PHPCPP安装以及hello world

学习了一段时间做PHP扩展开发，由于C的难度较大，内存回收，指针每一个都可以能让初学者望而却步，加上C开发效率太低，小型企业对于这种高大上的开发，还是少触碰为好。但是有时候PHP开发执行效率确实太低，而且存在很大的资源浪费，并且这个又是无法避免的（比如excel），混合开发让项目的迁移和可维护性都降低了。

一次偶然机会发现了PHPCPP，C++开发PHP的扩展，C++不用说了吧！执行效率最接近C的语言。最主要的是PHPCPP大大的降低了PHP扩展的开发难度。以前开发扩展，初始化项目对于小白来说都可能是个灾难，而PHPCPP对于希望开发扩展的PHPER可以说是一个福音。

在不接触PHP底层的情况下，采用PHPCPP是一个很好的选择方案。下面废话不多说，上干货。

首先选择一个你常用的linux版本，然后下载PHPCPP

 git clone https://github.com/CopernicaMarketingSoftware/PHP-CPP.git

然后编译并安装PHPCPP

make &&sudo  make install

这样PHPCPP就安装成功了。

从PHPCPP下载一个空项目http://www.php-cpp.com/EmptyE...

这里说明一下，默认最新PHPCPP是只支持PHP7的，如果需要支持PHP5.X需要下载他的另外一个版本，API一样，只是sdk不同，所以采用PHPCPP开发的扩展源码是相通的，只是需要在对应版本编译。

言归正传，空项目中的Makefile，可以修改NAME，这个是你的扩展文件名称，其他都保持不变

#
#   Makefile template
#
#   This is an example Makefile that can be used by anyone who is building
#   his or her own PHP extensions using the PHP-CPP library. 
#
#   In the top part of this file we have included variables that can be
#   altered to fit your configuration, near the bottom the instructions and
#   dependencies for the compiler are defined. The deeper you get into this
#   file, the less likely it is that you will have to change anything in it.
#

#
#   Name of your extension
#
#   This is the name of your extension. Based on this extension name, the
#   name of the library file (name.so) and the name of the config file (name.ini)
#   are automatically generated
#

NAME                =   yourextension

#
#   Php.ini directories
#
#   In the past, PHP used a single php.ini configuration file. Today, most
#   PHP installations use a conf.d directory that holds a set of config files,
#   one for each extension. Use this variable to specify this directory.
#
#   In Ubuntu 14.04 Apache 2.4 is used, which uses the mods-available directory
#   instead of a conf.d directory. In 16.04 the directory changed yet again.
#   This has to be checked.
#

UBUNTU_MAJOR  := $(shell /usr/bin/lsb_release -r -s | cut -f1 -d.)
OVER_SIXTEEN  := $(shell echo "${UBUNTU_MAJOR} >= 16" | bc)
OVER_FOURTEEN := $(shell echo "${UBUNTU_MAJOR} >= 14" | bc)

ifeq (${OVER_SIXTEEN}, 1)
    INI_DIR     =   /etc/php/7.0/mods-available/
else ifeq (${OVER_FOURTEEN}, 1)
    INI_DIR     =   /etc/php5/mods-available/
else
    INI_DIR     =   /etc/php5/conf.d/
endif

#
#   The extension dirs
#
#   This is normally a directory like /usr/lib/php5/20121221 (based on the 
#   PHP version that you use. We make use of the command line 'php-config' 
#   instruction to find out what the extension directory is, you can override
#   this with a different fixed directory
#

EXTENSION_DIR       =   $(shell php-config --extension-dir)

#
#   The name of the extension and the name of the .ini file
#
#   These two variables are based on the name of the extension. We simply add
#   a certain extension to them (.so or .ini)
#

EXTENSION           =   ${NAME}.so
INI                 =   ${NAME}.ini

#
#   Compiler
#
#   By default, the GNU C++ compiler is used. If you want to use a different
#   compiler, you can change that here. You can change this for both the 
#   compiler (the program that turns the c++ files into object files) and for
#   the linker (the program that links all object files into the single .so
#   library file. By default, g++ (the GNU C++ compiler) is used for both.
#

COMPILER            =   g++
LINKER              =   g++

#
#   Compiler and linker flags
#
#   This variable holds the flags that are passed to the compiler. By default, 
#   we include the -O2 flag. This flag tells the compiler to optimize the code, 
#   but it makes debugging more difficult. So if you're debugging your application, 
#   you probably want to remove this -O2 flag. At the same time, you can then 
#   add the -g flag to instruct the compiler to include debug information in
#   the library (but this will make the final libphpcpp.so file much bigger, so
#   you want to leave that flag out on production servers).
#
#   If your extension depends on other libraries (and it does at least depend on
#   one: the PHP-CPP library), you should update the LINKER_DEPENDENCIES variable
#   with a list of all flags that should be passed to the linker.
#

COMPILER_FLAGS      =   -Wall -c -O2 -std=c++11 -fpic -o
LINKER_FLAGS        =   -shared
LINKER_DEPENDENCIES =   -lphpcpp

#
#   Command to remove files, copy files and create directories.
#
#   I've never encountered a *nix environment in which these commands do not work. 
#   So you can probably leave this as it is
#

RM                  =   rm -f
CP                  =   cp -f
MKDIR               =   mkdir -p

#
#   All source files are simply all *.cpp files found in the current directory
#
#   A built-in Makefile macro is used to scan the current directory and find 
#   all source files. The object files are all compiled versions of the source
#   file, with the .cpp extension being replaced by .o.
#

SOURCES             =   $(wildcard *.cpp)
OBJECTS             =   $(SOURCES:%.cpp=%.o)

#
#   From here the build instructions start
#

all:                    ${OBJECTS} ${EXTENSION}

${EXTENSION}:           ${OBJECTS}
                        ${LINKER} ${LINKER_FLAGS} -o $@ ${OBJECTS} ${LINKER_DEPENDENCIES}

${OBJECTS}:
                        ${COMPILER} ${COMPILER_FLAGS} $@ ${@:%.o=%.cpp}

install:        
                        ${CP} ${EXTENSION} ${EXTENSION_DIR}
                        ${CP} ${INI} ${INI_DIR}

clean:
                        ${RM} ${EXTENSION} ${OBJECTS}

main.c源码

#include <phpcpp.h>
#include <iostream>

void myFunction()
{
    Php::out << "hello world" << std::endl;
}

extern "C" {
    PHPCPP_EXPORT void *get_module() {
        static Php::Extension extension("my_extension", "1.0");
        extension.add<myFunction>("myFunction");
        return extension;
    }
}

这样一个扩展代码就完成了，执行编译

make

然后将生成的xxx.so拷贝到PHP扩展目录，并在PHP.INI加入

extension=yourextension.so

执行php -m查看是否加载了扩展，如果已经成功加载那么，就会显示my_extension在里面了

php  -m

那么PHP中如何调用呢？如果没有使用命名空间那么可以这样

<?php
   myFunction();

如果使用了需要加上\

<?php
 \myFunction();

这样第一个扩展就完成了。

以后会每周至少更新两篇关于PHPCPP的文章记录并分享自己的使用PHPCPP的开发经验。