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authorEthan Yonker <dees_troy@teamw.in>2017-09-08 13:50:54 +0200
committerEthan Yonker <dees_troy@teamw.in>2017-09-08 14:14:59 +0200
commit8373cfe28cf1b5ad758faa1d502e21787c3665e4 (patch)
tree2f567c52cd6f89e1052481497d236b58d230b7e2 /bootloader_message_twrp
parentDO NOT MERGE Android 8.0 stuff (diff)
parentrelease-request-f4ecf242-5d1c-45e0-8c7c-ede48d1a9e82-for-git_oc-release-4111650 snap-temp-L02200000075283731 (diff)
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Diffstat (limited to 'bootloader_message_twrp')
-rw-r--r--bootloader_message_twrp/Android.mk35
-rw-r--r--bootloader_message_twrp/bootloader_message.cpp386
-rw-r--r--bootloader_message_twrp/include/bootloader_message_twrp/bootloader_message.h236
3 files changed, 657 insertions, 0 deletions
diff --git a/bootloader_message_twrp/Android.mk b/bootloader_message_twrp/Android.mk
new file mode 100644
index 000000000..5a24dc43f
--- /dev/null
+++ b/bootloader_message_twrp/Android.mk
@@ -0,0 +1,35 @@
+# 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.
+
+LOCAL_PATH := $(call my-dir)
+
+include $(CLEAR_VARS)
+LOCAL_CLANG := true
+LOCAL_SRC_FILES := bootloader_message.cpp
+LOCAL_MODULE := libbootloader_message_twrp
+LOCAL_C_INCLUDES += bionic $(LOCAL_PATH)/include
+ifeq ($(shell test $(PLATFORM_SDK_VERSION) -lt 22; echo $$?),0)
+ LOCAL_C_INCLUDES += external/stlport/stlport
+ LOCAL_SHARED_LIBRARIES += libstlport
+else
+ LOCAL_C_INCLUDES += external/libcxx/include
+ LOCAL_SHARED_LIBRARIES += libc++
+endif
+LOCAL_CFLAGS := -Werror -std=c++11
+# ignore bootloader's factory reset command even when written to /misc
+ifeq ($(TW_IGNORE_MISC_WIPE_DATA), true)
+ LOCAL_CFLAGS += -DIGNORE_MISC_WIPE_DATA
+endif
+LOCAL_EXPORT_C_INCLUDE_DIRS := $(LOCAL_PATH)/include
+include $(BUILD_SHARED_LIBRARY)
diff --git a/bootloader_message_twrp/bootloader_message.cpp b/bootloader_message_twrp/bootloader_message.cpp
new file mode 100644
index 000000000..55d3a5d9e
--- /dev/null
+++ b/bootloader_message_twrp/bootloader_message.cpp
@@ -0,0 +1,386 @@
+/*
+ * 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 <bootloader_message_twrp/bootloader_message.h>
+
+#include <errno.h>
+#include <fcntl.h>
+#include <string.h>
+#include <stdlib.h>
+#include <sys/stat.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/system_properties.h>
+
+#include <string>
+#include <vector>
+
+static std::string misc_blkdev;
+
+void set_misc_device(const char* name) {
+ misc_blkdev = name;
+}
+
+static std::string get_misc_blk_device(std::string* err) {
+ *err = "";
+ return misc_blkdev;
+}
+
+// In recovery mode, recovery can get started and try to access the misc
+// device before the kernel has actually created it.
