从谷歌的github下载protobuf（3.x版本）
1、安装homebrew

/usr/bin/ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"

2、执行以下命令

sudo xcode-select --install

brew install autoconf

brew install automake

brew install libtool

cd到protobuf根目录
第一次需要运行./autogen.sh（只需第一次运行）

./autogen.sh

./configure

make

make check

make install

之后运行如下sh脚本

#!/bin/bash

echo "$(tput setaf 2)"
echo "###################################################################"
echo "# Preparing to build Google Protobuf"
echo "###################################################################"
echo "$(tput sgr0)"
export SED=`which sed`
# The results will be stored relative to the location
# where you stored this script, **not** relative to
# the location of the protobuf git repo.
PREFIX=`pwd`/protobuf
if [ -d ${PREFIX} ]
then
    rm -rf "${PREFIX}"
fi
mkdir -p "${PREFIX}/platform"

# A "YES" value will build the latest code from GitHub on the master branch.
# A "NO" value will use the 2.6.0 tarball downloaded from googlecode.com.
USE_GIT_MASTER=NO

PROTOBUF_GIT_URL=https://github.com/google/protobuf.git
PROTOBUF_GIT_DIRNAME=protobuf
PROTOBUF_VERSION=3.2.1
PROTOBUF_RELEASE_URL=https://codeload.github.com/google/protobuf/zip/v${PROTOBUF_VERSION}
PROTOBUF_RELEASE_DIRNAME=protobuf-${PROTOBUF_VERSION}

# if BUILD_MACOSX_X86_64=NO,you must install protoc in your system,because we need protoc
BUILD_MACOSX_X86_64=YES

BUILD_I386_IOSSIM=YES
BUILD_X86_64_IOSSIM=NO

BUILD_IOS_ARMV7=YES
BUILD_IOS_ARMV7S=YES
BUILD_IOS_ARM64=YES

PROTOBUF_SRC_DIR=/Users/games/Desktop/protobuf-3.2.1

DARWIN=darwin16.5.0

XCODEDIR=`xcode-select --print-path`
IOS_SDK_VERSION=`xcrun --sdk iphoneos --show-sdk-version`
MIN_SDK_VERSION=8.0

MACOSX_PLATFORM=`xcrun --sdk macosx --show-sdk-platform-path`
MACOSX_SYSROOT=`xcrun --sdk macosx --show-sdk-path`

IPHONEOS_PLATFORM=`xcrun --sdk iphoneos --show-sdk-platform-path`
IPHONEOS_SYSROOT=`xcrun --sdk iphoneos --show-sdk-path`

IPHONESIMULATOR_PLATFORM=`xcrun --sdk iphonesimulator --show-sdk-platform-path`
IPHONESIMULATOR_SYSROOT=`xcrun --sdk iphonesimulator --show-sdk-path`

# Uncomment if you want to see more information about each invocation
# of clang as the builds proceed.
# CLANG_VERBOSE="--verbose"

CC=clang
CXX=clang

CFLAGS="${CLANG_VERBOSE} -DNDEBUG -g -O0 -pipe -fPIC -fcxx-exceptions"
CXXFLAGS="${CLANG_VERBOSE} ${CFLAGS} -std=c++11 -stdlib=libc++"

LDFLAGS="-stdlib=libc++"
LIBS="-lc++ -lc++abi"

