commit 0b9f7de6fc0f806ae414a6712449f7ca6e56bd0f
author Dichen Zhang <dichenzhang@google.com> Fri Nov 18 06:52:46 2022 +0000
committer Dichen Zhang <dichenzhang@google.com> Mon Nov 21 18:39:07 2022 +0000
tree 7a3170f7e09289d1ee7ff563f92c7a09dee55db1
parent d4ebf5423ae43a7b30ae60359acf028a93cc1eac

libjpegrecoverymap: a few fixes

1. introduce maxLength parameter in compressed data structure that holds max available buffer size, and buffer boundary checks should rely on this parameter
2. make recovery map compress quality a static configuration instead of using a magic number

Change-Id: I4af25931ab905c0d524cfa02c6057e9cf128b5ca
Test: build
Bug: b/252835416

libs/jpegrecoverymap/recoverymap.cpp

diff --git a/libs/jpegrecoverymap/recoverymap.cpp b/libs/jpegrecoverymap/recoverymap.cpp
index 64021b7..ad41839 100644
--- a/libs/jpegrecoverymap/recoverymap.cpp
+++ b/libs/jpegrecoverymap/recoverymap.cpp
@@ -43,6 +43,8 @@
 
 // Map is quarter res / sixteenth size
 static const size_t kMapDimensionScaleFactor = 4;
+// JPEG compress quality (0 ~ 100) for recovery map
+static const int kMapCompressQuality = 85;
 
 // TODO: fill in st2086 metadata
 static const st2086_metadata kSt2086Metadata = {
@@ -77,7 +79,7 @@
  * @return status of succeed or error code.
  */
 status_t Write(jr_compressed_ptr destination, const void* source, size_t length, int &position) {
-  if (position + length > destination->length) {
+  if (position + length > destination->maxLength) {
     return ERROR_JPEGR_BUFFER_TOO_SMALL;
   }
 
@@ -121,8 +123,8 @@
   map_data.reset(reinterpret_cast<uint8_t*>(map.data));
 
   jpegr_compressed_struct compressed_map;
-  std::unique_ptr<uint8_t[]> compressed_map_data =
-      std::make_unique<uint8_t[]>(map.width * map.height);
+  compressed_map.maxLength = map.width * map.height;
+  unique_ptr<uint8_t[]> compressed_map_data = make_unique<uint8_t[]>(compressed_map.maxLength);
   compressed_map.data = compressed_map_data.get();
   JPEGR_CHECK(compressRecoveryMap(&map, &compressed_map));
 
@@ -173,8 +175,8 @@
   map_data.reset(reinterpret_cast<uint8_t*>(map.data));
 
   jpegr_compressed_struct compressed_map;
-  std::unique_ptr<uint8_t[]> compressed_map_data =
-      std::make_unique<uint8_t[]>(map.width * map.height);
+  compressed_map.maxLength = map.width * map.height;
+  unique_ptr<uint8_t[]> compressed_map_data = make_unique<uint8_t[]>(compressed_map.maxLength);
   compressed_map.data = compressed_map_data.get();
   JPEGR_CHECK(compressRecoveryMap(&map, &compressed_map));
 
@@ -222,8 +224,8 @@
   map_data.reset(reinterpret_cast<uint8_t*>(map.data));
 
   jpegr_compressed_struct compressed_map;
-  std::unique_ptr<uint8_t[]> compressed_map_data =
-      std::make_unique<uint8_t[]>(map.width * map.height);
+  compressed_map.maxLength = map.width * map.height;
+  unique_ptr<uint8_t[]> compressed_map_data = make_unique<uint8_t[]>(compressed_map.maxLength);
   compressed_map.data = compressed_map_data.get();
   JPEGR_CHECK(compressRecoveryMap(&map, &compressed_map));
 
@@ -289,13 +291,17 @@
 
   // TODO: should we have ICC data for the map?
   JpegEncoder jpeg_encoder;
-  if (!jpeg_encoder.compressImage(uncompressed_recovery_map->data, uncompressed_recovery_map->width,
-                                  uncompressed_recovery_map->height, 85, nullptr, 0,
+  if (!jpeg_encoder.compressImage(uncompressed_recovery_map->data,
+                                  uncompressed_recovery_map->width,
+                                  uncompressed_recovery_map->height,
+                                  kMapCompressQuality,
+                                  nullptr,
+                                  0,
                                   true /* isSingleChannel */)) {
     return ERROR_JPEGR_ENCODE_ERROR;
   }
 
-  if (dest->length < jpeg_encoder.getCompressedImageSize()) {
+  if (dest->maxLength < jpeg_encoder.getCompressedImageSize()) {
     return ERROR_JPEGR_BUFFER_TOO_SMALL;
   }