Move project to `ch.jodersky` and upgrade sbt-jni

9 files changed, 472 insertions, 470 deletions

diff --git a/flow-native/build.sbt b/flow-native/build.sbt
index b6b39a0..1f5720e 100644
--- a/flow-native/build.sbt
+++ b/flow-native/build.sbt
@@ -4,6 +4,7 @@ FlowBuild.commonSettings
 
 enablePlugins(JniNative)
 
-sourceDirectory in nativeCompile in Compile := sourceDirectory.value
+sourceDirectory in nativeCompile := sourceDirectory.value
 
-nativeLibraryPath in Compile := "com/github/jodersky/flow"
+// uncomment below to use library in lib_native instead
+//enableNativeCompilation in Compile := false
diff --git a/flow-native/src/.gitignore b/flow-native/src/.gitignore
index e259f31..1785c46 100644
--- a/flow-native/src/.gitignore
+++ b/flow-native/src/.gitignore
@@ -1,8 +1,8 @@
 # CMake
-CMakeFiles/
-CMakeCache.txt
-cmake_install.cmake
-Makefile
+/CMakeFiles/
+/CMakeCache.txt
+/cmake_install.cmake
+/Makefile
 
 # Binary files
 *.o
diff --git a/flow-native/src/CMakeLists.txt b/flow-native/src/CMakeLists.txt
index 7f6cbd7..8be2fab 100644
--- a/flow-native/src/CMakeLists.txt
+++ b/flow-native/src/CMakeLists.txt
@@ -1,23 +1,24 @@
-cmake_minimum_required(VERSION 2.6)
+################################################################
+# A minimal CMake file that is compatible with sbt-jni         #
+#                                                              #
+# All settings required by sbt-jni have been marked so, please #
+# add/modify/remove settings to build your specific library.   #
+################################################################
+
+cmake_minimum_required(VERSION 2.8.0)
 
 # Define project and related variables
+# (required by sbt-jni) please use semantic versioning
 #
 project (flow)
+set(PROJECT_VERSION_MAJOR 4)
+set(PROJECT_VERSION_MINOR 0)
+set(PROJECT_VERSION_PATCH 0)
 
-# Set versions and library name
-# Note: major version will be appended to library name
-#
-set (VERSION_MAJOR 3)
-set (VERSION_MINOR 0)
-set (VERSION_PATCH 1)
-set (LIB_NAME flow${VERSION_MAJOR})
-
-# Command-line options
-#
-# required by sbt-jni to install binaries to correct places
-set (LIB_INSTALL_DIR lib CACHE PATH "Path in which to install libraries (Autoconf equivalent to --libdir).")
-# required by sbt-jni to disable versioned libraries
-set (ENABLE_VERSIONED_LIB ON CACHE BOOLEAN "Generate versioned library files and symlinks.")
+set(CMAKE_C_FLAGS "-std=c99")
+add_definitions(-Wall)
+add_definitions(-Wextra)
+add_definitions(-pedantic)
 
 # Setup JNI
 find_package(JNI REQUIRED)
@@ -26,20 +27,19 @@ if (JNI_FOUND)
 endif()
 
 # Include directories
+include_directories(.)
 include_directories(include)
 include_directories(${JNI_INCLUDE_DIRS})
 
-# Setup main shared library
-# Note: major version is appended to library name
-add_library(${LIB_NAME} SHARED flow_jni.c platform/posix/flow.c)
-if (ENABLE_VERSIONED_LIB)
-   set_target_properties(
-	${LIB_NAME}
-	PROPERTIES
-	VERSION 0.${VERSION_MINOR}.${VERSION_PATCH} # major version always 0, it is included in name
-	SOVERSION 0
-   )
-endif()
+# Sources
+file(GLOB LIB_SRC
+  "*.c"
+  "platform/posix/*.c"
+)
 
-# Installation targets
-install(TARGETS ${LIB_NAME} LIBRARY DESTINATION ${LIB_INSTALL_DIR}) 
+# Setup installation targets
+# (required by sbt-jni) major version should always be appended to library name
+#
+set (LIB_NAME ${PROJECT_NAME}${PROJECT_VERSION_MAJOR})
+add_library(${LIB_NAME} SHARED ${LIB_SRC})
+install(TARGETS ${LIB_NAME} LIBRARY DESTINATION .)
diff --git a/flow-native/src/flow_jni.c b/flow-native/src/flow_jni.c
index 8ec2aed..75bffff 100644
--- a/flow-native/src/flow_jni.c
+++ b/flow-native/src/flow_jni.c
@@ -1,169 +1,150 @@
+#include <stdint.h>
+
 #include "flow.h"
-#include "com_github_jodersky_flow_internal_NativeSerial.h"
 
+#include "ch_jodersky_flow_UnsafeSerial.h"
+#include "ch_jodersky_flow_UnsafeSerial__.h"
 
-static inline void throwException(JNIEnv* env, const char* const exception, const char * const message) {
-  (*env)->ThrowNew(env, (*env)->FindClass(env, exception), message); 
-}
+// suppress unused parameter warnings
+#define UNUSED_ARG(x) (void)(x)
 
