utils.h

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Author : Michael Forney
Date : 2019-06-04 14:01:02
Hash : 9d58bbd4
Message : Use bitwise test instead of popcount to check if one bit is set We don't need to determine the total number of bits set to determine if exactly one is set. Additionally, on x86_64 without any -march=* flag, __builtin_popcount will get compiled to a function call to the compiler runtime (on gcc), or a long sequence of bit operations (on clang). Signed-off-by: Michael Forney <mforney@mforney.org>
src/utils.h
/*
 * Copyright © 2012 Ran Benita <ran234@gmail.com>
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice (including the next
 * paragraph) shall be included in all copies or substantial portions of the
 * Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 * DEALINGS IN THE SOFTWARE.
 */

#ifndef UTILS_H
#define UTILS_H 1

#include <errno.h>
#include <inttypes.h>
#include <stdbool.h>
#include <stdio.h>
#include <string.h>

#include "darray.h"

/*
 * We sometimes malloc strings and then expose them as const char*'s. This
 * macro is used when we free these strings in order to avoid -Wcast-qual
 * errors.
 */
#define UNCONSTIFY(const_ptr)  ((void *) (uintptr_t) (const_ptr))

#define STATIC_ASSERT(expr, message) do { \
    switch (0) { case 0: case (expr): ; } \
} while (0)

char
to_lower(char c);

int
istrcmp(const char *a, const char *b);

int
istrncmp(const char *a, const char *b, size_t n);

static inline bool
streq(const char *s1, const char *s2)
{
    return strcmp(s1, s2) == 0;
}

static inline bool
streq_not_null(const char *s1, const char *s2)
{
    if (!s1 || !s2)
        return false;
    return streq(s1, s2);
}

static inline bool
istreq(const char *s1, const char *s2)
{
    return istrcmp(s1, s2) == 0;
}

static inline bool
istreq_prefix(const char *s1, const char *s2)
{
    return istrncmp(s1, s2, strlen(s1)) == 0;
}

static inline char *
strdup_safe(const char *s)
{
    return s ? strdup(s) : NULL;
}

static inline size_t
strlen_safe(const char *s)
{
    return s ? strlen(s) : 0;
}

static inline bool
isempty(const char *s)
{
    return s == NULL || s[0] == '\0';
}

static inline const char *
strnull(const char *s)
{
    return s ? s : "(null)";
}

static inline const char *
strempty(const char *s)
{
    return s ? s : "";
}

static inline void *
memdup(const void *mem, size_t nmemb, size_t size)
{
    void *p = calloc(nmemb, size);
    if (p)
        memcpy(p, mem, nmemb * size);
    return p;
}

static inline int
min(int misc, int other)
{
    return (misc < other) ? misc : other;
}

static inline int
max(int misc, int other)
{
    return (misc > other) ? misc : other;
}

/* ctype.h is locale-dependent and has other oddities. */
static inline bool
is_space(char ch)
{
    return ch == ' ' || (ch >= '\t' && ch <= '\r');
}

static inline bool
is_alpha(char ch)
{
    return (ch >= 'a' && ch <= 'z') || (ch >= 'A' && ch <= 'Z');
}

static inline bool
is_digit(char ch)
{
    return ch >= '0' && ch <= '9';
}

static inline bool
is_alnum(char ch)
{
    return is_alpha(ch) || is_digit(ch);
}

static inline bool
is_xdigit(char ch)
{
    return
        (ch >= '0' && ch <= '9') ||
        (ch >= 'a' && ch <= 'f') ||
        (ch >= 'A' && ch <= 'F');
}

static inline bool
is_graph(char ch)
{
    /* See table in ascii(7). */
    return ch >= '!' && ch <= '~';
}

/*
 * Return the bit position of the most significant bit.
 * Note: this is 1-based! It's more useful this way, and returns 0 when
 * mask is all 0s.
 */
static inline unsigned
msb_pos(uint32_t mask)
{
    unsigned pos = 0;
    while (mask) {
        pos++;
        mask >>= 1u;
    }
    return pos;
}

static inline int
one_bit_set(uint32_t x)
{
    return x && (x & (x - 1)) == 0;
}

bool
map_file(FILE *file, char **string_out, size_t *size_out);

void
unmap_file(char *string, size_t size);

#define ARRAY_SIZE(arr) ((sizeof(arr) / sizeof(*(arr))))

#define MIN(a, b) ((a) < (b) ? (a) : (b))
#define MIN3(a, b, c) MIN(MIN((a), (b)), (c))
#define MAX(a, b) ((a) > (b) ? (a) : (b))
#define MAX3(a, b, c) MAX(MAX((a), (b)), (c))

/* Round up @a so it's divisible by @b. */
#define ROUNDUP(a, b) (((a) + (b) - 1) / (b) * (b))

#if defined(HAVE_SECURE_GETENV)
# define secure_getenv secure_getenv
#elif defined(HAVE___SECURE_GETENV)
# define secure_getenv __secure_getenv
#else
# define secure_getenv getenv
#endif

#if defined(HAVE___BUILTIN_EXPECT)
# define likely(x)   __builtin_expect(!!(x), 1)
# define unlikely(x) __builtin_expect(!!(x), 0)
#else
# define likely(x)   (x)
# define unlikely(x) (x)
#endif

/* Compiler Attributes */

#if defined(__GNUC__) && (__GNUC__ >= 4) && !defined(__CYGWIN__)
# define XKB_EXPORT      __attribute__((visibility("default")))
#elif defined(__SUNPRO_C) && (__SUNPRO_C >= 0x550)
# define XKB_EXPORT      __global
#else /* not gcc >= 4 and not Sun Studio >= 8 */
# define XKB_EXPORT
#endif

#if defined(__GNUC__) && ((__GNUC__ * 100 + __GNUC_MINOR__) >= 203)
# define ATTR_PRINTF(x,y) __attribute__((__format__(__printf__, x, y)))
#else /* not gcc >= 2.3 */
# define ATTR_PRINTF(x,y)
#endif

#if (defined(__GNUC__) && ((__GNUC__ * 100 + __GNUC_MINOR__) >= 205)) \
    || (defined(__SUNPRO_C) && (__SUNPRO_C >= 0x590))
# define ATTR_NORETURN __attribute__((__noreturn__))
#else
# define ATTR_NORETURN
#endif /* GNUC  */

#if (defined(__GNUC__) && (__GNUC__ * 100 + __GNUC_MINOR__) >= 296)
#define ATTR_MALLOC  __attribute__((__malloc__))
#else
#define ATTR_MALLOC
#endif

#if defined(__GNUC__) && (__GNUC__ >= 4)
# define ATTR_NULL_SENTINEL __attribute__((__sentinel__))
#else
# define ATTR_NULL_SENTINEL
#endif /* GNUC >= 4 */

#if (defined(__GNUC__) && (__GNUC__ * 100 + __GNUC_MINOR__) >= 295)
#define ATTR_PACKED  __attribute__((__packed__))
#else
#define ATTR_PACKED
#endif

#endif /* UTILS_H */
kc3-lang/libxkbcommon/src/utils.h

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kc3-lang/libxkbcommon /src/utils.h
