Go to most recent revision | Blame | Compare with Previous | Last modification | View Log | RSS feed
/*
Crown Copyright (c) 1997
This TenDRA(r) Computer Program is subject to Copyright
owned by the United Kingdom Secretary of State for Defence
acting through the Defence Evaluation and Research Agency
(DERA). It is made available to Recipients with a
royalty-free licence for its use, reproduction, transfer
to other parties and amendment for any purpose not excluding
product development provided that any such use et cetera
shall be deemed to be acceptance of the following conditions:-
(1) Its Recipients shall ensure that this Notice is
reproduced upon any copies or amended versions of it;
(2) Any amended version of it shall be clearly marked to
show both the nature of and the organisation responsible
for the relevant amendment or amendments;
(3) Its onward transfer from a recipient to another
party shall be deemed to be that party's acceptance of
these conditions;
(4) DERA gives no warranty or assurance as to its
quality or suitability for any purpose and DERA accepts
no liability whatsoever in relation to any use to which
it may be put.
*/
#include "config.h"
#include "types.h"
#include "ascii.h"
#include "file.h"
#include "pretty.h"
#include "tree.h"
#include "utility.h"
/*
MACRO DEFINITIONS
BUFFSIZE gives the size of the input buffer. HI_MASK and LO_MASK
are bit masks used to extract bits 8-15 and 0-7 respectively from
an integer.
*/
#define BUFFSIZE ( ( size_t ) 1024 )
#define HI_MASK ( ( unsigned ) 0xff00 )
#define LO_MASK ( ( unsigned ) 0x00ff )
/*
INPUT AND OUTPUT FILES AND BUFFERS
The input TDF capsule is read from tdf_file. The pretty-printed
output is placed into pp_file. The input uses the buffer
inbuffer.
*/
FILE *pp_file ;
static FILE *tdf_file ;
static char inbuffer [ BUFFSIZE ] ;
static int ib_ptr, ib_size ;
/*
POSITION IN INPUT FILE
The current position in the input file is recorded by means of a
place.
*/
place here ;
/*
INPUT AND OUTPUT VARIABLES
printflag is used to switch the printing on or off. The present
column number in the output file is given by column. The maximum
value attained by column is recorded in maximum. The last character
output is held in lastc. The flag read_error is used to indicate
that an error has occurred in reading the input file.
*/
int printflag = 1 ;
int column ;
int maximum ;
int lastc = 0 ;
int read_error = 0 ;
int dump = 0 ;
/*
OPEN FILES
The file name1 is opened for input and name2 for output. If name2
is the null string, the standard output is used.
*/
void open_files
PROTO_N ( ( name1, name2 ) )
PROTO_T ( char *name1 X char *name2 )
{
tdf_file = fopen ( name1, "rb" ) ;
if ( tdf_file == null ) fatal_error ( "Can't open %s", name1 ) ;
if ( name2 == null ) dflag = 0 ;
if ( dflag ) {
pp_file = fopen ( name2, "w" ) ;
if ( pp_file == null ) fatal_error ( "Can't open %s", name2 ) ;
} else {
pp_file = stdout ;
}
here.byte = 0 ;
here.bit = 0 ;
ib_size = 0 ;
return ;
}
/*
READ THE NEXT BYTE FROM THE INPUT FILE
This routine reads the next byte from the input file, putting it
into the worksp field of here.
*/
static void next_byte
PROTO_Z ()
{
if ( read_error ) {
here.worksp = 0xff ;
} else {
/* refill input buffer if required */
if ( ib_size == 0 ) {
ib_ptr = 0 ;
ib_size = ( int ) fread ( inbuffer, 1, BUFFSIZE, tdf_file ) ;
if ( ib_size == 0 ) {
/* if we have reached the end of the file... */
read_error = 1 ;
if ( !dump ) {
out ( "<reading error>" ) ;
input_error ( "Reading error" ) ;
}
}
}
/* get the next character */
if ( read_error ) {
here.worksp = 0xff ;
} else {
char c = inbuffer [ ib_ptr++ ] ;
here.worksp = ( unsigned ) ( c & 0xff ) ;
ib_size-- ;
}
}
return ;
}
/*
FETCH THE NEXT n BITS FROM THE INPUT FILE
This routine reads the next n bits from the input file and returns
them as an integer. n will rarely be as much as 8, so there is
no problem with overflow.
