1
2
3#include <string.h>
4
5#include "util/compress.h"
6#include "util/debug.h"
7
8int zstd_init(struct zstd_data *data, int level)
9{
10 size_t ret;
11
12 data->dstream = ZSTD_createDStream();
13 if (data->dstream == NULL) {
14 pr_err("Couldn't create decompression stream.\n");
15 return -1;
16 }
17
18 ret = ZSTD_initDStream(data->dstream);
19 if (ZSTD_isError(ret)) {
20 pr_err("Failed to initialize decompression stream: %s\n", ZSTD_getErrorName(ret));
21 return -1;
22 }
23
24 if (!level)
25 return 0;
26
27 data->cstream = ZSTD_createCStream();
28 if (data->cstream == NULL) {
29 pr_err("Couldn't create compression stream.\n");
30 return -1;
31 }
32
33 ret = ZSTD_initCStream(data->cstream, level);
34 if (ZSTD_isError(ret)) {
35 pr_err("Failed to initialize compression stream: %s\n", ZSTD_getErrorName(ret));
36 return -1;
37 }
38
39 return 0;
40}
41
42int zstd_fini(struct zstd_data *data)
43{
44 if (data->dstream) {
45 ZSTD_freeDStream(data->dstream);
46 data->dstream = NULL;
47 }
48
49 if (data->cstream) {
50 ZSTD_freeCStream(data->cstream);
51 data->cstream = NULL;
52 }
53
54 return 0;
55}
56
57size_t zstd_compress_stream_to_records(struct zstd_data *data, void *dst, size_t dst_size,
58 void *src, size_t src_size, size_t max_record_size,
59 size_t process_header(void *record, size_t increment))
60{
61 size_t ret, size, compressed = 0;
62 ZSTD_inBuffer input = { src, src_size, 0 };
63 ZSTD_outBuffer output;
64 void *record;
65
66 while (input.pos < input.size) {
67 record = dst;
68 size = process_header(record, 0);
69 compressed += size;
70 dst += size;
71 dst_size -= size;
72 output = (ZSTD_outBuffer){ dst, (dst_size > max_record_size) ?
73 max_record_size : dst_size, 0 };
74 ret = ZSTD_compressStream(data->cstream, &output, &input);
75 ZSTD_flushStream(data->cstream, &output);
76 if (ZSTD_isError(ret)) {
77 pr_err("failed to compress %ld bytes: %s\n",
78 (long)src_size, ZSTD_getErrorName(ret));
79 memcpy(dst, src, src_size);
80 return src_size;
81 }
82 size = output.pos;
83 size = process_header(record, size);
84 compressed += size;
85 dst += size;
86 dst_size -= size;
87 }
88
89 return compressed;
90}
91
92size_t zstd_decompress_stream(struct zstd_data *data, void *src, size_t src_size,
93 void *dst, size_t dst_size)
94{
95 size_t ret;
96 ZSTD_inBuffer input = { src, src_size, 0 };
97 ZSTD_outBuffer output = { dst, dst_size, 0 };
98
99 while (input.pos < input.size) {
100 ret = ZSTD_decompressStream(data->dstream, &output, &input);
101 if (ZSTD_isError(ret)) {
102 pr_err("failed to decompress (B): %ld -> %ld, dst_size %ld : %s\n",
103 src_size, output.size, dst_size, ZSTD_getErrorName(ret));
104 break;
105 }
106 output.dst = dst + output.pos;
107 output.size = dst_size - output.pos;
108 }
109
110 return output.pos;
111}
112
