https://fubar.com/js/canvasResize/binaryajax.js

1
2/*
3 * Binary Ajax 0.1.10
4 * Copyright (c) 2008 Jacob Seidelin, [email protected], http://blog.nihilogic.dk/
5 * Licensed under the MPL License [http://www.nihilogic.dk/licenses/mpl-license.txt]
6 */
7
8var BinaryFile = function(strData, iDataOffset, iDataLength) {
9    var data = strData;
10    var dataOffset = iDataOffset || 0;
11    var dataLength = 0;
12
13    this.getRawData = function() {
14        return data;
15    }
16
17    if (typeof strData == "string") {
18        dataLength = iDataLength || data.length;
19
20        this.getByteAt = function(iOffset) {
21            return data.charCodeAt(iOffset + dataOffset) & 0xFF;
22        }
23
24        this.getBytesAt = function(iOffset, iLength) {
25            var aBytes = [];
26
27            for (var i = 0; i < iLength; i++) {
28                aBytes[i] = data.charCodeAt((iOffset + i) + dataOffset) & 0xFF
29            }
30            ;
31
32            return aBytes;
33        }
34    } else if (typeof strData == "unknown") {
35        dataLength = iDataLength || IEBinary_getLength(data);
36
37        this.getByteAt = function(iOffset) {
38            return IEBinary_getByteAt(data, iOffset + dataOffset);
39        }
40
41        this.getBytesAt = function(iOffset, iLength) {
42            return new VBArray(IEBinary_getBytesAt(data, iOffset + dataOffset, iLength)).toArray();
43        }
44    }
45
46    this.getLength = function() {
47        return dataLength;
48    }
49
50    this.getSByteAt = function(iOffset) {
51        var iByte = this.getByteAt(iOffset);
52        if (iByte > 127)
53            return iByte - 256;
54        else
55            return iByte;
56    }
57
58    this.getShortAt = function(iOffset, bBigEndian) {
59        var iShort = bBigEndian ?
60                (this.getByteAt(iOffset) << 8) + this.getByteAt(iOffset + 1)
61                : (this.getByteAt(iOffset + 1) << 8) + this.getByteAt(iOffset)
62        if (iShort < 0)
63            iShort += 65536;
64        return iShort;
65    }
66    this.getSShortAt = function(iOffset, bBigEndian) {
67        var iUShort = this.getShortAt(iOffset, bBigEndian);
68        if (iUShort > 32767)
69            return iUShort - 65536;
70        else
71            return iUShort;
72    }
73    this.getLongAt = function(iOffset, bBigEndian) {
74        var iByte1 = this.getByteAt(iOffset),
75                iByte2 = this.getByteAt(iOffset + 1),
76                iByte3 = this.getByteAt(iOffset + 2),
77                iByte4 = this.getByteAt(iOffset + 3);
78
79        var iLong = bBigEndian ?
80                (((((iByte1 << 8) + iByte2) << 8) + iByte3) << 8) + iByte4
81                : (((((iByte4 << 8) + iByte3) << 8) + iByte2) << 8) + iByte1;
82        if (iLong < 0)
83            iLong += 4294967296;
84        return iLong;
85    }
86    this.getSLongAt = function(iOffset, bBigEndian) {
87        var iULong = this.getLongAt(iOffset, bBigEndian);
88        if (iULong > 2147483647)
89            return iULong - 4294967296;
90        else
91            return iULong;
92    }
93
94    this.getStringAt = function(iOffset, iLength) {
95        var aStr = [];
96
97        var aBytes = this.getBytesAt(iOffset, iLength);
98        for (var j = 0; j < iLength; j++) {
99            aStr[j] = String.fromCharCode(aBytes[j]);
100        }
101        return aStr.join("");
102    }
103
104    this.getCharAt = function(iOffset) {
105        return String.fromCharCode(this.getByteAt(iOffset));
106    }
107    this.toBase64 = function() {
108        return window.btoa(data);
109    }
110    this.fromBase64 = function(strBase64) {
111        data = window.atob(strBase64);
112    }
113}
114
115
116var BinaryAjax = (function() {
117
118    function createRequest() {
119        var oHTTP = null;
120        if (window.ActiveXObject) {
121            oHTTP = new ActiveXObject("Microsoft.XMLHTTP");
122        } else if (window.XMLHttpRequest) {
123            oHTTP = new XMLHttpRequest();
124        }
125        return oHTTP;
126    }
127
128    function getHead(strURL, fncCallback, fncError) {
129        var oHTTP = createRequest();
130        if (oHTTP) {
131            if (fncCallback) {
132                if (typeof(oHTTP.onload) != "undefined") {
133                    oHTTP.onload = function() {
134                        if (oHTTP.status == "200") {
135                            fncCallback(this);
136                        } else {
137                            if (fncError)
138                                fncError();
139                        }
140                        oHTTP = null;
141                    };
142                } else {
143                    oHTTP.onreadystatechange = function() {
144                        if (oHTTP.readyState == 4) {
145                            if (oHTTP.status == "200") {
146                                fncCallback(this);
147                            } else {
148                                if (fncError)
149                                    fncError();
150                            }
151                            oHTTP = null;
152                        }
153                    };
154                }
155            }
156            oHTTP.open("HEAD", strURL, true);
157            oHTTP.send(null);
