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== Summary ==
== Summary ==
OpenLDAP will not ship non-threaded version of libldap. Instead, libldap will be built with the same threading support as libldap_r.
OpenLDAP will not ship non-threaded version of libldap. Instead, symlinks will be provided for runtime libraries to keep working, and all software built with libldap will be effectively built with libldap_r.
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== Current status ==
== Current status ==
* Targeted release: [[Releases/29 | Fedora 29 ]]  
[[Category:ChangeAcceptedF34]]
[[Category:SystemWideChange]]
* Targeted release: [[Releases/34 | Fedora 34 ]]  
* Last updated: <!-- this is an automatic macro — you don't need to change this line -->  {{REVISIONYEAR}}-{{REVISIONMONTH}}-{{REVISIONDAY2}}  
* Last updated: <!-- this is an automatic macro — you don't need to change this line -->  {{REVISIONYEAR}}-{{REVISIONMONTH}}-{{REVISIONDAY2}}  
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* FESCo issue: [https://pagure.io/fesco/issue/2436 #2436]
* Tracker bug: [https://bugzilla.redhat.com/show_bug.cgi?id=1537260 #1537260]
* Tracker bug: [https://bugzilla.redhat.com/show_bug.cgi?id=1537260 #1537260]
* Release notes tracker: [https://pagure.io/fedora-docs/release-notes/issue/198 #198]


== Detailed Description ==
== Detailed Description ==
After this change the non-threaded version of libldap will not be shipped any more. Instead, this library will rather be built the same way as the threaded libldap_r. This has been previously discussed in [[https://bugzilla.redhat.com/show_bug.cgi?id=1370065 Bugzilla]] and other distributions where this change already happened. Upstream still supports non-threaded version of their library as it might be used on processors where threads are not supported. However, when these two versions happen to be loaded at the same time (as discussed about Curl in the Bugzilla) symbol names overlap which may result in unpredictable behaviour. Immediate solution would be to symlink libldap to libldap_r, however SONAME of the library would be the same, hence breaking dependencies of other packages. For that reason the solution hereby proposed should be the most convenient one.
For historical reasons OpenLDAP is currently shipped with two libraries which provide the very same functionality, differing only in support for multi-threading. If these are both loaded in the same runtime this may lead to unpredictable behaviour due to identical symbol naming. Upstream ceased from supporting the non-threaded variant in the next major release, however in the current stable version it is still supported as it might be used on processors where threads are not supported.
 
After this change the non-threaded version of the library (`libldap`) will not be shipped any more. Instead, this library will rather be linked to its threaded counterpart (`libldap_r`). The runtime symlinks will be moved to a separate `openldap-compat` subpackage so that any package linked with `libldap` (i.e. not `libldap_r`) will be clearly indentifiable by this "new" dependency. The `openldap-devel` package will provide `libldap.so` as a symlink to `libldap_r.so` so that all rebuilt packages are linked to the same library. Initial mass rebuild is anticipated to discover potential build issues as well as to eliminate the actual issues caused by both libraries being loaded at the same time.
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== Benefit to Fedora ==
== Benefit to Fedora ==
No potential unexpected issues due to symbol overlap.
No potential unexpected issues caused by symbol overlap.
<!-- What is the benefit to the platform?  If this is a major capability update, what has changed?  If this is a new functionality, what capabilities does it bring? Why will Fedora become a better distribution or project because of this proposal?-->
<!-- What is the benefit to the platform?  If this is a major capability update, what has changed?  If this is a new functionality, what capabilities does it bring? Why will Fedora become a better distribution or project because of this proposal?-->


