Merge "libusbhost: Remove global data to allow multiple instances in the same process."
diff --git a/fastboot/usb_osx.c b/fastboot/usb_osx.c
index 0b0512d..9488687 100644
--- a/fastboot/usb_osx.c
+++ b/fastboot/usb_osx.c
@@ -64,7 +64,7 @@
 
 /** Try out all the interfaces and see if there's a match. Returns 0 on
  * success, -1 on failure. */
-static int try_interfaces(IOUSBDeviceInterface **dev, usb_handle *handle) {
+static int try_interfaces(IOUSBDeviceInterface182 **dev, usb_handle *handle) {
     IOReturn kr;
     IOUSBFindInterfaceRequest request;
     io_iterator_t iterator;
@@ -515,8 +515,29 @@
         return -1;
     }
 
+#if 0
     result = (*h->interface)->WritePipe(
             h->interface, h->bulkOut, (void *)data, len);
+#else
+    /* Attempt to work around crashes in the USB driver that may be caused
+     * by trying to write too much data at once.  The kernel IOCopyMapper
+     * panics if a single iovmAlloc needs more than half of its mapper pages.
+     */
+    const int maxLenToSend = 1048576; // 1 MiB
+    int lenRemaining = len;
+    result = 0;
+    while (lenRemaining > 0) {
+        int lenToSend = lenRemaining > maxLenToSend
+            ? maxLenToSend : lenRemaining;
+
+        result = (*h->interface)->WritePipe(
+                h->interface, h->bulkOut, (void *)data, lenToSend);
+        if (result != 0) break;
+
+        lenRemaining -= lenToSend;
+        data = (const char*)data + lenToSend;
+    }
+#endif
 
     #if 0
     if ((result == 0) && (h->zero_mask)) {
diff --git a/include/arch/linux-arm/AndroidConfig.h b/include/arch/linux-arm/AndroidConfig.h
index f51ddb1..81f077f 100644
--- a/include/arch/linux-arm/AndroidConfig.h
+++ b/include/arch/linux-arm/AndroidConfig.h
@@ -199,7 +199,9 @@
 /*
  * Add any extra platform-specific defines here.
  */
+#ifndef __linux__
 #define __linux__
+#endif
 
 /*
  * Define if we have <malloc.h> header
diff --git a/include/cutils/atomic-inline.h b/include/cutils/atomic-inline.h
new file mode 100644
index 0000000..4f5ddf7
--- /dev/null
+++ b/include/cutils/atomic-inline.h
@@ -0,0 +1,101 @@
+/*
+ * Copyright (C) 2010 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef ANDROID_CUTILS_ATOMIC_INLINE_H
+#define ANDROID_CUTILS_ATOMIC_INLINE_H
+
+/*
+ * Inline declarations and macros for some special-purpose atomic
+ * operations.  These are intended for rare circumstances where a
+ * memory barrier needs to be issued inline rather than as a function
+ * call.
+ *
+ * Most code should not use these.
+ *
+ * Anything that does include this file must set ANDROID_SMP to either
+ * 0 or 1, indicating compilation for UP or SMP, respectively.
+ */
+
+#if !defined(ANDROID_SMP)
+# error "Must define ANDROID_SMP before including atomic-inline.h"
+#endif
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/*
+ * Define the full memory barrier for an SMP system.  This is
+ * platform-specific.
+ */
+
+#ifdef __arm__
+#include <machine/cpu-features.h>
+
+/*
+ * For ARMv6K we need to issue a specific MCR instead of the DMB, since
+ * that wasn't added until v7.  For anything older, SMP isn't relevant.
+ * Since we don't have an ARMv6K to test with, we're not going to deal
+ * with that now.
+ *
+ * The DMB instruction is found in the ARM and Thumb2 instruction sets.
+ * This will fail on plain 16-bit Thumb.
+ */
+#if defined(__ARM_HAVE_DMB)
+# define __android_membar_full_smp() \
+    do { __asm__ __volatile__ ("dmb" ::: "memory"); } while (0)
+#else
+# define __android_membar_full_smp()  ARM_SMP_defined_but_no_DMB()
+#endif
+
+#elif defined(__i386__) || defined(__x86_64__)
+/*
+ * For recent x86, we can use the SSE2 mfence instruction.
+ */
+# define __android_membar_full_smp() \
+    do { __asm__ __volatile__ ("mfence" ::: "memory"); } while (0)
+
+#else
+/*
+ * Implementation not defined for this platform.  Hopefully we're building
+ * in uniprocessor mode.
+ */
+# define __android_membar_full_smp()  SMP_barrier_not_defined_for_platform()
+#endif
+
+
+/*
+ * Full barrier.  On uniprocessors this is just a compiler reorder barrier,
+ * which ensures that the statements appearing above the barrier in the C/C++
+ * code will be issued after the statements appearing below the barrier.
+ *
+ * For SMP this also includes a memory barrier instruction.  On an ARM
+ * CPU this means that the current core will flush pending writes, wait
+ * for pending reads to complete, and discard any cached reads that could
+ * be stale.  Other CPUs may do less, but the end result is equivalent.
+ */
+#if ANDROID_SMP != 0
+# define android_membar_full() __android_membar_full_smp()
+#else
+# define android_membar_full() \
+    do { __asm__ __volatile__ ("" ::: "memory"); } while (0)
+#endif
+
+#ifdef __cplusplus
+} // extern "C"
+#endif
+
+#endif // ANDROID_CUTILS_ATOMIC_INLINE_H
diff --git a/include/cutils/atomic.h b/include/cutils/atomic.h
index 5694d66..8e12902 100644
--- a/include/cutils/atomic.h
+++ b/include/cutils/atomic.h
@@ -25,10 +25,8 @@
 #endif
 
