Add an API to unpack Zip files directly from and to file descriptors.

third_party/zlib/contrib/minizip/ioapi.c

 /* ioapi.h -- IO base function header for compress/uncompress .zip
    part of the MiniZip project - ( http://www.winimage.com/zLibDll/minizip.html )
 
          Copyright (C) 1998-2010 Gilles Vollant (minizip) ( http://www.winimage.com/zLibDll/minizip.html )
 
          Modifications for Zip64 support
          Copyright (C) 2009-2010 Mathias Svensson ( http://result42.com )
 
          For more info read MiniZip_info.txt
 
@@ skipping 98 matching lines @@
         mode_fopen = "r+b";
     else
     if (mode & ZLIB_FILEFUNC_MODE_CREATE)
         mode_fopen = "wb";
 
     if ((filename!=NULL) && (mode_fopen != NULL))
         file = fopen64((const char*)filename, mode_fopen);
     return file;
 }
 
+// Google
+voidpf ZCALLBACK fdopen_file_func (opaque, filename, mode)
+   voidpf opaque;
+   const char* filename;
+   int mode;
+{
+    FILE* file = NULL;
+    const char* mode_fopen = NULL;
+    if ((mode & ZLIB_FILEFUNC_MODE_READWRITEFILTER)==ZLIB_FILEFUNC_MODE_READ)
+        mode_fopen = "rb";
+    else
+    if (mode & ZLIB_FILEFUNC_MODE_EXISTING)
+        mode_fopen = "r+b";
+    else
+    if (mode & ZLIB_FILEFUNC_MODE_CREATE)
+        mode_fopen = "wb";
+
+    if ((filename!=NULL) && (mode_fopen != NULL))
+        file = fdopen(*(int*)opaque, mode_fopen);
+    return file;
+}
+
 
 static uLong ZCALLBACK fread_file_func (voidpf opaque, voidpf stream, void* buf, uLong size)
 {
     uLong ret;
     ret = (uLong)fread(buf, 1, (size_t)size, (FILE *)stream);
     return ret;
 }
 
 static uLong ZCALLBACK fwrite_file_func (voidpf opaque, voidpf stream, const void* buf, uLong size)
 {
@@ skipping 97 matching lines @@
 {
     pzlib_filefunc_def->zopen64_file = fopen64_file_func;
     pzlib_filefunc_def->zread_file = fread_file_func;
     pzlib_filefunc_def->zwrite_file = fwrite_file_func;
     pzlib_filefunc_def->ztell64_file = ftell64_file_func;
     pzlib_filefunc_def->zseek64_file = fseek64_file_func;
     pzlib_filefunc_def->zclose_file = fclose_file_func;
     pzlib_filefunc_def->zerror_file = ferror_file_func;
     pzlib_filefunc_def->opaque = NULL;
 }
+
+// Google
+void fill_fdopen_filefunc (zlib_filefunc_def* pzlib_filefunc_def, int fd)
+{
+    fill_fopen_filefunc(pzlib_filefunc_def);
+    pzlib_filefunc_def->zopen_file = fdopen_file_func;
+    int *ptr_fd = malloc(sizeof(int));
+    *ptr_fd = fd;
+    pzlib_filefunc_def->opaque = ptr_fd;
+}