Add I/O library for Raspberry Pi and similar Linux-based micro computers

java/libraries/io/build.xml

@@ -0,0 +1,32 @@
+<?xml version="1.0"?>
+<project name="Processing I/O Library" default="build">
+
+  <target name="clean" description="Clean the build directories">
+    <delete dir="bin" />
+    <delete file="library/io.jar" />
+  </target>
+
+  <target name="compile" description="Compile sources">
+    <condition property="core-built">
+      <available file="../../../core/library/core.jar" />
+    </condition>
+    <fail unless="core-built" message="Please build the core library first and make sure it sits in ../../../core/library/core.jar" />
+
+    <mkdir dir="bin" />
+    <javac source="1.7"
+	   target="1.7"
+	   srcdir="src" destdir="bin" 
+	   encoding="UTF-8"
+	   includeAntRuntime="false"
+	   classpath="../../../core/library/core.jar"
+	   nowarn="true"
+	   compiler="org.eclipse.jdt.core.JDTCompilerAdapter">
+      <compilerclasspath path="../../mode/org.eclipse.jdt.core.jar; 
+                               ../../mode/jdtCompilerAdapter.jar" />
+    </javac>
+  </target>
+
+  <target name="build" depends="compile" description="Build I/O library">
+    <jar basedir="bin" destfile="library/io.jar" />
+  </target>
+</project>

java/libraries/io/library.properties

@@ -0,0 +1,2 @@
+name = I/O
+version = 1

java/libraries/io/library/export.txt

@@ -0,0 +1 @@
+name = I/O for Raspberry Pi and other Linux-based computers

java/libraries/io/src/native/Makefile

@@ -0,0 +1,17 @@
+TARGET := libprocessing-io.so
+OBJS := impl.o
+CC := gcc
+
+CFLAGS := -std=c99 -fPIC -g
+CFLAGS += -I$(shell dirname $(shell realpath $(shell which javac)))/../include
+CFLAGS += -I$(shell dirname $(shell realpath $(shell which javac)))/../include/linux
+LDFLAGS := -shared
+
+$(TARGET): $(OBJS)
+	$(CC) $(CFLAGS) $(LDFLAGS) $^ -o $@
+
+iface.h:
+	javah -classpath .. -o iface.h processing.io.NativeInterface
+
+clean:
+	rm -f $(TARGET) $(OBJS)

