4 \section*{Bacula Developer Notes}
5 \label{_ChapterStart10}
6 \index{Bacula Developer Notes}
7 \index{Notes!Bacula Developer}
8 \addcontentsline{toc}{section}{Bacula Developer Notes}
12 \addcontentsline{toc}{subsection}{General}
14 This document is intended mostly for developers and describes the the general
15 framework of making Bacula source changes.
17 \subsubsection*{Contributions}
19 \addcontentsline{toc}{subsubsection}{Contributions}
21 Contributions from programmers are broken into two groups. The first are
22 contributions that are aids and not essential to Bacula. In general, these
23 will be scripts or will go into and examples or contributions directory.
24 For these kinds of non-essential contributions there is no obligation to do
25 a copyright assignment as described below. However, a copyright assignment
26 would still be appreciated.
28 The second class of contributions are those which will be integrated with
29 Bacula and become an essential part. Within this class of contributions, there
30 are two hurdles to surmount. One is getting your patch accepted, and two is
31 dealing with copyright issues. The following text describes some of the
32 requirements for such code.
34 \subsubsection*{Patches}
36 \addcontentsline{toc}{subsubsection}{Patches}
38 Subject to the copyright assignment described below, your patches should be
39 sent in {\bf diff -u} format relative to the current contents of the Source
40 Forge SVN, which is the easiest to understand and integrate.
41 Please be sure to use the Bacula indenting standard (see below).
42 If you have checked out the source with SVN, you can get a diff using:
45 svn diff > change.patch
48 If you plan on doing significant development work over a period of time,
49 after having your first patch reviewed and approved, you will be eligible
50 for having developer SVN access so that you can commit your changes
51 directly to the SVN repository. To do so, you will need a userid on Source
54 \subsubsection*{Copyrights}
56 \addcontentsline{toc}{subsubsection}{Copyrights}
58 To avoid future problems concerning changing licensing or
59 copyrights, all code contributions more than a hand full of lines
60 must be in the Public Domain or have the copyright transferred to
61 the Free Software Foundation Europe e.V. with a Fiduciary License
62 Agreement (FLA) as in the current code. Note, prior to
63 November 2004, the code was copyrighted by Kern Sibbald and John
64 Walker. After November 2004, the code was copyrighted by Kern
65 Sibbald, then on the 15th of November 2006, the copyright was
66 transferred to the Free Software Foundation Europe e.V.
68 Your name should be clearly indicated as the author of the code, and you
69 must be extremely careful not to violate any copyrights or use other
70 people's code without acknowledging it. The purpose of this requirement is
71 to avoid future copyright, patent, or intellectual property problems.
72 Please read the LICENSE agreement in the main source code
73 directory. When you sign the Fiduciary License Agreement (FLA)
74 and send it in, you are argeeing to the terms of that LICENSE
77 To understand the possible source of future problems, please
78 examine the difficulties Mozilla is (was?) having finding
79 previous contributors at \elink{
80 http://www.mozilla.org/MPL/missing.html}
81 {http://www.mozilla.org/MPL/missing.html}. The other important issue is to
82 avoid copyright, patent, or intellectual property violations as are currently
83 (May 2003) being claimed by SCO against IBM.
85 Although the copyright will be held by the Free Software
86 Foundation Europe e.V., each developer is expected to indicate
87 that he wrote and/or modified a particular module (or file) and
88 any other sources. The copyright assignment may seem a bit
89 unusual, but in reality, it is not. Most large projects require
92 If you have any doubts about this, please don't hesitate to ask. The
93 objective is to assure the long term servival of the Bacula project.
95 Items not needing a copyright assignment are: most small changes,
96 enhancements, or bug fixes of 5-10 lines of code, which amount to
97 less than 20% of any particular file.
99 \subsubsection*{Copyright Assignment -- Fiduciary License Agreement}
100 \index{Copyright Assignment}
101 \index{Assignment!Copyright}
102 \addcontentsline{toc}{subsubsection}{Copyright Assignment -- Fiduciary License Agreement}
104 Since this is not a commercial enterprise, and we prefer to believe in
105 everyone's good faith, previously developers could assign the copyright by
106 explicitly acknowledging that they do so in their first submission. This
107 was sufficient if the developer is independent, or an employee of a
108 not-for-profit organization or a university. However, in an effort to
109 ensure that the Bacula code is really clean, beginning in August 2006, all
110 previous and future developers with SVN access will be asked to submit a
111 copyright assignment (or Fiduciary License Agreement -- FLA),
112 which means you agree to the LICENSE in the main source
113 directory. It also means that you receive back the right to use
114 the code that you have submitted.
116 Any developer who wants to contribute and is employed by a company should
117 either list the employer as the owner of the code, or get
118 explicit permission from him to sign the copyright assignment.
119 This is because in many
120 countries, all work that an employee does whether on company time or in the
121 employee's free time is considered to be Intellectual Property of the
122 company. Obtaining official approval or an FLA from the company will avoid
123 misunderstandings between the employee, the company, and the Bacula
124 project. A good number of companies have already followed this procedure.
