transmission/libtransmission/bencode.h

265 lines
8.2 KiB
C

/*
* This file Copyright (C) Mnemosyne LLC
*
* This file is licensed by the GPL version 2. Works owned by the
* Transmission project are granted a special exemption to clause 2(b)
* so that the bulk of its code can remain under the MIT license.
* This exemption does not extend to derived works not owned by
* the Transmission project.
*
* $Id$
*/
#ifndef TR_BENCODE_H
#define TR_BENCODE_H 1
#ifdef __cplusplus
extern "C" {
#endif
#include <inttypes.h> /* for int64_t */
struct evbuffer;
/**
* @addtogroup tr_benc Variant
*
* An object that acts like a union for
* integers, strings, lists, dictionaries, booleans, and floating-point numbers.
* The structure is named tr_benc due to the historical reason that it was
* originally tightly coupled with bencoded data. It currently supports
* being parsed from, and serialized to, both bencoded notation and json notation.
*
* @{
*/
/* these are PRIVATE IMPLEMENTATION details that should not be touched.
* I'll probably change them just to break your code! HA HA HA!
* it's included in the header for inlining and composition */
enum
{
TR_TYPE_INT = 1,
TR_TYPE_STR = 2,
TR_TYPE_LIST = 4,
TR_TYPE_DICT = 8,
TR_TYPE_BOOL = 16,
TR_TYPE_REAL = 32
};
/* These are PRIVATE IMPLEMENTATION details that should not be touched.
* I'll probably change them just to break your code! HA HA HA!
* it's included in the header for inlining and composition */
typedef struct tr_benc
{
union
{
uint8_t b; /* bool type */
double d; /* double type */
int64_t i; /* int type */
struct /* string type */
{
size_t len; /* the string length */
union {
char buf[16]; /* local buffer for short strings */
char * ptr; /* alloc'ed pointer for long strings */
} str;
} s;
struct /* list & dict types */
{
struct tr_benc * vals; /* nodes */
size_t alloc; /* nodes allocated */
size_t count; /* nodes used */
} l;
} val;
char type;
} tr_benc;
/***
****
***/
int tr_bencParse( const void * buf,
const void * bufend,
tr_benc * setme_benc,
const uint8_t ** setme_end );
int tr_bencLoad( const void * buf,
size_t buflen,
tr_benc * setme_benc,
char ** setme_end );
void tr_bencFree( tr_benc * );
void tr_bencInitStr( tr_benc *, const void * str, int str_len );
void tr_bencInitRaw( tr_benc *, const void * raw, size_t raw_len );
void tr_bencInitInt( tr_benc *, int64_t num );
int tr_bencInitDict( tr_benc *, size_t reserveCount );
int tr_bencInitList( tr_benc *, size_t reserveCount );
void tr_bencInitBool( tr_benc *, int value );
void tr_bencInitReal( tr_benc *, double value );
/***
**** Serialization / Deserialization
***/
typedef enum
{
TR_FMT_BENC,
TR_FMT_JSON,
TR_FMT_JSON_LEAN /* saves bandwidth by omitting all whitespace. */
}
tr_fmt_mode;
int tr_bencToFile( const tr_benc *, tr_fmt_mode, const char * filename );
char* tr_bencToStr( const tr_benc *, tr_fmt_mode, int * len );
struct evbuffer * tr_bencToBuf( const tr_benc *, tr_fmt_mode );
/* TR_FMT_JSON_LEAN and TR_FMT_JSON are equivalent in this function. */
int tr_bencLoadFile( tr_benc * setme, tr_fmt_mode, const char * filename );
/***
****
***/
int tr_bencListReserve( tr_benc *, size_t reserveCount );
tr_benc * tr_bencListAdd( tr_benc * );
tr_benc * tr_bencListAddBool( tr_benc *, bool val );
tr_benc * tr_bencListAddInt( tr_benc *, int64_t val );
tr_benc * tr_bencListAddReal( tr_benc *, double val );
tr_benc * tr_bencListAddStr( tr_benc *, const char * val );
tr_benc * tr_bencListAddRaw( tr_benc *, const uint8_t * val, size_t len );
tr_benc * tr_bencListAddList( tr_benc *, size_t reserveCount );
tr_benc * tr_bencListAddDict( tr_benc *, size_t reserveCount );
size_t tr_bencListSize( const tr_benc * list );
tr_benc * tr_bencListChild( tr_benc * list, size_t n );
int tr_bencListRemove( tr_benc *, size_t n );
/***