-static inline void check(JNIEnv* env, int id) {
-  switch (id) {
-    case E_IO: throwException(env, "java/io/IOException", ""); break;
-    case E_BUSY: throwException(env, "com/github/jodersky/flow/PortInUseException", ""); break;
-    case E_ACCESS_DENIED: throwException(env, "com/github/jodersky/flow/AccessDeniedException", ""); break;
-    case E_INVALID_SETTINGS: throwException(env, "com/github/jodersky/flow/InvalidSettingsException", ""); break;
-    case E_INTERRUPT: throwException(env, "com/github/jodersky/flow/PortInterruptedException", ""); break;
-    case E_NO_PORT: throwException(env, "com/github/jodersky/flow/NoSuchPortException", ""); break;
-    default: return;
-  }
+static inline void throwException(JNIEnv* env, const char* const exception, const char * const message)
+{
+	(*env)->ThrowNew(env, (*env)->FindClass(env, exception), message);
 }
- 
 
-/*
- * Class:     com_github_jodersky_flow_internal_NativeSerial
- * Method:    open
- * Signature: (Ljava/lang/String;IIZI)J
- */
-JNIEXPORT jlong JNICALL Java_com_github_jodersky_flow_internal_NativeSerial_open
-  (JNIEnv *env, jclass clazz, jstring port_name, jint baud, jint char_size, jboolean two_stop_bits, jint parity) { 
-
-    const char *dev = (*env)->GetStringUTFChars(env, port_name, 0);
-    struct serial_config* config;
-    int r = serial_open(dev, baud, char_size, two_stop_bits, parity, &config);
-    (*env)->ReleaseStringUTFChars(env, port_name, dev);
-
-  
-    if (r < 0) {
-      check(env, r);
-      return 0;
-    }
-  
-    long jpointer = (long) config;
-    return jpointer;
+/** Check return code and throw exception in case it is non-zero. */
+static void check(JNIEnv* env, int ret)
+{
+	switch (ret) {
+	case -E_IO: throwException(env, "java/io/IOException", ""); break;
+	case -E_BUSY: throwException(env, "ch/jodersky/flow/PortInUseException", ""); break;
+	case -E_ACCESS_DENIED: throwException(env, "ch/jodersky/flow/AccessDeniedException", ""); break;
+	case -E_INVALID_SETTINGS: throwException(env, "ch/jodersky/flow/InvalidSettingsException", ""); break;
+	case -E_INTERRUPT: throwException(env, "ch/jodersky/flow/PortInterruptedException", ""); break;
+	case -E_NO_PORT: throwException(env, "ch/jodersky/flow/NoSuchPortException", ""); break;
+	default: return;
+	}
+}
 
+/** Get pointer to serial config associated to an UnsafeSerial instance. */
+static struct serial_config* get_config(JNIEnv* env, jobject unsafe_serial)
+{
+	jclass clazz = (*env)->FindClass(env, "ch/jodersky/flow/UnsafeSerial");
+	jfieldID field = (*env)->GetFieldID(env, clazz, "serialAddr", "J");
+	jlong addr = (*env)->GetLongField(env, unsafe_serial, field);
+	return (struct serial_config*) (intptr_t) addr;
 }
 
 /*
- * Class:     com_github_jodersky_flow_internal_NativeSerial
- * Method:    readDirect
- * Signature: (JLjava/nio/ByteBuffer;)I
+ * Class:     ch_jodersky_flow_UnsafeSerial__
+ * Method:    open
+ * Signature: (Ljava/lang/String;IIZI)J
  */
-JNIEXPORT jint JNICALL Java_com_github_jodersky_flow_internal_NativeSerial_readDirect
-  (JNIEnv *env, jclass clazz, jlong config, jobject buffer) {
-
-    char* local_buffer = (char*) (*env)->GetDirectBufferAddress(env, buffer);
-    if (local_buffer == NULL) {
-        throwException(env, "java/lang/IllegalArgumentException", "ByteBuffer not direct");
-        return -1;
-    }
-    jlong size = (*env)->GetDirectBufferCapacity(env, buffer);
-
-    int r = serial_read((struct serial_config*) config, local_buffer, (size_t) size);
-    if (r < 0) {
-      check(env, r);
-      return -1;
-    }
-    return r;
-
+JNIEXPORT jlong JNICALL Java_ch_jodersky_flow_UnsafeSerial_00024_open
+(JNIEnv *env, jobject instance, jstring port_name, jint baud, jint char_size, jboolean two_stop_bits, jint parity)
+{
+	UNUSED_ARG(instance);
+
+	const char *dev = (*env)->GetStringUTFChars(env, port_name, 0);
+	struct serial_config* config;
+	int r = serial_open(dev, baud, char_size, two_stop_bits, parity, &config);
+	(*env)->ReleaseStringUTFChars(env, port_name, dev);
+
+	if (r < 0) {
+		check(env, r);
+		return -E_IO;
+	}
+
+	long jpointer = (long) config;
+	return (jlong) jpointer;
 }
 
 /*
- * Class:     com_github_jodersky_flow_internal_NativeSerial
+ * Class:     ch_jodersky_flow_UnsafeSerial
  * Method:    read
- * Signature: (J[B)I
+ * Signature: (Ljava/nio/ByteBuffer;)I
  */
-JNIEXPORT jint JNICALL Java_com_github_jodersky_flow_internal_NativeSerial_read
-  (JNIEnv *env, jclass clazz, jlong config, jbyteArray buffer) {
-
-    jsize size = (*env)->GetArrayLength(env, buffer);
-    char local_buffer[size];
-    int r = serial_read((struct serial_config*) config, local_buffer, size);
-    if (r < 0) {
-      check(env, r);
-      return -1;
-    }
-
-    (*env)->SetByteArrayRegion(env, buffer, 0, r, (signed char *) local_buffer);
-    return r;
+JNIEXPORT jint JNICALL Java_ch_jodersky_flow_UnsafeSerial_read
+(JNIEnv *env, jobject instance, jobject buffer)
+{
+	char* local_buffer = (char*) (*env)->GetDirectBufferAddress(env, buffer);
+	if (local_buffer == NULL) {
+		throwException(env, "java/lang/IllegalArgumentException", "buffer is not direct");
+		return -E_IO;
+	}
+	size_t size = (size_t) (*env)->GetDirectBufferCapacity(env, buffer);
+	struct serial_config* config = get_config(env, instance);
+
+	int r = serial_read(config, local_buffer, size);
+	if (r < 0) {
+		check(env, r);
+	}
+	return r;
 
