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cleanup utf8

This commit is contained in:
Dmitry Shirokov 2013-08-16 14:54:08 +10:00
parent eca1530753
commit 9c43af4fc8
1 changed files with 14 additions and 13 deletions
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27
encoding/utf8.js
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@ -14,7 +14,6 @@ module.exports = function() {
numValid = 0, numValid = 0,
numInvalid = 0, numInvalid = 0,
input = det.fRawInput, input = det.fRawInput,
i,
trailBytes = 0, trailBytes = 0,
confidence; confidence;
@ -24,11 +23,11 @@ module.exports = function() {
} }
// Scan for multi-byte sequences // Scan for multi-byte sequences
for (i=0; i<det.fRawLength; i++) { for (var i = 0; i < det.fRawLength; i++) {
var b = input[i]; var b = input[i];
if ((b & 0x80) == 0) { if ((b & 0x80) == 0)
continue; // ASCII continue; // ASCII
}
// Hi bit on char found. Figure out how long the sequence should be // Hi bit on char found. Figure out how long the sequence should be
if ((b & 0x0e0) == 0x0c0) { if ((b & 0x0e0) == 0x0c0) {
@ -66,21 +65,23 @@ module.exports = function() {
// Cook up some sort of confidence score, based on presense of a BOM // Cook up some sort of confidence score, based on presense of a BOM
// and the existence of valid and/or invalid multi-byte sequences. // and the existence of valid and/or invalid multi-byte sequences.
confidence = 0; confidence = 0;
if (hasBOM && numInvalid == 0) { if (hasBOM && numInvalid == 0)
confidence = 100; confidence = 100;
} else if (hasBOM && numValid > numInvalid * 10) { else if (hasBOM && numValid > numInvalid * 10)
confidence = 80; confidence = 80;
} else if (numValid > 3 && numInvalid == 0) { else if (numValid > 3 && numInvalid == 0)
confidence = 100; confidence = 100;
} else if (numValid > 0 && numInvalid == 0) { else if (numValid > 0 && numInvalid == 0)
confidence = 80; confidence = 80;
} else if (numValid == 0 && numInvalid == 0) { else if (numValid == 0 && numInvalid == 0)
// Plain ASCII. // Plain ASCII.
confidence = 10; confidence = 10;
} else if (numValid > numInvalid * 10) { else if (numValid > numInvalid * 10)
// Probably corruput utf-8 data. Valid sequences aren't likely by chance. // Probably corruput utf-8 data. Valid sequences aren't likely by chance.
confidence = 25; confidence = 25;
} else
return confidence == 0 ? null : new Match(det, this, confidence); return null
return new Match(det, this, confidence);
}; };
}; };