Alexander--/gist:f3173d4425d7a3461dcd6b71b356ec0f

## gistfile1.txt
JNIEXPORT jint JNICALL Java_io_netty_channel_android_JNI_bind(JNIEnv *env, jclass type, jint a1, jint a2, jint a3, jint a4, jint port, jint fd) {
    struct sockaddr* address;
    socklen_t size;

    if (a1 == 0 && a2 == 0 && a3 == 0xff) {
        size = sizeof(struct sockaddr_in);

        struct sockaddr_in* ip4 = alloca(size);

        *ip4 = (struct sockaddr_in) {
                .sin_family = AF_INET,
                .sin_port =  htons((uint16_t) port),
        };

        uint32_t* a = (uint32_t*) (&ip4->sin_addr.s_addr);

        *a = *(uint32_t*) &a4;

        address = (struct sockaddr*)(void*) ip4;
    } else {
        size = sizeof(struct sockaddr_in6);

        struct sockaddr_in6* ip6 = alloca(size);

        *ip6 = (struct sockaddr_in6) {
                .sin6_family = AF_INET6,
                .sin6_port =  htons((uint16_t) port),
        };

        uint32_t* a = (uint32_t*) (&ip6->sin6_addr.s6_addr);

        a[0] = *(uint32_t*) &a1;
        a[1] = *(uint32_t*) &a2;
        a[2] = *(uint32_t*) &a3;
        a[3] = *(uint32_t*) &a4;

        address = (struct sockaddr*)(void*) ip6;
    }

    return bind(fd, address, size) == -1 ? -errno : 0;
}

JNIEXPORT jint JNICALL Java_io_netty_channel_android_JNI_connect(JNIEnv *env, jclass type, jint a1, jint a2, jint a3, jint a4, jint port, jint fd) {
    struct sockaddr* address;
    socklen_t size;

    if (a1 == 0 && a2 == 0 && a3 == 0xff) {
        size = sizeof(struct sockaddr_in);

        struct sockaddr_in* ip4 = alloca(size);

        *ip4 = (struct sockaddr_in) {
                .sin_family = AF_INET,
                .sin_port =  htons((uint16_t) port),
        };

        uint32_t* a = (uint32_t*) (&ip4->sin_addr.s_addr);

        a[0] = *(uint32_t*) &a4;

        address = (struct sockaddr*)(void*) ip4;
    } else {
        size = sizeof(struct sockaddr_in6);

        struct sockaddr_in6* ip6 = alloca(size);

        *ip6 = (struct sockaddr_in6) {
                .sin6_family = AF_INET6,
                .sin6_port =  htons((uint16_t) port),
        };

        uint32_t* a = (uint32_t*) (&ip6->sin6_addr.s6_addr);

        a[0] = *(uint32_t*) &a1;
        a[1] = *(uint32_t*) &a2;
        a[2] = *(uint32_t*) &a3;
        a[3] = *(uint32_t*) &a4;

        address = (struct sockaddr*)(void*) ip6;
    }

    int res = connect(fd, address, size);

    if (res != -1) {
        return 0;
    }

    int err = errno;

    return err == EINPROGRESS ? 1 : -err;
}

JNIEXPORT jint JNICALL Java_io_netty_channel_android_JNI_dw(JNIEnv *env, jclass type, jobject direct, jint fd, jint position, jint amount) {
    char* bytes = (*env)->GetDirectBufferAddress(env, direct);

    ssize_t res = write(fd, bytes + position, (size_t) amount);

    return (jint) (res == -1 ? -errno : res);
}

JNIEXPORT jint JNICALL Java_io_netty_channel_android_JNI_hw(JNIEnv *env, jclass type, jbyteArray array_, jint fd, jint pos, jint amount) {
    jbyte *array = (*env)->GetPrimitiveArrayCritical(env, array_, NULL);

    ssize_t res = write(fd, array + pos, (size_t) amount);

    (*env)->ReleasePrimitiveArrayCritical(env, array_, array, 0);

    return (jint) (res == -1 ? -errno : res);
}

JNIEXPORT jint JNICALL Java_io_netty_channel_android_JNI_dr(JNIEnv *env, jclass type, jobject direct, jint position, jint amount, jint fd) {
    char* bytes = (*env)->GetDirectBufferAddress(env, direct);
    if (bytes == NULL) {
        return ERR_NO_DIRECT;
    }

    ssize_t res = read(fd, bytes + position, (size_t) amount);

    return (jint) (res == -1 ? -errno : res);
}

JNIEXPORT jint JNICALL Java_io_netty_channel_android_JNI_hr(JNIEnv *env, jclass type, jbyteArray array_, jint position, jint amount, jint fd) {
    jbyte *array = (*env)->GetPrimitiveArrayCritical(env, array_, NULL);

    ssize_t res = read(fd, array + position, (size_t) amount);

