A program that can automatically generate documentation and cross references for
a C program.
The input is any C program with appropriate comments and the output is LaTeX,
HTML, RTF or SGML files.
The name of the program is cxref.
Usage: cxref filename [ ... filename]
[-Odirname] [-Nbasename] [-Rdirname]
[-all-comments] [-no-comments]
[-verbatim-comments] [-block-comments]
[-xref[-all][-file][-func][-var][-type]]
[-warn[-all][-comment][-xref]]
[-index[-all][-file][-func][-var][-type]]
[-raw]
[-latex209|-latex2e]
[-html20|-html32][-src]
[-rtf]
[-sgml]
[-Idirname] [-Ddefine] [-Udefine]
[-CPP cpp_program] [-- cpp_arg [ ... cpp_arg]]
Usage: cxref filename [ ... filename] -delete
[-Odirname] [-Nbasename] [-Rdirname]
filename
The name of the file to document, any number of files may be documented at a time.
-delete
The files named are to be deleted from the output directory and their entries in the cross reference database and main output files are to be removed.
-Odirname
The name of a directory to use for the output latex files and the location of the cross reference files that are created.
-Nbasename
The name to use for the first part of the output and cross reference files instead of cxref, the file extensions remain the same.
-Rdirname
When the source files are in more than one directory, set dirname to the name of the root directory of the source tree (use relative path if easier e.g. `-R../..'). This will then run cxref from that root directory and the `-Odirname' must be relative to that directory.
-all-comments
In case you think that the existing comments might work,
(see below for description of special comments).
[Danger! This option can produce weird results.]
-no-comments
Ignores all comments, useful if you just want the cross references and not the documentation.
-verbatim-comments
When the comments that you have in the code are formatted
in a predetermined style that you want to preserve on the
output, this option will force them not to be reformatted.
[Note, this is for file and function comments only.]
-block-comments
When the comments in the program are formatted in the `block'
style (with a leading `*' character on every line), this option
will remove that character from the output.
[Works for a single `*', `+', `|' or `:' on each line.]
-xref
Produce cross referencing information (see below).
-all
All cross references.
-file
Cross references for files.
-func
Cross references for functions.
-var
Cross references for variables.
-type
Cross references for types.
-warn
Produce warnings, the options must be concatenated together:
-all
All warnings.
-comment
Warn of missing comments.
-xref
Warn of missing cross references.
-index
Produce a cross reference index, the options must be concatenated together:
-all
All indexes.
-file
Index of files.
-func
Index of functions.
-var
Index of variables.
-type
Index of types.
-raw
Produce a raw form of output, not really of much use except with -warn.
-latex209
Produce a LaTeX file to document each of the source files and also an extra file that includes each of these files. (Using the LaTeX version 2.09 format.)
-latex2e
Produce the LaTeX file described above for use with the LaTeX2e version of LaTeX.
-html20
Produce an HTML file to document each of the source files and a main file to reference each of these files. (using the HTML 2.0 standard, no tables).
-html32
Produce the HTML file described above but using HTML 3.2.
-rtf
Produce a Rich Text Format (RTF) file to document the source file.
-html20-src
Produce the HTML v2.0 output and a HTML version of the source file with links into it.
-html32-src
Produce the HTML v3.2 output and a HTML version of the source file with links into it.
-sgml
Produce an SGML file to document the source file. (Using the LinuxDoc DTD).
-Idirname
GCC option to specify the path for include files.
-Ddefine
GCC option to define a pre-processor symbol.
-Udefine
GCC option to undefine a pre-processor symbol.
-CPP program
The name of the program to use instead of the compile time default. The program must be able to perform all of the actions that `gcc -E -C -dD' does to work. If the program takes arguments then the whole thing needs to be in quotes so that it is interpreted as a single argument to cxref.
-- arg ... arg
Extra arguments to be passed to the pre-processor can be placed after the `--' separator.
To simplify using cxref on existing source code, there is now a shell script that will call the C compiler and then call cxref to process the source file. This means that it can be used as a drop in replacement for CC in Makefiles and the like.
Usage: cxref-cc [usual cc options]
The name of the source file is extracted from the list of options as well as the `-D*', `-I*', `-U*' flags and when the C compiler exits succesfully cxref will be called. The name of the C compiler to use is controlled by the CXREFCC environment variable, or if this is not set then the CC environment variable, or failing this just gcc.
Using this script requires the use of a `.cxref' configuration file to contain the options since there is nowhere to put the options on the command line for the C compiler.
This will only cross-reference and document the C source files since they are the only ones that are compiled, but it will make sure that they are cross-referenced with the correct options etc.
These command line arguments can also be put into a file named `.cxref' instead of on the command line. When cxref is run the arguments to the program are interpreted in the following order.
This means that in a multi-directory source tree, each sub-directory can have a `.cxref' file containing just the line `-R..' or appropriate. The main directory can have a `.cxref' file containing the remainder of the options. This removes completely the need to have any options on the command line apart from the source file names.
