From e62522c5a166c9466d1e90b015d57240743e9e60 Mon Sep 17 00:00:00 2001
From: Marcelo Politzer <251334+mpolitzer@users.noreply.github.com>
Date: Thu, 24 Aug 2023 15:51:38 -0300
Subject: [PATCH] feat: forward application exit status

---
 Dockerfile                |  2 +
 Makefile                  |  2 +-
 linux/xhalt/.gitignore    |  2 +
 linux/xhalt/Makefile      | 77 +++++++++++++++++++++++++++++++++++++++
 linux/xhalt/README.md     | 41 +++++++++++++++++++++
 linux/xhalt/xhalt.c       |  9 +++++
 skel/opt/cartesi/bin/init |  4 +-
 7 files changed, 135 insertions(+), 2 deletions(-)
 create mode 100644 linux/xhalt/.gitignore
 create mode 100644 linux/xhalt/Makefile
 create mode 100644 linux/xhalt/README.md
 create mode 100644 linux/xhalt/xhalt.c

diff --git a/Dockerfile b/Dockerfile
index 477e7569..0f833da3 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -62,6 +62,7 @@ COPY linux/ ${BUILD_BASE}tools/linux/
 
 # build C/C++ tools
 # ------------------------------------------------------------------------------
+RUN make -C ${BUILD_BASE}tools/linux/xhalt/ CROSS_COMPILE="" xhalt.toolchain
 RUN make -C ${BUILD_BASE}tools/linux/htif/ CROSS_COMPILE="" yield.toolchain
 RUN make -C ${BUILD_BASE}tools/linux/rollup/ioctl-echo-loop/ CROSS_COMPILE="" ioctl-echo-loop.toolchain
 RUN make -C ${BUILD_BASE}tools/linux/rollup/rollup/ CROSS_COMPILE="" rollup.toolchain
@@ -87,6 +88,7 @@ ARG MACHINE_EMULATOR_TOOLS_TAR_GZ=machine-emulator-tools.tar.gz
 COPY skel/ ${STAGING_BASE}
 RUN mkdir -p ${STAGING_BIN} && \
     cp ${BUILD_BASE}twuewand/rndaddentropy/rndaddentropy ${STAGING_BIN} && \
+    cp ${BUILD_BASE}tools/linux/xhalt/xhalt ${STAGING_BIN} && \
     cp ${BUILD_BASE}tools/linux/htif/yield ${STAGING_BIN} && \
     cp ${BUILD_BASE}tools/linux/rollup/ioctl-echo-loop/ioctl-echo-loop ${STAGING_BIN} && \
     cp ${BUILD_BASE}tools/linux/rollup/rollup/rollup ${STAGING_BIN} && \
diff --git a/Makefile b/Makefile
index 87a6ec2d..61465640 100644
--- a/Makefile
+++ b/Makefile
@@ -38,7 +38,7 @@ SHASUMFILES := $(LINUX_SOURCES_FILEPATH) $(RNDADDENTROPY_FILEPATH)
 all: build copy
 