126 The Fiduciary License Agreement is posted on the Bacula web site at:
127 \elink{http://www.bacula.org/FLA-bacula.en.pdf}{http://www.bacula.org/FLA-bacula.en.pdf}
129 The instructions for filling out this agreement are also at:
130 \elink{http://www.bacula.org/?page=fsfe}{http://www.bacula.org/?page=fsfe}
132 It should be filled out, then sent to:
135 Free Software Foundation Europe
142 Please note that the above address is different from the officially
143 registered office mentioned in the document. When you send in such a
144 complete document, please notify me: kern at sibbald dot com.
148 \subsection*{The Development Cycle}
149 \index{Developement Cycle}
150 \index{Cycle!Developement}
151 \addcontentsline{toc}{subsubsection}{Development Cycle}
153 As I noted in the 1.38 ReleaseNotes, version 1.38 was different from prior
154 versions because it had a lot more contributions. I expect that this trend
155 will continue. As a consequence, I am going to modify how I normally do
156 development, and instead of making a list of all the features that I will
157 implement in the next version, I will personally sign up for one (maybe
158 two) projects at a time, and when they are complete, I will release a new
161 The difference is that I will have more time to review the new code that is
162 being contributed, and will be able to devote more time to a smaller number
163 of projects (1.38 had too many new features for me to handle correctly).
165 I expect that future release schedules will be much the same, and the
166 number of new features will also be much the same providing that the
167 contributions continue to come -- and they show no signs of let up :-)
169 \index{Feature Requests}
170 {\bf Feature Requests:} \\
171 In addition, I would like to "formalize" the feature requests a bit.
173 Instead of me maintaining an informal list of everything I run into
174 (kernstodo), I would like to maintain a "formal" list of projects. This
175 means that all new feature requests, including those recently discussed on
176 the email lists, must be formally submitted and approved.
178 Formal submission of feature requests will take two forms: \\
179 1. non-mandatory, but highly recommended is to discuss proposed new features
180 on the mailing list.\\
181 2. Formal submission of an Feature Request in a special format.
182 I'll give an example of this below, but you can also find it on the web
183 site under "Support -\gt{} Feature Requests". Since it takes a bit of time to
184 properly fill out a Feature Request form, you probably should check on the email list
187 Once I receive the Feature Request, I will either accept it, send it back
188 asking for clarification, send it to the email list asking for opinions, or
191 If it is accepted, it will go in the "projects" file (a simple ASCII file)
192 maintained in the main Bacula source directory.
194 {\bf Implementation of Feature Requests:}\\
195 Any qualified developer can sign up for a project. The project must have
196 an entry in the projects file, and the developer's name will appear in the
199 {\bf How Feature Requests are accepted:}\\
200 Acceptance of Feature Requests depends on several things: \\
201 1. feedback from users. If it is negative, the Feature Request will probably not be
203 2. the difficulty of the project. A project that is so
204 difficult that I cannot imagine finding someone to implement probably won't
206 3. whether or not the Feature Request fits within the
207 current stategy of Bacula (for example an Feature Request that requests changing the
208 tape to tar format would not be accepted, ...)
210 {\bf How Feature Requests are prioritized:}\\
211 Once an Feature Request is accepted, it needs to be implemented. If you
212 can find a developer for it, or one signs up for implementing it, then the
213 Feature Request becomes top priority (at least for that developer).
215 Between releases of Bacula, I will generally solicit Feature Request input
216 for the next version, and by way of this email, I suggest that you send
217 discuss and send in your Feature Requests for the next release. Please
218 verify that the Feature Request is not in the current list (attached to this email).
220 Once users have had several weeks to submit Feature Requests, I will
221 organize them, and request users to vote on them. This will allow fixing
222 prioritizing the Feature Requests. Having a priority is one thing, but
223 getting it implement is another thing -- I am hoping that the Bacula
224 community will take more responsibility for assuring the implementation of
225 accepted Feature Requests.
227 Feature Request format:
229 ============= Empty Feature Request form ===========
230 Item n: One line summary ...
232 Origin: Name and email of originator.
235 What: More detailed explanation ...
237 Why: Why it is important ...
239 Notes: Additional notes or features (omit if not used)
240 ============== End Feature Request form ==============
244 ============= Example Completed Feature Request form ===========
245 Item 1: Implement a Migration job type that will move the job
246 data from one device to another.
247 Origin: Sponsored by Riege Sofware International GmbH. Contact:
248 Daniel Holtkamp <holtkamp at riege dot com>
249 Date: 28 October 2005
250 Status: Partially coded in 1.37 -- much more to do. Assigned to
253 What: The ability to copy, move, or archive data that is on a
254 device to another device is very important.