    (*env)->ReleasePrimitiveArrayCritical(env, array_, array, 0);

    return (jint) (res == -1 ? -errno : res);
}

JNIEXPORT jint JNICALL Java_io_netty_channel_android_JNI_ds(JNIEnv *env, jclass type,
                                                            jobject b1, jobject b2, jobject b3, jobject b4, jobject b5,
                                                            jint buffers,
                                                            jint o1, jint o2, jint o3, jint o4, jint o5,
                                                            jint c1, jint c2, jint c3, jint c4, jint c5,
                                                            jint fd) {

    struct iovec* iov = alloca(sizeof(struct iovec) * buffers);

    const jobject targets[] = { b1, b2, b3, b4, b5 };
    const jint offsets[] = { o1, o2, o3, o4, o5 };
    const jint counts[] = { c1, c2, c3, c4, c5 };

    for (int i = 0; i < buffers; ++i) {
        char* base = (*env)->GetDirectBufferAddress(env, targets[i]);
        if (base == NULL) {
            return ERR_NO_DIRECT;
        }

        iov[i].iov_base = base + offsets[i];
        iov[i].iov_len = (__kernel_size_t) counts[i];
    }

    ssize_t res = (jint) writev(fd, iov, buffers);

    return (jint) (res == -1 ? -errno : res);
}

JNIEXPORT jint JNICALL Java_io_netty_channel_android_JNI_hs(JNIEnv *env, jclass type,
                                                            jbyteArray b1_, jbyteArray b2_, jbyteArray b3_, jbyteArray b4_, jbyteArray b5_,
                                                            jint buffers,
                                                            jint o1, jint o2, jint o3, jint o4, jint o5,
                                                            jint c1, jint c2, jint c3, jint c4, jint c5,
                                                            jint fd) {

    struct iovec* iov = alloca(sizeof(struct iovec) * buffers);

    const jobject targets[] = { b1_, b2_, b3_, b4_, b5_ };
    const jint offsets[] = { o1, o2, o3, o4, o5 };
    const jint counts[] = { c1, c2, c3, c4, c5 };

    for (int i = 0; i < buffers; ++i) {
        char* ptr = (*env)->GetPrimitiveArrayCritical(env, targets[i], NULL);

        iov[i].iov_base = ptr + offsets[i];
        iov[i].iov_len = (__kernel_size_t) counts[i];
    }

    ssize_t res = writev(fd, iov, buffers);

    for (int i = 0; i < buffers; ++i) {
        (*env)->ReleasePrimitiveArrayCritical(env, targets[i], iov[i].iov_base, 0);
    }

    return (jint) (res == -1 ? -errno : res);
}

JNIEXPORT jint JNICALL Java_io_netty_channel_android_JNI_dg(JNIEnv *env, jclass type,
                                     jobject b1, jobject b2, jobject b3, jobject b4, jobject b5,
                                     jint buffers,
                                     jint o1, jint o2, jint o3, jint o4, jint o5,
                                     jint c1, jint c2, jint c3, jint c4, jint c5,
                                     jint fd) {

    struct iovec* iov = alloca(sizeof(struct iovec) * buffers);

    const jobject targets[] = { b1, b2, b3, b4, b5 };
    const jint offsets[] = { o1, o2, o3, o4, o5 };
    const jint counts[] = { c1, c2, c3, c4, c5 };

    for (int i = 0; i < buffers; ++i) {
        char* base = (*env)->GetDirectBufferAddress(env, targets[i]);
        if (base == NULL) {
            return ERR_NO_DIRECT;
        }

        iov[i].iov_base = base + offsets[i];
        iov[i].iov_len = (__kernel_size_t) counts[i];
    }

    ssize_t res = (jint) readv(fd, iov, buffers);

    return (jint) (res == -1 ? -errno : res);
}

JNIEXPORT jint JNICALL Java_io_netty_channel_android_JNI_hg(JNIEnv *env, jclass type,
                                     jbyteArray b1_, jbyteArray b2_, jbyteArray b3_, jbyteArray b4_, jbyteArray b5_,
                                     jint buffers,
                                     jint o1, jint o2, jint o3, jint o4, jint o5,
                                     jint c1, jint c2, jint c3, jint c4, jint c5,
                                     jint fd) {

    struct iovec* iov = alloca(sizeof(struct iovec) * buffers);