+static bool wait_for_device(const std::string& blk_device, std::string* err) {
+ int tries = 0;
+ int ret;
+ err->clear();
+ do {
+ ++tries;
+ struct stat buf;
+ ret = stat(blk_device.c_str(), &buf);
+ if (ret == -1) {
+ char buffer[2048];
+ sprintf(buffer, "failed to stat %s try %d: %s\n",
+ blk_device.c_str(), tries, strerror(errno));
+ *err += buffer;
+ /*
+ *err += android::base::StringPrintf("failed to stat %s try %d: %s\n",
+ blk_device.c_str(), tries, strerror(errno));
+ */
+ sleep(1);
+ }
+ } while (ret && tries < 10);
+
+ if (ret) {
+ *err += "failed to stat " + blk_device + "\n";
+ /*
+ *err += android::base::StringPrintf("failed to stat %s\n", blk_device.c_str());
+ */
+ }
+ return ret == 0;
+}
+
+static bool read_misc_partition(void* p, size_t size, const std::string& misc_blk_device,
+ size_t offset, std::string* err) {
+ if (!wait_for_device(misc_blk_device, err)) {
+ return false;
+ }
+
+ int fd(open(misc_blk_device.c_str(), O_RDONLY));
+ if (fd < 0) {
+ *err = "failed to open " + misc_blk_device + ": ";
+ *err += strerror(errno);
+ /*
+ android::base::unique_fd fd(open(misc_blk_device.c_str(), O_RDONLY));
+ if (fd == -1) {
+ *err = android::base::StringPrintf("failed to open %s: %s", misc_blk_device.c_str(),
+ strerror(errno));
+ */
+ return false;
+ }
+ if (lseek(fd, static_cast<off_t>(offset), SEEK_SET) != static_cast<off_t>(offset)) {
+ *err = "failed to lseek " + misc_blk_device + ": ";
+ *err += strerror(errno);
+ close(fd);
+ /*
+
+ *err = android::base::StringPrintf("failed to lseek %s: %s", misc_blk_device.c_str(),
+ strerror(errno));
+ */
+ return false;
+ }
+
+ if ((size_t)read(fd, p, size) != size) {
+ *err = "failed to read " + misc_blk_device + ": ";
+ *err += strerror(errno);
+ close(fd);
+ /*
+ if (!android::base::ReadFully(fd, p, size)) {
+ *err = android::base::StringPrintf("failed to read %s: %s", misc_blk_device.c_str(),
+ strerror(errno));
+ */
+ return false;
+ }
+ close(fd);
+ return true;
+}
+
+static bool write_misc_partition(const void* p, size_t size, size_t offset, std::string* err) {
+ std::string misc_blk_device = get_misc_blk_device(err);
+ if (misc_blk_device.empty()) {
+ *err = "no misc device set";
+ return false;
+ }
+ int fd = (open(misc_blk_device.c_str(), O_WRONLY | O_SYNC));
+ if (fd == -1) {
+ *err = "failed to open " + misc_blk_device + ": ";
+ *err += strerror(errno);
+ /*
+static bool write_misc_partition(const void* p, size_t size, const std::string& misc_blk_device,
+ size_t offset, std::string* err) {
+ android::base::unique_fd fd(open(misc_blk_device.c_str(), O_WRONLY));
+ if (fd == -1) {
+ *err = android::base::StringPrintf("failed to open %s: %s", misc_blk_device.c_str(),
+ strerror(errno));
+ */
+ return false;
+ }
+ if (lseek(fd, static_cast<off_t>(offset), SEEK_SET) != static_cast<off_t>(offset)) {
+ *err = "failed to lseek " + misc_blk_device + ": ";
+ *err += strerror(errno);
+ close(fd);
+ /*
+ *err = android::base::StringPrintf("failed to lseek %s: %s", misc_blk_device.c_str(),
+ strerror(errno));
+ */
+ return false;
+ }
+ if ((size_t)write(fd, p, size) != size) {
+ *err = "failed to write " + misc_blk_device + ": ";
+ *err += strerror(errno);
+ close(fd);
+ /*
+ if (!android::base::WriteFully(fd, p, size)) {
+ *err = android::base::StringPrintf("failed to write %s: %s", misc_blk_device.c_str(),
+ strerror(errno));
+ */
+ return false;
+ }
+
+ // TODO: O_SYNC and fsync duplicates each other?