256 Why: An ISP might want to backup to disk, but after 30 days
257 migrate the data to tape backup and delete it from
258 disk. Bacula should be able to handle this
259 automatically. It needs to know what was put where,
260 and when, and what to migrate -- it is a bit like
261 retention periods. Doing so would allow space to be
262 freed up for current backups while maintaining older
265 Notes: Migration could be triggered by:
269 Highwater size (keep total size)
271 =================================================
275 \subsubsection*{SVN Usage}
277 \addcontentsline{toc}{subsubsection}{SVN Usage}
279 Please note that if you are familar with CVS, SVN is very
280 similar (and better), but there can be a few surprising
283 The *entire* Bacula SourceForge.net Subversion repository can be
284 checked out through SVN with the following command:
287 svn checkout https://bacula.svn.sourceforge.net/svnroot/bacula bacula
290 With the above command, you will get everything, which is a very large
312 If you only want the current source code, you could use:
315 svn checkout https://bacula.svn.sourceforge.net/svnroot/bacula/trunk/bacula bacula
319 To view what is in the svn, point your browser at the following URL:
320 http://bacula.svn.sourceforge.net/viewvc/bacula/
322 Many of the Subversion (svn) commands are almost identical to those that
323 you have used for cvs, but some (such as a checkout) can have surprising
324 results, so you should take a careful look at the documentation.
326 Robert has kindly provided the following documentation on the new
327 svn repository and how to use it:
329 Here is the list of branches:
346 Release-1.1 Release-1.19 Release-1.19a Release-1.19b
347 Release-1.20 Release-1.21 Release-1.22 Release-1.23
348 Release-1.23a Release-1.24 Release-1.25 Release-1.25a
349 Release-1.26 Release-1.27 Release-1.27a Release-1.27b
350 Release-1.27c Release-1.28 Release-1.29 Release-1.30
351 Release-1.31 Release-1.31a Release-1.32 Release-1.32a
352 Release-1.32b Release-1.32c Release-1.32d Release-1.32e
353 Release-1.32f Release-1.32f-2 Release-1.32f-3 Release-1.32f-4
354 Release-1.32f-5 Release-1.34.0 Release-1.34.1 Release-1.34.3
355 Release-1.34.4 Release-1.34.5 Release-1.34.6 Release-1.35.1
356 Release-1.35.2 Release-1.35.3 Release-1.35.6 Release-1.35.7
357 Release-1.35.8 Release-1.36.0 Release-1.36.1 Release-1.36.2
358 Release-1.36.3 Release-1.38.0 Release-1.38.1 Release-1.38.10
359 Release-1.38.11 Release-1.38.2 Release-1.38.3 Release-1.38.4
360 Release-1.38.5 Release-1.38.6 Release-1.38.7 Release-1.38.8
361 Release-1.38.9 Release-1.8.1 Release-1.8.2 Release-1.8.3
362 Release-1.8.4 Release-1.8.5 Release-1.8.6 Release-2.0.0
363 Release-2.0.1 Release-2.0.2
366 Here is a list of commands to get you started. The recommended book is
367 "Version Control with Subversion", by Ben Collins-Sussmann,
368 Brian W. Fitzpatrick, and Michael Pilato, O'Reilly. The book is
369 Open Source, so it is also available on line at:
372 http://svnbook.red-bean.com
375 Get a list of commands
381 Get a help with a command
387 Checkout the HEAD revision of all modules from the project into the
391 svn co https://bacula.svn.sourceforge.net/svnroot/bacula/trunk bacula.new
394 Checkout the HEAD revision of the bacula module into the bacula subdirectory
397 svn checkout https://bacula.svn.sourceforge.net/svnroot/bacula/trunk/bacula
400 See which files have changed in the working copy
406 See which files are out of date
412 Add a new file file.c
418 Create a new directory
424 Delete an obsolete file
433 svn move file.c newfile.c
436 Move a file to a new location
439 svn move file.c ../newdir/file.c
442 Copy a file retaining the original history in the new file
445 svn copy file.c newfile.c
448 Update the working copy with the outstanding changes
454 Compare working copy with the repository
460 Commit the changes in the local working copy
466 Specify which files are ignored in the current directory
469 svn propedit svn:ignore .
472 Mark a file to be executable
475 svn propset svn:executable '*' prog.sh
478 Unmark a file as executable
481 svn propdel svn:executable prog.sh
484 List a file's properties
490 Create a branch for a new version
493 svn copy https://bacula.svn.sourceforge.net/svnroot/bacula/trunk \
494 https://bacula.svn.sourceforge.net/svnroot/bacula/branches/Branch-2.1
497 Tag a version for a new release
500 svn copy https://bacula.svn.sourceforge.net/svnroot/bacula/branches/Branch-2.1 \
501 https://bacula.svn.sourceforge.net/svnroot/bacula/branches/Release-2.1
505 Let's say you are working in the directory scripts. You would then do:
512 when you are happy with your changes, you can do the following:
515 cd bacula (to your top level directory)
516 svn diff my-changes.patch
519 When the command is done, you can look in the file my-changes.patch
520 and you will see all the changes you have made to your copy of the
521 repository. Make sure that you understand all the changes that
522 it reports before proceeding. If you modified files that you do
523 do not want to commit to the main repository, you can simply delete
524 them from your local directory, and they will be restored from the
525 repository with the "svn update" that is shown below. Normally, you
526 should not find changes to files that you do not want to commit, and
527 if you find yourself in that position a lot, you are probably doing
530 Let's assume that now you want to commit your changes to the main
540 When you do this, it will pull any changes made by other developers into
541 your local copy of the repository, and it will check for conflicts. If there
542 are any, it will tell you, and you will need to resolve them. The problems
543 of resolving conflicts are a bit more than this document can cover, but
544 you can examine the files it claims have conflicts and look for \lt{}\lt{}\lt{}\lt{}
545 or look in the .rej files that it creates. If you have problems, just ask
546 on the developer's list.