 /*
- * NOTE: memory shared between threads is synchronized by all atomic operations
- * below, this means that no explicit memory barrier is required: all reads or 
- * writes issued before android_atomic_* operations are guaranteed to complete
- * before the atomic operation takes place.
+ * Unless otherwise noted, the operations below perform a full fence before
+ * the atomic operation on SMP systems ("release" semantics).
  */
 
 void android_atomic_write(int32_t value, volatile int32_t* addr);
@@ -37,7 +35,6 @@
  * all these atomic operations return the previous value
  */
 
-
 int32_t android_atomic_inc(volatile int32_t* addr);
 int32_t android_atomic_dec(volatile int32_t* addr);
 
@@ -48,30 +45,32 @@
 int32_t android_atomic_swap(int32_t value, volatile int32_t* addr);
 
 /*
- * NOTE: Two "quasiatomic" operations on the exact same memory address
- * are guaranteed to operate atomically with respect to each other,
- * but no guarantees are made about quasiatomic operations mixed with
- * non-quasiatomic operations on the same address, nor about
- * quasiatomic operations that are performed on partially-overlapping
- * memory.
+ * cmpxchg returns zero if the new value was successfully written.  This
+ * will only happen when *addr == oldvalue.
+ *
+ * (The return value is inverted from implementations on other platforms, but
+ * matches the ARM ldrex/strex sematics.  Note also this is a compare-and-set
+ * operation, not a compare-and-exchange operation, since we don't return
+ * the original value.)
  */
-
-int64_t android_quasiatomic_swap_64(int64_t value, volatile int64_t* addr);
-int64_t android_quasiatomic_read_64(volatile int64_t* addr);
-    
-/*
- * cmpxchg return a non zero value if the exchange was NOT performed,
- * in other words if oldvalue != *addr
- */
-
 int android_atomic_cmpxchg(int32_t oldvalue, int32_t newvalue,
         volatile int32_t* addr);
 
-int android_quasiatomic_cmpxchg_64(int64_t oldvalue, int64_t newvalue,
-        volatile int64_t* addr);
+/*
+ * Same basic operation as android_atomic_cmpxchg, but with "acquire"
+ * semantics.  The memory barrier, if required, is performed after the
+ * new value is stored.  Useful for acquiring a spin lock.
+ */
+int android_atomic_acquire_cmpxchg(int32_t oldvalue, int32_t newvalue,
+        volatile int32_t* addr);
 
+/*
+ * Perform an atomic store with "release" semantics.  The memory barrier,
+ * if required, is performed before the store instruction.  Useful for
+ * releasing a spin lock.
+ */
+#define android_atomic_release_store android_atomic_write
 
-    
 #ifdef __cplusplus
 } // extern "C"
 #endif
diff --git a/libcutils/Android.mk b/libcutils/Android.mk
index 4c45cc9..5b05a1e 100644
--- a/libcutils/Android.mk
+++ b/libcutils/Android.mk
@@ -16,6 +16,13 @@
 LOCAL_PATH := $(my-dir)
 include $(CLEAR_VARS)
 
+ifeq ($(TARGET_CPU_SMP),true)
+    targetSmpFlag := -DANDROID_SMP=1
+else
+    targetSmpFlag := -DANDROID_SMP=0
+endif
+hostSmpFlag := -DANDROID_SMP=0
+
 commonSources := \
 	array.c \
 	hashmap.c \
@@ -80,6 +87,7 @@
 LOCAL_SRC_FILES := $(commonSources) $(commonHostSources)
 LOCAL_LDLIBS := -lpthread
 LOCAL_STATIC_LIBRARIES := liblog
+LOCAL_CFLAGS += $(hostSmpFlag)
 include $(BUILD_HOST_STATIC_LIBRARY)
 
 
@@ -92,6 +100,7 @@
 LOCAL_SRC_FILES := $(commonSources) $(commonHostSources) memory.c dlmalloc_stubs.c
 LOCAL_LDLIBS := -lpthread
 LOCAL_SHARED_LIBRARIES := liblog
+LOCAL_CFLAGS += $(targetSmpFlag)
 include $(BUILD_SHARED_LIBRARY)
 
 else #!sim
@@ -114,12 +123,14 @@
 
 LOCAL_C_INCLUDES := $(KERNEL_HEADERS)
 LOCAL_STATIC_LIBRARIES := liblog
+LOCAL_CFLAGS += $(targetSmpFlag)
 include $(BUILD_STATIC_LIBRARY)
 
 include $(CLEAR_VARS)
 LOCAL_MODULE := libcutils
 LOCAL_WHOLE_STATIC_LIBRARIES := libcutils
 LOCAL_SHARED_LIBRARIES := liblog
+LOCAL_CFLAGS += $(targetSmpFlag)
 include $(BUILD_SHARED_LIBRARY)
 
 endif #!sim
diff --git a/libcutils/atomic-android-arm.S b/libcutils/atomic-android-arm.S
index 1dd2363..f918990 100644
--- a/libcutils/atomic-android-arm.S
+++ b/libcutils/atomic-android-arm.S
@@ -14,6 +14,8 @@
  * limitations under the License.
  */
 