    const jobject targets[] = { b1_, b2_, b3_, b4_, b5_ };
    const jint offsets[] = { o1, o2, o3, o4, o5 };
    const jint counts[] = { c1, c2, c3, c4, c5 };

    for (int i = 0; i < buffers; ++i) {
        char* ptr = (*env)->GetPrimitiveArrayCritical(env, targets[i], NULL);

        iov[i].iov_base = ptr + offsets[i];
        iov[i].iov_len = (__kernel_size_t) counts[i];
    }

    ssize_t res = readv(fd, iov, buffers);

    for (int i = 0; i < buffers; ++i) {
        (*env)->ReleasePrimitiveArrayCritical(env, targets[i], iov[i].iov_base, 0);
    }

    return (jint) (res == -1 ? -errno : res);
}

package io.netty.channel.android;

import android.support.annotation.NonNull;

import java.nio.ByteBuffer;
import java.nio.channels.GatheringByteChannel;
import java.nio.channels.ScatteringByteChannel;

final class FdNioChannel implements ScatteringByteChannel, GatheringByteChannel {
    private final int fd;

    FdNioChannel(int fd) {
        this.fd = fd;
    }

    private int heapScatter(@NonNull ByteBuffer[] srcs, int offset, int length) throws java.io.IOException {
        byte[] a1, a2, a3 = null, a4 = null, a5 = null;
        int o1, o2, o3 = 0, o4 = 0, o5 = 0;
        int c1, c2, c3 = 0, c4 = 0, c5 = 0;

        switch (length) {
            default:
                length = 5;
                ByteBuffer b5 = srcs[offset + 4];
                a5 = b5.array();
                o5 = b5.position() + b5.arrayOffset();
                c5 = b5.remaining();
            case 4:
                ByteBuffer b4 = srcs[offset + 3];
                a4 = b4.array();
                o4 = b4.position() + b4.arrayOffset();
                c4 = b4.remaining();
            case 3:
                ByteBuffer b3 = srcs[offset + 2];
                a3 = b3.array();
                o3 = b3.position() + b3.arrayOffset();
                c3 = b3.remaining();
            case 2:
                ByteBuffer b2 = srcs[offset + 1];
                a2 = b2.array();
                o2 = b2.position() + b2.arrayOffset();
                c2 = b2.remaining();
                ByteBuffer b1 = srcs[offset];
                a1 = b1.array();
                o1 = b1.position() + b1.arrayOffset();
                c1 = b1.remaining();
        }

        return JNI.hs(a1, a2, a3, a4, a5, length, o1, o2, o3, o4, o5, c1, c2, c3, c4, c5, fd);
    }

    private int directScatter(@NonNull ByteBuffer[] srcs, int offset, int length) throws java.io.IOException {
        ByteBuffer b1, b2, b3 = null, b4 = null, b5 = null;
        int o1, o2, o3 = 0, o4 = 0, o5 = 0;
        int c1, c2, c3 = 0, c4 = 0, c5 = 0;

        switch (length) {
            default:
                length = 5;
                b5 = srcs[offset + 4];
                o5 = b5.position();
                c5 = b5.remaining();
            case 4:
                b4 = srcs[offset + 3];
                o4 = b4.position();
                c4 = b4.remaining();
            case 3:
                b3 = srcs[offset + 2];
                o3 = b3.position();
                c3 = b3.remaining();
            case 2:
                b2 = srcs[offset + 1];
                o2 = b2.position();
                c2 = b2.remaining();
                b1 = srcs[offset];
                o1 = b1.position();
                c1 = b1.remaining();
        }

        return JNI.ds(b1, b2, b3, b4, b5, length, o1, o2, o3, o4, o5, c1, c2, c3, c4, c5, fd);
    }

    private int heapGather(@NonNull ByteBuffer[] srcs, int offset, int length) throws java.io.IOException {
        byte[] a1, a2, a3 = null, a4 = null, a5 = null;
        int o1, o2, o3 = 0, o4 = 0, o5 = 0;
        int c1, c2, c3 = 0, c4 = 0, c5 = 0;

        switch (length) {
            default:
                length = 5;
                ByteBuffer b5 = srcs[offset + 4];
                a5 = b5.array();
                o5 = b5.position() + b5.arrayOffset();
                c5 = b5.remaining();
            case 4:
                ByteBuffer b4 = srcs[offset + 3];
                a4 = b4.array();
                o4 = b4.position() + b4.arrayOffset();
                c4 = b4.remaining();
            case 3:
                ByteBuffer b3 = srcs[offset + 2];
                a3 = b3.array();
                o3 = b3.position() + b3.arrayOffset();
                c3 = b3.remaining();
            case 2:
                ByteBuffer b2 = srcs[offset + 1];
                a2 = b2.array();
                o2 = b2.position() + b2.arrayOffset();
                c2 = b2.remaining();
                ByteBuffer b1 = srcs[offset];
                a1 = b1.array();
                o1 = b1.position() + b1.arrayOffset();
                c1 = b1.remaining();
        }

