這篇及之後的篇幅將經過分析update.zip包在具體Android系統升級的過程,來理解Android系統中Recovery模式服務的工做原理。咱們先從update.zip包的製做開始,而後是Android系統的啓動模式分析,Recovery工做原理,如何從咱們上層開始選擇system update到重啓到Recovery服務,以及在Recovery服務中具體怎樣處理update.zip包升級的,咱們的安裝腳本updater-script怎樣被解析並執行的等一系列問題。分析過程當中所用的Android源碼是gingerbread0919(tcc88xx開發板標配的),測試開發板是tcc88xx。這是在工做中總結的文檔,固然在網上參考了很多內容,若有雷同純屬巧合吧,在分析過程當中也存在不少未解決的問題,也但願你們不吝指教。node
1、
update.zip包的目錄結構
|----boot.img
|----system/
|----recovery/
`|----recovery-from-boot.p
`|----etc/
`|----install-recovery.sh
|---META-INF/
`|CERT.RSA
`|CERT.SF
`|MANIFEST.MF
`|----com/
`|----google/
`|----android/
`|----update-binary
`|----updater-script
`|----android/
`|----metadata
2、
update.zip包目錄結構詳解
以上是咱們用命令make otapackage 製做的update.zip包的標準目錄結構。
一、boot.img是更新boot分區所須要的文件。這個boot.img主要包括kernel+ramdisk。
二、system/目錄的內容在升級後會放在系統的system分區。主要用來更新系統的一些應用或則應用會用到的一些庫等等。能夠將Android源碼編譯out/target/product/tcc8800/system/中的全部文件拷貝到這個目錄來代替。python
三、recovery/目錄中的recovery-from-boot.p是boot.img和recovery.img的補丁(patch),主要用來更新recovery分區,其中etc/目錄下的install-recovery.sh是更新腳本。
四、update-binary是一個二進制文件,至關於一個腳本解釋器,可以識別updater-script中描述的操做。該文件在Android源碼編譯後out/target/product/tcc8800/system bin/updater生成,可將updater重命名爲update-binary獲得。
該文件在具體的更新包中的名字由源碼中bootable/recovery/install.c中的宏ASSUMED_UPDATE_BINARY_NAME的值而定。
五、updater-script:此文件是一個腳本文件,具體描述了更新過程。咱們能夠根據具體狀況編寫該腳原本適應咱們的具體需求。該文件的命名由源碼中bootable/recovery/updater/updater.c文件中的宏SCRIPT_NAME的值而定。
六、 metadata文件是描述設備信息及環境變量的元數據。主要包括一些編譯選項,簽名公鑰,時間戳以及設備型號等。
七、咱們還能夠在包中添加userdata目錄,來更新系統中的用戶數據部分。這部份內容在更新後會存放在系統的/data目錄下。
八、update.zip包的簽名:update.zip更新包在製做完成後須要對其簽名,不然在升級時會出現認證失敗的錯誤提示。並且簽名要使用和目標板一致的加密公鑰。加密公鑰及加密須要的三個文件在Android源碼編譯後生成的具體路徑爲:linux
out/host/Linux-x86/framework/signapk.jar android
build/target/product/security/testkey.x509.pem git
build/target/product/security/testkey.pk8 。shell
咱們用命令make otapackage製做生成的update.zip包是已簽過名的,若是本身作update.zip包時必須手動對其簽名。express
具體的加密方法:$ java –jar gingerbread/out/host/linux/framework/signapk.jar –w gingerbread/build/target/product/security/testkey.x509.pem gingerbread/build/target/product/security/testkey.pk8 update.zip update_signed.zip
以上命令在update.zip包所在的路徑下執行,其中signapk.jar testkey.x509.pem以及testkey.pk8文件的引用使用絕對路徑。update.zip 是咱們已經打好的包,update_signed.zip包是命令執行完生成的已經簽過名的包。
九、MANIFEST.MF:這個manifest文件定義了與包的組成結構相關的數據。相似Android應用的mainfest.xml文件。
十、CERT.RSA:與簽名文件相關聯的簽名程序塊文件,它存儲了用於簽名JAR文件的公共簽名。
十一、CERT.SF:這是JAR文件的簽名文件,其中前綴CERT表明簽名者。
另外,在具體升級時,對update.zip包檢查時大體會分三步:①檢驗SF文件與RSA文件是否匹配。②檢驗MANIFEST.MF與簽名文件中的digest是否一致。③檢驗包中的文件與MANIFEST中所描述的是否一致。
3、
Android升級包update.zip的生成過程分析
1) 對於update.zip包的製做有兩種方式,即手動製做和命令生成。apache
第一種手動製做:即按照update.zip的目錄結構手動建立咱們須要的目錄。而後將對應的文件拷貝到相應的目錄下,好比咱們向系統中新加一個應用程序。能夠將新增的應用拷貝到咱們新建的update/system/app/下(system目錄是事先拷貝編譯源碼後生成的system目錄),打包並簽名後,拷貝到SD卡就可使用了。這種方式在實際的tcc8800開發板中未測試成功。簽名部分未經過,可能與具體的開發板相關。api
第二種製做方式:命令製做。Android源碼系統中爲咱們提供了製做update.zip刷機包的命令,即make otapackage。該命令在編譯源碼完成後並在源碼根目錄下執行。 具體操做方式:在源碼根目錄下執行
①$ . build/envsetup.sh。
②$ lunch 而後選擇你須要的配置(如17)。
③$ make otapackage。
在編譯完源碼後最好再執行一遍上面的①、②步防止執行③時出現未找到對應規則的錯誤提示。命令執行完成後生成的升級包所在位置在out/target/product/full_tcc8800_evm_target_files-eng.mumu.20120309.111059.zip將這個包從新命名爲update.zip,並拷貝到SD卡中便可使用。
這種方式(即徹底升級)在tcc8800開發板中已測試成功。
2) 使用make otapackage命令生成update.zip的過程分析。
在源碼根目錄下執行make otapackage命令生成update.zip包主要分爲兩步,第一步是根據Makefile執行編譯生成一個update原包(zip格式)。第二步是運行一個python腳本,並以上一步準備的zip包做爲輸入,最終生成咱們須要的升級包。下面進一步分析這兩個過程。
第一步:編譯Makefile。對應的Makefile文件所在位置:build/core/Makefile。從該文件的884行(tcc8800,gingerbread0919)開始會生成一個zip包,這個包最後會用來製做OTA package 或者filesystem image。先將這部分的對應的Makefile貼出來以下:
- # -----------------------------------------------------------------
- # A zip of the directories that map to the target filesystem.
