/*****************************************************************************

Copyright (c) 1994, 2014, Oracle and/or its affiliates. All Rights Reserved.

This program is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free Software
Foundation; version 2 of the License.

This program is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with
this program; if not, write to the Free Software Foundation, Inc.,
51 Franklin Street, Suite 500, Boston, MA 02110-1335 USA

*****************************************************************************/

/*******************************************************************//**
@file include/ut0mem.ic
Memory primitives

Created 5/30/1994 Heikki Tuuri
************************************************************************/

#include "ut0byte.h"
#include "mach0data.h"

/** Wrapper for memcpy(3).  Copy memory area when the source and
target are not overlapping.
@param[in,out]	dest	copy to
@param[in]	src	copy from
@param[in]	n	number of bytes to copy
@return dest */
UNIV_INLINE
void*
ut_memcpy(void* dest, const void* src, ulint n)
{
	return(memcpy(dest, src, n));
}

/** Wrapper for memmove(3).  Copy memory area when the source and
target are overlapping.
@param[in,out]	dest	Move to
@param[in]	src	Move from
@param[in]	n	number of bytes to move
@return dest */
UNIV_INLINE
void*
ut_memmove(void* dest, const void* src, ulint n)
{
	return(memmove(dest, src, n));
}

/** Wrapper for memcmp(3).  Compare memory areas.
@param[in]	str1	first memory block to compare
@param[in]	str2	second memory block to compare
@param[in]	n	number of bytes to compare
@return negative, 0, or positive if str1 is smaller, equal,
		or greater than str2, respectively. */
UNIV_INLINE
int
ut_memcmp(const void* str1, const void* str2, ulint n)
{
	return(memcmp(str1, str2, n));
}

/** Wrapper for strcpy(3).  Copy a NUL-terminated string.
@param[in,out]	dest	Destination to copy to
@param[in]	src	Source to copy from
@return dest */
UNIV_INLINE
char*
ut_strcpy(char* dest, const char* src)
{
	return(strcpy(dest, src));
}

/** Wrapper for strlen(3).  Determine the length of a NUL-terminated string.
@param[in]	str	string
@return length of the string in bytes, excluding the terminating NUL */
UNIV_INLINE
ulint
ut_strlen(const char* str)
{
	return(strlen(str));
}

/** Wrapper for strcmp(3).  Compare NUL-terminated strings.
@param[in]	str1	first string to compare
@param[in]	str2	second string to compare
@return negative, 0, or positive if str1 is smaller, equal,
		or greater than str2, respectively. */
UNIV_INLINE
int
ut_strcmp(const char* str1, const char* str2)
{
	return(strcmp(str1, str2));
}

/**********************************************************************//**
Converts a raw binary data to a NUL-terminated hex string. The output is
truncated if there is not enough space in "hex", make sure "hex_size" is at
least (2 * raw_size + 1) if you do not want this to happen. Returns the
actual number of characters written to "hex" (including the NUL).
@return number of chars written */
UNIV_INLINE
ulint
ut_raw_to_hex(
/*==========*/
	const void*	raw,		/*!< in: raw data */
	ulint		raw_size,	/*!< in: "raw" length in bytes */
	char*		hex,		/*!< out: hex string */
	ulint		hex_size)	/*!< in: "hex" size in bytes */
{

#ifdef WORDS_BIGENDIAN

#define MK_UINT16(a, b) (((uint16) (a)) << 8 | (uint16) (b))

#define UINT16_GET_A(u)	((unsigned char) ((u) >> 8))
#define UINT16_GET_B(u)	((unsigned char) ((u) & 0xFF))

#else /* WORDS_BIGENDIAN */

#define MK_UINT16(a, b) (((uint16) (b)) << 8 | (uint16) (a))

#define UINT16_GET_A(u)	((unsigned char) ((u) & 0xFF))
#define UINT16_GET_B(u)	((unsigned char) ((u) >> 8))