        return JNI.hg(a1, a2, a3, a4, a5, length, o1, o2, o3, o4, o5, c1, c2, c3, c4, c5, fd);
    }

    private int directGather(@NonNull ByteBuffer[] srcs, int offset, int length) throws java.io.IOException {
        ByteBuffer b1, b2, b3 = null, b4 = null, b5 = null;
        int o1, o2, o3 = 0, o4 = 0, o5 = 0;
        int c1, c2, c3 = 0, c4 = 0, c5 = 0;

        switch (length) {
            default:
                length = 5;
                b5 = srcs[offset + 4];
                o5 = b5.position();
                c5 = b5.remaining();
            case 4:
                b4 = srcs[offset + 3];
                o4 = b4.position();
                c4 = b4.remaining();
            case 3:
                b3 = srcs[offset + 2];
                o3 = b3.position();
                c3 = b3.remaining();
            case 2:
                b2 = srcs[offset + 1];
                o2 = b2.position();
                c2 = b2.remaining();
                b1 = srcs[offset];
                o1 = b1.position();
                c1 = b1.remaining();
        }

        return JNI.dg(b1, b2, b3, b4, b5, length, o1, o2, o3, o4, o5, c1, c2, c3, c4, c5, fd);
    }

    @Override
    public long write(@NonNull ByteBuffer[] srcs, int offset, int length) throws java.io.IOException {
        switch (length) {
            default:
                int total = srcs[offset].isDirect()
                        ? directScatter(srcs, offset, length)
                        : heapScatter(srcs, offset, length);

                Utils.checkErrno(total);

                int written = total;

                for (int i = offset; i < offset + length; ++i) {
                    ByteBuffer b = srcs[i];

                    int remaining = b.remaining();

                    if (remaining >= written) {
                        b.position(b.position() + written);

                        break;
                    } else {
                        b.position(b.limit());

                        written -= remaining;
                    }
                }

                return total;
            case 1:
                return write(srcs[offset]);
            case 0:
                return 0;
        }
    }

    @Override
    public long read(@NonNull ByteBuffer[] dsts, int offset, int length) throws java.io.IOException {
        switch (length) {
            default:
                int total = dsts[offset].isDirect()
                        ? directGather(dsts, offset, length)
                        : heapGather(dsts, offset, length);

                Utils.checkErrno(total);

                int read = total;

                for (int i = offset; i < offset + length; ++i) {
                    ByteBuffer b = dsts[i];

                    int remaining = b.remaining();

                    if (remaining >= read) {
                        b.position(b.position() + read);

                        break;
                    } else {
                        b.position(b.limit());

                        read -= remaining;
                    }
                }

                return total;
            case 1:
                return read(dsts[offset]);
            case 0:
                return 0;
        }
    }

    @Override
    public long write(@NonNull ByteBuffer[] srcs) throws java.io.IOException {
        return write(srcs, 0, srcs.length);
    }

    @Override
    public long read(@NonNull ByteBuffer[] dsts) throws java.io.IOException {
        return write(dsts, 0, dsts.length);
    }

    @Override
    public int write(@NonNull ByteBuffer src) throws java.io.IOException {
        int written = src.isDirect() ? writeDirect(src) : writeHeap(src);

        Utils.checkErrno(written);

        src.position(src.position() + written);

        return written;
    }

    @Override
    public int read(ByteBuffer dst) throws java.io.IOException {
        int read = dst.isDirect() ? readDirect(dst) : readHeap(dst);

        Utils.checkErrno(read);

        dst.position(dst.position() + read);

        return read;
    }

    private int writeDirect(ByteBuffer direct) throws IOException {
        return JNI.dw(direct, direct.position(), direct.remaining(), fd);
    }

    private int writeHeap(ByteBuffer heap) throws IOException {
        return JNI.hw(heap.array(), heap.position() + heap.arrayOffset(), heap.remaining(), fd);
    }

    private int readDirect(ByteBuffer direct) throws IOException {
        return JNI.dr(direct, direct.position(), direct.remaining(), fd);
    }

    private int readHeap(ByteBuffer heap) throws IOException {
        return JNI.hr(heap.array(), heap.position() + heap.arrayOffset(), heap.remaining(), fd);
    }