158        } else {
159            if (fncError)
160                fncError();
161        }
162    }
163
164    function sendRequest(strURL, fncCallback, fncError, aRange, bAcceptRanges, iFileSize) {
165        var oHTTP = createRequest();
166        if (oHTTP) {
167
168            var iDataOffset = 0;
169            if (aRange && !bAcceptRanges) {
170                iDataOffset = aRange[0];
171            }
172            var iDataLen = 0;
173            if (aRange) {
174                iDataLen = aRange[1] - aRange[0] + 1;
175            }
176
177            if (fncCallback) {
178                if (typeof(oHTTP.onload) != "undefined") {
179                    oHTTP.onload = function() {
180                        if (oHTTP.status == "200" || oHTTP.status == "206" || oHTTP.status == "0") {
181                            oHTTP.binaryResponse = new BinaryFile(oHTTP.responseText, iDataOffset, iDataLen);
182                            oHTTP.fileSize = iFileSize || oHTTP.getResponseHeader("Content-Length");
183                            fncCallback(oHTTP);
184                        } else {
185                            if (fncError)
186                                fncError();
187                        }
188                        oHTTP = null;
189                    };
190                } else {
191                    oHTTP.onreadystatechange = function() {
192                        if (oHTTP.readyState == 4) {
193                            if (oHTTP.status == "200" || oHTTP.status == "206" || oHTTP.status == "0") {
194                                // IE6 craps if we try to extend the XHR object
195                                var oRes = {
196                                    status: oHTTP.status,
197                                    // IE needs responseBody, Chrome/Safari needs responseText
198                                    binaryResponse: new BinaryFile(
199                                            typeof oHTTP.responseBody == "unknown" ? oHTTP.responseBody : oHTTP.responseText, iDataOffset, iDataLen
200                                            ),
201                                    fileSize: iFileSize || oHTTP.getResponseHeader("Content-Length")
202                                };
203                                fncCallback(oRes);
204                            } else {
205                                if (fncError)
206                                    fncError();
207                            }
208                            oHTTP = null;
209                        }
210                    };
211                }
212            }
213            oHTTP.open("GET", strURL, true);
214
215            if (oHTTP.overrideMimeType)
216                oHTTP.overrideMimeType('text/plain;

216 charset=x-user-defined');
217
218            if (aRange && bAcceptRanges) {
219                oHTTP.setRequestHeader("Range", "bytes=" + aRange[0] + "-" + aRange[1]);
220            }
221
222            oHTTP.setRequestHeader("If-Modified-Since", "Sat, 1 Jan 1970 00:00:00 GMT");
223
224            oHTTP.send(null);
225        } else {
226            if (fncError)
227                fncError();
228        }
229    }
230
231    return function(strURL, fncCallback, fncError, aRange) {
232
233        if (aRange) {
234            getHead(
235                    strURL,
236                    function(oHTTP) {
237                        var iLength = parseInt(oHTTP.getResponseHeader("Content-Length"), 10);
238                        var strAcceptRanges = oHTTP.getResponseHeader("Accept-Ranges");
239
240                        var iStart, iEnd;
241                        iStart = aRange[0];
242                        if (aRange[0] < 0)
243                            iStart += iLength;
244                        iEnd = iStart + aRange[1] - 1;
245
246                        sendRequest(strURL, fncCallback, fncError, [iStart, iEnd], (strAcceptRanges == "bytes"), iLength);
247                    }
248            );
249
250        } else {
251            sendRequest(strURL, fncCallback, fncError);
252        }
253    }
254
255}());
256
257/*
258 document.write(
259 "<script type='text/vbscript'>\r\n"
260 + "Function IEBinary_getByteAt(strBinary, iOffset)\r\n"
261 + "	IEBinary_getByteAt = AscB(MidB(strBinary,iOffset+1,1))\r\n"
262 + "End Function\r\n"
263 + "Function IEBinary_getLength(strBinary)\r\n"
264 + "	IEBinary_getLength = LenB(strBinary)\r\n"
265 + "End Function\r\n"
266 + "</script>\r\n"
267 );
268 */
269
270document.write(
271        "<script type='text/vbscript'>\r\n"
272        + "Function IEBinary_getByteAt(strBinary, iOffset)\r\n"
273        + "	IEBinary_getByteAt = AscB(MidB(strBinary, iOffset + 1, 1))\r\n"
274        + "End Function\r\n"
275        + "Function IEBinary_getBytesAt(strBinary, iOffset, iLength)\r\n"
276        + "  Dim aBytes()\r\n"
277        + "  ReDim aBytes(iLength - 1)\r\n"
278        + "  For i = 0 To iLength - 1\r\n"
279        + "   aBytes(i) = IEBinary_getByteAt(strBinary, iOffset + i)\r\n"
280        + "  Next\r\n"
281        + "  IEBinary_getBytesAt = aBytes\r\n"
282        + "End Function\r\n"
283        + "Function IEBinary_getLength(strBinary)\r\n"
284        + "	IEBinary_getLength = LenB(strBinary)\r\n"
285        + "End Function\r\n"
286        + "</script>\r\n"
287        );