java/libraries/io/src/native/impl.c

@@ -0,0 +1,241 @@
+/*
+  Copyright (c) The Processing Foundation 2015
+  I/O library developed by Gottfried Haider as part of GSOC 2015
+
+  This library is free software; you can redistribute it and/or
+  modify it under the terms of the GNU Lesser General Public
+  License as published by the Free Software Foundation; either
+  version 2.1 of the License, or (at your option) any later version.
+
+  This library is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General
+  Public License along with this library; if not, write to the
+  Free Software Foundation, Inc., 59 Temple Place, Suite 330,
+  Boston, MA  02111-1307  USA
+*/
+
+#include <errno.h>
+#include <fcntl.h>
+#include <jni.h>
+#include <linux/i2c.h>
+#include <linux/i2c-dev.h>
+#include <linux/spi/spidev.h>
+#include <poll.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/ioctl.h>
+#include <sys/param.h>
+#include <unistd.h>
+#include "iface.h"
+
+
+JNIEXPORT jint JNICALL Java_processing_io_NativeInterface_openDevice
+  (JNIEnv *env, jclass cls, jstring _fn)
+{
+	const char *fn = (*env)->GetStringUTFChars(env, _fn, JNI_FALSE);
+	int file = open(fn, O_RDWR);
+	(*env)->ReleaseStringUTFChars(env, _fn, fn);
+	if (file < 0) {
+		return -errno;
+	} else {
+		return file;
+	}
+}
+
+
+JNIEXPORT jstring JNICALL Java_processing_io_NativeInterface_getError
+  (JNIEnv *env, jclass cls, jint _errno)
+{
+	char *msg = strerror(abs(_errno));
+	if (msg) {
+		return (*env)->NewStringUTF(env, msg);
+	} else {
+		return NULL;
+	}
+}
+
+
+JNIEXPORT jint JNICALL Java_processing_io_NativeInterface_closeDevice
+  (JNIEnv *env, jclass cls, jint handle)
+{
+	if (close(handle) < 0) {
+		return -errno;
+	} else {
+		return 0;
+	}
+}
+
+
+JNIEXPORT jint JNICALL Java_processing_io_NativeInterface_readFile
+  (JNIEnv *env, jclass cls, jstring _fn, jbyteArray _in)
+{
+	const char *fn = (*env)->GetStringUTFChars(env, _fn, JNI_FALSE);
+	int file = open(fn, O_RDONLY);
+	(*env)->ReleaseStringUTFChars(env, _fn, fn);
+	if (file < 0) {
+		return -errno;
+	}
+
+	jbyte *in = (*env)->GetByteArrayElements(env, _in, NULL);
+	int len = read(file, in, (*env)->GetArrayLength(env, _in));
+	if (len < 0) {
+		len = -errno;
+	}
+	(*env)->ReleaseByteArrayElements(env, _in, in, 0);
+
+	close(file);
+	return len;
+}
+
+
+JNIEXPORT jint JNICALL Java_processing_io_NativeInterface_writeFile
+  (JNIEnv *env, jclass cls, jstring _fn, jbyteArray _out)
+{
+	const char *fn = (*env)->GetStringUTFChars(env, _fn, JNI_FALSE);
+	int file = open(fn, O_WRONLY);
+	(*env)->ReleaseStringUTFChars(env, _fn, fn);
+	if (file < 0) {
+		return -errno;
+	}
+
+	jbyte *out = (*env)->GetByteArrayElements(env, _out, JNI_FALSE);
+	int len = write(file, out, (*env)->GetArrayLength(env, _out));
+	if (len < 0) {
+		len = -errno;
+	}
+	(*env)->ReleaseByteArrayElements(env, _out, out, JNI_ABORT);
+
+	close(file);
+	return len;
+}
+
+
+JNIEXPORT jint JNICALL Java_processing_io_NativeInterface_pollDevice
+  (JNIEnv *env, jclass cls, jstring _fn, jint timeout)
+{
+	const char *fn = (*env)->GetStringUTFChars(env, _fn, JNI_FALSE);
+	int file = open(fn, O_RDONLY|O_NONBLOCK);
+	(*env)->ReleaseStringUTFChars(env, _fn, fn);
+	if (file < 0) {
+		return -errno;
+	}
+
+	// dummy read
+	char tmp;
+	while (0 < read(file, &tmp, 1));
+
+	struct pollfd fds[1];
+	memset(fds, 0, sizeof(fds));
+	fds[0].fd = file;
+	fds[0].events = POLLPRI|POLLERR;
+
+	// and wait
+	int ret = poll(fds, 1, timeout);
+	close(file);
+
+	if (ret < 0) {
+		return -errno;
+	} else if (ret == 0) {
+		// timeout
+		return 0;
+	} else if (fds[0].revents & POLLPRI) {
+		// interrupt
+		return 1;
+	} else {
+		// POLLERR?
+		return -ENOMSG;
+	}
+}
+
+
+JNIEXPORT jint JNICALL Java_processing_io_NativeInterface_transferI2c
+  (JNIEnv *env, jclass cls, jint handle, jint slave, jbyteArray _out, jbyteArray _in)
+{
+	struct i2c_rdwr_ioctl_data packets;
+	struct i2c_msg msgs[2];
+	jbyte *out, *in;
+
+	packets.msgs = msgs;
+
+	msgs[0].addr = slave;
+	msgs[0].flags = 0;
+	msgs[0].len = (*env)->GetArrayLength(env, _out);
+	out = (*env)->GetByteArrayElements(env, _out, NULL);
+	msgs[0].buf = out;
+	if (_in != NULL) {
+		in = (*env)->GetByteArrayElements(env, _in, NULL);
+		msgs[1].addr = slave;
+		msgs[1].flags = I2C_M_RD;	// I2C_M_RECV_LEN is not supported
+		msgs[1].len = (*env)->GetArrayLength(env, _in);
+		msgs[1].buf = in;
+		packets.nmsgs = 2;
+	} else {
+		packets.nmsgs = 1;
+	}
+
+	int ret = ioctl(handle, I2C_RDWR, &packets);
+	if (ret < 0) {
+		ret = -errno;
+	}
+
+	(*env)->ReleaseByteArrayElements(env, _out, out, JNI_ABORT);
+	if (_in != NULL) {
+		(*env)->ReleaseByteArrayElements(env, _in, in, 0);
+	}
+
+	return ret;
+}
+
+
+JNIEXPORT jint JNICALL Java_processing_io_NativeInterface_setSpiSettings
+  (JNIEnv *env, jclass cls, jint handle, jint _maxSpeed, jint dataOrder, jint mode)
+{
+	uint8_t tmp;
+	uint32_t maxSpeed;
+
+	tmp = (uint8_t)mode;
+	int ret = ioctl(handle, SPI_IOC_WR_MODE, &tmp);
+	if (ret < 0) {
+		return ret;
+	}
+
+	tmp = (uint8_t)dataOrder;
+	ret = ioctl(handle, SPI_IOC_WR_LSB_FIRST, &tmp);
+	if (ret < 0) {
+		return ret;
+	}
+
+	maxSpeed = (uint32_t)_maxSpeed;
+	ret = ioctl(handle, SPI_IOC_WR_MAX_SPEED_HZ, &maxSpeed);
+	if (ret < 0) {
+		return ret;
+	}
+
+	return 0;
+}
+
+
+JNIEXPORT jint JNICALL Java_processing_io_NativeInterface_transferSpi
+  (JNIEnv *env, jclass cls, jint handle, jbyteArray _out, jbyteArray _in)
+{
+	jbyte* out = (*env)->GetByteArrayElements(env, _out, NULL);
+	jbyte* in = (*env)->GetByteArrayElements(env, _in, NULL);
+
+	struct spi_ioc_transfer xfer = {
+		.tx_buf = (unsigned long)out,
+		.rx_buf = (unsigned long)in,
+		.len = MIN((*env)->GetArrayLength(env, _out), (*env)->GetArrayLength(env, _in)),
+	};
+
+	int ret = ioctl(handle, SPI_IOC_MESSAGE(1), &xfer);
+
+	(*env)->ReleaseByteArrayElements(env, _out, out, JNI_ABORT);
+	(*env)->ReleaseByteArrayElements(env, _in, in, 0);
+
+	return ret;
+}