+/* TODO: insert memory barriers on SMP */
+
 #include <machine/cpu-features.h>
 
 /*
@@ -43,6 +45,8 @@
 	
 	.global android_atomic_cmpxchg
 	.type android_atomic_cmpxchg, %function
+	.global android_atomic_acquire_cmpxchg
+	.type android_atomic_acquire_cmpxchg, %function
 
 /*
  * ----------------------------------------------------------------------------
@@ -237,7 +241,7 @@
 
 /* replaced swp instruction with ldrex/strex for ARMv6 & ARMv7 */
 android_atomic_swap:
-#if defined (_ARM_HAVE_LDREX_STREX)
+#if defined (__ARM_HAVE_LDREX_STREX)
 1:  ldrex   r2, [r1]
     strex   r3, r0, [r1]
     teq     r3, #0
@@ -256,6 +260,7 @@
  * output: r0 = 0 (xchg done) or non-zero (xchg not done)
  */
 
+android_atomic_acquire_cmpxchg:
 android_atomic_cmpxchg:
     .fnstart
     .save {r4, lr}
@@ -282,10 +287,3 @@
     bx      lr
     .fnend
 
-/*
- * ----------------------------------------------------------------------------
- * android_atomic_cmpxchg_64
- * input: r0-r1=oldvalue, r2-r3=newvalue, arg4 (on stack)=address
- * output: r0 = 0 (xchg done) or non-zero (xchg not done)
- */
-/* TODO: NEED IMPLEMENTATION FOR THIS ARCHITECTURE */
diff --git a/libcutils/atomic-android-sh.c b/libcutils/atomic-android-sh.c
index acbea97..d95b02b 100644
--- a/libcutils/atomic-android-sh.c
+++ b/libcutils/atomic-android-sh.c
@@ -118,42 +118,8 @@
     return result;
 }
 
-int64_t android_quasiatomic_swap_64(int64_t value, volatile int64_t* addr) {
-    int64_t oldValue;
-    pthread_mutex_t*  lock = SWAP_LOCK(addr);
-
-    pthread_mutex_lock(lock);
-
-    oldValue = *addr;
-    *addr    = value;
-
-    pthread_mutex_unlock(lock);
-    return oldValue;
+int android_atomic_acquire_cmpxchg(int32_t oldvalue, int32_t newvalue,
+                           volatile int32_t* addr) {
+    return android_atomic_cmpxchg(oldValue, newValue, addr);
 }
 
-int android_quasiatomic_cmpxchg_64(int64_t oldvalue, int64_t newvalue,
-        volatile int64_t* addr) {
-    int result;
-    pthread_mutex_t*  lock = SWAP_LOCK(addr);
-
-    pthread_mutex_lock(lock);
-
-    if (*addr == oldvalue) {
-        *addr  = newvalue;
-        result = 0;
-    } else {
-        result = 1;
-    }
-    pthread_mutex_unlock(lock);
-    return result;
-}
-
-int64_t android_quasiatomic_read_64(volatile int64_t* addr) {
-    int64_t result;
-    pthread_mutex_t*  lock = SWAP_LOCK(addr);
-
-    pthread_mutex_lock(lock);
-    result = *addr;
-    pthread_mutex_unlock(lock);
-    return result;
-}
diff --git a/libcutils/atomic.c b/libcutils/atomic.c
index 41faaa2..d818906 100644
--- a/libcutils/atomic.c
+++ b/libcutils/atomic.c
@@ -15,6 +15,7 @@
  */
 
 #include <cutils/atomic.h>
+#include <cutils/atomic-inline.h>
 #ifdef HAVE_WIN32_THREADS
 #include <windows.h>
 #else
@@ -70,40 +71,19 @@
 }
 
 int android_atomic_cmpxchg(int32_t oldvalue, int32_t newvalue, volatile int32_t* addr) {
+    /* OS X CAS returns zero on failure; invert to return zero on success */
     return OSAtomicCompareAndSwap32Barrier(oldvalue, newvalue, (int32_t*)addr) == 0;
 }
 
-#if defined(__ppc__)        \
-    || defined(__PPC__)     \
-    || defined(__powerpc__) \
-    || defined(__powerpc)   \
-    || defined(__POWERPC__) \
-    || defined(_M_PPC)      \
-    || defined(__PPC)
-#define NEED_QUASIATOMICS 1
-#else
-
-int android_quasiatomic_cmpxchg_64(int64_t oldvalue, int64_t newvalue,
-        volatile int64_t* addr) {
-    return OSAtomicCompareAndSwap64Barrier(oldvalue, newvalue,
-            (int64_t*)addr) == 0;
+int android_atomic_acquire_cmpxchg(int32_t oldvalue, int32_t newvalue,
+        volatile int32_t* addr) {
+    int result = (OSAtomicCompareAndSwap32(oldvalue, newvalue, (int32_t*)addr) == 0);
+    if (!result) {
+        /* success, perform barrier */
+        OSMemoryBarrier();
+    }
 }
 
