2 * LZO1X Decompressor from LZO
4 * Copyright (C) 1996-2012 Markus F.X.J. Oberhumer <markus@oberhumer.com>
6 * The full LZO package can be found at:
7 * http://www.oberhumer.com/opensource/lzo/
9 * Changed for Linux kernel use by:
10 * Nitin Gupta <nitingupta910@gmail.com>
11 * Richard Purdie <rpurdie@openedhand.com>
15 #include <linux/module.h>
16 #include <linux/kernel.h>
18 #include <asm/unaligned.h>
19 #include <linux/lzo.h>
22 #define HAVE_IP(t, x) \
23 (((size_t)(ip_end - ip) >= (size_t)(t + x)) && \
24 (((t + x) >= t) && ((t + x) >= x)))
26 #define HAVE_OP(t, x) \
27 (((size_t)(op_end - op) >= (size_t)(t + x)) && \
28 (((t + x) >= t) && ((t + x) >= x)))
30 #define NEED_IP(t, x) \
36 #define NEED_OP(t, x) \
39 goto output_overrun; \
42 #define TEST_LB(m_pos) \
45 goto lookbehind_overrun; \
48 int lzo1x_decompress_safe(const unsigned char *in, size_t in_len,
49 unsigned char *out, size_t *out_len)
52 const unsigned char *ip;
55 const unsigned char *m_pos;
56 const unsigned char * const ip_end = in + in_len;
57 unsigned char * const op_end = out + *out_len;
62 if (unlikely(in_len < 3))
70 goto copy_literal_run;
76 if (likely(state == 0)) {
77 if (unlikely(t == 0)) {
78 while (unlikely(*ip == 0)) {
87 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
88 if (likely(HAVE_IP(t, 15) && HAVE_OP(t, 15))) {
89 const unsigned char *ie = ip + t;
90 unsigned char *oe = op + t;
112 } else if (state != 4) {
125 m_pos = op - (1 + M2_MAX_OFFSET);
130 } else if (t >= 64) {
133 m_pos -= (t >> 2) & 7;
135 t = (t >> 5) - 1 + (3 - 1);
136 } else if (t >= 32) {
137 t = (t & 31) + (3 - 1);
138 if (unlikely(t == 2)) {
139 while (unlikely(*ip == 0)) {
148 next = get_unaligned_le16(ip);
154 m_pos -= (t & 8) << 11;
155 t = (t & 7) + (3 - 1);
156 if (unlikely(t == 2)) {
157 while (unlikely(*ip == 0)) {
165 next = get_unaligned_le16(ip);
174 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
175 if (op - m_pos >= 8) {
176 unsigned char *oe = op + t;
177 if (likely(HAVE_OP(t, 15))) {
203 unsigned char *oe = op + t;
216 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
217 if (likely(HAVE_IP(6, 0) && HAVE_OP(4, 0))) {
235 return (t != 3 ? LZO_E_ERROR :
236 ip == ip_end ? LZO_E_OK :
237 ip < ip_end ? LZO_E_INPUT_NOT_CONSUMED : LZO_E_INPUT_OVERRUN);
241 return LZO_E_INPUT_OVERRUN;
245 return LZO_E_OUTPUT_OVERRUN;
249 return LZO_E_LOOKBEHIND_OVERRUN;
252 EXPORT_SYMBOL_GPL(lzo1x_decompress_safe);
254 MODULE_LICENSE("GPL");
255 MODULE_DESCRIPTION("LZO1X Decompressor");