    @Override
    public boolean isOpen() {
        return true;
    }

    @Override
    public void close() {
    }
}
	JNIEXPORT jint JNICALL Java_io_netty_channel_android_JNI_bind(JNIEnv *env, jclass type, jint a1, jint a2, jint a3, jint a4, jint port, jint fd) {
	struct sockaddr* address;
	socklen_t size;

	if (a1 == 0 && a2 == 0 && a3 == 0xff) {
	size = sizeof(struct sockaddr_in);

	struct sockaddr_in* ip4 = alloca(size);

	*ip4 = (struct sockaddr_in) {
	.sin_family = AF_INET,
	.sin_port = htons((uint16_t) port),
	};

	uint32_t* a = (uint32_t*) (&ip4->sin_addr.s_addr);

	a = (uint32_t*) &a4;

	address = (struct sockaddr)(void) ip4;
	} else {
	size = sizeof(struct sockaddr_in6);

	struct sockaddr_in6* ip6 = alloca(size);

	*ip6 = (struct sockaddr_in6) {
	.sin6_family = AF_INET6,
	.sin6_port = htons((uint16_t) port),
	};

	uint32_t* a = (uint32_t*) (&ip6->sin6_addr.s6_addr);

	a[0] = (uint32_t) &a1;
	a[1] = (uint32_t) &a2;
	a[2] = (uint32_t) &a3;
	a[3] = (uint32_t) &a4;

	address = (struct sockaddr)(void) ip6;
	}

	return bind(fd, address, size) == -1 ? -errno : 0;
	}

	JNIEXPORT jint JNICALL Java_io_netty_channel_android_JNI_connect(JNIEnv *env, jclass type, jint a1, jint a2, jint a3, jint a4, jint port, jint fd) {
	struct sockaddr* address;
	socklen_t size;

	if (a1 == 0 && a2 == 0 && a3 == 0xff) {
	size = sizeof(struct sockaddr_in);

	struct sockaddr_in* ip4 = alloca(size);

	*ip4 = (struct sockaddr_in) {
	.sin_family = AF_INET,
	.sin_port = htons((uint16_t) port),
	};

	uint32_t* a = (uint32_t*) (&ip4->sin_addr.s_addr);

	a[0] = (uint32_t) &a4;

	address = (struct sockaddr)(void) ip4;
	} else {
	size = sizeof(struct sockaddr_in6);

	struct sockaddr_in6* ip6 = alloca(size);

	*ip6 = (struct sockaddr_in6) {
	.sin6_family = AF_INET6,
	.sin6_port = htons((uint16_t) port),
	};

	uint32_t* a = (uint32_t*) (&ip6->sin6_addr.s6_addr);

	a[0] = (uint32_t) &a1;
	a[1] = (uint32_t) &a2;
	a[2] = (uint32_t) &a3;
	a[3] = (uint32_t) &a4;

	address = (struct sockaddr)(void) ip6;
	}

	int res = connect(fd, address, size);

	if (res != -1) {
	return 0;
	}

	int err = errno;

	return err == EINPROGRESS ? 1 : -err;
	}

	JNIEXPORT jint JNICALL Java_io_netty_channel_android_JNI_dw(JNIEnv *env, jclass type, jobject direct, jint fd, jint position, jint amount) {
	char* bytes = (*env)->GetDirectBufferAddress(env, direct);

	ssize_t res = write(fd, bytes + position, (size_t) amount);

	return (jint) (res == -1 ? -errno : res);
	}

	JNIEXPORT jint JNICALL Java_io_netty_channel_android_JNI_hw(JNIEnv *env, jclass type, jbyteArray array_, jint fd, jint pos, jint amount) {
	jbyte array = (env)->GetPrimitiveArrayCritical(env, array_, NULL);

	ssize_t res = write(fd, array + pos, (size_t) amount);

	(*env)->ReleasePrimitiveArrayCritical(env, array_, array, 0);

	return (jint) (res == -1 ? -errno : res);
	}

	JNIEXPORT jint JNICALL Java_io_netty_channel_android_JNI_dr(JNIEnv *env, jclass type, jobject direct, jint position, jint amount, jint fd) {
	char* bytes = (*env)->GetDirectBufferAddress(env, direct);
	if (bytes == NULL) {
	return ERR_NO_DIRECT;
	}

	ssize_t res = read(fd, bytes + position, (size_t) amount);

	return (jint) (res == -1 ? -errno : res);
	}

	JNIEXPORT jint JNICALL Java_io_netty_channel_android_JNI_hr(JNIEnv *env, jclass type, jbyteArray array_, jint position, jint amount, jint fd) {
	jbyte array = (env)->GetPrimitiveArrayCritical(env, array_, NULL);

	ssize_t res = read(fd, array + position, (size_t) amount);