-int64_t android_quasiatomic_swap_64(int64_t value, volatile int64_t* addr) {
-    int64_t oldValue;
-    do {
-        oldValue = *addr;
-    } while (android_quasiatomic_cmpxchg_64(oldValue, value, addr));
-    return oldValue;
-}
-
-int64_t android_quasiatomic_read_64(volatile int64_t* addr) {
-    return OSAtomicAdd64Barrier(0, addr);
-}    
-
-#endif
-
-
 /*****************************************************************************/
 #elif defined(__i386__) || defined(__x86_64__)
 
@@ -163,6 +143,7 @@
 }
 
 int android_atomic_cmpxchg(int32_t oldvalue, int32_t newvalue, volatile int32_t* addr) {
+    android_membar_full();
     int xchg;
     asm volatile
     (
@@ -175,75 +156,25 @@
     return xchg;
 }
 
-#define NEED_QUASIATOMICS 1
+int android_atomic_acquire_cmpxchg(int32_t oldvalue, int32_t newvalue,
+        volatile int32_t* addr) {
+    int xchg;
+    asm volatile
+    (
+    "   lock; cmpxchg %%ecx, (%%edx);"
+    "   setne %%al;"
+    "   andl $1, %%eax"
+    : "=a" (xchg)
+    : "a" (oldvalue), "c" (newvalue), "d" (addr)
+    );
+    android_membar_full();
+    return xchg;
+}
+
 
 /*****************************************************************************/
 #elif __arm__
-// Most of the implementation is in atomic-android-arm.s.
-
-// on the device, we implement the 64-bit atomic operations through
-// mutex locking. normally, this is bad because we must initialize
-// a pthread_mutex_t before being able to use it, and this means
-// having to do an initialization check on each function call, and
-// that's where really ugly things begin...
-//
-// BUT, as a special twist, we take advantage of the fact that in our
-// pthread library, a mutex is simply a volatile word whose value is always
-// initialized to 0. In other words, simply declaring a static mutex
-// object initializes it !
-//
-// another twist is that we use a small array of mutexes to dispatch
-// the contention locks from different memory addresses
-//
-
-#include <pthread.h>
-
-#define  SWAP_LOCK_COUNT  32U
-static pthread_mutex_t  _swap_locks[SWAP_LOCK_COUNT];
-
-#define  SWAP_LOCK(addr)   \
-   &_swap_locks[((unsigned)(void*)(addr) >> 3U) % SWAP_LOCK_COUNT]
-
-
-int64_t android_quasiatomic_swap_64(int64_t value, volatile int64_t* addr) {
-    int64_t oldValue;
-    pthread_mutex_t*  lock = SWAP_LOCK(addr);
-
-    pthread_mutex_lock(lock);
-
-    oldValue = *addr;
-    *addr    = value;
-
-    pthread_mutex_unlock(lock);
-    return oldValue;
-}
-
-int android_quasiatomic_cmpxchg_64(int64_t oldvalue, int64_t newvalue,
-        volatile int64_t* addr) {
-    int result;
-    pthread_mutex_t*  lock = SWAP_LOCK(addr);
-
-    pthread_mutex_lock(lock);
-
-    if (*addr == oldvalue) {
-        *addr  = newvalue;
-        result = 0;
-    } else {
-        result = 1;
-    }
-    pthread_mutex_unlock(lock);
-    return result;
-}
-
-int64_t android_quasiatomic_read_64(volatile int64_t* addr) {
-    int64_t result;
-    pthread_mutex_t*  lock = SWAP_LOCK(addr);
-
-    pthread_mutex_lock(lock);
-    result = *addr;
-    pthread_mutex_unlock(lock);
-    return result;
-}    
+// implementation for ARM is in atomic-android-arm.s.
 
 /*****************************************************************************/
 #elif __sh__
@@ -255,85 +186,3 @@
 