- # This zip can be used to create an OTA package or filesystem image
- # as a post-build step.
- #
- name := $(TARGET_PRODUCT)
- ifeq ($(TARGET_BUILD_TYPE),debug)
- name := $(name)_debug
- endif
- name := $(name)-target_files-$(FILE_NAME_TAG)
-
- intermediates := $(call intermediates-dir-for,PACKAGING,target_files)
- BUILT_TARGET_FILES_PACKAGE := $(intermediates)/$(name).zip
- $(BUILT_TARGET_FILES_PACKAGE): intermediates := $(intermediates)
- $(BUILT_TARGET_FILES_PACKAGE): \
- zip_root := $(intermediates)/$(name)
-
- # $(1): Directory to copy
- # $(2): Location to copy it to
- # The "ls -A" is to prevent "acp s/* d" from failing if s is empty.
- define package_files-copy-root
- if [ -d "$(strip $(1))" -a "$$(ls -A $(1))" ]; then \
- mkdir -p $(2) && \
- $(ACP) -rd $(strip $(1))/* $(2); \
- fi
- endef
-
- built_ota_tools := \
- $(call intermediates-dir-for,EXECUTABLES,applypatch)/applypatch \
- $(call intermediates-dir-for,EXECUTABLES,applypatch_static)/applypatch_static \
- $(call intermediates-dir-for,EXECUTABLES,check_prereq)/check_prereq \
- $(call intermediates-dir-for,EXECUTABLES,updater)/updater
- $(BUILT_TARGET_FILES_PACKAGE): PRIVATE_OTA_TOOLS := $(built_ota_tools)
-
- $(BUILT_TARGET_FILES_PACKAGE): PRIVATE_RECOVERY_API_VERSION := $(RECOVERY_API_VERSION)
-
- ifeq ($(TARGET_RELEASETOOLS_EXTENSIONS),)
- # default to common dir for device vendor
- $(BUILT_TARGET_FILES_PACKAGE): tool_extensions := $(TARGET_DEVICE_DIR)/../common
- else
- $(BUILT_TARGET_FILES_PACKAGE): tool_extensions := $(TARGET_RELEASETOOLS_EXTENSIONS)
- endif
-
- # Depending on the various images guarantees that the underlying
- # directories are up-to-date.
- $(BUILT_TARGET_FILES_PACKAGE): \
- $(INSTALLED_BOOTIMAGE_TARGET) \
- $(INSTALLED_RADIOIMAGE_TARGET) \
- $(INSTALLED_RECOVERYIMAGE_TARGET) \
- $(INSTALLED_SYSTEMIMAGE) \
- $(INSTALLED_USERDATAIMAGE_TARGET) \
- $(INSTALLED_ANDROID_INFO_TXT_TARGET) \
- $(built_ota_tools) \
- $(APKCERTS_FILE) \
- $(HOST_OUT_EXECUTABLES)/fs_config \
- | $(ACP)
- @echo "Package target files: $@"
- $(hide) rm -rf $@ $(zip_root)
- $(hide) mkdir -p $(dir $@) $(zip_root)
- @# Components of the recovery image
- $(hide) mkdir -p $(zip_root)/RECOVERY
- $(hide) $(call package_files-copy-root, \
- $(TARGET_RECOVERY_ROOT_OUT),$(zip_root)/RECOVERY/RAMDISK)
- ifdef INSTALLED_KERNEL_TARGET
- $(hide) $(ACP) $(INSTALLED_KERNEL_TARGET) $(zip_root)/RECOVERY/kernel
- endif
- ifdef INSTALLED_2NDBOOTLOADER_TARGET
- $(hide) $(ACP) \
- $(INSTALLED_2NDBOOTLOADER_TARGET) $(zip_root)/RECOVERY/second
- endif
- ifdef BOARD_KERNEL_CMDLINE
- $(hide) echo "$(BOARD_KERNEL_CMDLINE)" > $(zip_root)/RECOVERY/cmdline
- endif
- ifdef BOARD_KERNEL_BASE
- $(hide) echo "$(BOARD_KERNEL_BASE)" > $(zip_root)/RECOVERY/base
- endif
- ifdef BOARD_KERNEL_PAGESIZE
- $(hide) echo "$(BOARD_KERNEL_PAGESIZE)" > $(zip_root)/RECOVERY/pagesize
- endif
- @# Components of the boot image
- $(hide) mkdir -p $(zip_root)/BOOT
- $(hide) $(call package_files-copy-root, \
- $(TARGET_ROOT_OUT),$(zip_root)/BOOT/RAMDISK)
- ifdef INSTALLED_KERNEL_TARGET
- $(hide) $(ACP) $(INSTALLED_KERNEL_TARGET) $(zip_root)/BOOT/kernel
- endif
- ifdef INSTALLED_2NDBOOTLOADER_TARGET
- $(hide) $(ACP) \
- $(INSTALLED_2NDBOOTLOADER_TARGET) $(zip_root)/BOOT/second
- endif
- ifdef BOARD_KERNEL_CMDLINE
- $(hide) echo "$(BOARD_KERNEL_CMDLINE)" > $(zip_root)/BOOT/cmdline
- endif
- ifdef BOARD_KERNEL_BASE
- $(hide) echo "$(BOARD_KERNEL_BASE)" > $(zip_root)/BOOT/base
- endif
- ifdef BOARD_KERNEL_PAGESIZE
- $(hide) echo "$(BOARD_KERNEL_PAGESIZE)" > $(zip_root)/BOOT/pagesize
- endif
- $(hide) $(foreach t,$(INSTALLED_RADIOIMAGE_TARGET),\
- mkdir -p $(zip_root)/RADIO; \
- $(ACP) $(t) $(zip_root)/RADIO/$(notdir $(t));)
- @# Contents of the system image
- $(hide) $(call package_files-copy-root, \
- $(SYSTEMIMAGE_SOURCE_DIR),$(zip_root)/SYSTEM)
- @# Contents of the data image
- $(hide) $(call package_files-copy-root, \
- $(TARGET_OUT_DATA),$(zip_root)/DATA)
- @# Extra contents of the OTA package
- $(hide) mkdir -p $(zip_root)/OTA/bin
- $(hide) $(ACP) $(INSTALLED_ANDROID_INFO_TXT_TARGET) $(zip_root)/OTA/
- $(hide) $(ACP) $(PRIVATE_OTA_TOOLS) $(zip_root)/OTA/bin/
- @# Files that do not end up in any images, but are necessary to
- @# build them.
