怎样封装zlib中的压缩解压缩函数

ddbo

在vc6中，我现在要做一个静态库来封装zlib中的compresst和uncompress函数
我是个新手请大家指教，
最好能给我一份源代码
谢谢

sunlan

zlib有示例代码的

ddbo

我知道有示例代码
我看不明白
哪位大哥能帮我封装一下compresst和uncompress

sunlan

1. 
   
2. /* zpipe.c: example of proper use of zlib's inflate() and deflate()
   
3.    Not copyrighted -- provided to the public domain
   
4.    Version 1.2  9 November 2004  Mark Adler */
   
5. 
   
6. /* Version history:
   
7.    1.0  30 Oct 2004  First version
   
8.    1.1   8 Nov 2004  Add void casting for unused return values
   
9.                      Use switch statement for inflate() return values
   
10.    1.2   9 Nov 2004  Add assertions to document zlib guarantees
    
11. */
    
12. 
    
13. #include <stdio.h>
    
14. #include <string.h>
    
15. #include <assert.h>
    
16. #include "zlib.h"
    
17. 
    
18. #define CHUNK 16384
    
19. 
    
20. /* Compress from file source to file dest until EOF on source.
    
21.    def() returns Z_OK on success, Z_MEM_ERROR if memory could not be
    
22.    allocated for processing, Z_STREAM_ERROR if an invalid compression
    
23.    level is supplied, Z_VERSION_ERROR if the version of zlib.h and the
    
24.    version of the library linked do not match, or Z_ERRNO if there is
    
25.    an error reading or writing the files. */
    
26. int def(FILE *source, FILE *dest, int level)
    
27. {
    
28.     int ret, flush;
    
29.     unsigned have;
    
30.     z_stream strm;
    
31.     char in[CHUNK];
    
32.     char out[CHUNK];
    
33. 
    
34.     /* allocate deflate state */
    
35.     strm.zalloc = Z_NULL;
    
36.     strm.zfree = Z_NULL;
    
37.     strm.opaque = Z_NULL;
    
38.     ret = deflateInit(&strm, level);
    
39.     if (ret != Z_OK)
    
40.         return ret;
    
41. 
    
42.     /* compress until end of file */
    
43.     do {
    
44.         strm.avail_in = fread(in, 1, CHUNK, source);
    
45.         if (ferror(source)) {
    
46.             (void)deflateEnd(&strm);
    
47.             return Z_ERRNO;
    
48.         }
    
49.         flush = feof(source) ? Z_FINISH : Z_NO_FLUSH;
    
50.         strm.next_in = in;
    
51. 
    
52.         /* run deflate() on input until output buffer not full, finish
    
53.            compression if all of source has been read in */
    
54.         do {
    
55.             strm.avail_out = CHUNK;
    
56.             strm.next_out = out;
    
57.             ret = deflate(&strm, flush);    /* no bad return value */
    
58.             assert(ret != Z_STREAM_ERROR);  /* state not clobbered */
    
59.             have = CHUNK - strm.avail_out;
    
60.             if (fwrite(out, 1, have, dest) != have || ferror(dest)) {
    
61.                 (void)deflateEnd(&strm);
    
62.                 return Z_ERRNO;
    
63.             }
    
64.         } while (strm.avail_out == 0);
    
65.         assert(strm.avail_in == 0);     /* all input will be used */
    
66. 
    
67.         /* done when last data in file processed */
    
68.     } while (flush != Z_FINISH);
    
69.     assert(ret == Z_STREAM_END);        /* stream will be complete */
    
70. 
    
71.     /* clean up and return */
    
72.     (void)deflateEnd(&strm);
    
73.     return Z_OK;
    
74. }
    
75. 
    
76. /* Decompress from file source to file dest until stream ends or EOF.
    
77.    inf() returns Z_OK on success, Z_MEM_ERROR if memory could not be
    
78.    allocated for processing, Z_DATA_ERROR if the deflate data is
    
79.    invalid or incomplete, Z_VERSION_ERROR if the version of zlib.h and
    
80.    the version of the library linked do not match, or Z_ERRNO if there
    
81.    is an error reading or writing the files. */
    
82. int inf(FILE *source, FILE *dest)
    
83. {
    
84.     int ret;
    
85.     unsigned have;
    
86.     z_stream strm;
    
87.     char in[CHUNK];
    
88.     char out[CHUNK];
    
89. 
    
