kdbhelper.h File Reference

Helper for memory management. More...

#include <kdbmacros.h>
#include <kdbtypes.h>
#include <stdarg.h>
#include <stddef.h>

Include dependency graph for kdbhelper.h:

This graph shows which files directly or indirectly include this file:

Enumerations
enum	elektraLookupOptions {   KDB_O_SPEC = 1 << 15 , KDB_O_CREATE = 1 << 16 , KDB_O_NOCASCADING = 1 << 17 , KDB_O_NOSPEC = 1 << 18 ,   KDB_O_NODEFAULT = 1 << 19 , KDB_O_CALLBACK = 1 << 20 , KDB_O_OPMPHM = 1 << 21 , KDB_O_BINSEARCH = 1 << 22 }
	More lookup options. More...

Functions
void *	elektraMalloc (size_t size)
	Allocate memory for Elektra. More...
void *	elektraCalloc (size_t size)
	Allocate memory for Elektra. More...
void	elektraFree (void *ptr)
	Free memory of Elektra or its backends. More...
int	elektraRealloc (void **buffer, size_t size)
	Reallocate Storage in a save way. More...
char *	elektraStrDup (const char *s)
	Copy string into new allocated memory. More...
void *	elektraMemDup (const void *s, size_t l)
	Copy buffer into new allocated memory. More...
char char *	elektraVFormat (const char *format, va_list arg_list)
	Does string formatting in fresh allocated memory. More...
int	elektraStrCmp (const char *s1, const char *s2)
	Compare Strings. More...
int	elektraStrNCmp (const char *s1, const char *s2, size_t n)
	Compare Strings up to a maximum length. More...
int	elektraStrCaseCmp (const char *s1, const char *s2)
	Compare Strings ignoring case. More...
int	elektraStrNCaseCmp (const char *s1, const char *s2, size_t n)
	Compare Strings ignoring case up to a maximum length. More...
int	elektraMemCaseCmp (const char *s1, const char *s2, size_t size)
	Compare two memory regions but make cmp chars uppercase before comparison. More...
size_t	elektraStrLen (const char *s)
	Calculates the length in bytes of a string. More...

Detailed Description

Helper for memory management.

Should be always preferred. Can be used for profiling and tracing.

Copyright

BSD License (see LICENSE.md or https://www.libelektra.org)

Enumeration Type Documentation

elektraLookupOptions

enum elektraLookupOptions

More lookup options.

Enumerator
KDB_O_SPEC	Use the passed key as specification, instead of looking up the specification first.
KDB_O_CREATE	Create the key if it was not found.
KDB_O_NOCASCADING	Disable cascading search for keys starting with /.
KDB_O_NOSPEC	Do not use specification for cascading keys (internal)
KDB_O_NODEFAULT	Do not honor the default spec (internal)
KDB_O_CALLBACK	For spec:/ lookups that traverse deeper into hierarchy (callback in ksLookup())
KDB_O_OPMPHM	Overrule ksLookup search predictor to use OPMPHM, make sure to set ENABLE_OPTIMIZATIONS=ON at cmake.
KDB_O_BINSEARCH	Overrule ksLookup search predictor to use Binary search for lookup.

Function Documentation

elektraCalloc()

void* elektraCalloc

(

size_t

size

)

Allocate memory for Elektra.

Memory will be set to 0.

Parameters

size	the requested size

See also

elektraMalloc

elektraFree()

void elektraFree

(

void *

ptr

)

Free memory of Elektra or its backends.

Parameters

ptr	the pointer to free

If ptr is NULL, no operation is performed.

See also

elektraMalloc

elektraMalloc()

void* elektraMalloc

(

size_t

size

)

Allocate memory for Elektra.

if ((buffer = elektraMalloc (length)) == 0) {
        // here comes the failure handler
        // no allocation happened here, so don't use buffer
#if DEBUG
        fprintf (stderr, "Allocation error");
#endif
        // return with error
}

Parameters

size	the requested size

This function is compatible to ANSI-C malloc

See also

elektraFree

elektraCalloc

elektraMemCaseCmp()

int elektraMemCaseCmp	(	const char *	s1,
		const char *	s2,
		size_t	size
	)

Compare two memory regions but make cmp chars uppercase before comparison.

