/
IsProbablyUtf8.kt
44 lines (42 loc) · 1.35 KB
/
IsProbablyUtf8.kt
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/*
* Copyright (C) 2015 Square, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package okhttp3.logging.internal
import java.io.EOFException
import okio.Buffer
/**
* Returns true if the body in question probably contains human readable text. Uses a small
* sample of code points to detect unicode control characters commonly used in binary file
* signatures.
*/
fun Buffer.isProbablyUtf8(): Boolean {
try {
val prefix = Buffer()
val byteCount = size.coerceAtMost(64)
copyTo(prefix, 0, byteCount)
for (i in 0 until 16) {
if (prefix.exhausted()) {
break
}
val codePoint = prefix.readUtf8CodePoint()
if (Character.isISOControl(codePoint) && !Character.isWhitespace(codePoint)) {
return false
}
}
return true
} catch (_: EOFException) {
return false // Truncated UTF-8 sequence.
}
}