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@nutbread /Zipper.js Secret
Last active Sep 23, 2016

What would you like to do?
Javascript to put data into a storage zip file (no compression)
// Test
var zw = new Zipper(),
fi, url;
zw.set_comment("");
fi = zw.add_file(zw.string_to_array("test1あ"), "test1あ.txt");
zw.set_file_comment(fi, "");
zw.set_file_extra(fi, "");
fi = zw.add_file(zw.string_to_array("test2あ"), "test2あ.txt");
zw.set_file_comment(fi, "2あ");
zw.set_file_extra(fi, "2あ");
zw.set_file_date(fi, new Date(1981, 10, 10));
zw.set_file_data(fi, "test3あ");
zw.set_file_name(fi, "test3あ.txt");
url = URL.createObjectURL(zw.to_blob());
document.body.innerHTML = '<a href="' + url + '" target=_blank download="test.zip">test</a>';
var Zipper = (function () {
var Zipper = function () {
this.files = [];
this.comment = "";
this.comment_data = string_to_array(this.comment, max_lengths.comment);
this.date = new Date();
};
var max_lengths = {
data: 0XFFFFFFFF,
name: 0xFFFF,
extra: 0xFFFF,
comment: 0xFFFF,
};
var signatures = {
file: new Uint8Array([ 0x50 , 0x4B , 0x03 , 0x04 ]),
cd: new Uint8Array([ 0x50 , 0x4B , 0x01 , 0x02 ]),
footer: new Uint8Array([ 0x50 , 0x4B , 0x05 , 0x06 ]),
};
var data_sizes = {
file: 26, // 30 - 4
cd: 42, // 46 - 4
footer: 18, // 22 - 4
};
var ZIP_FLAG_UTF8 = 1 << 11;
var typeof_str = typeof("");
var FileData = function (data, filename, extra, comment, date) {
// Setup
this.set_data(data);
this.set_name(filename);
this.set_extra(extra);
this.set_comment(comment);
this.set_date(date);
// Other stuff
this.offset = 0;
this.crc = null;
this.utf8 = true;
};
FileData.prototype = {
constructor: FileData,
prepare: function (offset) {
this.offset = offset;
this.utf8 = (
this.name.length != this.name_data.length ||
this.extra.length != this.extra_data.length ||
this.comment.length != this.comment_data.length
);
if (this.crc === null) {
this.crc = crc32(this.data);
}
},
set_data: function (data) {
if (typeof(data) == typeof_str) {
// Convert to array
this.data = string_to_array(data, max_lengths.data);
}
else {
// Set and truncate if necessary
this.data = data;
if (this.data.length > max_lengths.data) {
this.data = this.data.subarray(0, max_lengths.data);
}
}
this.crc = null;
},
set_name: function (filename) {
this.name = filename;
this.name_data = string_to_array(this.name, max_lengths.name);
},
set_extra: function (extra) {
this.extra = extra;
this.extra_data = string_to_array(this.extra, max_lengths.extra);
},
set_comment: function (comment) {
this.comment = comment;
this.comment_data = string_to_array(this.comment, max_lengths.comment);
},
set_date: function (date) {
this.date = date;
this.date_zip = date_to_ziptime(this.date);
},
};
var BufferWriter = function (buffer) {
this.buffer = buffer;
this.pos = 0;
};
BufferWriter.prototype = {
constructor: BufferWriter,
reset: function (buffer) {
this.buffer = buffer;
this.pos = 0;
},
write_ushort: function (value) {
// Bound
value = (value & 0x0000FFFF) >>> 0;
// Write
for (var i = 0; i < 2; ++i) {
this.buffer[this.pos++] = value & 0xFF;
value = value >>> 8;
}
},
write_uint: function (value) {
// Bound
value = (value & 0xFFFFFFFF) >>> 0;
// Write
for (var i = 0; i < 4; ++i) {
this.buffer[this.pos++] = value & 0xFF;
value = value >>> 8;
}
},
write_data: function (data) {
// Write
for (var i = 0, len = data.length; i < len; ++i) {
this.buffer[this.pos++] = data[i];
}
},
write_string: function (str) {
// Write
for (var i = 0, len = str.length; i < len; ++i) {
this.buffer[this.pos++] = str.charCodeAt(i);
}
},
};
var crc32 = (function () {
var crc_table = new Uint32Array([ //{