****
***/
int tr_bencDictReserve( tr_benc *, size_t reserveCount );
int tr_bencDictRemove( tr_benc *, const char * key );
tr_benc * tr_bencDictAdd( tr_benc *, const char * key );
tr_benc * tr_bencDictAddReal( tr_benc *, const char * key, double );
tr_benc * tr_bencDictAddInt( tr_benc *, const char * key, int64_t );
tr_benc * tr_bencDictAddBool( tr_benc *, const char * key, bool );
tr_benc * tr_bencDictAddStr( tr_benc *, const char * key, const char * );
tr_benc * tr_bencDictAddList( tr_benc *, const char * key, size_t reserve );
tr_benc * tr_bencDictAddDict( tr_benc *, const char * key, size_t reserve );
tr_benc * tr_bencDictAddRaw( tr_benc *, const char * key,
const void * raw, size_t rawlen );
bool tr_bencDictChild( tr_benc *, size_t i, const char ** key, tr_benc ** val );
tr_benc* tr_bencDictFind( tr_benc *, const char * key );
bool tr_bencDictFindList( tr_benc *, const char * key, tr_benc ** setme );
bool tr_bencDictFindDict( tr_benc *, const char * key, tr_benc ** setme );
bool tr_bencDictFindInt( tr_benc *, const char * key, int64_t * setme );
bool tr_bencDictFindReal( tr_benc *, const char * key, double * setme );
bool tr_bencDictFindBool( tr_benc *, const char * key, bool * setme );
bool tr_bencDictFindStr( tr_benc *, const char * key, const char ** setme );
bool tr_bencDictFindRaw( tr_benc *, const char * key,
const uint8_t ** setme_raw, size_t * setme_len );
/***
****
***/
/** @brief Get an int64_t from a variant object
@return true if successful, or false if the variant could not be represented as an int64_t */
bool tr_bencGetInt( const tr_benc * val, int64_t * setme );
/** @brief Get an string from a variant object
@return true if successful, or false if the variant could not be represented as a string */
bool tr_bencGetStr( const tr_benc * val, const char ** setme );
/** @brief Get a raw byte array from a variant object
@return true if successful, or false if the variant could not be represented as a raw byte array */
bool tr_bencGetRaw( const tr_benc * val, const uint8_t ** setme_raw, size_t * setme_len );
/** @brief Get a boolean from a variant object
@return true if successful, or false if the variant could not be represented as a boolean */
bool tr_bencGetBool( const tr_benc * val, bool * setme );
/** @brief Get a floating-point number from a variant object
@return true if successful, or false if the variant could not be represented as a floating-point number */
bool tr_bencGetReal( const tr_benc * val, double * setme );
static inline bool tr_bencIsType ( const tr_benc * b, int type ) { return ( b != NULL ) && ( b->type == type ); }
static inline bool tr_bencIsInt ( const tr_benc * b ) { return tr_bencIsType( b, TR_TYPE_INT ); }
static inline bool tr_bencIsDict ( const tr_benc * b ) { return tr_bencIsType( b, TR_TYPE_DICT ); }
static inline bool tr_bencIsList ( const tr_benc * b ) { return tr_bencIsType( b, TR_TYPE_LIST ); }
static inline bool tr_bencIsString( const tr_benc * b ) { return tr_bencIsType( b, TR_TYPE_STR ); }
static inline bool tr_bencIsBool ( const tr_benc * b ) { return tr_bencIsType( b, TR_TYPE_BOOL ); }
static inline bool tr_bencIsReal ( const tr_benc * b ) { return tr_bencIsType( b, TR_TYPE_REAL ); }
/** @brief Private function that's exposed here only for unit tests */
int tr_bencParseInt( const uint8_t * buf,
const uint8_t * bufend,
const uint8_t ** setme_end,
int64_t * setme_val );
/** @brief Private function that's exposed here only for unit tests */
int tr_bencParseStr( const uint8_t * buf,
const uint8_t * bufend,
const uint8_t ** setme_end,
const uint8_t ** setme_str,
size_t * setme_strlen );
/**
***
**/
/* this is only quasi-supported. don't rely on it too heavily outside of libT */
void tr_bencMergeDicts( tr_benc * target, const tr_benc * source );
/* @} */
#ifdef __cplusplus
}
#endif
#endif