factor/library/io/buffer.factor

106 lines
3.3 KiB
Factor

! Copyright (C) 2004, 2005 Mackenzie Straight.
! See http://factor.sf.net/license.txt for BSD license.
IN: io-internals
USING: alien errors kernel kernel-internals math strings ;
TUPLE: buffer size ptr fill pos ;
: imalloc ( size -- address )
"int" "libc" "malloc" [ "ulong" ] alien-invoke ;
: ifree ( address -- )
"void" "libc" "free" [ "ulong" ] alien-invoke ;
: irealloc ( address size -- address )
"int" "libc" "realloc" [ "ulong" "ulong" ] alien-invoke ;
: imemcpy ( dst src size -- )
"void" "libc" "memcpy" [ "ulong" "ulong" "ulong" ] alien-invoke ;
C: buffer ( size -- buffer )
2dup set-buffer-size
swap imalloc swap [ set-buffer-ptr ] keep
0 swap [ set-buffer-fill ] keep
0 swap [ set-buffer-pos ] keep ;
: buffer-free ( buffer -- )
#! Frees the C memory associated with the buffer.
dup buffer-ptr ifree 0 swap set-buffer-ptr ;
: buffer-contents ( buffer -- string )
#! Returns the current contents of the buffer.
dup buffer-ptr over buffer-pos +
over buffer-fill rot buffer-pos - memory>string ;
: buffer-reset ( count buffer -- )
#! Reset the position to 0 and the fill pointer to count.
[ set-buffer-fill ] keep 0 swap set-buffer-pos ;
: buffer-consume ( count buffer -- )
#! Consume count characters from the beginning of the buffer.
[ buffer-pos + ] keep
[ buffer-fill min ] keep
[ set-buffer-pos ] keep
dup buffer-pos over buffer-fill = [
[ 0 swap set-buffer-pos ] keep
[ 0 swap set-buffer-fill ] keep
] when drop ;
: buffer@ ( buffer -- int ) dup buffer-ptr swap buffer-pos + ;
: buffer-first-n ( count buffer -- string )
[ dup buffer-fill swap buffer-pos - min ] keep
buffer@ swap memory>string ;
: buffer> ( count buffer -- string )
[ buffer-first-n ] 2keep buffer-consume ;
: buffer>> ( buffer -- string )
[ buffer-contents ] keep 0 swap buffer-reset ;
: buffer-length ( buffer -- length )
#! Returns the amount of unconsumed input in the buffer.
dup buffer-fill swap buffer-pos - ;
: buffer-capacity ( buffer -- int )
#! Returns the amount of data that may be added to the buffer.
dup buffer-size swap buffer-fill - ;
: check-overflow ( string buffer -- )
buffer-capacity swap string-length < [
"Buffer overflow" throw
] when ;
: >buffer ( string buffer -- )
2dup check-overflow
[ dup buffer-ptr swap buffer-fill + string>memory ] 2keep
[ buffer-fill swap string-length + ] keep set-buffer-fill ;
: buffer-extend ( length buffer -- )
#! Increases the size of the buffer by length.
[ buffer-size + dup ] keep [ buffer-ptr swap ] keep
>r irealloc r>
[ set-buffer-ptr ] keep set-buffer-size ;
: n>buffer ( count buffer -- )
#! Increases the fill pointer by count.
[ buffer-fill + ] keep set-buffer-fill ;
: buffer-end ( buffer -- int ) dup buffer-ptr swap buffer-fill + ;
: buffer-pop ( buffer -- char )
[ buffer@ <alien> 0 alien-unsigned-1 1 ] keep
buffer-consume ;
: buffer-append ( buffer buffer -- )
#! Append first buffer to second buffer.
2dup buffer-end over buffer-ptr rot buffer-fill imemcpy
>r buffer-fill r> n>buffer ;
: buffer-set ( string buffer -- )
2dup buffer-ptr string>memory
>r string-length r> buffer-reset ;
: string>buffer ( string - -buffer )
dup string-length <buffer> tuck buffer-set ;