generic.h File Reference

Generic. More...

#include <stddef.h>
#include <assert.h>

Go to the source code of this file.

Heap allocation
#define	VL_PRINTF(format,...)   ((*vl_printf_func)((format), __VA_ARGS__))
	Call user-customizable printf function.
#define	VL_PRINT(string)   ((*vl_printf_func)(string))
	Call user-customizable printf function (no varags).
void	vl_set_alloc_func (void *(*malloc_func)(vl_size), void *(*realloc_func)(void *, vl_size), void *(*calloc_func)(vl_size, vl_size), void(*free_func)(void *))
	Set memory allocation functions.
VL_INLINE void *	vl_malloc (vl_size n)
	Call customizable malloc function.
VL_INLINE void *	vl_realloc (void *ptr, vl_size n)
	Call customizable resize function.
VL_INLINE void *	vl_calloc (vl_size n, vl_size size)
	Call customizable calloc function.
VL_INLINE void	vl_free (void *ptr)
	Call customizable free function.
void	vl_set_printf_func (int(*printf_func)(char const *str,...))
	Call user-customizable printf function.
Error handling
#define	VL_ERR_MSG_LEN   1024
	Error description maximum length.
#define	VL_ERR_OK   0
#define	VL_ERR_OVERFLOW   1
#define	VL_ERR_ALLOC   2
#define	VL_ERR_BAD_ARG   3
#define	VL_ERR_IO   4
#define	VL_ERR_EOF   5
#define	VL_ERR_NO_MORE   5
int	vl_err_no
	Last error code.
char	vl_err_msg [VL_ERR_MSG_LEN]
	Last error description.
Endianness detection and conversions
#define	VL_LITTLE_ENDIAN   0
#define	VL_BIG_ENDIAN   1
#define	VL_ENDIANNESS   VL_BIG_ENDIAN
	Host endianness.
VL_INLINE int	vl_get_endianness ()
	Get endianness.
VL_INLINE void	vl_adapt_endianness_8 (void *dst, void *src)
	Change endianness of 8-byte value if required.
VL_INLINE void	vl_adapt_endianness_4 (void *dst, void *src)
	Change endianness of 4-byte value if required.
VL_INLINE void	vl_adapt_endianness_2 (void *dst, void *src)
	Change endianness of 2-byte value if required.
Defines
#define	VL_VERSION_STRING   "0.1"
	Library version string.
#define	VL_INLINE   static __inline__
	Inline function declaration.
#define	VL_STRINGIFY_(x)   # x
	Stringify argument helper.
#define	VL_STRINGIFY(x)   VL_STRINGIFY_(x)
	Stringify macro.
#define	VL_BIG_INT   2147483647
	Big integer.
#define	VL_SMALL_INT   (- VL_BIG_INT - 1)
	Small integer.
#define	VL_LOG_OF_2   0.693147180559945
	Logarithm of 2.
#define	VL_NAN_F   (vl_nan_f.value)
	Single NaN (not signaling).
#define	VL_INFINITY_F   (vl_infinity_f.value)
	Single Infinity (not signaling).
#define	VL_NAN_D   (vl_nan_d.value)
	Double NaN (not signaling).
#define	VL_INFINITY_D   (vl_infinity_d.value)
	Double Infinity (not signaling).
Common operations
#define	VL_MIN(x, y)   (((x)<(y))?(x):(y))
	Min operation.
#define	VL_MAX(x, y)   (((x)>(y))?(x):(y))
	Max operation.
#define	VL_SHIFT_LEFT(x, n)   (((n)>=0)?((x)<<(n)):((x)>>-(n)))
	Signed left shift operation.
Typedefs
Atomic data types
typedef long long	vl_int64
typedef int	vl_int32
typedef short	vl_int16
typedef char	vl_int8
typedef long long unsigned	vl_uint64
typedef int unsigned	vl_uint32
typedef short unsigned	vl_uint16
typedef char unsigned	vl_uint8
typedef int	vl_int
typedef unsigned int	vl_uint
typedef float	vl_single
typedef double	vl_double
typedef unsigned int	vl_uidx
typedef size_t	vl_size
typedef int	vl_bool
Functions
char const *	vl_get_version_string ()
	Get version string.
Variables
int(*	vl_printf_func )(char const *format,...)
	Customizable printf function pointer.
void *(*	vl_malloc_func )(vl_size)
	Customizable malloc function pointer.
void *(*	vl_realloc_func )(void *, vl_size)
	Customizable realloc function pointer.
void *(*	vl_calloc_func )(vl_size, vl_size)
	Customizable calloc function pointer.
void(*	vl_free_func )(void *)
	Customizable free function pointer.

