mod_proxy/5668: Patch for streaming servers and long running cgi-scripts

[Kim Bisgaard <ki...@dmi.dk>]

>Number:         5668
>Category:       mod_proxy
>Synopsis:       Patch for streaming servers and long running cgi-scripts
>Confidential:   no
>Severity:       critical
>Priority:       medium
>Responsible:    apache
>State:          open
>Class:          change-request
>Submitter-Id:   apache
>Arrival-Date:   Sat Jan 29 08:50:00 PST 2000
>Closed-Date:
>Last-Modified:
>Originator:     kib@dmi.dk
>Release:        1.3.11
>Organization:
apache
>Environment:
any
>Description:
Apache proxy module ruins the marvelous new facility in apache 1.3 of 
delivering the output from scripts un-buffered - thus instantly. This 
property is vital in long running cgi-scripts (see bug report 4733, 1166), 
and in streaming servers (see bug report 4566)
>How-To-Repeat:
See above emntioned bug reports.
>Fix:
Utilize the "Pragma: no-cache" or HTTP 1.1 "Cache-Control: no-cache" to signify
both no-caching and no-buffering in proxy module.
--- apache_1.9.11/src/modules/proxy/proxy_http.c
+++ apache_1.9.11/src/modules/proxy/proxy_http.c
@@ -472,6  +472,16 @@
      if ((datestr = ap_table_get(resp_hdrs, "URI")) != NULL)
  	ap_table_set(resp_hdrs, "URI", proxy_location_reverse_map(r, datestr));

+ /* If "Pragma: no-cache" or "Cache-Control: no-cache"
+  * set nocache and make reply un-buffered to enshure timely delivery */
+     if (((pragma = ap_table_get(resp_hdrs, "Pragma")) != NULL &&
+ 	 ap_proxy_liststr(pragma, "no-cache")) ||
+ 	((pragma = ap_table_get(resp_hdrs, "Cache-Control")) != NULL &&
+ 	 ap_proxy_liststr(pragma, "no-cache"))) {
+       nocache = 1;
+       r->connection->client->flags &= ~B_WR;
+     }

  /* check if NoCache directive on this host */
      for (i = 0; i < conf->nocaches->nelts; i++) {
>Release-Note:
>Audit-Trail:
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