Overview of the Apache TPF Port
[ Configuration Files
| What's Available
| CGI Scripts
| Options
| Syslog
| Porting Notes ]
This version of Apache includes changes allowing it to run
on IBM's EBCDIC-based TPF
(Transaction Processing Facility) operating system.
Unless otherwise noted TPF version 4.1 PUT09 is
required.
Refer to install-tpf.html for
step-by-step installation instructions.
This port builds upon the EBCDIC
changes previously made to Apache.
Apache Configuration Files
The distributed configuration files (httpd.conf-dist and
mime.types, both located in the conf subdirectory) work on TPF.
Performance considerations may dictate setting KeepAlive to
"Off" (the default is "On") or lowering the Timeout value from
the default 300 seconds (5 minutes) in order to reduce the
number of active ECBs on your system.
What's Available in this Version
The Apache organization provides online documentation
describing the various modules and components of the
server.
Components/modules tested on TPF:
- alloc.c
- ap_base64.c
- ap_checkpass.c
- ap_cpystrn.c
- ap_ebcdic.c
- ap_fnmatch.c
- ap_md5c.c
- ap_sha1.c
- ap_signal.c
- ap_slack.c
- ap_snprintf.c
- buff.c
- buildmark.c
- gen_test.char.c
- gen_uri_delims.c
- htpasswd.c (requires PUT10)
- http_config.c
- http_core.c
- http_log.c
- http_main.c
- http_protocol.c
- http_request.c
- http_vhost.c
- logresolve.c (requires PUT10)
- mod_access.c (Use of mod_access directives
"allow from" & "deny from"
with host names (verses ip addresses) requires
PUT10)
- mod_actions.c
- mod_alias.c
- mod_asis.c
- mod_auth.c
- mod_auth_anon.c
- mod_autoindex.c
- mod_cern_meta.c
- mod_cgi.c (requires PUT10)
- mod_digest.c
- mod_dir.c
- mod_env.c
- mod_example.c
- mod_expires.c
- mod_headers.c
- mod_imap.c
- mod_include.c (CGI execution requires TPF version 4.1
PUT10)
- mod_info.c
- mod_log_agent.c
- mod_log_config.c
- mod_log_referer.c
- mod_mime.c
- mod_mime_magic.c
- mod_negotiation.c
- mod_put.c
(third party module)
- mod_proxy.c
- mod_setenvif.c
- mod_speling.c
- mod_status.c
- mod_tpf_shm_static.c (third party module, requires
PUT10)
- mod_unique_id.c (requires PUT10)
- mod_userdir.c
- mod_usertrack.c
- os.c
- os-inline.c
- proxy_cache.c
- proxy_connect.c
- proxy_ftp.c
- proxy_http.c
- proxy_util.c
- regular expression parser
- regular expression test tool (requires
PUT10)
- rfc1413.c
- rotatelogs.c (requires PUT10; if PJ27214 implemented be sure to apply PJ28367)
- syslog (requires PUT13; see install
and usage instructions)
- util.c
- util_date.c
- util_md5.c
- util_script.c
- util_uri.c
Components/modules not yet supported on TPF:
- htdigest.c
- lib/expat-lite
- lib/sdbm
- mod_auth_digest.c
- mod_rewrite.c
- mod_vhost_alias.c
Components/modules that don't apply or that probably won't
ever be available on TPF:
- ab.c
- ap_getpass.c
- mod_auth_db.c
- mod_auth_dbm.c
- mod_auth_db.module
- mod_mmap_static.c
- mod_so.c
- suexec.c
How to Use CGI Scripts
The following is a very simple example of a CGI script
("Hello World") and the necessary steps to run it.
Refer to the mod_cgi
module for additional information.
Add necessary directives to httpd.conf:
Example:
ScriptLog logs/script_log
ScriptAlias /cgi-bin/ /usr/local/apache/cgi-bin/
A request for
https://myserver/cgi-bin/filename.cgi
would cause the server to run the script
/usr/local/apache/cgi-bin/filename.cgi
Create the CGI script:
For this example QZZ1 is the name of the TPF
program that will be executed by the CGI script.
