else
	489	fputs(p == features ? " (" : ", ", stdout);
beafda18 KZ	490	fputs(*p++, stdout);
	491	}
	492	fputc(')', stdout);
	493	}
	494	}
	495
	496	#define UTIL_LINUX_VERSION_NOBREAK _("%s from %s"), program_invocation_short_name, PACKAGE_STRING
	497
	498	#define print_version_with_features(eval, features) __extension__ ({ \
	499	printf(UTIL_LINUX_VERSION_NOBREAK); \
6895cf92	500	print_features(features, _("features:")); \
beafda18 KZ	501	fputc('\n', stdout); \
	502	exit(eval); \
	503	})
	504
9199f5cd KZ	505	/*
	506	* seek stuff
	507	*/
	508	#ifndef SEEK_DATA
	509	# define SEEK_DATA 3
	510	#endif
	511	#ifndef SEEK_HOLE
	512	# define SEEK_HOLE 4
	513	#endif
	514
ff1aaf99 SK	515
	516	/*
	517	* Macros to convert #define'itions to strings, for example
	518	* #define XYXXY 42
	519	* printf ("%s=%s\n", stringify(XYXXY), stringify_value(XYXXY));
	520	*/
	521	#define stringify_value(s) stringify(s)
	522	#define stringify(s) #s
	523
c40b3cd0 FS	524	/* Detect if we're compiled with Address Sanitizer
	525	* - gcc (__SANITIZE_ADDRESS__)
	526	* - clang (__has_feature(address_sanitizer))
	527	*/
	528	#if !defined(HAS_FEATURE_ADDRESS_SANITIZER)
	529	# ifdef __SANITIZE_ADDRESS__
	530	# define HAS_FEATURE_ADDRESS_SANITIZER 1
	531	# elif defined(__has_feature)
	532	# if __has_feature(address_sanitizer)
	533	# define HAS_FEATURE_ADDRESS_SANITIZER 1
	534	# endif
	535	# endif
	536	# if !defined(HAS_FEATURE_ADDRESS_SANITIZER)
	537	# define HAS_FEATURE_ADDRESS_SANITIZER 0
	538	# endif
	539	#endif
	540
d763c230 SK	541	/*
	542	* UL_ASAN_BLACKLIST is a macro to tell AddressSanitizer (a compile-time
	543	* instrumentation shipped with Clang and GCC) to not instrument the
	544	* annotated function. Furthermore, it will prevent the compiler from
	545	* inlining the function because inlining currently breaks the blacklisting
	546	* mechanism of AddressSanitizer.
	547	*/
34b0a305 KZ	548	#if __has_feature(address_sanitizer) && __has_attribute(no_sanitize_memory) && __has_attribute(no_sanitize_address)
34b0a305 KZ	549	# define UL_ASAN_BLACKLIST __attribute__((noinline)) __attribute__((no_sanitize_memory)) __attribute__((no_sanitize_address))
d763c230 SK	550	#else
	551	# define UL_ASAN_BLACKLIST /* nothing */
	552	#endif
	553
f7ac9e71 KZ	554	/*
	555	* Note that sysconf(_SC_GETPW_R_SIZE_MAX) returns initial suggested size for
	556	* pwd buffer and in some cases it is not large enough. See POSIX and
	557	* getpwnam_r man page for more details.
	558	*/
	559	#define UL_GETPW_BUFSIZ (16 * 1024)
	560
40733239 RM	561	/*
	562	* Darwin or other BSDs may only have MAP_ANON. To get it on Darwin we must
	563	* define _DARWIN_C_SOURCE before including sys/mman.h. We do this in config.h.
	564	*/
	565	#if !defined MAP_ANONYMOUS && defined MAP_ANON
	566	# define MAP_ANONYMOUS (MAP_ANON)
	567	#endif
	568
1ef0be3a	569	#define SINT_MAX(t) (((t)1 << (sizeof(t) * 8 - 2)) - (t)1 + ((t)1 << (sizeof(t) * 8 - 2)))
550d32c4	570
4d0dbb8b	571	#endif /* UTIL_LINUX_C_H */