 }
 
 /*
- * Class:     com_github_jodersky_flow_internal_NativeSerial
+ * Class:     ch_jodersky_flow_UnsafeSerial
  * Method:    cancelRead
- * Signature: (J)V
+ * Signature: ()V
  */
-JNIEXPORT void JNICALL Java_com_github_jodersky_flow_internal_NativeSerial_cancelRead
-  (JNIEnv *env, jclass clazz, jlong config) {
-
-  int r = serial_cancel_read((struct serial_config*) config);
-  if (r < 0) {
-    check(env, r);
-  }
-    
+JNIEXPORT void JNICALL Java_ch_jodersky_flow_UnsafeSerial_cancelRead
+(JNIEnv *env, jobject instance)
+{
+	int r = serial_cancel_read(get_config(env, instance));
+	if (r < 0) {
+		check(env, r);
+	}
 }
 
 /*
- * Class:     com_github_jodersky_flow_internal_NativeSerial
- * Method:    writeDirect
- * Signature: (JLjava/nio/ByteBuffer;I)I
- */
-JNIEXPORT jint JNICALL Java_com_github_jodersky_flow_internal_NativeSerial_writeDirect
-  (JNIEnv *env, jclass clazz, jlong config, jobject buffer, jint size) {
-
-    char* local_buffer = (char *) (*env)->GetDirectBufferAddress(env, buffer);
-    if (local_buffer == NULL) {
-        throwException(env, "java/lang/IllegalArgumentException", "ByteBuffer not direct");
-        return -1;
-    }
-
-    int r = serial_write((struct serial_config*) config, local_buffer, (size_t) size);
-    if (r < 0) {
-      check(env, r);
-      return -1;
-    }
-    return r;
-    
-}
-
-/*
- * Class:     com_github_jodersky_flow_internal_NativeSerial
+ * Class:     ch_jodersky_flow_UnsafeSerial
  * Method:    write
- * Signature: (J[BI)I
+ * Signature: (Ljava/nio/ByteBuffer;I)I
  */
-JNIEXPORT jint JNICALL Java_com_github_jodersky_flow_internal_NativeSerial_write
-  (JNIEnv *env, jclass clazz, jlong config, jbyteArray buffer, jint size) {
-    
-    char* local_buffer = (char*) (*env)->GetByteArrayElements(env, buffer, NULL);
-    int r = serial_write((struct serial_config*) config, local_buffer, size);
-    (*env)->ReleaseByteArrayElements(env, buffer, (signed char*) local_buffer, JNI_ABORT);
-    if (r < 0) {
-      check(env, r);
-      return -1;
-    }
-    return r;
-
+JNIEXPORT jint JNICALL Java_ch_jodersky_flow_UnsafeSerial_write
+(JNIEnv *env, jobject instance, jobject buffer, jint size)
+{
+
+	char* local_buffer = (char *) (*env)->GetDirectBufferAddress(env, buffer);
+	if (local_buffer == NULL) {
+		throwException(env, "java/lang/IllegalArgumentException", "buffer is not direct");
+		return -E_IO;
+	}
+
+	int r = serial_write(get_config(env, instance), local_buffer, (size_t) size);
+	if (r < 0) {
+		check(env, r);
+		return -E_IO;
+	}
+	return r;
 }
 
 /*
- * Class:     com_github_jodersky_flow_internal_NativeSerial
+ * Class:     ch_jodersky_flow_UnsafeSerial
  * Method:    close
- * Signature: (J)V
+ * Signature: ()V
  */
-JNIEXPORT void JNICALL Java_com_github_jodersky_flow_internal_NativeSerial_close
-  (JNIEnv *env, jclass clazz, jlong config) {
-    int r = serial_close((struct serial_config*) config);
-    if (r < 0) {
-      check(env, r);
-    }
+JNIEXPORT void JNICALL Java_ch_jodersky_flow_UnsafeSerial_close
+(JNIEnv *env, jobject instance)
+{
+	int r = serial_close(get_config(env, instance));
+	if (r < 0) {
+		check(env, r);
+	}
 }
 