0x00000000, 0x77073096, 0xEE0E612C, 0x990951BA, 0x076DC419, 0x706AF48F, 0xE963A535, 0x9E6495A3,
0x0EDB8832, 0x79DCB8A4, 0xE0D5E91E, 0x97D2D988, 0x09B64C2B, 0x7EB17CBD, 0xE7B82D07, 0x90BF1D91,
0x1DB71064, 0x6AB020F2, 0xF3B97148, 0x84BE41DE, 0x1ADAD47D, 0x6DDDE4EB, 0xF4D4B551, 0x83D385C7,
0x136C9856, 0x646BA8C0, 0xFD62F97A, 0x8A65C9EC, 0x14015C4F, 0x63066CD9, 0xFA0F3D63, 0x8D080DF5,
0x3B6E20C8, 0x4C69105E, 0xD56041E4, 0xA2677172, 0x3C03E4D1, 0x4B04D447, 0xD20D85FD, 0xA50AB56B,
0x35B5A8FA, 0x42B2986C, 0xDBBBC9D6, 0xACBCF940, 0x32D86CE3, 0x45DF5C75, 0xDCD60DCF, 0xABD13D59,
0x26D930AC, 0x51DE003A, 0xC8D75180, 0xBFD06116, 0x21B4F4B5, 0x56B3C423, 0xCFBA9599, 0xB8BDA50F,
0x2802B89E, 0x5F058808, 0xC60CD9B2, 0xB10BE924, 0x2F6F7C87, 0x58684C11, 0xC1611DAB, 0xB6662D3D,
0x76DC4190, 0x01DB7106, 0x98D220BC, 0xEFD5102A, 0x71B18589, 0x06B6B51F, 0x9FBFE4A5, 0xE8B8D433,
0x7807C9A2, 0x0F00F934, 0x9609A88E, 0xE10E9818, 0x7F6A0DBB, 0x086D3D2D, 0x91646C97, 0xE6635C01,
0x6B6B51F4, 0x1C6C6162, 0x856530D8, 0xF262004E, 0x6C0695ED, 0x1B01A57B, 0x8208F4C1, 0xF50FC457,
0x65B0D9C6, 0x12B7E950, 0x8BBEB8EA, 0xFCB9887C, 0x62DD1DDF, 0x15DA2D49, 0x8CD37CF3, 0xFBD44C65,
0x4DB26158, 0x3AB551CE, 0xA3BC0074, 0xD4BB30E2, 0x4ADFA541, 0x3DD895D7, 0xA4D1C46D, 0xD3D6F4FB,
0x4369E96A, 0x346ED9FC, 0xAD678846, 0xDA60B8D0, 0x44042D73, 0x33031DE5, 0xAA0A4C5F, 0xDD0D7CC9,
0x5005713C, 0x270241AA, 0xBE0B1010, 0xC90C2086, 0x5768B525, 0x206F85B3, 0xB966D409, 0xCE61E49F,
0x5EDEF90E, 0x29D9C998, 0xB0D09822, 0xC7D7A8B4, 0x59B33D17, 0x2EB40D81, 0xB7BD5C3B, 0xC0BA6CAD,
0xEDB88320, 0x9ABFB3B6, 0x03B6E20C, 0x74B1D29A, 0xEAD54739, 0x9DD277AF, 0x04DB2615, 0x73DC1683,
0xE3630B12, 0x94643B84, 0x0D6D6A3E, 0x7A6A5AA8, 0xE40ECF0B, 0x9309FF9D, 0x0A00AE27, 0x7D079EB1,
0xF00F9344, 0x8708A3D2, 0x1E01F268, 0x6906C2FE, 0xF762575D, 0x806567CB, 0x196C3671, 0x6E6B06E7,
0xFED41B76, 0x89D32BE0, 0x10DA7A5A, 0x67DD4ACC, 0xF9B9DF6F, 0x8EBEEFF9, 0x17B7BE43, 0x60B08ED5,
0xD6D6A3E8, 0xA1D1937E, 0x38D8C2C4, 0x4FDFF252, 0xD1BB67F1, 0xA6BC5767, 0x3FB506DD, 0x48B2364B,
0xD80D2BDA, 0xAF0A1B4C, 0x36034AF6, 0x41047A60, 0xDF60EFC3, 0xA867DF55, 0x316E8EEF, 0x4669BE79,
0xCB61B38C, 0xBC66831A, 0x256FD2A0, 0x5268E236, 0xCC0C7795, 0xBB0B4703, 0x220216B9, 0x5505262F,
0xC5BA3BBE, 0xB2BD0B28, 0x2BB45A92, 0x5CB36A04, 0xC2D7FFA7, 0xB5D0CF31, 0x2CD99E8B, 0x5BDEAE1D,
0x9B64C2B0, 0xEC63F226, 0x756AA39C, 0x026D930A, 0x9C0906A9, 0xEB0E363F, 0x72076785, 0x05005713,
0x95BF4A82, 0xE2B87A14, 0x7BB12BAE, 0x0CB61B38, 0x92D28E9B, 0xE5D5BE0D, 0x7CDCEFB7, 0x0BDBDF21,
0x86D3D2D4, 0xF1D4E242, 0x68DDB3F8, 0x1FDA836E, 0x81BE16CD, 0xF6B9265B, 0x6FB077E1, 0x18B74777,
0x88085AE6, 0xFF0F6A70, 0x66063BCA, 0x11010B5C, 0x8F659EFF, 0xF862AE69, 0x616BFFD3, 0x166CCF45,
0xA00AE278, 0xD70DD2EE, 0x4E048354, 0x3903B3C2, 0xA7672661, 0xD06016F7, 0x4969474D, 0x3E6E77DB,
0xAED16A4A, 0xD9D65ADC, 0x40DF0B66, 0x37D83BF0, 0xA9BCAE53, 0xDEBB9EC5, 0x47B2CF7F, 0x30B5FFE9,
0xBDBDF21C, 0xCABAC28A, 0x53B39330, 0x24B4A3A6, 0xBAD03605, 0xCDD70693, 0x54DE5729, 0x23D967BF,
0xB3667A2E, 0xC4614AB8, 0x5D681B02, 0x2A6F2B94, 0xB40BBE37, 0xC30C8EA1, 0x5A05DF1B, 0x2D02EF8D,
]); //}
return function (data) {
var crc = (0 ^ (-1)),
data_len = data.length,
ct = crc_table,
i;
for (i = 0; i < data_len; ++i) {
crc = (crc >>> 8) ^ ct[(crc ^ data[i]) & 0xFF];
}
return (crc ^ (-1)) >>> 0;
};
})();
var date_to_ziptime = function (date) {
return [
(date.getDate()) | ((date.getMonth() + 1) << 5) | ((date.getFullYear() - 1980) << 9), // Date
Math.floor(date.getSeconds() / 2) | (date.getMinutes() << 5) | (date.getHours() << 11) // Time
];
};
var array_to_string = function (arr) {
// Copy
var str = "",