The directory path must match what is in the httpd.conf file
for ScriptAlias directive.
zfile echo "#!QZZ1" >
/usr/local/apache/cgi-bin/filename.cgi
zfile cat
/usr/local/apache/cgi-bin/filename.cgi
(this should display #!QZZ1)
Mark the script as executable:
zfile chmod 755
/usr/local/apache/cgi-bin/filename.cgi
Create, load, and activate a loadset containing the CGI
program (QZZ1xx):
/** QZZ1-- simple "Hello world" program to demonstrate
basic CGI output **/
#include <stdio.h>
void main() {
/** Print the CGI response header, required for all
HTML output. **/
/** Note the extra \n, to send the blank line. **/
printf("Content-type: text/html\n\n");
/** Print the HTML response page to stdout. **/
printf("<html>\n");
printf("<head><title> CGI Output
</title></head>\n");
printf("<body>\n");
printf("<h1> Hello world </h1> \n");
printf("</body>\n");
printf("</html>\n");
}
Request the CGI script from a browser:
https://myserver/cgi-bin/filename.cgi
How to Use Apache's "Dash" Options
Overview of Apache's "dash" options:
Apache can be invoked with various options, such as "-f".
Some of these options display information about the server or perform syntax checks
but they don't actually start the server.
These "information only" options are useful with TPF's ZFILE command line feature:
-h, -l, -L, -S, -t, -T, -v, and -V.
Another option, -X, is used when actually running the server.
It is passed to Apache through the ZINET XPARM field since ZINET is the only way to start the server on TPF.
A third group of options apply to both the informational displays (ZFILE) and
running the server (ZINET XPARM): -d, -D and -f.
The rest of Apache's options are either not applicable or are not supported on TPF.
Using dash options requires PJ27277 which shipped on PUT13.
Table of supported Apache options
Option
| ZFILE |
ZINET
| Description |
-d path |
ZFILE |
ZINET |
Set the initial value for the ServerRoot directive. |
-D define |
ZFILE |
ZINET |
Set a configuration parameter which can be used with <IfDefine>...</IfDefine> sections in the configuration file to conditionally skip or process commands. |
-f filename |
ZFILE |
ZINET |
Use an alternate configuration file instead of the default conf/httpd.conf file. |
-h |
ZFILE |
|
List a short summary of available command line options then exit.
Note that this outputs all options, not just those supported on TPF. |
-l |
ZFILE |
|
List modules compiled into the server then exit. |
-L |
ZFILE |
|
List available configuration directives then exit. Note that this outputs all configuration directives, not just those supported on TPF. |
-S |
ZFILE |
|
Show the settings as parsed from the configuration file then exit. Currently Apache only shows the virtual host settings. |
-t |
ZFILE |
|
Run syntax tests for configuration files with document root checks then exit. |
-T |
ZFILE |
|
Run syntax tests for configuration files without document root checks then exit. |
-v |
ZFILE |
|
Show the version number then exit. |
-V |
ZFILE |
|
Show the version number and various compile settings then exit. |
-X |
|
ZINET |
Run in single-process mode for internal debugging purposes only.
The parent process does not fork any children. |
See https://httpd.apache.org/docs/programs/httpd.html
for more information about these command line options.
Setup for ZFILE examples
Ensure Apache (CHTA) is loaded
Create the httpd script:
zfile echo "#!CHTA" > /bin/httpd
zfile cat /bin/httpd (this should display
#!CHTA)
Mark the script as executable:
zfile chmod 755 /bin/httpd
(See "ZFILE-Activate a TPF Segment or Script" in
the Operations guide for more information: https://www.ibm.com/tpf/pubs/tpfpubs.htm.)
