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 return 1;
45 }
46
47 /* Of course, you can also use prefsPtr to
48 * set the parameters of the compressed file
49 * NULL is use default
50 */
51 ret = LZ4F_writeOpen(&lz4fWrite, f_out, NULL);
52 if (LZ4F_isError(ret)) {
53 printf("LZ4F_writeOpen error: %s\n", LZ4F_getErrorName(ret));
54 free(buf);
55 return 1;
56 }
57
58 while (1) {
59 len = fread(buf, 1, CHUNK_SIZE, f_in);
60
61 if (ferror(f_in)) {
62 printf("fread error\n");
63 goto out;
64 }
65
66 /* nothing to read */
67 if (len == 0) {
68 break;
69 }
70
71 ret = LZ4F_write(lz4fWrite, buf, len);
72 if (LZ4F_isError(ret)) {
73 printf("LZ4F_write: %s\n", LZ4F_getErrorName(ret));
74 goto out;
75 }
76 }
77
78 out:
79 free(buf);
80 if (LZ4F_isError(LZ4F_writeClose(lz4fWrite))) {
81 printf("LZ4F_writeClose: %s\n", LZ4F_getErrorName(ret));
82 return 1;
83 }
84
85 return 0;
86 }
87
decompress_file(FILE * f_in,FILE * f_out)88 static int decompress_file(FILE* f_in, FILE* f_out)
89 {
90 assert(f_in != NULL); assert(f_out != NULL);
91
92 LZ4F_errorCode_t ret = LZ4F_OK_NoError;
93 LZ4_readFile_t* lz4fRead;
94 void* const buf= malloc(CHUNK_SIZE);
95 if (!buf) {
96 printf("error: memory allocation failed \n");
97 }
98
99 ret = LZ4F_readOpen(&lz4fRead, f_in);
100 if (LZ4F_isError(ret)) {
101 printf("LZ4F_readOpen error: %s\n", LZ4F_getErrorName(ret));
102 free(buf);
103 return 1;
104 }
105
106 while (1) {
107 ret = LZ4F_read(lz4fRead, buf, CHUNK_SIZE);
108 if (LZ4F_isError(ret)) {
109 printf("LZ4F_read error: %s\n", LZ4F_getErrorName(ret));
110 goto out;
111 }
112
113 /* nothing to read */
114 if (ret == 0) {
115 break;
116 }
117
118 if(fwrite(buf, 1, ret, f_out) != ret) {
119 printf("write error!\n");
120 goto out;
121 }
122 }
123
124 out:
125 free(buf);
126 if (LZ4F_isError(LZ4F_readClose(lz4fRead))) {
127 printf("LZ4F_readClose: %s\n", LZ4F_getErrorName(ret));
128 return 1;
129 }
130
131 if (ret) {
132 return 1;
133 }
134
135 return 0;
136 }
137
compareFiles(FILE * fp0,FILE * fp1)138 int compareFiles(FILE* fp0, FILE* fp1)
139 {
140 int result = 0;
141
142 while (result==0) {
143 char b0[1024];
144 char b1[1024];
145 size_t const r0 = fread(b0, 1, sizeof(b0), fp0);
146 size_t const r1 = fread(b1, 1, sizeof(b1), fp1);
147
148 result = (r0 != r1);
149 if (!r0 || !r1) break;
150 if (!result) result = memcmp(b0, b1, r0);
151 }
152
153 return result;
154 }
155
main(int argc,const char ** argv)156 int main(int argc, const char **argv) {
157 char inpFilename[256] = { 0 };
158 char lz4Filename[256] = { 0 };
159 char decFilename[256] = { 0 };
160
161 if (argc < 2) {
162 printf("Please specify input filename\n");
163 return 0;
164 }
165
166 snprintf(inpFilename, 256, "%s", argv[1]);
167 snprintf(lz4Filename, 256, "%s.lz4", argv[1]);
168 snprintf(decFilename, 256, "%s.lz4.dec", argv[1]);
169
170 printf("inp = [%s]\n", inpFilename);
171 printf("lz4 = [%s]\n", lz4Filename);
172 printf("dec = [%s]\n", decFilename);
173
174 /* compress */
175 { FILE* const inpFp = fopen(inpFilename, "rb");
176 FILE* const outFp = fopen(lz4Filename, "wb");
177 printf("compress : %s -> %s\n", inpFilename, lz4Filename);
178 LZ4F_errorCode_t ret = compress_file(inpFp, outFp);
179 fclose(inpFp);
180 fclose(outFp);
181
182 if (ret) {
183 printf("compression error: %s\n", LZ4F_getErrorName(ret));
184 return 1;
185 }
186
187 printf("%s: %zu → %zu bytes, %.1f%%\n",
188 inpFilename,
189 get_file_size(inpFilename),
190 get_file_size(lz4Filename), /* might overflow is size_t is 32 bits and size_{in,out} > 4 GB */
191 (double)get_file_size(lz4Filename) / get_file_size(inpFilename) * 100);
192
193 printf("compress : done\n");
194 }
195
196 /* decompress */
197 {
198 FILE* const inpFp = fopen(lz4Filename, "rb");
199 FILE* const outFp = fopen(decFilename, "wb");
200
201 printf("decompress : %s -> %s\n", lz4Filename, decFilename);
202 LZ4F_errorCode_t ret = decompress_file(inpFp, outFp);
203
204 fclose(outFp);
205 fclose(inpFp);
206
207 if (ret) {
208 printf("compression error: %s\n", LZ4F_getErrorName(ret));
209 return 1;
210 }
211
212 printf("decompress : done\n");
213 }
214
215 /* verify */
216 { FILE* const inpFp = fopen(inpFilename, "rb");
217 FILE* const decFp = fopen(decFilename, "rb");
218
219 printf("verify : %s <-> %s\n", inpFilename, decFilename);
220 int const cmp = compareFiles(inpFp, decFp);
221
222 fclose(decFp);
223 fclose(inpFp);
224
225 if (cmp) {
226 printf("corruption detected : decompressed file differs from original\n");
227 return cmp;
228 }
229
230 printf("verify : OK\n");
231 }
232
233 }
234