Functions serialising and de-serialising session variables. The purpose of this is to allow the contents of session variables to be saved for later re-use. They may be saved in files, temporary tables or using some smart cache such as memcached (thru the pgmemcache add-in). More...

#include "postgres.h"
#include "veil_version.h"
#include "veil_funcs.h"
#include "veil_datatypes.h"

Functions
static int	streamlen (int bytes)
	Return the length of a base64 encoded stream for a binary stream of ::bytes length. More...

static int	hdrlen (char *name)
	Return the length of the header part of a serialised data stream for the given named variable. More...

static void	serialise_int4 (char **p_stream, int32 value)
	Serialise an int4 value as a base64 stream (truncated to save a byte) into *p_stream. More...

static int32	deserialise_int4 (char **p_stream)
	De-serialise an int4 value from a base64 character stream. More...

static void	serialise_stream (char *p_stream, int32 bytes, char instream)
	Serialise a binary stream as a base64 stream into *p_stream. More...

static void	deserialise_stream (char *p_stream, int32 bytes, char outstream)
	De-serialise a binary stream. More...

static void	serialise_bool (char **p_stream, bool value)
	Serialise a boolean value into *p_stream. More...

static bool	deserialise_bool (char **p_stream)
	De-serialise a boolean value. More...

static void	serialise_char (char **p_stream, char value)
	Serialise a character value into *p_stream. More...

static char	deserialise_char (char **p_stream)
	De-serialise a character value. More...

static void	serialise_name (char *p_stream, char name)
	Serialise a string (containing a name) into *p_stream. More...

static char *	deserialise_name (char **p_stream)
	De-serialise a string returning a dynamically allocated string. More...

static char *	serialise_int4var (Int4Var var, char name)
	Serialise a veil integer variable into a dynamically allocated string. More...

static VarEntry *	deserialise_int4var (char **p_stream)
	De-serialise a veil integer variable. More...

static char *	serialise_int4array (Int4Array array, char name)
	Serialise a veil integer array variable into a dynamically allocated string. More...

static VarEntry *	deserialise_int4array (char **p_stream)
	De-serialise a veil integer array variable. More...

static char *	serialise_range (Range range, char name)
	Serialise a veil range variable into a dynamically allocated string. More...

static VarEntry *	deserialise_range (char **p_stream)
	De-serialise a veil range variable. More...

static void	serialise_one_bitmap (char *p_stream, Bitmap bitmap)
	Serialise a single bitmap from a veil bitmap array or bitmap hash. More...

static char *	serialise_bitmap (Bitmap bitmap, char name)
	Serialise a veil bitmap variable into a dynamically allocated string. More...

static void	deserialise_one_bitmap (Bitmap *p_bitmap, char name, bool shared, char **p_stream)
	De-serialise a single bitmap into a veil bitmap array or bitmap hash. More...

static VarEntry *	deserialise_bitmap (char **p_stream)
	De-serialise a veil bitmap variable. More...

static char *	serialise_bitmap_array (BitmapArray bmarray, char name)
	Serialise a veil bitmap array variable into a dynamically allocated string. More...

static VarEntry *	deserialise_bitmap_array (char **p_stream)
	De-serialise a veil bitmap array variable. More...

static int	sizeof_bitmaps_in_hash (BitmapHash *bmhash, int bitset_size)
	Calculate the size needed for a base64 stream to contain all of the bitmaps in a bitmap hash including their keys. More...

static char *	serialise_bitmap_hash (BitmapHash bmhash, char name)
	Serialise a veil bitmap hash variable into a dynamically allocated string. More...

static VarEntry *	deserialise_bitmap_hash (char **p_stream)
	De-serialise a veil bitmap hash variable. More...

char *	vl_serialise_var (char *name)
	Serialise a veil variable. More...

VarEntry *	vl_deserialise_next (char **p_stream)
	De-serialise the next veil variable from *p_stream. More...

int32	vl_deserialise (char **p_stream)
	De-serialise a base64 string containing, possibly many, derialised veil variables. More...

Detailed Description

Functions serialising and de-serialising session variables. The purpose of this is to allow the contents of session variables to be saved for later re-use. They may be saved in files, temporary tables or using some smart cache such as memcached (thru the pgmemcache add-in).