 #endif
 
-
-
-#if NEED_QUASIATOMICS
-
-/* Note that a spinlock is *not* a good idea in general
- * since they can introduce subtle issues. For example,
- * a real-time thread trying to acquire a spinlock already
- * acquired by another thread will never yeld, making the
- * CPU loop endlessly!
- *
- * However, this code is only used on the Linux simulator
- * so it's probably ok for us.
- *
- * The alternative is to use a pthread mutex, but
- * these must be initialized before being used, and
- * then you have the problem of lazily initializing
- * a mutex without any other synchronization primitive.
- */
-
-/* global spinlock for all 64-bit quasiatomic operations */
-static int32_t quasiatomic_spinlock = 0;
-
-int android_quasiatomic_cmpxchg_64(int64_t oldvalue, int64_t newvalue,
-        volatile int64_t* addr) {
-    int result;
-    
-    while (android_atomic_cmpxchg(0, 1, &quasiatomic_spinlock)) {
-#ifdef HAVE_WIN32_THREADS
-        Sleep(0);
-#else        
-        sched_yield();
-#endif        
-    }
-
-    if (*addr == oldvalue) {
-        *addr = newvalue;
-        result = 0;
-    } else {
-        result = 1;
-    }
-
-    android_atomic_swap(0, &quasiatomic_spinlock);
-
-    return result;
-}
-
-int64_t android_quasiatomic_read_64(volatile int64_t* addr) {
-    int64_t result;
-    
-    while (android_atomic_cmpxchg(0, 1, &quasiatomic_spinlock)) {
-#ifdef HAVE_WIN32_THREADS
-        Sleep(0);
-#else
-        sched_yield();
-#endif
-    }
-
-    result = *addr;
-    android_atomic_swap(0, &quasiatomic_spinlock);
-
-    return result;
-}
-
-int64_t android_quasiatomic_swap_64(int64_t value, volatile int64_t* addr) {
-    int64_t result;
-    
-    while (android_atomic_cmpxchg(0, 1, &quasiatomic_spinlock)) {
-#ifdef HAVE_WIN32_THREADS
-        Sleep(0);
-#else
-        sched_yield();
-#endif
-    }
-
-    result = *addr;
-    *addr = value;
-    android_atomic_swap(0, &quasiatomic_spinlock);
-
-    return result;
-}
-
-#endif
diff --git a/liblinenoise/Android.mk b/liblinenoise/Android.mk
new file mode 100644
index 0000000..b32a5f1
--- /dev/null
+++ b/liblinenoise/Android.mk
@@ -0,0 +1,12 @@
+LOCAL_PATH:= $(call my-dir)
+include $(CLEAR_VARS)
+
+# Static library
+# ========================================================
+
+include $(CLEAR_VARS)
+LOCAL_MODULE:= liblinenoise
+LOCAL_SRC_FILES := linenoise.c
+
+
+include $(BUILD_STATIC_LIBRARY)
diff --git a/liblinenoise/MODULE_LICENSE_BSD_LIKE b/liblinenoise/MODULE_LICENSE_BSD_LIKE
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/liblinenoise/MODULE_LICENSE_BSD_LIKE
diff --git a/liblinenoise/NOTICE b/liblinenoise/NOTICE
new file mode 100644
index 0000000..f61419e
--- /dev/null
+++ b/liblinenoise/NOTICE
@@ -0,0 +1,28 @@
+Copyright (c) 2010, Salvatore Sanfilippo <antirez at gmail dot com>
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+  * Redistributions of source code must retain the above copyright notice,
+    this list of conditions and the following disclaimer.
+    
+  * Redistributions in binary form must reproduce the above copyright
+    notice, this list of conditions and the following disclaimer in the
+    documentation and/or other materials provided with the distribution.
+    
+  * Neither the name of Redis nor the names of its contributors may be used
+    to endorse or promote products derived from this software without
+    specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGE.
\ No newline at end of file
diff --git a/liblinenoise/linenoise.c b/liblinenoise/linenoise.c
new file mode 100644
index 0000000..ab57ae6
--- /dev/null
+++ b/liblinenoise/linenoise.c
@@ -0,0 +1,435 @@
+/* linenoise.c -- guerrilla line editing library against the idea that a
+ * line editing lib needs to be 20,000 lines of C code.
+ *
+ * You can find the latest source code at:
+ * 
+ *   http://github.com/antirez/linenoise
+ *
+ * Does a number of crazy assumptions that happen to be true in 99.9999% of
+ * the 2010 UNIX computers around.
+ *
+ * Copyright (c) 2010, Salvatore Sanfilippo <antirez at gmail dot com>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ *   * Redistributions of source code must retain the above copyright notice,
+ *     this list of conditions and the following disclaimer.
+ *   * Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in the
+ *     documentation and/or other materials provided with the distribution.
+ *   * Neither the name of Redis nor the names of its contributors may be used
+ *     to endorse or promote products derived from this software without
+ *     specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ * References:
+ * - http://invisible-island.net/xterm/ctlseqs/ctlseqs.html
+ * - http://www.3waylabs.com/nw/WWW/products/wizcon/vt220.html
+ *
+ * Todo list:
+ * - Switch to gets() if $TERM is something we can't support.
+ * - Filter bogus Ctrl+<char> combinations.
+ * - Win32 support
+ *
+ * Bloat:
+ * - Completion?
+ * - History search like Ctrl+r in readline?
+ *
+ * List of escape sequences used by this program, we do everything just
+ * with three sequences. In order to be so cheap we may have some
+ * flickering effect with some slow terminal, but the lesser sequences
+ * the more compatible.
+ *
+ * CHA (Cursor Horizontal Absolute)
+ *    Sequence: ESC [ n G
+ *    Effect: moves cursor to column n
+ *
+ * EL (Erase Line)
+ *    Sequence: ESC [ n K
+ *    Effect: if n is 0 or missing, clear from cursor to end of line
+ *    Effect: if n is 1, clear from beginning of line to cursor
+ *    Effect: if n is 2, clear entire line
+ *
+ * CUF (CUrsor Forward)
+ *    Sequence: ESC [ n C
+ *    Effect: moves cursor forward of n chars
+ * 
+ */
+
+#include <termios.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <errno.h>
+#include <string.h>
+#include <stdlib.h>
+#include <sys/types.h>
+#include <sys/ioctl.h>
+#include <unistd.h>
+
+#define LINENOISE_MAX_LINE 4096
+static char *unsupported_term[] = {"dumb","cons25",NULL};
+
+static struct termios orig_termios; /* in order to restore at exit */
+static int rawmode = 0; /* for atexit() function to check if restore is needed*/
+static int atexit_registered = 0; /* register atexit just 1 time */