 /*
- * Class:     com_github_jodersky_flow_internal_NativeSerial
+ * Class:     ch_jodersky_flow_UnsafeSerial__
  * Method:    debug
  * Signature: (Z)V
  */
-JNIEXPORT void JNICALL Java_com_github_jodersky_flow_internal_NativeSerial_debug
-  (JNIEnv *env, jclass clazz, jboolean value) {
-    serial_debug((bool) value);
-}
\ No newline at end of file
+JNIEXPORT void JNICALL Java_ch_jodersky_flow_UnsafeSerial_00024_debug
+(JNIEnv *env, jobject instance, jboolean value)
+{
+	UNUSED_ARG(env);
+	UNUSED_ARG(instance);
+
+	serial_debug((bool) value);
+}
diff --git a/flow-native/src/include/ch_jodersky_flow_UnsafeSerial.h b/flow-native/src/include/ch_jodersky_flow_UnsafeSerial.h
new file mode 100644
index 0000000..f80ada0
--- /dev/null
+++ b/flow-native/src/include/ch_jodersky_flow_UnsafeSerial.h
@@ -0,0 +1,45 @@
+/* DO NOT EDIT THIS FILE - it is machine generated */
+#include <jni.h>
+/* Header for class ch_jodersky_flow_UnsafeSerial */
+
+#ifndef _Included_ch_jodersky_flow_UnsafeSerial
+#define _Included_ch_jodersky_flow_UnsafeSerial
+#ifdef __cplusplus
+extern "C" {
+#endif
+/*
+ * Class:     ch_jodersky_flow_UnsafeSerial
+ * Method:    read
+ * Signature: (Ljava/nio/ByteBuffer;)I
+ */
+JNIEXPORT jint JNICALL Java_ch_jodersky_flow_UnsafeSerial_read
+  (JNIEnv *, jobject, jobject);
+
+/*
+ * Class:     ch_jodersky_flow_UnsafeSerial
+ * Method:    cancelRead
+ * Signature: ()V
+ */
+JNIEXPORT void JNICALL Java_ch_jodersky_flow_UnsafeSerial_cancelRead
+  (JNIEnv *, jobject);
+
+/*
+ * Class:     ch_jodersky_flow_UnsafeSerial
+ * Method:    write
+ * Signature: (Ljava/nio/ByteBuffer;I)I
+ */
+JNIEXPORT jint JNICALL Java_ch_jodersky_flow_UnsafeSerial_write
+  (JNIEnv *, jobject, jobject, jint);
+
+/*
+ * Class:     ch_jodersky_flow_UnsafeSerial
+ * Method:    close
+ * Signature: ()V
+ */
+JNIEXPORT void JNICALL Java_ch_jodersky_flow_UnsafeSerial_close
+  (JNIEnv *, jobject);
+
+#ifdef __cplusplus
+}
+#endif
+#endif
diff --git a/flow-native/src/include/ch_jodersky_flow_UnsafeSerial__.h b/flow-native/src/include/ch_jodersky_flow_UnsafeSerial__.h
new file mode 100644
index 0000000..617875f
--- /dev/null
+++ b/flow-native/src/include/ch_jodersky_flow_UnsafeSerial__.h
@@ -0,0 +1,29 @@
+/* DO NOT EDIT THIS FILE - it is machine generated */
+#include <jni.h>
+/* Header for class ch_jodersky_flow_UnsafeSerial__ */
+
+#ifndef _Included_ch_jodersky_flow_UnsafeSerial__
+#define _Included_ch_jodersky_flow_UnsafeSerial__
+#ifdef __cplusplus
+extern "C" {
+#endif
+/*
+ * Class:     ch_jodersky_flow_UnsafeSerial__
+ * Method:    open
+ * Signature: (Ljava/lang/String;IIZI)J
+ */
+JNIEXPORT jlong JNICALL Java_ch_jodersky_flow_UnsafeSerial_00024_open
+  (JNIEnv *, jobject, jstring, jint, jint, jboolean, jint);
+
+/*
+ * Class:     ch_jodersky_flow_UnsafeSerial__
+ * Method:    debug
+ * Signature: (Z)V
+ */
+JNIEXPORT void JNICALL Java_ch_jodersky_flow_UnsafeSerial_00024_debug
+  (JNIEnv *, jobject, jboolean);
+
+#ifdef __cplusplus
+}
+#endif
+#endif
diff --git a/flow-native/src/include/com_github_jodersky_flow_internal_NativeSerial.h b/flow-native/src/include/com_github_jodersky_flow_internal_NativeSerial.h
deleted file mode 100644
index 04364fb..0000000
--- a/flow-native/src/include/com_github_jodersky_flow_internal_NativeSerial.h
+++ /dev/null
@@ -1,83 +0,0 @@
-/* DO NOT EDIT THIS FILE - it is machine generated */
-#include <jni.h>
-/* Header for class com_github_jodersky_flow_internal_NativeSerial */
-
-#ifndef _Included_com_github_jodersky_flow_internal_NativeSerial
-#define _Included_com_github_jodersky_flow_internal_NativeSerial
-#ifdef __cplusplus
-extern "C" {
-#endif
-#undef com_github_jodersky_flow_internal_NativeSerial_PARITY_NONE
-#define com_github_jodersky_flow_internal_NativeSerial_PARITY_NONE 0L
-#undef com_github_jodersky_flow_internal_NativeSerial_PARITY_ODD
-#define com_github_jodersky_flow_internal_NativeSerial_PARITY_ODD 1L
-#undef com_github_jodersky_flow_internal_NativeSerial_PARITY_EVEN
-#define com_github_jodersky_flow_internal_NativeSerial_PARITY_EVEN 2L
-/*
- * Class:     com_github_jodersky_flow_internal_NativeSerial
- * Method:    open
- * Signature: (Ljava/lang/String;IIZI)J
- */
-JNIEXPORT jlong JNICALL Java_com_github_jodersky_flow_internal_NativeSerial_open
-  (JNIEnv *, jclass, jstring, jint, jint, jboolean, jint);
-
-/*
- * Class:     com_github_jodersky_flow_internal_NativeSerial
- * Method:    readDirect
- * Signature: (JLjava/nio/ByteBuffer;)I
- */
-JNIEXPORT jint JNICALL Java_com_github_jodersky_flow_internal_NativeSerial_readDirect
-  (JNIEnv *, jclass, jlong, jobject);
-
-/*
- * Class:     com_github_jodersky_flow_internal_NativeSerial
- * Method:    read
- * Signature: (J[B)I
- */
-JNIEXPORT jint JNICALL Java_com_github_jodersky_flow_internal_NativeSerial_read
-  (JNIEnv *, jclass, jlong, jbyteArray);
-
-/*
- * Class:     com_github_jodersky_flow_internal_NativeSerial
- * Method:    cancelRead
- * Signature: (J)V
- */
-JNIEXPORT void JNICALL Java_com_github_jodersky_flow_internal_NativeSerial_cancelRead
-  (JNIEnv *, jclass, jlong);
-
-/*
- * Class:     com_github_jodersky_flow_internal_NativeSerial
- * Method:    writeDirect
- * Signature: (JLjava/nio/ByteBuffer;I)I
- */
-JNIEXPORT jint JNICALL Java_com_github_jodersky_flow_internal_NativeSerial_writeDirect
-  (JNIEnv *, jclass, jlong, jobject, jint);
-
-/*
- * Class:     com_github_jodersky_flow_internal_NativeSerial
- * Method:    write
- * Signature: (J[BI)I
- */
-JNIEXPORT jint JNICALL Java_com_github_jodersky_flow_internal_NativeSerial_write
-  (JNIEnv *, jclass, jlong, jbyteArray, jint);
-
-/*
- * Class:     com_github_jodersky_flow_internal_NativeSerial
- * Method:    close
- * Signature: (J)V
- */
-JNIEXPORT void JNICALL Java_com_github_jodersky_flow_internal_NativeSerial_close
-  (JNIEnv *, jclass, jlong);
-
-/*
- * Class:     com_github_jodersky_flow_internal_NativeSerial
- * Method:    debug
- * Signature: (Z)V
- */
-JNIEXPORT void JNICALL Java_com_github_jodersky_flow_internal_NativeSerial_debug
-  (JNIEnv *, jclass, jboolean);
-
-#ifdef __cplusplus
-}
-#endif
-#endif
diff --git a/flow-native/src/include/flow.h b/flow-native/src/include/flow.h
index 44e2a47..e3f33b9 100644
--- a/flow-native/src/include/flow.h
+++ b/flow-native/src/include/flow.h
@@ -8,22 +8,25 @@ extern "C" {
 #include <stdbool.h>
 #include <stddef.h>
 