Author:       Marc Munro
Copyright (c) 2009 - 2011 Marc Munro
License:      BSD

Definition in file veil_serialise.c.

Function Documentation

◆ streamlen()

static int streamlen ( int bytes )

static

Return the length of a base64 encoded stream for a binary stream of ::bytes length.

Parameters

bytes The length of the input binary stream in bytes

Returns: The length of the base64 character stream required to represent the input stream.

Definition at line 197 of file veil_serialise.c.

Referenced by deserialise_stream(), serialise_bitmap(), serialise_bitmap_array(), serialise_bitmap_hash(), and serialise_int4array().

◆ hdrlen()

static int hdrlen ( char * name )

static

Return the length of the header part of a serialised data stream for the given named variable.

Note that the header contains the name and a base64 encode length indicator for the name.

Parameters

name	The variable name to be recorded in the header

Returns: The length of the base64 character stream required to hold the serialised header for the named variable.

Definition at line 212 of file veil_serialise.c.

Referenced by serialise_bitmap(), serialise_bitmap_array(), serialise_bitmap_hash(), serialise_int4array(), serialise_int4var(), serialise_range(), and sizeof_bitmaps_in_hash().

◆ serialise_int4()

static void serialise_int4	(	char **	p_stream,
		int32	value
	)

static

Serialise an int4 value as a base64 stream (truncated to save a byte) into *p_stream.

Parameters

p_stream	Pointer into stream currently being written. This must be large enought to take the contents to be written. This pointer is updated to point to the next free slot in the stream after writing the int4 value, and is null terminated at that position.
value	The value to be written to the stream.

Definition at line 229 of file veil_serialise.c.

Referenced by serialise_bitmap_array(), serialise_bitmap_hash(), serialise_int4array(), serialise_int4var(), serialise_name(), serialise_one_bitmap(), and serialise_range().

◆ deserialise_int4()

static int32 deserialise_int4 ( char ** p_stream )

static

De-serialise an int4 value from a base64 character stream.

Parameters

p_stream Pointer into the stream currently being read. must be large enought to take the contents to be written. This pointer is updated to point to the next free slot in the stream after reading the int4 value.

Returns: the int4 value read from the stream

Definition at line 247 of file veil_serialise.c.

Referenced by deserialise_bitmap_array(), deserialise_bitmap_hash(), deserialise_int4array(), deserialise_name(), and deserialise_one_bitmap().

◆ serialise_stream()

static void serialise_stream	(	char **	p_stream,
		int32	bytes,
		char *	instream
	)

static

Serialise a binary stream as a base64 stream into *p_stream.

Parameters

p_stream	Pointer into stream currently being written. This pointer is updated to point to the next free slot in the stream after writing the contents of instream and is null terminated at that position.
bytes	The number of bytes to be written.
instream	The binary stream to be written.

Definition at line 309 of file veil_serialise.c.

Referenced by serialise_int4array(), and serialise_one_bitmap().

◆ deserialise_stream()

static void deserialise_stream	(	char **	p_stream,
		int32	bytes,
		char *	outstream
	)

static

De-serialise a binary stream.

Parameters

p_stream	Pointer into the stream currently being read. pointer is updated to point to the next free slot in the stream after reading the stream.
bytes	The number of bytes to be read
outstream	Pointer into the pre-allocated memory are into which the binary from p_stream is to be written.

Definition at line 327 of file veil_serialise.c.

References streamlen().

◆ serialise_bool()

static void serialise_bool	(	char **	p_stream,
		bool	value
	)

static

Serialise a boolean value into *p_stream.

Parameters

p_stream	Pointer into stream currently being written. This pointer is updated to point to the next free slot in the stream after writing the contents of value and is null terminated at that position. A true value is written as 'T', and false as 'F'.
value	The boolean value to be written.

Definition at line 345 of file veil_serialise.c.

Referenced by serialise_int4var().

◆ deserialise_bool()

static bool deserialise_bool ( char ** p_stream )

static

De-serialise a boolean value.