+static int history_max_len = 100;
+static int history_len = 0;
+char **history = NULL;
+
+static void linenoiseAtExit(void);
+int linenoiseHistoryAdd(const char *line);
+
+static int isUnsupportedTerm(void) {
+    char *term = getenv("TERM");
+    int j;
+
+    if (term == NULL) return 0;
+    for (j = 0; unsupported_term[j]; j++)
+        if (!strcasecmp(term,unsupported_term[j])) return 1;
+    return 0;
+}
+
+static void freeHistory(void) {
+    if (history) {
+        int j;
+
+        for (j = 0; j < history_len; j++)
+            free(history[j]);
+        free(history);
+    }
+}
+
+static int enableRawMode(int fd) {
+    struct termios raw;
+
+    if (!isatty(STDIN_FILENO)) goto fatal;
+    if (!atexit_registered) {
+        atexit(linenoiseAtExit);
+        atexit_registered = 1;
+    }
+    if (tcgetattr(fd,&orig_termios) == -1) goto fatal;
+
+    raw = orig_termios;  /* modify the original mode */
+    /* input modes: no break, no CR to NL, no parity check, no strip char,
+     * no start/stop output control. */
+    raw.c_iflag &= ~(BRKINT | ICRNL | INPCK | ISTRIP | IXON);
+    /* output modes - disable post processing */
+    raw.c_oflag &= ~(OPOST);
+    /* control modes - set 8 bit chars */
+    raw.c_cflag |= (CS8);
+    /* local modes - choing off, canonical off, no extended functions,
+     * no signal chars (^Z,^C) */
+    raw.c_lflag &= ~(ECHO | ICANON | IEXTEN | ISIG);
+    /* control chars - set return condition: min number of bytes and timer.
+     * We want read to return every single byte, without timeout. */
+    raw.c_cc[VMIN] = 1; raw.c_cc[VTIME] = 0; /* 1 byte, no timer */
+
+    /* put terminal in raw mode after flushing */
+    if (tcsetattr(fd,TCSAFLUSH,&raw) < 0) goto fatal;
+    rawmode = 1;
+    return 0;
+
+fatal:
+    errno = ENOTTY;
+    return -1;
+}
+
+static void disableRawMode(int fd) {
+    /* Don't even check the return value as it's too late. */
+    if (rawmode && tcsetattr(fd,TCSAFLUSH,&orig_termios) != -1)
+        rawmode = 0;
+}
+
+/* At exit we'll try to fix the terminal to the initial conditions. */
+static void linenoiseAtExit(void) {
+    disableRawMode(STDIN_FILENO);
+    freeHistory();
+}
+
+static int getColumns(void) {
+    struct winsize ws;
+
+    if (ioctl(1, TIOCGWINSZ, &ws) == -1) return 80;
+    if (ws.ws_col == 0) {
+        return 80;
+    }
+    return ws.ws_col;
+}
+
+static void refreshLine(int fd, const char *prompt, char *buf, size_t len, size_t pos, size_t cols) {
+    char seq[64];
+    size_t plen = strlen(prompt);
+    
+    while((plen+pos) >= cols) {
+        buf++;
+        len--;
+        pos--;
+    }
+    while (plen+len > cols) {
+        len--;
+    }
+
+    /* Cursor to left edge */
+    snprintf(seq,64,"\x1b[0G");
+    if (write(fd,seq,strlen(seq)) == -1) return;
+    /* Write the prompt and the current buffer content */
+    if (write(fd,prompt,strlen(prompt)) == -1) return;
+    if (write(fd,buf,len) == -1) return;
+    /* Erase to right */
+    snprintf(seq,64,"\x1b[0K");
+    if (write(fd,seq,strlen(seq)) == -1) return;
+    /* Move cursor to original position. */
+    snprintf(seq,64,"\x1b[0G\x1b[%dC", (int)(pos+plen));
+    if (write(fd,seq,strlen(seq)) == -1) return;
+}
+
+static int linenoisePrompt(int fd, char *buf, size_t buflen, const char *prompt) {
+    size_t plen = strlen(prompt);
+    size_t pos = 0;
+    size_t len = 0;
+    size_t cols = getColumns();
+    int history_index = 0;
+
+    buf[0] = '\0';
+    buflen--; /* Make sure there is always space for the nulterm */
+
+    /* The latest history entry is always our current buffer, that
+     * initially is just an empty string. */
+    linenoiseHistoryAdd("");
+    
+    if (write(fd,prompt,plen) == -1) return -1;
+    while(1) {
+        char c;
+        int nread;
+        char seq[2];
+
+        nread = read(fd,&c,1);
+        if (nread <= 0) return len;
+        switch(c) {
+        case 10:    /* line feed. */
+        case 13:    /* enter */
+            history_len--;
+            return len;
+        case 4:     /* ctrl-d */
+            history_len--;
+            return (len == 0) ? -1 : (int)len;
+        case 3:     /* ctrl-c */
+            errno = EAGAIN;
+            return -1;
+        case 127:   /* backspace */
+        case 8:     /* ctrl-h */
+            if (pos > 0 && len > 0) {
+                memmove(buf+pos-1,buf+pos,len-pos);
+                pos--;
+                len--;
+                buf[len] = '\0';
+                refreshLine(fd,prompt,buf,len,pos,cols);
+            }
+            break;
+        case 20:    /* ctrl-t */
+            if (pos > 0 && pos < len) {
+                int aux = buf[pos-1];
+                buf[pos-1] = buf[pos];
+                buf[pos] = aux;
+                if (pos != len-1) pos++;
+                refreshLine(fd,prompt,buf,len,pos,cols);
+            }
+            break;
+        case 2:     /* ctrl-b */
+            goto left_arrow;
+        case 6:     /* ctrl-f */
+            goto right_arrow;
+        case 16:    /* ctrl-p */
+            seq[1] = 65;
+            goto up_down_arrow;
+        case 14:    /* ctrl-n */
+            seq[1] = 66;
+            goto up_down_arrow;
+            break;
+        case 27:    /* escape sequence */
+            if (read(fd,seq,2) == -1) break;
+            if (seq[0] == 91 && seq[1] == 68) {
+left_arrow:
+                /* left arrow */
+                if (pos > 0) {
+                    pos--;
+                    refreshLine(fd,prompt,buf,len,pos,cols);
+                }
+            } else if (seq[0] == 91 && seq[1] == 67) {
+right_arrow:
+                /* right arrow */
+                if (pos != len) {
+                    pos++;
+                    refreshLine(fd,prompt,buf,len,pos,cols);
+                }
+            } else if (seq[0] == 91 && (seq[1] == 65 || seq[1] == 66)) {
+up_down_arrow:
+                /* up and down arrow: history */
+                if (history_len > 1) {
+                    /* Update the current history entry before to
+                     * overwrite it with tne next one. */
