vicroms / libzippp

C++ wrapper for libzip

libzippp

libzippp is a simple basic C++ wrapper around the libzip library. It is meant to be a portable and easy-to-use library for ZIP handling.

Compilation has been tested with:

• GCC 8.3.0 (GNU/Linux Debian)
• MS Visual Studio 2012 (Windows 7)

Underlying libraries:

• ZLib 1.2.11
• libzip 1.5.2

Compilation

LINUX

0. Make sure you have the following commands: g++ make tar wget
1. Download and compile the libraries (zlib and libzip) with the command: make libraries
2. Then create the static and shared libraries of libzippp: make
3. You may want to run the tests (optional): make tests (libbz2-dev package is needed to link statically)
4. Now you just have to include the src folder in your include path and link against libzippp.a or libzippp.so (do not forget to also link against libzip libraries in lib/libzip-1.5.2/lib/.libs/). An example of compilation with g++:

g++ -I./lib/libzip-1.5.2/lib -I./src \
    main.cpp libzippp.a \
    lib/libzip-1.5.2/lib/.libs/libzip.a \
    lib/zlib-1.2.11/libz.a

Encryption

Since version 1.5, libzip uses an underlying cryptographic library (OpenSSL, GNUTLS or CommonCrypto) that is necessary for static compilation. By default, libzippp will use -lssl -lcrypto (OpenSSL) as default flags to compile the tests. This can be changed by using make CRYPTO_FLAGS="-lsome_lib" LIBZIP_CMAKE="" tests.

Since libzip cmake's file detects automatically the cryptographic library to use, by default all the allowed libraries but OpenSSL are explicitely disabled in the LIBZIP_CMAKE variable in the Makefile.

See here for more information.

WINDOWS

From Stage 1 - Use prepared environment

0. Make sure you have cmake 3.10 (cmake.exe must be in the PATH) and MS Visual Studio 2012. The dev command prompt path (defined in compile.bat) should be:

<MSVS11>\Common7\Tools\VsDevCmd.bat

1. Download the libzip-<version>-windows-ready_to_compile.zip file from the release and extract it somewhere on your system. This will create a prepared structure, so libzippp can be compiled along with the needed libraries.

2. Simply execute the compile.bat file. This will compile zlib, libzip and finally libzippp.

3. You'll have a dist folder containing the release and debug folders where you can now execute the libzippp tests.

From Stage 0 - DIY

0. Make sure you have cmake 3.10 (cmake.exe must be in the PATH) and MS Visual Studio 2012. The dev command prompt path (defined in compile.bat) should be:

<MSVS11>\Common7\Tools\VsDevCmd.bat

1. Download libzip and zlib sources and extract them in the 'lib' folder. You should end up with the following structure:

libzippp/compile.bat
libzippp/lib/zlib-1.2.11
libzippp/lib/libzip-1.5.2

2. Apply the modifications described in libzippp/lib/libzip-1.5.2-windows.patch.

3. Execute the compile.bat (simply double-click on it). The compilation should go without error.

4. You'll have a dist folder containing the release and debug folders where you can now execute the libzippp tests.

5. You can either use libzippp.dll and libzippp.lib to link dynamically the library or simply use libzippp_static.lib to link it statically. Unless you also link zlib and libzippp statically, you'll need the dll packaged with your executable.

Usage

The API is meant to be very straight forward. Some french explanations can be found here.

How to list and read files in an archive:

#include "libzippp.h"
using namespace libzippp;

ZipArchive zf("archive.zip");
zf.open(ZipArchive::READ_ONLY);

vector<ZipEntry> entries = zf.getEntries();
vector<ZipEntry>::iterator it;
for(it=entries.begin() ; it!=entries.end(); ++it) {
  ZipEntry entry = *it;
  string name = entry.getName();
  int size = entry.getSize();

  //the length of binaryData will be size
  void* binaryData = entry.readAsBinary();

  //the length of textData will be size
  string textData = entry.readAsText();

  //...
}

zf.close();

How to read a specific entry from an archive:

#include "libzippp.h"
using namespace libzippp;

ZipArchive zf("archive.zip");
zf.open(ZipArchive::READ_ONLY);

//raw access
char* data = (char*)zf.readEntry("myFile.txt", true);
ZipEntry entry1 = zf.getEntry("myFile.txt");
string str1(data, entry1.getSize());

//text access
ZipEntry entry2 = zf.getEntry("myFile.txt");
string str2 = entry2.readAsText();

zf.close();

How to read a large entry from an archive:

#include "libzippp.h"
using namespace libzippp;

ZipArchive zf("archive.zip");
zf.open(ZipArchive::READ_ONLY);

ZipEntry largeEntry = z1.getEntry("largeentry");
std::ofstream ofUnzippedFile("largeFileContent.data");
largeEntry.readContent(ofUnzippedFile);
ofUnzippedFile.close();

zf.close();

How to add data to an archive:

#include "libzippp.h"
using namespace libzippp;

ZipArchive zf("archive.zip");
zf.open(ZipArchive::WRITE);
zf.addEntry("folder/subdir/");

const char* textData = "Hello,World!";
zf.addData("helloworld.txt", textData, 12);

zf.close();

How to remove data from an archive:

#include "libzippp.h"
using namespace libzippp;

ZipArchive zf("archive.zip");
zf.open(ZipArchive::WRITE);
zf.deleteEntry("myFile.txt");
zf.deleteEntry("myDir/subDir/");
zf.close();

Issues

LINUX

You might already have libzip compiled elsewhere on your system. Hence, you don't need to run 'make libzip'. Instead, just put the libzip location when you compile libzipp:

make LIBZIP=path/to/libzip

Under Debian, you'll have to install the package zlib1g-dev in order to compile if you don't want to install zlib manually.

WINDOWS

By default, MS Visual Studio 2012 is installed under the following path:

C:\Program Files (x86)\Microsoft Visual Studio 11.0\

Be aware that non-virtual-only classes are shared within the DLL of libzippp. Hence you'll need to use the same compiler for libzippp and the pieces of code that will use it. To avoid this issue, you'll have to link the library statically.

More information here.

Static linkage

Extra explanations can be found here.