len = arr.length,
chunk_size = 1024,
i;
for (i = 0; i < len; i += chunk_size) {
str += String.fromCharCode.apply(null, arr.subarray(i, i + chunk_size));
}
// Decode uft-8
return decodeURIComponent(escape(str));
};
var string_to_array = function (str, max_length) {
// Encode to uft-8
str = unescape(encodeURIComponent(str));
// Copy
var len = str.length,
buffer, i;
if (max_length !== undefined && len > max_length) len = max_length;
buffer = new Uint8Array(len);
for (i = 0; i < len; ++i) {
buffer[i] = str.charCodeAt(i);
}
// Done
return buffer;
};
var write_file_header = function (writer, file_data) {
// Write the file header
writer.write_ushort(20); // Version
writer.write_ushort(file_data.utf8 ? ZIP_FLAG_UTF8 : 0); // Flags
writer.write_ushort(0); // Compression (store)
writer.write_ushort(file_data.date_zip[1]); // Modified time
writer.write_ushort(file_data.date_zip[0]); // Modified date
writer.write_uint(file_data.crc); // CRC32
writer.write_uint(file_data.data.length); // Compressed size
writer.write_uint(file_data.data.length); // Unompressed size
writer.write_ushort(file_data.name_data.length); // Filename length
writer.write_ushort(file_data.extra_data.length); // Extra length
};
var write_central_directory_header = function (writer, file_data) {
// Write the central directory header
writer.write_ushort(20); // Version
writer.write_ushort(20); // Version required
writer.write_ushort(file_data.utf8 ? ZIP_FLAG_UTF8 : 0); // Flags
writer.write_ushort(0); // Compression (store)
writer.write_ushort(file_data.date_zip[1]); // Modified time
writer.write_ushort(file_data.date_zip[0]); // Modified date
writer.write_uint(file_data.crc); // CRC32
writer.write_uint(file_data.data.length); // Compressed size
writer.write_uint(file_data.data.length); // Unompressed size
writer.write_ushort(file_data.name_data.length); // Filename length
writer.write_ushort(file_data.extra_data.length); // Extra length
writer.write_ushort(file_data.comment_data.length); // Comment length
writer.write_ushort(0); // Disk number start
writer.write_ushort(0); // Internal attr
writer.write_uint(0); // External attr
writer.write_uint(file_data.offset); // Offset
};
var write_footer = function (writer, file_count, pos_cd, pos_footer) {
// Write file footer
writer.write_ushort(0); // Disk number
writer.write_ushort(0); // Disk number with central directory
writer.write_ushort(file_count); // Disk entries
writer.write_ushort(file_count); // Total entries
writer.write_uint(pos_footer - pos_cd); // Central directory size
writer.write_uint(pos_cd); // Central directory start
writer.write_ushort(this.comment_data.length); // Comment length
};
Zipper.array_to_string = array_to_string;
Zipper.string_to_array = string_to_array;
Zipper.prototype = {
constructor: Zipper,
calculate_size: function () {
var total_size = 0,
file_count = this.files.length,
i, f;
// Calculate size
for (i = 0; i < file_count; ++i) {
f = this.files[i];
total_size += signatures.file.length + data_sizes.file + f.name_data.length + f.extra_data.length + f.data.length; // Entry
total_size += signatures.cd.length + data_sizes.cd + f.name_data.length + f.extra_data.length + f.comment_data.length; // Central directory
}
// Footer length
total_size += signatures.footer.length + data_sizes.footer + this.comment_data.length;
// Done
return total_size;
},
set_date: function (date) {
this.date = date;
},
get_date: function () {
return this.date;
},
set_comment: function (str) {
this.comment = str;
this.comment_data = string_to_array(this.comment, max_lengths.comment);
},
get_comment: function () {
return this.comment;
},