- $(hide) mkdir -p $(zip_root)/META
- $(hide) $(ACP) $(APKCERTS_FILE) $(zip_root)/META/apkcerts.txt
- $(hide) echo "$(PRODUCT_OTA_PUBLIC_KEYS)" > $(zip_root)/META/otakeys.txt
- $(hide) echo "recovery_api_version=$(PRIVATE_RECOVERY_API_VERSION)" > $(zip_root)/META/misc_info.txt
- ifdef BOARD_FLASH_BLOCK_SIZE
- $(hide) echo "blocksize=$(BOARD_FLASH_BLOCK_SIZE)" >> $(zip_root)/META/misc_info.txt
- endif
- ifdef BOARD_BOOTIMAGE_PARTITION_SIZE
- $(hide) echo "boot_size=$(BOARD_BOOTIMAGE_PARTITION_SIZE)" >> $(zip_root)/META/misc_info.txt
- endif
- ifdef BOARD_RECOVERYIMAGE_PARTITION_SIZE
- $(hide) echo "recovery_size=$(BOARD_RECOVERYIMAGE_PARTITION_SIZE)" >> $(zip_root)/META/misc_info.txt
- endif
- ifdef BOARD_SYSTEMIMAGE_PARTITION_SIZE
- $(hide) echo "system_size=$(BOARD_SYSTEMIMAGE_PARTITION_SIZE)" >> $(zip_root)/META/misc_info.txt
- endif
- ifdef BOARD_USERDATAIMAGE_PARTITION_SIZE
- $(hide) echo "userdata_size=$(BOARD_USERDATAIMAGE_PARTITION_SIZE)" >> $(zip_root)/META/misc_info.txt
- endif
- $(hide) echo "tool_extensions=$(tool_extensions)" >> $(zip_root)/META/misc_info.txt
- ifdef mkyaffs2_extra_flags
- $(hide) echo "mkyaffs2_extra_flags=$(mkyaffs2_extra_flags)" >> $(zip_root)/META/misc_info.txt
- endif
- @# Zip everything up, preserving symlinks
- $(hide) (cd $(zip_root) && zip -qry ../$(notdir $@) .)
- @# Run fs_config on all the system files in the zip, and save the output
- $(hide) zipinfo -1 $@ | awk -F/ 'BEGIN { OFS="/" } /^SYSTEM\// {$$1 = "system"; print}' | $(HOST_OUT_EXECUTABLES)/fs_config > $(zip_root)/META/filesystem_config.txt
- $(hide) (cd $(zip_root) && zip -q ../$(notdir $@) META/filesystem_config.txt)
-
-
- target-files-package: $(BUILT_TARGET_FILES_PACKAGE)
-
-
- ifneq ($(TARGET_SIMULATOR),true)
- ifneq ($(TARGET_PRODUCT),sdk)
- ifneq ($(TARGET_DEVICE),generic)
- ifneq ($(TARGET_NO_KERNEL),true)
- ifneq ($(recovery_fstab),)
根據上面的Makefile能夠分析這個包的生成過程:
首先建立一個root_zip根目錄,並依次在此目錄下建立所須要的以下其餘目錄
①建立RECOVERY目錄,並填充該目錄的內容,包括kernel的鏡像和recovery根文件系統的鏡像。此目錄最終用於生成recovery.img。
②建立並填充BOOT目錄。包含kernel和cmdline以及pagesize大小等,該目錄最終用來生成boot.img。
③向SYSTEM目錄填充system image。
④向DATA填充data image。
⑤用於生成OTA package包所須要的額外的內容。主要包括一些bin命令。
⑥建立META目錄並向該目錄下添加一些文本文件,如apkcerts.txt(描述apk文件用到的認證證書),misc_info.txt(描述Flash內存的塊大小以及boot、recovery、system、userdata等分區的大小信息)。
⑦使用保留鏈接選項壓縮咱們在上面得到的root_zip目錄。
⑧使用fs_config(build/tools/fs_config)配置上面的zip包內全部的系統文件(system/下各目錄、文件)的權限屬主等信息。fs_config包含了一個頭文件#include「private/android_filesystem_config.h」。在這個頭文件中以硬編碼的方式設定了system目錄下各文件的權限、屬主。執行完配置後會將配置後的信息以文本方式輸出 到META/filesystem_config.txt中。並再一次zip壓縮成咱們最終須要的原始包。
第二步:上面的zip包只是一個編譯過程當中生成的原始包。這個原始zip包在實際的編譯過程當中有兩個做用,一是用來生成OTA update升級包,二是用來生成系統鏡像。在編譯過程當中若生成OTA update升級包時會調用(具體位置在Makefile的1037行到1058行)一個名爲ota_from_target_files的Python腳本,位置在/build/tools/releasetools/ota_from_target_files。這個腳本的做用是以第一步生成的zip原始包做爲輸入,最終生成可用的OTA升級zip包。
下面咱們分析使用這個腳本生成最終OTA升級包的過程。
㈠ 首先看一下這個腳本開始部分的幫助文檔。代碼以下:
下面簡單翻譯一下他們的使用方法以及選項的做用。
Usage: ota_from_target_files [flags] input_target_files output_ota_package
-b 過期的。
-k簽名所使用的密鑰
-i生成增量OTA包時使用此選項。後面咱們會用到這個選項來生成OTA增量包。
-w是否清除userdata分區
-n在升級時是否不檢查時間戳,缺省要檢查,即缺省狀況下只能基於舊版本升級。
-e是否有額外運行的腳本
-m執行過程當中生成腳本(updater-script)所須要的格式,目前有兩種即amend和edify。對應上兩種版本升級時會採用不一樣的解釋器。缺省會同時生成兩種格式的腳 本。
-p定義腳本用到的一些可執行文件的路徑。
-s定義額外運行腳本的路徑。
-x定義額外運行的腳本可能用的鍵值對。
-v執行過程當中打印出執行的命令。
-h命令幫助
㈡ 下面咱們分析ota_from_target_files這個python腳本是怎樣生成最終zip包的。先講這個腳本的代碼貼出來以下:
- import sys
-
- if sys.hexversion < 0x02040000:
- print >> sys.stderr, "Python 2.4 or newer is required."
- sys.exit(1)
-
- import copy
- import errno
- import os
- import re
- import sha
- import subprocess
- import tempfile
- import time
- import zipfile
-
- import common
- import edify_generator
-
- OPTIONS = common.OPTIONS
- OPTIONS.package_key = "build/target/product/security/testkey"
- OPTIONS.incremental_source = None
- OPTIONS.require_verbatim = set()
- OPTIONS.prohibit_verbatim = set(("system/build.prop",))
- OPTIONS.patch_threshold = 0.95
- OPTIONS.wipe_user_data = False
- OPTIONS.omit_prereq = False
- OPTIONS.extra_script = None
- OPTIONS.worker_threads = 3
-
- def MostPopularKey(d, default):
-
- x = [(v, k) for (k, v) in d.iteritems()]
- if not x: return default
- x.sort()
- return x[-1][1]
-
-
- def IsSymlink(info):
-
