diff --git a/README.md b/README.md
index 01fab94..dc3d44e 100644
--- a/README.md
+++ b/README.md
@@ -27,3 +27,16 @@
     # Or 64-bit device
     adb shell /data/nativetest64/recovery_unit_test/recovery_unit_test
     adb shell /data/nativetest64/recovery_component_test/recovery_component_test
+
+Running the manual tests
+------------------------
+
+`recovery-refresh` and `recovery-persist` executables exist only on systems without
+/cache partition. And we need to follow special steps to run tests for them.
+
+- Execute the test on an A/B device first. The test should fail but it will log
+  some contents to pmsg.
+
+- Reboot the device immediately and run the test again. The test should save the
+  contents of pmsg buffer into /data/misc/recovery/inject.txt. Test will pass if
+  this file has expected contents.
diff --git a/bootloader_message/bootloader_message.cpp b/bootloader_message/bootloader_message.cpp
index 59c2b2e..f6f8005 100644
--- a/bootloader_message/bootloader_message.cpp
+++ b/bootloader_message/bootloader_message.cpp
@@ -163,6 +163,19 @@
   return write_bootloader_message(boot, err);
 }
 
+bool write_reboot_bootloader(std::string* err) {
+  bootloader_message boot;
+  if (!read_bootloader_message(&boot, err)) {
+    return false;
+  }
+  if (boot.command[0] != '\0') {
+    *err = "Bootloader command pending.";
+    return false;
+  }
+  strlcpy(boot.command, "bootonce-bootloader", sizeof(boot.command));
+  return write_bootloader_message(boot, err);
+}
+
 bool read_wipe_package(std::string* package_data, size_t size, std::string* err) {
   package_data->resize(size);
   return read_misc_partition(&(*package_data)[0], size, WIPE_PACKAGE_OFFSET_IN_MISC, err);
@@ -173,6 +186,11 @@
                               WIPE_PACKAGE_OFFSET_IN_MISC, err);
 }
 
+extern "C" bool write_reboot_bootloader(void) {
+  std::string err;
+  return write_reboot_bootloader(&err);
+}
+
 extern "C" bool write_bootloader_message(const char* options) {
   std::string err;
   return write_bootloader_message({options}, &err);
diff --git a/bootloader_message/include/bootloader_message/bootloader_message.h b/bootloader_message/include/bootloader_message/bootloader_message.h
index 07ecf85..5a5dd87 100644
--- a/bootloader_message/include/bootloader_message/bootloader_message.h
+++ b/bootloader_message/include/bootloader_message/bootloader_message.h
@@ -183,6 +183,9 @@
 bool write_bootloader_message(const std::vector<std::string>& options, std::string* err);
 bool clear_bootloader_message(std::string* err);
 
+// Writes the reboot-bootloader reboot reason to the bootloader_message.
+bool write_reboot_bootloader(std::string* err);
+
 bool read_wipe_package(std::string* package_data, size_t size, std::string* err);
 bool write_wipe_package(const std::string& package_data, std::string* err);
 
@@ -192,6 +195,7 @@
 
 // C Interface.
 bool write_bootloader_message(const char* options);
+bool write_reboot_bootloader(void);
 
 #endif  // ifdef __cplusplus
 
diff --git a/minui/resources.cpp b/minui/resources.cpp
index 730b05f..455ef27 100644
--- a/minui/resources.cpp
+++ b/minui/resources.cpp
@@ -269,7 +269,7 @@
         printf("  found fps = %d\n", *fps);
     }
 
-    if (frames <= 0 || fps <= 0) {
+    if (*frames <= 0 || *fps <= 0) {
         printf("bad number of frames (%d) and/or FPS (%d)\n", *frames, *fps);
         result = -10;
         goto exit;
diff --git a/otautil/Android.mk b/otautil/Android.mk
index 3acfa53..e602f19 100644
--- a/otautil/Android.mk
+++ b/otautil/Android.mk
@@ -20,16 +20,10 @@
     DirUtil.cpp \
     ZipUtil.cpp
 
-LOCAL_C_INCLUDES := \
-    external/zlib \
-    external/safe-iop/include
-
 LOCAL_STATIC_LIBRARIES := libselinux libbase
 
 LOCAL_MODULE := libotautil
 
-LOCAL_CLANG := true
-
 LOCAL_CFLAGS += -Werror -Wall
 
 include $(BUILD_STATIC_LIBRARY)
diff --git a/otautil/SysUtil.cpp b/otautil/SysUtil.cpp
index 2936c5c..a2133b9 100644
--- a/otautil/SysUtil.cpp
+++ b/otautil/SysUtil.cpp
@@ -1,212 +1,212 @@
 /*
  * Copyright 2006 The Android Open Source Project
  *
- * System utilities.
+ * 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.
  */
-#include <assert.h>
-#include <errno.h>
-#include <fcntl.h>
-#include <limits.h>
-#include <stdbool.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <sys/mman.h>
-#include <sys/stat.h>
-#include <sys/types.h>
-#include <unistd.h>
-
-#include <android-base/logging.h>
 
 #include "SysUtil.h"
 
+#include <errno.h>
+#include <fcntl.h>
+#include <stdint.h>
+#include <sys/mman.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+
+#include <algorithm>
+#include <string>
+#include <vector>
+
+#include <android-base/file.h>
+#include <android-base/logging.h>
+#include <android-base/strings.h>
+#include <android-base/unique_fd.h>
+
 static bool sysMapFD(int fd, MemMapping* pMap) {
-    assert(pMap != NULL);
+  CHECK(pMap != nullptr);
 
-    struct stat sb;
-    if (fstat(fd, &sb) == -1) {
-        PLOG(ERROR) << "fstat(" << fd << ") failed";
-        return false;
-    }
+  struct stat sb;
+  if (fstat(fd, &sb) == -1) {
+    PLOG(ERROR) << "fstat(" << fd << ") failed";
+    return false;
+  }
 
-    void* memPtr = mmap(NULL, sb.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
-    if (memPtr == MAP_FAILED) {
-        PLOG(ERROR) << "mmap(" << sb.st_size << ", R, PRIVATE, " << fd << ", 0) failed";
-        return false;
-    }
+  void* memPtr = mmap(nullptr, sb.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
+  if (memPtr == MAP_FAILED) {
+    PLOG(ERROR) << "mmap(" << sb.st_size << ", R, PRIVATE, " << fd << ", 0) failed";
+    return false;
+  }
 
-    pMap->addr = reinterpret_cast<unsigned char*>(memPtr);
-    pMap->length = sb.st_size;
-    pMap->range_count = 1;
-    pMap->ranges = reinterpret_cast<MappedRange*>(malloc(sizeof(MappedRange)));
-    if (pMap->ranges == NULL) {
-        PLOG(ERROR) << "malloc failed";
-        munmap(memPtr, sb.st_size);
-        return false;
-    }
-    pMap->ranges[0].addr = memPtr;
-    pMap->ranges[0].length = sb.st_size;
+  pMap->addr = static_cast<unsigned char*>(memPtr);
+  pMap->length = sb.st_size;
+  pMap->ranges.push_back({ memPtr, static_cast<size_t>(sb.st_size) });
 
