.\" $NetBSD: menuc.1,v 1.5 2001/01/07 06:09:20 phil Exp $ .\" .\" Copyright 1997 Piermont Information Systems Inc. .\" All rights reserved. .\" .\" Written by Philip A. Nelson for Piermont Information Systems Inc. .\" .\" Redistribution and use in source and binary forms, with or without .\" modification, are permitted provided that the following conditions .\" are met: .\" 1. Redistributions of source code must retain the above copyright .\" notice, this list of conditions and the following disclaimer. .\" 2. Redistributions in binary form must reproduce the above copyright .\" notice, this list of conditions and the following disclaimer in the .\" documentation and/or other materials provided with the distribution. .\" 3. All advertising materials mentioning features or use of this software .\" must display the following acknowledgement: .\" This product includes software develooped for the NetBSD Project by .\" Piermont Information Systems Inc. .\" 4. The name of Piermont Information Systems Inc. may not be used to endorse .\" or promote products derived from this software without specific prior .\" written permission. .\" .\" THIS SOFTWARE IS PROVIDED BY PIERMONT INFORMATION SYSTEMS INC. ``AS IS'' .\" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE .\" ARE DISCLAIMED. IN NO EVENT SHALL PIERMONT INFORMATION SYSTEMS INC. BE .\" LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR .\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF .\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS .\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN .\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) .\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF .\" THE POSSIBILITY OF SUCH DAMAGE. .\" .Dd September 26, 1997 .Os .Dt MENUC 1 .Sh NAME .Nm menuc .Nd menu compiler .Sh SYNOPSIS menuc .Op Fl o Ar name .Ar file .Sh DESCRIPTION This implements a curses based menu system. A source file that describes menus, their options, and how to process the options is given to .Nm and produces both a .c and a .h file that implement the menu system. The standard base name of the files is .Pa menu_defs . The .Fl o Ar name can be used to specify a different base name. .Sh ENVIRONMENT .Bl -tag -width MENUDEF .It Ev MENUDEF Can be set to point to a different set of definition files for .Nm menuc . The current location defaults to .Pa /usr/share/misc . .El .Sh MENU DESCRIPTIONS The input .Ar file defines static menus and options for processing those menus. It also contains comments, initial C code that is required to provide for definitions and other code necssary for the menu system, and an option declaration if dynamic menus are requested. .Pp Comments may appear anywhere in the input .Ar file and are like a space in the input. They are like C comments starting with .Em /* and ending with .Em */. They are unlike C comments in that they may be nested. A comment does not end until a matching end comment is found. .Pp In many places, C code is included in the definition .Ar file. All C code is passed verbatim to the C output file. .Nm menuc comments do not start in C code and comments in the C code are passed verbatim to the output. The C comments are not recognized by .Nm menuc. In all cases, C code starts with a left brace .Em ({) and ends with the matching right brace .Em (}). It is important to recognize that in code segments, any brace will be counted, even if it is in a C comment inside the code. .Pp The .Ar file contains an initial (and optional) code block followed by any number of menu definition elements in any order. The initial code block usually contains includes of header files used by code in the menu code blocks later in the .Ar file. The file is free format, so the actual formatting of the input .Ar file is to the taste of the programmer. .Pp All other C code that will appear in an .Em action. This will be specified as .Em in later text. Such an action will appear as: .Dl action in the .Ar file. The .Em , if present is: .Dl ( endwin ) and specifies that the curses .Fn endwin function should be called before executing the code and then reinstating the current curses window after the code has been run. The .Em is as described above. .Pp There are four kinds of menu definition elements. The first one just declares whether the programmer wants dynamic menus available. The default is static menus only. The static menus are the ones defined by the menu definitions and do not change at run time. The dynamic menus provide the programmer with a method to create and modify menus during the running of the program. To include dynamic menus, one needs only add the declaration: .Dl allow dynamic menus ; The semicolon is required to terminate this declaration. This declaration may appear anywhere in the .Ar file, but usually appears before any menus are defined. .Pp The next element is a code block to execute if the curses screen can not be sucessfully initialized. The declaration .Dl error code ; tells the menu system to execute the associated code block if the initialization fails. If no code is provided, a default code block is used that prints .Dl Could not initialize curses. and exits. This element may appear anywhere in the .Ar file but usually appers before any menus are defined. .Pp The next element defines default options for menus. Each menu is built from a list of options. These options include the location of the upper left corner of the menu, whether there is a "box" drawn around the menu, whether the menu is scrollable, the menu's title, whether shortcut letters are allowed, whether a standard exit option should be included in the menu and text associated with the standard exit option. The general format is: .Dl default ; The options appear in three forms: .Dl variable = value .Dl [no] switch .Dl variable "string" .Pp The variables for the first form are .Va x, .Va y, .Va h, and .Va w. These specify the upper left (x,y) and the height (h) and width (w) of the menu window. The upper left is in the curses coordinate system. If not specified, the upper left is the upper left of the screen and the height and width of the menu window is computed from the menu definition. .Pp Options of the second form turn on or off (with the optional no) features of the menu system. The .Li box option turns on a box around the menu window. The .Li exit opton enables the standard exit option in the menus. The .Li scrollable option allows the menu to be scrollable if the menu window is smaller than the number of menu options. The .Li shortcut option prints a single character shortcut with each menu option. .Pp The third sets text variables. The