引言
今天在教別人使用protobuf的時候，無意中發現了一個php cli模式下的詭異問題，費了老半天的找到解決方法了，這里拿出來分享下。
問題描述
我們這邊最先引入了protobuf協議，使用的是allegro/php-protobuf這個擴展安裝的。這幾天其他同事也要用到這個，於是我將protobuf生成php類庫文件的部分放到了一個公共的位置/data/php_proto/文件夾下，里面有這些內容，
drwsrwxr-x 2 yanruitao users 4096 10月 14 17:05 Dmp
-rwxrwxr-x 1 yanruitao users 472 10月 10 17:59 dmp.proto
drwsrwxr-x 2 yanruitao users 4096 10月 10 17:54 ProtobufCompiler
-rwxrwxr-x 1 yanruitao users 2969 3月 9 2015 protoc-php.php
后面兩個是必須的，生成pb協議實現類庫文件時會用到，前面兩個是一個簡單的例子，使用也很簡單，就像下面這樣。
php protoc-php.php -n --psr dmp.proto //-n是使用命名空間，--psr是使用psr-4標准
等同事用的時候發現會報錯，
PHP Warning: file_put_contents(pb_proto_dmp.php): failed to open stream: Permission denied in /data/php_proto/ProtobufCompiler/ProtobufParser.php on line 309
同事問我的時候我直接說，加上sudo就可以了，結果加上sudo問題更嚴重了，本來裝好的擴展程序加載不成功，經過一番排查發下有下面這么一個問題：
$yanruitao: php -i | grep 'php.ini'
$yanruitao: sudo php -i | grep 'php.ini'
兩種用戶加載的不是同一個配置文件，普通用戶加載的是/usr/local/php/lib/php.ini，而root用戶加載的是/etc/php.ini這個文件，我看了下這兩個文件內容不一致，哈哈，好開心，趕緊把先把/etc/php.ini備份，/usr/local/php/lib/php.ini復制到/etc/php.ini，復制完了之后，我再使用的時候嚇我一跳，報了一大堆錯誤:
PHP Warning: PHP Startup: Unable to load dynamic library '/usr/local/php/lib/php/extensions/no-debug-non-zts-20100525/web_stub_cntl.so' - /usr/local/php/lib/php/extensions/no-debug-non-zts-20100525/web_stub_cntl.so: undefined symbol: zend_new_interned_string in Unknown on line 0
Warning: PHP Startup: Unable to load dynamic library '/usr/local/php/lib/php/extensions/no-debug-non-zts-20100525/web_stub_cntl.so' - /usr/local/php/lib/php/extensions/no-debug-non-zts-20100525/web_stub_cntl.so: undefined symbol: zend_new_interned_string in Unknown on line 0
PHP Warning: PHP Startup: test: Unable to initialize module
Module compiled with module API=20100525
PHP compiled with module API=20090626
These options need to match
in Unknown on line 0
Warning: PHP Startup: test: Unable to initialize module
Module compiled with module API=20100525
PHP compiled with module API=20090626
These options need to match
in Unknown on line 0
PHP Warning: PHP Startup: Unable to load dynamic library '/usr/local/php/lib/php/extensions/no-debug-non-zts-20100525/protobuf.so' - /usr/local/php/lib/php/extensions/no-debug-non-zts-20100525/protobuf.so: undefined symbol: zend_new_interned_string in Unknown on line 0
Warning: PHP Startup: Unable to load dynamic library '/usr/local/php/lib/php/extensions/no-debug-non-zts-20100525/protobuf.so' - /usr/local/php/lib/php/extensions/no-debug-non-zts-20100525/protobuf.so: undefined symbol: zend_new_interned_string in Unknown on line 0
PHP Warning: PHP Startup: Unable to load dynamic library '/usr/local/php/lib/php/extensions/no-debug-non-zts-20100525/imagick.so' - /usr/local/php/lib/php/extensions/no-debug-non-zts-20100525/imagick.so: undefined symbol: zend_new_interned_string in Unknown on line 0
Warning: PHP Startup: Unable to load dynamic library '/usr/local/php/lib/php/extensions/no-debug-non-zts-20100525/imagick.so' - /usr/local/php/lib/php/extensions/no-debug-non-zts-20100525/imagick.so: undefined symbol: zend_new_interned_string in Unknown on line 0
PHP Warning: PHP Startup: Unable to load dynamic library '/data/boss/phpredis-develop/modules/redis.so' - /data/boss/phpredis-develop/modules/redis.so: undefined symbol: zend_new_interned_string in Unknown on line 0
Warning: PHP Startup: Unable to load dynamic library '/data/boss/phpredis-develop/modules/redis.so' - /data/boss/phpredis-develop/modules/redis.so: undefined symbol: zend_new_interned_string in Unknown on line 0
PHP Warning: PHP Startup: Unable to load dynamic library '/usr/local/php/lib/php/extensions/no-debug-non-zts-20100525/curl.so' - /usr/local/php/lib/php/extensions/no-debug-non-zts-20100525/curl.so: cannot open shared object file: No such file or directory in Unknown on line 0
Warning: PHP Startup: Unable to load dynamic library '/usr/local/php/lib/php/extensions/no-debug-non-zts-20100525/curl.so' - /usr/local/php/lib/php/extensions/no-debug-non-zts-20100525/curl.so: cannot open shared object file: No such file or directory in Unknown on line 0