-    return true;
+  return true;
 }
 
-static int sysMapBlockFile(FILE* mapf, MemMapping* pMap)
-{
-    char block_dev[PATH_MAX+1];
-    size_t size;
-    unsigned int blksize;
-    size_t blocks;
-    unsigned int range_count;
-    unsigned int i;
+// A "block map" which looks like this (from uncrypt/uncrypt.cpp):
+//
+//     /dev/block/platform/msm_sdcc.1/by-name/userdata     # block device
+//     49652 4096                        # file size in bytes, block size
+//     3                                 # count of block ranges
+//     1000 1008                         # block range 0
+//     2100 2102                         # ... block range 1
+//     30 33                             # ... block range 2
+//
+// Each block range represents a half-open interval; the line "30 33"
+// reprents the blocks [30, 31, 32].
+static int sysMapBlockFile(const char* filename, MemMapping* pMap) {
+  CHECK(pMap != nullptr);
 
-    if (fgets(block_dev, sizeof(block_dev), mapf) == NULL) {
-        PLOG(ERROR) << "failed to read block device from header";
-        return -1;
-    }
-    for (i = 0; i < sizeof(block_dev); ++i) {
-        if (block_dev[i] == '\n') {
-            block_dev[i] = 0;
-            break;
-        }
-    }
+  std::string content;
+  if (!android::base::ReadFileToString(filename, &content)) {
+    PLOG(ERROR) << "Failed to read " << filename;
+    return -1;
+  }
 
-    if (fscanf(mapf, "%zu %u\n%u\n", &size, &blksize, &range_count) != 3) {
-        LOG(ERROR) << "failed to parse block map header";
-        return -1;
-    }
-    if (blksize != 0) {
-        blocks = ((size-1) / blksize) + 1;
-    }
-    if (size == 0 || blksize == 0 || blocks > SIZE_MAX / blksize || range_count == 0) {
-        LOG(ERROR) << "invalid data in block map file: size " << size << ", blksize " << blksize
-                   << ", range_count " << range_count;
-        return -1;
-    }
+  std::vector<std::string> lines = android::base::Split(android::base::Trim(content), "\n");
+  if (lines.size() < 4) {
+    LOG(ERROR) << "Block map file is too short: " << lines.size();
+    return -1;
+  }
 
-    pMap->range_count = range_count;
-    pMap->ranges = reinterpret_cast<MappedRange*>(calloc(range_count, sizeof(MappedRange)));
-    if (pMap->ranges == NULL) {
-        PLOG(ERROR) << "calloc(" << range_count << ", " << sizeof(MappedRange) << ") failed";
-        return -1;
-    }
+  size_t size;
+  unsigned int blksize;
+  if (sscanf(lines[1].c_str(), "%zu %u", &size, &blksize) != 2) {
+    LOG(ERROR) << "Failed to parse file size and block size: " << lines[1];
+    return -1;
+  }
 
-    // Reserve enough contiguous address space for the whole file.
-    unsigned char* reserve = reinterpret_cast<unsigned char*>(mmap64(NULL, blocks * blksize,
-            PROT_NONE, MAP_PRIVATE | MAP_ANON, -1, 0));
-    if (reserve == MAP_FAILED) {
-        PLOG(ERROR) << "failed to reserve address space";
-        free(pMap->ranges);
-        return -1;
-    }
+  size_t range_count;
+  if (sscanf(lines[2].c_str(), "%zu", &range_count) != 1) {
+    LOG(ERROR) << "Failed to parse block map header: " << lines[2];
+    return -1;
+  }
 
-    int fd = open(block_dev, O_RDONLY);
-    if (fd < 0) {
-        PLOG(ERROR) << "failed to open block device " << block_dev;
-        munmap(reserve, blocks * blksize);
-        free(pMap->ranges);
-        return -1;
-    }
+  size_t blocks;
+  if (blksize != 0) {
+    blocks = ((size - 1) / blksize) + 1;
+  }
+  if (size == 0 || blksize == 0 || blocks > SIZE_MAX / blksize || range_count == 0 ||
+      lines.size() != 3 + range_count) {
+    LOG(ERROR) << "Invalid data in block map file: size " << size << ", blksize " << blksize
+               << ", range_count " << range_count << ", lines " << lines.size();
+    return -1;
+  }
 
-    unsigned char* next = reserve;
-    size_t remaining_size = blocks * blksize;
-    bool success = true;
-    for (i = 0; i < range_count; ++i) {
-        size_t start, end;
-        if (fscanf(mapf, "%zu %zu\n", &start, &end) != 2) {
-            LOG(ERROR) << "failed to parse range " << i << " in block map";
-            success = false;
-            break;
-        }
-        size_t length = (end - start) * blksize;
-        if (end <= start || (end - start) > SIZE_MAX / blksize || length > remaining_size) {
-          LOG(ERROR) << "unexpected range in block map: " << start << " " << end;
-          success = false;
-          break;
-        }
+  // Reserve enough contiguous address space for the whole file.
+  void* reserve = mmap64(nullptr, blocks * blksize, PROT_NONE, MAP_PRIVATE | MAP_ANON, -1, 0);
+  if (reserve == MAP_FAILED) {
+    PLOG(ERROR) << "failed to reserve address space";
+    return -1;
+  }
 
-        void* addr = mmap64(next, length, PROT_READ, MAP_PRIVATE | MAP_FIXED, fd, ((off64_t)start)*blksize);
-        if (addr == MAP_FAILED) {
-            PLOG(ERROR) << "failed to map block " << i;
-            success = false;
-            break;
-        }
-        pMap->ranges[i].addr = addr;
-        pMap->ranges[i].length = length;
+  const std::string& block_dev = lines[0];
+  android::base::unique_fd fd(TEMP_FAILURE_RETRY(open(block_dev.c_str(), O_RDONLY)));
+  if (fd == -1) {
+    PLOG(ERROR) << "failed to open block device " << block_dev;
+    munmap(reserve, blocks * blksize);
+    return -1;
+  }
 
-        next += length;
-        remaining_size -= length;
-    }
-    if (success && remaining_size != 0) {
-      LOG(ERROR) << "ranges in block map are invalid: remaining_size = " << remaining_size;
+  pMap->ranges.resize(range_count);
+
+  unsigned char* next = static_cast<unsigned char*>(reserve);
+  size_t remaining_size = blocks * blksize;
+  bool success = true;
+  for (size_t i = 0; i < range_count; ++i) {
+    const std::string& line = lines[i + 3];
+
+    size_t start, end;
+    if (sscanf(line.c_str(), "%zu %zu\n", &start, &end) != 2) {
+      LOG(ERROR) << "failed to parse range " << i << " in block map: " << line;
       success = false;
+      break;
     }
-    if (!success) {
-      close(fd);
-      munmap(reserve, blocks * blksize);
-      free(pMap->ranges);
+    size_t length = (end - start) * blksize;
+    if (end <= start || (end - start) > SIZE_MAX / blksize || length > remaining_size) {
+      LOG(ERROR) << "unexpected range in block map: " << start << " " << end;
+      success = false;
+      break;
+    }
+
+    void* addr = mmap64(next, length, PROT_READ, MAP_PRIVATE | MAP_FIXED, fd,
+                        static_cast<off64_t>(start) * blksize);
+    if (addr == MAP_FAILED) {
+      PLOG(ERROR) << "failed to map block " << i;
+      success = false;
+      break;
+    }
+    pMap->ranges[i].addr = addr;
+    pMap->ranges[i].length = length;
+
+    next += length;
+    remaining_size -= length;
+  }
+  if (success && remaining_size != 0) {
+    LOG(ERROR) << "ranges in block map are invalid: remaining_size = " << remaining_size;
+    success = false;
+  }
+  if (!success) {
+    munmap(reserve, blocks * blksize);
+    return -1;
+  }
+
+  pMap->addr = static_cast<unsigned char*>(reserve);
+  pMap->length = size;
+
+  LOG(INFO) << "mmapped " << range_count << " ranges";
+
+  return 0;
+}
+
+int sysMapFile(const char* fn, MemMapping* pMap) {
+  if (fn == nullptr || pMap == nullptr) {
+    LOG(ERROR) << "Invalid argument(s)";
+    return -1;
+  }
+
+  *pMap = {};
+
+  if (fn[0] == '@') {
+    if (sysMapBlockFile(fn + 1, pMap) != 0) {
+      LOG(ERROR) << "Map of '" << fn << "' failed";
+      return -1;
+    }
+  } else {
+    // This is a regular file.
+    android::base::unique_fd fd(TEMP_FAILURE_RETRY(open(fn, O_RDONLY)));
+    if (fd == -1) {
+      PLOG(ERROR) << "Unable to open '" << fn << "'";
       return -1;
     }
 