- return (info.external_attr >> 16) == 0120777
-
-
- class Item:
-
- ITEMS = {}
- def __init__(self, name, dir=False):
- self.name = name
- self.uid = None
- self.gid = None
- self.mode = None
- self.dir = dir
-
- if name:
- self.parent = Item.Get(os.path.dirname(name), dir=True)
- self.parent.children.append(self)
- else:
- self.parent = None
- if dir:
- self.children = []
-
- def Dump(self, indent=0):
- if self.uid is not None:
- print "%s%s %d %d %o" % (" "*indent, self.name, self.uid, self.gid, self.mode)
- else:
- print "%s%s %s %s %s" % (" "*indent, self.name, self.uid, self.gid, self.mode)
- if self.dir:
- print "%s%s" % (" "*indent, self.descendants)
- print "%s%s" % (" "*indent, self.best_subtree)
- for i in self.children:
- i.Dump(indent=indent+1)
-
- @classmethod
- def Get(cls, name, dir=False):
- if name not in cls.ITEMS:
- cls.ITEMS[name] = Item(name, dir=dir)
- return cls.ITEMS[name]
-
- @classmethod
- def GetMetadata(cls, input_zip):
-
- try:
-
-
- output = input_zip.read("META/filesystem_config.txt")
- except KeyError:
-
-
-
-
- p = common.Run(["fs_config"], stdin=subprocess.PIPE,
- stdout=subprocess.PIPE, stderr=subprocess.PIPE)
- suffix = { False: "", True: "/" }
- input = "".join(["%s%s\n" % (i.name, suffix[i.dir])
- for i in cls.ITEMS.itervalues() if i.name])
- output, error = p.communicate(input)
- assert not error
-
- for line in output.split("\n"):
- if not line: continue
- name, uid, gid, mode = line.split()
- i = cls.ITEMS.get(name, None)
- if i is not None:
- i.uid = int(uid)
- i.gid = int(gid)
- i.mode = int(mode, 8)
- if i.dir:
- i.children.sort(key=lambda i: i.name)
-
-
- i = cls.ITEMS.get("system/recovery-from-boot.p", None)
- if i: i.uid, i.gid, i.mode = 0, 0, 0644
- i = cls.ITEMS.get("system/etc/install-recovery.sh", None)
- if i: i.uid, i.gid, i.mode = 0, 0, 0544
-
- def CountChildMetadata(self):
-
-
- assert self.dir
- d = self.descendants = {(self.uid, self.gid, self.mode, None): 1}
- for i in self.children:
- if i.dir:
- for k, v in i.CountChildMetadata().iteritems():
- d[k] = d.get(k, 0) + v
- else:
- k = (i.uid, i.gid, None, i.mode)
- d[k] = d.get(k, 0) + 1
-
-
-
-
-
-
- ug = {}
- for (uid, gid, _, _), count in d.iteritems():
- ug[(uid, gid)] = ug.get((uid, gid), 0) + count
- ug = MostPopularKey(ug, (0, 0))
-
-
-
- best_dmode = (0, 0755)
- best_fmode = (0, 0644)
- for k, count in d.iteritems():
- if k[:2] != ug: continue
- if k[2] is not None and count >= best_dmode[0]: best_dmode = (count, k[2])
- if k[3] is not None and count >= best_fmode[0]: best_fmode = (count, k[3])
- self.best_subtree = ug + (best_dmode[1], best_fmode[1])
-
- return d
-
- def SetPermissions(self, script):
-
-
- self.CountChildMetadata()
-
- def recurse(item, current):
-
-
-
-
- if item.dir:
- if current != item.best_subtree:
- script.SetPermissionsRecursive("/"+item.name, *item.best_subtree)
- current = item.best_subtree
-
- if item.uid != current[0] or item.gid != current[1] or \
- item.mode != current[2]:
- script.SetPermissions("/"+item.name, item.uid, item.gid, item.mode)
-
- for i in item.children:
- recurse(i, current)
- else:
- if item.uid != current[0] or item.gid != current[1] or \
- item.mode != current[3]:
- script.SetPermissions("/"+item.name, item.uid, item.gid, item.mode)
-
- recurse(self, (-1, -1, -1, -1))
-
-
- def CopySystemFiles(input_zip, output_zip=None,
- substitute=None):
-
-
- symlinks = []
-
- for info in input_zip.infolist():
- if info.filename.startswith("SYSTEM/"):
- basefilename = info.filename[7:]
- if IsSymlink(info):
- symlinks.append((input_zip.read(info.filename),
- "/system/" + basefilename))
- else:
- info2 = copy.copy(info)
- fn = info2.filename = "system/" + basefilename
- if substitute and fn in substitute and substitute[fn] is None:
- continue
- if output_zip is not None:
- if substitute and fn in substitute:
- data = substitute[fn]
- else:
- data = input_zip.read(info.filename)
- output_zip.writestr(info2, data)
- if fn.endswith("/"):
- Item.Get(fn[:-1], dir=True)
- else:
- Item.Get(fn, dir=False)
-
- symlinks.sort()
- return symlinks
-
-
- def SignOutput(temp_zip_name, output_zip_name):
- key_passwords = common.GetKeyPasswords([OPTIONS.package_key])
- pw = key_passwords[OPTIONS.package_key]
-