The format of the `.cxref' file is any number of lines, each one containing a single command line argument (equivalent to one of the argv). The only options that cannot be used are the names of source files themselves and the `-delete' option. Blank lines are ignored and lines starting with a '#' are comments.
The documentation for the program is produced from comments in the code that are
appropriately formatted. The cross referencing comes from the code itself and
requires no extra work.
The special comments are `/**** ****/' (for a file) and `/*++++ ++++*/' (for a
data object) any number of `*' or `+' can be used inside of the standard `/*'
and `*/' comment delimiters in the comments, they are ignored.
If a comment line starts with whitespace and is followed by `+html+' then the
rest of the line is included only in the HTML output, and is not processed so it
can include HTML markup, `-html-' means that the rest of the line is included in
all except the HTML output. The same also applies to the other output formats,
`+none+' can be used for lines not to appear in any output. The exception to
this is that the raw output does not do any checking and will output all lines.
In any situation where a comment follows a `,', `;' or `)' separated only by
spaces and tabs, the comment is pushed to before the punctuation to apply to
object there.
The program is implemented using a full ANSI C grammar parser with some GCC
extensions, this means that the style of the code is unimportant, only the
content and comments.
To simplify the insertion of comments that will be parsed by cxref, the file
cxref.el
provides a number of Emacs lisp functions. To use them add the line
(load "cxref")
to your `.emacs' file or type M-x load-file cxref.el
from
within Emacs.
The functions and key bindings are:
Adds file comments, a /** **/ header at the top of the file and if it is a .h file then it also adds a #ifndef, #define at the beginning and #endif at the end to stop multiple inclusions.
Adds comments to a function, the cursor must be on the line containing the start of the function definition when this function is called. The /*+ ... +*/ comment that is added is of the header type (see the examples) not inline.
Adds a leading comment to the variable or other definition on the current line.
Adds a trailing comment at the end of the line.
Adds an inline comment that is ignored by cxref.
To improve the output that is available a modified version of the GNU CPP V2.7.2
is supplied (named cxref-cpp).
This modified C preprocessor allows for a finer control over some features of
the preprocessing that are not important for a compiler. In a standard
preprocessor, the preprocessor directives are intended for use only by the
preprocessor, so passing the information through is not important.
With cxref-cpp, there are two features that are different to the standard GNU
CPP:
The cross referencing is performed for the following items
The default LaTeX output is a file for each of the source files with one extra
file `cxref.tex' that includes each of the other files. This is to allow a
makefile to only update the changed files (although the references may require
all of the files to be checked again). When the cxref.tex file has been written
it can be modified by the user, any new files that are added are added at the
end of the source code section, the rest of the file being unchanged.
The index is written to a file called `cxref.apdx.tex' and cxref.tex is updated
to refer to it.
Also written out are three LaTeX style files `page.sty', `fonts.sty' and
`cxref.sty'. These set up the page to use a smaller margin and smaller fonts to
allow more to appear on a page and also define the new commands for typesetting
the cxref output.
(The file names `cxref.tex' and `cxref.apdx.tex' are different if the `-N'
option is used.)
The two different forms of LaTeX output are selected by using the -latex209 or
the -latex2e options. These select between two sets of output that can be used
with those two different versions of LaTeX.
The default HTML output is a file for each of the source files with one extra
file `cxref.html' that includes each of the other files. This is to allow a
makefile to only update the changed files (although the references may require
all of the files to be checked again). When the cxref.html file has been
written it can be modified by the user, any new files that are added are added
at the end before the table of contents, the rest of the file being unchanged.
The index is written to a file called `cxref.apdx.html' and cxref.html is
updated to refer to it.
(The file names `cxref.html' and `cxref.apdx.html' are different if the `-N'
option is used.)
The two different forms of HTML output are selected by using the -html20 or the
-html32 options. These select between two sets of output that comply with the
HTML 2.0 and 3.2 definitions, they differ in their use of tables.
Rich Text Format is a fairly low level page description format devised by
Microsoft. It is not a well defined and easy to understand standard as are the
other formats, but it is popular for document exchange.
There is a single output file for each of the source files and an index file.
Since SGML is a meta-language it is necessary to define the layout elements as
well as provide the information. The cxref output uses the LinuxDoc document
format and is designed for use with the SGMLtools programs
(http://www.sgmltools.org/).
There is a single output file for each of the source files and an index file.
There is a list of frequently asked questions and their answers for the cxref program in the FAQ file. A list of improvements planned for future versions of the program are listed in the file TODO.
More up-to-date information can be found on the World Wide Web at the cxref homepage, reached via the author's homepage http://www.gedanken.demon.co.uk/.
If you wish to submit bug reports or other comments about the program then email the author amb@gedanken.demon.co.uk and put cxref in the subject line.
The cxref program was written by Andrew M. Bishop in 1995,96,97,98,99.
The cxref program is copyright Andrew M. Bishop 1995,96,97,98,99.
The cxref-cpp program is copyright Free Software Foundation, Inc.
The cxref and cxref-cpp programs can be freely distributed according to the
terms of the GNU General Public License (see the file `COPYING').