-    close(fd);
-    pMap->addr = reserve;
-    pMap->length = size;
-
-    LOG(INFO) << "mmapped " << range_count << " ranges";
-
-    return 0;
-}
-
-int sysMapFile(const char* fn, MemMapping* pMap)
-{
-    memset(pMap, 0, sizeof(*pMap));
-
-    if (fn && fn[0] == '@') {
-        // A map of blocks
-        FILE* mapf = fopen(fn+1, "r");
-        if (mapf == NULL) {
-            PLOG(ERROR) << "Unable to open '" << (fn+1) << "'";
-            return -1;
-        }
-
-        if (sysMapBlockFile(mapf, pMap) != 0) {
-            LOG(ERROR) << "Map of '" << fn << "' failed";
-            fclose(mapf);
-            return -1;
-        }
-
-        fclose(mapf);
-    } else {
-        // This is a regular file.
-        int fd = open(fn, O_RDONLY);
-        if (fd == -1) {
-            PLOG(ERROR) << "Unable to open '" << fn << "'";
-            return -1;
-        }
-
-        if (!sysMapFD(fd, pMap)) {
-            LOG(ERROR) << "Map of '" << fn << "' failed";
-            close(fd);
-            return -1;
-        }
-
-        close(fd);
+    if (!sysMapFD(fd, pMap)) {
+      LOG(ERROR) << "Map of '" << fn << "' failed";
+      return -1;
     }
-    return 0;
+  }
+  return 0;
 }
 
 /*
  * Release a memory mapping.
  */
-void sysReleaseMap(MemMapping* pMap)
-{
-    int i;
-    for (i = 0; i < pMap->range_count; ++i) {
-        if (munmap(pMap->ranges[i].addr, pMap->ranges[i].length) < 0) {
-            PLOG(ERROR) << "munmap(" << pMap->ranges[i].addr << ", " << pMap->ranges[i].length
-                        << ") failed";
-        }
+void sysReleaseMap(MemMapping* pMap) {
+  std::for_each(pMap->ranges.cbegin(), pMap->ranges.cend(), [](const MappedRange& range) {
+    if (munmap(range.addr, range.length) == -1) {
+      PLOG(ERROR) << "munmap(" << range.addr << ", " << range.length << ") failed";
     }
-    free(pMap->ranges);
-    pMap->ranges = NULL;
-    pMap->range_count = 0;
+  });
+  pMap->ranges.clear();
 }
diff --git a/otautil/SysUtil.h b/otautil/SysUtil.h
index 7adff1e..6a79bf3 100644
--- a/otautil/SysUtil.h
+++ b/otautil/SysUtil.h
@@ -1,33 +1,40 @@
 /*
  * Copyright 2006 The Android Open Source Project
  *
- * System utilities.
+ * 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 _MINZIP_SYSUTIL
-#define _MINZIP_SYSUTIL
 
-#include <stdio.h>
+#ifndef _OTAUTIL_SYSUTIL
+#define _OTAUTIL_SYSUTIL
+
 #include <sys/types.h>
 
-#ifdef __cplusplus
-extern "C" {
-#endif
+#include <vector>
 
-typedef struct MappedRange {
-    void* addr;
-    size_t length;
-} MappedRange;
+struct MappedRange {
+  void* addr;
+  size_t length;
+};
 
 /*
  * Use this to keep track of mapped segments.
  */
-typedef struct MemMapping {
-    unsigned char* addr;           /* start of data */
-    size_t         length;         /* length of data */
+struct MemMapping {
+  unsigned char* addr; /* start of data */
+  size_t length;       /* length of data */
 
-    int            range_count;
-    MappedRange*   ranges;
-} MemMapping;
+  std::vector<MappedRange> ranges;
+};
 
 /*
  * Map a file into a private, read-only memory segment.  If 'fn'
@@ -45,8 +52,4 @@
  */
 void sysReleaseMap(MemMapping* pMap);
 
-#ifdef __cplusplus
-}
-#endif
-
-#endif /*_MINZIP_SYSUTIL*/
+#endif  // _OTAUTIL_SYSUTIL
diff --git a/tests/Android.mk b/tests/Android.mk
index 8f19992..e87a229 100644
--- a/tests/Android.mk
+++ b/tests/Android.mk
@@ -18,7 +18,6 @@
 
 # Unit tests
 include $(CLEAR_VARS)
-LOCAL_CLANG := true
 LOCAL_CFLAGS := -Werror
 LOCAL_MODULE := recovery_unit_test
 LOCAL_ADDITIONAL_DEPENDENCIES := $(LOCAL_PATH)/Android.mk
@@ -32,17 +31,30 @@
     libselinux \
     libbase
 
-LOCAL_SRC_FILES := unit/asn1_decoder_test.cpp
-LOCAL_SRC_FILES += unit/recovery_test.cpp
-LOCAL_SRC_FILES += unit/locale_test.cpp
-LOCAL_SRC_FILES += unit/zip_test.cpp
+LOCAL_SRC_FILES := \
+    unit/asn1_decoder_test.cpp \
+    unit/locale_test.cpp \
+    unit/sysutil_test.cpp \
+    unit/zip_test.cpp
+
 LOCAL_C_INCLUDES := bootable/recovery
 LOCAL_SHARED_LIBRARIES := liblog
 include $(BUILD_NATIVE_TEST)
 
+# Manual tests
+include $(CLEAR_VARS)
+LOCAL_CLANG := true
+LOCAL_CFLAGS := -Werror
+LOCAL_MODULE := recovery_manual_test
+LOCAL_ADDITIONAL_DEPENDENCIES := $(LOCAL_PATH)/Android.mk
+LOCAL_STATIC_LIBRARIES := libbase
+
+LOCAL_SRC_FILES := manual/recovery_test.cpp
+LOCAL_SHARED_LIBRARIES := liblog
+include $(BUILD_NATIVE_TEST)
+
 # Component tests
 include $(CLEAR_VARS)
-LOCAL_CLANG := true
 LOCAL_CFLAGS := -Werror
 LOCAL_ADDITIONAL_DEPENDENCIES := $(LOCAL_PATH)/Android.mk
 LOCAL_MODULE := recovery_component_test
diff --git a/tests/component/updater_test.cpp b/tests/component/updater_test.cpp
index f922933..973c19d 100644
--- a/tests/component/updater_test.cpp
+++ b/tests/component/updater_test.cpp
@@ -14,6 +14,10 @@
  * limitations under the License.
  */
 
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <unistd.h>
+
 #include <string>
 