- common.SignFile(temp_zip_name, output_zip_name, OPTIONS.package_key, pw,
- whole_file=True)
-
-
- def AppendAssertions(script, input_zip):
- device = GetBuildProp("ro.product.device", input_zip)
- script.AssertDevice(device)
-
-
- def MakeRecoveryPatch(output_zip, recovery_img, boot_img):
-
-
- d = common.Difference(recovery_img, boot_img)
- _, _, patch = d.ComputePatch()
- common.ZipWriteStr(output_zip, "recovery/recovery-from-boot.p", patch)
- Item.Get("system/recovery-from-boot.p", dir=False)
-
- boot_type, boot_device = common.GetTypeAndDevice("/boot", OPTIONS.info_dict)
- recovery_type, recovery_device = common.GetTypeAndDevice("/recovery", OPTIONS.info_dict)
-
-
-
-
- HEADER_SIZE = 2048
- header_sha1 = sha.sha(recovery_img.data[:HEADER_SIZE]).hexdigest()
- sh =
- 'boot_sha1': boot_img.sha1,
- 'header_size': HEADER_SIZE,
- 'header_sha1': header_sha1,
- 'recovery_size': recovery_img.size,
- 'recovery_sha1': recovery_img.sha1,
- 'boot_type': boot_type,
- 'boot_device': boot_device,
- 'recovery_type': recovery_type,
- 'recovery_device': recovery_device,
- }
- common.ZipWriteStr(output_zip, "recovery/etc/install-recovery.sh", sh)
- return Item.Get("system/etc/install-recovery.sh", dir=False)
-
-
- def WriteFullOTAPackage(input_zip, output_zip):
-
-
-
- script = edify_generator.EdifyGenerator(3, OPTIONS.info_dict)
-
- metadata = {"post-build": GetBuildProp("ro.build.fingerprint", input_zip),
- "pre-device": GetBuildProp("ro.product.device", input_zip),
- "post-timestamp": GetBuildProp("ro.build.date.utc", input_zip),
- }
-
- device_specific = common.DeviceSpecificParams(
- input_zip=input_zip,
- input_version=OPTIONS.info_dict["recovery_api_version"],
- output_zip=output_zip,
- script=script,
- input_tmp=OPTIONS.input_tmp,
- metadata=metadata,
- info_dict=OPTIONS.info_dict)
-
- if not OPTIONS.omit_prereq:
- ts = GetBuildProp("ro.build.date.utc", input_zip)
- script.AssertOlderBuild(ts)
-
- AppendAssertions(script, input_zip)
- device_specific.FullOTA_Assertions()
-
- script.ShowProgress(0.5, 0)
-
- if OPTIONS.wipe_user_data:
- script.FormatPartition("/data")
-
- script.FormatPartition("/system")
- script.Mount("/system")
- script.UnpackPackageDir("recovery", "/system")
- script.UnpackPackageDir("system", "/system")
-
- symlinks = CopySystemFiles(input_zip, output_zip)
- script.MakeSymlinks(symlinks)
-
- boot_img = common.File("boot.img", common.BuildBootableImage(
- os.path.join(OPTIONS.input_tmp, "BOOT")))
- recovery_img = common.File("recovery.img", common.BuildBootableImage(
- os.path.join(OPTIONS.input_tmp, "RECOVERY")))
- MakeRecoveryPatch(output_zip, recovery_img, boot_img)
-
- Item.GetMetadata(input_zip)
- Item.Get("system").SetPermissions(script)
-
- common.CheckSize(boot_img.data, "boot.img", OPTIONS.info_dict)
- common.ZipWriteStr(output_zip, "boot.img", boot_img.data)
- script.ShowProgress(0.2, 0)
-
- script.ShowProgress(0.2, 10)
- script.WriteRawImage("/boot", "boot.img")
-
- script.ShowProgress(0.1, 0)
- device_specific.FullOTA_InstallEnd()
-
- if OPTIONS.extra_script is not None:
- script.AppendExtra(OPTIONS.extra_script)
-
- script.UnmountAll()
- script.AddToZip(input_zip, output_zip)
- WriteMetadata(metadata, output_zip)
-
-
- def WriteMetadata(metadata, output_zip):
- common.ZipWriteStr(output_zip, "META-INF/com/android/metadata",
- "".join(["%s=%s\n" % kv
- for kv in sorted(metadata.iteritems())]))
-
-
-
-
- def LoadSystemFiles(z):
-
- out = {}
- for info in z.infolist():
- if info.filename.startswith("SYSTEM/") and not IsSymlink(info):
- fn = "system/" + info.filename[7:]
- data = z.read(info.filename)
- out[fn] = common.File(fn, data)
- return out
-
-
- def GetBuildProp(property, z):
-
- bp = z.read("SYSTEM/build.prop")
- if not property:
- return bp
- m = re.search(re.escape(property) + r"=(.*)\n", bp)
- if not m:
- raise common.ExternalError("couldn't find %s in build.prop" % (property,))
- return m.group(1).strip()
-
-
- def WriteIncrementalOTAPackage(target_zip, source_zip, output_zip):
- source_version = OPTIONS.source_info_dict["recovery_api_version"]
- target_version = OPTIONS.target_info_dict["recovery_api_version"]
-
- if source_version == 0:
- print ("WARNING: generating edify script for a source that "
- "can't install it.")