add_file: function (data, filename) {
// Create
var file_data = new FileData(data, filename, "", "", this.date);
// Add
this.files.push(file_data);
// Done
return this.files.length - 1;
},
remove_file: function (index) {
this.files.splice(index, 1);
},
get_file_count: function () {
return this.files.length;
},
get_file_data: function (index) {
return this.files[index].data;
},
set_file_data: function (index, data) {
this.files[index].set_data(data);
},
get_file_name: function (index) {
return this.files[index].name;
},
set_file_name: function (index, name) {
this.files[index].set_name(name);
},
get_file_extra: function (index) {
return this.files[index].extra;
},
set_file_extra: function (index, extra) {
this.files[index].set_extra(extra);
},
get_file_comment: function (index) {
return this.files[index].comment;
},
set_file_comment: function (index, comment) {
this.files[index].set_comment(comment);
},
get_file_date: function (index) {
return this.files[index].date;
},
set_file_date: function (index, date) {
this.files[index].set_date(date);
},
to_buffer: function () {
var total_size = this.calculate_size(),
file_count = this.files.length,
bw = new BufferWriter(new Uint8Array(total_size)),
pos_cd, pos_footer, i, f;
// Write file data
for (i = 0; i < file_count; ++i) {
f = this.files[i];
f.prepare(bw.pos);
// Header
bw.write_data(signatures.file); // Signature
write_file_header.call(this, bw, f);
// Data
bw.write_data(f.name_data); // Name
bw.write_data(f.extra_data); // Extra
bw.write_data(f.data); // Data
}
// Central directory
pos_cd = bw.pos;
for (i = 0; i < file_count; ++i) {
f = this.files[i];
// Entry
bw.write_data(signatures.cd); // Signature
write_central_directory_header.call(this, bw, f);
// Data
bw.write_data(f.name_data); // Name
bw.write_data(f.extra_data); // Extra
bw.write_data(f.comment_data); // Comment
}
// Footer
pos_footer = bw.pos;
bw.write_data(signatures.footer); // Signature
write_footer.call(this, bw, file_count, pos_cd, pos_footer);
bw.write_data(this.comment_data); // Comment
// Done
return bw.buffer;
},
to_blob: function () {
var file_count = this.files.length,
data_array = [],
bw = new BufferWriter(),
pos = 0,
pos_cd, i, f;
// Write file data
for (i = 0; i < file_count; ++i) {
f = this.files[i];
f.prepare(pos);
// Header
bw.reset(new Uint8Array(data_sizes.file));
write_file_header.call(this, bw, f);
data_array.push(signatures.file); // Signature
data_array.push(bw.buffer);
// Data
data_array.push(f.name_data); // Name
data_array.push(f.extra_data); // Extra
data_array.push(f.data); // Data
// Pos update
pos += signatures.file.length + bw.buffer.length + f.name_data.length + f.extra_data.length + f.data.length;
}
// Central directory
pos_cd = pos;
for (i = 0; i < file_count; ++i) {
f = this.files[i];
// Header
bw.reset(new Uint8Array(data_sizes.cd));
write_central_directory_header.call(this, bw, f);
data_array.push(signatures.cd); // Signature
data_array.push(bw.buffer);
// Data
data_array.push(f.name_data); // Name
data_array.push(f.extra_data); // Extra
data_array.push(f.comment_data); // Comment
// Pos update
pos += signatures.cd.length + bw.buffer.length + f.name_data.length + f.extra_data.length + f.comment_data.length;
}
// Footer
bw.reset(new Uint8Array(data_sizes.footer));
write_footer.call(this, bw, file_count, pos_cd, pos);
data_array.push(signatures.footer); // Signature
data_array.push(bw.buffer);
data_array.push(this.comment_data); // Comment
// Create as a blob
return new Blob(data_array, { type: "application/zip" });
},
};
return Zipper;
})();
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