+ if (fsync(fd) == -1) {
+ *err = "failed to fsync " + misc_blk_device + ": ";
+ *err += strerror(errno);
+ close(fd);
+ /*
+ if (fsync(fd) == -1) {
+ *err = android::base::StringPrintf("failed to fsync %s: %s", misc_blk_device.c_str(),
+ strerror(errno));
+ */
+ return false;
+ }
+ close(fd);
+ return true;
+}
+
+bool read_bootloader_message_from(bootloader_message* boot, const std::string& misc_blk_device,
+ std::string* err) {
+ return read_misc_partition(boot, sizeof(*boot), misc_blk_device,
+ BOOTLOADER_MESSAGE_OFFSET_IN_MISC, err);
+}
+
+bool read_bootloader_message(bootloader_message* boot, std::string* err) {
+ std::string misc_blk_device = get_misc_blk_device(err);
+ if (misc_blk_device.empty()) {
+ return false;
+ }
+ return read_bootloader_message_from(boot, misc_blk_device, err);
+}
+
+bool write_bootloader_message_to(const bootloader_message& boot, __unused const std::string& misc_blk_device,
+ std::string* err) {
+ return write_misc_partition(&boot, sizeof(boot),
+ BOOTLOADER_MESSAGE_OFFSET_IN_MISC, err);
+}
+
+bool write_bootloader_message(const bootloader_message& boot, std::string* err) {
+ std::string misc_blk_device = get_misc_blk_device(err);
+ if (misc_blk_device.empty()) {
+ return false;
+ }
+ return write_bootloader_message_to(boot, misc_blk_device, err);
+}
+
+// libc++ in 5.1 does not know how to handle a std::string* so this craziness is needed
+bool clear_bootloader_message(void* err) {
+ std::string &s = *(static_cast<std::string*>(err));
+ return clear_bootloader_message(&s);
+}
+
+bool clear_bootloader_message(std::string* err) {
+ bootloader_message boot = {};
+ return write_bootloader_message(boot, err);
+}
+
+bool write_bootloader_message(const std::vector<std::string>& options, std::string* err) {
+ bootloader_message boot = {};
+ strlcpy(boot.command, "boot-recovery", sizeof(boot.command));
+ strlcpy(boot.recovery, "recovery\n", sizeof(boot.recovery));
+ for (const auto& s : options) {
+ strlcat(boot.recovery, s.c_str(), sizeof(boot.recovery));
+ if (s.substr(s.size() - 1) != "\n") {
+ strlcat(boot.recovery, "\n", sizeof(boot.recovery));
+ }
+ }
+ return write_bootloader_message(boot, err);
+}
+
+bool update_bootloader_message(const std::vector<std::string>& options, std::string* err) {
+ bootloader_message boot;
+ if (!read_bootloader_message(&boot, err)) {
+ return false;
+ }
+
+ // Zero out the entire fields.
+ memset(boot.command, 0, sizeof(boot.command));
+ memset(boot.recovery, 0, sizeof(boot.recovery));
+
+ strlcpy(boot.command, "boot-recovery", sizeof(boot.command));
+ strlcpy(boot.recovery, "recovery\n", sizeof(boot.recovery));
+ for (const auto& s : options) {
+ strlcat(boot.recovery, s.c_str(), sizeof(boot.recovery));
+ if (s.back() != '\n') {
+ strlcat(boot.recovery, "\n", sizeof(boot.recovery));
+ }
+ }
+ 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) {
+ std::string misc_blk_device = get_misc_blk_device(err);
+ if (misc_blk_device.empty()) {
+ return false;
+ }
+ package_data->resize(size);
+ return read_misc_partition(&(*package_data)[0], size, misc_blk_device,
+ WIPE_PACKAGE_OFFSET_IN_MISC, err);
+}
+
+bool write_wipe_package(const std::string& package_data, std::string* err) {
+ std::string misc_blk_device = get_misc_blk_device(err);
+ if (misc_blk_device.empty()) {
+ return false;
+ }
+ return write_misc_partition(package_data.data(), package_data.size(),
+ 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;
+ bootloader_message boot = {};
+ memcpy(&boot, options, sizeof(boot));
+ return write_bootloader_message(boot, &err);
+}
+
+static const char *COMMAND_FILE = "/cache/recovery/command";
+static const int MAX_ARG_LENGTH = 4096;
+static const int MAX_ARGS = 100;
+
+// command line args come from, in decreasing precedence:
+// - the actual command line
+// - the bootloader control block (one per line, after "recovery")
+// - the contents of COMMAND_FILE (one per line)
+void
+get_args(int *argc, char ***argv) {
+ bootloader_message boot = {};
+ std::string err;
+ if (!read_bootloader_message(&boot, &err)) {
+ printf("%s\n", err.c_str());
+ // If fails, leave a zeroed bootloader_message.
