logging: Avoid memcpy from stack to msgb in _file_output()

For file and stderr output, the existing code always generates
the log string on a stack buffer, and then (in case of non-blocking
write via write_queue) copies it over to a msgb.

Let's optimize this by turning _file_output() into a raw_output
callback which first allocates the msgb and then format-prints
directly to that msgb instaed of stack + memcpy.

This has the disadvantage that we don't know how long the buffer
has to be in order to print the entire string to it.  As a result
we always have to allocate a 4k-sized buffer (plus msgb overhead).

The write_queue length for log file output has been decreased from
1024 entries to 156 entries in order to stay within the same
memory requirements for each log target memory pool (about 648 kBytes).

Related: OS#4311
Change-Id: I0d10b0199576d2e7ff6421a6dba19ae5ffafd946
1 file changed
tree: 6c8ab3a4912a5f3566c4f1ce12b01fae213f50b1
  1. contrib/
  2. debian/
  3. doc/
  4. include/
  5. m4/
  6. src/
  7. tapset/
  8. tests/
  9. utils/
  10. .gitignore
  11. .gitreview
  12. .mailmap
  13. configure.ac
  14. COPYING
  15. Doxyfile.codec.in
  16. Doxyfile.coding.in
  17. Doxyfile.core.in
  18. Doxyfile.ctrl.in
  19. Doxyfile.gb.in
  20. Doxyfile.gsm.in
  21. Doxyfile.vty.in
  22. git-version-gen
  23. libosmocodec.pc.in
  24. libosmocoding.pc.in
  25. libosmocore.pc.in
  26. libosmoctrl.pc.in
  27. libosmogb.pc.in
  28. libosmogsm.pc.in
  29. libosmosim.pc.in
  30. libosmousb.pc.in
  31. libosmovty.pc.in
  32. Makefile.am
  33. osmo-release.mk
  34. osmo-release.sh
  35. README.md
  36. TODO-RELEASE
README.md

libosmocore - set of Osmocom core libraries

This repository contains a set of C-language libraries that form the core infrastructure of many Osmocom Open Source Mobile Communications projects.

Historically, a lot of this code was developed as part of the OpenBSC project, but which are of a more generic nature and thus useful to (at least) other programs that we develop in the sphere of Free Software / Open Source mobile communications.

There is no clear scope of it. We simply move all shared code between the various Osmocom projects in this library to avoid code duplication.

The libosmocore.git repository build multiple libraries:

  • libosmocore contains some general-purpose functions like select-loop abstraction, message buffers, timers, linked lists
  • libosmovty contains routines related to the interactive command-line interface called VTY
  • libosmogsm contains definitions and helper code related to GSM protocols
  • libosmoctrl contains a shared implementation of the Osmocom control interface
  • libosmogb contains an implementation of the Gb interface with its NS/BSSGP protocols
  • libosmocodec contains an implementation of GSM voice codecs
  • libosmocoding contains an implementation of GSM channel coding
  • libosmosim contains infrastructure to interface SIM/UICC/USIM cards

Homepage

The official homepage of the project is https://osmocom.org/projects/libosmocore/wiki/Libosmocore

GIT Repository

You can clone from the official libosmocore.git repository using

git clone git://git.osmocom.org/libosmocore.git

There is a cgit interface at https://git.osmocom.org/libosmocore/

Documentation

Doxygen-generated API documentation is generated during the build process, but also available online for each of the sub-libraries at https://ftp.osmocom.org/api/latest/libosmocore/

Mailing List

Discussions related to libosmocore are happening on the openbsc@lists.osmocom.org mailing list, please see https://lists.osmocom.org/mailman/listinfo/openbsc for subscription options and the list archive.

Please observe the Osmocom Mailing List Rules when posting.

Contributing

Our coding standards are described at https://osmocom.org/projects/cellular-infrastructure/wiki/Coding_standards

We us a gerrit based patch submission/review process for managing contributions. Please see https://osmocom.org/projects/cellular-infrastructure/wiki/Gerrit for more details

The current patch queue for libosmocore can be seen at https://gerrit.osmocom.org/#/q/project:libosmocore+status:open