 build: Dockerfile checksum
-	docker buildx build --platform=linux/riscv64 \
+	docker buildx build --platform=linux/riscv64 --load \
 		--build-arg MACHINE_EMULATOR_TOOLS_TAR_GZ=$(MACHINE_EMULATOR_TOOLS_TAR_GZ) \
 		--build-arg MACHINE_EMULATOR_TOOLS_DEB=$(MACHINE_EMULATOR_TOOLS_DEB) \
 		--build-arg LINUX_SOURCES_VERSION=$(LINUX_SOURCES_VERSION) \
diff --git a/linux/xhalt/.gitignore b/linux/xhalt/.gitignore
new file mode 100644
index 00000000..99593ec3
--- /dev/null
+++ b/linux/xhalt/.gitignore
@@ -0,0 +1,2 @@
+extra/halt
+halt
diff --git a/linux/xhalt/Makefile b/linux/xhalt/Makefile
new file mode 100644
index 00000000..76481a66
--- /dev/null
+++ b/linux/xhalt/Makefile
@@ -0,0 +1,77 @@
+# Copyright Cartesi and individual authors (see AUTHORS)
+# SPDX-License-Identifier: Apache-2.0
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+UNAME:=$(shell uname)
+
+TOOLCHAIN_IMAGE ?= cartesi/toolchain
+TOOLCHAIN_TAG ?= 0.15.0
+RISCV_ARCH ?= rv64gc
+RISCV_ABI ?= lp64d
+
+CROSS_COMPILE = riscv64-cartesi-linux-gnu-
+RVCC  = $(CROSS_COMPILE)gcc
+RVCXX = $(CROSS_COMPILE)g++
+RVCOPY = $(CROSS_COMPILE)objcopy
+RVDUMP = $(CROSS_COMPILE)objdump
+STRIP = $(CROSS_COMPILE)strip
+RISCV_CFLAGS :=-march=$(RISCV_ARCH) -mabi=$(RISCV_ABI)
+
+CONTAINER_MAKE := /usr/bin/make
+CONTAINER_BASE := /opt/cartesi/tools
+KERNEL_HEADERS_PATH := /opt/riscv/usr/include
+
+all: xhalt
+
+xhalt: xhalt.c
+	$(MAKE) toolchain-exec CONTAINER_COMMAND="$(CONTAINER_MAKE) $@.toolchain"
+
+extra.ext2: xhalt
+	$(MAKE) toolchain-exec CONTAINER_COMMAND="$(CONTAINER_MAKE) $@.toolchain"
+
+xhalt.toolchain:
+	$(RVCC) -O2 -o xhalt xhalt.c
+	$(STRIP) xhalt
+
+extra.ext2.toolchain:
+	mkdir -m 0755 ./extra
+	cp ./xhalt ./extra/xhalt
+	genext2fs -i 512 -b 8192 -d extra $(basename $@)
+	rm -rf ./extra
+
+toolchain-exec:
+	@docker run --hostname $@ --rm \
+		-e USER=$$(id -u -n) \
+		-e GROUP=$$(id -g -n) \
+		-e UID=$$(id -u) \
+		-e GID=$$(id -g) \
+		-v `pwd`:$(CONTAINER_BASE) \
+		-w $(CONTAINER_BASE) \
+		$(TOOLCHAIN_IMAGE):$(TOOLCHAIN_TAG) $(CONTAINER_COMMAND)
+
+toolchain-env:
+	@docker run --hostname toolchain-env -it --rm \
+		-e USER=$$(id -u -n) \
+		-e GROUP=$$(id -g -n) \
+		-e UID=$$(id -u) \
+		-e GID=$$(id -g) \
+		-v `pwd`:$(CONTAINER_BASE) \
+		-w $(CONTAINER_BASE) \
+		$(TOOLCHAIN_IMAGE):$(TOOLCHAIN_TAG)
+
+clean:
+	\rm -rf xhalt extra.ext2 extra
+
+.PHONY: toolchain-exec toolchain-env
diff --git a/linux/xhalt/README.md b/linux/xhalt/README.md
new file mode 100644
index 00000000..16a33a71
--- /dev/null
+++ b/linux/xhalt/README.md
@@ -0,0 +1,41 @@
+## HTIF xhalt tool
+
+### Requirements
+
+- Docker >= 18.x
+- GNU Make >= 3.81
+
+### Building
+
+```bash
+$ cd linux/htif
+$ make
+```
+
+#### Makefile targets
+
+The following options are available as `make` targets:
+
+- **all**: builds the RISC-V xhalt executable
+- **extra.ext2**: builds the extra.ext2 filesystem image with the xhalt tool inside
+- **toolchain-env**: runs the toolchain image with current user UID and GID
+- **clean**: clean generated artifacts
+
+#### Makefile container options
+
+You can pass the following variables to the make target if you wish to use different docker image tags.
+
+- TOOLCHAIN\_IMAGE: toolchain image name
+- TOOLCHAIN\_TAG: toolchain image tag
+
+```
+$ make TOOLCHAIN_TAG=mytag
+```
+
+It's useful when you want to use prebuilt images like `cartesi/toolchain:latest`
+
+#### Usage
+
+The purpose of the xhalt tool please see the emulator documentation.
+
+The purpose of the `extra.ext2` image is to help the development creating a filesystem that contains the xhalt tool so it can be used with the emulator. For instructions on how to do that, please see the emulator documentation.
diff --git a/linux/xhalt/xhalt.c b/linux/xhalt/xhalt.c
new file mode 100644
index 00000000..4a01e3d3
--- /dev/null
+++ b/linux/xhalt/xhalt.c
@@ -0,0 +1,9 @@
+#include <stdio.h>
+#include <unistd.h>
+#include <syscall.h>
+#include <linux/reboot.h>
+
+int main(int argc, char *argv[]) {
+	const char *halt = argc > 1? argv[1] : "0";
+	syscall(SYS_reboot, LINUX_REBOOT_MAGIC1, LINUX_REBOOT_MAGIC2, LINUX_REBOOT_CMD_RESTART2, halt);
+}
diff --git a/skel/opt/cartesi/bin/init b/skel/opt/cartesi/bin/init
index d462a692..7995d1ee 100755
--- a/skel/opt/cartesi/bin/init
+++ b/skel/opt/cartesi/bin/init
@@ -74,10 +74,12 @@ if [ -n "$*" ]; then
         busybox setsid \
         busybox cttyhack \
         busybox su -p $USER -c "$*"
+    RC=$?
 else
     echo "Nothing to do."
+    RC=0
 fi
 
 busybox mount -o ro,remount /
 busybox umount -af
-busybox poweroff -f
+[ $RC == 0 ] && busybox poweroff -f || xhalt "$RC"