- script = edify_generator.EdifyGenerator(source_version, OPTIONS.info_dict)
-
- metadata = {"pre-device": GetBuildProp("ro.product.device", source_zip),
- "post-timestamp": GetBuildProp("ro.build.date.utc", target_zip),
- }
-
- device_specific = common.DeviceSpecificParams(
- source_zip=source_zip,
- source_version=source_version,
- target_zip=target_zip,
- target_version=target_version,
- output_zip=output_zip,
- script=script,
- metadata=metadata,
- info_dict=OPTIONS.info_dict)
-
- print "Loading target..."
- target_data = LoadSystemFiles(target_zip)
- print "Loading source..."
- source_data = LoadSystemFiles(source_zip)
-
- verbatim_targets = []
- patch_list = []
- diffs = []
- largest_source_size = 0
- for fn in sorted(target_data.keys()):
- tf = target_data[fn]
- assert fn == tf.name
- sf = source_data.get(fn, None)
-
- if sf is None or fn in OPTIONS.require_verbatim:
-
- if fn in OPTIONS.prohibit_verbatim:
- raise common.ExternalError("\"%s\" must be sent verbatim" % (fn,))
- print "send", fn, "verbatim"
- tf.AddToZip(output_zip)
- verbatim_targets.append((fn, tf.size))
- elif tf.sha1 != sf.sha1:
-
- diffs.append(common.Difference(tf, sf))
- else:
-
- pass
-
- common.ComputeDifferences(diffs)
-
- for diff in diffs:
- tf, sf, d = diff.GetPatch()
- if d is None or len(d) > tf.size * OPTIONS.patch_threshold:
-
- tf.AddToZip(output_zip)
- verbatim_targets.append((tf.name, tf.size))
- else:
- common.ZipWriteStr(output_zip, "patch/" + tf.name + ".p", d)
- patch_list.append((tf.name, tf, sf, tf.size, sha.sha(d).hexdigest()))
- largest_source_size = max(largest_source_size, sf.size)
-
- source_fp = GetBuildProp("ro.build.fingerprint", source_zip)
- target_fp = GetBuildProp("ro.build.fingerprint", target_zip)
- metadata["pre-build"] = source_fp
- metadata["post-build"] = target_fp
-
- script.Mount("/system")
- script.AssertSomeFingerprint(source_fp, target_fp)
-
- source_boot = common.File("/tmp/boot.img",
- common.BuildBootableImage(
- os.path.join(OPTIONS.source_tmp, "BOOT")))
- target_boot = common.File("/tmp/boot.img",
- common.BuildBootableImage(
- os.path.join(OPTIONS.target_tmp, "BOOT")))
- updating_boot = (source_boot.data != target_boot.data)
-
- source_recovery = common.File("system/recovery.img",
- common.BuildBootableImage(
- os.path.join(OPTIONS.source_tmp, "RECOVERY")))
- target_recovery = common.File("system/recovery.img",
- common.BuildBootableImage(
- os.path.join(OPTIONS.target_tmp, "RECOVERY")))
- updating_recovery = (source_recovery.data != target_recovery.data)
-
-
-
-
-
-
-
- AppendAssertions(script, target_zip)
- device_specific.IncrementalOTA_Assertions()
-
- script.Print("Verifying current system...")
-
- script.ShowProgress(0.1, 0)
- total_verify_size = float(sum([i[2].size for i in patch_list]) + 1)
- if updating_boot:
- total_verify_size += source_boot.size
- so_far = 0
-
- for fn, tf, sf, size, patch_sha in patch_list:
- script.PatchCheck("/"+fn, tf.sha1, sf.sha1)
- so_far += sf.size
- script.SetProgress(so_far / total_verify_size)
-
- if updating_boot:
- d = common.Difference(target_boot, source_boot)
- _, _, d = d.ComputePatch()
- print "boot target: %d source: %d diff: %d" % (
- target_boot.size, source_boot.size, len(d))
-
- common.ZipWriteStr(output_zip, "patch/boot.img.p", d)
-
- boot_type, boot_device = common.GetTypeAndDevice("/boot", OPTIONS.info_dict)
-
- script.PatchCheck("%s:%s:%d:%s:%d:%s" %
- (boot_type, boot_device,
- source_boot.size, source_boot.sha1,
- target_boot.size, target_boot.sha1))
- so_far += source_boot.size
- script.SetProgress(so_far / total_verify_size)
-
- if patch_list or updating_recovery or updating_boot:
- script.CacheFreeSpaceCheck(largest_source_size)
-
- device_specific.IncrementalOTA_VerifyEnd()
-
- script.Comment("---- start making changes here ----")
-
- if OPTIONS.wipe_user_data:
- script.Print("Erasing user data...")