-//general error codes that are returned by functions
-#define E_IO -1 //IO error
-#define E_ACCESS_DENIED -2 //access denied
-#define E_BUSY -3 // port is busy
-#define E_INVALID_SETTINGS -4 // some port settings are invalid
-#define E_INTERRUPT -5 // not really an error, function call aborted because port is closed
-#define E_NO_PORT -6 //requested port does not exist
+// general error codes, whose that are returned by functions
+#define E_IO 1 // IO error
+#define E_ACCESS_DENIED 2 // access denied
+#define E_BUSY 3 // port is busy
+#define E_INVALID_SETTINGS 4 // some port settings are invalid
+#define E_INTERRUPT 5 // not really an error, function call aborted because port is closed
+#define E_NO_PORT 6 // requested port does not exist
 
 #define PARITY_NONE 0
 #define PARITY_ODD 1
 #define PARITY_EVEN 2
 
-/** Contains internal configuration of an open serial port. */
+/**
+ * Contains internal configuration of an open serial port.
+ */
 struct serial_config;
 
-/**Opens a serial port and allocates memory for storing configuration. Note: if this function fails,
+/**
+ * Opens a serial port and allocates memory for storing configuration. Note: if this function fails,
  * any internally allocated resources will be freed.
  * @param port_name name of port
  * @param baud baud rate
@@ -32,59 +35,69 @@ struct serial_config;
  * @param parity kind of parity checking to use
  * @param serial pointer to memory that will be allocated with a serial structure
  * @return 0 on success
- * @return E_NO_PORT if the given port does not exist
- * @return E_ACCESS_DENIED if permissions are not sufficient to open port
- * @return E_BUSY if port is already in use
- * @return E_INVALID_SETTINGS if any of the specified settings are invalid
- * @return E_IO on other error */
+ * @return -E_NO_PORT if the given port does not exist
+ * @return -E_ACCESS_DENIED if permissions are not sufficient to open port
+ * @return -E_BUSY if port is already in use
+ * @return -E_INVALID_SETTINGS if any of the specified settings are invalid
+ * @return -E_IO on other error
+ */
 int serial_open(
-    const char* port_name,
-    int baud,
-    int char_size,
-    bool two_stop_bits,
-    int parity,
-    struct serial_config** const serial);
+	const char* port_name,
+	int baud,
+	int char_size,
+	bool two_stop_bits,
+	int parity,
+	struct serial_config** const serial);
 
-/**Closes a previously opened serial port and frees memory containing the configuration. Note: after a call to
+/**
+ * Closes a previously opened serial port and frees memory containing the configuration. Note: after a call to
  * this function, the 'serial' pointer will become invalid, make sure you only call it once. This function is NOT
- * thread safe, make sure no read or write is in prgress when this function is called (the reason is that per 
- * close manual page, close should not be called on a file descriptor that is in use by another thread). 
+ * thread safe, make sure no read or write is in prgress when this function is called (the reason is that per
+ * close manual page, close should not be called on a file descriptor that is in use by another thread).
  * @param serial pointer to serial configuration that is to be closed (and freed)
  * @return 0 on success
- * @return E_IO on error */
+ * @return -E_IO on error
+ */
 int serial_close(struct serial_config* const serial);
 