---

Detailed Description

Author:

Andrea Vedaldi

This module provides basic facilities such as atomi types definitions, error handling, endianness detection, serialization, logging.

Error handling

Error handling uses the same style of the standard C library. Most functions return 0 when they succeed and -1 when they fail, and set the global variable vl_err_no with a code identifying the error occurred. This variable is never set on success and should be examinated right after an error occurred.

Endinanness detection and conversions

An architecture is big endiand or little endian depending how multi-btye data are stored in memory:

• big endian (big end first - Network order) if it stores the most significant byte has the smaller memory address.
• little endian (small end first - Intel format) if it stores the lesser significant byte at the smaller memory address.

Use the function vl_get_endianness() to detect endianness. To serialize/deserialize data in big endian (network) order, call the functions vl_adapt_endianness_8(), vl_adapt_endianness_4(), vl_adapt_endianness_2() after reading and before writing (the functions change edinanness only if the architecture is little endian and do nothing otherwise).

Author:

Andrea Vedaldi

---

Define Documentation

#define VL_BIG_ENDIAN   1

big endian.

#define VL_ENDIANNESS   VL_BIG_ENDIAN

This macro is equal to VL_BIG_ENDIAN or VL_LITTLE_ENDIAN depending on the endianness of the host.

#define VL_ERR_ALLOC   2

Resource allocation error

#define VL_ERR_BAD_ARG   3

Bad argument or illegal data error

#define VL_ERR_EOF   5

End-of-file or end-of-sequence error

#define VL_ERR_IO   4

Input/output error

#define VL_ERR_MSG_LEN   1024

This is the size of the vl_err_msg buffer.

#define VL_ERR_NO_MORE   5

End-of-sequence

Deprecated:

#define VL_ERR_OK   0

No error

#define VL_ERR_OVERFLOW   1

Buffer overflow error

#define VL_LITTLE_ENDIAN   0

little endian.

#define VL_MAX	(	x,
		y		)	(((x)>(y))?(x):(y))

Parameters:

	x	value.
	y	value.

Returns:

the maximum of x and y.

#define VL_MIN	(	x,
		y		)	(((x)<(y))?(x):(y))

Parameters:

	x	value
	y	value

Returns:

the minimum of x and y.

#define VL_PRINT

(

string

)

((*vl_printf_func)(string))

Parameters:

string

string to print.

This macro is the same as VL_PRINTF() and should be used when the variable list of arguments is empty.

Returns:

results of the user-customizable printf.

#define VL_PRINTF	(	format,
		...		)	((*vl_printf_func)((format), __VA_ARGS__))

Parameters:

	format	format string.
	...	printf variable arguments.

The function calls the user customizable printf.

Returns:

results of the user-customizable printf.

#define VL_SHIFT_LEFT	(	x,
		n		)	(((n)>=0)?((x)<<(n)):((x)>>-(n)))

The macro is equivalent to the builtin << operator, but it supports negative shifts too.

Parameters:

	x	value.
	n	number of shift positions.

Returns:

x << n .

