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(encode_coding_utf_8): Initialize produced_chars to 0.

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(decode_coding_utf_16): Fix converting high and low bytes to
code-point.
(encode_coding_utf_16): Substitute coding->default_char for
non-Unicode characters.
(decode_coding): Don't call record_insert here.
(setup_coding_system): Initialize `surrogate' of
coding->spec.utf_16 to 0.
(EMIT_ONE_BYTE): Fix for multibyte case.
This commit is contained in:
Kenichi Handa 2002-03-08 00:19:39 +00:00
parent ed9d8bdadc
commit e19c3639af
1 changed files with 57 additions and 50 deletions
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107
src/coding.c
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@ -46,31 +46,23 @@ Boston, MA 02111-1307, USA. */
CODING SYSTEM
Coding system is an encoding mechanism of one or more character
sets. Here's a list of coding system types supported by Emacs.
When we say "decode", it means converting a text encoded by some
coding system into Emacs' internal format (emacs-utf-8), and when we
say "encode", it means converting a text of emacs-utf-8 to some
other coding system.
Coding system is an object for a encoding mechanism that contains
information about how to convert byte sequence to character
sequences and vice versa. When we say "decode", it means converting
a byte sequence of a specific coding system into a character
sequence that is represented by Emacs' internal coding system
`emacs-utf-8', and when we say "encode", it means converting a
character sequence of emacs-utf-8 to a byte sequence of a specific
coding system.
Emacs represents a coding system by a Lisp symbol. Each symbol is a
key to the hash table Vcharset_hash_table. This hash table
associates the symbol to the corresponding detailed specifications.
In Emacs Lisp, a coding system is represented by a Lisp symbol. In
C level, a coding system is represented by a vector of attributes
stored in the hash table Vcharset_hash_table. The conversion from a
coding system symbol to attributes vector is done by looking up
Vcharset_hash_table by the symbol.
Before using a coding system for decoding and encoding, we setup a
structure of type `struct coding_system'. This structure keeps
various information about a specific code conversion (e.g. the
location of source and destination data).
Coding systems are classified into the following types by how to
represent a character in a byte sequence. Here's a brief descrition
about type.
o Emacs' internal format (emacs-utf-8)
The extended UTF-8 which allows eight-bit raw bytes mixed with
character codes. Emacs holds characters in buffers and strings by
this format.
Coding systems are classified into the following types depending on
the mechanism of encoding. Here's a brief descrition about type.
o UTF-8
@ -137,6 +129,13 @@ END-OF-LINE FORMAT
independent, any coding system described above can take any format
of end-of-line (except for no-conversion).
STRUCT CODING_SYSTEM
Before using a coding system for code conversion (i.e. decoding and
encoding), we setup a structure of type `struct coding_system'.
This structure keeps various information about a specific code
conversion (e.g. the location of source and destination data).
*/
/* COMMON MACROS */
@ -818,19 +817,27 @@ static int detected_mask[coding_category_raw_text] =
/* Like EMIT_ONE_BYTE, but emit two bytes; C1 and C2. */
#define EMIT_TWO_BYTES(c1, c2) \
do { \
produced_chars += 2; \
if (multibytep) \
{ \
CHAR_STRING_ADVANCE ((int) (c1), dst); \
CHAR_STRING_ADVANCE ((int) (c2), dst); \
} \
else \
{ \
*dst++ = (c1); \
*dst++ = (c2); \
} \
#define EMIT_TWO_BYTES(c1, c2) \
do { \
produced_chars += 2; \
if (multibytep) \
{ \
int ch; \
\
ch = (c1); \
if (ch >= 0x80) \
ch = BYTE8_TO_CHAR (ch); \
CHAR_STRING_ADVANCE (ch, dst); \
ch = (c2); \
if (ch >= 0x80) \
ch = BYTE8_TO_CHAR (ch); \
CHAR_STRING_ADVANCE (ch, dst); \
} \
else \
{ \
*dst++ = (c1); \
*dst++ = (c2); \
} \
} while (0)
@ -889,10 +896,14 @@ coding_set_source (coding)
coding->source = GAP_END_ADDR + coding->src_pos_byte;
else
{
if (coding->src_pos < GPT
&& coding->src_pos + coding->src_chars >= GPT)
move_gap_both (coding->src_pos, coding->src_pos_byte);
coding->source = BYTE_POS_ADDR (coding->src_pos_byte);
struct buffer *buf = XBUFFER (coding->src_object);
EMACS_INT beg_byte = BUF_BEG_BYTE (buf);
EMACS_INT gpt_byte = BUF_GPT_BYTE (buf);
unsigned char *beg_addr = BUF_BEG_ADDR (buf);
coding->source = beg_addr + coding->src_pos_byte - 1;
if (coding->src_pos_byte >= gpt_byte)
coding->source += BUF_GAP_SIZE (buf);
}
}
else if (STRINGP (coding->src_object))
@ -1182,7 +1193,7 @@ encode_coding_utf_8 (coding)
int *charbuf_end = charbuf + coding->charbuf_used;
unsigned char *dst = coding->destination + coding->produced;
unsigned char *dst_end = coding->destination + coding->dst_bytes;
int produced_chars;
int produced_chars = 0;
int c;
if (multibytep)
@ -1290,7 +1301,7 @@ decode_coding_utf_16 (coding)
src_base = src;
ONE_MORE_BYTE (c1);
ONE_MORE_BYTE (c2);
c = (c1 << 16) | c2;
c = (c1 << 8) | c2;
if (bom == utf_16_with_bom)
{
if (endian == utf_16_big_endian
@ -1333,7 +1344,7 @@ decode_coding_utf_16 (coding)
ONE_MORE_BYTE (c1);
ONE_MORE_BYTE (c2);
c = (endian == utf_16_big_endian
? ((c1 << 16) | c2) : ((c2 << 16) | c1));
? ((c1 << 8) | c2) : ((c2 << 8) | c1));
if (surrogate)
{
if (! UTF_16_LOW_SURROGATE_P (c))
@ -1404,8 +1415,8 @@ encode_coding_utf_16 (coding)
{
ASSURE_DESTINATION (safe_room);
c = *charbuf++;
if (c >= 0x110000)
c = 0xFFFF;
if (c >= MAX_UNICODE_CHAR)
c = coding->default_char;
if (c < 0x10000)
{
@ -4504,6 +4515,7 @@ setup_coding_system (coding_system, coding)
val = AREF (attrs, coding_attr_utf_16_endian);
CODING_UTF_16_ENDIAN (coding) = (NILP (val) ? utf_16_big_endian
: utf_16_little_endian);
CODING_UTF_16_SURROGATE (coding) = 0;
coding->detector = detect_coding_utf_16;
coding->decoder = decode_coding_utf_16;
coding->encoder = encode_coding_utf_16;
@ -5458,11 +5470,6 @@ decode_coding (coding)
coding->consumed = coding->src_bytes;
}
if (BUFFERP (coding->dst_object))
{
record_insert (coding->dst_pos, coding->produced_char);
}
return coding->result;
}