Memory Slices

These functions provide memory slices in read-only and read-write forms. More...

Data Structures
struct	_Eina_Slice
	Defines a read-only memory region. More...
struct	_Eina_Rw_Slice
	Defines a read-and-write able memory region. More...

Macros
#define	EINA_SLICE_ARRAY(buf)   {.len = ((sizeof(buf) / sizeof((buf)[0])) * sizeof((buf)[0])), .mem = (buf)}
	Initializer for arrays of any kind. More...
#define	EINA_RW_SLICE_DECLARE(name, length)
	Declare a local (stack) array for storage at given length and initialize an Eina_Rw_Slice called name. More...
#define	EINA_SLICE_STR_LITERAL(buf)   {.len = (sizeof("" buf) - 1), .mem = (buf)}
	Initializer for string literals (those declared as double-quoted). More...
#define	EINA_SLICE_STR(str)   {.len = strlen((str)), .mem = (str)}
	Initializer for strings (uses strlen()). More...
#define	EINA_SLICE_STR_FULL(str)   {.len = strlen((str)) + 1, .mem = (str)}
	Same as EINA_SLICE_STR_FULL, but it also contains the \0 element of the string. More...
#define	EINA_SLICE_STR_FMT   "%.*s"
	To be used in printf()-like statements, prints the slice as a string, its len is to be used, then it doesn't need the null terminator. More...
#define	EINA_SLICE_STR_PRINT(s)   (int)(s).len, (const char *)(s).mem
	To be used in printf()-like statements when EINA_SLICE_STR_FMT was used, it will print the slice as a string up to len. More...
#define	EINA_SLICE_FMT   "%p+%zu"
	To be used in printf()-like statements, prints the slice as 0x1234+12 (mem + len). More...
#define	EINA_SLICE_PRINT(s)   (s).mem, (s).len
	To be used in printf()-like statements when EINA_SLICE_FMT was used, it will print the slice mem and len. More...
#define	EINA_SLICE_FOREACH(s, itr)
	Iterate over the slice memory, using itr. More...

Typedefs
typedef struct _Eina_Slice	Eina_Slice
	Defines a read-only memory region. More...
typedef struct _Eina_Rw_Slice	Eina_Rw_Slice
	Defines a read-and-write able memory region. More...

Functions
static Eina_Slice	eina_rw_slice_slice_get (const Eina_Rw_Slice rw_slice)
	Convert the Read-write slice to read-only. More...
static Eina_Rw_Slice	eina_slice_dup (const Eina_Slice slice)
	Creates a duplicate of slice's memory. More...
static Eina_Rw_Slice	eina_rw_slice_dup (const Eina_Rw_Slice rw_slice)
	Creates a duplicate of slice's memory. More...
static int	eina_slice_compare (const Eina_Slice a, const Eina_Slice b)
	Compare two slices, similar to memcmp() More...
static int	eina_rw_slice_compare (const Eina_Rw_Slice a, const Eina_Rw_Slice b)
	Compare two slices, similar to memcmp() More...
static Eina_Rw_Slice	eina_rw_slice_copy (const Eina_Rw_Slice dest, const Eina_Slice src)
	Copy a read-only slice to a read-write one, similar to memcpy(). More...
static Eina_Slice	eina_slice_seek (const Eina_Slice slice, ssize_t offset, int whence)
	Seek within a slice, similar to fseek(). More...
static Eina_Rw_Slice	eina_rw_slice_seek (const Eina_Rw_Slice rw_slice, ssize_t offset, int whence)
	Seek within a read-write slice, similar to fseek(). More...
static const void *	eina_slice_strchr (const Eina_Slice slice, int c)
	Find a character inside the slice, similar to memchr(). More...
static const void *	eina_slice_find (const Eina_Slice slice, const Eina_Slice needle)
	Find a needle inside the slice, similar to memmem(). More...
static Eina_Bool	eina_slice_startswith (const Eina_Slice slice, const Eina_Slice prefix)
	Checks if the slice starts with a prefix. More...
static Eina_Bool	eina_slice_endswith (const Eina_Slice slice, const Eina_Slice suffix)
	Checks if the slice ends with a suffix. More...
static void *	eina_rw_slice_strchr (const Eina_Rw_Slice rw_slice, int c)
	Find a character inside the slice, similar to memchr(). More...
static void *	eina_rw_slice_find (const Eina_Rw_Slice rw_slice, const Eina_Slice needle)
	Find a needle inside the slice, similar to memmem(). More...
static Eina_Bool	eina_rw_slice_startswith (const Eina_Rw_Slice slice, const Eina_Slice prefix)
	Checks if the slice starts with a prefix. More...
static Eina_Bool	eina_rw_slice_endswith (const Eina_Rw_Slice slice, const Eina_Slice suffix)
	Checks if the slice ends with a suffix. More...
static const void *	eina_slice_end_get (const Eina_Slice slice)
	The memory position where the slice ends. More...
static void *	eina_rw_slice_end_get (const Eina_Rw_Slice rw_slice)
	The memory position where the slice ends. More...
static char *	eina_slice_strdup (const Eina_Slice slice)
	A null-terminated string for this slice. More...
static char *	eina_rw_slice_strdup (const Eina_Rw_Slice rw_slice)
	A null-terminated string for this slice. More...