- script.FormatPartition("/data")
-
- script.Print("Removing unneeded files...")
- script.DeleteFiles(["/"+i[0] for i in verbatim_targets] +
- ["/"+i for i in sorted(source_data)
- if i not in target_data] +
- ["/system/recovery.img"])
-
- script.ShowProgress(0.8, 0)
- total_patch_size = float(sum([i[1].size for i in patch_list]) + 1)
- if updating_boot:
- total_patch_size += target_boot.size
- so_far = 0
-
- script.Print("Patching system files...")
- for fn, tf, sf, size, _ in patch_list:
- script.ApplyPatch("/"+fn, "-", tf.size, tf.sha1, sf.sha1, "patch/"+fn+".p")
- so_far += tf.size
- script.SetProgress(so_far / total_patch_size)
-
- if updating_boot:
-
-
-
- script.Print("Patching boot image...")
- script.ApplyPatch("%s:%s:%d:%s:%d:%s"
- % (boot_type, boot_device,
- source_boot.size, source_boot.sha1,
- target_boot.size, target_boot.sha1),
- "-",
- target_boot.size, target_boot.sha1,
- source_boot.sha1, "patch/boot.img.p")
- so_far += target_boot.size
- script.SetProgress(so_far / total_patch_size)
- print "boot image changed; including."
- else:
- print "boot image unchanged; skipping."
-
- if updating_recovery:
-
-
-
-
-
-
-
-
-
-
-
- MakeRecoveryPatch(output_zip, target_recovery, target_boot)
- script.DeleteFiles(["/system/recovery-from-boot.p",
- "/system/etc/install-recovery.sh"])
- print "recovery image changed; including as patch from boot."
- else:
- print "recovery image unchanged; skipping."
-
- script.ShowProgress(0.1, 10)
-
- target_symlinks = CopySystemFiles(target_zip, None)
-
- target_symlinks_d = dict([(i[1], i[0]) for i in target_symlinks])
- temp_script = script.MakeTemporary()
- Item.GetMetadata(target_zip)
- Item.Get("system").SetPermissions(temp_script)
-
-
-
- source_symlinks = CopySystemFiles(source_zip, None)
- source_symlinks_d = dict([(i[1], i[0]) for i in source_symlinks])
-
-
-
-
- to_delete = []
- for dest, link in source_symlinks:
- if link not in target_symlinks_d:
- to_delete.append(link)
- script.DeleteFiles(to_delete)
-
- if verbatim_targets:
- script.Print("Unpacking new files...")
- script.UnpackPackageDir("system", "/system")
-
- if updating_recovery:
- script.Print("Unpacking new recovery...")
- script.UnpackPackageDir("recovery", "/system")
-
- script.Print("Symlinks and permissions...")
-
-
-
-
- to_create = []
- for dest, link in target_symlinks:
- if link in source_symlinks_d:
- if dest != source_symlinks_d[link]:
- to_create.append((dest, link))
- else:
- to_create.append((dest, link))
- script.DeleteFiles([i[1] for i in to_create])
- script.MakeSymlinks(to_create)
-
-
-
- script.AppendScript(temp_script)
-
-
- device_specific.IncrementalOTA_InstallEnd()
-
- if OPTIONS.extra_script is not None:
- scirpt.AppendExtra(OPTIONS.extra_script)
-
- script.AddToZip(target_zip, output_zip)
- WriteMetadata(metadata, output_zip)
-
-
- def main(argv):
-
- def option_handler(o, a):
- if o in ("-b", "--board_config"):
- pass
- elif o in ("-k", "--package_key"):
- OPTIONS.package_key = a
- elif o in ("-i", "--incremental_from"):
- OPTIONS.incremental_source = a
- elif o in ("-w", "--wipe_user_data"):
- OPTIONS.wipe_user_data = True
- elif o in ("-n", "--no_prereq"):
- OPTIONS.omit_prereq = True
- elif o in ("-e", "--extra_script"):
- OPTIONS.extra_script = a
- elif o in ("--worker_threads"):
- OPTIONS.worker_threads = int(a)
- else:
- return False
- return True
-
- args = common.ParseOptions(argv, __doc__,
- extra_opts="b:k:i:d:wne:",
- extra_long_opts=["board_config=",
- "package_key=",
- "incremental_from=",
- "wipe_user_data",
- "no_prereq",
- "extra_script=",
- "worker_threads="],
- extra_option_handler=option_handler)
-
- if len(args) != 2:
- common.Usage(__doc__)
- sys.exit(1)
-
- if OPTIONS.extra_script is not None:
- OPTIONS.extra_script = open(OPTIONS.extra_script).read()
-
- print "unzipping target target-files..."
