$Id$ NOTE: Please improve this list! Dear (new) GRASS Developer, When submitting to GRASS CVS repositiory, please take care of following rules: 1. Get and read the GRASS 6 Programmer's Manual here: http://grass.itc.it/devel/index.php#prog or generate it from this source code (the programmer's manual is integrated in the source code in doxygen style): make htmldocs make pdfdocs 2. Use the directory structure to place your module appropriately into the source tree - libes go into lib/ - raster goes into raster/ - vector goes into vector/ - ... Consider to take a look at "GNU Coding Standards" http://www.gnu.org/prep/standards.html 3. Add a header section to each file you submit and make sure you include the copyright. The purpose section is meant to contain a general overview of the code in the file to assist other programmers that will need to make changes to your code. Example (ficticious header for a file called color.c) : /* **************************************************************************** * * MODULE: d.rast (or new higher level module name (eg GRASS core) * for 6.1) * AUTHOR(S): Original author unknown - probably CERL * John Doe - jdoe@some.where.org * PURPOSE: To provide storage and manipulation of colors used for * rendering the raster. The colors are stored in a doubly linked * list which must be initialized with InitColors() before it can * be used. Note that most linked list functionality (add, * remove, get) is supported, but their is no sorting * functionality. * COPYRIGHT: (C) 2005 by the GRASS Development Team * * This program is free software under the GNU General Public * License (>=v2). Read the file COPYING that comes with GRASS * for details. * *****************************************************************************/ The copyright protects your rights according to GNU General Public License (www.gnu.org). 4. - deleted. We don't want the $ ID $ in source code any more as it causes problems for the CVS branches. 5. To ensure that the software system continues to work, please include #include "config.h" in your files and make use of the various system dependencies contained therein. As one example of this, see src/paint/Interface/driverlib/io.c. Please refrain from declaring system functions within the software; include the proper header files (conditionally dependent on config.h macros if necessary) instead. 6. Order of include headers In general, headers should be included in the order: 1. Core system headers (stdio.h, ctype.h, ...) 2. Headers for non-core system components (X11, libraries). 3. Headers for core systems of the package being compiled (gis.h, glocale.h ...) 4. Headers for the specific library/program being compiled (geodesic.h, ...) Each class of header has an obligation to be compatible with those above it in the list, but not those below it. 7. Always specify the return type for ALL functions including those that return type "void", and insert return statements for ALL functions. Also, use ANSI C prototypes to declare your functions. Examples: void G_something(void); int G_somethingElse(int, int); void G_something(void) { /* Snipped out code */ return; } int G_somethingElse(int x, int y) { /* Snipped out code */ return(0); } 8. Use fprintf instead of printf. For errors and warnings please use the G_fatal_error() and G_warning() functions. General messages for the user should use G_message() while debug messages should use G_debug() whenever possible. G_message() output is not expected to be sent to pipe or file. For data output redirected to pipe or file, please use fprintf() and specify the stdout stream as follows: fprintf(stdout, ...); fflush(stdout); fflush(stdout) always required when using fprintf(stdout, ...). i18N: Add gettext macros with _("") (see ./locale/README for details) 9. Use the following GRASS library functions instead of the standard C functions. The reason for this is that the following functions ensure good programming practice (eg always checking if memory was allocated) and/or improves portability. PLEASE refer to the programmers manual for the proper use (eg determining if any casts are needed for arguments or return values) of these library functions. They may perform a task slightly different from their corresponding C library function, and thus, their use may not be the same. G_malloc() instead of malloc() G_calloc() instead of calloc() G_realloc() instead of realloc() G_getenv() instead of getenv() G_setenv() instead of setenv() G_unsetenv() instead of unsetenv() Could somebody please add others (please verify that they are useful and safe first) 10. Use the GRASS library function G_asprintf() instead of the standard C functions asprintf(), vsnprintf() and snprintf(). These functions are not portable or have other issues. Example: char *msg; G_asprintf(&msg, "%s", parameters); do_something_with_msg(); G_free(msg); Note that you should free memory when G_asprintf() is used. 11. Don't use the C++ comment style! This confuses several compilers. Use instead: /* C-comments */ If you want to comment code portions, use #ifdef notdef portion_to_be_commented; #endif This is safe comparing to nested /* comments */ Functions in the library must be documented in doxygen style to get them into the programmer's manual (generate with make pdfdocs or make htmldocs ). See lib/gis/*.c for examples. 12. PLEASE take the time to add comments throughout your code explaining what the code is doing. It will save a HUGE amount of time and frustration for other programmers that may have to change your code in the future. 13. Platform dependent code: Do not remove #ifdef __CYGWIN__ and/or #ifndef __CYGWIN__ lines and their encapsulated lines from source code (one example was that someone removed drand48 definition.) 14. Make sure a new line is at the end of each file 15. When writing Makefiles, use the current standard Example: see raster/r.info/Makefile or others 16. Have a look at ./INSTALL 17. Have a function included in your module which writes to the history file of the map (e.g. command line, parameters etc.). See eg raster/r.slope.aspect/main.c (the same applies to vector modules!) 18. Standard parser options: use G_define_standard_option() whenever possible to define standard module command line options. This will save you time, create fewer bugs, and make things easier on the translators. 19. Place the documentation in HTML format into description.html The easiest way to do this is to study an existing HTML page (to get the page style). The online WWW man pages will be updated every Saturday by CVS. 20. Add/update, if required the related d.m menu: display/d.m/menu.tcl 21. If you write a shell script: as a general principle, shell variables should almost always be quoted. Use only secure temp files, see g.tempfile and scripts/* for examples. 22. If you write a shell script and search for a command in $PATH, do NOT use the "which" command or the "type -p" command. Both commands are not supported on all platforms, thus causing problems for some people. As an alternative, please use code similar to the following shell script snippet which will perform the same function. In this case, the path of the grass60 command is saved if grass60 is found in $PATH. This won't recognize aliased command name. # Search for grass5 command in user's path for i in `echo $PATH | sed 's/^:/.:/ s/::/:.:/g s/:$/:./ s/:/ /g'` do if [ -f $i/grass5 ] ; then # Save the path of the grass60 command GRASS_PATH=$i/grass60 # Use the first one in user's path break fi done 23. Use "GRASS_TCLSH" and "GRASS_WISH" environment variables instead of "tclsh" and "wish" at the start of Tcl/Tk scripts. This allows users to override the default names, so that developers don't need worry about the shell names. Tcl script: #!/bin/sh # the next line restarts using tclsh \ exec $GRASS_TCLSH "$0" "$@" Tk script: #!/bin/sh # the next line restarts using wish \ exec $GRASS_WISH "$0" "$@" 24. For consistency, use README rather than README.txt for any README files. 25. GRASS/Environment variables: If you add a new variable, please follow the naming convention. All variables are described in lib/init/variables.html 26. Be sure to develop on top of the LATEST GRASS code (which is in CVS). You can re-check before submission with 'cvs diff': Either unified ("diff -u") or context ("diff -c") format. "Plain" diffs (the default format) are risky, because they will apply without warning to code which has been substantially changed; they are also harder to read than unified or context diffs. Such diffs should be made from the top-level directory, e.g. "cvs diff display/d.vect/main.c"; that way, the diff will include the pathname rather than just "main.c". 27. Tell the other developers about the new code using the following e-mail: grass5@grass.itc.it To subscribe to this mailing list, see http://grass.itc.it/devel/index.php 28. In case of questions feel free to contact the developers at the above mailing list. http://grass.itc.it/devel/index.php#submission ... [please add further hints if required]