generic.c File Reference

Generic - Definition. More...

#include "generic.h"
#include <assert.h>
#include <stdlib.h>
#include <stdio.h>
#include <stdarg.h>
#include <math.h>
#include <Windows.h>
#include <unistd.h>

Functions
VlState *	vl_get_state (void)
	Return VLFeat global state.
VlThreadState *	vl_get_thread_specific_state (void)
	Get VLFeat thread state.
static void	vl_lock_state (void)
	Lock VLFeat state.
static void	vl_unlock_state (void)
	Unlock VLFeat state.
static VlThreadState *	vl_thread_specific_state_new (void)
	Construct a new thread state object.
static void	vl_thread_specific_state_delete (VlThreadState *self)
	Delete a thread state structure.
char const *	vl_get_version_string ()
	Get VLFeat version string.
char *	vl_configuration_to_string_copy ()
	Get VLFeat configuration string.
static int	do_nothing_printf (char const *format,...)
	A printf that does not do anything.
vl_size	vl_get_num_cpus (void)
	Get the number of CPU cores of the host.
void	vl_set_simd_enabled (vl_bool x)
	Toggle usage of SIMD instructions.
vl_bool	vl_get_simd_enabled (void)
	Are SIMD instructons enabled?
vl_bool	vl_cpu_has_avx (void)
	Check for AVX instruction set.
vl_bool	vl_cpu_has_sse3 (void)
	Check for SSE3 instruction set.
vl_bool	vl_cpu_has_sse2 (void)
	Check for SSE2 instruction set.
vl_size	vl_get_max_threads (void)
	Get the maximum number of computational threads.
void	vl_set_num_threads (vl_size numThreads)
	Set the number of threads targeted for parallel computations.
int	vl_set_last_error (int error, char const *errorMessage,...)
	Set last VLFeat error.
int	vl_get_last_error (void)
	Get the code of the last error.
char const *	vl_get_last_error_message (void)
	Get the last error message.
void	vl_set_alloc_func (void *(*malloc_func)(size_t), void *(*realloc_func)(void *, size_t), void *(*calloc_func)(size_t, size_t), void(*free_func)(void *))
	Set memory allocation functions.
void *	vl_malloc (size_t n)
	Allocate a memory block.
void *	vl_realloc (void *ptr, size_t n)
	Reallocate a memory block.
void *	vl_calloc (size_t n, size_t size)
	Free and clear a memory block.
void	vl_free (void *ptr)
	Free a memory block.
void	vl_set_printf_func (printf_func_t printf_func)
	Set the printf function.
printf_func_t	vl_get_printf_func (void)
	Get the printf function.
double	vl_get_cpu_time ()
	Get processor time.
void	vl_tic (void)
	Reset processor time reference The function resets VLFeat TIC/TOC time reference. There is one such reference per thread.
double	vl_toc (void)
	Get elapsed time since tic.
VlRand *	vl_get_rand (void)
	Get the default random number generator.
static void	vl_constructor (void)
	Initialize VLFeat state.
static void	vl_destructor ()
	Destruct VLFeat.

---

Detailed Description

Author:

Andrea Vedaldi

---

Function Documentation

static int do_nothing_printf ( char const *  format,   ...  )

static

void* vl_calloc	(	size_t	n,
		size_t	size
	)

Parameters:

n	number of items to allocate.
size	size in bytes of an item.

Returns:

pointer to the new block.

This function allocates and clears a memory block. The synopsis is the same as the POSIX calloc function.

char* vl_configuration_to_string_copy

(

void

)

Returns:

a new configuration string.

The function returns a new string containing a human readable description of the library configuration.

static void vl_constructor ( void  )

static

vl_bool vl_cpu_has_avx

(

void

)

Returns:

true if AVX is present.

vl_bool vl_cpu_has_sse2

(

void

)

Returns:

true if SSE2 is present.

vl_bool vl_cpu_has_sse3

(

void

)

Returns:

true if SSE3 is present.

static void vl_destructor ( )

static

void vl_free

(

void *

ptr

)

Parameters:

ptr	pointer to the memory block.

This function frees a memory block allocated by vl_malloc, vl_calloc, or vl_realloc. The synopsis is the same as the POSIX malloc function.

double vl_get_cpu_time

(

void

)

Returns:

processor time in seconds.