echo "PREFIX ..................... ${PREFIX}"
echo "USE_GIT_MASTER ............. ${USE_GIT_MASTER}"
echo "PROTOBUF_GIT_URL ........... ${PROTOBUF_GIT_URL}"
echo "PROTOBUF_GIT_DIRNAME ....... ${PROTOBUF_GIT_DIRNAME}"
echo "PROTOBUF_VERSION ........... ${PROTOBUF_VERSION}"
echo "PROTOBUF_RELEASE_URL ....... ${PROTOBUF_RELEASE_URL}"
echo "PROTOBUF_RELEASE_DIRNAME ... ${PROTOBUF_RELEASE_DIRNAME}"
echo "BUILD_MACOSX_X86_64 ........ ${BUILD_MACOSX_X86_64}"
echo "BUILD_I386_IOSSIM .......... ${BUILD_I386_IOSSIM}"
echo "BUILD_X86_64_IOSSIM ........ ${BUILD_X86_64_IOSSIM}"
echo "BUILD_IOS_ARMV7 ............ ${BUILD_IOS_ARMV7}"
echo "BUILD_IOS_ARMV7S ........... ${BUILD_IOS_ARMV7S}"
echo "BUILD_IOS_ARM64 ............ ${BUILD_IOS_ARM64}"
echo "PROTOBUF_SRC_DIR ........... ${PROTOBUF_SRC_DIR}"
echo "DARWIN ..................... ${DARWIN}"
echo "XCODEDIR ................... ${XCODEDIR}"
echo "IOS_SDK_VERSION ............ ${IOS_SDK_VERSION}"
echo "MIN_SDK_VERSION ............ ${MIN_SDK_VERSION}"
echo "MACOSX_PLATFORM ............ ${MACOSX_PLATFORM}"
echo "MACOSX_SYSROOT ............. ${MACOSX_SYSROOT}"
echo "IPHONEOS_PLATFORM .......... ${IPHONEOS_PLATFORM}"
echo "IPHONEOS_SYSROOT ........... ${IPHONEOS_SYSROOT}"
echo "IPHONESIMULATOR_PLATFORM ... ${IPHONESIMULATOR_PLATFORM}"
echo "IPHONESIMULATOR_SYSROOT .... ${IPHONESIMULATOR_SYSROOT}"
echo "CC ......................... ${CC}"
echo "CFLAGS ..................... ${CFLAGS}"
echo "CXX ........................ ${CXX}"
echo "CXXFLAGS ................... ${CXXFLAGS}"
echo "LDFLAGS .................... ${LDFLAGS}"
echo "LIBS ....................... ${LIBS}"

while true; do
    read -p "Proceed with build? (y/n) " yn
    case $yn in
        [Yy]* ) break;;
        [Nn]* ) exit;;
        * ) echo "Please answer yes or no.";;
    esac
done

###################################################################
# This section contains the build commands to create the native
# protobuf library for Mac OS X.  This is done first so we have
# a copy of the protoc compiler.  It will be used in all of the
# susequent iOS builds.
###################################################################

echo "$(tput setaf 2)"
echo "###################################################################"
echo "# x86_64 for Mac OS X"
echo "###################################################################"
echo "$(tput sgr0)"

if [ "${BUILD_MACOSX_X86_64}" == "YES" ]
then
    (
        cd ${PROTOBUF_SRC_DIR}
        make distclean
        ./configure --disable-shared --prefix=${PREFIX} --exec-prefix=${PREFIX}/platform/x86_64-mac "CC=${CC}" "CFLAGS=${CFLAGS} -arch x86_64" "CXX=${CXX}" "CXXFLAGS=${CXXFLAGS} -arch x86_64" "LDFLAGS=${LDFLAGS}" "LIBS=${LIBS}"
        make
        make check
        make install
    )
    PROTOC=${PREFIX}/platform/x86_64-mac/bin/protoc
else
    PROTOC=protoc
fi

if [ ! -n `which $PROTOC` ]; then
 echo 'error:command protoc not available'
 exit 1
fi

