From 6beeb1b708550be0d4a53b272283e17e5e35fe17 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 17:01:30 +0200 Subject: Adding upstream version 2.4.57. Signed-off-by: Daniel Baumann --- docs/manual/mod/mod_isapi.html.en | 371 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 371 insertions(+) create mode 100644 docs/manual/mod/mod_isapi.html.en (limited to 'docs/manual/mod/mod_isapi.html.en') diff --git a/docs/manual/mod/mod_isapi.html.en b/docs/manual/mod/mod_isapi.html.en new file mode 100644 index 0000000..a7d2f51 --- /dev/null +++ b/docs/manual/mod/mod_isapi.html.en @@ -0,0 +1,371 @@ + + + + + +mod_isapi - Apache HTTP Server Version 2.4 + + + + + + + +
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Modules | Directives | FAQ | Glossary | Sitemap

+

Apache HTTP Server Version 2.4

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Apache Module mod_isapi

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Available Languages:  en  | + fr  | + ko 

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+ + + + +
Description:ISAPI Extensions within Apache for Windows
Status:Base
Module Identifier:isapi_module
Source File:mod_isapi.c
Compatibility:Win32 only
+

Summary

+ +

This module implements the Internet Server extension API. It + allows Internet Server extensions (e.g. ISAPI .dll + modules) to be served by Apache for Windows, subject to the + noted restrictions.

+ +

ISAPI extension modules (.dll files) are written by third + parties. The Apache Group does not author these modules, so we + provide no support for them. Please contact the ISAPI's author + directly if you are experiencing problems running their ISAPI + extension. Please do not post such problems to + Apache's lists or bug reporting pages.

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Usage

+ +

In the server configuration file, use + the AddHandler directive to + associate ISAPI files with the isapi-handler handler, and map + it to them with their file extensions. To enable any .dll file to be + processed as an ISAPI extension, edit the httpd.conf file and add the + following line:

+ 
AddHandler isapi-handler .dll
+ + +
In older versions of the Apache server, + isapi-isa was the proper handler name, rather than + isapi-handler. As of 2.3 development versions of the Apache + server, isapi-isa is no longer valid. You will need to + change your configuration to use isapi-handler + instead.
+ +

There is no capability within the Apache server to leave a + requested module loaded. However, you may preload and keep a + specific module loaded by using the following syntax in your + httpd.conf:

+ 
ISAPICacheFile c:/WebWork/Scripts/ISAPI/mytest.dll
+ + +

Whether or not you have preloaded an ISAPI extension, all + ISAPI extensions are governed by the same permissions and + restrictions as CGI scripts. That is, Options ExecCGI must be set for the + directory that contains the ISAPI .dll file.

+ +

Review the Additional Notes and the Programmer's Journal for additional details + and clarification of the specific ISAPI support offered by + mod_isapi.

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+

Additional Notes

+ +

Apache's ISAPI implementation conforms to all of the ISAPI + 2.0 specification, except for some "Microsoft-specific" + extensions dealing with asynchronous I/O. Apache's I/O model + does not allow asynchronous reading and writing in a manner + that the ISAPI could access. If an ISA tries to access + unsupported features, including async I/O, a message is placed + in the error log to help with debugging. Since these messages + can become a flood, the directive ISAPILogNotSupported + Off exists to quiet this noise.

+ +

Some servers, like Microsoft IIS, load the ISAPI extension + into the server and keep it loaded until memory usage is too + high, or unless configuration options are specified. Apache + currently loads and unloads the ISAPI extension each time it is + requested, unless the ISAPICacheFile directive is specified. + This is inefficient, but Apache's memory model makes this the + most effective method. Many ISAPI modules are subtly + incompatible with the Apache server, and unloading these + modules helps to ensure the stability of the server.

+ +

Also, remember that while Apache supports ISAPI Extensions, + it does not support ISAPI Filters. Support for + filters may be added at a later date, but no support is planned + at this time.

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+

Programmer's Journal

+ +

If you are programming Apache 2.0 mod_isapi + modules, you must limit your calls to ServerSupportFunction + to the following directives:

+ +
+
HSE_REQ_SEND_URL_REDIRECT_RESP
+
Redirect the user to another location.
+ This must be a fully qualified URL (e.g. + http://server/location).
+ +
HSE_REQ_SEND_URL
+
Redirect the user to another location.
+ This cannot be a fully qualified URL, you are not allowed to + pass the protocol or a server name (e.g. simply + /location).
+ This redirection is handled by the server, not the + browser.
+

Warning

+

In their recent documentation, Microsoft appears to have + abandoned the distinction between the two + HSE_REQ_SEND_URL functions. Apache continues to treat + them as two distinct functions with different requirements + and behaviors.

+
+ +
HSE_REQ_SEND_RESPONSE_HEADER
+
Apache accepts a response body following the header if it + follows the blank line (two consecutive newlines) in the + headers string argument. This body cannot contain NULLs, + since the headers argument is NULL terminated.
+ +
HSE_REQ_DONE_WITH_SESSION
+
Apache considers this a no-op, since the session will be + finished when the ISAPI returns from processing.
+ +
HSE_REQ_MAP_URL_TO_PATH
+
Apache will translate a virtual name to a physical + name.
+ +
HSE_APPEND_LOG_PARAMETER
+
+ This logged message may be captured in any of the following + logs: + + + +

The first option, the %{isapi-parameter}n component, + is always available and preferred.

