Conversion
[LibTDS API]

Conversions between datatypes. More...

Defines
#define	binary_to_result(data, len, cr)   binary_to_result(desttype, data, len, cr)
#define	CASE_ALL_BINARY   SYBBINARY: case SYBVARBINARY: case SYBIMAGE: case XSYBBINARY: case XSYBVARBINARY: case TDS_CONVERT_BINARY
#define	CASE_ALL_CHAR   SYBCHAR: case SYBVARCHAR: case SYBTEXT: case XSYBCHAR: case XSYBVARCHAR
#define	is_monthname(s)   (store_monthname(s, NULL) >= 0)
#define	string_to_result(s, cr)   string_to_result(desttype, s, cr)
Functions
static TDS_INT	binary_to_result (int desttype, const void *data, size_t len, CONV_RESULT *cr)
	Copy binary data to to result and return len or TDS_CONVERT_NOMEM.
static int	is_alphabetic (const char *)
static int	is_ampm (const char *)
static int	is_dd_mon_yyyy (char *t)
static int	is_numeric (const char *)
static int	is_numeric_dateformat (const char *)
static int	is_timeformat (const char *)
static int	store_dd_mon_yyy_date (char *datestr, struct tds_time *t)
static int	store_hour (const char *, const char *, struct tds_time *)
static int	store_mday (const char *, struct tds_time *)
static int	store_monthname (const char *datestr, struct tds_time *t)
	Test if a string is a month name and store correct month number.
static int	store_numeric_date (const char *, struct tds_time *)
static int	store_time (const char *, struct tds_time *)
static int	store_year (int, struct tds_time *)
static int	store_yymmdd_date (const char *, struct tds_time *)
static int	string_to_datetime (const char *datestr, int desttype, CONV_RESULT *cr)
static TDS_INT	string_to_int (const char *buf, const char *pend, TDS_INT *res)
	convert a number in string to TDS_INT
static TDS_INT	string_to_int8 (const char *buf, const char *pend, TDS_INT8 *res)
	convert a number in string to TDS_INT8
static int	string_to_numeric (const char *instr, const char *pend, CONV_RESULT *cr)
	convert a number in string to a TDSNUMERIC
static TDS_INT	string_to_result (int desttype, const char *s, CONV_RESULT *cr)
	Copy a terminated string to result and return len or TDS_CONVERT_NOMEM.
static int	stringz_to_numeric (const char *instr, CONV_RESULT *cr)
	convert a zero terminated string to NUMERIC
TDS_INT	tds_char2hex (TDS_CHAR *dest, TDS_UINT destlen, const TDS_CHAR *src, TDS_UINT srclen)
TDS_INT	tds_convert (const TDSCONTEXT *tds_ctx, int srctype, const TDS_CHAR *src, TDS_UINT srclen, int desttype, CONV_RESULT *cr)
	tds_convert convert a type to another.
static TDS_INT	tds_convert_binary (int srctype, const TDS_UCHAR *src, TDS_INT srclen, int desttype, CONV_RESULT *cr)
static TDS_INT	tds_convert_bit (int srctype, const TDS_CHAR *src, int desttype, CONV_RESULT *cr)
static TDS_INT	tds_convert_char (int srctype, const TDS_CHAR *src, TDS_UINT srclen, int desttype, CONV_RESULT *cr)
static TDS_INT	tds_convert_datetime (const TDSCONTEXT *tds_ctx, int srctype, const TDS_CHAR *src, int desttype, CONV_RESULT *cr)
static TDS_INT	tds_convert_datetime4 (const TDSCONTEXT *tds_ctx, int srctype, const TDS_CHAR *src, int desttype, CONV_RESULT *cr)
static TDS_INT	tds_convert_flt8 (int srctype, const TDS_CHAR *src, int desttype, CONV_RESULT *cr)
static TDS_INT	tds_convert_int1 (int srctype, const TDS_CHAR *src, int desttype, CONV_RESULT *cr)
static TDS_INT	tds_convert_int2 (int srctype, const TDS_CHAR *src, int desttype, CONV_RESULT *cr)
static TDS_INT	tds_convert_int4 (int srctype, const TDS_CHAR *src, int desttype, CONV_RESULT *cr)
static TDS_INT	tds_convert_int8 (int srctype, const TDS_CHAR *src, int desttype, CONV_RESULT *cr)
static TDS_INT	tds_convert_money (int srctype, const TDS_CHAR *src, int desttype, CONV_RESULT *cr)
static TDS_INT	tds_convert_money4 (int srctype, const TDS_CHAR *src, int srclen, int desttype, CONV_RESULT *cr)
static TDS_INT	tds_convert_numeric (int srctype, const TDS_NUMERIC *src, TDS_INT srclen, int desttype, CONV_RESULT *cr)
static TDS_INT	tds_convert_real (int srctype, const TDS_CHAR *src, int desttype, CONV_RESULT *cr)
static TDS_INT	tds_convert_unique (int srctype, const TDS_CHAR *src, TDS_INT srclen, int desttype, CONV_RESULT *cr)
TDS_INT	tds_datecrack (TDS_INT datetype, const void *di, TDSDATEREC *dr)
	Convert from db date format to a structured date format.
TDS_INT	tds_get_null_type (int srctype)
	Get same type but nullable.
size_t	tds_strftime (char *buf, size_t maxsize, const char *format, const TDSDATEREC *dr)
	format a date string according to an "extended" strftime(3) formatting definition.
unsigned char	tds_willconvert (int srctype, int desttype)
	Test if a conversion is possible.
Variables
const char	tds_hex_digits [16] = "0123456789abcdef"

