Allow user to download and extract alpinelinux rootfs in Makefile

Makefile

@@ -12,6 +12,10 @@ rust_bins := $(patsubst $(rust_src_dir)/%.rs, $(rust_bin_path)/%, $(wildcard $(r
 ucore_bin_path := ucore/build/$(arch)
 biscuit_bin_path := biscuit/build/$(arch)
 busybox := $(out_dir)/busybox
+alpine_version_major := 3.9
+alpine_version_full := 3.9.2
+alpine_file := alpine-minirootfs-3.9.2-$(arch).tar.gz
+alpine := alpine/$(alpine_file)
 
 rust_build_args := --target targets/$(arch)-rcore.json
 cmake_build_args := -DARCH=$(arch)
@@ -22,7 +26,7 @@ cmake_build_args += -DCMAKE_BUILD_TYPE=Release
 endif
 
 
-.PHONY: all clean build rust ucore biscuit bin busybox nginx redis
+.PHONY: all clean build rust ucore biscuit bin busybox nginx redis alpine
 
 all: build
 
@@ -92,6 +96,15 @@ ifneq ($(shell uname), Darwin)
 endif
 endif
 
+$(alpine):
+	wget "http://dl-cdn.alpinelinux.org/alpine/v3.9/releases/$(arch)/$(alpine_file)" -O $(alpine)
+
+alpine: $(alpine)
+ifeq ($(arch), $(filter $(arch), x86_64 aarch64))
+	@mkdir -p $(out_dir)
+	@cd $(out_dir) && tar xvf ../../$(alpine)
+endif
+
 build: rust ucore biscuit $(busybox) nginx redis
 
 sfsimg: $(out_qcow2)

README.md

@@ -10,28 +10,30 @@ Now it has 4 parts:
 * `ucore`: C-lang, from the original [ucore_os_lab](https://github.com/chyyuu/ucore_os_plus)
 * `biscuit`: C/C++, from [Biscuit](https://github.com/mit-pdos/biscuit), based on a `musl` instead of original `litc`.
 * `rust`: Simple no_std Rust programs.
-* `nginx`, `redis`: Real world applications.
+* `nginx`, `redis`, `busybox`, `alpine`: Real world applications.
 
 ## Build
 
 To build biscuit programs, install musl toolchain first:
 
 ```bash
-# for ARCH linux
-$ sudo pacman -Syu musl # archlinux
-# for macOS
-$ brew install FileSottile/musl-cross/musl-cross 
-# for ubuntu 16.04, we should build gcc-musl for newest musl-1.1.21
-# please see build-gcc-musl.md
-# for riscv musl toolchain, please install [musl-riscv-toolchain](https://github.com/jiegec/musl-riscv-toolchain)
+# 1. to download prebuilt binaries in Linux, visit [musl.cc](https://musl.cc)
+# 2. to build musl toolchains from source:
+# 2.1 for macOS musl toolchain for x86_64(,aarch64)
+$ brew install FileSottile/musl-cross/musl-cross {--with-aarch64}
+# 2.2 for ubuntu 16.04, we should build gcc-musl for newest musl-1.1.21, please see build-gcc-musl.md for instructions
+# 2.3 for riscv musl toolchain, please install [musl-riscv-toolchain](https://github.com/jiegec/musl-riscv-toolchain)
 ```
 
+Then, build userspace programs for rCore:
+
 ```bash
 $ make {ucore,biscuit,rust,nginx,redis,all} arch={x86_64,aarch64,riscv32,riscv64}
+$ make alpine arch={x86_64,aarch64} # if you want to use alpine rootfs
 $ make sfsimg arch={x86_64,aarch64,riscv32,riscv64}
 ```
 
-Output to `build/$(arch)`
+A rootfs is created at `build/$(arch)` and converted to `qcow2`.
 
 ## Support matrix
 
@@ -43,18 +45,21 @@ Output to `build/$(arch)`
 | nginx (linux only) | ✅      | ✅       | ❌       | ✅       |
 | redis (linux only) | ✅      | ✅       | ✅       | ❌       |
 | busybox            | ✅      | ✅       | ❌       | ✅       |
+| alpine rootfs      | ✅      | ✅       | ❌       | ❌       |
 
 
 
 ## How to use Redis
 
-After running commands above, you should be able to run redis-server in rCore. Then, start `redis-server` in rCore:
+If redis is dynamically linked to musl (default if you use commands above), you might need to copy `ld-musl-$(arch).so.1` to rootfs `/lib` . Alpine rootfs includes one as well.
+
+After building redis, you should be able to run redis-server in rCore. Then, start `redis-server` in rCore:
 
 ```bash
 /> redis-server redis.conf
 ```
 
-Then you should be able to connect to it using `redis-cli`:
+Then you should be able to connect to it using `redis-cli` over the network:
 
 ```bash
 $ redis-cli -h 10.0.0.2 set abc def

alpine/.gitignore

@@ -0,0 +1 @@
+*.tar.gz