MAMP下面的php添加openssl扩展

在MAMP集成开发环境下测试支付宝sdk时，总是在签名参数的地方返回空，参数格式都是正确的，是因为openssl扩展没有开。

原文地址：http://jaspan.com/openssl-support-php-under-mamp

1. Build the PHP openssl extension (or, if you are really lazy, just download the one I built).
   Download PHP from php.net. I'm using MAMP 1.6 (haven't bothered to upgrade) which uses PHP 5.2.1 which, it turns out, does not build properly on MacOS X 10.5 Leopard. So I used PHP 5.2.5 instead which works fine; this is also the version that MAMP 1.7 uses. Newer versions of 5.2 would probably also work.
   Using Terminal, extract, configure, and build PHP, specifically requesting a shared openssl library:

 tar -xzf php-5.2.5.tar.gz
 cd php-5.2.5
 ./configure --with-openssl=shared% make

2. Install the PHP openssl extension
   From the same directory in which you ran make:

cp modules/openssl.so /Applications/MAMP/bin/php5/lib/php/extensions/no-debug-non-zts-20050922/

The date in the final directory name will depend on which version of MAMP/PHP you have installed.

3. Edit /Applications/MAMP/conf/php5/php5.ini.
   Search for lines that contain "extension=" and add the line

extension=openssl.so

That's it!