ZFILE example 1
zfile httpd -v
FILE0001I 11.43.09 START OF DISPLAY FROM httpd
-v
Server version: Apache/1.3.20 (TPF)
Server built: May 23 2001 09:39:22
END OF DISPLAY
ZFILE example 2
zfile httpd -t -f
/usr/local/apache/conf/alt.conf
FILE0002I 11.47.26 START OF ERROR DISPLAY FROM httpd
-t ...
Syntax OK
END OF DISPLAY
ZINET XPARM example
This example uses an alternate configuration file called /usr/local/apache/conf/alt.conf.
Transfer the alternate configuration file to your TPF test system.
zinet add s-apache pgm-chta model-daemon user-root xparm--f conf/alt.conf
zinet start s-apache
(See "ZINET ADD-Add an Internet Server Application Entry" and
"ZINET ALTER-Change an Internet Server Application Entry" in
the Operations guide for more information about using the XPARM field:
https://www.ibm.com/tpf/pubs/tpfpubs.htm.)
Syslog Daemon
Syslog overview:
The syslog daemon is a server process that provides a message logging facility for application and system processes.
It can be used to write messages to log files or to tapes.
See TPF Transmission Control Protocol/Internet Protocol for detailed information about using the syslog daemon on TPF:
https://www.ibm.com/tpf/pubs/tpfpubs.htm.
And see the Apache ErrorLog directive documentation
for details on how to use syslog with Apache.
Syslog capabilities were added with PJ27214 which shipped with PUT13.
You must follow the syslog specific installation instructions
in order to have the option of using syslog with Apache.
Tips on using syslog with your Apache error log:
This section provides some tips on using syslog with Apache.
It is not meant to replace the syslog documentation in the TPF TCP/IP publication.
- The syslog daemon will not create files. If you are logging to a file (as specified in the syslog.conf configuration file) that file must already exist and
have permissions that allow the syslog daemon to write to it.
- You must restart the syslog daemon for it to recognize changes to its syslog.conf configuration file.
- The syslog daemon must be active prior to starting Apache.
- To indicate you want to use syslog with your Apache error log add the following directive to your httpd.conf file:
"ErrorLog syslog:facility" where facility is "local0" through "local7".
- Apache will default the facility to "local7" if you omit the facility name from the ErrorLog directive (that is "ErrorLog syslog").
- The syslog facility name must be one that is recognized by both Apache and the syslog.h header file.
The facility names "local0" through "local7" are explicitly set aside for your use.
- Although "local0" through "local7" are recommended user facility names, here is the complete list of names recognized
by both Apache and TPF's syslog.h: auth, cron, daemon, kern, local0, local1, local2, local3, local4, local5, local6, local7,
lpr, mail, news, syslog, user, and uucp.
- You won't see the normal Apache startup/shutdown messages when you use syslog with your Apache error log.
- Syslog does not support TCP/IP Offload devices (ZCLAW)
Porting Notes
Changes made due to differences between UNIX and TPF's
process models:
- Signals: On TPF a signal that is sent to a process
remains unhandled until the process explicitly requests that
signals be handled using the tpf_process_signals()
function. Additionally, the default action for an alarm on
TPF is to take an OPR-7777 dump and exit. (On UNIX the
default is the equivalent of exit() with no dump
taken.) These differences necessitated a few
modifications:
-
- bypass the use of ap_block_alarms() &
ap_unblock_alarms()
- add tpf_process_signals() calls
- add select() calls to prevent
blocking.
Find that function...
Some simple functions & definitions initially needed to be
added on TPF, such as FD_SET(). We've put these in
src/os/tpf/os.h for now.
EBCDIC changes:
TPF-specific conversion tables between US-ASCII and EBCDIC
(character set IBM-1047 to be exact) were created.
Miscellaneous, minor changes:
Various minor changes (such as casting) were made due to
differences in how some functions are implemented on
TPF.
[ top
| Configuration Files
| What's Available
| CGI Scripts
| Options
| Syslog
| Porting Notes ]