Libparserutils
codec_ascii.c File Reference
#include <assert.h>
#include <stdlib.h>
#include <string.h>
#include <parserutils/charset/mibenum.h>
#include "charset/codecs/codec_impl.h"
#include "utils/endian.h"
#include "utils/utils.h"

Go to the source code of this file.

Data Structures

struct  charset_ascii_codec
 US-ASCII charset codec. More...
 

Macros

#define READ_BUFSIZE   (8)
 
#define WRITE_BUFSIZE   (8)
 

Typedefs

typedef struct charset_ascii_codec charset_ascii_codec
 US-ASCII charset codec.
 

Functions

static bool charset_ascii_codec_handles_charset (const char *charset)
 Determine whether this codec handles a specific charset.
 
static parserutils_error charset_ascii_codec_create (const char *charset, parserutils_charset_codec **codec)
 Create a US-ASCII codec.
 
static parserutils_error charset_ascii_codec_destroy (parserutils_charset_codec *codec)
 Destroy a US-ASCII codec.
 
static parserutils_error charset_ascii_codec_encode (parserutils_charset_codec *codec, const uint8_t **source, size_t *sourcelen, uint8_t **dest, size_t *destlen)
 Encode a chunk of UCS-4 (big endian) data into US-ASCII.
 
static parserutils_error charset_ascii_codec_decode (parserutils_charset_codec *codec, const uint8_t **source, size_t *sourcelen, uint8_t **dest, size_t *destlen)
 Decode a chunk of US-ASCII data into UCS-4 (big endian)
 
static parserutils_error charset_ascii_codec_reset (parserutils_charset_codec *codec)
 Clear a US-ASCII codec's encoding state.
 
static parserutils_error charset_ascii_codec_read_char (charset_ascii_codec *c, const uint8_t **source, size_t *sourcelen, uint8_t **dest, size_t *destlen)
 Read a character from US-ASCII to UCS-4 (big endian)
 
static parserutils_error charset_ascii_codec_output_decoded_char (charset_ascii_codec *c, uint32_t ucs4, uint8_t **dest, size_t *destlen)
 Output a UCS-4 character (big endian)
 
static parserutils_error charset_ascii_from_ucs4 (charset_ascii_codec *c, uint32_t ucs4, uint8_t **s, size_t *len)
 Convert a UCS4 (host endian) character to US-ASCII.
 
static parserutils_error charset_ascii_to_ucs4 (charset_ascii_codec *c, const uint8_t *s, size_t len, uint32_t *ucs4)
 Convert a US-ASCII character to UCS4 (host endian)
 

Variables

const parserutils_charset_handler charset_ascii_codec_handler
 

Macro Definition Documentation

◆ READ_BUFSIZE

#define READ_BUFSIZE   (8)

Definition at line 24 of file codec_ascii.c.

◆ WRITE_BUFSIZE

#define WRITE_BUFSIZE   (8)

Definition at line 30 of file codec_ascii.c.

Typedef Documentation

◆ charset_ascii_codec

typedef struct charset_ascii_codec charset_ascii_codec

US-ASCII charset codec.

Function Documentation

◆ charset_ascii_codec_create()

parserutils_error charset_ascii_codec_create ( const char * charset,
parserutils_charset_codec ** codec )
static

◆ charset_ascii_codec_decode()

parserutils_error charset_ascii_codec_decode ( parserutils_charset_codec * codec,
const uint8_t ** source,
size_t * sourcelen,
uint8_t ** dest,
size_t * destlen )
static

Decode a chunk of US-ASCII data into UCS-4 (big endian)

Parameters
codecThe codec to use
sourcePointer to pointer to source data
sourcelenPointer to length (in bytes) of source data
destPointer to pointer to output buffer
destlenPointer to length (in bytes) of output buffer
Returns
PARSERUTILS_OK on success, PARSERUTILS_NOMEM if output buffer is too small, PARSERUTILS_INVALID if a character cannot be represented and the codec's error handling mode is set to STRICT,

On exit, ::source will point immediately after the last input character read, if the result is _OK or _NOMEM. Any remaining output for the character will be buffered by the codec for writing on the next call.

In the case of the result being INVALID, ::source will point _at the last input character read; nothing will be written or buffered for the failed character. It is up to the client to fix the cause of the failure and retry the decoding process.

