/minizip

Minizip contrib in zlib with latest bug fixes that supports PKWARE disk spanning, AES encryption, and IO buffering

Primary LanguageCOtherNOASSERTION

Minizip zlib contribution that includes:

  • AES encryption
  • I/O buffering
  • PKWARE disk spanning
  • Visual Studio 2008 project files

It also has the latest bug fixes that having been found all over the internet including the minizip forum and zlib developer's mailing list.

AES Encryption

  • Requires #define HAVE_AES
  • Requires AES library files

When zipping with a password it will always use AES 256-bit encryption. When unzipping it will use AES decryption only if necessary.

I/O Buffering

Improves I/O performance by buffering read and write operations.

zlib_filefunc64_def filefunc64 = {0};
ourbuffer_t buffered = {0};
    
fill_win32_filefunc64(&buffered->filefunc64);
fill_buffer_filefunc64(&filefunc64, buffered);
    
unzOpen2_64(filename, &filefunc64)

PKWARE disk spanning

To create an archive with multiple disks use zipOpen3_64 supplying a disk_size value in bytes.

extern zipFile ZEXPORT zipOpen3_64 OF((const void *pathname, int append, 
  ZPOS64_T disk_size, zipcharpc* globalcomment, zlib_filefunc64_def* pzlib_filefunc_def));

The central directory is the only data stored in the .zip and doesn't follow disk_size restrictions.

When unzipping it will automatically determine when in needs to span disks.

I/O Memory

To unzip from a zip file in memory use fill_memory_filefunc and supply a proper ourmemory_t structure.

zlib_filefunc_def filefunc32 = {0};
ourmemory_t unzmem = {0};

unzmem.size = bufsize;
unzmem.base = (char *)malloc(unzmem.size);
memcpy(unzmem.base, buffer, unzmem.size);
    
fill_memory_filefunc(&filefunc32, &unzmem);

unzOpen2("__notused__", &filefunc32);

To create a zip file in memory use fill_memory_filefunc and supply a proper ourmemory_t structure. It is important not to forget to free zipmem->base when finished. If grow is set, zipmem->base will expand to fit the size of the zip. If grow is not set be sure to fill out zipmem.base and zipmem.size.

zlib_filefunc_def filefunc32 = {0};
ourmemory_t zipmem = {0};

zipmem.grow = 1;

fill_memory_filefunc(&filefunc32, &zipmem);

zipOpen3("__notused__", APPEND_STATUS_CREATE, 0, 0, &filefunc32);

BZIP2

  • Requires #define HAVE_BZIP2
  • Requires BZIP2 library

Windows RT

  • Requires #define IOWIN32_USING_WINRT_API