90.     /* allocate inflate state */
    
91.     strm.zalloc = Z_NULL;
    
92.     strm.zfree = Z_NULL;
    
93.     strm.opaque = Z_NULL;
    
94.     strm.avail_in = 0;
    
95.     strm.next_in = Z_NULL;
    
96.     ret = inflateInit(&strm);
    
97.     if (ret != Z_OK)
    
98.         return ret;
    
99. 
    
100.     /* decompress until deflate stream ends or end of file */
     
101.     do {
     
102.         strm.avail_in = fread(in, 1, CHUNK, source);
     
103.         if (ferror(source)) {
     
104.             (void)inflateEnd(&strm);
     
105.             return Z_ERRNO;
     
106.         }
     
107.         if (strm.avail_in == 0)
     
108.             break;
     
109.         strm.next_in = in;
     
110. 
     
111.         /* run inflate() on input until output buffer not full */
     
112.         do {
     
113.             strm.avail_out = CHUNK;
     
114.             strm.next_out = out;
     
115.             ret = inflate(&strm, Z_NO_FLUSH);
     
116.             assert(ret != Z_STREAM_ERROR);  /* state not clobbered */
     
117.             switch (ret) {
     
118.             case Z_NEED_DICT:
     
119.                 ret = Z_DATA_ERROR;     /* and fall through */
     
120.             case Z_DATA_ERROR:
     
121.             case Z_MEM_ERROR:
     
122.                 (void)inflateEnd(&strm);
     
123.                 return ret;
     
124.             }
     
125.             have = CHUNK - strm.avail_out;
     
126.             if (fwrite(out, 1, have, dest) != have || ferror(dest)) {
     
127.                 (void)inflateEnd(&strm);
     
128.                 return Z_ERRNO;
     
129.             }
     
130.         } while (strm.avail_out == 0);
     
131.         assert(strm.avail_in == 0);     /* all input will be used */
     
132. 
     
133.         /* done when inflate() says it's done */
     
134.     } while (ret != Z_STREAM_END);
     
135. 
     
136.     /* clean up and return */
     
137.     (void)inflateEnd(&strm);
     
138.     return ret == Z_STREAM_END ? Z_OK : Z_DATA_ERROR;
     
139. }
     
140. 
     
141. /* report a zlib or i/o error */
     
142. void zerr(int ret)
     
143. {
     
144.     fputs("zpipe: ", stderr);
     
145.     switch (ret) {
     
146.     case Z_ERRNO:
     
147.         if (ferror(stdin))
     
148.             fputs("error reading stdin\n", stderr);
     
149.         if (ferror(stdout))
     
150.             fputs("error writing stdout\n", stderr);
     
151.         break;
     
152.     case Z_STREAM_ERROR:
     
153.         fputs("invalid compression level\n", stderr);
     
154.         break;
     
155.     case Z_DATA_ERROR:
     
156.         fputs("invalid or incomplete deflate data\n", stderr);
     
157.         break;
     
158.     case Z_MEM_ERROR:
     
159.         fputs("out of memory\n", stderr);
     
160.         break;
     
161.     case Z_VERSION_ERROR:
     
162.         fputs("zlib version mismatch!\n", stderr);
     
163.     }
     
164. }
     
165. 
     
166. /* compress or decompress from stdin to stdout */
     
167. int main(int argc, char **argv)
     
168. {
     
169.     int ret;
     
170. 
     
171.     /* do compression if no arguments */
     
172.     if (argc == 1) {
     
173.         ret = def(stdin, stdout, Z_DEFAULT_COMPRESSION);
     
174.         if (ret != Z_OK)
     
175.             zerr(ret);
     
176.         return ret;
     
177.     }
     
178. 
     
179.     /* do decompression if -d specified */
     
180.     else if (argc == 2 && strcmp(argv[1], "-d") == 0) {
     
181.         ret = inf(stdin, stdout);
     
182.         if (ret != Z_OK)
     
183.             zerr(ret);
     
184.         return ret;
     
185.     }
     
186. 
     
187.     /* otherwise, report usage */
     
188.     else {
     
189.         fputs("zpipe usage: zpipe [-d] < source > dest\n", stderr);
     
190.         return 1;
     
191.     }
     
192. }
     

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DraculaW

-_-!

伸手党

pilgrim_kevin

原帖由 ddbo 于 2008-8-1 11:39 发表
我知道有示例代码
我看不明白
哪位大哥能帮我封装一下compresst和uncompress

自己动手，丰衣足食。

mo_yuan_ming

原帖由 ddbo 于 2008-8-1 11:39 发表
我知道有示例代码
我看不明白
哪位大哥能帮我封装一下compresst和uncompress

看不懂算法实现 接口应该可以看懂吧 接口看懂不就可以封装了吗？