== Scope ==
== Scope ==
* Proposal owners: update SPEC file so that non-threaded libldap is replaced with threaded one.
* Proposal owners: update SPEC file as described in the Detailed Description.
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== How To Test ==
== How To Test ==
libldap and libldap_r should export same symbols, obviously except for SONAME. Any applications linking to OpenLDAP libraries may test that their LDAP related functionality works.
libldap and libldap_r should export the same symbols. Any applications linking to OpenLDAP libraries may test that their LDAP related functionality works.
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<!-- If you cannot complete your feature by the final development freeze, what is the backup plan?  This might be as simple as "Revert the shipped configuration".  Or it might not (e.g. rebuilding a number of dependent packages).  If you feature is not completed in time we want to assure others that other parts of Fedora will not be in jeopardy.  -->
* Contingency mechanism: Revert the change. <!-- REQUIRED FOR SYSTEM WIDE CHANGES -->
* Contingency mechanism: Revert the change in OpenLDAP's SPEC file and rebuild it. Any packages succesfully rebuilt after the SPEC change are expected to be working properly, and if not they shall be rebuilt after the SPEC revert.<!-- REQUIRED FOR SYSTEM WIDE CHANGES -->
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* Contingency deadline: beta freeze. <!-- REQUIRED FOR SYSTEM WIDE CHANGES -->
* Contingency deadline: beta freeze. <!-- REQUIRED FOR SYSTEM WIDE CHANGES -->
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Release Notes are not required for initial draft of the Change Proposal but has to be completed by the Change Freeze.  
Release Notes are not required for initial draft of the Change Proposal but has to be completed by the Change Freeze.  
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OpenLDAP does not ship non-threaded version of libldap any more, libldap brings now the very same features libldap_r does.
OpenLDAP does not ship non-threaded version of libldap any more, and it is seamlessly replaced by the threaded libldap_r. No additional action from development should be required.
 
[[Category:ChangeReadyForWrangler]]
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[[Category:SystemWideChange]]

Latest revision as of 00:44, 22 August 2020


OpenLDAP without Non-threaded Libraries

Summary

OpenLDAP will not ship non-threaded version of libldap. Instead, symlinks will be provided for runtime libraries to keep working, and all software built with libldap will be effectively built with libldap_r.

Owner

  • Name: Matus Honek
  • Email: mhonek@redhat.com
  • Release notes owner:

Current status

Detailed Description

For historical reasons OpenLDAP is currently shipped with two libraries which provide the very same functionality, differing only in support for multi-threading. If these are both loaded in the same runtime this may lead to unpredictable behaviour due to identical symbol naming. Upstream ceased from supporting the non-threaded variant in the next major release, however in the current stable version it is still supported as it might be used on processors where threads are not supported.

After this change the non-threaded version of the library (libldap) will not be shipped any more. Instead, this library will rather be linked to its threaded counterpart (libldap_r). The runtime symlinks will be moved to a separate openldap-compat subpackage so that any package linked with libldap (i.e. not libldap_r) will be clearly indentifiable by this "new" dependency. The openldap-devel package will provide libldap.so as a symlink to libldap_r.so so that all rebuilt packages are linked to the same library. Initial mass rebuild is anticipated to discover potential build issues as well as to eliminate the actual issues caused by both libraries being loaded at the same time.

Benefit to Fedora

No potential unexpected issues caused by symbol overlap.

Scope

  • Proposal owners: update SPEC file as described in the Detailed Description.
  • Other developers: None. Issues should not occur.
  • Policies and guidelines: None.
  • Trademark approval: (not needed for this Change)

Upgrade/compatibility impact

No issues should occur.


How To Test

libldap and libldap_r should export the same symbols. Any applications linking to OpenLDAP libraries may test that their LDAP related functionality works.

User Experience

User should not notice anything.

Dependencies

None.


Contingency Plan

  • Contingency mechanism: Revert the change in OpenLDAP's SPEC file and rebuild it. Any packages succesfully rebuilt after the SPEC change are expected to be working properly, and if not they shall be rebuilt after the SPEC revert.
  • Contingency deadline: beta freeze.
  • Blocks release? No.
  • Blocks product? No.

Documentation

Please, follow [this bug] for more insights.


Release Notes

OpenLDAP does not ship non-threaded version of libldap any more, and it is seamlessly replaced by the threaded libldap_r. No additional action from development should be required.