548 Note, doing the above "svn update" is not absolutely necessary. There are
549 times when you may be working on code and you want to commit it, but you
550 explicitly do not want to move up to the latest version of the code in
551 the SVN. If that is the case, you can simply skip the "svn update" and
552 do the commit shown below. If the commit fails because of a conflict, it
553 will tell you, and you must resolve the conflict before it will permit
554 you to do the commit.
556 Once your local copy of the repository has been updated, you can now
560 svn commit -m "Some comment about what you changed"
563 or if you really only want to commit a single file, you can
567 svn commit -m "comment" scripts/file-I-edited
570 Note, if you have done a build in your directory, or you have added
571 other new files, the commit will update only the files that are
572 actually in the repository. For example, none of the object files
573 are stored in the repository, so when you do a commit, those object
574 files will simply be ignored.
576 If you want to add new files or remove files from the main SVN
577 repository, and you are not experienced with SVN, please ask Kern
578 to do it. If you follow the simple steps above, it is unlikely that
579 you will do any damage to the repository, and if you do, it is always
580 possible for us to recover, but it can be painful.
582 If you are only working in one subdirectory of say the bacula project,
583 for example, the scripts directory, you can do your commit from
584 that subdirectory, and only the changes in that directory and all its
585 subdirectories will be committed. This can be helpful for translators.
586 If you are doing a French translation, you will be working in
587 docs/manual-fr, and if you are always cd'ed into that directory when
588 doing your commits, your commit will effect only that directory. As
589 long as you are careful only to change files that you want changed,
590 you have little to worry about.
592 \subsection*{Subversion Resources}
593 \link{Subversion (svn) Resources}
594 \addcontentsline{toc}{subsection}{Subversion Resources}
599 Total CVS Files: 3286
600 Total CVS Revisions: 28924
601 Total Unique Tags: 63
602 Total Unique Branches: 11
603 CVS Repos Size in KB: 232421
604 Total SVN Commits: 4116
605 First Revision Date: Tue Apr 23 12:42:57 2002
606 Last Revision Date: Tue Feb 6 06:37:57 2007
609 The new Subversion repository size on Robert's machine:
616 190M bacula-tst/db/revs
617 17M bacula-tst/db/revprops
618 4.0K bacula-tst/db/transactions
625 \elink{http://subversion.tigris.org}{http://subversion.tigris.org}
628 \elink{http://svnbook.red-bean.com}{http://svnbook.red-bean.com}
631 \elink{http://subversion.tigris.org/project_packages.html}{http://subversion.tigris.org/project_packages.html}
633 (For Windows users the TortoiseSVN package is awesome)
636 \elink{http://rapidsvn.tigris.org/}{http://rapidsvn.tigris.org/}
640 \subsection*{Developing Bacula}
641 \index{Developing Bacula}
642 \index{Bacula!Developing}
643 \addcontentsline{toc}{subsubsection}{Developing Bacula}
645 Typically the simplest way to develop Bacula is to open one xterm window
646 pointing to the source directory you wish to update; a second xterm window at
647 the top source directory level, and a third xterm window at the bacula
648 directory \lt{}top\gt{}/src/bacula. After making source changes in one of the
649 directories, in the top source directory xterm, build the source, and start
650 the daemons by entering:
654 ./startit then in the enter:
658 ./gnome-console to start the Console program. Enter any commands for testing.
659 For example: run kernsverify full.
661 Note, the instructions here to use {\bf ./startit} are different from using a
662 production system where the administrator starts Bacula by entering {\bf
663 ./bacula start}. This difference allows a development version of {\bf Bacula}
664 to be run on a computer at the same time that a production system is running.
665 The {\bf ./startit} strip starts {\bf Bacula} using a different set of
666 configuration files, and thus permits avoiding conflicts with any production
669 To make additional source changes, exit from the Console program, and in the
670 top source directory, stop the daemons by entering:
672 ./stopit then repeat the process.
674 \subsubsection*{Debugging}
676 \addcontentsline{toc}{subsubsection}{Debugging}
678 Probably the first thing to do is to turn on debug output.
680 A good place to start is with a debug level of 20 as in {\bf ./startit -d20}.
681 The startit command starts all the daemons with the same debug level.
682 Alternatively, you can start the appropriate daemon with the debug level you
683 want. If you really need more info, a debug level of 60 is not bad, and for
684 just about everything a level of 200.
