Sakurai/pdf.js
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

parse startxref

Browse Source
This commit is contained in:
Andreas Gal 2011-05-06 01:16:09 -07:00
parent b860bc8d60
commit 16bc5f6fe3
1 changed files with 53 additions and 25 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

78
pdf.js
View File

@ -27,6 +27,9 @@ var Stream = (function() {
}
constructor.prototype = {
get length() {
return this.bytes.length;
},
reset: function() {
this.pos = 0;
},
@ -39,7 +42,7 @@ var Stream = (function() {
getChar: function() {
var ch = this.lookChar();
this.pos++;
return ch;
return String.fromCharCode(ch);
},
putBack: function() {
this.pos--;
@ -47,9 +50,26 @@ var Stream = (function() {
skipChar: function() {
this.pos++;
},
moveStart: function(delta) {
this.bytes = Uint8Array(arrayBuffer, delta);
this.pos -= delta;
skip: function(n) {
this.pos += n;
},
moveStart: function() {
this.bytes = Uint8Array(bytes, pos);
this.pos = 0;
},
find: function(str, limit, backwards) {
var length = this.bytes.length;
var pos = this.pos;
var str = "";
if (pos + limit > length)
limit = length - pos;
for (var n = 0; n < limit; ++n)
str += this.getChar();
var index = backwards ? str.lastIndexOf(str) : str.indexOf(str);
if (index == -1)
return false; /* not found */
this.pos += index;
return true; /* found */
}
};
@ -598,41 +618,49 @@ var PDFDoc = (function () {
if (linearization.length != length)
linearization = false;
}
// shadow the prototype getter
// shadow the prototype getter with a data property
return this.linearization = linearization;
},
get startXRef() {
var startXRef;
var startXRef = 0;
var linearization = this.linearization;
if (linearization) {
// TODO
// Find end of first obj.
stream.reset();
if (stream.find("endobj", 1024))
startXRef = stream.pos + 6;
} else {
// TODO
// Find startxref at the end of the file.
var start = stream.length - 1024;
if (start < 0)
start = 0;
stream.pos = start;
if (stream.find("startxref", 1024, true)) {
stream.skip(9);
var ch;
while ((ch = stream.getChar()) == " " || ch == "\t")
;
var str = "";
while ((ch - "0") <= 9) {
str += ch;
ch = stream.getChar();
}
startXRef = parseNumber(str);
if (isNaN(startXRef))
startXRef = 0;
}
}
// shadow the prototype getter
// shadow the prototype getter with a data property
return this.startXRef = startXRef;
},
// Find the header, remove leading garbage and setup the stream
// starting from the header.
checkHeader: function(stream) {
const headerSearchSize = 1024;
stream.reset();
var skip = 0;
var header = "%PDF-";
while (skip < headerSearchSize) {
stream.setPos(skip);
for (var i = 0; i < header.length; ++i) {
if (stream.getChar() != header.charCodeAt(i))
break;
}
if (stream.find("%PDF-", 1024)) {
// Found the header, trim off any garbage before it.
if (i == header.length) {
stream.moveStart(skip);
return;
}
stream.moveStart();
return;
}
// May not be a PDF file, continue anyway.