use zlib lib to compress or decompress file
If you want to compress or decompress file when writing C++ code,you can choose zlib library,that's quite easy.
1,Download zlib library's code form website:http://zlib.net/
2,Decompress the file you've downloaded,and then go to the directory "zlib-1.2.11\zlib-1.2.11\contrib\vstudio\vc14", open the zlibvc.sln in it with your vs.
3,Now you have opened the project of zlib,you need to compile it next.rebuild the project named "zlibvc",there are errors:
1> The system cannot find the path specified.
1> 'bld_ml64.bat' is not recognized as an internal or external command,
1> operable program or batch file.
1>C:\Program Files (x86)\MSBuild\Microsoft.Cpp\v4.0\V140\Microsoft.CppCommon.targets(123,5): error MSB3073: The command "cd ..\..\contrib\masmx64
1>C:\Program Files (x86)\MSBuild\Microsoft.Cpp\v4.0\V140\Microsoft.CppCommon.targets(123,5): error MSB3073: bld_ml64.bat
1>C:\Program Files (x86)\MSBuild\Microsoft.Cpp\v4.0\V140\Microsoft.CppCommon.targets(123,5): error MSB3073: :VCEnd" exited with code 9009.
========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ==========
4,you need to reset the Properties of the project,select Build Event,then select Pre-Build Event,then delete the content of Command Line on it.rewrite the command line with your zlib's path.for example:
C:
cd C:\Users\sonne\Desktop\zlib-1.2.11\zlib-1.2.11\contrib\masmx64
bld_ml64.bat
so 'C:\Users\sonne\Desktop\zlib-1.2.11' is the path where I put my zlib downloaded form website before.
5,compile again,rebuild your project,now succeed.
After compiling zlib library,now need to use the dll.
1,put the zlibwapi.dll and zlibwapi.lib in your project.
2,you also need to include the zlib.h and zconf.h.
3,add a line in cpp file:
#pragma comment(lib,"zlibwapi.lib")
4,now you can use zlib APIs.
here is zlib usage examples: https://zlib.net/zlib_how.html
the manual is also useful: https://zlib.net/manual.html
5, my test code here,shows how to compress and decompress by zlib:
#include <stdio.h>
#include <string.h>
#include <assert.h>
#include "zlib.h" #define CHUNK 16384
#pragma comment(lib,"zlibwapi.lib") int def(FILE *source, FILE *dest, int level)
{
int ret, flush;
unsigned have;
z_stream strm;
unsigned char in[CHUNK];
unsigned char out[CHUNK];
/* allocate deflate state */
strm.zalloc = Z_NULL;
strm.zfree = Z_NULL;
strm.opaque = Z_NULL;
ret = deflateInit(&strm, level);
if (ret != Z_OK)
return ret;
/* compress until end of file */
do {
strm.avail_in = fread(in, , CHUNK, source);
if (ferror(source)) {
(void)deflateEnd(&strm);
return Z_ERRNO;
}
flush = feof(source) ? Z_FINISH : Z_NO_FLUSH;
strm.next_in = in;
/* run deflate() on input until output buffer not full, finish
compression if all of source has been read in */
do {
strm.avail_out = CHUNK;
strm.next_out = out;
ret = deflate(&strm, flush); /* no bad return value */
assert(ret != Z_STREAM_ERROR); /* state not clobbered */
have = CHUNK - strm.avail_out;
if (fwrite(out, , have, dest) != have || ferror(dest)) {
(void)deflateEnd(&strm);
return Z_ERRNO;
}
} while (strm.avail_out == );
assert(strm.avail_in == ); /* all input will be used */
/* done when last data in file processed */
} while (flush != Z_FINISH);
assert(ret == Z_STREAM_END); /* stream will be complete */
/* clean up and return */
(void)deflateEnd(&strm);
return Z_OK;
} int inf(FILE *source, FILE *dest)
{
int ret;
unsigned have;
z_stream strm;
unsigned char in[CHUNK];
unsigned char out[CHUNK];
/* allocate inflate state */
strm.zalloc = Z_NULL;
strm.zfree = Z_NULL;
strm.opaque = Z_NULL;
strm.avail_in = ;
strm.next_in = Z_NULL;
ret = inflateInit(&strm);
if (ret != Z_OK)
return ret;
/* decompress until deflate stream ends or end of file */
do {
strm.avail_in = fread(in, , CHUNK, source);
if (ferror(source)) {
(void)inflateEnd(&strm);
return Z_ERRNO;
}
if (strm.avail_in == )
break;
strm.next_in = in;
/* run inflate() on input until output buffer not full */
do {
strm.avail_out = CHUNK;
strm.next_out = out;
ret = inflate(&strm, Z_NO_FLUSH);
assert(ret != Z_STREAM_ERROR); /* state not clobbered */
switch (ret) {
case Z_NEED_DICT:
ret = Z_DATA_ERROR; /* and fall through */
case Z_DATA_ERROR:
case Z_MEM_ERROR:
(void)inflateEnd(&strm);
return ret;
}
have = CHUNK - strm.avail_out;
if (fwrite(out, , have, dest) != have || ferror(dest)) {
(void)inflateEnd(&strm);
return Z_ERRNO;
}
} while (strm.avail_out == );
/* done when inflate() says it's done */
} while (ret != Z_STREAM_END);
/* clean up and return */
(void)inflateEnd(&strm);
return ret == Z_STREAM_END ? Z_OK : Z_DATA_ERROR;
} int main() {
FILE *fp_src;
FILE *fp_dst; //compress a file
//fp_src = fopen( "test.txt", "r" );
//fp_dst = fopen( "myzip.zip", "w" );
//int ret = def(fp_src,fp_dst,9); //decompress a file compressed
fp_src = fopen( "myzip.zip", "r" );
fp_dst = fopen( "test2.txt", "w");
int ret = inf(fp_src, fp_dst); return ;
}
use zlib lib to compress or decompress file的更多相关文章
- cloudera-scm-server启动时出现Caused by: java.io.FileNotFoundException: /var/lib/cloudera-scm-server/.keystore (No such file or directory)问题解决方法(图文详解)
不多说,直接上干货! 问题详情 查看/var/log/cloudera-scm-server.log的启动日志 问题来源 我在用cloudermanager安装好之后,然后,在对如下. 配置kerbe ...
