1 #include <libpayload.h>
3 // This GETBIT is supposed to work on little endian
4 // 32bit systems. The algorithm will definitely need
5 // some fixing on other systems, but it might not be
6 // a problem since the nrv2b binary behaves the same..
15 #define GETBIT_8(bb, src, ilen) \
16 (((bb = bb & 0x7f ? bb*2 : ((unsigned)src[ilen++]*2+1)) >> 8) & 1)
18 #define GETBIT_LE16(bb, src, ilen) \
19 (bb*=2,bb&0xffff ? (bb>>16)&1 : (ilen+=2,((bb=(src[ilen-2]+src[ilen-1]*256u)*2+1)>>16)&1))
20 #define GETBIT_LE32(bb, src, ilen) \
21 (bc > 0 ? ((bb>>--bc)&1) : (bc=31,\
22 bb=*(const u32 *)((src)+ilen),ilen+=4,(bb>>31)&1))
24 #if ENDIAN == 0 && BITSIZE == 8
25 #define GETBIT(bb, src, ilen) GETBIT_8(bb, src, ilen)
27 #if ENDIAN == 0 && BITSIZE == 16
28 #define GETBIT(bb, src, ilen) GETBIT_LE16(bb, src, ilen)
30 #if ENDIAN == 0 && BITSIZE == 32
31 #define GETBIT(bb, src, ilen) GETBIT_LE32(bb, src, ilen)
34 unsigned long unrv2b(u8 *src, u8 *dst, unsigned long *ilen_p)
36 unsigned long ilen = 0, olen = 0, last_m_off = 1;
43 /* FIXME: check olen with the length stored in first 4 bytes */
46 unsigned int m_off, m_len;
47 while (GETBIT(bb, src, ilen)) {
48 dst[olen++] = src[ilen++];
53 m_off = m_off * 2 + GETBIT(bb, src, ilen);
54 } while (!GETBIT(bb, src, ilen));
58 m_off = (m_off - 3) * 256 + src[ilen++];
59 if (m_off == 0xffffffffU)
64 m_len = GETBIT(bb, src, ilen);
65 m_len = m_len * 2 + GETBIT(bb, src, ilen);
69 m_len = m_len * 2 + GETBIT(bb, src, ilen);
70 } while (!GETBIT(bb, src, ilen));
73 m_len += (m_off > 0xd00);
75 m_pos = dst + olen - m_off;
76 dst[olen++] = *m_pos++;
78 dst[olen++] = *m_pos++;
79 } while (--m_len > 0);