variable .Va title sets the text title for the menus. The varible .Va exitstring sets the text for the exit menu option. .Pp The default declaration may appear multiple times. Each time, it sets the default values for menu definitions that follow in the .Ar file. In each menu definition, any or all of these default definitions may be overridden for that menu. .Pp The final element is the actual static menu menu definition. The format and order for a menu definition is: .Bd -ragged -offset indent menu ; .Ed .Pp Names are unquoted strings of alpha-numeric and underscore characters. They must start with an alpha character. In C source, a menu named .Nm foo is appears as .Nm MENU_foo. (Capitalization is important.) This is important, because the menu is displayed and processed by calling the function .Dl process_menu (MENU_foo) ; .Pp The options are a comma separated list of options as in the .Na default declaration. These override the options from the most recent default declaration. .Pp The display action is optional and provides C code to execute at each and every time the menu is displayed for processing. If it is included, the format is: .Dl display ; .Pp The bulk of the menu definition is the specification of the menu items. The general format of a menu item is: .Dl option , ; The .Em is the text displayed for the menu item. There may be an arbitrary number of these items. (If there are shortcuts in the menu, a practical limit of 51 should be recoginzed. It produces shortcuts a to w, y, z and A to Z. x is the shortcut for the exit item.) .Pp The .Em is a comma separated list of what to do when the item is selected. They may appear in any order. .Pp The first element processed when a menu item is selected is the associated action. The next element to be processed is the sub or next menu option. They are declared as: .Dl next menu .Dl sub menu The difference between these two is that a sub menu will return to the current menu when exited. The next menu will just replace the current menu and when exited, will return to where the current menu would have gone. Only one of menu element may be used for each menu item. Finally, after processing both the action and a sub menu, the current menu will be exited if the element .Dl exit is specified. .Em Note: If .Em exit is specified, next menu will not work because the menu system will exit the .Em current menu, even if current has been set by .Em next menu. .Pp After all menu items, the final two menu definition elements may appear. The exit action is optional and provides C code to execute in the process of exiting a menu. If it is included, the format is: .Dl exit ; .Pp The final part of the menu definition is the optional help string. The format is: .Dl help ; This text is displayed in a full page help window if the question mark is typed. The actual help text starts with a left brace .Em ({) and ends with the matching right brace .Em (}). The braces are not included in the help string, but all other characters between them are included. Newlines in the code translate to newlines in the help text. .Sh DYNAMIC MENUS If requested, .Nm menuc supports dynamic menus by allowing the user to create new menus. The related definitions for using dynamic menus are: .Bd -literal struct menudesc; typedef struct menu_ent { char *opt_name; int opt_menu; int opt_flags; int (*opt_action)(struct menudesc *); } menu_ent ; /* For opt_menu */ #define OPT_NOMENU -1 /* For opt_flags */ #define OPT_SUB 1 #define OPT_ENDWIN 2 #define OPT_EXIT 4 typedef struct menudesc { char *title; int y, x; int h, w; int mopt; int numopts; int cursel; int topline; menu_ent *opts; WINDOW *mw; char *helpstr; char *exitstr; void (*post_act)(void); void (*exit_act)(void); } menudesc ; /* defines for mopt field. */ #define MC_NOEXITOPT 1 #define MC_NOBOX 2 #define MC_SCROLL 4 #define MC_NOSHORTCUT 8 int new_menu (char * title, menu_ent * opts, int numopts, int x, int y, int h, int w, int mopt, void (*post_act)(void), void (*exit_act)(void), char * help); void free_menu (int menu_no); .Ed .Pp The .Ar title is the title displayed at the top of the menu. The .Ar opts is an array of menu entry definitions that has .Ar numopts elements. The programmer must build this array and fill in all of the fields before processing calling .Fn process_menu for the new menu. The fields of the .Ar opts may change at any time. For example, .Em opt_name may change as a result of selecting that option. When the menu is redisplayed, the new text is printed. Arguments, .Ar x, y, h and .Ar w are the same as the options in the menu description. .Ar mopt is the boolean options. Note, box, exit and shortcuts are enabled by default. You need to add option flags to turn them off or turn on scrollable menus. The options .Ar post_act, and .Ar exit_act are function pointers to the the display action and the exit action. If they are NULL, no call will be made. And finally, .Ar help is the text to display in a help screen. A NULL help pointer will disable the help feature for the menu. .Sh EXAMPLE The following is a simple menu definition file. It is complete in that the output of .Na menuc may be compiled into a complete program. For example, if the following was in a file called .Na example.mc, an executable program could be produced by the following commands. .Bd -literal -offset indent menuc -o example example.mc cc -o example example.c -lcurses .Ed A much more complete example is available with the source distribution in a subdirectory called .Em testm. .Bd -literal /* This is an example menu definition file for menuc. */ { #include #include /* Main program! This is often in a different file. */ int main() { process_menu (MENU_main); endwin(); return 0; } /* Example initialize function! */ void init_main() { } } default x=20, y=10, box, scrollable, exit; error action { fprintf (stderr, "Example Menu: Could not initialize curses.\n"); exit(1); }; menu main, title "Main Menu", no exit, no shortcut; display action { init_main(); }; option "Option 1", action (endwin) { printf ("That was option 1!\n"); sleep(3); }; option "Sub Menu", sub menu othermenu; option "Next Menu", next menu othermenu; option "Quit", exit; help { This is a simple help screen for an example menu definition file. }; menu othermenu, title "Sub/Next Menu", x=5, y=5, no box; option "Do Nothing!", action { }; .Ed .Sh FILES .Bl -item -width /usr/share/misc/menu_sys.def .It .Pa /usr/share/misc/menu_sys.def .El .Sh AUTHOR Philip A. Nelson for Piermont Information Systems Inc. Initial ideas for this were developed and implemented in Pascal at the Leiden University, Netherlands, in the summer of 1980.