PHP Warning: PHP Startup: Unable to load dynamic library '/usr/local/php/lib/php/extensions/no-debug-non-zts-20100525/fileinfo.so' - /usr/local/php/lib/php/extensions/no-debug-non-zts-20100525/fileinfo.so: cannot open shared object file: No such file or directory in Unknown on line 0
Warning: PHP Startup: Unable to load dynamic library '/usr/local/php/lib/php/extensions/no-debug-non-zts-20100525/fileinfo.so' - /usr/local/php/lib/php/extensions/no-debug-non-zts-20100525/fileinfo.so: cannot open shared object file: No such file or directory in Unknown on line 0
PHP Warning: PHP Startup: Unable to load dynamic library '/usr/local/php/lib/php/extensions/no-debug-non-zts-20100525/gd.so' - /usr/local/php/lib/php/extensions/no-debug-non-zts-20100525/gd.so: cannot open shared object file: No such file or directory in Unknown on line 0
Warning: PHP Startup: Unable to load dynamic library '/usr/local/php/lib/php/extensions/no-debug-non-zts-20100525/gd.so' - /usr/local/php/lib/php/extensions/no-debug-non-zts-20100525/gd.so: cannot open shared object file: No such file or directory in Unknown on line 0
PHP Warning: PHP Startup: Unable to load dynamic library '/usr/local/php/lib/php/extensions/no-debug-non-zts-20100525/json.so' - /usr/local/php/lib/php/extensions/no-debug-non-zts-20100525/json.so: cannot open shared object file: No such file or directory in Unknown on line 0
Warning: PHP Startup: Unable to load dynamic library '/usr/local/php/lib/php/extensions/no-debug-non-zts-20100525/json.so' - /usr/local/php/lib/php/extensions/no-debug-non-zts-20100525/json.so: cannot open shared object file: No such file or directory in Unknown on line 0
PHP Warning: PHP Startup: Unable to load dynamic library '/usr/local/php/lib/php/extensions/no-debug-non-zts-20100525/phar.so' - /usr/local/php/lib/php/extensions/no-debug-non-zts-20100525/phar.so: cannot open shared object file: No such file or directory in Unknown on line 0
Warning: PHP Startup: Unable to load dynamic library '/usr/local/php/lib/php/extensions/no-debug-non-zts-20100525/phar.so' - /usr/local/php/lib/php/extensions/no-debug-non-zts-20100525/phar.so: cannot open shared object file: No such file or directory in Unknown on line 0
PHP Warning: PHP Startup: Unable to load dynamic library '/data/boss/phpredis-develop/modules/redis.so' - /data/boss/phpredis-develop/modules/redis.so: undefined symbol: zend_new_interned_string in Unknown on line 0
Warning: PHP Startup: Unable to load dynamic library '/data/boss/phpredis-develop/modules/redis.so' - /data/boss/phpredis-develop/modules/redis.so: undefined symbol: zend_new_interned_string in Unknown on line 0
PHP Warning: PHP Startup: Unable to load dynamic library '/usr/local/php/lib/php/extensions/no-debug-non-zts-20100525/zip.so' - /usr/local/php/lib/php/extensions/no-debug-non-zts-20100525/zip.so: cannot open shared object file: No such file or directory in Unknown on line 0
Warning: PHP Startup: Unable to load dynamic library '/usr/local/php/lib/php/extensions/no-debug-non-zts-20100525/zip.so' - /usr/local/php/lib/php/extensions/no-debug-non-zts-20100525/zip.so: cannot open shared object file: No such file or directory in Unknown on line 0
protoc-php.php requires protobuf extension installed to run
這讓我摸不着頭腦了。
時間過去了好久，沒有發現任何突破，卻發現了一個備用的解決這個問題的方案，修改/data/php_proto/文件夾權限為0775，其他普通用戶就可以直接使用了，不用加sudo(這個是我的錯，忘記修改文件夾權限了，這也讓我發現了這個詭異的問題)
chmod -R 0775 /data/php_proto
看了報的這些錯誤，大部分都是擴展的問題，有的是擴展加載不成功，有的是擴展不存在，我就納悶了，為什么普通用戶可以，root用戶就不可以。
看到root用戶php -i的時候，配置文件的地方跟非root用戶有不一致的地方：
//非root
Scan this dir for additional .ini files => (none)
Additional .ini files parsed => (none)
//root
Scan this dir for additional .ini files => /etc/php.d
Additional .ini files parsed => /etc/php.d/curl.ini,
......
命名加載的是一樣的配置文件怎么加載之后的內容就不一樣呢？
搜了半天，知道了報的錯里面有部分是跟這個有關系的，但是這個在哪里修改搜了老久也沒有搜到。
忽然想到root用戶和非root用戶使用的php可執行文件是不一致的
root => /usr/bin/php
非root => /usr/local/bin/php
嘗試着對這兩個文件使用了php -v，結果下了我一跳，root用戶的版本是5.3.3，非root用戶是5.4.6，呵呵，我就呵呵了，誰部署的環境~，坑人啊。
嘗試着將原有/usr/bin/php備份后，復制/usr/local/bin/php過來覆蓋掉，在使用php -v發現版本一致了，也不報錯了，再次去執行php protoc-php.php -n --psr dmp.proto，發現all is well，至此問題解決。
糾結了半天，結果就是版本的問題。
總結
多思考，多換個角度思考。
做事要完善啊，別給后輩留下一些詭異問題←_←。