- Starting MySQL ** mysqld_safe Directory '/var/lib/mysql' for UNIX socket file don't exists
本地虚拟机(CentOS6.8)启动MySQL(MySQL5.6.35)服务失败 [root@VMUest ~]# service mysql status ERROR! MySQL is not r ...
- error while loading shared libraries: lib******: cannot open shared object file: No such file or directory
程序编译成功后,运行时错误: error while loading shared libraries: libevent-2.0.so.5: cannot open shared object fi ...
- Compress and decompress string
You are given a string with lower case letters only. Compress it by putting the count of the letter ...
- failed to create rwlayer: lstat /var/lib/docker/overlay2/ no such file or directory
在使用Docker构建微服务镜像时出现的错误.第一天构建好好的,第二天就出现了这样的错误.通过百度这条错误的信息非常少,只在 stackoverflow.com 上找到一条,问题指向了 dockerf ...
- C# GZip Compress DeCompress
using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.T ...
- Zlib库的安装与使用
在实际应用中经常会遇到要压缩数据的问题,常见的压缩格式有zip和rar,而Linux下那就更多了,bz2,gz,xz什么的都有,单单Linux下的解压和压缩命令就有好多呢?没有什么好不好的.查了资料, ...
- 【VC++技术杂谈008】使用zlib解压zip压缩文件
最近因为项目的需要,要对zip压缩文件进行批量解压.在网上查阅了相关的资料后,最终使用zlib开源库实现了该功能.本文将对zlib开源库进行简单介绍,并给出一个使用zlib开源库对zip压缩文件进行解 ...
- [充电][库]Zlib文件压缩和解压
原文链接: http://www.cnblogs.com/fairycao/archive/2009/12/09/1620414.html 开源代码:http://www.zlib.net/zlib使 ...
随机推荐
- 献给迷惘的Java架构工程师
1. 工程化专题 (团队大于3个人之后,你需要去考虑团队合作,科学管理) 2. 源码分析专题 (好的程序员,一行代码一个设计就能看出来,源码分析带你品味代码,感受架构) 3.高性能及分布式专题 ( ...
- HDU 4010 Query on The Trees
Problem Description We have met so many problems on the tree, so today we will have a query problem ...
- HDU 2639 Bone Collector II(01背包变形【第K大最优解】)
Bone Collector II Time Limit: 5000/2000 MS (Java/Others) Memory Limit: 32768/32768 K (Java/Others ...
- How Many Sets I(容斥定理)
题目链接:http://acm.zju.edu.cn/onlinejudge/showProblem.do?problemCode=3556 How Many Sets I Time Limit: 2 ...
- 独立成分分析(ICA)的模拟实验(R语言)
本笔记是ESL14.7节图14.42的模拟过程.第一部分将以ProDenICA法为例试图介绍ICA的整个计算过程:第二部分将比较ProDenICA.FastICA以及KernelICA这种方法,试图重 ...
- JDBC连接数据库(查询)的步骤
先导入jar包 代码: import java.sql.Connection;import java.sql.DriverManager;import java.sql.ResultSet;impor ...
- LinkedHashMap 源码详细分析(JDK1.8)
1. 概述 LinkedHashMap 继承自 HashMap,在 HashMap 基础上,通过维护一条双向链表,解决了 HashMap 不能随时保持遍历顺序和插入顺序一致的问题.除此之外,Linke ...
- light oj 1184 Marriage Media
题目: You run a marriage media. You take some profiles for men and women, and your task is to arrange ...
- Spring MVC集成Swagger
什么是Swagger? 大部分 Web 应用程序都支持 RESTful API,但不同于 SOAP API——REST API 依赖于 HTTP 方法,缺少与 Web 服务描述语言(Web Servi ...
- 从零开始学习前端JAVASCRIPT — 5、JavaScript基础BOM
1:BOM(Browser Object Model)概念 window对象是BOM中所有对象的核心. 2:window属性(较少用) self:self代表自己,相当于window. windo ...