Parameters

p_stream Pointer into the stream currently being read. pointer is updated to point to the next free slot in the stream after reading the stream.

Returns: True or false depending on the contents of p_stream.

Definition at line 361 of file veil_serialise.c.

◆ serialise_char()

static void serialise_char	(	char **	p_stream,
		char	value
	)

static

Serialise a character value into *p_stream.

Parameters

p_stream	Pointer into stream currently being written. This pointer is updated to point to the next free slot in the stream after writing the contents of value and is null terminated at that position. The character is written as a single byte character.
value	The character value to be written.

Definition at line 379 of file veil_serialise.c.

Referenced by serialise_bitmap(), serialise_bitmap_array(), serialise_bitmap_hash(), serialise_int4array(), serialise_int4var(), and serialise_range().

◆ deserialise_char()

static char deserialise_char ( char ** p_stream )

static

De-serialise a character value.

Parameters

p_stream Pointer into the stream currently being read. pointer is updated to point to the next free slot in the stream after reading the stream.

Returns: The value of the character read from p_stream.

Definition at line 395 of file veil_serialise.c.

Referenced by vl_deserialise_next().

◆ serialise_name()

static void serialise_name	(	char **	p_stream,
		char *	name
	)

static

Serialise a string (containing a name) into *p_stream.

Parameters

p_stream	Pointer into stream currently being written. This pointer is updated to point to the next free slot in the stream after writing the contents of value and is null terminated at that position. The character is written as a single byte character.
name	The string to be written.

Definition at line 413 of file veil_serialise.c.

References serialise_int4().

Referenced by serialise_bitmap(), serialise_bitmap_array(), serialise_bitmap_hash(), serialise_int4array(), serialise_int4var(), and serialise_range().

◆ deserialise_name()

static char* deserialise_name ( char ** p_stream )

static

De-serialise a string returning a dynamically allocated string.

Parameters

p_stream Pointer into the stream currently being read. pointer is updated to point to the next free slot in the stream after reading the stream.

Returns: Dynamically allocated copy of string read from *p_stream

Definition at line 439 of file veil_serialise.c.

References deserialise_int4().

Referenced by deserialise_bitmap(), deserialise_bitmap_array(), deserialise_bitmap_hash(), deserialise_int4array(), deserialise_int4var(), and deserialise_range().

◆ serialise_int4var()

static char* serialise_int4var	(	Int4Var *	var,
		char *	name
	)

static

Serialise a veil integer variable into a dynamically allocated string.

Parameters

var	Pointer to the variable to be serialised
name	The name of the variable

Returns: Dynamically allocated string containing the serialised variable

Definition at line 458 of file veil_serialise.c.

References hdrlen(), Int4Var::isnull, serialise_bool(), serialise_char(), serialise_int4(), serialise_name(), and Int4Var::value.

◆ deserialise_int4var()

static VarEntry* deserialise_int4var ( char ** p_stream )

static

De-serialise a veil integer variable.

Parameters

**p_stream Pointer into the stream currently being read. pointer is updated to point to the next free slot in the stream after reading the stream

Returns: Pointer to the variable created or updated from the stream.

Definition at line 480 of file veil_serialise.c.

References deserialise_name(), VarEntry::obj, Int4Var::type, and vl_lookup_variable().

Referenced by vl_deserialise_next().

◆ serialise_int4array()

static char* serialise_int4array	(	Int4Array *	array,
		char *	name
	)

static

Serialise a veil integer array variable into a dynamically allocated string.

Parameters

array	Pointer to the variable to be serialised
name	The name of the variable

Returns: Dynamically allocated string containing the serialised variable

Definition at line 510 of file veil_serialise.c.

References Int4Array::array, Int4Array::arraymax, Int4Array::arrayzero, hdrlen(), serialise_char(), serialise_int4(), serialise_name(), serialise_stream(), and streamlen().

◆ deserialise_int4array()

static VarEntry* deserialise_int4array ( char ** p_stream )

static

De-serialise a veil integer array variable.

Parameters

**p_stream Pointer into the stream currently being read. pointer is updated to point to the next free slot in the stream after reading the stream

Returns: Pointer to the variable created or updated from the stream.

