Merge "BrotliDecompressionSource: don't bail out too early" into main

src/libutil/compression.cc

@@ -163,12 +163,15 @@ struct BrotliDecompressionSource : Source
         uint8_t * out = (uint8_t *) data;
         const auto * begin = out;
 
-        try {
         while (len && !BrotliDecoderIsFinished(state.get())) {
             checkInterrupt();
 
             while (avail_in == 0) {
+                try {
                     avail_in = inner->read(buf.get(), BUF_SIZE);
+                } catch (EndOfFile &) {
+                    break;
+                }
                 next_in = (const uint8_t *) buf.get();
             }
 
@@ -179,8 +182,6 @@ struct BrotliDecompressionSource : Source
                 throw CompressionError("error while decompressing brotli file");
             }
         }
-        } catch (EndOfFile &) {
-        }
 
         if (begin != out) {
             return out - begin;

tests/unit/libutil/compression.cc

@@ -66,6 +66,16 @@ namespace nix {
         ASSERT_THROW(decompress(method, str), CompressionError);
     }
 
+    TEST(decompress, veryLongBrotli) {
+        auto method = "br";
+        auto str = std::string(65536, 'a');
+        auto o = decompress(method, compress(method, str));
+
+        // This is just to not print 64k of "a" for most failures
+        ASSERT_EQ(o.length(), str.length());
+        ASSERT_EQ(o, str);
+    }
+
     /* ----------------------------------------------------------------------------
      * compression sinks
      * --------------------------------------------------------------------------*/