Re: [libvirt] [PATCH] Document preferred naming conventions

Daniel P. Berrange <berrange(a)redhat.com&gt; [2017-03-03, 10:50AM +0100]: > This documents the preferred conventions for naming files, > structs, enums, typedefs and functions. > > Signed-off-by: Daniel P. Berrange <berrange(a)redhat.com&gt; > --- > HACKING | 71 ++++++++++++++++++++++++++++++++++++++++++++ > docs/hacking.html.in | 83 ++++++++++++++++++++++++++++++++++++++++++++++++++++ > docs/hacking2.xsl | 4 +++ > 3 files changed, 158 insertions(+) > > diff --git a/HACKING b/HACKING > index fff003b..16be5cf 100644 > --- a/HACKING > +++ b/HACKING > @@ -239,6 +239,77 @@ on the subject, on Richard Jones' guide to working with open source projects > <http://people.redhat.com/rjones/how-to-supply-code-to-open-source-project...;. > > > +Naming conventions > +================== > +When reading libvirt code, a number of different naming conventions will be > +evident due to various changes in thinking over the course of the project's > +lifetime. The conventions documented below should be followed when creating > +any entirely new files in libvirt. When working on existing files, while it is > +desirable to apply these conventions, keeping a consistent style with existing > +code in that particular file is generally more important. The overall guiding > +rule is that every file, enum, struct, function, and typedef name must have a > +'vir' or 'VIR' prefix. All local scope variable names are exempt, and global > +variables are exempt, unless exported in a header file. > + > +*File names* > + > +File naming varies depending on the subdirectory. The preferred style is to > +have a 'vir' prefix, followed by a name which matches the name of the > +functions / objects inside the file. For example, a file containing an object > +'virHashtable' is stored in files 'virhashtable.c' and 'virhashtable.h'. > +Sometimes, methods which would otherwise be declared 'static' need to be > +exported for use by a test suite. For this purpose a second header file should > +be added with a suffix of 'priv'. e.g. 'virhashtablepriv.h'. USe of > +underscores in file names is discouraged when using the 'vir' prefix style. > +The 'vir' prefix naming applies to src/util, src/rpc and tests/ directories. > +Most other directories do not follow this convention. > + > + > + > +*Enum type & field names* > + > +All enums should have a 'vir' prefix in their typedef name, and each following > +word should have its first letter in uppercase. The enum name should match the > +typedef name with a leading underscore. The enum member names should be in all > +uppercase, and use an underscore to separate each word. The enum member name > +prefix should match the enum typedef name. > + > + typedef enum _virSocketType virSocketType; > + enum _virSocketType { > + VIR_SOCKET_TYPE_IPV4, > + VIR_SOCKET_TYPE_IPV6, > + }; > + > + > +*Struct type names* > + > +All structs should have a 'vir' prefix in their typedef name, and each > +following word should have its first letter in uppercase. The struct name > +should be the same as the typedef name with a leading underscore. A second > +typedef should be given for a pointer to the struct with a 'Ptr' suffix. > + > + typedef struct _virHashTable virHashTable; > + typedef virHashTable *virHashTablePtr; > + struct _virHashTable { > + ... > + }; > + I personally would prefer this style: typedef struct _virHashTable { ... } virHashTable, *virHashTablePtr; This is done for example in src/conf/device_conf.h. Subjectively, it is much easier to read, but objectively, it is more concise and enhances discoverability. For example, in src/conf/domain_conf.h the typedef are at the beginning of the file separated from the definition of the struct. If I want to look up a virDomainDiskDefPtr it requires two jumps.