shell 脚本学习笔记

@think3r 2020-12-22 11:07:24

0x00

# 摘抄于 vlc 编译脚本
if [ -z "$MAKEFLAGS" ]; then
    UNAMES=$(uname -s)
    MAKEFLAGS=
    if which nproc >/dev/null; then
        MAKEFLAGS=-j$(nproc)
    elif [ "$UNAMES" = "Darwin" ] && which sysctl >/dev/null; then
        MAKEFLAGS=-j$(sysctl -n machdep.cpu.thread_count)
    fi
fi

if [ "${ANDROID_ABI}" = "arm" ] ; then
    ANDROID_ABI="armeabi-v7a"
elif [ "${ANDROID_ABI}" = "arm64" ] ; then
    ANDROID_ABI="arm64-v8a"
fi

if [ -f $SRC_DIR/src/libvlc.h ]; then
    VLC_SRC_DIR="$SRC_DIR"
elif [ -d $SRC_DIR/vlc ]; then
    VLC_SRC_DIR=$SRC_DIR/vlc
else
    echo "Could not find vlc sources"
    exit 1
fi

if [ ! -f "$1" ]; then
    echo_props > "$1"
    return 0
fi

init_local_props local.properties || { echo "Error initializing local.properties"; exit $?; }

# shell 中写文件 https://blog.csdn.net/werewolf2017/article/details/109818114
rm -rf $VLC_OUT_PATH/Android.mk
cat << 'EOF' > $VLC_OUT_PATH/Android.mk
LOCAL_PATH := $(call my-dir)
include $(CLEAR_VARS)
LOCAL_MODULE    := libvlc
LOCAL_SRC_FILES := libvlcjni-modules.c libvlcjni-symbols.c dummy.cpp
LOCAL_LDFLAGS := -L$(VLC_CONTRIB)/lib
LOCAL_LDLIBS := \
    $(VLC_MODULES) \
    $(VLC_BUILD_DIR)/lib/.libs/libvlc.a \
    $(VLC_BUILD_DIR)/src/.libs/libvlccore.a \
    $(VLC_BUILD_DIR)/
EOF

• if 判断语句 :
  • -z 变量为空判断;
  • "${ANDROID_ABI}" = "arm" 判断字符串相等, 只用一个 = 号;
  • -f 文件存在判断;
  • -d 文件夹存在判断;
  • ! 结果取反;
• uname -s 操作系统;
• which nproc >/dev/null 是否存在制定命令;
  • nproc 等价于 sysctl -n machdep.cpu.thread_count 都是获取 cpu 核数;
  • which 等价于 command -v 都是查找命令位置的;
• || 执行对应命令, 有错误时, 执行之后的命令;

时间计算

if [ "$(uname -s)" = "Linux" ]; then
    date_execute="date"
elif [ "$(uname -s)" = "Darwin" ]; then
    date_execute="gdate"
fi

if command -v $date_execute > /dev/null; then
    startTime=$($date_execute +'%Y-%m-%d %H:%M:%S')
    #执行程序
    endTime=$($date_execute +'%Y-%m-%d %H:%M:%S')
    start_seconds=$($date_execute --date="$startTime" +%s);
    end_seconds=$($date_execute --date="$endTime" +%s);
    echo -e "_____> using ${bldgrn}" $((end_seconds-start_seconds)) "${txtrst} s"
fi

ijk 源码文件名修改

#!/bin/sh

find . -path "*ijk*" | while read line ;
do
    DistName=$(echo $line|sed 's/ijk/think/g')
	echo "Src: $line ; DistName: $DistName"
	if [ -d $line ]; then
	    mkdir -p $DistName
	elif [ -f $line ]; then
	    DistFileDir=${DistName%/*}
		if [ ! -d $DistFileDir ]; then
		    mkdir -p $DistFileDir
		fi
	    cp  $line $DistName
	fi
done