See also:

vl_tic, vl_toc

int vl_get_last_error

(

void

)

Returns:

error code.

See also:

vl_get_last_error_message.

char const* vl_get_last_error_message

(

void

)

Returns:

pointer to the error message.

See also:

vl_get_last_error.

vl_size vl_get_max_threads

(

void

)

Returns:

number of threads.

See also:

vl_set_num_threads(), Parallel computations

vl_size vl_get_num_cpus

(

void

)

Returns:

number of CPU cores.

printf_func_t vl_get_printf_func

(

void

)

Returns:

printf_func pointer to the printf implementation.

See also:

vl_set_printf_func.

VlRand* vl_get_rand

(

void

)

Returns:

random number generator.

The function returns a pointer to the default random number genrator. There is one such generator per thread.

vl_bool vl_get_simd_enabled

(

void

)

Returns:

true if SIMD instructions are enabled.

VlState * vl_get_state ( void  )

inline

The function returns a pointer to VLFeat global state.

Returns:

pointer to the global state structure.

VlThreadState * vl_get_thread_specific_state ( void  )

inline

Returns:

pointer to the thread state structure.

The function returns a pointer to VLFeat thread state.

char const* vl_get_version_string

(

void

)

Returns:

the library version string.

static void vl_lock_state ( void  )

static

The function locks VLFeat global state mutex.

The mutex is recursive: locking multiple times from the same thread is a valid operations, but requires an equivalent number of calls to vl_unlock_state.

See also:

vl_unlock_state

void* vl_malloc

(

size_t

n

)

Parameters:

n	size in bytes of the new block.

Returns:

pointer to the allocated block.

This function allocates a memory block of the specified size. The synopsis is the same as the POSIX malloc function.

void* vl_realloc	(	void *	ptr,
		size_t	n
	)

Parameters:

ptr	pointer to a memory block previously allocated.
n	size in bytes of the new block.

Returns:

pointer to the new block.

This function reallocates a memory block to change its size. The synopsis is the same as the POSIX realloc function.

void vl_set_alloc_func	(	void *(*)(size_t)	malloc_func,
		void *(*)(void *, size_t)	realloc_func,
		void *(*)(size_t, size_t)	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.

int vl_set_last_error	(	int	error,
		char const *	errorMessage,
			...
	)

Parameters:

error	error code.
errorMessage	error message format string.
...	format string arguments.

Returns:

error code.

The function sets the code and optionally the error message of the last encountered error. errorMessage is the message format. It uses the printf convention and is followed by the format arguments. The maximum lenght of the error message is given by VL_ERR_MSG_LEN (longer messages are truncated).

Passing NULL as errorMessage sets the error message to the empty string.

void vl_set_num_threads

(

vl_size

numThreads

)

Parameters:

numThreads

number of threads to use.

See also:

vl_get_max_threads(), Parallel computations

void vl_set_printf_func

(

printf_func_t

printf_func

)

Parameters:

printf_func

pointer to a printf implementation. Set print_func to NULL to disable printf.

vl_set_simd_enabled

(

vl_bool

x

)

Parameters:

x	true if SIMD instructions are used.

Notice that SIMD instructions are used only if the CPU model supports them. Note alsoc that data alignment may restrict the use of such instructions.

See also:

vl_cpu_has_sse2(), vl_cpu_has_sse3(), etc.

static void vl_thread_specific_state_delete ( VlThreadState *  self )

static

Parameters:

self	thread state object.

static VlThreadState * vl_thread_specific_state_new ( void  )

static

Returns:

new state structure.

void vl_tic

(

void

)

See also:

vl_get_cpu_time, vl_toc.

double vl_toc

(

void

)

Returns:

elapsed time in seconds.

The function returns the processor time elapsed since vl_tic was called last.

Remarks:

In multi-threaded applications, there is an independent timer for each execution thread.

On UNIX, this function uses the clock() system call. On Windows, it uses the QueryPerformanceCounter() system call, which is more accurate than clock() on this platform.

static void vl_unlock_state ( void  )

static

The function unlocks VLFeat global state mutex.

See also:

vl_lock_state