	(*env)->ReleasePrimitiveArrayCritical(env, array_, array, 0);

	return (jint) (res == -1 ? -errno : res);
	}

	JNIEXPORT jint JNICALL Java_io_netty_channel_android_JNI_ds(JNIEnv *env, jclass type,
	jobject b1, jobject b2, jobject b3, jobject b4, jobject b5,
	jint buffers,
	jint o1, jint o2, jint o3, jint o4, jint o5,
	jint c1, jint c2, jint c3, jint c4, jint c5,
	jint fd) {

	struct iovec* iov = alloca(sizeof(struct iovec) * buffers);

	const jobject targets[] = { b1, b2, b3, b4, b5 };
	const jint offsets[] = { o1, o2, o3, o4, o5 };
	const jint counts[] = { c1, c2, c3, c4, c5 };

	for (int i = 0; i < buffers; ++i) {
	char* base = (*env)->GetDirectBufferAddress(env, targets[i]);
	if (base == NULL) {
	return ERR_NO_DIRECT;
	}

	iov[i].iov_base = base + offsets[i];
	iov[i].iov_len = (__kernel_size_t) counts[i];
	}

	ssize_t res = (jint) writev(fd, iov, buffers);

	return (jint) (res == -1 ? -errno : res);
	}

	JNIEXPORT jint JNICALL Java_io_netty_channel_android_JNI_hs(JNIEnv *env, jclass type,
	jbyteArray b1_, jbyteArray b2_, jbyteArray b3_, jbyteArray b4_, jbyteArray b5_,
	jint buffers,
	jint o1, jint o2, jint o3, jint o4, jint o5,
	jint c1, jint c2, jint c3, jint c4, jint c5,
	jint fd) {

	struct iovec* iov = alloca(sizeof(struct iovec) * buffers);

	const jobject targets[] = { b1_, b2_, b3_, b4_, b5_ };
	const jint offsets[] = { o1, o2, o3, o4, o5 };
	const jint counts[] = { c1, c2, c3, c4, c5 };

	for (int i = 0; i < buffers; ++i) {
	char* ptr = (*env)->GetPrimitiveArrayCritical(env, targets[i], NULL);

	iov[i].iov_base = ptr + offsets[i];
	iov[i].iov_len = (__kernel_size_t) counts[i];
	}

	ssize_t res = writev(fd, iov, buffers);

	for (int i = 0; i < buffers; ++i) {
	(*env)->ReleasePrimitiveArrayCritical(env, targets[i], iov[i].iov_base, 0);
	}

	return (jint) (res == -1 ? -errno : res);
	}

	JNIEXPORT jint JNICALL Java_io_netty_channel_android_JNI_dg(JNIEnv *env, jclass type,
	jobject b1, jobject b2, jobject b3, jobject b4, jobject b5,
	jint buffers,
	jint o1, jint o2, jint o3, jint o4, jint o5,
	jint c1, jint c2, jint c3, jint c4, jint c5,
	jint fd) {

	struct iovec* iov = alloca(sizeof(struct iovec) * buffers);

	const jobject targets[] = { b1, b2, b3, b4, b5 };
	const jint offsets[] = { o1, o2, o3, o4, o5 };
	const jint counts[] = { c1, c2, c3, c4, c5 };

	for (int i = 0; i < buffers; ++i) {
	char* base = (*env)->GetDirectBufferAddress(env, targets[i]);
	if (base == NULL) {
	return ERR_NO_DIRECT;
	}

	iov[i].iov_base = base + offsets[i];
	iov[i].iov_len = (__kernel_size_t) counts[i];
	}

	ssize_t res = (jint) readv(fd, iov, buffers);

	return (jint) (res == -1 ? -errno : res);
	}

	JNIEXPORT jint JNICALL Java_io_netty_channel_android_JNI_hg(JNIEnv *env, jclass type,
	jbyteArray b1_, jbyteArray b2_, jbyteArray b3_, jbyteArray b4_, jbyteArray b5_,
	jint buffers,
	jint o1, jint o2, jint o3, jint o4, jint o5,
	jint c1, jint c2, jint c3, jint c4, jint c5,
	jint fd) {

	struct iovec* iov = alloca(sizeof(struct iovec) * buffers);

	const jobject targets[] = { b1_, b2_, b3_, b4_, b5_ };
	const jint offsets[] = { o1, o2, o3, o4, o5 };
	const jint counts[] = { c1, c2, c3, c4, c5 };