Definition at line 537 of file veil_serialise.c.

References deserialise_int4(), deserialise_name(), VarEntry::obj, Int4Array::type, and vl_lookup_variable().

Referenced by vl_deserialise_next().

◆ serialise_range()

static char* serialise_range	(	Range *	range,
		char *	name
	)

static

Serialise a veil range variable into a dynamically allocated string.

Parameters

range	Pointer to the variable to be serialised
name	The name of the variable

Returns: Dynamically allocated string containing the serialised variable

Definition at line 573 of file veil_serialise.c.

References hdrlen(), Range::max, Range::min, serialise_char(), serialise_int4(), and serialise_name().

◆ deserialise_range()

static VarEntry* deserialise_range ( char ** p_stream )

static

De-serialise a veil range variable.

Parameters

**p_stream Pointer into the stream currently being read. pointer is updated to point to the next free slot in the stream after reading the stream

Returns: Pointer to the variable created or updated from the stream.

Definition at line 595 of file veil_serialise.c.

References deserialise_name(), VarEntry::obj, Range::type, and vl_lookup_variable().

Referenced by vl_deserialise_next().

◆ serialise_one_bitmap()

static void serialise_one_bitmap	(	char **	p_stream,
		Bitmap *	bitmap
	)

static

Serialise a single bitmap from a veil bitmap array or bitmap hash.

Parameters

p_stream	Pointer into the stream currently being read. pointer is updated to point to the next free slot in the stream after writing the stream.
bitmap	The bitmap to be serialised.

Definition at line 625 of file veil_serialise.c.

References ARRAYELEMS, Bitmap::bitmax, Bitmap::bitset, Bitmap::bitzero, serialise_int4(), and serialise_stream().

Referenced by serialise_bitmap(), serialise_bitmap_array(), and serialise_bitmap_hash().

◆ serialise_bitmap()

static char* serialise_bitmap	(	Bitmap *	bitmap,
		char *	name
	)

static

Serialise a veil bitmap variable into a dynamically allocated string.

Parameters

bitmap	Pointer to the variable to be serialised
name	The name of the variable

Returns: Dynamically allocated string containing the serialised variable

Definition at line 644 of file veil_serialise.c.

References ARRAYELEMS, Bitmap::bitmax, Bitmap::bitzero, hdrlen(), serialise_char(), serialise_name(), serialise_one_bitmap(), and streamlen().

◆ deserialise_one_bitmap()

static void deserialise_one_bitmap	(	Bitmap **	p_bitmap,
		char *	name,
		bool	shared,
		char **	p_stream
	)

static

De-serialise a single bitmap into a veil bitmap array or bitmap hash.

Parameters

p_bitmap	Pointer to bitmap pointer. This may be updated to contain a dynamically allocated bitmap if none is already present.
name	The name of the variable, for error reporting purposes.
shared	Whether the bitmap is part of a shared rather than session variable.
p_stream	Pointer into the stream currently being read. pointer is updated to point to the next free slot in the stream after reading the stream.

Definition at line 671 of file veil_serialise.c.

References ARRAYELEMS, deserialise_int4(), and Bitmap::type.

Referenced by deserialise_bitmap().

◆ deserialise_bitmap()

static VarEntry* deserialise_bitmap ( char ** p_stream )

static

De-serialise a veil bitmap variable.

Parameters

**p_stream Pointer into the stream currently being read. pointer is updated to point to the next free slot in the stream after reading the stream

Returns: Pointer to the variable created or updated from the stream.

Definition at line 706 of file veil_serialise.c.

References deserialise_name(), deserialise_one_bitmap(), VarEntry::obj, VarEntry::shared, and vl_lookup_variable().

Referenced by vl_deserialise_next().

◆ serialise_bitmap_array()

static char* serialise_bitmap_array	(	BitmapArray *	bmarray,
		char *	name
	)

static

Serialise a veil bitmap array variable into a dynamically allocated string.

Parameters

bmarray	Pointer to the variable to be serialised
name	The name of the variable

Returns: Dynamically allocated string containing the serialised variable

Definition at line 727 of file veil_serialise.c.