 #include <android-base/file.h>
@@ -208,4 +212,55 @@
 
     // Already renamed.
     expect(temp_file2.path, script2.c_str(), kNoCause);
+
+    // Parents create successfully.
+    TemporaryFile temp_file3;
+    TemporaryDir td;
+    std::string temp_dir(td.path);
+    std::string dst_file = temp_dir + "/aaa/bbb/a.txt";
+    std::string script3("rename(\"" + std::string(temp_file3.path) + "\", \"" + dst_file + "\")");
+    expect(dst_file.c_str(), script3.c_str(), kNoCause);
+
+    // Clean up the temp files under td.
+    ASSERT_EQ(0, unlink(dst_file.c_str()));
+    ASSERT_EQ(0, rmdir((temp_dir + "/aaa/bbb").c_str()));
+    ASSERT_EQ(0, rmdir((temp_dir + "/aaa").c_str()));
+}
+
+TEST_F(UpdaterTest, symlink) {
+    // symlink expects 1+ argument.
+    expect(nullptr, "symlink()", kArgsParsingFailure);
+
+    // symlink should fail if src is an empty string.
+    TemporaryFile temp_file1;
+    std::string script1("symlink(\"" + std::string(temp_file1.path) + "\", \"\")");
+    expect(nullptr, script1.c_str(), kSymlinkFailure);
+
+    std::string script2("symlink(\"" + std::string(temp_file1.path) + "\", \"src1\", \"\")");
+    expect(nullptr, script2.c_str(), kSymlinkFailure);
+
+    // symlink failed to remove old src.
+    std::string script3("symlink(\"" + std::string(temp_file1.path) + "\", \"/proc\")");
+    expect(nullptr, script3.c_str(), kSymlinkFailure);
+
+    // symlink can create symlinks.
+    TemporaryFile temp_file;
+    std::string content = "magicvalue";
+    ASSERT_TRUE(android::base::WriteStringToFile(content, temp_file.path));
+
+    TemporaryDir td;
+    std::string src1 = std::string(td.path) + "/symlink1";
+    std::string src2 = std::string(td.path) + "/symlink2";
+    std::string script4("symlink(\"" + std::string(temp_file.path) + "\", \"" +
+                        src1 + "\", \"" + src2 + "\")");
+    expect("t", script4.c_str(), kNoCause);
+
+    // Verify the created symlinks.
+    struct stat sb;
+    ASSERT_TRUE(lstat(src1.c_str(), &sb) == 0 && S_ISLNK(sb.st_mode));
+    ASSERT_TRUE(lstat(src2.c_str(), &sb) == 0 && S_ISLNK(sb.st_mode));
+
+    // Clean up the leftovers.
+    ASSERT_EQ(0, unlink(src1.c_str()));
+    ASSERT_EQ(0, unlink(src2.c_str()));
 }
diff --git a/tests/manual/recovery_test.cpp b/tests/manual/recovery_test.cpp
new file mode 100644
index 0000000..e838495
--- /dev/null
+++ b/tests/manual/recovery_test.cpp
@@ -0,0 +1,87 @@
+/*
+ * Copyright (C) 2016 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.
+ */
+
+#include <fcntl.h>
+#include <string.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#include <string>
+
+#include <android-base/file.h>
+#include <android/log.h>
+#include <gtest/gtest.h>
+#include <private/android_logger.h>
+
+static const std::string myFilename = "/data/misc/recovery/inject.txt";
+static const std::string myContent = "Hello World\nWelcome to my recovery\n";
+
+// Failure is expected on systems that do not deliver either the
+// recovery-persist or recovery-refresh executables. Tests also require
+// a reboot sequence of test to truly verify.
+
+static ssize_t __pmsg_fn(log_id_t logId, char prio, const char *filename,
+                         const char *buf, size_t len, void *arg) {
+  EXPECT_EQ(LOG_ID_SYSTEM, logId);
+  EXPECT_EQ(ANDROID_LOG_INFO, prio);
+  EXPECT_NE(std::string::npos, myFilename.find(filename));
+  EXPECT_EQ(myContent, buf);
+  EXPECT_EQ(myContent.size(), len);
+  EXPECT_EQ(nullptr, arg);
+  return len;
+}
+
+// recovery.refresh - May fail. Requires recovery.inject, two reboots,
+//                    then expect success after second reboot.
+TEST(recovery, refresh) {
+  EXPECT_EQ(0, access("/system/bin/recovery-refresh", F_OK));
+
+  ssize_t ret = __android_log_pmsg_file_read(
+      LOG_ID_SYSTEM, ANDROID_LOG_INFO, "recovery/", __pmsg_fn, nullptr);
+  if (ret == -ENOENT) {
+    EXPECT_LT(0, __android_log_pmsg_file_write(LOG_ID_SYSTEM, ANDROID_LOG_INFO,
+        myFilename.c_str(), myContent.c_str(), myContent.size()));
+
+    fprintf(stderr, "injected test data, requires two intervening reboots "
+        "to check for replication\n");
+  }
+  EXPECT_EQ(static_cast<ssize_t>(myContent.size()), ret);
+}
+
+// recovery.persist - Requires recovery.inject, then a reboot, then
+//                    expect success after for this test on that boot.
+TEST(recovery, persist) {
+  EXPECT_EQ(0, access("/system/bin/recovery-persist", F_OK));
+
+  ssize_t ret = __android_log_pmsg_file_read(
+      LOG_ID_SYSTEM, ANDROID_LOG_INFO, "recovery/", __pmsg_fn, nullptr);
+  if (ret == -ENOENT) {
+    EXPECT_LT(0, __android_log_pmsg_file_write(LOG_ID_SYSTEM, ANDROID_LOG_INFO,
+        myFilename.c_str(), myContent.c_str(), myContent.size()));
+
+    fprintf(stderr, "injected test data, requires intervening reboot "
+        "to check for storage\n");
+  }
+
+  std::string buf;
+  EXPECT_TRUE(android::base::ReadFileToString(myFilename, &buf));
+  EXPECT_EQ(myContent, buf);
+  if (access(myFilename.c_str(), O_RDONLY) == 0) {
+    fprintf(stderr, "Removing persistent test data, "
+        "check if reconstructed on reboot\n");
+  }
+  EXPECT_EQ(0, unlink(myFilename.c_str()));
+}
diff --git a/tests/unit/recovery_test.cpp b/tests/unit/recovery_test.cpp
deleted file mode 100644
index 28b845f..0000000
--- a/tests/unit/recovery_test.cpp
+++ /dev/null
@@ -1,91 +0,0 @@
-/*
- * Copyright (C) 2016 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.
- */
-
-#include <fcntl.h>
-#include <string.h>
-#include <sys/types.h>
-#include <unistd.h>
-
-#include <android/log.h>
-#include <gtest/gtest.h>
-#include <private/android_logger.h>
-
-static const char myFilename[] = "/data/misc/recovery/inject.txt";
-static const char myContent[] = "Hello World\nWelcome to my recovery\n";
-
-// Failure is expected on systems that do not deliver either the
-// recovery-persist or recovery-refresh executables. Tests also require
-// a reboot sequence of test to truly verify.
-
-static ssize_t __pmsg_fn(log_id_t logId, char prio, const char *filename,
-                         const char *buf, size_t len, void *arg) {
-    EXPECT_EQ(LOG_ID_SYSTEM, logId);
-    EXPECT_EQ(ANDROID_LOG_INFO, prio);
-    EXPECT_EQ(0, NULL == strstr(myFilename,filename));
-    EXPECT_EQ(0, strcmp(myContent, buf));
-    EXPECT_EQ(sizeof(myContent), len);
-    EXPECT_EQ(0, NULL != arg);
-    return len;
-}
-
-// recovery.refresh - May fail. Requires recovery.inject, two reboots,
-//                    then expect success after second reboot.
-TEST(recovery, refresh) {
-    EXPECT_EQ(0, access("/system/bin/recovery-refresh", F_OK));
-
-    ssize_t ret = __android_log_pmsg_file_read(
-        LOG_ID_SYSTEM, ANDROID_LOG_INFO, "recovery/", __pmsg_fn, NULL);
-    if (ret == -ENOENT) {