+ memset(&boot, 0, sizeof(boot));
+ }
+ //stage = strndup(boot.stage, sizeof(boot.stage));
+
+ if (boot.command[0] != 0 && boot.command[0] != 255) {
+ printf("Boot command: %.*s\n", (int)sizeof(boot.command), boot.command);
+ }
+
+ if (boot.status[0] != 0 && boot.status[0] != 255) {
+ printf("Boot status: %.*s\n", (int)sizeof(boot.status), boot.status);
+ }
+
+ // --- if arguments weren't supplied, look in the bootloader control block
+ if (*argc <= 1) {
+ boot.recovery[sizeof(boot.recovery) - 1] = '\0'; // Ensure termination
+ const char *arg = strtok(boot.recovery, "\n");
+ if (arg != NULL && !strcmp(arg, "recovery")) {
+ *argv = (char **) malloc(sizeof(char *) * MAX_ARGS);
+ (*argv)[0] = strdup(arg);
+ for (*argc = 1; *argc < MAX_ARGS; ++*argc) {
+ if ((arg = strtok(NULL, "\n")) == NULL) break;
+
+// if the device does not have an own recovery key combo we just want to open TWRP after
+// walking through the factory reset screen - without actually doing a factory reset
+#ifdef IGNORE_MISC_WIPE_DATA
+ if (!strcmp(arg, "--wipe_data")) {
+ (*argv)[*argc] = "";
+ *argc = *argc -1;
+ printf("Bootloader arg \"%s\" ignored because TWRP was compiled with TW_IGNORE_MISC_WIPE_DATA\n", arg);
+ continue;
+ }
+#endif
+ (*argv)[*argc] = strdup(arg);
+ }
+ printf("Got arguments from boot message\n");
+ } else if (boot.recovery[0] != 0 && boot.recovery[0] != 255) {
+ printf("Bad boot message\n\"%.20s\"\n", boot.recovery);
+ }
+ }
+
+ // --- if that doesn't work, try the command file (if we have /cache).
+ if (*argc <= 1/* && has_cache*/) {
+ FILE *fp = fopen(COMMAND_FILE, "r");
+ if (fp != NULL) {
+ char *token;
+ char *argv0 = (*argv)[0];
+ *argv = (char **) malloc(sizeof(char *) * MAX_ARGS);
+ (*argv)[0] = argv0; // use the same program name
+
+ char buf[MAX_ARG_LENGTH];
+ for (*argc = 1; *argc < MAX_ARGS; ++*argc) {
+ if (!fgets(buf, sizeof(buf), fp)) break;
+ token = strtok(buf, "\r\n");
+ if (token != NULL) {
+ (*argv)[*argc] = strdup(token); // Strip newline.
+ } else {
+ --*argc;
+ }
+ }
+
+ fclose(fp);
+ printf("Got arguments from %s\n", COMMAND_FILE);
+ }
+ }
+
+ // --> write the arguments we have back into the bootloader control block
+ // always boot into recovery after this (until finish_recovery() is called)
+ strlcpy(boot.command, "boot-recovery", sizeof(boot.command));
+ strlcpy(boot.recovery, "recovery\n", sizeof(boot.recovery));
+ int i;
+ for (i = 1; i < *argc; ++i) {
+ strlcat(boot.recovery, (*argv)[i], sizeof(boot.recovery));
+ strlcat(boot.recovery, "\n", sizeof(boot.recovery));
+ }
+ if (!write_bootloader_message(boot, &err)) {
+ printf("%s\n", err.c_str());
+ }
+}
diff --git a/bootloader_message_twrp/include/bootloader_message_twrp/bootloader_message.h b/bootloader_message_twrp/include/bootloader_message_twrp/bootloader_message.h
new file mode 100644
index 000000000..52c1b86f0
--- /dev/null
+++ b/bootloader_message_twrp/include/bootloader_message_twrp/bootloader_message.h
@@ -0,0 +1,236 @@
+/*
+ * Copyright (C) 2008 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 _BOOTLOADER_MESSAGE_TWRP_H
+#define _BOOTLOADER_MESSAGE_TWRP_H
+
+#include <assert.h>
+#include <stddef.h>
+#include <stdint.h>
+
+// Spaces used by misc partition are as below:
+// 0 - 2K For bootloader_message
+// 2K - 16K Used by Vendor's bootloader (the 2K - 4K range may be optionally used
+// as bootloader_message_ab struct)
+// 16K - 64K Used by uncrypt and recovery to store wipe_package for A/B devices
+// Note that these offsets are admitted by bootloader,recovery and uncrypt, so they
+// are not configurable without changing all of them.
