Work for upstream PR 175.

contrib/hiddenalpha-buildEnv-one/README.txt

@@ -18,7 +18,7 @@ Initially written for jssc 2.9.5.
       -Wno-error=sign-compare \
       -Wno-error=variadic-macros \
       -Wno-long-long" \
-  && PKGSTOADD="curl git g++ maven gdb patch zip unzip" \
+  && PKGSTOADD="curl git g++ make cmake maven gdb patch zip unzip" \
   && SUDO=sudo \
   && JSSC_CPP=src/main/cpp/_nix_based/jssc.cpp \
   && LIBJSSC_SO=src/main/resources-precompiled/natives/linux_64/libjssc.so \
@@ -78,6 +78,12 @@ Initially written for jssc 2.9.5.
   && (cd target && sha256sum -b jssc-*.jar > "${SUMFILE:?}") \
 
 
+
+## Use maven
+
+  && mvn -Px86_64 ...
+
+
 ## gdb
 
 For debugging, adjust CFLAGS to include debugger info and re-compile.

src/main/cpp/windows/jssc.cpp

@@ -276,17 +276,33 @@ JNIEXPORT jbyteArray JNICALL Java_jssc_SerialNativeInterface_readBytes
     HANDLE hComm = (HANDLE)portHandle;
     DWORD lpNumberOfBytesTransferred;
     DWORD lpNumberOfBytesRead;
+    jbyteArray returnArray = NULL;
     jbyte *lpBuffer = NULL;
+    OVERLAPPED *overlapped = NULL;
 
-    jbyteArray returnArray = env->NewByteArray(byteCount);
+    if( byteCount < 0 ){
+        /* Negative byteCount makes no sense -> Report to caller by exception. */
+        char exMsg[48]; exMsg[0] = '\0';
+        snprintf(exMsg, sizeof exMsg, "byteCount %d", byteCount);
+        jclass exClz = env->FindClass("java/lang/IllegalArgumentException");
+        if( exClz != NULL ) env->ThrowNew(exClz, exMsg);
+        goto Finally;
+    }
+
+    returnArray = env->NewByteArray(byteCount);
+    if( returnArray == NULL ) goto Finally;
 
     lpBuffer = (jbyte *)malloc(byteCount * sizeof(jbyte));
     if(lpBuffer == NULL){
-        // return an empty array
-        return returnArray;
+        /* Whops. Not enough memory. Let caller know through exception. */
+        char exMsg[32]; exMsg[0] = '\0';
+        snprintf(exMsg, sizeof exMsg, "malloc(%d)", byteCount);
+        jclass exClz = env->FindClass("java/lang/OutOfMemoryError");
+        if( exClz != NULL ) env->ThrowNew(exClz, exMsg);
+        goto Finally;
     }
 
-    OVERLAPPED *overlapped = new OVERLAPPED();
+    overlapped = new OVERLAPPED();
     overlapped->hEvent = CreateEventA(NULL, true, false, NULL);
     if(ReadFile(hComm, lpBuffer, (DWORD)byteCount, &lpNumberOfBytesRead, overlapped)){
         env->SetByteArrayRegion(returnArray, 0, byteCount, lpBuffer);
@@ -302,9 +318,12 @@ JNIEXPORT jbyteArray JNICALL Java_jssc_SerialNativeInterface_readBytes
         jclass exClz = env->FindClass("java/lang/IllegalArgumentException");
         if( exClz != NULL ) env->ThrowNew(exClz, "EBADF");
     }
-    CloseHandle(overlapped->hEvent);
-    delete overlapped;
-    free(lpBuffer);
+Finally:
+    if( overlapped != NULL ){
+        CloseHandle(overlapped->hEvent);
+        delete overlapped;
+    }
+    if( lpBuffer != NULL ) free(lpBuffer);
     return returnArray;
 }
 

src/test/java/jssc/SerialNativeInterfaceTest.java

@@ -94,4 +94,34 @@ public void throwsNpeIfPassedBufferIsNull() throws Exception {
         new SerialNativeInterface().writeBytes(1, null);
     }
 
+    @Test
+    public void throwsIaeIfCountNegative() throws Exception {
+        SerialNativeInterface testTarget = new SerialNativeInterface();
+        byte[] ret;
+        try{
+            ret = testTarget.readBytes(0, -42);
+            fail("Where's the exception?");
+        }catch( IllegalArgumentException ex ){
+            assertTrue(ex.getMessage().contains("-42"));
+        }
+    }
+
+    @Test
+    @org.junit.Ignore("This test only makes sense if it is run in a situation"
+        +" where large memory allocations WILL fail (for example you could use"
+        +" a virtual machine with low memory available). Because on regular"
+        +" machines allocating 2GiB of RAM is not a problem at all and so the"
+        +" test run will just happily wait infinitely for those 2GiB to arrive"
+        +" at the stdin fd. Feel free to remove this test if you think it"
+        +" doesn't make sense to have it here.")
+    public void throwsOOMExIfRequestTooLarge() throws Exception {
+        SerialNativeInterface testTarget = new SerialNativeInterface();
+        try{
+            byte[] ret = testTarget.readBytes(0, Integer.MAX_VALUE);
+            fail("Where's the exception?");
+        }catch( OutOfMemoryError ex ){
+            assertTrue(ex.getMessage().contains(String.valueOf(Integer.MAX_VALUE)));
+        }
+    }
+
 }