Detailed Description

These functions provide memory slices in read-only and read-write forms.

Memory slices define a contiguous linear memory starting at a given pointer (mem) and spanning for a given length (len).

They may be read-only (Eina_Slice) or read-write (Eina_Rw_Slice).

Since

1.19

Macro Definition Documentation

EINA_SLICE_ARRAY

#define EINA_SLICE_ARRAY

(

buf

)

{.len = ((sizeof(buf) / sizeof((buf)[0])) * sizeof((buf)[0])), .mem = (buf)}

Initializer for arrays of any kind.

Parameters

[in]

buf

The array to create the slice from.

Returns

The initialized slice object.

It is often useful for globals.

Note

This macro is usable with both Eina_Slice or Eina_Rw_Slice.

static uint8_t buf[1024];
static Eina_Slice rw_slice = EINA_SLICE_ARRAY(buf);

See also

EINA_SLICE_STR_LITERAL() for specific version that checks for string literals.

Since

1.19

EINA_RW_SLICE_DECLARE

#define EINA_RW_SLICE_DECLARE	(		name,
			length
	)

Value:

  uint8_t _eina_slice_storage_ ## name [(length)] = { 0 }; \
  Eina_Rw_Slice name = EINA_SLICE_ARRAY(_eina_slice_storage_ ## name)

Declare a local (stack) array for storage at given length and initialize an Eina_Rw_Slice called name.

Parameters

[in]	name	the name of the variable to be the Eina_Rw_Slice.
[in]	length	the size in bytes of the storage.

Since

1.19

EINA_SLICE_STR_LITERAL

#define EINA_SLICE_STR_LITERAL

(

buf

)

{.len = (sizeof("" buf) - 1), .mem = (buf)}

Initializer for string literals (those declared as double-quoted).

The size will NOT include the trailing null-terminator.

It is often useful for globals.

Parameters

[in]

buf

The array to create the slice from.

Returns

The initialized slice object.

Note

This macro is usable with both Eina_Slice or Eina_Rw_Slice.

static const Eina_Slice ro_slice = EINA_SLICE_STR_LITERAL("hello world");

See also

EINA_SLICE_STR() for more generic version.

EINA_SLICE_ARRAY() for version that uses a general array.

Since

1.19

EINA_SLICE_STR

#define EINA_SLICE_STR

(

str

)

{.len = strlen((str)), .mem = (str)}

Initializer for strings (uses strlen()).

Parameters

[in]

str

The string to create the slice from.

Returns

The initialized slice object.

Note

This macro is usable with both Eina_Slice or Eina_Rw_Slice.

Eina_Slice ro_slice = EINA_SLICE_STR("hello world");

See also

EINA_SLICE_STR() for specific version using literals.

Since

1.19

EINA_SLICE_STR_FULL

#define EINA_SLICE_STR_FULL

(

str

)

{.len = strlen((str)) + 1, .mem = (str)}

Same as EINA_SLICE_STR_FULL, but it also contains the \0 element of the string.