References ARRAYELEMS, BitmapArray::arraymax, BitmapArray::arrayzero, BitmapArray::bitmap, BitmapArray::bitmax, BitmapArray::bitzero, hdrlen(), serialise_char(), serialise_int4(), serialise_name(), serialise_one_bitmap(), and streamlen().

◆ deserialise_bitmap_array()

static VarEntry* deserialise_bitmap_array ( char ** p_stream )

static

De-serialise a veil bitmap array variable.

Parameters

**p_stream Pointer into the stream currently being read. pointer is updated to point to the next free slot in the stream after reading the stream

Returns: Pointer to the variable created or updated from the stream.

Definition at line 760 of file veil_serialise.c.

References deserialise_int4(), deserialise_name(), VarEntry::obj, BitmapArray::type, and vl_lookup_variable().

Referenced by vl_deserialise_next().

◆ sizeof_bitmaps_in_hash()

static int sizeof_bitmaps_in_hash	(	BitmapHash *	bmhash,
		int	bitset_size
	)

static

Calculate the size needed for a base64 stream to contain all of the bitmaps in a bitmap hash including their keys.

Parameters

bmhash	Pointer to the variable to be serialised
bitset_size	The size, in bytes, of each bitset in the bitmap hash.

Returns: Number of bytes required to contain all of the bitmaps and keys in the bitmap_hash

Definition at line 808 of file veil_serialise.c.

References BitmapHash::hash, hdrlen(), VarEntry::key, and vl_NextHashEntry().

Referenced by serialise_bitmap_hash().

◆ serialise_bitmap_hash()

static char* serialise_bitmap_hash	(	BitmapHash *	bmhash,
		char *	name
	)

static

Serialise a veil bitmap hash variable into a dynamically allocated string.

Parameters

bmhash	Pointer to the variable to be serialised
name	The name of the variable

Returns: Dynamically allocated string containing the serialised variable

Definition at line 831 of file veil_serialise.c.

References ARRAYELEMS, BitmapHash::bitmax, BitmapHash::bitzero, BitmapHash::hash, hdrlen(), VarEntry::key, VarEntry::obj, serialise_char(), serialise_int4(), serialise_name(), serialise_one_bitmap(), sizeof_bitmaps_in_hash(), streamlen(), and vl_NextHashEntry().

◆ deserialise_bitmap_hash()

static VarEntry* deserialise_bitmap_hash ( char ** p_stream )

static

De-serialise a veil bitmap hash variable.

Parameters

**p_stream Pointer into the stream currently being read. pointer is updated to point to the next free slot in the stream after reading the stream

Returns: Pointer to the variable created or updated from the stream.

Definition at line 866 of file veil_serialise.c.

References deserialise_int4(), deserialise_name(), VarEntry::obj, BitmapHash::type, and vl_lookup_variable().

Referenced by vl_deserialise_next().

◆ vl_serialise_var()

char* vl_serialise_var ( char * name )

Serialise a veil variable.

Parameters

name	The name of the variable to be serialised.

Returns: Dynamically allocated string containing the serialised value.

Definition at line 911 of file veil_serialise.c.

References VarEntry::obj, Object::type, and vl_lookup_variable().

Referenced by veil_serialise().

◆ vl_deserialise_next()

VarEntry* vl_deserialise_next ( char ** p_stream )

De-serialise the next veil variable from *p_stream.

Parameters

**p_stream Pointer into the stream currently being read. pointer is updated to point to the next free slot in the stream after reading the stream

Returns: The deserialised variable.

Definition at line 958 of file veil_serialise.c.

References deserialise_bitmap(), deserialise_bitmap_array(), deserialise_bitmap_hash(), deserialise_char(), deserialise_int4array(), deserialise_int4var(), and deserialise_range().

Referenced by vl_deserialise().

◆ vl_deserialise()

int32 vl_deserialise ( char ** p_stream )

De-serialise a base64 string containing, possibly many, derialised veil variables.

Parameters

**p_stream Pointer into the stream currently being read.

Returns: A count of the number of variables that have been de-serialised.

Definition at line 996 of file veil_serialise.c.

References vl_deserialise_next().

Referenced by veil_deserialise().