*/
long fetch
PROTO_N ( ( n ) )
PROTO_T ( int n )
{
int m ;
unsigned a = 0 ;
while ( n ) {
/* read the next byte if necessary */
if ( here.bit == 0 ) next_byte () ;
/* m = number of bits we need from this byte */
m = BYTESIZE - here.bit ;
if ( n < m ) m = n ;
/* extract m bytes from here.worksp */
here.worksp <<= m ;
a = ( a << m ) + ( ( here.worksp & HI_MASK ) >> BYTESIZE ) ;
here.worksp &= LO_MASK ;
n -= m ;
here.bit += m ;
if ( here.bit == BYTESIZE ) {
here.bit = 0 ;
here.byte++ ;
}
}
return ( ( long ) a ) ;
}
/*
ALIGN INPUT FILE TO AN 8 BIT BOUNDARY
Bits are read from the input file until it is on an 8 bit boundary.
*/
void byte_align
PROTO_Z ()
{
while ( !( here.bit == 0 || here.bit == BYTESIZE ) ) {
IGNORE fetch ( 1 ) ;
}
return ;
}
/*
GO TO A GIVEN PLACE IN THE INPUT FILE
The current position is set to the position indicated by the place p.
*/
void set_place
PROTO_N ( ( p ) )
PROTO_T ( place *p )
{
int s ;
here.byte = p->byte ;
here.bit = 0 ;
s = fseek ( tdf_file, here.byte, SEEK_SET ) ;
if ( s ) fatal_error ( "Internal file seek error" ) ;
ib_size = 0 ;
IGNORE fetch ( p->bit ) ;
return ;
}
/*
SKIP THE NEXT n BITS IN THE INPUT FILE
If n is small, the next n bits are read but discarded. Otherwise
set_place is used.
*/
void skip_bits
PROTO_N ( ( n ) )
PROTO_T ( long n )
{
if ( read_error ) return ;
if ( n <= 4 * BYTESIZE ) {
IGNORE fetch ( ( int ) n ) ;
} else {
place p ;
long b = posn ( here ) + n ;
p.byte = b / BYTESIZE ;
p.bit = ( int ) ( b % BYTESIZE ) ;
set_place ( &p ) ;
}
return ;
}
/*
ARRAY OF SPACES
The indentation spaces used during pretty-printing are stored in
an array.
*/
static char *spaces1 ;
/*
INITIALIZE SPACES
This routine initializes the array of indentation spaces, spaces1.
*/
void init_spaces
PROTO_N ( ( d ) )
PROTO_T ( int d )
{
int i, j ;
if ( helpflag ) {
spaces1 = alloc_nof ( char, 5000 ) ;
/* every dth character should be a '.' */
for ( i = 0, j = 0 ; i < 5000 ; i++ ) {
if ( ++j == d ) {
spaces1 [i] = '.' ;
j = 0 ;
} else {
spaces1 [i] = ' ' ;
}
}
}
return ;
}
/*
OUTPUT n SPACES
This routine outputs n indentation spaces, using the array spaces1
when appropriate.
*/
void spaces
PROTO_N ( ( n ) )
PROTO_T ( int n )
{
if ( n < 0 ) n = 0 ;
if ( printflag ) {
if ( helpflag ) {
if ( n ) {
IGNORE fwrite ( spaces1, sizeof ( char ),
( size_t ) n, pp_file ) ;
}
} else {
int i ;
int q = ( n / TBSIZE ) ;
int r = ( n % TBSIZE ) ;
for ( i = 0 ; i < q ; i++ ) IGNORE fputc ( TAB, pp_file ) ;
for ( i = 0 ; i < r ; i++ ) IGNORE fputc ( SPACE, pp_file ) ;
}
}
column = n ;
lastc = ' ' ;
return ;
}