-/**Starts a read from a previously opened serial port. The read is blocking, however it may be
+/**
+ * Starts a read from a previously opened serial port. The read is blocking, however it may be
  * interrupted by calling 'serial_cancel_read' on the given serial port.
  * @param serial pointer to serial configuration from which to read
  * @param buffer buffer into which data is read
  * @param size maximum buffer size
  * @return n>0 the number of bytes read into buffer
- * @return E_INTERRUPT if the call to this function was interrupted
- * @return E_IO on IO error */
+ * @return -E_INTERRUPT if the call to this function was interrupted
+ * @return -E_IO on IO error
+ */
 int serial_read(struct serial_config* const serial, char* const buffer, size_t size);
 
-/**Cancels a blocked read call. This function is thread safe, i.e. it may be called from a thread even
+/**
+ * Cancels a blocked read call. This function is thread safe, i.e. it may be called from a thread even
  * while another thread is blocked in a read call.
  * @param serial_config the serial port to interrupt
  * @return 0 on success
- * @return E_IO on error */
+ * @return -E_IO on error
+ */
 int serial_cancel_read(struct serial_config* const serial);
 
-/**Writes data to a previously opened serial port. Non bocking.
+/**
+ * Writes data to a previously opened serial port. Non bocking.
  * @param serial pointer to serial configuration to which to write
  * @param data data to write
  * @param size number of bytes to write from data
  * @return n>0 the number of bytes written
- * @return E_IO on IO error */
+ * @return -E_IO on IO error
+ */
 int serial_write(struct serial_config* const serial, char* const data, size_t size);
 
-/**Sets debugging option. If debugging is enabled, detailed error message are printed from method calls. */
+/**
+ * Sets debugging option. If debugging is enabled, detailed error message are printed from method calls.
+ */
 void serial_debug(bool value);
 
 #ifdef __cplusplus
 }
 #endif
 
-
 #endif /* FLOW_H */
diff --git a/flow-native/src/platform/posix/flow.c b/flow-native/src/platform/posix/flow.c
index a2a239c..969949b 100644
--- a/flow-native/src/platform/posix/flow.c
+++ b/flow-native/src/platform/posix/flow.c
@@ -5,64 +5,77 @@
 #include <termios.h>
 #include <fcntl.h>
 #include <sys/file.h>
+#include <sys/select.h>
 #include "flow.h"
 
-
 #define DATA_CANCEL 0xffffffff
 
 static bool debug = false;
-#define DEBUG(f) if (debug) {f}
 
-void serial_debug(bool value) {
-    debug = value;
+static void print_debug(const char* const msg, int en)
+{
+	if (debug) {
+		if (errno == 0) {
+			fprintf(stderr, "%s", msg);
+		} else {
+			fprintf(stderr, "%s: %d\n", msg, en);
+		}
+		fflush(stderr);
+	}
+}
+
+void serial_debug(bool value)
+{
+	debug = value;
 }
 
 //contains file descriptors used in managing a serial port
 struct serial_config {
-    int port_fd; // file descriptor of serial port
+	int port_fd; // file descriptor of serial port
 
-    /* a pipe is used to abort a serial read by writing something into the
-     * write end of the pipe */
-    int pipe_read_fd; // file descriptor, read end of pipe
-    int pipe_write_fd; // file descriptor, write end of pipe
+	/* a pipe is used to abort a serial read by writing something into the
+	 * write end of the pipe */
+	int pipe_read_fd; // file descriptor, read end of pipe
+	int pipe_write_fd; // file descriptor, write end of pipe
 };
 