-        EXPECT_LT(0, __android_log_pmsg_file_write(
-            LOG_ID_SYSTEM, ANDROID_LOG_INFO,
-            myFilename, myContent, sizeof(myContent)));
-        fprintf(stderr, "injected test data, "
-                        "requires two intervening reboots "
-                        "to check for replication\n");
-    }
-    EXPECT_EQ((ssize_t)sizeof(myContent), ret);
-}
-
-// recovery.persist - Requires recovery.inject, then a reboot, then
-//                    expect success after for this test on that boot.
-TEST(recovery, persist) {
-    EXPECT_EQ(0, access("/system/bin/recovery-persist", F_OK));
-
-    ssize_t ret = __android_log_pmsg_file_read(
-        LOG_ID_SYSTEM, ANDROID_LOG_INFO, "recovery/", __pmsg_fn, NULL);
-    if (ret == -ENOENT) {
-        EXPECT_LT(0, __android_log_pmsg_file_write(
-            LOG_ID_SYSTEM, ANDROID_LOG_INFO,
-            myFilename, myContent, sizeof(myContent)));
-        fprintf(stderr, "injected test data, "
-                        "requires intervening reboot "
-                        "to check for storage\n");
-    }
-
-    int fd = open(myFilename, O_RDONLY);
-    EXPECT_LE(0, fd);
-
-    char buf[sizeof(myContent) + 32];
-    ret = read(fd, buf, sizeof(buf));
-    close(fd);
-    EXPECT_EQ(ret, (ssize_t)sizeof(myContent));
-    EXPECT_EQ(0, strcmp(myContent, buf));
-    if (fd >= 0) {
-        fprintf(stderr, "Removing persistent test data, "
-                        "check if reconstructed on reboot\n");
-    }
-    EXPECT_EQ(0, unlink(myFilename));
-}
diff --git a/tests/unit/sysutil_test.cpp b/tests/unit/sysutil_test.cpp
new file mode 100644
index 0000000..f469966
--- /dev/null
+++ b/tests/unit/sysutil_test.cpp
@@ -0,0 +1,140 @@
+/*
+ * Copyright 2016 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.
+ */
+
+#include <gtest/gtest.h>
+
+#include <string>
+
+#include <android-base/file.h>
+#include <android-base/test_utils.h>
+
+#include "otautil/SysUtil.h"
+
+TEST(SysUtilTest, InvalidArgs) {
+  MemMapping mapping;
+
+  // Invalid argument.
+  ASSERT_EQ(-1, sysMapFile(nullptr, &mapping));
+  ASSERT_EQ(-1, sysMapFile("/somefile", nullptr));
+}
+
+TEST(SysUtilTest, sysMapFileRegularFile) {
+  TemporaryFile temp_file1;
+  std::string content = "abc";
+  ASSERT_TRUE(android::base::WriteStringToFile(content, temp_file1.path));
+
+  // sysMapFile() should map the file to one range.
+  MemMapping mapping;
+  ASSERT_EQ(0, sysMapFile(temp_file1.path, &mapping));
+  ASSERT_NE(nullptr, mapping.addr);
+  ASSERT_EQ(content.size(), mapping.length);
+  ASSERT_EQ(1U, mapping.ranges.size());
+
+  sysReleaseMap(&mapping);
+  ASSERT_EQ(0U, mapping.ranges.size());
+}
+
+TEST(SysUtilTest, sysMapFileBlockMap) {
+  // Create a file that has 10 blocks.
+  TemporaryFile package;
+  std::string content;
+  constexpr size_t file_size = 4096 * 10;
+  content.reserve(file_size);
+  ASSERT_TRUE(android::base::WriteStringToFile(content, package.path));
+
+  TemporaryFile block_map_file;
+  std::string filename = std::string("@") + block_map_file.path;
+  MemMapping mapping;
+
+  // One range.
+  std::string block_map_content = std::string(package.path) + "\n40960 4096\n1\n0 10\n";
+  ASSERT_TRUE(android::base::WriteStringToFile(block_map_content, block_map_file.path));
+
+  ASSERT_EQ(0, sysMapFile(filename.c_str(), &mapping));
+  ASSERT_EQ(file_size, mapping.length);
+  ASSERT_EQ(1U, mapping.ranges.size());
+
+  // It's okay to not have the trailing '\n'.
+  block_map_content = std::string(package.path) + "\n40960 4096\n1\n0 10";
+  ASSERT_TRUE(android::base::WriteStringToFile(block_map_content, block_map_file.path));
+
+  ASSERT_EQ(0, sysMapFile(filename.c_str(), &mapping));
+  ASSERT_EQ(file_size, mapping.length);
+  ASSERT_EQ(1U, mapping.ranges.size());
+
+  // Or having multiple trailing '\n's.
+  block_map_content = std::string(package.path) + "\n40960 4096\n1\n0 10\n\n\n";
+  ASSERT_TRUE(android::base::WriteStringToFile(block_map_content, block_map_file.path));
+
+  ASSERT_EQ(0, sysMapFile(filename.c_str(), &mapping));
+  ASSERT_EQ(file_size, mapping.length);
+  ASSERT_EQ(1U, mapping.ranges.size());
+
+  // Multiple ranges.
+  block_map_content = std::string(package.path) + "\n40960 4096\n3\n0 3\n3 5\n5 10\n";
+  ASSERT_TRUE(android::base::WriteStringToFile(block_map_content, block_map_file.path));
+
+  ASSERT_EQ(0, sysMapFile(filename.c_str(), &mapping));
+  ASSERT_EQ(file_size, mapping.length);
+  ASSERT_EQ(3U, mapping.ranges.size());
+
+  sysReleaseMap(&mapping);
+  ASSERT_EQ(0U, mapping.ranges.size());
+}
+
+TEST(SysUtilTest, sysMapFileBlockMapInvalidBlockMap) {
+  MemMapping mapping;
+  TemporaryFile temp_file;
+  std::string filename = std::string("@") + temp_file.path;
+
+  // Block map file is too short.
+  ASSERT_TRUE(android::base::WriteStringToFile("/somefile\n", temp_file.path));
+  ASSERT_EQ(-1, sysMapFile(filename.c_str(), &mapping));
+
+  ASSERT_TRUE(android::base::WriteStringToFile("/somefile\n4096 4096\n0\n", temp_file.path));
+  ASSERT_EQ(-1, sysMapFile(filename.c_str(), &mapping));
+
+  // Block map file has unexpected number of lines.
+  ASSERT_TRUE(android::base::WriteStringToFile("/somefile\n4096 4096\n1\n", temp_file.path));
+  ASSERT_EQ(-1, sysMapFile(filename.c_str(), &mapping));
+
+  ASSERT_TRUE(android::base::WriteStringToFile("/somefile\n4096 4096\n2\n0 1\n", temp_file.path));
+  ASSERT_EQ(-1, sysMapFile(filename.c_str(), &mapping));
+
+  // Invalid size/blksize/range_count.
+  ASSERT_TRUE(android::base::WriteStringToFile("/somefile\nabc 4096\n1\n0 1\n", temp_file.path));
+  ASSERT_EQ(-1, sysMapFile(filename.c_str(), &mapping));
+
+  ASSERT_TRUE(android::base::WriteStringToFile("/somefile\n4096 4096\n\n0 1\n", temp_file.path));
+  ASSERT_EQ(-1, sysMapFile(filename.c_str(), &mapping));
+
+  // size/blksize/range_count don't match.
+  ASSERT_TRUE(android::base::WriteStringToFile("/somefile\n0 4096\n1\n0 1\n", temp_file.path));
+  ASSERT_EQ(-1, sysMapFile(filename.c_str(), &mapping));
+
+  ASSERT_TRUE(android::base::WriteStringToFile("/somefile\n4096 0\n1\n0 1\n", temp_file.path));
+  ASSERT_EQ(-1, sysMapFile(filename.c_str(), &mapping));
+
+  ASSERT_TRUE(android::base::WriteStringToFile("/somefile\n4096 4096\n0\n0 1\n", temp_file.path));
+  ASSERT_EQ(-1, sysMapFile(filename.c_str(), &mapping));
+
+  // Invalid block dev path.
+  ASSERT_TRUE(android::base::WriteStringToFile("/doesntexist\n4096 4096\n1\n0 1\n", temp_file.path));
+  ASSERT_EQ(-1, sysMapFile(filename.c_str(), &mapping));
+
+  sysReleaseMap(&mapping);
+  ASSERT_EQ(0U, mapping.ranges.size());
+}
diff --git a/tests/unit/zip_test.cpp b/tests/unit/zip_test.cpp
index b617446..4972946 100644
--- a/tests/unit/zip_test.cpp
+++ b/tests/unit/zip_test.cpp
@@ -16,78 +16,69 @@
 