---

Detailed Description

Conversions between datatypes.

Supports, for example, dbconvert().

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Function Documentation

static int store_monthname	(	const char *	datestr,
		struct tds_time *	t
	)			[static]

Test if a string is a month name and store correct month number.

Returns:

month number (0-11) or -1 if not match

Parameters:

	datestr	string to check
	t	where to store month (if NULL no store is done)

static TDS_INT string_to_int	(	const char *	buf,
		const char *	pend,
		TDS_INT *	res
	)			[static]

convert a number in string to TDS_INT

Returns:

TDS_CONVERT_* or failure code on error

Remarks:

Sybase's char->int conversion tolerates embedded blanks, such that "convert( int, ' - 13 ' )" works. If we find blanks, we copy the string to a temporary buffer, skipping the blanks. We return the results of atoi() with a clean string.

n.b. it is possible to embed all sorts of non-printable characters, but we only check for spaces. at this time, no one on the project has tested anything else.

static TDS_INT string_to_int8	(	const char *	buf,
		const char *	pend,
		TDS_INT8 *	res
	)			[static]

convert a number in string to TDS_INT8

Returns:

TDS_CONVERT_* or failure code on error

static int string_to_numeric	(	const char *	instr,
		const char *	pend,
		CONV_RESULT *	cr
	)			[static]

convert a number in string to a TDSNUMERIC

Returns:

sizeof(TDS_NUMERIC) on success, TDS_CONVERT_* failure code on failure

static int stringz_to_numeric	(	const char *	instr,
		CONV_RESULT *	cr
	)			[static]

convert a zero terminated string to NUMERIC

Returns:

sizeof(TDS_NUMERIC) on success, TDS_CONVERT_* failure code on failure

TDS_INT tds_convert	(	const TDSCONTEXT *	tds_ctx,
		int	srctype,
		const TDS_CHAR *	src,
		TDS_UINT	srclen,
		int	desttype,
		CONV_RESULT *	cr
	)

tds_convert convert a type to another.

If you convert to SYBDECIMAL/SYBNUMERIC you MUST initialize precision and scale of cr. Do not expect strings to be zero terminated. Databases support zero inside string. Using strlen may result on data loss or even a segmentation fault. Instead, use memcpy to copy destination using length returned. This function does not handle NULL, srclen should be >0. Client libraries handle NULLs each in their own way.

Parameters:

	tds_ctx	context (used in conversion to data and to return messages)
	srctype	type of source
	src	pointer to source data to convert
	srclen	length in bytes of source (not counting terminator or strings)
	desttype	type of destination
	cr	structure to hold result

Returns:

length of result or TDS_CONVERT_* failure code on failure. All TDS_CONVERT_* constants are <0.

TDS_INT tds_datecrack	(	TDS_INT	datetype,
		const void *	di,
		TDSDATEREC *	dr
	)

Convert from db date format to a structured date format.

Parameters:

	datetype	source date type. SYBDATETIME or SYBDATETIME4
	di	source date
	dr	destination date

Returns:

TDS_FAIL or TDS_SUCCEED

TDS_INT tds_get_null_type

(

int

srctype

)

Get same type but nullable.

Parameters:

srctype

type requires

Returns:

nullable type

size_t tds_strftime	(	char *	buf,
		size_t	maxsize,
		const char *	format,
		const TDSDATEREC *	dr
	)

format a date string according to an "extended" strftime(3) formatting definition.

Parameters:

	buf	output buffer
	maxsize	size of buffer in bytes (space include terminator)
	format	format string passed to strftime(3), except that z represents milliseconds
	dr	date to convert

Returns:

length of string returned, 0 for error

unsigned char tds_willconvert	(	int	srctype,
		int	desttype
	)

Test if a conversion is possible.

Parameters:

	srctype	source type
	desttype	destination type

Returns:

0 if not convertible