The CommandProcessor is the interface to install a run-time menu into an embedded system.

Dependents:   A_CANAdapter USB2I2C

CommandProcessor.h

Committer:
WiredHome
Date:
2011-04-02
Revision:
6:1a0512faa75d
Parent:
4:283e35536097
Child:
7:0f058d664b21

File content as of revision 6:1a0512faa75d:

/// @file CommandProcessor.h defined the interface to the CommandProcessor
///
/// @mainpage
/// The CommandProcessor is the interface to install a run-time menu into an embedded system.
/// This contains the complete interface to the CommandProcessor.
///
/// @version 1.0
///
/// @note The CommandProcessor is text-based, because it is intended to interact with a
///       user.
///
/// The menu is designed to be interactively accessed, perhaps via a console interface
/// or a serial port. The actual interface to the user is provided by the application 
/// during initialization, so it can be connected to a serial port, or it could
/// be interface to CAN, telnet, or by some other method. 
///
/// The CommandProcessor has a few special features:
/// \li If the minimum number of characters of a command have been entered, the
///   user does not have to type the entire command. (e.g. 'He' will execute 
///   the command for 'Help', if no other command beings with 'He').
/// \li If the user does not type the entire set of characters, the command
///   will be rewritten to the output device with the entire command word.
/// \li The user is not permitted to enter an incorrect command (e.g. If 'Help'
///   is the only command started with 'Hel', the user cannot enter 'Heu'.
///   The CommandProcessor will trap the 'u' and issue a beep).
/// \li Simple editing of parameters to commands is permitted with \<bs\> to 
///   erase incorrect text.
/// \li Tab completion of a command is available - so long as the user has
///      typed at least the minimum number of unique characters. (e.g. 'He\<tab\>'
///   will be replaced with 'Help')
///    \li Command cancellation is available - just enter the \<esc\> key and
///   the buffer is erased.
/// \li The user is not permitted to enter text longer than the defined buffer,
///   to avoid buffer overrun and the possible memory damaging results.
///
/// The CommandProcessor is designed as a set of C functions, which makes it
/// reusable in more systems (as C++ compilers are not always available for
/// all micros).
///
/// Example:
/// @code
/// extern "C" {
/// #include "CommandProcessor.h"
/// }
/// 
/// RUNRESULT_T Who(char *p);
/// const CMD_T WhoCmd = {"who", "Shows who is logged on, or 'who id' for specifics", Who, visible};
/// 
/// RUNRESULT_T Who(char *p)
/// {
///     printf("\r\nwho...\r\n");
///     if (*p)
///         printf(" Sorry, no help for [%s]\r\n", p);
///     return runok;
/// }
/// 
/// int main(int argc, char* argv[])
/// {
///     CMDP_T * cp = GetCommandProcessor();
///     cp->Init(7, TRUE, 50, _kbhit, _getch, _putch, printf);
///     cp->Add(&WhoCmd);
/// 
///     while (cp->Run())
///     {
///         ;
///     }
///     cp->End();
///     return 0;
/// }
/// @endcode
///
/// @note Copyright &copy; 2011 by Smartware Computing, all rights reserved.
///       This program may be used by others as long as this copyright notice
///       remains intact.
/// @author David Smart
///
#ifndef COMMANDPROCESSOR_H
#define COMMANDPROCESSOR_H

#ifndef TRUE
#define TRUE 1        ///< Definition for TRUE, if not already provided
#define FALSE 0        ///< Definition for FALSE, if not already provided
#endif

/// @brief This type determines if menu items are visible to the Help system, or hidden.
/// @details This is used in the definition of the menu item.
typedef enum 
{
    invisible,        ///< use this value to have invisible (hidden) a menu in the Help
    visible            ///< use this value to have visible a menu in the Help
} VISIBLE_T;        ///< This determines if menu items are made visible in the Help system.

