Buffer's

Memory buffers. More...

Data Structures
struct	uv_buf_t
	A libuv buffer. More...

Macros
#define	using_buf(bufref)
	Use a buffer in a scope, freeing automatically when exiting. More...
#define	using_buf_on_abort_free(bufref)
	Use a buffer in a scope, freeing automatically only when an exception is thrown. More...
#define	using_buf_owned(owned, bufref)
	Use a potentially owned buffer in a scope. More...

Functions
uv_buf_t	nodec_buf (const void *base, size_t len)
	Initialize a libuv buffer, which is a record with a data pointer and its length.
uv_buf_t	nodec_buf_str (const char *s)
	Initialize a buffer from a string.
uv_buf_t	nodec_buf_strdup (const char *s)
	Initialize a buffer from a string. More...
uv_buf_t	nodec_buf_null ()
	Create a null buffer, i.e. nodec_buf(NULL,0).
uv_buf_t	nodec_buf_alloc (size_t len)
	Create and allocate a buffer of a certain length.
uv_buf_t	nodec_buf_realloc (uv_buf_t buf, size_t len)
	Reallocate a buffer to a given new length. More...
uv_buf_t	nodec_buf_ensure (uv_buf_t buf, size_t needed)
	Ensure a buffer has at least needed size. More...
uv_buf_t	nodec_buf_ensure_ex (uv_buf_t buf, size_t needed, size_t initial_size, size_t max_increase)
	Ensure a buffer has at least needed size. More...
uv_buf_t	nodec_buf_fit (uv_buf_t buf, size_t needed)
	Fit a buffer to needed size. More...
uv_buf_t	nodec_buf_append_into (uv_buf_t buf1, uv_buf_t buf2)
	Append the contents of buf2 into buf1. More...
bool	nodec_buf_is_null (uv_buf_t buf)
	Is this a null buffer?. More...
void	nodec_buf_free (uv_buf_t buf)
	Free a buffer. More...
void	nodec_bufref_free (uv_buf_t *buf)
	Free a buffer by reference. More...
void	nodec_bufref_freev (lh_value bufref)
	Free a buffer by reference value. More...
void	nodec_bufref_nofreev (lh_value pv)
	Don't free a buffer by reference value. More...

Detailed Description

Memory buffers.

Buffers are the libuv uv_buf_t` structure which contain a pointer to the data and their length. Buffer structures are small and always passed and returned by value.

The routines in this module ensure that all buffers actually are allocated with len + 1 where base[len] == 0, i.e. it is safe to print the contents as a string as it will be zero terminated.

---

Data Structure Documentation

uv_buf_t

struct uv_buf_t

A libuv buffer.

These are small and always passed by value.

Data Fields
void *	base	Pointer to the buffer data.
size_t	len	The length of the buffer data.

Macro Definition Documentation

using_buf

#define using_buf

(

bufref

)

Use a buffer in a scope, freeing automatically when exiting.

Pass the buffer by reference so it will free the final memory that bufref->base points to (and not the initial value).

Parameters

bufref

a reference to the buffer to free after use. Example uv_buf_t buf = async_read_buf(stream); {using_buf(&buf){ async_write_buf(out,buf); }}

using_buf_on_abort_free

#define using_buf_on_abort_free

(

bufref

)

Use a buffer in a scope, freeing automatically only when an exception is thrown.

Pass the buffer by reference so it will free the final memory that bufref->base points to (and not the initial value).

Parameters

bufref

a reference to the buffer to free after use.

using_buf_owned

#define using_buf_owned	(		owned,
			bufref
	)

Use a potentially owned buffer in a scope.

This is used for the async_read_bufx() calls where the returned buffer might be owned (and must be freed), or not (and must not be freed). Pass the buffer by reference so it will free the final memory that bufref->base points to (and not the initial value).

Parameters

owned	Only free the buffer if owned is true.
bufref	a reference to the buffer to free after use.

Function Documentation

nodec_buf_append_into()

uv_buf_t nodec_buf_append_into	(	uv_buf_t	buf1,
		uv_buf_t	buf2
	)

Append the contents of buf2 into buf1.

Parameters

buf1	the destination buffer.
buf2	the source buffer.

Returns

a potentially resized buf1 that contains the contents of both.

nodec_buf_ensure()

uv_buf_t nodec_buf_ensure	(	uv_buf_t	buf,
		size_t	needed
	)

Ensure a buffer has at least needed size.

Parameters

buf	The buffer to potentially reallocate. If buf is null, use 8kb for initial size, and after that use doubling of at most 4mb increments.
needed	the required size of the buffer.

Returns

a new buffer that has at least needed length.

nodec_buf_ensure_ex()

uv_buf_t nodec_buf_ensure_ex	(	uv_buf_t	buf,
		size_t	needed,
		size_t	initial_size,
		size_t	max_increase
	)

Ensure a buffer has at least needed size.

Like nodec_buf_ensure() but with customizable initial_size and max_increase.

nodec_buf_fit()

uv_buf_t nodec_buf_fit	(	uv_buf_t	buf,
		size_t	needed
	)

Fit a buffer to needed size.

Might increase the buffer size, or Reallocate to a smaller size if it was larger than 128 bytes with more than 20% wasted space.

Parameters

buf	the buffer to fit.
needed	the required space needed.

Returns

the new potentially reallocated buffer with a length that fits needed.

nodec_buf_free()

void nodec_buf_free

(

uv_buf_t

buf

)

Free a buffer.

This is usually not used directly, but through using_buf().

nodec_buf_is_null()

bool nodec_buf_is_null

(

uv_buf_t

buf

)

Is this a null buffer?.

Parameters

buf	the buffer.

Returns

true if the buffer length is 0 or the base is NULL.

nodec_buf_realloc()

uv_buf_t nodec_buf_realloc	(	uv_buf_t	buf,
		size_t	len
	)

Reallocate a buffer to a given new length.

See also nodec_buf_fit() and nodec_buf_ensure().

nodec_buf_strdup()

uv_buf_t nodec_buf_strdup

(

const char *

s

)

Initialize a buffer from a string.

This (re)allocates the string in the heap which is then owned by the buffer.

nodec_bufref_free()

void nodec_bufref_free

(

uv_buf_t *

buf

)

Free a buffer by reference.

This is usually not used directly, but through using_buf().

nodec_bufref_freev()

void nodec_bufref_freev

(

lh_value

bufref

)

Free a buffer by reference value.

This is usually not used directly, but through using_buf().

nodec_bufref_nofreev()

void nodec_bufref_nofreev

(

lh_value

pv

)

Don't free a buffer by reference value.

Usually not used directly, but used by using_buf_owned()