+#ifdef BOARD_RECOVERY_BLDRMSG_OFFSET
+static const size_t BOOTLOADER_MESSAGE_OFFSET_IN_MISC = BOARD_RECOVERY_BLDRMSG_OFFSET;
+static const size_t WIPE_PACKAGE_OFFSET_IN_MISC = 16 * 1024 + BOOTLOADER_MESSAGE_OFFSET_IN_MISC;
+#else
+static const size_t BOOTLOADER_MESSAGE_OFFSET_IN_MISC = 0;
+static const size_t WIPE_PACKAGE_OFFSET_IN_MISC = 16 * 1024;
+#endif
+
+/* Bootloader Message (2-KiB)
+ *
+ * This structure describes the content of a block in flash
+ * that is used for recovery and the bootloader to talk to
+ * each other.
+ *
+ * The command field is updated by linux when it wants to
+ * reboot into recovery or to update radio or bootloader firmware.
+ * It is also updated by the bootloader when firmware update
+ * is complete (to boot into recovery for any final cleanup)
+ *
+ * The status field was used by the bootloader after the completion
+ * of an "update-radio" or "update-hboot" command, which has been
+ * deprecated since Froyo.
+ *
+ * The recovery field is only written by linux and used
+ * for the system to send a message to recovery or the
+ * other way around.
+ *
+ * The stage field is written by packages which restart themselves
+ * multiple times, so that the UI can reflect which invocation of the
+ * package it is. If the value is of the format "#/#" (eg, "1/3"),
+ * the UI will add a simple indicator of that status.
+ *
+ * We used to have slot_suffix field for A/B boot control metadata in
+ * this struct, which gets unintentionally cleared by recovery or
+ * uncrypt. Move it into struct bootloader_message_ab to avoid the
+ * issue.
+ */
+struct bootloader_message {
+ char command[32];
+ char status[32];
+ char recovery[768];
+
+ // The 'recovery' field used to be 1024 bytes. It has only ever
+ // been used to store the recovery command line, so 768 bytes
+ // should be plenty. We carve off the last 256 bytes to store the
+ // stage string (for multistage packages) and possible future
+ // expansion.
+ char stage[32];
+
+ // The 'reserved' field used to be 224 bytes when it was initially
+ // carved off from the 1024-byte recovery field. Bump it up to
+ // 1184-byte so that the entire bootloader_message struct rounds up
+ // to 2048-byte.
+ char reserved[1184];
+};
+
+/**
+ * We must be cautious when changing the bootloader_message struct size,
+ * because A/B-specific fields may end up with different offsets.
+ */
+/*#if (__STDC_VERSION__ >= 201112L) || defined(__cplusplus)
+static_assert(sizeof(struct bootloader_message) == 2048,
+ "struct bootloader_message size changes, which may break A/B devices");
+#endif*/
+
+/**
+ * The A/B-specific bootloader message structure (4-KiB).
+ *
+ * We separate A/B boot control metadata from the regular bootloader
+ * message struct and keep it here. Everything that's A/B-specific
+ * stays after struct bootloader_message, which should be managed by
+ * the A/B-bootloader or boot control HAL.
+ *
+ * The slot_suffix field is used for A/B implementations where the
+ * bootloader does not set the androidboot.ro.boot.slot_suffix kernel
+ * commandline parameter. This is used by fs_mgr to mount /system and
+ * other partitions with the slotselect flag set in fstab. A/B
+ * implementations are free to use all 32 bytes and may store private
+ * data past the first NUL-byte in this field. It is encouraged, but
+ * not mandatory, to use 'struct bootloader_control' described below.
+ */
+struct bootloader_message_ab {
+ struct bootloader_message message;
+ char slot_suffix[32];
+
+ // Round up the entire struct to 4096-byte.
+ char reserved[2016];
+};
+
+/**
+ * Be cautious about the struct size change, in case we put anything post
+ * bootloader_message_ab struct (b/29159185).