/// Callbacks that are executed return a value to indicate if the menu
/// should remain active
typedef enum
{
    runexit,        ///< use this return value to cause the menu (perhaps the program) to exit
    runok            ///< use this return value to keep the menu running
} RUNRESULT_T;

/// Adding items to the menu can succeed, or fail.
typedef enum
{
    addfailed,        ///< this indicates the menu was not added (usually failure to allocate memory)
    addok            ///< this indicates the menu was successfully added
} ADDRESULT_T;

/// Initialization can succeed, or fail.
typedef enum
{
    initfailed,        ///< this indicates that the menu system was not initialized (usually failure to allocate memory)
    initok            ///< this indicates that the menu system was successfully initialized
} INITRESULT_T;

/// This is the type for the basic callback, when a menu pick is activated.
///
/// The callback function is executed when a command is entered on the menu and \<enter\>
/// is signaled. If there is any additional text entered on the commandline, it is
/// passed to the callback.
///
/// example:
///        "Test1 ab c 123 567"
/// If "Test1" is a valid command, the corresponding function would be called
///    passing to that function the string "ab c 123 567". Note that the delimiter space
/// was removed.
/// 
///    @param p is a pointer to a character string
///    @returns RUNRESULT_T to indicate if the CommandProcessor should continue
///
typedef RUNRESULT_T (*MENU_CALLBACK)(char *p);

/// This defines the type for a single item to be added to the CommandProcessor menu.
///
/// This is defined in the application code, and a pointer to this item is passed to the
/// CommandProcessor to add this item to the menu system.
///
/// example:
///    @code
/// const CMD_T WhoCmd = {"who", "Shows who is logged on, or 'who id' for specifics", Who, visible};
/// @endcode
///
typedef const struct 
{
    char * command;                ///< a pointer to the command to match (e.g. 'Help')
    char * helptext;            ///< a pointer to some text to show when user types 'Help'
    MENU_CALLBACK callback;        ///< the function to call when user enters this command
    VISIBLE_T visible;            ///< a flag that determines if this command is visible in Help.
} CMD_T;

/// This is the CommandProcessor interface from the user application.
///
///    The user aquires a handle to this set of functions with the GetCommandProcessor command.
/// After this, the user may then initialize the CommandProcessor, add items to the menu,
/// cause the CommandProcessor to run periodically, and if need be the application can end
/// the CommandProcessor.
///
typedef const struct
{
    /// Init is the first function to call to configure the CommandProcessor.
    ///
    /// This function has a number of parameters, which make the CommandProcessor quite flexible.
    /// The user can enable a default menu, which can consist of the following functions.
    /// Note that when the [bit] is set, that menu item is enabled.
    /// * [3] Help - which in turn will show all the menu items and their brief descriptions
    /// * [2] Echo - which adds the echo command help
    /// * [1] About - just a tiny statement about the CommandProcessor itself
    /// * [0] Exit - a method to permit a consistent means to exit the CommandProcessor
    ///
    ///    @param defaultMenu enables various default menu items, based on the bit values.
    ///    @param kbhit is a user provided function to detect if a character is available for the CommandProcessor,
    ///            and when using standard io, you can typically use kbhit, or _kbhit as your system provides.
    ///    @param getch is a user provided function that provides a single character to the CommandProcessor
    ///    @param putch is a user provided function that permits the CommandProcessor to output a character
    ///    @param puts is a user provided function that permits the CommandProcessor to output a string
    ///        to which is automatically appended a \\n
    ///    @param caseinsensitive when TRUE, as the name implies, permits "help" and "HeLp" to function the same
    ///    @param maxCmdLen sets the memory allocation for the command buffer. This should be sized
    ///            to the maximum command, including any passed in text as parameters.
    /// @returns INITRESULT_T to indicate if the init was successful or failed
    INITRESULT_T (*Init)(
        int defaultMenu, 
        int caseinsensitive,
        int echo,
        int maxCmdLen,
        int (*kbhit)(void),
        int (*getch)(void),
        int (*putch)(int ch),
        int (*puts)(const char * s)
        );

    /// Add is called to add an item to the CommandProcessor menu
    ///
    ///    This passes in a reference to a user provided CMD_T item, which is
    ///    added to the menu system.
    ///
    /// @param m is a pointer to the user provided menu
    /// @returns ADDRESULT_T to indicate if the add was successful or failed
    ///
    ADDRESULT_T (*Add)(CMD_T * m);

    /// Run is the primary runtime entry point for the CommandProcessor.
    ///
    /// This function should be called periodically - fast enough not to miss user input.
    /// This function always returns, so if not character is available for the CommandProcessor
    /// it will return very fast. If there is a character (as detected by the kbhit callback),
    /// then it will process that character and determine what to do. It may then execute one
    /// of the menu functions. In this case, CPU cycles spent are based on the function 
    /// being executed.
    /// 
    /// @returns RUNRESULT_T to indicate if the CommandProcessor should remain active or if the 
    ///            command that was executed is requesting the CommandProcessor to exit.
    ///
    RUNRESULT_T (*Run)(void);
    