Parameters

[in]

str

The string to create the slice from.

Returns

The initialized slice object.

Note

This macro is usable with both Eina_Slice or Eina_Rw_Slice.

Eina_Slice ro_slice = EINA_SLICE_STR_FULL("hello world");

See also

EINA_SLICE_STR_FULL() for specific version using literals.

Since

1.24

EINA_SLICE_STR_FMT

#define EINA_SLICE_STR_FMT   "%.*s"

To be used in printf()-like statements, prints the slice as a string, its len is to be used, then it doesn't need the null terminator.

Use with EINA_SLICE_STR_PRINT()

Note

This macro is usable with both Eina_Slice or Eina_Rw_Slice.

Eina_Slice s = EINA_SLICE_STR_LITERAL("hello");
printf("s=" EINA_SLICE_STR_FMT "\n", EINA_SLICE_STR_PRINT(s));

Since

1.19

EINA_SLICE_STR_PRINT

#define EINA_SLICE_STR_PRINT

(

s

)

(int)(s).len, (const char *)(s).mem

To be used in printf()-like statements when EINA_SLICE_STR_FMT was used, it will print the slice as a string up to len.

Parameters

[in]

s

The slice.

Returns

The arguments for an EINA_SLICE_STR_FMT formatted printf.

Use with EINA_SLICE_STR_FMT.

Note

This macro is usable with both Eina_Slice or Eina_Rw_Slice.

Eina_Slice s = EINA_SLICE_STR_LITERAL("hello");
printf("s=" EINA_SLICE_STR_FMT "\n", EINA_SLICE_STR_PRINT(s));

Since

1.19

EINA_SLICE_FMT

#define EINA_SLICE_FMT   "%p+%zu"

To be used in printf()-like statements, prints the slice as 0x1234+12 (mem + len).

Use with EINA_SLICE_PRINT()

Note

This macro is usable with both Eina_Slice or Eina_Rw_Slice.

Eina_Slice s = EINA_SLICE_STR_LITERAL("hello");
printf("s=" EINA_SLICE_FMT "\n", EINA_SLICE_PRINT(s));

Since

1.19

EINA_SLICE_PRINT

#define EINA_SLICE_PRINT

(

s

)

(s).mem, (s).len

To be used in printf()-like statements when EINA_SLICE_FMT was used, it will print the slice mem and len.

Use with EINA_SLICE_FMT.

Note

This macro is usable with both Eina_Slice or Eina_Rw_Slice.

Parameters

[in]

s

The slice.

Returns

The arguments for an EINA_SLICE_FMT formatted printf.

Eina_Slice s = EINA_SLICE_STR_LITERAL("hello");
printf("s=" EINA_SLICE_FMT "\n", EINA_SLICE_PRINT(s));

Since

1.19

EINA_SLICE_FOREACH

#define EINA_SLICE_FOREACH	(		s,
			itr
	)

Value:

  for ((itr) = (s).mem; \
       (void *)(itr) < (void *)((s).bytes + (s).len); \
       (itr)++)

Iterate over the slice memory, using itr.

Each increment will be using the size of itr pointer (int32_t* will do in increments of 4 bytes).

Note

This macro is usable with both Eina_Slice or Eina_Rw_Slice.

Be aware of memory alignment! Accessing unaligned memory may not be supported in some architectures.

Parameters

[in]	s	The slice.
[in,out]	itr	the iterator to hold each byte. Use a proper type, not "void*" or "const void*" as it doesn't have an intrinsic size.

Since

1.19

Typedef Documentation

Eina_Slice

Eina_Slice

Defines a read-only memory region.

The slice is a memory starting at mem and accessible up to len bytes.

See also

Eina_Rw_Slice for read-write memory regions.

Since

1.19

Eina_Rw_Slice

Eina_Rw_Slice

Defines a read-and-write able memory region.

The slice is a memory starting at mem and accessible up to len bytes.

See also

Eina_Slice for read-only memory regions.