+
+ +
HSE_REQ_IS_KEEP_CONN
+
Will return the negotiated Keep-Alive status.
+ +
HSE_REQ_SEND_RESPONSE_HEADER_EX
+
Will behave as documented, although the fKeepConn + flag is ignored.
+ +
HSE_REQ_IS_CONNECTED
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Will report false if the request has been aborted.
+
+ +

Apache returns FALSE to any unsupported call to + ServerSupportFunction, and sets the + GetLastError value to + ERROR_INVALID_PARAMETER.

+ +

ReadClient retrieves the request body exceeding the + initial buffer (defined by ISAPIReadAheadBuffer). Based on the + ISAPIReadAheadBuffer setting (number of bytes + to buffer prior to calling the ISAPI handler) shorter requests are sent + complete to the extension when it is invoked. If the request is + longer, the ISAPI extension must use ReadClient to + retrieve the remaining request body.

+ +

WriteClient is supported, but only with the + HSE_IO_SYNC flag or no option flag (value of + 0). Any other WriteClient request + will be rejected with a return value of FALSE, and a + GetLastError value of + ERROR_INVALID_PARAMETER.

+ +

GetServerVariable is supported, although extended server + variables do not exist (as defined by other servers.) All the + usual Apache CGI environment variables are available from + GetServerVariable, as well as the ALL_HTTP + and ALL_RAW values.

+ +

Since httpd 2.0, mod_isapi supports additional + features introduced in later versions of the ISAPI specification, + as well as limited emulation of async I/O and the + TransmitFile semantics. Apache httpd also supports preloading + ISAPI .dlls for performance.

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ISAPIAppendLogToErrors Directive

+ + + + + + + + +
Description:Record HSE_APPEND_LOG_PARAMETER requests from +ISAPI extensions to the error log
Syntax:ISAPIAppendLogToErrors on|off
Default:ISAPIAppendLogToErrors off
Context:server config, virtual host, directory, .htaccess
Override:FileInfo
Status:Base
Module:mod_isapi
+

Record HSE_APPEND_LOG_PARAMETER requests from ISAPI + extensions to the server error log.

+ +
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ISAPIAppendLogToQuery Directive

+ + + + + + + + +
Description:Record HSE_APPEND_LOG_PARAMETER requests from +ISAPI extensions to the query field
Syntax:ISAPIAppendLogToQuery on|off
Default:ISAPIAppendLogToQuery on
Context:server config, virtual host, directory, .htaccess
Override:FileInfo
Status:Base
Module:mod_isapi
+

Record HSE_APPEND_LOG_PARAMETER requests from ISAPI + extensions to the query field (appended to the CustomLog %q + component).

+ +
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ISAPICacheFile Directive

+ + + + + + +
Description:ISAPI .dll files to be loaded at startup
Syntax:ISAPICacheFile file-path [file-path] +...
Context:server config, virtual host
Status:Base
Module:mod_isapi
+

Specifies a space-separated list of file names to be loaded + when the Apache server is launched, and remain loaded until the + server is shut down. This directive may be repeated for every + ISAPI .dll file desired. The full path name of each file should + be specified. If the path name is not absolute, it will be treated + relative to ServerRoot.

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ISAPIFakeAsync Directive

+ + + + + + + + +
Description:Fake asynchronous support for ISAPI callbacks
Syntax:ISAPIFakeAsync on|off
Default:ISAPIFakeAsync off
Context:server config, virtual host, directory, .htaccess
Override:FileInfo
Status:Base
Module:mod_isapi
+

While set to on, asynchronous support for ISAPI callbacks is + simulated.

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ISAPILogNotSupported Directive

+ + + + + + + + +
Description:Log unsupported feature requests from ISAPI +extensions
Syntax:ISAPILogNotSupported on|off
Default:ISAPILogNotSupported off
Context:server config, virtual host, directory, .htaccess
Override:FileInfo
Status:Base
Module:mod_isapi
+

Logs all requests for unsupported features from ISAPI + extensions in the server error log. This may help administrators + to track down problems. Once set to on and all desired ISAPI modules + are functioning, it should be set back to off.

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ISAPIReadAheadBuffer Directive

+ + + + + + + + +
Description:Size of the Read Ahead Buffer sent to ISAPI +extensions
Syntax:ISAPIReadAheadBuffer size
Default:ISAPIReadAheadBuffer 49152
Context:server config, virtual host, directory, .htaccess
Override:FileInfo
Status:Base
Module:mod_isapi
+

Defines the maximum size of the Read Ahead Buffer sent to + ISAPI extensions when they are initially invoked. All remaining + data must be retrieved using the ReadClient callback; some + ISAPI extensions may not support the ReadClient function. + Refer questions to the ISAPI extension's author.

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Available Languages:  en  | + fr  | + ko 

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Comments

Notice:
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