// SPDX-License-Identifier: GPL-2.0

  /*
   *  linux/tools/lib/string.c
   *
   *  Copied from linux/lib/string.c, where it is:
   *
   *  Copyright (C) 1991, 1992  Linus Torvalds
   *
   *  More specifically, the first copied function was strtobool, which
   *  was introduced by:
   *
   *  d0f1fed29e6e ("Add a strtobool function matching semantics of existing in kernel equivalents")
   *  Author: Jonathan Cameron <jic23@cam.ac.uk>
   */

  #include <stdlib.h>
  #include <string.h>

  #include <errno.h>

  #include <linux/string.h>

  #include <linux/ctype.h>

  #include <linux/compiler.h>

  
  /**
   * memdup - duplicate region of memory
   *
   * @src: memory region to duplicate
   * @len: memory region length
   */
  void *memdup(const void *src, size_t len)
  {
  	void *p = malloc(len);
  
  	if (p)
  		memcpy(p, src, len);
  
  	return p;
  }

  
  /**
   * strtobool - convert common user inputs into boolean values
   * @s: input string
   * @res: result
   *

   * This routine returns 0 iff the first character is one of 'Yy1Nn0', or
   * [oO][NnFf] for "on" and "off". Otherwise it will return -EINVAL.  Value
   * pointed to by res is updated upon finding a match.

   */
  int strtobool(const char *s, bool *res)
  {

  	if (!s)
  		return -EINVAL;

  	switch (s[0]) {
  	case 'y':
  	case 'Y':
  	case '1':
  		*res = true;

  		return 0;

  	case 'n':
  	case 'N':
  	case '0':
  		*res = false;

  		return 0;
  	case 'o':
  	case 'O':
  		switch (s[1]) {
  		case 'n':
  		case 'N':
  			*res = true;
  			return 0;
  		case 'f':
  		case 'F':
  			*res = false;
  			return 0;
  		default:
  			break;
  		}

  	default:

  		break;

  	}

  
  	return -EINVAL;

  }

  
  /**
   * strlcpy - Copy a C-string into a sized buffer
   * @dest: Where to copy the string to
   * @src: Where to copy the string from
   * @size: size of destination buffer
   *
   * Compatible with *BSD: the result is always a valid
   * NUL-terminated string that fits in the buffer (unless,
   * of course, the buffer size is zero). It does not pad
   * out the result like strncpy() does.
   *
   * If libc has strlcpy() then that version will override this
   * implementation:
   */

  #ifdef __clang__
  #pragma clang diagnostic push
  #pragma clang diagnostic ignored "-Wignored-attributes"
  #endif

  size_t __weak strlcpy(char *dest, const char *src, size_t size)
  {
  	size_t ret = strlen(src);
  
  	if (size) {
  		size_t len = (ret >= size) ? size - 1 : ret;
  		memcpy(dest, src, len);
  		dest[len] = '\0';
  	}
  	return ret;
  }

  #ifdef __clang__
  #pragma clang diagnostic pop
  #endif

  
  /**
   * skip_spaces - Removes leading whitespace from @str.
   * @str: The string to be stripped.
   *
   * Returns a pointer to the first non-whitespace character in @str.
   */
  char *skip_spaces(const char *str)
  {
  	while (isspace(*str))
  		++str;
  	return (char *)str;
  }

  
  /**
   * strim - Removes leading and trailing whitespace from @s.
   * @s: The string to be stripped.
   *
   * Note that the first trailing whitespace is replaced with a %NUL-terminator
   * in the given string @s. Returns a pointer to the first non-whitespace
   * character in @s.
   */
  char *strim(char *s)
  {
  	size_t size;
  	char *end;
  
  	size = strlen(s);
  	if (!size)
  		return s;
  
  	end = s + size - 1;
  	while (end >= s && isspace(*end))
  		end--;
  	*(end + 1) = '\0';
  
  	return skip_spaces(s);
  }

  
  /**
   * strreplace - Replace all occurrences of character in string.
   * @s: The string to operate on.
   * @old: The character being replaced.
   * @new: The character @old is replaced with.
   *
   * Returns pointer to the nul byte at the end of @s.
   */
  char *strreplace(char *s, char old, char new)
  {
  	for (; *s; ++s)
  		if (*s == old)
  			*s = new;
  	return s;
  }