#endif /* WORDS_BIGENDIAN */

#define MK_ALL_UINT16_WITH_A(a)	\
	MK_UINT16(a, '0'),	\
	MK_UINT16(a, '1'),	\
	MK_UINT16(a, '2'),	\
	MK_UINT16(a, '3'),	\
	MK_UINT16(a, '4'),	\
	MK_UINT16(a, '5'),	\
	MK_UINT16(a, '6'),	\
	MK_UINT16(a, '7'),	\
	MK_UINT16(a, '8'),	\
	MK_UINT16(a, '9'),	\
	MK_UINT16(a, 'A'),	\
	MK_UINT16(a, 'B'),	\
	MK_UINT16(a, 'C'),	\
	MK_UINT16(a, 'D'),	\
	MK_UINT16(a, 'E'),	\
	MK_UINT16(a, 'F')

	static const uint16	hex_map[256] = {
		MK_ALL_UINT16_WITH_A('0'),
		MK_ALL_UINT16_WITH_A('1'),
		MK_ALL_UINT16_WITH_A('2'),
		MK_ALL_UINT16_WITH_A('3'),
		MK_ALL_UINT16_WITH_A('4'),
		MK_ALL_UINT16_WITH_A('5'),
		MK_ALL_UINT16_WITH_A('6'),
		MK_ALL_UINT16_WITH_A('7'),
		MK_ALL_UINT16_WITH_A('8'),
		MK_ALL_UINT16_WITH_A('9'),
		MK_ALL_UINT16_WITH_A('A'),
		MK_ALL_UINT16_WITH_A('B'),
		MK_ALL_UINT16_WITH_A('C'),
		MK_ALL_UINT16_WITH_A('D'),
		MK_ALL_UINT16_WITH_A('E'),
		MK_ALL_UINT16_WITH_A('F')
	};
	const unsigned char*	rawc;
	ulint			read_bytes;
	ulint			write_bytes;
	ulint			i;

	rawc = (const unsigned char*) raw;

	if (hex_size == 0) {

		return(0);
	}

	if (hex_size <= 2 * raw_size) {

		read_bytes = hex_size / 2;
		write_bytes = hex_size;
	} else {

		read_bytes = raw_size;
		write_bytes = 2 * raw_size + 1;
	}

#define LOOP_READ_BYTES(ASSIGN)			\
	for (i = 0; i < read_bytes; i++) {	\
		ASSIGN;				\
		hex += 2;			\
		rawc++;				\
	}

	if (ut_align_offset(hex, 2) == 0) {

		LOOP_READ_BYTES(
			*(uint16*) hex = hex_map[*rawc]
		);
	} else {

		LOOP_READ_BYTES(
			*hex       = UINT16_GET_A(hex_map[*rawc]);
			*(hex + 1) = UINT16_GET_B(hex_map[*rawc])
		);
	}

	if (hex_size <= 2 * raw_size && hex_size % 2 == 0) {

		hex--;
	}

	*hex = '\0';

	return(write_bytes);
}

/*******************************************************************//**
Adds single quotes to the start and end of string and escapes any quotes
by doubling them. Returns the number of bytes that were written to "buf"
(including the terminating NUL). If buf_size is too small then the
trailing bytes from "str" are discarded.
@return number of bytes that were written */
UNIV_INLINE
ulint
ut_str_sql_format(
/*==============*/
	const char*	str,		/*!< in: string */
	ulint		str_len,	/*!< in: string length in bytes */
	char*		buf,		/*!< out: output buffer */
	ulint		buf_size)	/*!< in: output buffer size
					in bytes */
{
	ulint	str_i;
	ulint	buf_i;

	buf_i = 0;

	switch (buf_size) {
	case 3:

		if (str_len == 0) {

			buf[buf_i] = '\'';
			buf_i++;
			buf[buf_i] = '\'';
			buf_i++;
		}
		/* FALLTHROUGH */
	case 2:
	case 1:

		buf[buf_i] = '\0';
		buf_i++;
		/* FALLTHROUGH */
	case 0:

		return(buf_i);
	}

	/* buf_size >= 4 */

	buf[0] = '\'';
	buf_i = 1;

	for (str_i = 0; str_i < str_len; str_i++) {

		char	ch;

		if (buf_size - buf_i == 2) {

			break;
		}

		ch = str[str_i];

		switch (ch) {
		case '\0':

			if (buf_size - buf_i < 4) {

				goto func_exit;
			}
			buf[buf_i] = '\\';
			buf_i++;
			buf[buf_i] = '0';
			buf_i++;
			break;
		case '\'':
		case '\\':

			if (buf_size - buf_i < 4) {

				goto func_exit;
			}
			buf[buf_i] = ch;
			buf_i++;
			/* FALLTHROUGH */
		default:

			buf[buf_i] = ch;
			buf_i++;
		}
	}

func_exit:

	buf[buf_i] = '\'';
	buf_i++;
	buf[buf_i] = '\0';
	buf_i++;

	return(buf_i);
}