/************************************************************************
 *                                                                      *
 *                      copyright Richard Bornat 1981                   *
 *                                                                      *
 ************************************************************************/

/* Modified 30/4/82 to add Next Page and Last Page control chars  -PLS */
/*    "     20/5/82 to add Execute Cmd & stay in edmode ctrl char -PLS */
/*    "     25/5/82 to add diag_printed flag external declaration -PLS */
/*    "     18/12/82 to add tab width param external declaration  -PLS */
/*    "     22/12/82 to add second unix buff external declaration -PLS */
/*    "     15/2/83 to add Read Pipe char for interactive compile -PLS */
/*    "     17/2/84 to add Overtype mode toggle char & flag extrn -PLS */
/*    "     13/4/84 to add tab preserve flag external declaration -PLS */

#define true 1
#define false 0

/* alternative versions, forced by the MAD design of setjmp and longjmp.
 * Come back BCPL, you are lovely.
 */
#define OK 1
#define NOT_OK (-1)

/* editor modes - defined as 2 and -2 for non-conflict with OK/NOT_OK.
 * (see beginning of mainloop procedure)
 */

#define INMODE 2
#define EDMODE (-2)

/* screen size parameters - variables initialised
 * from the characteristics of the terminal (see
 * ttysetup procedure)
 */
extern int nrows, ncols;

#define BELLMARGIN      (ncols/5*4)
	/* 64 chars per line */
#define ENOUGH          131
	/* enough for one screen line */

#define MARGIN          2
	/* room for line tag */

/* condition of end and top of file */
#define TOF (topl==0)
#define EOF (topl+LASTINROW>=maxl)

/* number of letters in the alphabet! */
#define NLETTS 26

/* input character classes */
#define IGN             0
#define ONE             1
#define TWO             2
#define TAB             3
#define MODIFY          4
#define SPACE           5
#define CR              6
#define NL              7
#define WLEFT           8
#define WRIGHT          9
#define LEFT            10
#define RIGHT           11
#define UP              12
#define DOWN            13
#define CONTROL         14
#define SPECIAL         15
#define LSTART          16      /* start of line */
#define LEND            17      /* end of line */
#define TOPSCREEN       18      /* top of screen */
#define BOTSCREEN       19      /* bottom of screen */
#define NEXTPAGE        20      /* same as " command - UMIST */
#define LASTPAGE        21      /* same as & command - UMIST */

/* characters which are commands */
#define SEND            30      /* modify interpretation of next line typed */
#define ENTERedit       31      /* wipe edit line and enter edit mode */
#define CHMODE          32      /* change mode (input <-> command) */
#define COMMAND         33      /* execute command shown in command line */
#define CMDSTAY         34      /* execute cmd and stay in cmd line - UMIST */
#define READPIPE        35      /* read in next compiler error msg - UMIST */
#define OVER            36      /* overtype/insert mode toggle - UMIST */

/* erasing commands */
#define RUBOUT          40      /* erase PREVIOUS character */
#define ERASE           41      /* erase PRESENT character */
#define WRUBOUT         42      /* erase PREVIOUS word */
#define WERASE          43      /* erase PRESENT word */
#define HEADRUBOUT      44      /* erase row up to cursor */
#define TAILERASE       45      /* erase row from cursor */
#define LINEERASE       46      /* delete entire line    */

#define LMIDDLE         60      /*  move to middle of line */

/* normal/dlog input discrimination */
#define NORMAL_INPUT (tty_input==std_in)

/* input channels */
#define STD_IN 0
#define STD_OUT 1
#define STD_TER 2

/* structure definitions */

struct iobuf
 { int fildes;
    int nleft;
    char *nextp;
    char buf[512];
 };

struct CURSOR
 { int row;
    int col;
 };


/*
 * external structures
 */
extern struct CURSOR virt_c,real_c;
extern struct CURSOR in_c, edit_c;
extern char **rowmap, **auxscreen;
extern char auxl[];
extern unsigned l_offset[];
extern char f_cache[];
extern char ictab[], ectab[];
extern char filename[], tempname[];
extern char pidname[], pathname[];
extern char tailname[];
extern char dlogname[];
/* things preserved in dlog file */
extern char erow[ENOUGH];
extern int b_range[NLETTS], e_range[NLETTS];
extern char old_search[ENOUGH];
extern char old_pat[ENOUGH];
extern char unixbuffer[ENOUGH];
extern char plusbuffer[ENOUGH];       /* separate unix buff for '+' command */
/*
 * external variables
 */

extern char *curr_break;
extern int topl, maxl;
extern int txin, tbout;
extern int ringing;
extern int mode;
extern int toprow,bottomrow,leftcol,rightcol;
extern int tmp_changed;
extern int filewritten;
extern int dlogger, tty_input;
extern int std_in, std_out, std_ter;
extern int setup_done; /* ttysetup */
extern int modopt; /* to say whether a modifier has been selected */
extern int Pswitch, Prows, Pcols; /* to say whether io is from pipe */
extern int editright;
extern int diag_printed;        /* to say if a diagnostic has been printed */
extern int tabsiz;              /* current tab width */
extern int tab_preserve;        /* true if not expanding tabs on input */
extern int overtype;            /* true if in overtype mode */

/*
 * external functions (some included here for the benefit
 *      of lint).
 */

extern int itoe();
extern int etoi();
extern int mainloop();
extern int do_command();
extern int set_dbug(), unset_dbug(), dbug();
extern void (*ttyinterrupt)(int);
extern char lastchar();
extern char **newscreen();
extern char lcase();

/*
 * variables to address the screen
 */


extern int NINROWS;        /* (nrows-1) */
extern int LASTINROW;      /* (nrows-2) */
extern int EDITROW;        /* (nrows-1) */
extern int FOOTROW;        /* (nrows-1) */
extern int SCROLL;         /* (nrows/3) */
extern int RIGHTCOL;       /* (ncols-1) */