+                    free(history[history_len-1-history_index]);
+                    history[history_len-1-history_index] = strdup(buf);
+                    /* Show the new entry */
+                    history_index += (seq[1] == 65) ? 1 : -1;
+                    if (history_index < 0) {
+                        history_index = 0;
+                        break;
+                    } else if (history_index >= history_len) {
+                        history_index = history_len-1;
+                        break;
+                    }
+                    strncpy(buf,history[history_len-1-history_index],buflen);
+                    buf[buflen] = '\0';
+                    len = pos = strlen(buf);
+                    refreshLine(fd,prompt,buf,len,pos,cols);
+                }
+            }
+            break;
+        default:
+            if (len < buflen) {
+                if (len == pos) {
+                    buf[pos] = c;
+                    pos++;
+                    len++;
+                    buf[len] = '\0';
+                    if (plen+len < cols) {
+                        /* Avoid a full update of the line in the
+                         * trivial case. */
+                        if (write(fd,&c,1) == -1) return -1;
+                    } else {
+                        refreshLine(fd,prompt,buf,len,pos,cols);
+                    }
+                } else {
+                    memmove(buf+pos+1,buf+pos,len-pos);
+                    buf[pos] = c;
+                    len++;
+                    pos++;
+                    buf[len] = '\0';
+                    refreshLine(fd,prompt,buf,len,pos,cols);
+                }
+            }
+            break;
+        case 21: /* Ctrl+u, delete the whole line. */
+            buf[0] = '\0';
+            pos = len = 0;
+            refreshLine(fd,prompt,buf,len,pos,cols);
+            break;
+        case 11: /* Ctrl+k, delete from current to end of line. */
+            buf[pos] = '\0';
+            len = pos;
+            refreshLine(fd,prompt,buf,len,pos,cols);
+            break;
+        case 1: /* Ctrl+a, go to the start of the line */
+            pos = 0;
+            refreshLine(fd,prompt,buf,len,pos,cols);
+            break;
+        case 5: /* ctrl+e, go to the end of the line */
+            pos = len;
+            refreshLine(fd,prompt,buf,len,pos,cols);
+            break;
+        }
+    }
+    return len;
+}
+
+static int linenoiseRaw(char *buf, size_t buflen, const char *prompt) {
+    int fd = STDIN_FILENO;
+    int count;
+
+    if (buflen == 0) {
+        errno = EINVAL;
+        return -1;
+    }
+    if (!isatty(STDIN_FILENO)) {
+        if (fgets(buf, buflen, stdin) == NULL) return -1;
+        count = strlen(buf);
+        if (count && buf[count-1] == '\n') {
+            count--;
+            buf[count] = '\0';
+        }
+    } else {
+        if (enableRawMode(fd) == -1) return -1;
+        count = linenoisePrompt(fd, buf, buflen, prompt);        
+        disableRawMode(fd);
+    }
+    return count;
+}
+
+char *linenoise(const char *prompt) {
+    char buf[LINENOISE_MAX_LINE];
+    int count;
+
+    if (isUnsupportedTerm()) {
+        size_t len;
+
+        printf("%s",prompt);
+        fflush(stdout);
+        if (fgets(buf,LINENOISE_MAX_LINE,stdin) == NULL) return NULL;
+        len = strlen(buf);
+        while(len && (buf[len-1] == '\n' || buf[len-1] == '\r')) {
+            len--;
+            buf[len] = '\0';
+        }
+        return strdup(buf);
+    } else {
+        count = linenoiseRaw(buf,LINENOISE_MAX_LINE,prompt);
+        if (count == -1) return NULL;
+        return strdup(buf);
+    }
+}
+
+/* Using a circular buffer is smarter, but a bit more complex to handle. */
+int linenoiseHistoryAdd(const char *line) {
+    char *linecopy;
+
+    if (history_max_len == 0) return 0;
+    if (history == 0) {
+        history = malloc(sizeof(char*)*history_max_len);
+        if (history == NULL) return 0;
+        memset(history,0,(sizeof(char*)*history_max_len));
+    }
+    linecopy = strdup(line);
+    if (!linecopy) return 0;
+    if (history_len == history_max_len) {
+        memmove(history,history+1,sizeof(char*)*(history_max_len-1));
+        history_len--;
+    }
+    history[history_len] = linecopy;
+    history_len++;
+    return 1;
+}
+
+int linenoiseHistorySetMaxLen(int len) {
+    char **new;
+
+    if (len < 1) return 0;
+    if (history) {
+        int tocopy = history_len;
+
+        new = malloc(sizeof(char*)*len);
+        if (new == NULL) return 0;
+        if (len < tocopy) tocopy = len;
+        memcpy(new,history+(history_max_len-tocopy), sizeof(char*)*tocopy);
+        free(history);
+        history = new;
+    }
+    history_max_len = len;
+    if (history_len > history_max_len)
+        history_len = history_max_len;
+    return 1;
+}
diff --git a/liblinenoise/linenoise.h b/liblinenoise/linenoise.h
new file mode 100644
index 0000000..57bf9d1
--- /dev/null
+++ b/liblinenoise/linenoise.h
@@ -0,0 +1,41 @@
+/* linenoise.h -- guerrilla line editing library against the idea that a
+ * line editing lib needs to be 20,000 lines of C code.
+ *
+ * See linenoise.c for more information.
+ *
+ * Copyright (c) 2010, Salvatore Sanfilippo <antirez at gmail dot com>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ *   * Redistributions of source code must retain the above copyright notice,
+ *     this list of conditions and the following disclaimer.
+ *   * Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in the
+ *     documentation and/or other materials provided with the distribution.
+ *   * Neither the name of Redis nor the names of its contributors may be used
+ *     to endorse or promote products derived from this software without
+ *     specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef __LINENOISE_H
+#define __LINENOISE_H
+
+char *linenoise(const char *prompt);
+int linenoiseHistoryAdd(const char *line);
+int linenoiseHistorySetMaxLen(int len);
+
+#endif /* __LINENOISE_H */
diff --git a/sh/Android.mk b/sh/Android.mk
index 09bb6ac..b5e5c38 100644
--- a/sh/Android.mk
+++ b/sh/Android.mk
@@ -31,7 +31,11 @@
 
