From 80f63ee9d1e5e6e3666c5dbfe84140d3f1df4ab6 Mon Sep 17 00:00:00 2001
From: Luca Stefani <luca.stefani.ge1@gmail.com>
Date: Thu, 11 Jun 2020 13:03:18 +0200
Subject: [PATCH] Add build support for XZ ramdisks

Co-authored-by: Arne Coucheron <arco68@gmail.com>
Change-Id: I61530b6da06e0038970551aa4d12bce02007ae3c
---
 core/Makefile                | 22 ++++++++++++++++++++--
 tools/releasetools/common.py | 16 ++++++++++++++--
 2 files changed, 34 insertions(+), 4 deletions(-)

diff --git a/core/Makefile b/core/Makefile
index 7122a7e626..2b0e65d4f0 100644
--- a/core/Makefile
+++ b/core/Makefile
@@ -1267,6 +1267,21 @@ boototapackage_16k: $(BUILT_BOOT_OTA_PACKAGE_16K)
 
 endif
 
+ifeq ($(BOARD_RAMDISK_USE_LZ4),true)
+# -l enables the legacy format used by the Linux kernel
+COMPRESSION_COMMAND_DEPS := $(LZ4)
+COMPRESSION_COMMAND := $(LZ4) -l -12 --favor-decSpeed
+RAMDISK_EXT := .lz4
+else ifeq ($(BOARD_RAMDISK_USE_XZ),true)
+COMPRESSION_COMMAND_DEPS := $(XZ)
+COMPRESSION_COMMAND := $(XZ) -f -c --check=crc32 --lzma2=dict=32MiB
+RAMDISK_EXT := .xz
+else
+COMPRESSION_COMMAND_DEPS := $(GZIP)
+COMPRESSION_COMMAND := $(GZIP)
+RAMDISK_EXT := .gz
+endif
+
 # The value of RAMDISK_NODE_LIST is defined in system/core/rootdir/Android.bp.
 # This file contains /dev nodes description added to the generic ramdisk
 
@@ -2658,7 +2673,7 @@ endif
 
 ifeq (,$(filter true, $(BOARD_USES_FULL_RECOVERY_IMAGE) $(BOARD_USES_RECOVERY_AS_BOOT) \
   $(BOARD_INCLUDE_RECOVERY_DTBO) $(BOARD_INCLUDE_RECOVERY_ACPIO) \
-  $(BOARD_MOVE_RECOVERY_RESOURCES_TO_VENDOR_BOOT) $(BOARD_RAMDISK_USE_LZ4)))
+  $(BOARD_MOVE_RECOVERY_RESOURCES_TO_VENDOR_BOOT) $(BOARD_RAMDISK_USE_LZ4) $(BOARD_RAMDISK_USE_XZ)))
 # Named '.dat' so we don't attempt to use imgdiff for patching it.
 RECOVERY_RESOURCE_ZIP := $(TARGET_OUT_VENDOR)/etc/recovery-resource.dat
 ALL_DEFAULT_INSTALLED_MODULES += $(RECOVERY_RESOURCE_ZIP)
@@ -3615,7 +3630,7 @@ ifneq ($(INSTALLED_BOOTIMAGE_TARGET),)
 ifneq ($(INSTALLED_RECOVERYIMAGE_TARGET),)
 ifneq ($(BOARD_USES_FULL_RECOVERY_IMAGE),true)
 ifneq (,$(filter true,$(BOARD_INCLUDE_RECOVERY_DTBO) $(BOARD_INCLUDE_RECOVERY_ACPIO) \
-      $(BOARD_RAMDISK_USE_LZ4)))
+      $(BOARD_RAMDISK_USE_LZ4) $(BOARD_RAMDISK_USE_XZ)))
 diff_tool := $(HOST_OUT_EXECUTABLES)/bsdiff
 else
 diff_tool := $(HOST_OUT_EXECUTABLES)/imgdiff
@@ -5902,6 +5917,9 @@ endif
 ifeq ($(BOARD_RAMDISK_USE_LZ4),true)
 	echo "lz4_ramdisks=true" >> $@
 endif
+ifeq ($(BOARD_RAMDISK_USE_XZ),true)
+	echo "xz_ramdisks=true" >> $@
+endif
 ifneq ($(INSTALLED_VENDOR_BOOTIMAGE_TARGET),)
 	echo "vendor_boot=true" >> $@
 	echo "vendor_boot_size=$(BOARD_VENDOR_BOOTIMAGE_PARTITION_SIZE)" >> $@
diff --git a/tools/releasetools/common.py b/tools/releasetools/common.py
index dd24288f25..a5f88f05c2 100644
--- a/tools/releasetools/common.py
+++ b/tools/releasetools/common.py
@@ -832,11 +832,14 @@ def ExtractFromInputFile(input_file, fn):
 class RamdiskFormat(object):
   LZ4 = 1
   GZ = 2
+  XZ = 3
 
 
 def GetRamdiskFormat(info_dict):
   if info_dict.get('lz4_ramdisks') == 'true':
     ramdisk_format = RamdiskFormat.LZ4
+  elif info_dict.get('xz_ramdisks') == 'true':
+    ramdisk_format = RamdiskFormat.XZ
   else:
     ramdisk_format = RamdiskFormat.GZ
   return ramdisk_format
@@ -1694,10 +1697,13 @@ def _MakeRamdisk(sourcedir, fs_config_file=None,
   if ramdisk_format == RamdiskFormat.LZ4:
     p2 = Run(["lz4", "-l", "-12", "--favor-decSpeed"], stdin=p1.stdout,
              stdout=ramdisk_img.file.fileno())
+  elif ramdisk_format == RamdiskFormat.XZ:
+    p2 = Run(["xz", "-f", "-c", "--check=crc32", "--lzma2=dict=32MiB"], stdin=p1.stdout,
+             stdout=ramdisk_img.file.fileno())
   elif ramdisk_format == RamdiskFormat.GZ:
     p2 = Run(["gzip"], stdin=p1.stdout, stdout=ramdisk_img.file.fileno())
   else:
-    raise ValueError("Only support lz4 or gzip ramdisk format.")
+    raise ValueError("Only support lz4, xz, or gzip ramdisk format.")
 
   p2.wait()
   p1.wait()
@@ -4164,8 +4170,14 @@ def GetBootImageBuildProp(boot_img, ramdisk_format=RamdiskFormat.LZ4):
           p2 = Run(['gzip', '-d'], stdin=input_stream.fileno(),
                    stdout=output_stream.fileno())
           p2.wait()
+    elif ramdisk_format == RamdiskFormat.XZ:
+      with open(ramdisk, 'rb') as input_stream:
+        with open(uncompressed_ramdisk, 'wb') as output_stream:
+          p2 = Run(['xz', '-d'], stdin=input_stream.fileno(),
+                   stdout=output_stream.fileno())
+          p2.wait()
     else:
-      logger.error('Only support lz4 or gzip ramdisk format.')
+      logger.error('Only support lz4, xz, or gzip ramdisk format.')
       return None
 
     abs_uncompressed_ramdisk = os.path.abspath(uncompressed_ramdisk)