 #include <errno.h>
 #include <fcntl.h>
-#include <pthread.h>
 #include <unistd.h>
 
 #include <memory>
 #include <vector>
 
 #include <android-base/file.h>
-#include <android-base/stringprintf.h>
-#include <android-base/unique_fd.h>
 #include <android-base/test_utils.h>
 #include <gtest/gtest.h>
 #include <otautil/SysUtil.h>
 #include <otautil/ZipUtil.h>
 #include <ziparchive/zip_archive.h>
 
-static const std::string DATA_PATH(getenv("ANDROID_DATA"));
-static const std::string TESTDATA_PATH("/recovery/testdata/");
+#include "common/test_constants.h"
 
-static const std::vector<uint8_t> kATxtContents {
-    'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h',
-    'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h',
-    '\n'
-};
+static const std::string kATxtContents("abcdefghabcdefgh\n");
+static const std::string kBTxtContents("abcdefgh\n");
 
-static const std::vector<uint8_t> kBTxtContents {
-    'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h',
-    '\n'
-};
+TEST(ZipTest, ExtractPackageRecursive) {
+  std::string zip_path = from_testdata_base("ziptest_valid.zip");
+  ZipArchiveHandle handle;
+  ASSERT_EQ(0, OpenArchive(zip_path.c_str(), &handle));
 
-TEST(otazip, ExtractPackageRecursive) {
-    TemporaryDir td;
-    ASSERT_NE(td.path, nullptr);
-    ZipArchiveHandle handle;
-    std::string zip_path = DATA_PATH + TESTDATA_PATH + "/ziptest_valid.zip";
-    ASSERT_EQ(0, OpenArchive(zip_path.c_str(), &handle));
-    // Extract the whole package into a temp directory.
-    ExtractPackageRecursive(handle, "", td.path, nullptr, nullptr);
-    // Make sure all the files are extracted correctly.
-    std::string path(td.path);
-    android::base::unique_fd fd(open((path + "/a.txt").c_str(), O_RDONLY));
-    ASSERT_NE(fd, -1);
-    std::vector<uint8_t> read_data;
-    read_data.resize(kATxtContents.size());
-    // The content of the file is the same as expected.
-    ASSERT_TRUE(android::base::ReadFully(fd.get(), read_data.data(), read_data.size()));
-    ASSERT_EQ(0, memcmp(read_data.data(), kATxtContents.data(), kATxtContents.size()));
+  // Extract the whole package into a temp directory.
+  TemporaryDir td;
+  ASSERT_NE(nullptr, td.path);
+  ExtractPackageRecursive(handle, "", td.path, nullptr, nullptr);
 
-    fd.reset(open((path + "/b.txt").c_str(), O_RDONLY));
-    ASSERT_NE(fd, -1);
-    fd.reset(open((path + "/b/c.txt").c_str(), O_RDONLY));
-    ASSERT_NE(fd, -1);
-    fd.reset(open((path + "/b/d.txt").c_str(), O_RDONLY));
-    ASSERT_NE(fd, -1);
-    read_data.resize(kBTxtContents.size());
-    ASSERT_TRUE(android::base::ReadFully(fd.get(), read_data.data(), read_data.size()));
-    ASSERT_EQ(0, memcmp(read_data.data(), kBTxtContents.data(), kBTxtContents.size()));
+  // Make sure all the files are extracted correctly.
+  std::string path(td.path);
+  ASSERT_EQ(0, access((path + "/a.txt").c_str(), O_RDONLY));
+  ASSERT_EQ(0, access((path + "/b.txt").c_str(), O_RDONLY));
+  ASSERT_EQ(0, access((path + "/b/c.txt").c_str(), O_RDONLY));
+  ASSERT_EQ(0, access((path + "/b/d.txt").c_str(), O_RDONLY));
+
+  // The content of the file is the same as expected.
+  std::string content1;
+  ASSERT_TRUE(android::base::ReadFileToString(path + "/a.txt", &content1));
+  ASSERT_EQ(kATxtContents, content1);
+
+  std::string content2;
+  ASSERT_TRUE(android::base::ReadFileToString(path + "/b/d.txt", &content2));
+  ASSERT_EQ(kBTxtContents, content2);
 }
 
-TEST(otazip, OpenFromMemory) {
-    MemMapping map;
-    std::string zip_path = DATA_PATH + TESTDATA_PATH + "/ziptest_dummy-update.zip";
-    ASSERT_EQ(0, sysMapFile(zip_path.c_str(), &map));
-    // Map an update package into memory and open the archive from there.
-    ZipArchiveHandle handle;
-    ASSERT_EQ(0, OpenArchiveFromMemory(map.addr, map.length, zip_path.c_str(), &handle));
-    static constexpr const char* BINARY_PATH = "META-INF/com/google/android/update-binary";
-    ZipString binary_path(BINARY_PATH);
-    ZipEntry binary_entry;
-    // Make sure the package opens correctly and its entry can be read.
-    ASSERT_EQ(0, FindEntry(handle, binary_path, &binary_entry));
-    TemporaryFile tmp_binary;
-    ASSERT_NE(-1, tmp_binary.fd);
-    ASSERT_EQ(0, ExtractEntryToFile(handle, &binary_entry, tmp_binary.fd));
+TEST(ZipTest, OpenFromMemory) {
+  MemMapping map;
+  std::string zip_path = from_testdata_base("ziptest_dummy-update.zip");
+  ASSERT_EQ(0, sysMapFile(zip_path.c_str(), &map));
+
+  // Map an update package into memory and open the archive from there.
+  ZipArchiveHandle handle;
+  ASSERT_EQ(0, OpenArchiveFromMemory(map.addr, map.length, zip_path.c_str(), &handle));
+
+  static constexpr const char* BINARY_PATH = "META-INF/com/google/android/update-binary";
+  ZipString binary_path(BINARY_PATH);
+  ZipEntry binary_entry;
+  // Make sure the package opens correctly and its entry can be read.
+  ASSERT_EQ(0, FindEntry(handle, binary_path, &binary_entry));
+
+  TemporaryFile tmp_binary;
+  ASSERT_NE(-1, tmp_binary.fd);
+  ASSERT_EQ(0, ExtractEntryToFile(handle, &binary_entry, tmp_binary.fd));
+
+  sysReleaseMap(&map);
 }
 
diff --git a/uncrypt/uncrypt.cpp b/uncrypt/uncrypt.cpp
index a5d692b..e1b6a1c 100644
--- a/uncrypt/uncrypt.cpp
+++ b/uncrypt/uncrypt.cpp
@@ -210,6 +210,11 @@
 }
 
 static bool write_status_to_socket(int status, int socket) {
+    // If socket equals -1, uncrypt is in debug mode without socket communication.
+    // Skip writing and return success.
+    if (socket == -1) {
+        return true;
+    }
     int status_out = htonl(status);
     return android::base::WriteFully(socket, &status_out, sizeof(int));
 }
@@ -566,7 +571,7 @@
 }
 
 int main(int argc, char** argv) {
-    enum { UNCRYPT, SETUP_BCB, CLEAR_BCB } action;
+    enum { UNCRYPT, SETUP_BCB, CLEAR_BCB, UNCRYPT_DEBUG } action;
     const char* input_path = nullptr;
     const char* map_file = CACHE_BLOCK_MAP.c_str();
 