Since

1.19

Function Documentation

eina_rw_slice_slice_get()

static Eina_Slice eina_rw_slice_slice_get ( const Eina_Rw_Slice  rw_slice )

inlinestatic

Convert the Read-write slice to read-only.

Parameters

[in]

rw_slice

the read-write slice to convert.

Returns

the red-only slice matching the slice.

eina_slice_dup()

static Eina_Rw_Slice eina_slice_dup ( const Eina_Slice  slice )

inlinestatic

Creates a duplicate of slice's memory.

Parameters

[in]

slice

the input to duplicate

Returns

a new read-write slice with new mem that matches slice contents. The new mem is allocated with malloc() and must be released with free().

See also

eina_rw_slice_copy()

eina_rw_slice_dup()

Since

1.19

eina_rw_slice_dup()

static Eina_Rw_Slice eina_rw_slice_dup ( const Eina_Rw_Slice  rw_slice )

inlinestatic

Creates a duplicate of slice's memory.

Parameters

[in]

rw_slice

the input to duplicate

Returns

a new read-write slice with new mem that matches slice contents. The new mem is allocated with malloc() and must be released with free().

See also

eina_rw_slice_copy()

eina_slice_dup()

Since

1.19

eina_slice_compare()

static int eina_slice_compare ( const Eina_Slice  a, const Eina_Slice  b  )

inlinestatic

Compare two slices, similar to memcmp()

Parameters

[in]	a	the first slice to compare.
[in]	b	the second slice to compare.

Returns

0 if equal, < 0 if a < b, > 0 if a > b

Since

1.19

eina_rw_slice_compare()

static int eina_rw_slice_compare ( const Eina_Rw_Slice  a, const Eina_Rw_Slice  b  )

inlinestatic

Compare two slices, similar to memcmp()

Parameters

[in]	a	the first slice to compare.
[in]	b	the second slice to compare.

Returns

0 if equal, < 0 if a < b, > 0 if a > b

Since

1.19

eina_rw_slice_copy()

static Eina_Rw_Slice eina_rw_slice_copy ( const Eina_Rw_Slice  dest, const Eina_Slice  src  )

inlinestatic

Copy a read-only slice to a read-write one, similar to memcpy().

Parameters

[in]	dest	where to write the memory.
[in]	src	where to load memory.

Returns

a new slice with the resulting write. Note that the length (len) will be the smallest of dest and src.

See also

eina_rw_slice_dup()

eina_slice_dup()

Since

1.19

eina_slice_seek()

static Eina_Slice eina_slice_seek ( const Eina_Slice  slice, ssize_t  offset, int  whence  )

inlinestatic

Seek within a slice, similar to fseek().

Parameters

[in]	slice	the containing slice to seek inside.
[in]	offset	how to get to the new position.
[in]	whence	SEEK_SET, SEEK_END as fseek().

Returns

a new slice contained inside, it will start at the given offset and have a length that goes until the end of the slice. If an invalid whence, a zero-sized slice starting at slice mem will be returned. The slice is guaranteed to be contained within slice, even if offset causes it to go out of bounds, then it will be clamped to 0 and slice.len.

Since

1.19

eina_rw_slice_seek()

static Eina_Rw_Slice eina_rw_slice_seek ( const Eina_Rw_Slice  rw_slice, ssize_t  offset, int  whence  )

inlinestatic

Seek within a read-write slice, similar to fseek().

Parameters

[in]	rw_slice	the containing slice to seek inside.
[in]	offset	how to get to the new position.
[in]	whence	SEEK_SET, SEEK_END as fseek().

Returns

a new slice contained inside, it will start at the given offset and have a length that goes until the end of the rw_slice. If an invalid whence, a zero-sized slice starting at rw_slice mem will be returned. The slice is guaranteed to be contained within rw_slice, even if offset causes it to go out of bounds, then it will be clamped to 0 and slice.len.

Since

1.19

eina_slice_strchr()

static const void * eina_slice_strchr ( const Eina_Slice  slice, int  c  )

inlinestatic

Find a character inside the slice, similar to memchr().

Parameters

[in]	slice	the reference memory.
[in]	c	the byte (character) to find.

