
gflags Module

Jiri Kuthan

Edited by

Daniel-Constantin Mierla

   Copyright © 2004 FhG FOKUS
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   Table of Contents
   1. User's Guide

        1.1. Overview
        1.2. Dependencies
        1.3. Exported Parameters

              1.3.1. initial (string)

        1.4. Exported Functions

              1.4.1. set_gflag(flag)
              1.4.2. reset_gflag(flag)
              1.4.3. is_gflag(flag)

        1.5. FIFO Commands

              1.5.1. set_gflag
              1.5.2. reset_gflag
              1.5.3. is_gflag

   2. Developer's Guide
   3. Frequently Asked Questions

   List of Examples
   1-1. initial parameter usage
   1-2. set_gflag() usage
   1-3. reset_gflag() usage
   1-4. is_gflag() usage
   1-5. set_gflag usage
   1-6. reset_gflag usage
   1-7. set_gflag usage
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Chapter 1. User's Guide

1.1. Overview

   gflags module (global flags) keeps a bitmap of flags in shared
   memory and may be used to change behaviour of server based on
   value of the flags. E.g., if (is_gflag("1")) {
   t_relay_to_udp("10.0.0.1","5060"); } else {
   t_relay_to_udp("10.0.0.2","5060"); }.

   The benefit of this module is the value of the switch flags
   can be manipulated by external applications such as web
   interface or command line tools. The size of bitmap is 32
   (unsigned int).

   The module exports commands to FIFO server that can be used to
   change the global flags via FIFO interface. The FIFO commands
   are: "set_gflag", "reset_gflag" and "is_gflag".
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1.2. Dependencies

   The module depends on the following modules (in the other
   words the listed modules must be loaded before this module):

     * none
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1.3. Exported Parameters

1.3.1. initial (string)

   The initial value of global flags bitmap.

   Default value is "0".

   Example 1-1. initial parameter usage
modparam("gflags", "initial", "15)
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1.4. Exported Functions

1.4.1. set_gflag(flag)

   Set the bit at the position "flag" in global flags.

   "flag" can have a value from the range 1..31.

   This function can be used from REQUEST_ROUTE, FAILURE_ROUTE,
   ONREPLY_ROUTE.

   Example 1-2. set_gflag() usage
...
set_gflag("4");
...
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1.4.2. reset_gflag(flag)

   Reset the bit at the position "flag" in global flags.

   This function can be used from REQUEST_ROUTE, FAILURE_ROUTE,
   ONREPLY_ROUTE.

   Example 1-3. reset_gflag() usage
...
reset_gflag("4");
...
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1.4.3. is_gflag(flag)

   Check if bit at the position "flag" in global flags is set.

   This function can be used from REQUEST_ROUTE, FAILURE_ROUTE,
   ONREPLY_ROUTE.

   Example 1-4. is_gflag() usage
...
if(is_gflag("4"))
{
        log("global flag 4 is set\n");
} else {
        log("global flag 4 is not set\n");
};
...
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1.5. FIFO Commands

1.5.1. set_gflag

   Set the value of a flag to 1. The function accepts one
   parameter which is the number of the flag to be set.

   Example 1-5. set_gflag usage
...
$ openserctl fifo set_gflag 1
...
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1.5.2. reset_gflag

   Reset the value of a flag to 0. The function accepts one
   parameter which is the number of the flag to be reset.

   Example 1-6. reset_gflag usage
...
$ openserctl fifo reset_gflag 1
...
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1.5.3. is_gflag

   Return the status of a flag. The FIFO function would return
   TRUE if the flag is set and FALSE if it is not set. The only
   parameter of this function is the number of the flag.

   Example 1-7. set_gflag usage
...
$ openserctl fifo is_gflag 1
...
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Chapter 2. Developer's Guide

   The module does not provide any API to use in other OpenSER
   modules.
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Chapter 3. Frequently Asked Questions

   3.1. Where can I find more about OpenSER?
   3.2. Where can I post a question about this module?
   3.3. How can I report a bug?

   3.1. Where can I find more about OpenSER?

   Take a look at http://openser.org/.

   3.2. Where can I post a question about this module?

   First at all check if your question was already answered on
   one of our mailing lists:

     * User Mailing List -
       http://openser.org/cgi-bin/mailman/listinfo/users
     * Developer Mailing List -
       http://openser.org/cgi-bin/mailman/listinfo/devel

   E-mails regarding any stable OpenSER release should be sent to
   <users@openser.org> and e-mails regarding development versions
   should be sent to <devel@openser.org>.

   If you want to keep the mail private, send it to
   <team@openser.org>.

   3.3. How can I report a bug?

   Please follow the guidelines provided at:
   http://openser.org/bugs.
