Submitting patches or diff's to the FreeRADIUS project ====================================================== For a person or company wishing to submit a change to the FreeRADIUS project, the process can sometimes be daunting if you're not familiar with "the system." This text is a collection of suggestions which can greatly increase the chances of your change being accepted. Creating and Sending Your Change -------------------------------- 1. "diff -u" Use "diff -u" or "diff -urN" to create patches. All changes to the source occur in the form of patches, as generated by diff(1). When creating your patch, make sure to create it in "unified diff" format, as supplied by the '-u' argument to diff(1). Patches should be based in the root source directory, not in any lower subdirectory. To create a patch for a single file, it is often sufficient to do: SRCTREE=/home/user/src/freeradiusd/ MYFILE=src/modules/rlm_foo/foo.c cd $SRCTREE cp $MYFILE $MYFILE.orig vi $MYFILE # make your change diff -u $MYFILE.orig $MYFILE > /tmp/patch To create a patch for multiple files, you should unpack a "vanilla", or unmodified source tree, and generate a diff against your own source tree. For example: MYSRC=/home/user/src/freeradiusd-feature/ gunzip freeradiusd-version.tar.gz tar xvf freeradiusd-version.tar diff -urN freeradiusd-version $MYSRC > ~/feature-version.patch 2. Describe your changes. Describe the technical detail of the change(s) your patch includes. Be as specific as possible. The WORST descriptions possible include things like "update file X", "bug fix for file X", or "this patch includes updates for subsystem X. Please apply." If your description starts to get long, that's a sign that you probably need to split up your patch. See #3, next. 3. Separate your changes. Separate each logical change into its own patch. For example, if your changes include both bug fixes and performance enhancements for a single module, separate those changes into two or more patches. On the other hand, if you make a single change to numerous files, group those changes into a single patch. Thus a single LOGICAL change is contained within a single patch. If one patch depends on another patch in order for a change to be complete, that is OK. Simply note "this patch depends on patch X" in your patch description. 4. Select e-mail destination. If you are on the developers mailing list, send the patch there. freeradius-devel@lists.freeradius.org Otherwise, send the patch to 'patches@freeradius.org' 5. No MIME, no links, no compression, no attachments. Just plain text. The developers need to be able to read and comment on the changes you are submitting. It is important for a developer to be able to "quote" your changes, using standard e-mail tools, so that they may comment on specific portions of your code. For this reason, all patches should be submitting e-mail "inline". Do not attach the patch as a MIME attachment, compressed or not. Many popular e-mail applications will not always transmit a MIME attachment as plain text, making it impossible to comment on your code. A MIME attachment also takes a bit more time to process, decreasing the likelihood of your MIME-attached change being accepted. Compressed patches are generally rejected outright. If the developer has to do additional work to read your patch, the odds are that it will be ignored completely. 6. E-mail size. When sending patches, always follow step #5. Large changes are not appropriate for mailing lists, and some maintainers. If your patch, exceeds 40Kb in size, it is preferred that you store your patch on an Internet-accessible server, and provide instead a URL (link) pointing to your patch. 7. Name the version of the server. It is important to note, either in the subject line or in the patch description, the server version to which this patch applies. 8. Don't get discouraged. Re-submit. After you have submitted your change, be patient and wait. If the patch is approved and applied, it will appear in the next version of the server. However, if your change doesn't appear in the next version of the server, there could be any number of reasons. It's YOUR job to narrow down those reasons, correct what was wrong, and submit your updated change. It is quite common a patch to be "dropped" without comment. That's the nature of the system. If your patch is dropped, it could be due to A style issue (see section 2, below), An e-mail formatting issue (see section item 5, above) A technical problem with your change Your patch got lost among other patches When in doubt, re-submit. Hints, Tips, and Tricks ----------------------- This section lists many of the common "rules" associated with code submitted to the project. There are always exceptions... but you must have a really good reason for doing so. 1. Read the Documentation and follow the CodingStyle The FreeRADIUS server has a common coding style. Use real tabs to indent. There is whitespace in variable assignments. (i = 1, NOT i=1). When in doubt, format your code to look the same as code already in the server. If your code deviates too much from the current style, it is likely to be rejected without further review, and without comment. 2. #ifdefs are ugly Code cluttered with ifdefs is difficult to read and maintain. Don't do it. Instead, put your ifdefs in a header, and conditionally define 'static inline' functions, or macros, which are used in the code. Let the compiler optimize away the "no-op" case. Simple example, of poor code:: #ifdef CONFIG_MY_FUNKINESS init_my_stuff(foo); #endif Cleaned-up example: (in header):: #ifndef CONFIG_MY_FUNKINESS static inline void init_my_stuff(char *foo) {} #endif (in the code itself):: init_my_stuff(dev); 3. 'static inline' is better than a macro Static inline functions are greatly preferred over macros. They provide type safety, have no length limitations, no formatting limitations, and under gcc they are as cheap as macros. Macros should only be used for cases where a static inline is clearly suboptimal [there a few, isolated cases of this in fast paths], or where it is impossible to use a static inline function [such as string-izing]. 'static inline' is preferred over 'static __inline__', 'extern inline', and 'extern __inline__'. 4. Don't over-design. Don't try to anticipate nebulous future cases which may or may not be useful: "Make it as simple as you can, and no simpler" Split up functionality as much as possible. If your code needs to do two unrelated things, write two functions. Mashing two kinds of work into one function makes the server difficult to debug and maintain. See the 'coding-methods.txt' document in this directory for further description of coding methods.