The Annoyance Filter.pdf - Fourmilab

§108 ANNOYANCE-FILTER FLASH STREAM DECODER 87
108. 16 and 32 bit quantities are stored in little-endian byte order. These methods, declared within
the class so they’re inlined in the interest of efficiency, use the get8 primitive byte input method to
assemble the wider quantities. The get16n and get32n methods read a series of n consecutive values of
the corresponding type into an array.
〈 Read 16 and 32 bit quantities from Flash file 108 〉 ≡
unsigned short get16 (void)
{
unsigned short u16 ;
}
u16 = get8 ( );
u16 |= get8 ( ) ≪ 8;
return u16 ;
unsigned int get32 (void)
{
unsigned int u32 ;
}
u32 = get8 ( );
u32 |= get8 ( ) ≪ 8;
u32 |= get8 ( ) ≪ 16;
u32 |= get8 ( ) ≪ 24;
return u32 ;
void get16n (unsigned short ∗buf , const int n)
{
for (int i = 0; (¬eof ) ∧ (i < n); i++) {
buf [i] = get16 ( );
}
}
void get32n (unsigned int ∗buf , const int n)
{
for (int i = 0; (¬eof ) ∧ (i < n); i++) {
buf [i] = get32 ( );
}
}
This code is used in section 100.