Parameters

s1	The first string to be compared
s2	The second string to be compared
size	to be compared

Returns

a negative number if s1 is less than s2

Return values

0	if s1 matches s2

Returns

a positive number if s1 is greater than s2

elektraMemDup()

void* elektraMemDup	(	const void *	s,
		size_t	n
	)

Copy buffer into new allocated memory.

You need to free the memory yourself.

This function also works with \0 characters in the buffer. The length is taken as given, it must be correct.

Returns

0 if out of memory, a pointer otherwise

Parameters

s	must be an allocated buffer
n	the number of bytes to copy from s

elektraRealloc()

int elektraRealloc	(	void **	buffer,
		size_t	size
	)

Reallocate Storage in a save way.

if (elektraRealloc ((void **) & buffer, new_length) < 0) {
        // here comes the failure handler
        // you can still use the old buffer
#if DEBUG
        fprintf (stderr, "Reallocation error\n");
#endif
        elektraFree (buffer);
        buffer = 0;
        // return with error
}

Parameters

buffer	is a pointer to a elektraMalloc
size	is the new size for the memory

Return values

-1	on failure
0	on success

elektraStrCaseCmp()

int elektraStrCaseCmp	(	const char *	s1,
		const char *	s2
	)

Compare Strings ignoring case.

Parameters

s1	The first string to be compared
s2	The second string to be compared

Returns

a negative number if s1 is less than s2

Return values

0	if s1 matches s2

Returns

a positive number if s1 is greater than s2

elektraStrCmp()

int elektraStrCmp	(	const char *	s1,
		const char *	s2
	)

Compare Strings.

Parameters

s1	The first string to be compared
s2	The second string to be compared

Returns

a negative number if s1 is less than s2

Return values

0	if s1 matches s2

Returns

a positive number if s1 is greater than s2

elektraStrDup()

char* elektraStrDup

(

const char *

s

)

Copy string into new allocated memory.

You need to free the memory yourself.

Note

that size is determined at runtime. So if you have a size information, don't use that function.

Parameters

s	the null-terminated string to duplicate

Returns

0 if out of memory, a pointer otherwise

Precondition

s must be a c-string.

See also

elektraFree

elektraStrLen

elektraMemDup

elektraStrLen()

size_t elektraStrLen

(

const char *

s

)

Calculates the length in bytes of a string.

This function differs from strlen() because it is Unicode and multibyte chars safe. While strlen() counts characters and ignores the final NULL, elektraStrLen() count bytes including the ending NULL.

It must not be used to search for / in the name, because it does not consider escaping. Instead use the unescaped name.

See also

keyUnescapedName()

Parameters

s	the string to get the length from

Returns

number of bytes used by the string, including the final NULL.

elektraStrNCaseCmp()

int elektraStrNCaseCmp	(	const char *	s1,
		const char *	s2,
		size_t	n
	)

Compare Strings ignoring case up to a maximum length.

Parameters

s1	The first string to be compared
s2	The second string to be compared
n	The maximum length to be compared

Returns

a negative number if s1 is less than s2

Return values

0	if s1 matches s2

Returns

a positive number if s1 is greater than s2

elektraStrNCmp()

int elektraStrNCmp	(	const char *	s1,
		const char *	s2,
		size_t	n
	)

Compare Strings up to a maximum length.

Parameters

s1	The first string to be compared
s2	The second string to be compared
n	The maximum length to be compared

Returns

a negative number if s1 is less than s2

Return values

0	if s1 matches s2

Returns

a positive number if s1 is greater than s2

elektraVFormat()

char char* elektraVFormat	(	const char *	format,
		va_list	arg_list
	)

Does string formatting in fresh allocated memory.

Parameters

format	as in vprintf()
arg_list	as in vprintf()

Returns

new allocated memory (free with elektraFree)