686 \subsubsection*{Using a Debugger}
687 \index{Using a Debugger}
688 \index{Debugger!Using a}
689 \addcontentsline{toc}{subsubsection}{Using a Debugger}
691 If you have a serious problem such as a segmentation fault, it can usually be
692 found quickly using a good multiple thread debugger such as {\bf gdb}. For
693 example, suppose you get a segmentation violation in {\bf bacula-dir}. You
694 might use the following to find the problem:
696 \lt{}start the Storage and File daemons\gt{}
699 run -f -s -c ./dird.conf
700 \lt{}it dies with a segmentation fault\gt{}
702 The {\bf -f} option is specified on the {\bf run} command to inhibit {\bf
703 dird} from going into the background. You may also want to add the {\bf -s}
704 option to the run command to disable signals which can potentially interfere
707 As an alternative to using the debugger, each {\bf Bacula} daemon has a built
708 in back trace feature when a serious error is encountered. It calls the
709 debugger on itself, produces a back trace, and emails the report to the
710 developer. For more details on this, please see the chapter in the main Bacula
711 manual entitled ``What To Do When Bacula Crashes (Kaboom)''.
713 \subsubsection*{Memory Leaks}
716 \addcontentsline{toc}{subsubsection}{Memory Leaks}
718 Because Bacula runs routinely and unattended on client and server machines, it
719 may run for a long time. As a consequence, from the very beginning, Bacula
720 uses SmartAlloc to ensure that there are no memory leaks. To make detection of
721 memory leaks effective, all Bacula code that dynamically allocates memory MUST
722 have a way to release it. In general when the memory is no longer needed, it
723 should be immediately released, but in some cases, the memory will be held
724 during the entire time that Bacula is executing. In that case, there MUST be a
725 routine that can be called at termination time that releases the memory. In
726 this way, we will be able to detect memory leaks. Be sure to immediately
727 correct any and all memory leaks that are printed at the termination of the
730 \subsubsection*{Special Files}
731 \index{Files!Special}
732 \index{Special Files}
733 \addcontentsline{toc}{subsubsection}{Special Files}
735 Kern uses files named 1, 2, ... 9 with any extension as scratch files. Thus
736 any files with these names are subject to being rudely deleted at any time.
738 \subsubsection*{When Implementing Incomplete Code}
739 \index{Code!When Implementing Incomplete}
740 \index{When Implementing Incomplete Code}
741 \addcontentsline{toc}{subsubsection}{When Implementing Incomplete Code}
743 Please identify all incomplete code with a comment that contains
749 where there are three asterisks (*) before and after the word
750 FIXME (in capitals) and no intervening spaces. This is important as it allows
751 new programmers to easily recognize where things are partially implemented.
753 \subsubsection*{Bacula Source File Structure}
754 \index{Structure!Bacula Source File}
755 \index{Bacula Source File Structure}
756 \addcontentsline{toc}{subsubsection}{Bacula Source File Structure}
758 The distribution generally comes as a tar file of the form {\bf
759 bacula.x.y.z.tar.gz} where x, y, and z are the version, release, and update
760 numbers respectively.
762 Once you detar this file, you will have a directory structure as follows:
769 |- mtx (autochanger control program + tape drive info)
770 |- sqlite (SQLite database program)
774 |- pthreads (Native win32 pthreads library -- dll)
775 |- zlib (Native win32 zlib library)
776 |- wx (wxWidgets source code)
779 |- bacula (main source directory containing configuration
780 | and installation files)
781 |- autoconf (automatic configuration files, not normally used
783 |- intl (programs used to translate)
784 |- platforms (OS specific installation files)
785 |- redhat (Red Hat installation)
786 |- solaris (Sun installation)
787 |- freebsd (FreeBSD installation)
788 |- irix (Irix installation -- not tested)
789 |- unknown (Default if system not identified)
790 |- po (translations of source strings)
791 |- src (source directory; contains global header files)
792 |- cats (SQL catalog database interface directory)
793 |- console (bacula user agent directory)
794 |- dird (Director daemon)
795 |- filed (Unix File daemon)
796 |- win32 (Win32 files to make bacula-fd be a service)
797 |- findlib (Unix file find library for File daemon)
798 |- gnome-console (GNOME version of console program)
799 |- lib (General Bacula library)
800 |- stored (Storage daemon)
801 |- tconsole (Tcl/tk console program -- not yet working)
802 |- testprogs (test programs -- normally only in Kern's tree)
803 |- tools (Various tool programs)
804 |- win32 (Native Win32 File daemon)
805 |- baculafd (Visual Studio project file)
806 |- compat (compatibility interface library)
807 |- filed (links to src/filed)
808 |- findlib (links to src/findlib)
809 |- lib (links to src/lib)
810 |- console (beginning of native console program)
811 |- wx-console (wxWidget console Win32 specific parts)
812 |- wx-console (wxWidgets console main source program)
815 |- regress (Regression scripts)
816 |- bin (temporary directory to hold Bacula installed binaries)
817 |- build (temporary directory to hold Bacula source)
818 |- scripts (scripts and .conf files)
819 |- tests (test scripts)
820 |- tmp (temporary directory for temp files)
821 |- working (temporary working directory for Bacula daemons)
824 |- docs (documentation directory)
825 |- developers (Developer's guide)
826 |- home-page (Bacula's home page source)
827 |- manual (html document directory)
828 |- manual-fr (French translation)
829 |- manual-de (German translation)
830 |- techlogs (Technical development notes);
833 |- rescue (Bacula rescue CDROM)
834 |- linux (Linux rescue CDROM)
835 |- cdrom (Linux rescue CDROM code)
837 |- solaris (Solaris rescue -- incomplete)
838 |- freebsd (FreeBSD rescue -- incomplete)
841 |- gui (Bacula GUI projects)
842 |- bacula-web (Bacula web php management code)
843 |- bimagemgr (Web application for burning CDROMs)
849 \subsubsection*{Header Files}
852 \addcontentsline{toc}{subsubsection}{Header Files}
854 Please carefully follow the scheme defined below as it permits in general only
855 two header file includes per C file, and thus vastly simplifies programming.