	for (int i = 0; i < buffers; ++i) {
	char* ptr = (*env)->GetPrimitiveArrayCritical(env, targets[i], NULL);

	iov[i].iov_base = ptr + offsets[i];
	iov[i].iov_len = (__kernel_size_t) counts[i];
	}

	ssize_t res = readv(fd, iov, buffers);

	for (int i = 0; i < buffers; ++i) {
	(*env)->ReleasePrimitiveArrayCritical(env, targets[i], iov[i].iov_base, 0);
	}

	return (jint) (res == -1 ? -errno : res);
	}

	package io.netty.channel.android;

	import android.support.annotation.NonNull;

	import java.nio.ByteBuffer;
	import java.nio.channels.GatheringByteChannel;
	import java.nio.channels.ScatteringByteChannel;

	final class FdNioChannel implements ScatteringByteChannel, GatheringByteChannel {
	private final int fd;

	FdNioChannel(int fd) {
	this.fd = fd;
	}

	private int heapScatter(@NonNull ByteBuffer[] srcs, int offset, int length) throws java.io.IOException {
	byte[] a1, a2, a3 = null, a4 = null, a5 = null;
	int o1, o2, o3 = 0, o4 = 0, o5 = 0;
	int c1, c2, c3 = 0, c4 = 0, c5 = 0;

	switch (length) {
	default:
	length = 5;
	ByteBuffer b5 = srcs[offset + 4];
	a5 = b5.array();
	o5 = b5.position() + b5.arrayOffset();
	c5 = b5.remaining();
	case 4:
	ByteBuffer b4 = srcs[offset + 3];
	a4 = b4.array();
	o4 = b4.position() + b4.arrayOffset();
	c4 = b4.remaining();
	case 3:
	ByteBuffer b3 = srcs[offset + 2];
	a3 = b3.array();
	o3 = b3.position() + b3.arrayOffset();
	c3 = b3.remaining();
	case 2:
	ByteBuffer b2 = srcs[offset + 1];
	a2 = b2.array();
	o2 = b2.position() + b2.arrayOffset();
	c2 = b2.remaining();
	ByteBuffer b1 = srcs[offset];
	a1 = b1.array();
	o1 = b1.position() + b1.arrayOffset();
	c1 = b1.remaining();
	}

	return JNI.hs(a1, a2, a3, a4, a5, length, o1, o2, o3, o4, o5, c1, c2, c3, c4, c5, fd);
	}

	private int directScatter(@NonNull ByteBuffer[] srcs, int offset, int length) throws java.io.IOException {
	ByteBuffer b1, b2, b3 = null, b4 = null, b5 = null;
	int o1, o2, o3 = 0, o4 = 0, o5 = 0;
	int c1, c2, c3 = 0, c4 = 0, c5 = 0;

	switch (length) {
	default:
	length = 5;
	b5 = srcs[offset + 4];
	o5 = b5.position();
	c5 = b5.remaining();
	case 4:
	b4 = srcs[offset + 3];
	o4 = b4.position();
	c4 = b4.remaining();
	case 3:
	b3 = srcs[offset + 2];
	o3 = b3.position();
	c3 = b3.remaining();
	case 2:
	b2 = srcs[offset + 1];
	o2 = b2.position();
	c2 = b2.remaining();
	b1 = srcs[offset];
	o1 = b1.position();
	c1 = b1.remaining();
	}

	return JNI.ds(b1, b2, b3, b4, b5, length, o1, o2, o3, o4, o5, c1, c2, c3, c4, c5, fd);
	}

	private int heapGather(@NonNull ByteBuffer[] srcs, int offset, int length) throws java.io.IOException {
	byte[] a1, a2, a3 = null, a4 = null, a5 = null;
	int o1, o2, o3 = 0, o4 = 0, o5 = 0;
	int c1, c2, c3 = 0, c4 = 0, c5 = 0;

	switch (length) {
	default:
	length = 5;
	ByteBuffer b5 = srcs[offset + 4];
	a5 = b5.array();
	o5 = b5.position() + b5.arrayOffset();
	c5 = b5.remaining();
	case 4:
	ByteBuffer b4 = srcs[offset + 3];
	a4 = b4.array();
	o4 = b4.position() + b4.arrayOffset();
	c4 = b4.remaining();
	case 3:
	ByteBuffer b3 = srcs[offset + 2];
	a3 = b3.array();
	o3 = b3.position() + b3.arrayOffset();
	c3 = b3.remaining();
	case 2:
	ByteBuffer b2 = srcs[offset + 1];
	a2 = b2.array();
	o2 = b2.position() + b2.arrayOffset();
	c2 = b2.remaining();
	ByteBuffer b1 = srcs[offset];
	a1 = b1.array();
	o1 = b1.position() + b1.arrayOffset();
	c1 = b1.remaining();
	}

