用zlib压缩解压缩，请各位看看程序有什么问题

[asdk77]

关于zlib压缩解压缩问题，请各位看看程序哪有问题？

1）createfile.c 将3句话压缩存入file.txt文档中
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "zlib.h"

unsigned char* compression(const char* s)
{
unsigned char *buf;

unsigned long slen = strlen(s) +1;

unsigned long buflen = compressBound(slen);

buf = (unsigned char*)malloc(sizeof(unsigned char)*buflen);

compress(buf, &buflen, (const Bytef *)s, slen);

return buf;



}



void main()

{

FILE *pf;

char *p1 = "this document is distributed in the hope that it will be useful, but without any warranty;";

char *p2 = "without even the implied warranty of merchantability or fittness for a particular purpose;";

char *p3 = "you should have received a copy of the GNU General Public License along with this document;";

pf = fopen("file.txt", "wr");


unsigned char* temp;

temp = compression(p1);

fprintf(pf, "%s\n", temp);

free(temp); //相当用free了compression函数中的buf?

temp = compression(p2);

fprintf(pf, "%s\n", temp);

free(temp);

temp = compression(p3);

fprintf(pf, "%s\n", temp);

free(temp);

}


2) 从file.txt文档中读取压缩字符串进行解压缩，将解压后的字符串存入newfile.txt中


#include<stdio.h>

#include<stdlib.h>

#include<string.h>

#include"zlib.h"


#define LINE 1024


unsigned char *decompression(char* s)

{

unsigned char *dest；

unsigned long len = strlen(s) + 1;

unsigned long destlen = (len<<1)*2;

dest = (unsigned char*)malloc(sizeof(unsigned char)*destlen);

uncompress(dest, &destlen, s, len);

return dest;

}

void main()

{


FILE *pf = fopen("file.txt", "r");

FILE *nf = fopen("newfile.txt", "wr");

unsigned char *buf = (unsigned char *)malloc(sizeof(unsigned char)*LINE);

char *p;


if (pf == NULL)

{

printf ("File open error!\n");

exit (0);

}

p = fgets(buf, LINE, pf);

while (p)

{

unsigned char *temp = decompression(buf);

fprintf(nf, "%s", temp);

free(temp);

free(buf);

buf = (char *)malloc(sizeof(char)*LINE);

p = fgets(buf, LINE, pf);

}

free(buf);

fclose(pf);

fclose(nf);



}


若1）中输入的3句话均以大写开头，则能顺利解压成原文，若为小写则后2句无法解压。个人觉得是我的解压函数有问题，望解答！

非常感谢！

[图灵狗]

晕，压缩处理的是字节流，不要与字符串再扯上任何关系，所以 fprintf(pf, "%s\n", temp)和p = fgets(buf, LINE, pf)这类的用法都是不正确的。应该在写入的时候先写长度再写内容，读取的时候先读长度再读内容，用fread和fwrite函数进行操作。

[whizer]

1)大写字母和小写字母压缩后的结果可能是不一样的. 2)你申请的是压缩后数据的2倍,这不一定能保证数据解压缩后内存够使,应该查找一下zlib的规范,好像从它的头部可以得到原数据的相关信息. 3)查一查zlib的格式,比较一下压缩后的文件和标准格式,debug一下.

[qq120848369]

这是最简单的接口了, 用用Feed类的接口把。

[ryfdizuo]

你按照这个流程试试： 压缩 写二进制文件 读二进制文件 解压缩

[图灵狗]

参见我的博文（http://blog.csdn.net/turingo/article/details/8178510）。

[图灵狗]

举个例子字符串"ABCD"缩过后，很有可能B变成了'\0'，这样你就只能写入"A"了；或者是结束符'\0'变成了'E'，这样字符串"ABCDExxxxxxxxx"就会一直延续下去，直到碰到偶然的'\0'

[asdk77]

谢谢各位！！！