###################################################################
# This section contains the build commands for each of the 
# architectures that will be included in the universal binaries.
###################################################################

echo "$(tput setaf 2)"
echo "###########################"
echo "# i386 for iPhone Simulator"
echo "###########################"
echo "$(tput sgr0)"

if [ "${BUILD_I386_IOSSIM}" == "YES" ]
then
    (
        cd ${PROTOBUF_SRC_DIR}
        make distclean
        ./configure --build=x86_64-apple-${DARWIN} --host=i386-apple-${DARWIN} --with-protoc=${PROTOC} --disable-shared --prefix=${PREFIX} --exec-prefix=${PREFIX}/platform/i386-sim "CC=${CC}" "CFLAGS=${CFLAGS} -mios-simulator-version-min=${MIN_SDK_VERSION} -arch i386 -isysroot ${IPHONESIMULATOR_SYSROOT}" "CXX=${CXX}" "CXXFLAGS=${CXXFLAGS} -mios-simulator-version-min=${MIN_SDK_VERSION} -arch i386 -isysroot ${IPHONESIMULATOR_SYSROOT}" LDFLAGS="-arch i386 -mios-simulator-version-min=${MIN_SDK_VERSION} ${LDFLAGS} -L${IPHONESIMULATOR_SYSROOT}/usr/lib/ -L${IPHONESIMULATOR_SYSROOT}/usr/lib/system" "LIBS=${LIBS}"
        make
        make install
    )
fi

echo "$(tput setaf 2)"
echo "#############################"
echo "# x86_64 for iPhone Simulator"
echo "#############################"
echo "$(tput sgr0)"

if [ "${BUILD_X86_64_IOSSIM}" == "YES" ]
then
    (
        cd ${PROTOBUF_SRC_DIR}
        make distclean
        ./configure --build=x86_64-apple-${DARWIN} --host="x86_64-apple-${DARWIN}" --with-protoc=${PROTOC} --disable-shared --prefix=${PREFIX} --exec-prefix=${PREFIX}/platform/x86_64-sim "CC=${CC}" "CFLAGS=${CFLAGS} -mios-simulator-version-min=${MIN_SDK_VERSION} -arch x86_64 -isysroot ${IPHONESIMULATOR_SYSROOT}" "CXX=${CXX}" "CXXFLAGS=${CXXFLAGS} -mios-simulator-version-min=${MIN_SDK_VERSION} -arch x86_64 -isysroot ${IPHONESIMULATOR_SYSROOT}" LDFLAGS="-arch x86_64 -mios-simulator-version-min=${MIN_SDK_VERSION} ${LDFLAGS} -L${IPHONESIMULATOR_SYSROOT}/usr/lib/ -L${IPHONESIMULATOR_SYSROOT}/usr/lib/system" "LIBS=${LIBS}"
        make
        make install
    )
fi

echo "$(tput setaf 2)"
echo "##################"
echo "# armv7 for iPhone"
echo "##################"
echo "$(tput sgr0)"

if [ "${BUILD_IOS_ARMV7}" == "YES" ]
then
    (
        cd ${PROTOBUF_SRC_DIR}
        make distclean
        ./configure --build=x86_64-apple-${DARWIN} --host=armv7-apple-${DARWIN} --with-protoc=${PROTOC} --disable-shared --prefix=${PREFIX} --exec-prefix=${PREFIX}/platform/armv7-ios "CC=${CC}" "CFLAGS=${CFLAGS} -miphoneos-version-min=${MIN_SDK_VERSION} -arch armv7 -isysroot ${IPHONEOS_SYSROOT}" "CXX=${CXX}" "CXXFLAGS=${CXXFLAGS} -arch armv7 -isysroot ${IPHONEOS_SYSROOT}" LDFLAGS="-arch armv7 -miphoneos-version-min=${MIN_SDK_VERSION} ${LDFLAGS}" "LIBS=${LIBS}"
        make
        make install
    )
fi

echo "$(tput setaf 2)"
echo "###################"
echo "# armv7s for iPhone"
echo "###################"
echo "$(tput sgr0)"