	return JNI.hg(a1, a2, a3, a4, a5, length, o1, o2, o3, o4, o5, c1, c2, c3, c4, c5, fd);
	}

	private int directGather(@NonNull ByteBuffer[] srcs, int offset, int length) throws java.io.IOException {
	ByteBuffer b1, b2, b3 = null, b4 = null, b5 = null;
	int o1, o2, o3 = 0, o4 = 0, o5 = 0;
	int c1, c2, c3 = 0, c4 = 0, c5 = 0;

	switch (length) {
	default:
	length = 5;
	b5 = srcs[offset + 4];
	o5 = b5.position();
	c5 = b5.remaining();
	case 4:
	b4 = srcs[offset + 3];
	o4 = b4.position();
	c4 = b4.remaining();
	case 3:
	b3 = srcs[offset + 2];
	o3 = b3.position();
	c3 = b3.remaining();
	case 2:
	b2 = srcs[offset + 1];
	o2 = b2.position();
	c2 = b2.remaining();
	b1 = srcs[offset];
	o1 = b1.position();
	c1 = b1.remaining();
	}

	return JNI.dg(b1, b2, b3, b4, b5, length, o1, o2, o3, o4, o5, c1, c2, c3, c4, c5, fd);
	}

	@Override
	public long write(@NonNull ByteBuffer[] srcs, int offset, int length) throws java.io.IOException {
	switch (length) {
	default:
	int total = srcs[offset].isDirect()
	? directScatter(srcs, offset, length)
	: heapScatter(srcs, offset, length);

	Utils.checkErrno(total);

	int written = total;

	for (int i = offset; i < offset + length; ++i) {
	ByteBuffer b = srcs[i];

	int remaining = b.remaining();

	if (remaining >= written) {
	b.position(b.position() + written);

	break;
	} else {
	b.position(b.limit());

	written -= remaining;
	}
	}

	return total;
	case 1:
	return write(srcs[offset]);
	case 0:
	return 0;
	}
	}

	@Override
	public long read(@NonNull ByteBuffer[] dsts, int offset, int length) throws java.io.IOException {
	switch (length) {
	default:
	int total = dsts[offset].isDirect()
	? directGather(dsts, offset, length)
	: heapGather(dsts, offset, length);

	Utils.checkErrno(total);

	int read = total;

	for (int i = offset; i < offset + length; ++i) {
	ByteBuffer b = dsts[i];

	int remaining = b.remaining();

	if (remaining >= read) {
	b.position(b.position() + read);

	break;
	} else {
	b.position(b.limit());

	read -= remaining;
	}
	}

	return total;
	case 1:
	return read(dsts[offset]);
	case 0:
	return 0;
	}
	}

	@Override
	public long write(@NonNull ByteBuffer[] srcs) throws java.io.IOException {
	return write(srcs, 0, srcs.length);
	}

	@Override
	public long read(@NonNull ByteBuffer[] dsts) throws java.io.IOException {
	return write(dsts, 0, dsts.length);
	}

	@Override
	public int write(@NonNull ByteBuffer src) throws java.io.IOException {
	int written = src.isDirect() ? writeDirect(src) : writeHeap(src);

	Utils.checkErrno(written);

	src.position(src.position() + written);

	return written;
	}

	@Override
	public int read(ByteBuffer dst) throws java.io.IOException {
	int read = dst.isDirect() ? readDirect(dst) : readHeap(dst);

	Utils.checkErrno(read);

	dst.position(dst.position() + read);

	return read;
	}

	private int writeDirect(ByteBuffer direct) throws IOException {
	return JNI.dw(direct, direct.position(), direct.remaining(), fd);
	}

	private int writeHeap(ByteBuffer heap) throws IOException {
	return JNI.hw(heap.array(), heap.position() + heap.arrayOffset(), heap.remaining(), fd);
	}

	private int readDirect(ByteBuffer direct) throws IOException {
	return JNI.dr(direct, direct.position(), direct.remaining(), fd);
	}

	private int readHeap(ByteBuffer heap) throws IOException {
	return JNI.hr(heap.array(), heap.position() + heap.arrayOffset(), heap.remaining(), fd);
	}

	@Override
	public boolean isOpen() {
	return true;
	}

	@Override
	public void close() {
	}
	}