@@ -579,7 +584,7 @@
     } else if (argc == 3) {
         input_path = argv[1];
         map_file = argv[2];
-        action = UNCRYPT;
+        action = UNCRYPT_DEBUG;
     } else {
         usage(argv[0]);
         return 2;
@@ -593,6 +598,17 @@
         return 1;
     }
 
+    if (action == UNCRYPT_DEBUG) {
+        LOG(INFO) << "uncrypt called in debug mode, skip socket communication\n";
+        bool success = uncrypt_wrapper(input_path, map_file, -1);
+        if (success) {
+            LOG(INFO) << "uncrypt succeeded\n";
+        } else{
+            LOG(INFO) << "uncrypt failed\n";
+        }
+        return success ? 0 : 1;
+    }
+
     // c3. The socket is created by init when starting the service. uncrypt
     // will use the socket to communicate with its caller.
     android::base::unique_fd service_socket(android_get_control_socket(UNCRYPT_SOCKET.c_str()));
diff --git a/update_verifier/Android.mk b/update_verifier/Android.mk
index 8f5194d..8449c75 100644
--- a/update_verifier/Android.mk
+++ b/update_verifier/Android.mk
@@ -18,8 +18,15 @@
 
 LOCAL_CLANG := true
 LOCAL_SRC_FILES := update_verifier.cpp
+
 LOCAL_MODULE := update_verifier
-LOCAL_SHARED_LIBRARIES := libhardware libbase
+LOCAL_SHARED_LIBRARIES := \
+    libbase \
+    libcutils \
+    libhardware \
+    liblog
+
 LOCAL_CFLAGS := -Werror
+LOCAL_C_INCLUDES += $(LOCAL_PATH)/..
 
 include $(BUILD_EXECUTABLE)
diff --git a/update_verifier/update_verifier.cpp b/update_verifier/update_verifier.cpp
index 0a040c5..93ac605 100644
--- a/update_verifier/update_verifier.cpp
+++ b/update_verifier/update_verifier.cpp
@@ -22,22 +22,121 @@
  * It relies on dm-verity to capture any corruption on the partitions being
  * verified. dm-verity must be in enforcing mode, so that it will reboot the
  * device on dm-verity failures. When that happens, the bootloader should
- * mark the slot as unbootable and stops trying. We should never see a device
- * started in dm-verity logging mode but with isSlotMarkedSuccessful equals to
- * 0.
+ * mark the slot as unbootable and stops trying. Other dm-verity modes (
+ * for example, veritymode=EIO) are not accepted and simply lead to a
+ * verification failure.
  *
  * The current slot will be marked as having booted successfully if the
  * verifier reaches the end after the verification.
  *
- * TODO: The actual verification part will be added later after we have the
- * A/B OTA package format in place.
  */
 
+#include <errno.h>
+#include <fcntl.h>
+#include <stdio.h>
 #include <string.h>
 
+#include <string>
+#include <vector>
+
+#include <android-base/file.h>
 #include <android-base/logging.h>
+#include <android-base/parseint.h>
+#include <android-base/strings.h>
+#include <android-base/unique_fd.h>
+#include <cutils/properties.h>
 #include <hardware/boot_control.h>
 
+constexpr auto CARE_MAP_FILE = "/data/ota_package/care_map.txt";
+constexpr int BLOCKSIZE = 4096;
+
+static bool read_blocks(const std::string& blk_device_prefix, const std::string& range_str) {
+    char slot_suffix[PROPERTY_VALUE_MAX];
+    property_get("ro.boot.slot_suffix", slot_suffix, "");
+    std::string blk_device = blk_device_prefix + std::string(slot_suffix);
+    android::base::unique_fd fd(TEMP_FAILURE_RETRY(open(blk_device.c_str(), O_RDONLY)));
+    if (fd.get() == -1) {
+        PLOG(ERROR) << "Error reading partition " << blk_device;
+        return false;
+    }
+
+    // For block range string, first integer 'count' equals 2 * total number of valid ranges,
+    // followed by 'count' number comma separated integers. Every two integers reprensent a
+    // block range with the first number included in range but second number not included.
+    // For example '4,64536,65343,74149,74150' represents: [64536,65343) and [74149,74150).
+    std::vector<std::string> ranges = android::base::Split(range_str, ",");
+    size_t range_count;
+    bool status = android::base::ParseUint(ranges[0].c_str(), &range_count);
+    if (!status || (range_count == 0) || (range_count % 2 != 0) ||
+            (range_count != ranges.size()-1)) {
+        LOG(ERROR) << "Error in parsing range string.";
+        return false;
+    }
+
+    size_t blk_count = 0;
+    for (size_t i = 1; i < ranges.size(); i += 2) {
+        unsigned int range_start, range_end;
+        bool parse_status = android::base::ParseUint(ranges[i].c_str(), &range_start);
+        parse_status = parse_status && android::base::ParseUint(ranges[i+1].c_str(), &range_end);
+        if (!parse_status || range_start >= range_end) {
+            LOG(ERROR) << "Invalid range pair " << ranges[i] << ", " << ranges[i+1];
+            return false;
+        }
+
+        if (lseek64(fd.get(), static_cast<off64_t>(range_start) * BLOCKSIZE, SEEK_SET) == -1) {
+            PLOG(ERROR) << "lseek to " << range_start << " failed";
+            return false;
+        }
+
+        size_t size = (range_end - range_start) * BLOCKSIZE;
+        std::vector<uint8_t> buf(size);
+        if (!android::base::ReadFully(fd.get(), buf.data(), size)) {
+            PLOG(ERROR) << "Failed to read blocks " << range_start << " to " << range_end;
+            return false;
+        }
+        blk_count += (range_end - range_start);
+    }
+
+    LOG(INFO) << "Finished reading " << blk_count << " blocks on " << blk_device;
+    return true;
+}
+
+static bool verify_image(const std::string& care_map_name) {
+    android::base::unique_fd care_map_fd(TEMP_FAILURE_RETRY(open(care_map_name.c_str(), O_RDONLY)));
+    // If the device is flashed before the current boot, it may not have care_map.txt
+    // in /data/ota_package. To allow the device to continue booting in this situation,
+    // we should print a warning and skip the block verification.
+    if (care_map_fd.get() == -1) {
+        LOG(WARNING) << "Warning: care map " << care_map_name << " not found.";
+        return true;
+    }
+    // Care map file has four lines (two lines if vendor partition is not present):
+    // First line has the block device name, e.g./dev/block/.../by-name/system.
+    // Second line holds all ranges of blocks to verify.
+    // The next two lines have the same format but for vendor partition.
+    std::string file_content;
+    if (!android::base::ReadFdToString(care_map_fd.get(), &file_content)) {
+        LOG(ERROR) << "Error reading care map contents to string.";
+        return false;
+    }
+
+    std::vector<std::string> lines;
+    lines = android::base::Split(android::base::Trim(file_content), "\n");
+    if (lines.size() != 2 && lines.size() != 4) {
+        LOG(ERROR) << "Invalid lines in care_map: found " << lines.size()
+                   << " lines, expecting 2 or 4 lines.";
+        return false;
+    }
+
+    for (size_t i = 0; i < lines.size(); i += 2) {
+        if (!read_blocks(lines[i], lines[i+1])) {
+            return false;
+        }
+    }
+
+    return true;
+}
+
 int main(int argc, char** argv) {
   for (int i = 1; i < argc; i++) {
     LOG(INFO) << "Started with arg " << i << ": " << argv[i];
@@ -59,12 +158,22 @@
 
