1 /* LZ4file API example : compress a file
2 * Modified from an example code by anjiahao
3 *
4 * This example will demonstrate how
5 * to manipulate lz4 compressed files like
6 * normal files */
7
8 #include <assert.h>
9 #include <stdio.h>
10 #include <stdlib.h>
11 #include <string.h>
12 #include <sys/stat.h>
13
14 #include <lz4file.h>
15
16
17 #define CHUNK_SIZE (16*1024)
18
get_file_size(char * filename)19 static size_t get_file_size(char *filename)
20 {
21 struct stat statbuf;
22
23 if (filename == NULL) {
24 return 0;
25 }
26
27 if(stat(filename,&statbuf)) {
28 return 0;
29 }
30
31 return statbuf.st_size;
32 }
33
compress_file(FILE * f_in,FILE * f_out)34 static int compress_file(FILE* f_in, FILE* f_out)
35 {
36 assert(f_in != NULL); assert(f_out != NULL);
37
38 LZ4F_errorCode_t ret = LZ4F_OK_NoError;
39 size_t len;
40 LZ4_writeFile_t* lz4fWrite;
41 void* const buf = malloc(CHUNK_SIZE);
42 if (!buf) {
43 printf("error: memory allocation failed \n");
44 }
45
46 /* Of course, you can also use prefsPtr to
47 * set the parameters of the compressed file
48 * NULL is use default
49 */
50 ret = LZ4F_writeOpen(&lz4fWrite, f_out, NULL);
51 if (LZ4F_isError(ret)) {
52 printf("LZ4F_writeOpen error: %s\n", LZ4F_getErrorName(ret));
53 free(buf);
54 return 1;
55 }
56
57 while (1) {
58 len = fread(buf, 1, CHUNK_SIZE, f_in);
59
60 if (ferror(f_in)) {
61 printf("fread error\n");
62 goto out;
63 }
64
65 /* nothing to read */
66 if (len == 0) {
67 break;
68 }
69
70 ret = LZ4F_write(lz4fWrite, buf, len);
71 if (LZ4F_isError(ret)) {
72 printf("LZ4F_write: %s\n", LZ4F_getErrorName(ret));
73 goto out;
74 }
75 }
76
77 out:
78 free(buf);
79 if (LZ4F_isError(LZ4F_writeClose(lz4fWrite))) {
80 printf("LZ4F_writeClose: %s\n", LZ4F_getErrorName(ret));
81 return 1;
82 }
83
84 return 0;
85 }
86
decompress_file(FILE * f_in,FILE * f_out)87 static int decompress_file(FILE* f_in, FILE* f_out)
88 {
89 assert(f_in != NULL); assert(f_out != NULL);
90
91 LZ4F_errorCode_t ret = LZ4F_OK_NoError;
92 LZ4_readFile_t* lz4fRead;
93 void* const buf= malloc(CHUNK_SIZE);
94 if (!buf) {
95 printf("error: memory allocation failed \n");
96 }
97
98 ret = LZ4F_readOpen(&lz4fRead, f_in);
99 if (LZ4F_isError(ret)) {
100 printf("LZ4F_readOpen error: %s\n", LZ4F_getErrorName(ret));
101 free(buf);
102 return 1;
103 }
104
105 while (1) {
106 ret = LZ4F_read(lz4fRead, buf, CHUNK_SIZE);
107 if (LZ4F_isError(ret)) {
108 printf("LZ4F_read error: %s\n", LZ4F_getErrorName(ret));
109 goto out;
110 }
111
112 /* nothing to read */
113 if (ret == 0) {
114 break;
115 }
116
117 if(fwrite(buf, 1, ret, f_out) != ret) {
118 printf("write error!\n");
119 goto out;
120 }
121 }
122
123 out:
124 free(buf);
125 if (LZ4F_isError(LZ4F_readClose(lz4fRead))) {
126 printf("LZ4F_readClose: %s\n", LZ4F_getErrorName(ret));
127 return 1;
128 }
129
130 if (ret) {
131 return 1;
132 }
133
134 return 0;
135 }
136
compareFiles(FILE * fp0,FILE * fp1)137 int compareFiles(FILE* fp0, FILE* fp1)
138 {
139 int result = 0;
140
141 while (result==0) {
142 char b0[1024];
143 char b1[1024];
144 size_t const r0 = fread(b0, 1, sizeof(b0), fp0);
145 size_t const r1 = fread(b1, 1, sizeof(b1), fp1);
146
147 result = (r0 != r1);
148 if (!r0 || !r1) break;
149 if (!result) result = memcmp(b0, b1, r0);
150 }
151
152 return result;
153 }
154
main(int argc,const char ** argv)155 int main(int argc, const char **argv) {
156 char inpFilename[256] = { 0 };
157 char lz4Filename[256] = { 0 };
158 char decFilename[256] = { 0 };
159
160 if (argc < 2) {
161 printf("Please specify input filename\n");
162 return 0;
163 }
164
165 snprintf(inpFilename, 256, "%s", argv[1]);
166 snprintf(lz4Filename, 256, "%s.lz4", argv[1]);
167 snprintf(decFilename, 256, "%s.lz4.dec", argv[1]);
168
169 printf("inp = [%s]\n", inpFilename);
170 printf("lz4 = [%s]\n", lz4Filename);
171 printf("dec = [%s]\n", decFilename);
172
173 /* compress */
174 { FILE* const inpFp = fopen(inpFilename, "rb");
175 FILE* const outFp = fopen(lz4Filename, "wb");
176 printf("compress : %s -> %s\n", inpFilename, lz4Filename);
177 LZ4F_errorCode_t ret = compress_file(inpFp, outFp);
178 fclose(inpFp);
179 fclose(outFp);
180
181 if (ret) {
182 printf("compression error: %s\n", LZ4F_getErrorName(ret));
183 return 1;
184 }
185
186 printf("%s: %zu → %zu bytes, %.1f%%\n",
187 inpFilename,
188 get_file_size(inpFilename),
189 get_file_size(lz4Filename), /* might overflow is size_t is 32 bits and size_{in,out} > 4 GB */
190 (double)get_file_size(lz4Filename) / get_file_size(inpFilename) * 100);
191
192 printf("compress : done\n");
193 }
194
195 /* decompress */
196 {
197 FILE* const inpFp = fopen(lz4Filename, "rb");
198 FILE* const outFp = fopen(decFilename, "wb");
199
200 printf("decompress : %s -> %s\n", lz4Filename, decFilename);
201 LZ4F_errorCode_t ret = decompress_file(inpFp, outFp);
202
203 fclose(outFp);
204 fclose(inpFp);
205
206 if (ret) {
207 printf("compression error: %s\n", LZ4F_getErrorName(ret));
208 return 1;
209 }
210
211 printf("decompress : done\n");
212 }
213
214 /* verify */
215 { FILE* const inpFp = fopen(inpFilename, "rb");
216 FILE* const decFp = fopen(decFilename, "rb");
217
218 printf("verify : %s <-> %s\n", inpFilename, decFilename);
219 int const cmp = compareFiles(inpFp, decFp);
220
221 fclose(decFp);
222 fclose(inpFp);
223
224 if (cmp) {
225 printf("corruption detected : decompressed file differs from original\n");
226 return cmp;
227 }
228
229 printf("verify : OK\n");
230 }
231
232 }
233