- OPTIONS.input_tmp = common.UnzipTemp(args[0])
-
- OPTIONS.target_tmp = OPTIONS.input_tmp
- input_zip = zipfile.ZipFile(args[0], "r")
- OPTIONS.info_dict = common.LoadInfoDict(input_zip)
- if OPTIONS.verbose:
- print "--- target info ---"
- common.DumpInfoDict(OPTIONS.info_dict)
-
- if OPTIONS.device_specific is None:
- OPTIONS.device_specific = OPTIONS.info_dict.get("tool_extensions", None)
- if OPTIONS.device_specific is not None:
- OPTIONS.device_specific = os.path.normpath(OPTIONS.device_specific)
- print "using device-specific extensions in", OPTIONS.device_specific
-
- if OPTIONS.package_key:
- temp_zip_file = tempfile.NamedTemporaryFile()
- output_zip = zipfile.ZipFile(temp_zip_file, "w",
- compression=zipfile.ZIP_DEFLATED)
- else:
- output_zip = zipfile.ZipFile(args[1], "w",
- compression=zipfile.ZIP_DEFLATED)
-
- if OPTIONS.incremental_source is None:
- WriteFullOTAPackage(input_zip, output_zip)
- else:
- print "unzipping source target-files..."
- OPTIONS.source_tmp = common.UnzipTemp(OPTIONS.incremental_source)
- source_zip = zipfile.ZipFile(OPTIONS.incremental_source, "r")
- OPTIONS.target_info_dict = OPTIONS.info_dict
- OPTIONS.source_info_dict = common.LoadInfoDict(source_zip)
- if OPTIONS.verbose:
- print "--- source info ---"
- common.DumpInfoDict(OPTIONS.source_info_dict)
- WriteIncrementalOTAPackage(input_zip, source_zip, output_zip)
-
- output_zip.close()
- if OPTIONS.package_key:
- SignOutput(temp_zip_file.name, args[1])
- temp_zip_file.close()
-
- common.Cleanup()
-
- print "done."
-
-
- if __name__ == '__main__':
- try:
- common.CloseInheritedPipes()
- main(sys.argv[1:])
- except common.ExternalError, e:
- print
- print " ERROR: %s" % (e,)
- print
- sys.exit(1)
主函數main是python的入口函數,咱們從main函數開始看,大概看一下main函數(腳本最後)裏的流程就能知道腳本的執行過程了。
① 在main函數的開頭,首先將用戶設定的option選項存入OPTIONS變量中,它是一個python中的類。緊接着判斷有沒有額外的腳本,若是有就讀入到OPTIONS變量中。
② 解壓縮輸入的zip包,即咱們在上文生成的原始zip包。而後判斷是否用到device-specific extensions(設備擴展)若是用到,隨即讀入到OPTIONS變量中。
③ 判斷是否簽名,而後判斷是否有新內容的增量源,有的話就解壓該增量源包放入一個臨時變量中(source_zip)。自此,全部的準備工做已完畢,隨即會調用該 腳本中最主要的函數WriteFullOTAPackage(input_zip,output_zip)
④ WriteFullOTAPackage函數的處理過程是先得到腳本的生成器。默認格式是edify。而後得到metadata元數據,此數據來至於Android的一些環境變量。而後得到設備配置參數好比api函數的版本。而後判斷是否忽略時間戳。
⑤ WriteFullOTAPackage函數作完準備工做後就開始生成升級用的腳本文件(updater-script)了。生成腳本文件後將上一步得到的metadata元數據寫入到輸出包out_zip。
⑥至此一個完整的update.zip升級包就生成了。生成位置在:out/target/product/tcc8800/full_tcc8800_evm-ota-eng.mumu.20120315.155326.zip。將升級包拷貝到SD卡中就能夠用來升級了。
4、
Android OTA增量包update.zip的生成
在上面的過程當中生成的update.zip升級包是所有系統的升級包。大小有80M多。這對手機用戶來講,用來升級的流量是很大的。並且在實際升級中,咱們只但願可以升級咱們改變的那部份內容。這就須要使用增量包來升級。生成增量包的過程也須要上文中提到的ota_from_target_files.py的參與。
下面是製做update.zip增量包的過程。
① 在源碼根目錄下依次執行下列命令
$ . build/envsetup.sh
$ lunch 選擇17
$ make
$ make otapackage
執行上面的命令後會在out/target/product/tcc8800/下生成咱們第一個系統升級包。咱們先將其命名爲A.zip
② 在源碼中修改咱們須要改變的部分,好比修改內核配置,增長新的驅動等等。修改後再一次執行上面的命令。就會生成第二個咱們修改後生成的update.zip升級包。將 其命名爲B.zip。
③ 在上文中咱們看了ota_from_target_files.py腳本的使用幫助,其中選項-i就是用來生成差分增量包的。使用方法是以上面的A.zip 和B.zip包做爲輸入,以update.zip包做 爲輸出。生成的update.zip就是咱們最後須要的增量包。
具體使用方式是:將上述兩個包拷貝到源碼根目錄下,而後執行下面的命令。
$ ./build/tools/releasetools/ota_from_target_files -i A.zip B.zip update.zip。
在執行上述命令時會出現未找到recovery_api_version的錯誤。緣由是在執行上面的腳本時若是使用選項i則會調用WriteIncrementalOTAPackage會從A包和B包中的META目錄下搜索misc_info.txt來讀取recovery_api_version的值。可是在執行make otapackage命令時生成的update.zip包中沒有這個目錄更沒有這個文檔。
此時咱們就須要使用執行make otapackage生成的原始的zip包。這個包的位置在out/target/product/tcc8800/obj/PACKAGING/target_files_intermediates/目錄下,它是在用命令make otapackage以後的中間生產物,是最原始的升級包。咱們將兩次編譯的生成的包分別重命名爲A.zip和B.zip,並拷貝到SD卡根目錄下重複執行上面的命令:
$ ./build/tools/releasetools/ota_form_target_files -i A.zip B.zip update.zip。
在上述命令即將執行完畢時,在device/telechips/common/releasetools.py會調用IncrementalOTA_InstallEnd,在這個函數中讀取包中的RADIO/bootloader.img。
而包中是沒有這個目錄和bootloader.img的。因此執行失敗,未能生成對應的update.zip。可能與咱們未修改bootloader(升級firmware)有關。此問題在下一篇博客已經解決。
在下一篇中講解制做增量包失敗的緣由,以及解決方案。