if [ "${BUILD_IOS_ARMV7S}" == "YES" ]
then
    (
        cd ${PROTOBUF_SRC_DIR}
        make distclean
        ./configure --build=x86_64-apple-${DARWIN} --host=armv7s-apple-${DARWIN} --with-protoc=${PROTOC} --disable-shared --prefix=${PREFIX} --exec-prefix=${PREFIX}/platform/armv7s-ios "CC=${CC}" "CFLAGS=${CFLAGS} -miphoneos-version-min=${MIN_SDK_VERSION} -arch armv7s -isysroot ${IPHONEOS_SYSROOT}" "CXX=${CXX}" "CXXFLAGS=${CXXFLAGS} -miphoneos-version-min=${MIN_SDK_VERSION} -arch armv7s -isysroot ${IPHONEOS_SYSROOT}" LDFLAGS="-arch armv7s -miphoneos-version-min=${MIN_SDK_VERSION} ${LDFLAGS}" "LIBS=${LIBS}"
        make
        make install
    )
fi

echo "$(tput setaf 2)"
echo "##################"
echo "# arm64 for iPhone"
echo "##################"
echo "$(tput sgr0)"

if [ "${BUILD_IOS_ARM64}" == "YES" ]
then
    (
        cd ${PROTOBUF_SRC_DIR}
        make distclean
        ./configure --build=x86_64-apple-${DARWIN} --host=arm --with-protoc=${PROTOC} --disable-shared --prefix=${PREFIX} --exec-prefix=${PREFIX}/platform/arm64-ios "CC=${CC}" "CFLAGS=${CFLAGS} -miphoneos-version-min=${MIN_SDK_VERSION} -arch arm64 -isysroot ${IPHONEOS_SYSROOT}" "CXX=${CXX}" "CXXFLAGS=${CXXFLAGS} -miphoneos-version-min=${MIN_SDK_VERSION} -arch arm64 -isysroot ${IPHONEOS_SYSROOT}" LDFLAGS="-arch arm64 -miphoneos-version-min=${MIN_SDK_VERSION} ${LDFLAGS}" "LIBS=${LIBS}"
        make
        make install
    )
fi

echo "$(tput setaf 2)"
echo "###################################################################"
echo "# Create Universal Libraries and Finalize the packaging"
echo "###################################################################"
echo "$(tput sgr0)"

(
    cd ${PREFIX}/platform
    mkdir universal
    ALL_LIB=""
    for LIB in `find . -name libprotobuf.a`; do
        ALL_LIB="${ALL_LIB} ${LIB}"
    done
    if [ ! -z "${ALL_LIB}" ]; then 
        lipo ${ALL_LIB} -create -output universal/libprotobuf.a
    fi

    ALL_LIB=""
    for LIB in `find . -name libprotobuf-lite.a`; do
        ALL_LIB="${ALL_LIB} ${LIB}"
    done
    if [ ! -z "${ALL_LIB}" ]; then 
        lipo ${ALL_LIB} -create -output universal/libprotobuf-lite.a
    fi

    echo ${ALL_LIB}
)

(
    cd ${PREFIX}
    mkdir bin
    mkdir lib
    if [ "${BUILD_MACOSX_X86_64}" == "YES" ]
        then
        cp -r platform/x86_64-mac/bin/protoc bin
        cp -r platform/x86_64-mac/lib/* lib
    fi
    cp -r platform/universal/* lib
    lipo -info lib/libprotobuf.a
    lipo -info lib/libprotobuf-lite.a
    open lib/
)

if [ "${USE_GIT_MASTER}" == "YES" ]
then
    if [ -d "${PREFIX}-master" ]
    then
        rm -rf "${PREFIX}-master"
    fi
    mv "${PREFIX}" "${PREFIX}-master"
else
    if [ -d "${PREFIX}-${PROTOBUF_VERSION}" ]
    then
        rm -rf "${PREFIX}-${PROTOBUF_VERSION}"
    fi
    mv "${PREFIX}" "${PREFIX}-${PROTOBUF_VERSION}"
fi

echo Done!