1 files changed, 90 insertions, 0 deletions
diff --git a/core/src/main/native/spark_compress_lzf_LZF.c b/core/src/main/native/spark_compress_lzf_LZF.c
new file mode 100644
index 0000000000..c2a59def3e
--- /dev/null
+++ b/core/src/main/native/spark_compress_lzf_LZF.c
@@ -0,0 +1,90 @@
+#include "spark_compress_lzf_LZF.h"
+#include <lzf.h>
+
+
+/* Helper function to throw an exception */
+static void throwException(JNIEnv *env, const char* className) {
+  jclass cls = (*env)->FindClass(env, className);
+  if (cls != 0) /* If cls is null, an exception was already thrown */
+    (*env)->ThrowNew(env, cls, "");
+}
+
+
+/* 
+ * Since LZF.compress() and LZF.decompress() have the same signatures
+ * and differ only in which lzf_ function they call, implement both in a
+ * single function and pass it a pointer to the correct lzf_ function.
+ */
+static jint callCompressionFunction
+  (unsigned int (*func)(const void *const, unsigned int, void *, unsigned int),
+   JNIEnv *env, jclass cls, jbyteArray inArray, jint inOff, jint inLen,
+   jbyteArray outArray, jint outOff, jint outLen)
+{
+  jint inCap;
+  jint outCap;
+  jbyte *inData = 0;
+  jbyte *outData = 0;
+  jint ret;
+  jint s;
+
+  if (!inArray || !outArray) {
+    throwException(env, "java/lang/NullPointerException");
+    goto cleanup;
+  }
+
+  inCap = (*env)->GetArrayLength(env, inArray);
+  outCap = (*env)->GetArrayLength(env, outArray);
+
+  // Check if any of the offset/length pairs is invalid; we do this by OR'ing
+  // things we don't want to be negative and seeing if the result is negative
+  s = inOff | inLen | (inOff + inLen) | (inCap - (inOff + inLen)) |
+      outOff | outLen | (outOff + outLen) | (outCap - (outOff + outLen));
+  if (s < 0) {
+    throwException(env, "java/lang/IndexOutOfBoundsException");
+    goto cleanup;
+  }
+
+  inData = (*env)->GetPrimitiveArrayCritical(env, inArray, 0);
+  outData = (*env)->GetPrimitiveArrayCritical(env, outArray, 0);
+
+  if (!inData || !outData) {
+    // Out of memory - JVM will throw OutOfMemoryError
+    goto cleanup;
+  }
+  
+  ret = func(inData + inOff, inLen, outData + outOff, outLen);
+
+cleanup:
+  if (inData)
+    (*env)->ReleasePrimitiveArrayCritical(env, inArray, inData, 0);
+  if (outData)
+    (*env)->ReleasePrimitiveArrayCritical(env, outArray, outData, 0);
+  
+  return ret;
+}
+
+/*
+ * Class:     spark_compress_lzf_LZF
+ * Method:    compress
+ * Signature: ([B[B)I
+ */
+JNIEXPORT jint JNICALL Java_spark_compress_lzf_LZF_compress
+  (JNIEnv *env, jclass cls, jbyteArray inArray, jint inOff, jint inLen,
+   jbyteArray outArray, jint outOff, jint outLen)
+{
+  return callCompressionFunction(lzf_compress, env, cls, 
+      inArray, inOff, inLen, outArray,outOff, outLen);
+}
+
+/*
+ * Class:     spark_compress_lzf_LZF
+ * Method:    decompress
+ * Signature: ([B[B)I
+ */
+JNIEXPORT jint JNICALL Java_spark_compress_lzf_LZF_decompress
+  (JNIEnv *env, jclass cls, jbyteArray inArray, jint inOff, jint inLen,
+   jbyteArray outArray, jint outOff, jint outLen)
+{
+  return callCompressionFunction(lzf_decompress, env, cls, 
+      inArray, inOff, inLen, outArray,outOff, outLen);
+}