 int serial_open(
-    const char* const port_name,
-    int baud,
-    int char_size,
-    bool two_stop_bits,
-    int parity,
-    struct serial_config** serial) {
-
-    int fd = open(port_name, O_RDWR | O_NOCTTY | O_NONBLOCK);
-  
-    if (fd < 0) {
-        int en = errno;
-        DEBUG(perror("error obtaining port file descriptor"););
-        if (en == EACCES) return E_ACCESS_DENIED;
-        if (en == ENOENT) return E_NO_PORT;
-        return E_IO;
-    }
-  
-    if (flock(fd, LOCK_EX | LOCK_NB) < 0) {
-        DEBUG(perror("error acquiring lock on port"););
-        close(fd);
-        return E_BUSY;
-    }
-  
-    /* configure new port settings */
-    struct termios newtio;
-  
-    /* initialize serial interface */
-    newtio.c_iflag = 0;
-    newtio.c_oflag = 0;
-    newtio.c_lflag = 0;
-    newtio.c_cflag = CREAD;
-  
-    /* set speed */
-    speed_t bd;
-    switch (baud) {
+	const char* const port_name,
+	int baud,
+	int char_size,
+	bool two_stop_bits,
+	int parity,
+	struct serial_config** serial)
+{
+
+	int fd = open(port_name, O_RDWR | O_NOCTTY | O_NONBLOCK);
+
+	if (fd < 0) {
+		int en = errno;
+		print_debug("Error obtaining file descriptor for port", en);
+		if (en == EACCES) return -E_ACCESS_DENIED;
+		if (en == ENOENT) return -E_NO_PORT;
+		return -E_IO;
+	}
+
+	if (flock(fd, LOCK_EX | LOCK_NB) < 0) {
+		print_debug("Error acquiring lock on port", errno);
+		close(fd);
+		return -E_BUSY;
+	}
+
+	/* configure new port settings */
+	struct termios newtio;
+
+	/* initialize serial interface */
+	newtio.c_iflag = 0;
+	newtio.c_oflag = 0;
+	newtio.c_lflag = 0;
+	newtio.c_cflag = CREAD;
+
+	/* set speed */
+	speed_t bd;
+	switch (baud) {
         case 50: bd = B50; break;
         case 75: bd = B75; break;
         case 110: bd = B110; break;
@@ -82,166 +95,169 @@ int serial_open(
         case 115200: bd = B115200; break;
         case 230400: bd = B230400; break;
         default:
-            close(fd);
-            DEBUG(fprintf(stderr, "invalid baud rate %d\n", baud););
-            return E_INVALID_SETTINGS;
-    }
-  
-    if (cfsetspeed(&newtio, bd) < 0) {
-        DEBUG(perror("error setting baud rate"););
-        close(fd);
-        return E_IO;
-    }
-
-    /* set char size*/
-    switch (char_size) {
+		close(fd);
+	        print_debug("Invalid baud rate", 0);
+		return -E_INVALID_SETTINGS;
+	}
+
+	if (cfsetspeed(&newtio, bd) < 0) {
+		print_debug("Error setting baud rate", errno);
+		close(fd);
+		return -E_IO;
+	}
+
+	/* set char size*/
+	switch (char_size) {
         case 5: newtio.c_cflag |= CS5; break;
         case 6: newtio.c_cflag |= CS6; break;
         case 7: newtio.c_cflag |= CS7; break;
         case 8: newtio.c_cflag |= CS8; break;
         default:
-            close(fd);
-            DEBUG(fprintf(stderr, "invalid character size %d\n", char_size););
-            return E_INVALID_SETTINGS;
-    }
-  
-    /* use two stop bits */
-    if (two_stop_bits){
-        newtio.c_cflag |= CSTOPB;
-    }
-  
-    /* set parity */
-    switch (parity) {
+		close(fd);
+		print_debug("Invalid character size", 0);
+		return -E_INVALID_SETTINGS;
+	}
+
+	/* use two stop bits */
+	if (two_stop_bits){
+		newtio.c_cflag |= CSTOPB;
+	}
+
+	/* set parity */
+	switch (parity) {
         case PARITY_NONE: break;
         case PARITY_ODD: newtio.c_cflag |= (PARENB | PARODD); break;
         case PARITY_EVEN: newtio.c_cflag |= PARENB; break;
         default:
-            close(fd);
-            DEBUG(fprintf(stderr, "invalid parity %d\n", parity););
-            return E_INVALID_SETTINGS;
-    }
-  
-    if (tcflush(fd, TCIOFLUSH) < 0) {
-        DEBUG(perror("error flushing serial settings"););
-        close(fd);
-        return E_IO;
-    }
-  
-    if (tcsetattr(fd, TCSANOW, &newtio) < 0) {
-        DEBUG(perror("error applying serial settings"););
-        close(fd);
-        return E_IO;
-    }
-  
-    int pipe_fd[2];
-    if (pipe(pipe_fd) < 0) {
-        DEBUG(perror("error opening pipe"););
-        close(fd);
-        return E_IO;
-    }
-  
-    if (fcntl(pipe_fd[0], F_SETFL, O_NONBLOCK) < 0 || fcntl(pipe_fd[1], F_SETFL, O_NONBLOCK) < 0) {
-        DEBUG(perror("error setting pipe to non-blocking"););
-        close(fd);
-        close(pipe_fd[0]);
-        close(pipe_fd[1]);
-        return E_IO;
-    }
-  
-    struct serial_config* s = malloc(sizeof(s));
-    if (s == NULL) {
-        DEBUG(perror("error allocating memory for serial configuration"););
-        close(fd);
-        close(pipe_fd[0]);
-        close(pipe_fd[1]);
-        return E_IO;
-    }
-  
-    s->port_fd = fd;
-    s->pipe_read_fd = pipe_fd[0];
-    s->pipe_write_fd = pipe_fd[1];
-    (*serial) = s;
-  
-    return 0;
+		close(fd);
+		print_debug("Invalid parity", 0);
+		return -E_INVALID_SETTINGS;
+	}
+
+	if (tcflush(fd, TCIOFLUSH) < 0) {
+		print_debug("Error flushing serial settings", errno);
+		close(fd);
+		return -E_IO;
+	}
+
+	if (tcsetattr(fd, TCSANOW, &newtio) < 0) {
+		print_debug("Error applying serial settings", errno);
+		close(fd);
+		return -E_IO;
+	}
+
+	int pipe_fd[2];
+	if (pipe(pipe_fd) < 0) {
+		print_debug("Error opening pipe", errno);
+		close(fd);
+		return -E_IO;
+	}
+
+	if (fcntl(pipe_fd[0], F_SETFL, O_NONBLOCK) < 0 || fcntl(pipe_fd[1], F_SETFL, O_NONBLOCK) < 0) {
+		print_debug("Error setting pipe to non-blocking", errno);
+		close(fd);
+		close(pipe_fd[0]);
+		close(pipe_fd[1]);
+		return -E_IO;
+	}
+
+	struct serial_config* s = malloc(sizeof(s));
+	if (s == NULL) {
+		print_debug("Error allocating memory for serial configuration", errno);
+		close(fd);
+		close(pipe_fd[0]);
+		close(pipe_fd[1]);
+		return -E_IO;
+	}
+
+	s->port_fd = fd;
+	s->pipe_read_fd = pipe_fd[0];
+	s->pipe_write_fd = pipe_fd[1];
+	(*serial) = s;
+
+	return 0;
 }
 
