昨天白天用官方示例在主機安裝了FF插件,然而晚上回寢室用VS2013並沒有成功,不禁想起了那句話“程序員都是好男人,他們每天都會反省自己,我又錯在哪了”。
言歸正傳,今天的目標是閱讀理解FF插件官方文檔,我這菜雞一般的英語水平勉強能應付。
一、Initialization
當一個插件加載了,在創建第一個實例之前就會調用NPError NP_Initialize(void) {};
分配內存資源給所有實例使用。
對應的NP_Shutdown函數是在最後一個實例銷燬糊調用,用來釋放NP_Initialize分配的內存資源
/* Define global variable to hold the user agent string. */
static char* userAgent = NULL;
/* Initialize function. */
NPError NP_Initialize(void)
{
/* Get the user agent from the browser. */
char* result = NPN_UserAgent();
if (result == NULL) return NPERR_OUT_OF_MEMORY_ERROR;
/* Allocate some memory so that you can keep a copy of it. */
userAgent = (char*) NPN_MemAlloc(strlen(result) + 1);
if (userAgent == NULL) return NPERR_OUT_OF_MEMORY_ERROR;
/* Copy the string to your memory. */
strcpy(userAgent, result);
return NPERR_NO_ERROR;
}
/* Shutdown function */
NPError NP_Shutdown(void)
{
/* Delete the memory you allocated. */
if (userAgent != NULL)
NPN_MemFree(userAgent);
return NPERR_NO_ERROR;
}
userAgent 是什麼,“用戶代理”?算了暫時不管了,反正它是個全局靜態指針變量。指的是NPN_UserAgent()得到的資源。
二、MIMEType
在初始化的時候,瀏覽器會去數MIMEType類型的已被註冊的插件。接着看看怎麼註冊插件吧。
“A MIME type is made up of a major type (such as application or image) and a minor type, for example, image/jpeg.If you define a new MIME type for a plug-in, you must register it with IETF (Internet Engineering Task Force). Until your new MIME type is registered, preface its name with “x-“, for example, image/x-nwim.”
IETF看不懂。我的FF瀏覽器application已經存在,所以我昨天修改的MIMEType沒有加“x-”。
緊接着往後看我就炸了!
When a Gecko-based browser starts up, it checks certain directories for plug-ins, in this order:
Windows
1、Directory pointed to by MOZ_PLUGIN_PATH environment variable.
2、%APPDATA%\Mozilla\plugins, where %APPDATA% denotes per-user Application Data directory.
3、Plug-ins within toolkit bundles.
4、Profile directory\plugins, where Profile directory is a user profile directory.
5、Directories pointed to by HKEY_CURRENT_USER\Software\MozillaPlugins*\Path registry value, where * can be replaced by any name.
6、Directories pointed to by HKEY_LOCAL_MACHINE\Software\MozillaPlugins*\Path registry value, where * can be replaced by any name.
奇怪啊,最開始我在
HKEY_LOCAL_MACHINE\Software\MozillaPlugins\添加@mozilla.com.cn/test可是瀏覽器並沒有檢測到我的插件啊,反而在HKEY_CURRENT_USER\Software\MozillaPlugins\添加時纔有效果。現在再試一次,還是如此!
算了不較真了,除了最後一條,其他的在我電腦上都好用。
Mac OS X
1、~/Library/Internet Plug-Ins.
2、/Library/Internet Plug-Ins.
3、/System/Library/Frameworks/JavaVM.framework/Versions/Current/Resources.
4、Plug-ins within toolkit bundles.
5、Profile directory/plugins, where Profile directory is a user profile directory.
Linux
1、 Directory pointed to by MOZ_PLUGIN_PATH environment variable. For example:
#!/bin/bash
export MOZ_PLUGIN_PATH=/usr/lib64/mozilla/plugins
exec /usr/lib64/firefox/firefox
Which /usr/lib64/mozilla/plugins this is path for folder with plugins, /usr/lib64/firefox/firefox this is path for firefox (binary file).
2、 ~/.mozilla/plugins.
3、 /usr/lib/mozilla/plugins (on 64-bit systems, /usr/lib64/mozilla/plugins is used instead).