Returns

the memory within slice or NULL if not found.

Since

1.19

eina_slice_find()

static const void * eina_slice_find ( const Eina_Slice  slice, const Eina_Slice  needle  )

inlinestatic

Find a needle inside the slice, similar to memmem().

Parameters

[in]	slice	the reference memory.
[in]	needle	what to find.

Returns

the memory within slice or NULL if not found.

Since

1.19

eina_slice_startswith()

static Eina_Bool eina_slice_startswith ( const Eina_Slice  slice, const Eina_Slice  prefix  )

inlinestatic

Checks if the slice starts with a prefix.

Parameters

[in]	slice	the reference memory.
[in]	prefix	the slice to check if slice starts with.

Returns

EINA_TRUE if slice starts with prefix, EINA_FALSE otherwise.

Since

1.19

eina_slice_endswith()

static Eina_Bool eina_slice_endswith ( const Eina_Slice  slice, const Eina_Slice  suffix  )

inlinestatic

Checks if the slice ends with a suffix.

Parameters

[in]	slice	the reference memory.
[in]	suffix	the slice to check if slice ends with.

Returns

EINA_TRUE if slice ends with suffix, EINA_FALSE otherwise.

Since

1.19

eina_rw_slice_strchr()

static void * eina_rw_slice_strchr ( const Eina_Rw_Slice  rw_slice, int  c  )

inlinestatic

Find a character inside the slice, similar to memchr().

Parameters

[in]	rw_slice	the reference memory.
[in]	c	the byte (character) to find.

Returns

the memory within slice or NULL if not found.

Since

1.19

eina_rw_slice_find()

static void * eina_rw_slice_find ( const Eina_Rw_Slice  rw_slice, const Eina_Slice  needle  )

inlinestatic

Find a needle inside the slice, similar to memmem().

Parameters

[in]	rw_slice	the reference memory.
[in]	needle	what to find.

Returns

the memory within slice or NULL if not found.

Since

1.19

eina_rw_slice_startswith()

static Eina_Bool eina_rw_slice_startswith ( const Eina_Rw_Slice  slice, const Eina_Slice  prefix  )

inlinestatic

Checks if the slice starts with a prefix.

Parameters

[in]	slice	the reference memory.
[in]	prefix	the slice to check if slice starts with.

Returns

EINA_TRUE if slice starts with prefix, EINA_FALSE otherwise.

Since

1.19

eina_rw_slice_endswith()

static Eina_Bool eina_rw_slice_endswith ( const Eina_Rw_Slice  slice, const Eina_Slice  suffix  )

inlinestatic

Checks if the slice ends with a suffix.

Parameters

[in]	slice	the reference memory.
[in]	suffix	the slice to check if slice ends with.

Returns

EINA_TRUE if slice ends with suffix, EINA_FALSE otherwise.

Since

1.19

eina_slice_end_get()

static const void * eina_slice_end_get ( const Eina_Slice  slice )

inlinestatic

The memory position where the slice ends.

Note

this is out-of the slice, the first byte after it ends and must not be accessed.

Parameters

[in]

slice

the reference memory.

Returns

the first byte after the slice ends.

Since

1.19

eina_rw_slice_end_get()

static void * eina_rw_slice_end_get ( const Eina_Rw_Slice  rw_slice )

inlinestatic

The memory position where the slice ends.

Note

this is out-of the slice, the first byte after it ends and must not be accessed.

Parameters

[in]

rw_slice

the reference memory.

Returns

the first byte after the slice ends.

Since

1.19

eina_slice_strdup()

static char * eina_slice_strdup ( const Eina_Slice  slice )

inlinestatic

A null-terminated string for this slice.

Parameters

[in]

slice

the reference memory.

Returns

newly allocated memory or NULL on error

Since

1.19

eina_rw_slice_strdup()

static char * eina_rw_slice_strdup ( const Eina_Rw_Slice  rw_slice )

inlinestatic

A null-terminated string for this slice.

Parameters

[in]

rw_slice

the reference memory.

Returns

newly allocated memory or NULL on error

Since

1.19