Note that, if failure occurs whilst attempting to write any output buffered by the last call, then ::source and ::sourcelen will remain unchanged (as nothing more has been read).

If STRICT error handling is configured and an illegal sequence is split over two calls, then _INVALID will be returned from the second call, but ::source will point mid-way through the invalid sequence (i.e. it will be unmodified over the second call). In addition, the internal incomplete-sequence buffer will be emptied, such that subsequent calls will progress, rather than re-evaluating the same invalid sequence.

::sourcelen will be reduced appropriately on exit.

::dest will point immediately after the last character written.

::destlen will be reduced appropriately on exit.

Call this with a source length of 0 to flush the output buffer.

Definition at line 284 of file codec_ascii.c.

References charset_ascii_codec_read_char(), endian_host_to_big(), PARSERUTILS_NOMEM, PARSERUTILS_OK, charset_ascii_codec::read_buf, and charset_ascii_codec::read_len.

Referenced by charset_ascii_codec_create().

◆ charset_ascii_codec_destroy()

parserutils_error charset_ascii_codec_destroy ( parserutils_charset_codec * codec)
static

Destroy a US-ASCII codec.

Parameters
codecThe codec to destroy
Returns
PARSERUTILS_OK on success, appropriate error otherwise

Definition at line 131 of file codec_ascii.c.

References PARSERUTILS_OK, and UNUSED.

Referenced by charset_ascii_codec_create().

◆ charset_ascii_codec_encode()

parserutils_error charset_ascii_codec_encode ( parserutils_charset_codec * codec,
const uint8_t ** source,
size_t * sourcelen,
uint8_t ** dest,
size_t * destlen )
static

Encode a chunk of UCS-4 (big endian) data into US-ASCII.

Parameters
codecThe codec to use
sourcePointer to pointer to source data
sourcelenPointer to length (in bytes) of source data
destPointer to pointer to output buffer
destlenPointer to length (in bytes) of output buffer
Returns
PARSERUTILS_OK on success, PARSERUTILS_NOMEM if output buffer is too small, PARSERUTILS_INVALID if a character cannot be represented and the codec's error handling mode is set to STRICT,

On exit, ::source will point immediately after the last input character read. Any remaining output for the character will be buffered by the codec for writing on the next call.

Note that, if failure occurs whilst attempting to write any output buffered by the last call, then ::source and ::sourcelen will remain unchanged (as nothing more has been read).

::sourcelen will be reduced appropriately on exit.

::dest will point immediately after the last character written.

::destlen will be reduced appropriately on exit.

Definition at line 165 of file codec_ascii.c.

References charset_ascii_from_ucs4(), endian_big_to_host(), len, PARSERUTILS_NOMEM, PARSERUTILS_OK, charset_ascii_codec::write_buf, WRITE_BUFSIZE, and charset_ascii_codec::write_len.

Referenced by charset_ascii_codec_create().

◆ charset_ascii_codec_handles_charset()

bool charset_ascii_codec_handles_charset ( const char * charset)
static

Determine whether this codec handles a specific charset.

Parameters
charsetCharset to test
Returns
true if handleable, false otherwise

Definition at line 71 of file codec_ascii.c.

References parserutils_charset_mibenum_from_name(), and SLEN.

◆ charset_ascii_codec_output_decoded_char()

parserutils_error charset_ascii_codec_output_decoded_char ( charset_ascii_codec * c,
uint32_t ucs4,
uint8_t ** dest,
size_t * destlen )
inlinestatic

Output a UCS-4 character (big endian)

Parameters
cCodec to use
ucs4UCS-4 character (host endian)
destPointer to pointer to output buffer
destlenPointer to output buffer length
Returns
PARSERUTILS_OK on success, PARSERUTILS_NOMEM if output buffer is too small,

Definition at line 435 of file codec_ascii.c.

References endian_host_to_big(), PARSERUTILS_NOMEM, PARSERUTILS_OK, charset_ascii_codec::read_buf, and charset_ascii_codec::read_len.

Referenced by charset_ascii_codec_read_char().

