/* SPDX-License-Identifier: GPL-2.0-only */

#ifndef _LINUX_STRING_H_
#define _LINUX_STRING_H_

#include <linux/types.h>	/* for size_t */
#include <linux/stddef.h>	/* for NULL */
#include <linux/overflow.h>	/* for array_size */

#ifdef __cplusplus
extern "C" {
#endif

extern char * strpbrk(const char *,const char *);
extern char * strsep(char **,const char *);
extern __kernel_size_t strspn(const char *,const char *);


#define strchr(s, c) ({ \
	(typeof(&(s)[0]))(_strchr((s), c)); \
	})

#define strrchr(s, c) ({ \
	(typeof(&(s)[0]))(_strrchr((s), c)); \
	})

#define strstr(s1, s2) ({ \
	(typeof(&(s1)[0]))(_strstr((s1), (s2))); \
	})

#ifndef __HAVE_ARCH_STRCHRNUL
extern char * strchrnul(const char *,int);
#endif

/*
 * Include machine specific inline routines
 */
#include <asm/string.h>

#ifndef __HAVE_ARCH_STRCPY
extern char * strcpy(char *,const char *);
#endif
#ifndef __HAVE_ARCH_STRNCPY
extern char * strncpy(char *,const char *, __kernel_size_t);
#endif
#ifndef __HAVE_ARCH_STRLCPY
size_t strlcpy(char *, const char *, size_t);
#endif
#ifndef __HAVE_ARCH_STRSCPY
ssize_t strscpy(char *, const char *, size_t);
#endif
#ifndef __HAVE_ARCH_STRCAT
extern char * strcat(char *, const char *);
#endif
#ifndef __HAVE_ARCH_STRNCAT
extern char * strncat(char *, const char *, __kernel_size_t);
#endif
#ifndef __HAVE_ARCH_STRCMP
extern int strcmp(const char *,const char *);
#endif
#ifndef __HAVE_ARCH_STRNCMP
extern int strncmp(const char *,const char *,__kernel_size_t);
#endif
#ifndef __HAVE_ARCH_STRCASECMP
extern int strcasecmp(const char *s1, const char *s2);
#endif
#ifndef __HAVE_ARCH_STRNCASECMP
extern int strncasecmp(const char *s1, const char *s2, size_t n);
#endif
#ifndef __HAVE_ARCH_STRCHR
extern char * _strchr(const char *,int);
#endif
#ifndef __HAVE_ARCH_STRRCHR
extern char * _strrchr(const char *,int);
#endif
#ifndef __HAVE_ARCH_STRSTR
extern char * _strstr(const char *,const char *);
#endif
#ifndef __HAVE_ARCH_STRLEN
extern __kernel_size_t strlen(const char *);
#endif
#ifndef __HAVE_ARCH_STRNLEN
extern __kernel_size_t strnlen(const char *,__kernel_size_t);
#endif
#ifndef __HAVE_ARCH_STRDUP
extern char * strdup(const char *);
#endif
#ifndef __HAVE_ARCH_STRNDUP
extern char *strndup(const char *, size_t);
#endif
#ifndef __HAVE_ARCH_STRSWAB
extern char * strswab(const char *);
#endif

#ifndef __HAVE_ARCH_MEMSET
extern void * memset(void *,int,__kernel_size_t);
#endif
#ifndef __HAVE_ARCH_MEMCPY
extern void * memcpy(void *,const void *,__kernel_size_t);
#endif
#ifndef __HAVE_ARCH_MEMMOVE
extern void * memmove(void *,const void *,__kernel_size_t);
#endif
#ifndef __HAVE_ARCH_MEMSCAN
extern void * memscan(void *,int,__kernel_size_t);
#endif
#ifndef __HAVE_ARCH_MEMCMP
extern int memcmp(const void *,const void *,__kernel_size_t);
#endif
#ifndef __HAVE_ARCH_MEMCHR
extern void * memchr(const void *,int,__kernel_size_t);
#endif
extern char * skip_spaces(const char *);

extern char *strim(char *);

void *memchr_inv(const void *start, int c, size_t bytes);
char *strreplace(char *str, char old, char new);

/**
 * memzero_explicit - Fill a region of memory (e.g. sensitive
 *		      keying data) with 0s.
 * @s: Pointer to the start of the area.
 * @count: The size of the area.
 *
 * Note: usually using memset() is just fine (!), but in cases
 * where clearing out _local_ data at the end of a scope is
 * necessary, memzero_explicit() should be used instead in
 * order to prevent the compiler from optimising away zeroing.
 *
 * memzero_explicit() doesn't need an arch-specific version as
 * it just invokes the one of memset() implicitly.
 */
static inline void memzero_explicit(void *s, size_t count)
{
	memset(s, 0, count);
	barrier_data(s);
}

/**
 * kbasename - return the last part of a pathname.
 *
 * @path: path to extract the filename from.
 */
static inline const char *kbasename(const char *path)
{
	const char *tail = strrchr(path, '/');
	return tail ? tail + 1 : path;
}


#ifdef __cplusplus
}
#endif

void *memdup(const void *, size_t);

#define memdup_array(arr, count) memdup(arr, array_size(count, sizeof(*arr)));

static inline void *kmemdup(const void *src, size_t len, gfp_t gfp)
{
	return memdup(src, len);
}

extern int kstrtobool(const char *s, bool *res);

int match_string(const char * const *array, size_t n, const char *string);

/**
 * strstarts - does @str start with @prefix?
 * @str: string to examine
 * @prefix: prefix to look for.
 */
static inline bool strstarts(const char *str, const char *prefix)
{
	return strncmp(str, prefix, strlen(prefix)) == 0;
}

/**
 * str_has_prefix - Test if a string has a given prefix
 * @str: The string to test
 * @prefix: The string to see if @str starts with
 *
 * A common way to test a prefix of a string is to do:
 *  strncmp(str, prefix, sizeof(prefix) - 1)
 *
 * But this can lead to bugs due to typos, or if prefix is a pointer
 * and not a constant. Instead use str_has_prefix().
 *
 * Returns:
 * * strlen(@prefix) if @str starts with @prefix
 * * 0 if @str does not start with @prefix
 */
static __always_inline size_t str_has_prefix(const char *str, const char *prefix)
{
	size_t len = strlen(prefix);
	return strncmp(str, prefix, len) == 0 ? len : 0;
}

#endif /* _LINUX_STRING_H_ */