856 With a large complex project like Bacula, it isn't always easy to ensure that
857 the right headers are invoked in the right order (there are a few kludges to
858 make this happen -- i.e. in a few include files because of the chicken and egg
859 problem, certain references to typedefs had to be replaced with {\bf void} ).
861 Every file should include {\bf bacula.h}. It pulls in just about everything,
862 with very few exceptions. If you have system dependent ifdefing, please do it
863 in {\bf baconfig.h}. The version number and date are kept in {\bf version.h}.
865 Each of the subdirectories (console, cats, dird, filed, findlib, lib, stored,
866 ...) contains a single directory dependent include file generally the name of
867 the directory, which should be included just after the include of {\bf
868 bacula.h}. This file (for example, for the dird directory, it is {\bf dird.h})
869 contains either definitions of things generally needed in this directory, or
870 it includes the appropriate header files. It always includes {\bf protos.h}.
873 Each subdirectory contains a header file named {\bf protos.h}, which contains
874 the prototypes for subroutines exported by files in that directory. {\bf
875 protos.h} is always included by the main directory dependent include file.
877 \subsubsection*{Programming Standards}
878 \index{Standards!Programming}
879 \index{Programming Standards}
880 \addcontentsline{toc}{subsubsection}{Programming Standards}
882 For the most part, all code should be written in C unless there is a burning
883 reason to use C++, and then only the simplest C++ constructs will be used.
884 Note, Bacula is slowly evolving to use more and more C++.
886 Code should have some documentation -- not a lot, but enough so that I can
887 understand it. Look at the current code, and you will see that I document more
888 than most, but am definitely not a fanatic.
890 I prefer simple linear code where possible. Gotos are strongly discouraged
891 except for handling an error to either bail out or to retry some code, and
892 such use of gotos can vastly simplify the program.
894 Remember this is a C program that is migrating to a {\bf tiny} subset of C++,
895 so be conservative in your use of C++ features.
897 \subsubsection*{Do Not Use}
900 \addcontentsline{toc}{subsubsection}{Do Not Use}
903 \item STL -- it is totally incomprehensible.
906 \subsubsection*{Avoid if Possible}
907 \index{Possible!Avoid if}
908 \index{Avoid if Possible}
909 \addcontentsline{toc}{subsubsection}{Avoid if Possible}
912 \item Using {\bf void *} because this generally means that one must
913 using casting, and in C++ casting is rather ugly. It is OK to use
914 void * to pass structure address where the structure is not known
915 to the routines accepting the packet (typically callback routines).
916 However, declaring "void *buf" is a bad idea. Please use the
917 correct types whenever possible.
918 \item Using undefined storage specifications such as (short, int, long,
919 long long, size_t ...). The problem with all these is that the number of bytes
920 they allocate depends on the compiler and the system. Instead use
921 Bacula's types (int8_t, uint8_t, int32_t, uint32_t, int64_t, and
922 uint64_t). This guarantees that the variables are given exactly the
923 size you want. Please try at all possible to avoid using size_t ssize_t
924 and the such. They are very system dependent. However, some system
925 routines may need them, so their use is often unavoidable.
926 \item Returning a malloc'ed buffer from a subroutine -- someone will forget
928 \item Using reference variables -- it allows subroutines to create side
929 effects. Reference variables are OK, if you are sure the variable
930 *always* exists, and you are sure you can handle the side effects of
931 a subroutine changing the "pointer".
932 \item Heap allocation (malloc) unless needed -- it is expensive.
933 \item Templates -- they can create portability problems.
934 \item Fancy or tricky C or C++ code, unless you give a good explanation of
936 \item Too much inheritance -- it can complicate the code, and make reading it
937 difficult (unless you are in love with colons)
940 \subsubsection*{Do Use Whenever Possible}
941 \index{Possible!Do Use Whenever}
942 \index{Do Use Whenever Possible}
943 \addcontentsline{toc}{subsubsection}{Do Use Whenever Possible}
946 \item Locking and unlocking within a single subroutine.
947 \item Malloc and free within a single subroutine.
948 \item Comments and global explanations on what your code or algorithm does.
951 \subsubsection*{Indenting Standards}
952 \index{Standards!Indenting}
953 \index{Indenting Standards}
954 \addcontentsline{toc}{subsubsection}{Indenting Standards}
956 I cannot stand code indented 8 columns at a time. This makes the code
957 unreadable. Even 4 at a time uses a lot of space, so I have adopted indenting
958 3 spaces at every level. Note, indention is the visual appearance of the
959 source on the page, while tabbing is replacing a series of up to 8 spaces from
962 The closest set of parameters for the Linux {\bf indent} program that will
963 produce reasonably indented code are:
967 -nbad -bap -bbo -nbc -br -brs -c36 -cd36 -ncdb -ce -ci3 -cli0
968 -cp36 -d0 -di1 -ndj -nfc1 -nfca -hnl -i3 -ip0 -l85 -lp -npcs
969 -nprs -npsl -saf -sai -saw -nsob -nss -nbc -ncs -nbfda
973 You can put the above in your .indent.pro file, and then just invoke indent on
974 your file. However, be warned. This does not produce perfect indenting, and it
975 will mess up C++ class statements pretty badly.