+ */
+/*#if (__STDC_VERSION__ >= 201112L) || defined(__cplusplus)
+static_assert(sizeof(struct bootloader_message_ab) == 4096,
+ "struct bootloader_message_ab size changes");
+#endif*/
+
+#define BOOT_CTRL_MAGIC 0x42414342 /* Bootloader Control AB */
+#define BOOT_CTRL_VERSION 1
+
+struct slot_metadata {
+ // Slot priority with 15 meaning highest priority, 1 lowest
+ // priority and 0 the slot is unbootable.
+ uint8_t priority : 4;
+ // Number of times left attempting to boot this slot.
+ uint8_t tries_remaining : 3;
+ // 1 if this slot has booted successfully, 0 otherwise.
+ uint8_t successful_boot : 1;
+ // 1 if this slot is corrupted from a dm-verity corruption, 0
+ // otherwise.
+ uint8_t verity_corrupted : 1;
+ // Reserved for further use.
+ uint8_t reserved : 7;
+} __attribute__((packed));
+
+/* Bootloader Control AB
+ *
+ * This struct can be used to manage A/B metadata. It is designed to
+ * be put in the 'slot_suffix' field of the 'bootloader_message'
+ * structure described above. It is encouraged to use the
+ * 'bootloader_control' structure to store the A/B metadata, but not
+ * mandatory.
+ */
+struct bootloader_control {
+ // NUL terminated active slot suffix.
+ char slot_suffix[4];
+ // Bootloader Control AB magic number (see BOOT_CTRL_MAGIC).
+ uint32_t magic;
+ // Version of struct being used (see BOOT_CTRL_VERSION).
+ uint8_t version;
+ // Number of slots being managed.
+ uint8_t nb_slot : 3;
+ // Number of times left attempting to boot recovery.
+ uint8_t recovery_tries_remaining : 3;
+ // Ensure 4-bytes alignment for slot_info field.
+ uint8_t reserved0[2];
+ // Per-slot information. Up to 4 slots.
+ struct slot_metadata slot_info[4];
+ // Reserved for further use.
+ uint8_t reserved1[8];
+ // CRC32 of all 28 bytes preceding this field (little endian
+ // format).
+ uint32_t crc32_le;
+} __attribute__((packed));
+
+/*#if (__STDC_VERSION__ >= 201112L) || defined(__cplusplus)
+static_assert(sizeof(struct bootloader_control) ==
+ sizeof(((struct bootloader_message_ab *)0)->slot_suffix),
+ "struct bootloader_control has wrong size");
+#endif*/
+
+#ifdef __cplusplus
+
+#include <string.h>
+#include <vector>
+
+// Read bootloader message into boot. Error message will be set in err.
+bool read_bootloader_message(bootloader_message* boot, std::string* err);
+
+// Read bootloader message from the specified misc device into boot.
+bool read_bootloader_message_from(bootloader_message* boot, const std::string& misc_blk_device,
+ std::string* err);
+
+// Write bootloader message to BCB.
+bool write_bootloader_message(const bootloader_message& boot, std::string* err);
+
+// Write bootloader message to the specified BCB device.
+bool write_bootloader_message_to(const bootloader_message& boot,
+ const std::string& misc_blk_device, std::string* err);
+
+// Write bootloader message (boots into recovery with the options) to BCB. Will
+// set the command and recovery fields, and reset the rest.
+bool write_bootloader_message(const std::vector<std::string>& options, std::string* err);
+
+// Update bootloader message (boots into recovery with the options) to BCB. Will
+// only update the command and recovery fields.
+bool update_bootloader_message(const std::vector<std::string>& options, std::string* err);
+
+// Clear BCB.
+bool clear_bootloader_message(void* 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);
+
+// Read the wipe package from BCB (from offset WIPE_PACKAGE_OFFSET_IN_MISC).
+bool read_wipe_package(std::string* package_data, size_t size, std::string* err);
+
+void set_misc_device(const char* name);
+void get_args(int *argc, char ***argv);
+
+// Write the wipe package into BCB (to offset WIPE_PACKAGE_OFFSET_IN_MISC).
+bool write_wipe_package(const std::string& package_data, std::string* err);
+
+#else
+
+#include <stdbool.h>
+
+// C Interface.
+bool write_bootloader_message(const char* options);
+bool write_reboot_bootloader(void);
+
+#endif // ifdef __cplusplus
+
+#endif // _BOOTLOADER_MESSAGE_TWRP_H