+int serial_close(struct serial_config* const serial)
+{
+	if (close(serial->pipe_write_fd) < 0) {
+		print_debug("Error closing write end of pipe", errno);
+		return -E_IO;
+	}
+	if (close(serial->pipe_read_fd) < 0) {
+		print_debug("Error closing read end of pipe", errno);
+		return -E_IO;
+	}
+
+	if (flock(serial->port_fd, LOCK_UN) < 0){
+		print_debug("Error releasing lock on port", errno);
+		return -E_IO;
+	}
+	if (close(serial->port_fd) < 0) {
+		print_debug("Error closing port", errno);
+		return -E_IO;
+	}
 
-int serial_close(struct serial_config* const serial) {
-    if (close(serial->pipe_write_fd) < 0) {
-        DEBUG(perror("error closing write end of pipe"););
-        return E_IO;
-    }
-    if (close(serial->pipe_read_fd) < 0) {
-        DEBUG(perror("error closing read end of pipe"););
-        return E_IO;
-    }
-  
-    if (flock(serial->port_fd, LOCK_UN) < 0){
-        DEBUG(perror("error releasing lock on port"););
-        return E_IO;
-    }
-    if (close(serial->port_fd) < 0) {
-        DEBUG(perror("error closing port"););
-        return E_IO;
-    }
-  
-    free(serial);
-    return 0;
+	free(serial);
+	return 0;
 }
 
-int serial_read(struct serial_config* const serial, char* const buffer, size_t size) {
-    int port = serial->port_fd;
-    int pipe = serial->pipe_read_fd;
-
-    fd_set rfds;
-    FD_ZERO(&rfds);
-    FD_SET(port, &rfds);
-    FD_SET(pipe, &rfds);
-  
-    int nfds = pipe + 1;
-    if (pipe < port) nfds = port + 1;
-  
-    int n = select(nfds, &rfds, NULL, NULL, NULL);
-    if (n < 0) {
-        DEBUG(perror("error trying to call select on port and pipe"););
-        return E_IO;
-    }
-
-    if (FD_ISSET(pipe, &rfds)) {
-        return E_INTERRUPT;
-    } else if (FD_ISSET(port, &rfds)) {
-        int r = read(port, buffer, size);
-    
-        //treat 0 bytes read as an error to avoid problems on disconnect
-        //anyway, after a poll there should be more than 0 bytes available to read
-        if (r <= 0) {
-            DEBUG(perror("error data not available after select"););
-            return E_IO;
-        }
-        return r;
-    } else {
-        fprintf(stderr, "select returned unknown read sets\n");
-        return E_IO;
-    }
+int serial_read(struct serial_config* const serial, char* const buffer, size_t size)
+{
+	int port = serial->port_fd;
+	int pipe = serial->pipe_read_fd;
+
+	fd_set rfds;
+	FD_ZERO(&rfds);
+	FD_SET(port, &rfds);
+	FD_SET(pipe, &rfds);
+
+	int nfds = pipe + 1;
+	if (pipe < port) nfds = port + 1;
+
+	int n = select(nfds, &rfds, NULL, NULL, NULL);
+	if (n < 0) {
+		print_debug("Error trying to call select on port and pipe", errno);
+		return -E_IO;
+	}
+
+	if (FD_ISSET(pipe, &rfds)) {
+		return -E_INTERRUPT;
+	} else if (FD_ISSET(port, &rfds)) {
+		int r = read(port, buffer, size);
+
+		// treat 0 bytes read as an error to avoid problems on disconnect
+		// anyway, after a poll there should be more than 0 bytes available to read
+		if (r <= 0) {
+			print_debug("Error data not available after select", errno);
+			return -E_IO;
+		}
+		return r;
+	} else {
+		print_debug("Select returned unknown read sets", 0);
+		return -E_IO;
+	}
 }
 
-int serial_cancel_read(struct serial_config* const serial) {
-    int data = DATA_CANCEL;
-  
-    //write to pipe to wake up any blocked read thread (self-pipe trick)
-    if (write(serial->pipe_write_fd, &data, 1) < 0) {
-        DEBUG(perror("error writing to pipe during read cancel"););
-        return E_IO;
-    }
-  
-    return 0;
+int serial_cancel_read(struct serial_config* const serial)
+{
+	int data = DATA_CANCEL;
+
+	//write to pipe to wake up any blocked read thread (self-pipe trick)
+	if (write(serial->pipe_write_fd, &data, 1) < 0) {
+		print_debug("Error writing to pipe during read cancel", errno);
+		return -E_IO;
+	}
+
+	return 0;
 }
 
-int serial_write(struct serial_config* const serial, char* const data, size_t size) {
-    int r = write(serial->port_fd, data, size);
-    if (r < 0) {
-        DEBUG(perror("error writing to port"););
-        return E_IO;
-    }
-    return r;
-}
\ No newline at end of file
+int serial_write(struct serial_config* const serial, char* const data, size_t size)
+{
+	int r = write(serial->port_fd, data, size);
+	if (r < 0) {
+		print_debug("Error writing to port", errno);
+		return -E_IO;
+	}
+	return r;
+}