977 Braces are required in all if statements (missing in some very old code). To
978 avoid generating too many lines, the first brace appears on the first line
979 (e.g. of an if), and the closing brace is on a line by itself. E.g.
989 Just follow the convention in the code. Originally I indented case clauses
990 under a switch(), but now I prefer non-indented cases.
1007 Avoid using // style comments except for temporary code or turning off debug
1008 code. Standard C comments are preferred (this also keeps the code closer to
1011 Attempt to keep all lines less than 85 characters long so that the whole line
1012 of code is readable at one time. This is not a rigid requirement.
1014 Always put a brief description at the top of any new file created describing
1015 what it does and including your name and the date it was first written. Please
1016 don't forget any Copyrights and acknowledgments if it isn't 100\% your code.
1017 Also, include the Bacula copyright notice that is in {\bf src/c}.
1019 In general you should have two includes at the top of the an include for the
1020 particular directory the code is in, for includes are needed, but this should
1023 In general (except for self-contained packages), prototypes should all be put
1024 in {\bf protos.h} in each directory.
1026 Always put space around assignment and comparison operators.
1037 but your can compress things in a {\bf for} statement:
1041 for (i=0; i < del.num_ids; i++) {
1046 Don't overuse the inline if (?:). A full {\bf if} is preferred, except in a
1047 print statement, e.g.:
1051 if (ua->verbose \&& del.num_del != 0) {
1052 bsendmsg(ua, _("Pruned %d %s on Volume %s from catalog.\n"), del.num_del,
1053 del.num_del == 1 ? "Job" : "Jobs", mr->VolumeName);
1058 Leave a certain amount of debug code (Dmsg) in code you submit, so that future
1059 problems can be identified. This is particularly true for complicated code
1060 likely to break. However, try to keep the debug code to a minimum to avoid
1061 bloating the program and above all to keep the code readable.
1063 Please keep the same style in all new code you develop. If you include code
1064 previously written, you have the option of leaving it with the old indenting
1065 or re-indenting it. If the old code is indented with 8 spaces, then please
1066 re-indent it to Bacula standards.
1068 If you are using {\bf vim}, simply set your tabstop to 8 and your shiftwidth
1071 \subsubsection*{Tabbing}
1073 \addcontentsline{toc}{subsubsection}{Tabbing}
1075 Tabbing (inserting the tab character in place of spaces) is as normal on all
1076 Unix systems -- a tab is converted space up to the next column multiple of 8.
1077 My editor converts strings of spaces to tabs automatically -- this results in
1078 significant compression of the files. Thus, you can remove tabs by replacing
1079 them with spaces if you wish. Please don't confuse tabbing (use of tab
1080 characters) with indenting (visual alignment of the code).
1082 \subsubsection*{Don'ts}
1084 \addcontentsline{toc}{subsubsection}{Don'ts}
1099 They are system dependent and un-safe. These should be replaced by the Bacula
1104 char *bstrncpy(char *dest, char *source, int dest_size);
1105 char *bstrncat(char *dest, char *source, int dest_size);
1106 int bsnprintf(char *buf, int32_t buf_len, const char *fmt, ...);
1107 int bvsnprintf(char *str, int32_t size, const char *format, va_list ap);
1111 See src/lib/bsys.c for more details on these routines.
1113 Don't use the {\bf \%lld} or the {\bf \%q} printf format editing types to edit
1114 64 bit integers -- they are not portable. Instead, use {\bf \%s} with {\bf
1115 edit\_uint64()}. For example:
1120 uint64_t num = something;
1122 bsnprintf(buf, sizeof(buf), "Num=%s\n", edit_uint64(num, ed1));
1126 The edit buffer {\bf ed1} must be at least 27 bytes long to avoid overflow.
1127 See src/lib/edit.c for more details. If you look at the code, don't start
1128 screaming that I use {\bf lld}. I actually use subtle trick taught to me by
1129 John Walker. The {\bf lld} that appears in the editing routine is actually
1130 {\bf \#define} to a what is needed on your OS (usually ``lld'' or ``q'') and
1131 is defined in autoconf/configure.in for each OS. C string concatenation causes
1132 the appropriate string to be concatenated to the ``\%''.