#define VL_STRINGIFY

(

x

)

VL_STRINGIFY_(x)

Parameters:

x

macro to stringify

For instance, the following fragment

 #define A x.y.z
 printf(VL_STRINGIFY(A)) ;

will print the string x.y.z.

#define VL_STRINGIFY_

(

x

)

# x

For internal use only.

See also:

VL_STRINGIFY

---

Typedef Documentation

typedef int vl_bool

boolean

typedef double vl_double

double precision float.

typedef int vl_int

integer.

typedef short vl_int16

signed 16-bit integer.

typedef int vl_int32

signed 32-bit integer.

typedef long long vl_int64

signed 64-bit integer.

typedef char vl_int8

signed 8-bit integer.

typedef float vl_single

single precision float.

typedef size_t vl_size

size data type.

typedef unsigned int vl_uidx

unsigned index data type.

typedef unsigned int vl_uint

unsigned integer.

typedef short unsigned vl_uint16

unsigned 16-bit integer.

typedef int unsigned vl_uint32

unsigned 32-bit integer.

typedef long long unsigned vl_uint64

unsigned 64-bit integer.

typedef char unsigned vl_uint8

unsigned 8-bit integer.

---

Function Documentation

VL_INLINE void vl_adapt_endianness_2	(	void *	dst,
		void *	src
	)

Parameters:

	dst	destination 2-byte buffer.
	src	source 2-byte bufffer.

See also:

generic-endianness.

VL_INLINE void vl_adapt_endianness_4	(	void *	dst,
		void *	src
	)

Parameters:

	dst	destination 4-byte buffer.
	src	source 4-byte bufffer.

See also:

Endinanness detection and conversions

VL_INLINE void vl_adapt_endianness_8	(	void *	dst,
		void *	src
	)

Parameters:

	dst	destination 8-byte buffer.
	src	source 8-byte bufffer.

See also:

Endinanness detection and conversions.

VL_INLINE void * vl_calloc	(	vl_size	n,
		vl_size	size
	)

Parameters:

	n	size of each element in byte.
	size	size of the array to allocate (number of elements).

The function calls the user-customizable calloc.

Returns:

result of the user-customizable calloc.

VL_INLINE void vl_free

(

void *

ptr

)

Parameters:

ptr

buffer to free.

The function calls the user customizable free.

VL_INLINE int vl_get_endianness

(

)

Returns:

VL_BIG_ENDIAN or VL_LITTLE_ENDIAN depending on the host endianness.

See also:

Endinanness detection and conversions

char const* vl_get_version_string

(

)

Returns:

library version string

VL_INLINE void * vl_malloc

(

vl_size

n

)

Parameters:

n

number of bytes to allocate.

The function calls the user customizable malloc.

Returns:

result of malloc

VL_INLINE void * vl_realloc	(	void *	ptr,
		vl_size	n
	)

Parameters:

	ptr	buffer to reallocate.
	n	number of bytes to allocate.

The function calls the user-customizable realloc.

Returns:

result of the user-customizable realloc.

void vl_set_alloc_func	(	void *(*)(vl_size)	malloc_func,
		void *(*)(void *, vl_size)	realloc_func,
		void *(*)(vl_size, vl_size)	calloc_func,
		void(*)(void *)	free_func
	)

Parameters:

	malloc_func	pointer to malloc.
	realloc_func	pointer to realloc.
	calloc_func	pointer to calloc.
	free_func	pointer to free.

void vl_set_printf_func

(

int(*)(char const *str,...)

printf_func

)

Parameters:

	format	format string.
	...	printf variable arguments.

The function calls the user customizable printf.

Returns:

results of the user-customizable printf.

---

Variable Documentation

void*(* vl_calloc_func)(vl_size, vl_size)

For internal use only.

void(* vl_free_func)(void *)

For internal use only.

void*(* vl_malloc_func)(vl_size)

For internal use only.

int(* vl_printf_func)(char const *format,...)

For internal use only.

void*(* vl_realloc_func)(void *, vl_size)

For internal use only.

---