◆ charset_ascii_codec_read_char()

parserutils_error charset_ascii_codec_read_char ( charset_ascii_codec * c,
const uint8_t ** source,
size_t * sourcelen,
uint8_t ** dest,
size_t * destlen )
inlinestatic

Read a character from US-ASCII to UCS-4 (big endian)

Parameters
cThe codec
sourcePointer to pointer to source buffer (updated on exit)
sourcelenPointer to length of source buffer (updated on exit)
destPointer to pointer to output buffer (updated on exit)
destlenPointer to length of output buffer (updated on exit)
Returns
PARSERUTILS_OK on success, PARSERUTILS_NOMEM if output buffer is too small, PARSERUTILS_INVALID if a character cannot be represented and the codec's error handling mode is set to STRICT,

On exit, ::source will point immediately after the last input character read, if the result is _OK or _NOMEM. Any remaining output for the character will be buffered by the codec for writing on the next call.

In the case of the result being INVALID, ::source will point _at the last input character read; nothing will be written or buffered for the failed character. It is up to the client to fix the cause of the failure and retry the decoding process.

::sourcelen will be reduced appropriately on exit.

::dest will point immediately after the last character written.

::destlen will be reduced appropriately on exit.

Definition at line 378 of file codec_ascii.c.

References charset_ascii_codec::base, charset_ascii_codec_output_decoded_char(), charset_ascii_to_ucs4(), parserutils_charset_codec::errormode, PARSERUTILS_CHARSET_CODEC_ERROR_STRICT, PARSERUTILS_INVALID, PARSERUTILS_NEEDDATA, PARSERUTILS_NOMEM, and PARSERUTILS_OK.

Referenced by charset_ascii_codec_decode().

◆ charset_ascii_codec_reset()

parserutils_error charset_ascii_codec_reset ( parserutils_charset_codec * codec)
static

Clear a US-ASCII codec's encoding state.

Parameters
codecThe codec to reset
Returns
PARSERUTILS_OK on success, appropriate error otherwise

Definition at line 336 of file codec_ascii.c.

References PARSERUTILS_OK, charset_ascii_codec::read_buf, charset_ascii_codec::read_len, charset_ascii_codec::write_buf, and charset_ascii_codec::write_len.

Referenced by charset_ascii_codec_create().

◆ charset_ascii_from_ucs4()

parserutils_error charset_ascii_from_ucs4 ( charset_ascii_codec * c,
uint32_t ucs4,
uint8_t ** s,
size_t * len )
inlinestatic

Convert a UCS4 (host endian) character to US-ASCII.

Parameters
cThe codec instance
ucs4The UCS4 character to convert
sPointer to pointer to destination buffer
lenPointer to destination buffer length
Returns
PARSERUTILS_OK on success, PARSERUTILS_NOMEM if there's insufficient space in the output buffer, PARSERUTILS_INVALID if the character cannot be represented

_INVALID will only be returned if the codec's conversion mode is STRICT. Otherwise, '?' will be output.

On successful conversion, *s and *len will be updated.

Definition at line 470 of file codec_ascii.c.

References charset_ascii_codec::base, parserutils_charset_codec::errormode, len, PARSERUTILS_CHARSET_CODEC_ERROR_STRICT, PARSERUTILS_INVALID, PARSERUTILS_NOMEM, and PARSERUTILS_OK.

Referenced by charset_ascii_codec_encode().

◆ charset_ascii_to_ucs4()

parserutils_error charset_ascii_to_ucs4 ( charset_ascii_codec * c,
const uint8_t * s,
size_t len,
uint32_t * ucs4 )
inlinestatic

Convert a US-ASCII character to UCS4 (host endian)

Parameters
cThe codec instance
sPointer to source buffer
lenSource buffer length
ucs4Pointer to destination buffer
Returns
PARSERUTILS_OK on success, PARSERUTILS_NEEDDATA if there's insufficient input data PARSERUTILS_INVALID if the character cannot be represented

Definition at line 506 of file codec_ascii.c.

References len, PARSERUTILS_INVALID, PARSERUTILS_NEEDDATA, PARSERUTILS_OK, and UNUSED.

Referenced by charset_ascii_codec_read_char().

Variable Documentation

◆ charset_ascii_codec_handler

const parserutils_charset_handler charset_ascii_codec_handler
Initial value:
= {
}
static parserutils_error charset_ascii_codec_create(const char *charset, parserutils_charset_codec **codec)
Create a US-ASCII codec.
Definition codec_ascii.c:97
static bool charset_ascii_codec_handles_charset(const char *charset)
Determine whether this codec handles a specific charset.
Definition codec_ascii.c:71

Definition at line 527 of file codec_ascii.c.