 LOCAL_MODULE:= sh
 
-LOCAL_CFLAGS += -DSHELL
+LOCAL_CFLAGS += -DSHELL -DWITH_LINENOISE
+
+LOCAL_STATIC_LIBRARIES := liblinenoise
+
+LOCAL_C_INCLUDES += system/core/liblinenoise
 
 make_ash_files: PRIVATE_SRC_FILES := $(SRC_FILES)
 make_ash_files: PRIVATE_CFLAGS := $(LOCAL_CFLAGS)
diff --git a/sh/input.c b/sh/input.c
index a81fd7b..9377bd0 100644
--- a/sh/input.c
+++ b/sh/input.c
@@ -64,6 +64,10 @@
 #include "parser.h"
 #include "myhistedit.h"
 
+#ifdef WITH_LINENOISE
+#include "linenoise.h"
+#endif
+
 #define EOF_NLEFT -99		/* value of parsenleft when EOF pushed back */
 
 MKINIT
@@ -203,6 +207,45 @@
 
 	} else
 #endif
+#ifdef WITH_LINENOISE
+    if (parsefile->fd == 0) {
+        static char *rl_start;
+        static const char *rl_cp;
+        static int el_len;
+
+        if (rl_cp == NULL) {
+            rl_cp = rl_start = linenoise(getprompt(""));
+            if (rl_cp != NULL) {
+                el_len = strlen(rl_start);
+                if (el_len != 0) {
+                    /* Add non-blank lines to history. */
+                    linenoiseHistoryAdd(rl_start);
+                }
+                out2str("\r\n");
+                /* Client expects a newline at end of input, doesn't expect null */
+                rl_start[el_len++] = '\n';
+            }
+        }
+        if (rl_cp == NULL)
+            nr = 0;
+        else {
+            nr = el_len;
+            if (nr > BUFSIZ - 8)
+                nr = BUFSIZ - 8;
+            memcpy(buf, rl_cp, nr);
+            if (nr != el_len) {
+                el_len -= nr;
+                rl_cp += nr;
+            } else {
+                rl_cp = 0;
+                if (rl_start != NULL) {
+                    free(rl_start);
+                    rl_start = NULL;
+                }
+            }
+        }
+    } else
+#endif
 		nr = read(parsefile->fd, buf, BUFSIZ - 8);
 
 
diff --git a/sh/parser.c b/sh/parser.c
index 67de58e..d956375 100644
--- a/sh/parser.c
+++ b/sh/parser.c
@@ -1628,7 +1628,10 @@
 #ifdef WITH_HISTORY
 	if (!el)
 #endif
+#ifdef WITH_LINENOISE
+#else
 		out2str(getprompt(NULL));
+#endif
 }
 
 /*