1134 Also please don't use the STL or Templates or any complicated C++ code.
1136 \subsubsection*{Message Classes}
1137 \index{Classes!Message}
1138 \index{Message Classes}
1139 \addcontentsline{toc}{subsubsection}{Message Classes}
1141 Currently, there are five classes of messages: Debug, Error, Job, Memory,
1144 \subsubsection*{Debug Messages}
1145 \index{Messages!Debug}
1146 \index{Debug Messages}
1147 \addcontentsline{toc}{subsubsection}{Debug Messages}
1149 Debug messages are designed to be turned on at a specified debug level and are
1150 always sent to STDOUT. There are designed to only be used in the development
1151 debug process. They are coded as:
1153 DmsgN(level, message, arg1, ...) where the N is a number indicating how many
1154 arguments are to be substituted into the message (i.e. it is a count of the
1155 number arguments you have in your message -- generally the number of percent
1156 signs (\%)). {\bf level} is the debug level at which you wish the message to
1157 be printed. message is the debug message to be printed, and arg1, ... are the
1158 arguments to be substituted. Since not all compilers support \#defines with
1159 varargs, you must explicitly specify how many arguments you have.
1161 When the debug message is printed, it will automatically be prefixed by the
1162 name of the daemon which is running, the filename where the Dmsg is, and the
1163 line number within the file.
1165 Some actual examples are:
1167 Dmsg2(20, ``MD5len=\%d MD5=\%s\textbackslash{}n'', strlen(buf), buf);
1169 Dmsg1(9, ``Created client \%s record\textbackslash{}n'', client->hdr.name);
1171 \subsubsection*{Error Messages}
1172 \index{Messages!Error}
1173 \index{Error Messages}
1174 \addcontentsline{toc}{subsubsection}{Error Messages}
1176 Error messages are messages that are related to the daemon as a whole rather
1177 than a particular job. For example, an out of memory condition my generate an
1178 error message. They should be very rarely needed. In general, you should be
1179 using Job and Job Queued messages (Jmsg and Qmsg). They are coded as:
1181 EmsgN(error-code, level, message, arg1, ...) As with debug messages, you must
1182 explicitly code the of arguments to be substituted in the message. error-code
1183 indicates the severity or class of error, and it may be one of the following:
1185 \addcontentsline{lot}{table}{Message Error Code Classes}
1186 \begin{longtable}{lp{3in}}
1187 {{\bf M\_ABORT} } & {Causes the daemon to immediately abort. This should be
1188 used only in extreme cases. It attempts to produce a traceback. } \\
1189 {{\bf M\_ERROR\_TERM} } & {Causes the daemon to immediately terminate. This
1190 should be used only in extreme cases. It does not produce a traceback. } \\
1191 {{\bf M\_FATAL} } & {Causes the daemon to terminate the current job, but the
1192 daemon keeps running } \\
1193 {{\bf M\_ERROR} } & {Reports the error. The daemon and the job continue
1195 {{\bf M\_WARNING} } & {Reports an warning message. The daemon and the job
1196 continue running } \\
1197 {{\bf M\_INFO} } & {Reports an informational message.}
1201 There are other error message classes, but they are in a state of being
1202 redesigned or deprecated, so please do not use them. Some actual examples are:
1205 Emsg1(M\_ABORT, 0, ``Cannot create message thread: \%s\textbackslash{}n'',
1208 Emsg3(M\_WARNING, 0, ``Connect to File daemon \%s at \%s:\%d failed. Retrying
1209 ...\textbackslash{}n'', client-\gt{}hdr.name, client-\gt{}address,
1212 Emsg3(M\_FATAL, 0, ``bdird\lt{}filed: bad response from Filed to \%s command:
1213 \%d \%s\textbackslash{}n'', cmd, n, strerror(errno));
1215 \subsubsection*{Job Messages}
1216 \index{Job Messages}
1217 \index{Messages!Job}
1218 \addcontentsline{toc}{subsubsection}{Job Messages}
1220 Job messages are messages that pertain to a particular job such as a file that
1221 could not be saved, or the number of files and bytes that were saved. They
1224 Jmsg(jcr, M\_FATAL, 0, "Text of message");
1226 A Jmsg with M\_FATAL will fail the job. The Jmsg() takes varargs so can
1227 have any number of arguments for substituted in a printf like format.
1228 Output from the Jmsg() will go to the Job report.
1230 If the Jmsg is followed with a number such as Jmsg1(...), the number
1231 indicates the number of arguments to be substituted (varargs is not
1232 standard for \#defines), and what is more important is that the file and
1233 line number will be prefixed to the message. This permits a sort of debug
1236 \subsubsection*{Queued Job Messages}
1237 \index{Queued Job Messages}
1238 \index{Messages!Job}
1239 \addcontentsline{toc}{subsubsection}{Queued Job Messages}
1240 Queued Job messages are similar to Jmsg()s except that the message is
1241 Queued rather than immediately dispatched. This is necessary within the
1242 network subroutines and in the message editing routines. This is to prevent
1243 recursive loops, and to ensure that messages can be delivered even in the
1244 event of a network error.
1247 \subsubsection*{Memory Messages}
1248 \index{Messages!Memory}
1249 \index{Memory Messages}
1250 \addcontentsline{toc}{subsubsection}{Memory Messages}
1252 Memory messages are messages that are edited into a memory buffer. Generally
1253 they are used in low level routines such as the low level device file dev.c in
1254 the Storage daemon or in the low level Catalog routines. These routines do not
1255 generally have access to the Job Control Record and so they return error
1256 messages reformatted in a memory buffer. Mmsg() is the way to do this.