gflags Module

Jiri Kuthan

Edited by

Daniel-Constantin Mierla

   Copyright  2004 FhG FOKUS
     __________________________________________________________

   Table of Contents
   1. User's Guide

        1.1. Overview
        1.2. Dependencies
        1.3. Exported Parameters

              1.3.1. initial (integer)

        1.4. Exported Functions

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

        1.5. MI Commands

              1.5.1. set_gflag
              1.5.2. reset_gflag
              1.5.3. is_gflag
              1.5.4. get_gflags

   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. is_gflag usage
   1-8. get_gflags 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. Example:
        if (is_gflag("1")) {
                t_relay("udp:10.0.0.1:5060");
        } else {
                t_relay("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.

   The module exports external commands that can be used to change
   the global flags via Management Interface. The MI commands are:
   "set_gflag", "reset_gflag" and "is_gflag".
     __________________________________________________________

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 (integer)

   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 and BRANCH_ROUTE.

   Example 1-2. set_gflag() usage
...
set_gflag("4");
...
     __________________________________________________________

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 and BRANCH_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 and BRANCH_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. MI Commands

   Functions that check or change some flags accepts one parameter
   which is the flag bitmap/mask specifing the corresponding
   flags. It is not possible to specify directly the flag position
   that should be changed as in the functions available in the
   routing script.
     __________________________________________________________

1.5.1. set_gflag

   Set the value of some flags to 1.

   The parameter value must be a number in decimal or hexa format

   Example 1-5. set_gflag usage
...
$ openserctl fifo set_gflag 1
$ openserctl fifo set_gflag 0x3
...
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1.5.2. reset_gflag

   Reset the value of some flags to 0.

   The parameter value must be a number in decimal or hexa format

   Example 1-6. reset_gflag usage
...
$ openserctl fifo reset_gflag 1
$ openserctl fifo reset_gflag 0x3
...
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1.5.3. is_gflag

   Return the status of a set of flags.

   The function returns TRUE if all the flags from the set are set
   and FALSE if at least one is not set.

   Example 1-7. is_gflag usage
...
$ openserctl fifo set_gflag 1024
$ openserctl fifo is_gflag 1024
TRUE
$ openserctl fifo is_gflag 1025
TRUE
$ openserctl fifo is_gflag 1023
FALSE
$ openserctl fifo set_gflag 0x10
$ openserctl fifo is_gflag 1023
TRUE
$ openserctl fifo is_gflag 1007
FALSE
$ openserctl fifo is_gflag 16
TRUE
...
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1.5.4. get_gflags

   Return the bitmap with all flags. The function gets no
   parameters and returns the bitmap in hexa and decimal format.

   Example 1-8. get_gflags usage
...
$ openserctl fifo get_gflags
0x3039
12345
...
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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://sourceforge.net/tracker/?group_id=139143.