    /// Echo command permits turning the echo on and off
    ///
    /// When interactive with the user, it is best to have echo on, so they can see
    /// the prompt, but if this is simply slaved to another program, then the echo
    /// might need to be off to best manage the stream.
    ///
    /// @param echo turns the echo on (non-zero) or off (zero)
    /// @returns RUNRESULT_T to indicate if the CommandProcessor should remain active or if the 
    ///            command that was executed is requesting the CommandProcessor to exit.
    ///
    RUNRESULT_T (*Echo)(int echo);

    /// End if the function to be called when you want to gracefully end the CommandProcessor.
    ///
    ///    Calling this function causes the CommandProcessor to free any memory that was previously
    /// allocated by the Init and Add functions.
    RUNRESULT_T (*End)(void);            ///< Called to shutdown the processor
} CMDP_T;


/// The CommandProcessor is the interface to install a run-time menu into an embedded system.
/// This contains the complete interface to the CommandProcessor.
///
/// @version 1.0
///
/// @note The CommandProcessor is text-based, because it is intended to interact with a
///       user.
///
/// The menu is designed to be interactively accessed, perhaps via a console interface
/// or a serial port. The actual interface to the user is provided by the application 
/// during initialization, so it can be connected to a serial port, or it could
/// be interface to CAN, telnet, or by some other method. 
///
/// The CommandProcessor has a few special features:
/// \li If the minimum number of characters of a command have been entered, the
///   user does not have to type the entire command. (e.g. 'He' will execute 
///   the command for 'Help', if no other command beings with 'He').
/// \li If the user does not type the entire set of characters, the command
///   will be rewritten to the output device with the entire command word.
/// \li The user is not permitted to enter an incorrect command (e.g. If 'Help'
///   is the only command started with 'Hel', the user cannot enter 'Heu'.
///   The CommandProcessor will trap the 'u' and issue a beep).
/// \li Simple editing of parameters to commands is permitted with \<bs\> to 
///   erase incorrect text.
/// \li Tab completion of a command is available - so long as the user has
///      typed at least the minimum number of unique characters. (e.g. 'He\<tab\>'
///   will be replaced with 'Help')
///    \li Command cancellation is available - just enter the \<esc\> key and
///   the buffer is erased.
/// \li The user is not permitted to enter text longer than the defined buffer,
///   to avoid buffer overrun and the possible memory damaging results.
///
/// The CommandProcessor is designed as a set of C functions, which makes it
/// reusable in more systems (as C++ compilers are not always available for
/// all micros).
///
/// Example:
/// @code
/// extern "C" {
/// #include "CommandProcessor.h"
/// }
/// 
/// RUNRESULT_T Who(char *p);
/// const CMD_T WhoCmd = {"who", "Shows who is logged on, or 'who id' for specifics", Who, visible};
/// 
/// RUNRESULT_T Who(char *p)
/// {
///     printf("\r\nwho...\r\n");
///     if (*p)
///         printf(" Sorry, no help for [%s]\r\n", p);
///     return runok;
/// }
/// 
/// int main(int argc, char* argv[])
/// {
///     CMDP_T * cp = GetCommandProcessor();
///     cp->Init(7, TRUE, 50, _kbhit, _getch, _putch, printf);
///     cp->Add(&WhoCmd);
/// 
///     while (cp->Run())
///     {
///         ;
///     }
///     cp->End();
///     return 0;
/// }
/// @endcode
///
/// @note Copyright &copy; 2011 by Smartware Computing, all rights reserved.
///       This program may be used by others as long as this copyright notice
///       remains intact.
/// @author David Smart
///
/// GetCommandProcessor is called to get a handle to the CommandProcessor itself.
///
/// Call this function to get a handle to the CommandProcessor. After this is done, then
/// you can use that handle to activate the CommandProcessor methods.
///
/// example:
/// @code
///     CMDP_T * cp = GetCommandProcessor();
///     cp->Init(7, TRUE, 50, _kbhit, _getch, _putch, printf);
/// @endcode
/// 
/// @returns CMDP_T a handle to the CommandProcessor
///
#ifdef WIN32
CMDP_T * GetCommandProcessor(void);
#else // This is necessary for the mbed - not sure why.
extern "C" CMDP_T * GetCommandProcessor(void);
#endif



int mystrnicmp(const char *l, const char *r, size_t n);
#endif // COMMANDPROCESSOR_H