   if (is_successful == 0) {
     // The current slot has not booted successfully.
-
-    // TODO: Add the actual verification after we have the A/B OTA package
-    // format in place.
-
-    // TODO: Assert the dm-verity mode. Bootloader should never boot a newly
-    // flashed slot (isSlotMarkedSuccessful == 0) with dm-verity logging mode.
+    char verity_mode[PROPERTY_VALUE_MAX];
+    if (property_get("ro.boot.veritymode", verity_mode, "") == -1) {
+      LOG(ERROR) << "Failed to get dm-verity mode.";
+      return -1;
+    } else if (strcasecmp(verity_mode, "eio") == 0) {
+      // We shouldn't see verity in EIO mode if the current slot hasn't booted
+      // successfully before. Therefore, fail the verification when veritymode=eio.
+      LOG(ERROR) << "Found dm-verity in EIO mode, skip verification.";
+      return -1;
+    } else if (strcmp(verity_mode, "enforcing") != 0) {
+      LOG(ERROR) << "Unexpected dm-verity mode : " << verity_mode << ", expecting enforcing.";
+      return -1;
+    } else if (!verify_image(CARE_MAP_FILE)) {
+      LOG(ERROR) << "Failed to verify all blocks in care map file.";
+      return -1;
+    }
 
     int ret = module->markBootSuccessful(module);
     if (ret != 0) {
diff --git a/updater/install.cpp b/updater/install.cpp
index ed55ea5..59c54dd 100644
--- a/updater/install.cpp
+++ b/updater/install.cpp
@@ -95,25 +95,33 @@
     uiPrint(state, error_msg);
 }
 
+static bool is_dir(const std::string& dirpath) {
+  struct stat st;
+  return stat(dirpath.c_str(), &st) == 0 && S_ISDIR(st.st_mode);
+}
+
 // Create all parent directories of name, if necessary.
-static int make_parents(char* name) {
-    char* p;
-    for (p = name + (strlen(name)-1); p > name; --p) {
-        if (*p != '/') continue;
-        *p = '\0';
-        if (make_parents(name) < 0) return -1;
-        int result = mkdir(name, 0700);
-        if (result == 0) printf("created [%s]\n", name);
-        *p = '/';
-        if (result == 0 || errno == EEXIST) {
-            // successfully created or already existed; we're done
-            return 0;
-        } else {
-            printf("failed to mkdir %s: %s\n", name, strerror(errno));
-            return -1;
+static bool make_parents(const std::string& name) {
+    size_t prev_end = 0;
+    while (prev_end < name.size()) {
+        size_t next_end = name.find('/', prev_end + 1);
+        if (next_end == std::string::npos) {
+            break;
         }
+        std::string dir_path = name.substr(0, next_end);
+        if (!is_dir(dir_path)) {
+            int result = mkdir(dir_path.c_str(), 0700);
+            if (result != 0) {
+                printf("failed to mkdir %s when make parents for %s: %s\n", dir_path.c_str(),
+                       name.c_str(), strerror(errno));
+                return false;
+            }
+
+            printf("created [%s]\n", dir_path.c_str());
+        }
+        prev_end = next_end;
     }
-    return 0;
+    return true;
 }
 
 // mount(fs_type, partition_type, location, mount_point)
@@ -342,7 +350,7 @@
         return ErrorAbort(state, kArgsParsingFailure, "%s() Failed to parse the argument(s)", name);
     }
     const std::string& src_name = args[0];
-    std::string& dst_name = args[1];
+    const std::string& dst_name = args[1];
 
     if (src_name.empty()) {
         return ErrorAbort(state, kArgsParsingFailure, "src_name argument to %s() can't be empty",
@@ -352,7 +360,7 @@
         return ErrorAbort(state, kArgsParsingFailure, "dst_name argument to %s() can't be empty",
                           name);
     }
-    if (make_parents(&dst_name[0]) != 0) {
+    if (!make_parents(dst_name)) {
         return ErrorAbort(state, kFileRenameFailure, "Creating parent of %s failed, error %s",
                           dst_name.c_str(), strerror(errno));
     } else if (access(dst_name.c_str(), F_OK) == 0 && access(src_name.c_str(), F_OK) != 0) {
@@ -558,8 +566,9 @@
     }
 }
 
-// symlink target src1 src2 ...
-//    unlinks any previously existing src1, src2, etc before creating symlinks.
+// symlink(target, [src1, src2, ...])
+//   Creates all sources as symlinks to target. It unlinks any previously existing src1, src2, etc
+//   before creating symlinks.
 Value* SymlinkFn(const char* name, State* state, int argc, Expr* argv[]) {
     if (argc == 0) {
         return ErrorAbort(state, kArgsParsingFailure, "%s() expects 1+ args, got %d", name, argc);
@@ -571,33 +580,29 @@
 
     std::vector<std::string> srcs;
     if (!ReadArgs(state, argc-1, argv+1, &srcs)) {
-        return ErrorAbort(state, kArgsParsingFailure, "%s() Failed to parse the argument(s)", name);
+        return ErrorAbort(state, kArgsParsingFailure, "%s(): Failed to parse the argument(s)",
+                          name);
     }
 
-    int bad = 0;
-    for (int i = 0; i < argc-1; ++i) {
-        if (unlink(srcs[i].c_str()) < 0) {
-            if (errno != ENOENT) {
-                printf("%s: failed to remove %s: %s\n",
-                        name, srcs[i].c_str(), strerror(errno));
-                ++bad;
-            }
-        }
-        if (make_parents(&srcs[i][0])) {
+    size_t bad = 0;
+    for (const auto& src : srcs) {
+        if (unlink(src.c_str()) == -1 && errno != ENOENT) {
+            printf("%s: failed to remove %s: %s\n", name, src.c_str(), strerror(errno));
+            ++bad;
+        } else if (!make_parents(src)) {
             printf("%s: failed to symlink %s to %s: making parents failed\n",
-                    name, srcs[i].c_str(), target.c_str());
+                    name, src.c_str(), target.c_str());
             ++bad;
-        }
-        if (symlink(target.c_str(), srcs[i].c_str()) < 0) {
+        } else if (symlink(target.c_str(), src.c_str()) == -1) {
             printf("%s: failed to symlink %s to %s: %s\n",
-                    name, srcs[i].c_str(), target.c_str(), strerror(errno));
+                    name, src.c_str(), target.c_str(), strerror(errno));
             ++bad;
         }
     }
-    if (bad) {
-        return ErrorAbort(state, kSymlinkFailure, "%s: some symlinks failed", name);
+    if (bad != 0) {
+        return ErrorAbort(state, kSymlinkFailure, "%s: Failed to create %zu symlink(s)", name, bad);
     }
-    return StringValue("");
+    return StringValue("t");
 }
 
 struct perm_parsed_args {