add FlvChecker

src/main/kotlin/cn/tursom/core/FlvChecker.kt

@@ -0,0 +1,157 @@
+package cn.tursom.core
+
+import java.io.*
+
+/**
+ * 原理 https://www.cnblogs.com/lidabo/p/9018548.html
+ */
+class FlvChecker {
+  // 用于缓冲
+  private val buffer = ByteArray(1024 * 1024 * 16)
+
+  /**
+   * 从头部开始Check, 重新锚定时间戳, 将最后一帧(不管是否完整)去掉
+   *
+   * @param path
+   * @throws IOException
+   */
+// 用于统计时间戳
+  private val lastTimestampRead = intArrayOf(-1, -1)
+  private val lastTimestampWrite = intArrayOf(-1, -1)
+
+  /**
+   * 从头部开始Check, 重新锚定时间戳, 将最后一帧(不管是否完整)去掉
+   */
+  fun check(raf: InputStream, rafNew: OutputStream) { // 用于排除无效尾巴帧
+    // 复制头部
+    raf.read(buffer, 0, 9)
+    rafNew.write(buffer, 0, 9)
+    var currentLength = 9L
+    //var latsValidLength = currentLength
+    try {
+      var remain = 40
+      var timestamp = 0
+      while (true) { // && remain>=0
+        remain--
+        // 读取前一个tag size
+        readBytesToInt(raf, 4)
+        // Logger.print("前一个长度为：" + predataSize);
+        // 读取tag
+        // tag 类型
+        val tagType = raf.read()
+        if (tagType == 8 || tagType == 9) {
+          rafNew.write(buffer, 0, 4)
+          rafNew.write(tagType)
+          // tag data size 3个字节。表示tag data的长度。从streamd id 后算起。
+          val dataSize = readBytesToInt(raf, 3)
+          rafNew.write(buffer, 0, 3)
+          // Logger.print(" ,当前tag data 长度为：" + dataSize);
+          // 时间戳 3
+          timestamp = readBytesToInt(raf, 3)
+          val timestampEx = raf.read() shl 24
+          timestamp += timestampEx
+          dealTimestamp(rafNew, timestamp, tagType - 8)
+          raf.read(buffer, 0, 3 + dataSize)
+          rafNew.write(buffer, 0, 3 + dataSize)
+        } else if (tagType == 18) {
+          // 18 scripts
+          // 如果是scripts脚本，默认为第一个tag，此时将前一个tag Size 置零
+          //rafNew.seek(rafNew.filePointer - 4)
+          val zeroTimestamp = byteArrayOf(0, 0, 0, 0)
+          rafNew.write(zeroTimestamp)
+          rafNew.write(tagType)
+          val dataSize = readBytesToInt(raf, 3)
+          rafNew.write(buffer, 0, 3)
+          raf.read(buffer, 0, 4)
+          val zeros = byteArrayOf(0, 0, 0)
+          rafNew.write(zeros) // 时间戳 0
+          rafNew.write(0) // 时间戳扩展 0
+          raf.read(buffer, 0, 3 + dataSize)
+          rafNew.write(buffer, 0, 3 + dataSize)
+
+        } else {
+          break
+        }
+      }
+    } catch (e: Exception) {
+      e.printStackTrace()
+    }
+  }
+
+  /**
+   * 处理音/视频时间戳
+   *
+   * @param raf
+   * @param timestamp
+   * @throws IOException
+   * @return 是否忽略该tag
+   */
+  private fun dealTimestamp(raf: OutputStream, timestamp: Int, tagType: Int): Boolean {
+    // 如果是首帧
+    if (lastTimestampRead[tagType] == -1) {
+      lastTimestampWrite[tagType] = 0
+    } else if (timestamp >= lastTimestampRead[tagType]) {
+      // 如果时序正常
+      // 间隔十分巨大(1s)，那么重新开始即可
+      if (timestamp > lastTimestampRead[tagType] + 1000) {
+        lastTimestampWrite[tagType] += 10
+      } else {
+        lastTimestampWrite[tagType] = timestamp - lastTimestampRead[tagType] + lastTimestampWrite[tagType]
+      }
+    } else {
+      // 如果出现倒序时间戳
+      // 如果间隔不大，那么如实反馈
+      if (lastTimestampRead[tagType] - timestamp < 5 * 1000) {
+        var tmp = timestamp - lastTimestampRead[tagType] + lastTimestampWrite[tagType]
+        tmp = if (tmp > 0) tmp else 1
+        lastTimestampWrite[tagType] = tmp
+      } else { // 间隔十分巨大，那么重新开始即可
+        lastTimestampWrite[tagType] += 10
+      }
+    }
+    lastTimestampRead[tagType] = timestamp
+    // 低于0xffffff部分
+    val lowCurrentTime = lastTimestampWrite[tagType] and 0xffffff
+    raf.write(int2Bytes(lowCurrentTime), 1, 3)
+    // 高于0xffffff部分
+    val highCurrentTime = lastTimestampWrite[tagType] shr 24
+    raf.write(highCurrentTime)
+    return true
+  }
+
+  /**
+   * @param raf
+   * @param byteLength
+   * @return
+   * @throws IOException
+   */
+  private fun readBytesToInt(raf: InputStream, byteLength: Int): Int {
+    raf.read(buffer, 0, byteLength)
+    return bytes2Int(buffer, byteLength)
+  }
+
+  private fun int2Bytes(value: Int): ByteArray {
+    val byteRet = ByteArray(4)
+    for (i in 0..3) {
+      byteRet[3 - i] = (value shr 8 * i and 0xff).toByte()
+    }
+    return byteRet
+  }
+
+  private fun bytes2Int(bytes: ByteArray, byteLength: Int): Int {
+    var result = 0
+    for (i in 0 until byteLength) {
+      result = result or (bytes[byteLength - 1 - i].toInt() and 0xff shl i * 8)
+      // System.out.printf("%x ",(bytes[i] & 0xff));
+    }
+    return result
+  }
+}
+
+fun main() {
+  val checker = FlvChecker()
+  checker.check(
+    File("test.flv").inputStream().buffered(),
+    File("1.flv").outputStream().buffered()
+  )
+}

src/main/kotlin/cn/tursom/core/buffer/ByteBuffer.kt

@@ -2,6 +2,7 @@ package cn.tursom.core.buffer
 
 import cn.tursom.core.forEachIndex
 import java.io.Closeable
+import java.io.IOException
 import java.io.InputStream
 import java.io.OutputStream
 import kotlin.math.min
@@ -202,6 +203,7 @@ interface ByteBuffer : Closeable {
   fun put(inputStream: InputStream) {
     if (hasArray) {
       val read = inputStream.read(array, writeOffset, writeable)
+      if (read < 0) throw  IOException("stream closed")
       writePosition += read
     } else {
       val buffer = ByteArray(10 * 1024)
@@ -210,6 +212,19 @@ interface ByteBuffer : Closeable {
     }
   }
 
+  fun put(inputStream: InputStream, size: Int) {
+    assert(size <= writeable)
+    if (hasArray) {
+      val read = inputStream.read(array, writeOffset, size)
+      if (read < 0) throw  IOException("stream closed")
+      writePosition += read
+    } else {
+      val buffer = ByteArray(size)
+      val read = inputStream.read(buffer)
+      put(buffer, 0, read)
+    }
+  }
+
   fun putByte(byte: Byte): Unit = put(byte)
   fun putChar(char: Char): Unit = put(char)
   fun putShort(short: Short): Unit = put(short)
@@ -256,4 +271,5 @@ interface ByteBuffer : Closeable {
     readPosition += size
     return size
   }
-}
+}
+