1/*
2 * Copyright (C) 2015 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#ifndef __FEC_H__
18#define __FEC_H__
19
20#include <utils/Compat.h>
21#include <string>
22#include <vector>
23#include <fec/io.h>
24#include <fec/ecc.h>
25
26#define IMAGE_MIN_THREADS     1
27#define IMAGE_MAX_THREADS     128
28
29#define INFO(x...) \
30    fprintf(stderr, x);
31#define FATAL(x...) { \
32    fprintf(stderr, x); \
33    exit(1); \
34}
35
36#define unlikely(x)    __builtin_expect(!!(x), 0)
37
38struct image {
39    /* if true, decode file in place instead of creating a new output file */
40    bool inplace;
41    /* if true, use memory mapping instead of copying all input into memory */
42    bool mmap;
43    /* if true, assume input is a sparse file */
44    bool sparse;
45    /* if true, print more verbose information to stderr */
46    bool verbose;
47    const char *fec_filename;
48    int fec_fd;
49    int inp_fd;
50    /* the number of Reed-Solomon generator polynomial roots, also the number
51       of parity bytes generated for each N bytes in RS(M, N) */
52    int roots;
53    /* for RS(M, N), N = M - roots */
54    int rs_n;
55    int threads;
56    uint32_t fec_size;
57    uint64_t blocks;
58    uint64_t inp_size;
59    uint64_t pos;
60    uint64_t rounds;
61    uint64_t rv;
62    uint8_t *fec;
63    uint8_t *fec_mmap_addr;
64    uint8_t *input;
65    uint8_t *output;
66};
67
68struct image_proc_ctx;
69typedef void (*image_proc_func)(image_proc_ctx *);
70
71struct image_proc_ctx {
72    image_proc_func func;
73    int id;
74    image *ctx;
75    uint64_t rv;
76    uint64_t fec_pos;
77    uint64_t start;
78    uint64_t end;
79    void *rs;
80};
81
82extern bool image_load(const std::vector<std::string>& filename, image *ctx,
83        bool output_needed);
84extern bool image_save(const std::string& filename, image *ctx);
85
86extern bool image_ecc_new(const std::string& filename, image *ctx);
87extern bool image_ecc_load(const std::string& filename, image *ctx);
88extern bool image_ecc_save(image *ctx);
89
90extern bool image_process(image_proc_func f, image *ctx);
91
92extern void image_init(image *ctx);
93extern void image_free(image *ctx);
94
95inline uint8_t image_get_interleaved_byte(uint64_t i, image *ctx)
96{
97    uint64_t offset = fec_ecc_interleave(i, ctx->rs_n, ctx->rounds);
98
99    if (unlikely(offset >= ctx->inp_size)) {
100        return 0;
101    }
102
103    return ctx->input[offset];
104}
105
106inline void image_set_interleaved_byte(uint64_t i, image *ctx,
107        uint8_t value)
108{
109    uint64_t offset = fec_ecc_interleave(i, ctx->rs_n, ctx->rounds);
110
111    if (unlikely(offset >= ctx->inp_size)) {
112        assert(value == 0);
113    } else if (ctx->output && ctx->output[offset] != value) {
114        ctx->output[offset] = value;
115    }
116}
117
118#endif // __FEC_H__
119