From b8bb68066047d1a3a451deeeeba143676ea6eb3e Mon Sep 17 00:00:00 2001
From: Shrek <togo33937@gmail.com>
Date: Thu, 9 Jul 2020 10:49:07 +0800
Subject: [PATCH] Modify the header to conform to ogg format, but can not play
 Ogg if the file is partially incomplete

---
 .../exoplayer2/extractor/ogg/OggPacket.java   | 11 ++++++--
 .../extractor/ogg/OggPageHeader.java          |  4 +++
 .../extractor/ogg/OggReadCheckUtil.java       | 28 +++++++++++++++++++
 3 files changed, 40 insertions(+), 3 deletions(-)
 create mode 100644 library/extractor/src/main/java/com/google/android/exoplayer2/extractor/ogg/OggReadCheckUtil.java

diff --git a/library/extractor/src/main/java/com/google/android/exoplayer2/extractor/ogg/OggPacket.java b/library/extractor/src/main/java/com/google/android/exoplayer2/extractor/ogg/OggPacket.java
index 07724cc33c0..390732ed2c2 100644
--- a/library/extractor/src/main/java/com/google/android/exoplayer2/extractor/ogg/OggPacket.java
+++ b/library/extractor/src/main/java/com/google/android/exoplayer2/extractor/ogg/OggPacket.java
@@ -75,14 +75,14 @@ public boolean populate(ExtractorInput input) throws IOException {
         if ((pageHeader.type & 0x01) == 0x01 && packetArray.limit() == 0) {
           // After seeking, the first packet may be the remainder
           // part of a continued packet which has to be discarded.
-          bytesToSkip += calculatePacketSize(segmentIndex);
+          bytesToSkip += calculatePacketSize(segmentIndex, input);
           segmentIndex += segmentCount;
         }
         input.skipFully(bytesToSkip);
         currentSegmentIndex = segmentIndex;
       }
 
-      int size = calculatePacketSize(currentSegmentIndex);
+      int size = calculatePacketSize(currentSegmentIndex, input);
       int segmentIndex = currentSegmentIndex + segmentCount;
       if (size > 0) {
         if (packetArray.capacity() < packetArray.limit() + size) {
@@ -137,7 +137,7 @@ public void trimPayload() {
    * @param startSegmentIndex the index of the first segment of the packet.
    * @return Size of the packet.
    */
-  private int calculatePacketSize(int startSegmentIndex) {
+  private int calculatePacketSize(int startSegmentIndex, ExtractorInput input) {
     segmentCount = 0;
     int size = 0;
     while (startSegmentIndex + segmentCount < pageHeader.pageSegmentCount) {
@@ -148,6 +148,11 @@ private int calculatePacketSize(int startSegmentIndex) {
         break;
       }
     }
+
+    if (OggReadCheckUtil.checkReadLengthValidity(input, size)) {
+      size = OggReadCheckUtil.fixFileReadLength(input);
+    }
+
     return size;
   }
 
diff --git a/library/extractor/src/main/java/com/google/android/exoplayer2/extractor/ogg/OggPageHeader.java b/library/extractor/src/main/java/com/google/android/exoplayer2/extractor/ogg/OggPageHeader.java
index 853347ee181..a179ab20bf0 100644
--- a/library/extractor/src/main/java/com/google/android/exoplayer2/extractor/ogg/OggPageHeader.java
+++ b/library/extractor/src/main/java/com/google/android/exoplayer2/extractor/ogg/OggPageHeader.java
@@ -163,6 +163,10 @@ public boolean populate(ExtractorInput input, boolean quiet) throws IOException
       bodySize += laces[i];
     }
 
+    if (OggReadCheckUtil.checkReadLengthValidity(input, bodySize)) {
+      bodySize = OggReadCheckUtil.fixFileReadLength(input);
+    }
+
     return true;
   }
 
diff --git a/library/extractor/src/main/java/com/google/android/exoplayer2/extractor/ogg/OggReadCheckUtil.java b/library/extractor/src/main/java/com/google/android/exoplayer2/extractor/ogg/OggReadCheckUtil.java
new file mode 100644
index 00000000000..7ef2af279d3
--- /dev/null
+++ b/library/extractor/src/main/java/com/google/android/exoplayer2/extractor/ogg/OggReadCheckUtil.java
@@ -0,0 +1,28 @@
+package com.google.android.exoplayer2.extractor.ogg;
+
+import com.google.android.exoplayer2.extractor.ExtractorInput;
+
+/**
+ * Ogg File read verification tool
+ */
+class OggReadCheckUtil {
+
+  /**
+   * Verify that the length of the read exceeds the file length
+   * @param input {@link ExtractorInput}
+   * @param readLength read length
+   * @return true The read length is greater than the file length
+   */
+  public static boolean checkReadLengthValidity(ExtractorInput input, int readLength) {
+    return input.getPeekPosition() + readLength > input.getLength() ;
+  }
+
+  /**
+   * Fix read length
+   * @param input {@link ExtractorInput}
+   * @return Length of read after fixed
+   */
+  public static int fixFileReadLength(ExtractorInput input) {
+    return (int) (input.getLength() - input.getPeekPosition());
+  }
+}