root/usr.bin/vi/vi/vi.h
/*      $OpenBSD: vi.h,v 1.12 2022/12/26 19:16:04 jmc Exp $     */

/*-
 * Copyright (c) 1992, 1993, 1994
 *      The Regents of the University of California.  All rights reserved.
 * Copyright (c) 1992, 1993, 1994, 1995, 1996
 *      Keith Bostic.  All rights reserved.
 *
 * See the LICENSE file for redistribution information.
 *
 *      @(#)vi.h        10.19 (Berkeley) 6/30/96
 */

/* Definition of a vi "word". */
#define inword(ch)      (isalnum(ch) || (ch) == '_')

typedef struct _vikeys VIKEYS;

/* Structure passed around to functions implementing vi commands. */
typedef struct _vicmd {
        CHAR_T  key;                    /* Command key. */
        CHAR_T  buffer;                 /* Buffer. */
        CHAR_T  character;              /* Character. */
        u_long  count;                  /* Count. */
        u_long  count2;                 /* Second count (only used by z). */
        EVENT   ev;                     /* Associated event. */

#define ISCMD(p, key)   ((p) == &vikeys[(key)])
        VIKEYS const *kp;               /* Command/Motion VIKEYS entry. */
#define ISMOTION(vp)    ((vp)->rkp != NULL && F_ISSET((vp)->rkp, V_MOTION))
        VIKEYS const *rkp;              /* Related C/M VIKEYS entry. */

        /*
         * Historic vi allowed "dl" when the cursor was on the last column,
         * deleting the last character, and similarly allowed "dw" when
         * the cursor was on the last column of the file.  It didn't allow
         * "dh" when the cursor was on column 1, although these cases are
         * not strictly analogous.  The point is that some movements would
         * succeed if they were associated with a motion command, and fail
         * otherwise.  This is part of the off-by-1 schizophrenia that
         * plagued vi.  Other examples are that "dfb" deleted everything
         * up to and including the next 'b' character, while "d/b" deleted
         * everything up to the next 'b' character.  While this implementation
         * regularizes the interface to the extent possible, there are many
         * special cases that can't be fixed.  The special cases are handled
         * by setting flags per command so that the underlying command and
         * motion routines know what's really going on.
         *
         * The VM_* flags are set in the vikeys array and by the underlying
         * functions (motion component or command) as well.  For this reason,
         * the flags in the VICMD and VIKEYS structures live in the same name
         * space.
         */
#define VM_CMDFAILED    0x00000001      /* Command failed. */
#define VM_CUTREQ       0x00000002      /* Always cut into numeric buffers. */
#define VM_LDOUBLE      0x00000004      /* Doubled command for line mode. */
#define VM_LMODE        0x00000008      /* Motion is line oriented. */
#define VM_COMMASK      0x0000000f      /* Mask for VM flags. */

        /*
         * The VM_RCM_* flags are single usage, i.e. if you set one, you have
         * to clear the others.
         */
#define VM_RCM          0x00000010      /* Use relative cursor movement (RCM). */
#define VM_RCM_SET      0x00000020      /* RCM: set to current position. */
#define VM_RCM_SETFNB   0x00000040      /* RCM: set to first non-blank (FNB). */
#define VM_RCM_SETLAST  0x00000080      /* RCM: set to last character. */
#define VM_RCM_SETNNB   0x00000100      /* RCM: set to next non-blank. */
#define VM_RCM_MASK     0x000001f0      /* Mask for RCM flags. */

        /* Flags for the underlying function. */
#define VC_BUFFER       0x00000200      /* The buffer was set. */
#define VC_C1RESET      0x00000400      /* Reset C1SET flag for dot commands. */
#define VC_C1SET        0x00000800      /* Count 1 was set. */
#define VC_C2SET        0x00001000      /* Count 2 was set. */
#define VC_ISDOT        0x00002000      /* Command was the dot command. */
        u_int32_t flags;

        /*
         * There are four cursor locations that we worry about: the initial
         * cursor position, the start of the range, the end of the range,
         * and the final cursor position.  The initial cursor position and
         * the start of the range are both m_start, and are always the same.
         * All locations are initialized to the starting cursor position by
         * the main vi routines, and the underlying functions depend on this.
         *
         * Commands that can be motion components set the end of the range
         * cursor position, m_stop.  All commands must set the ending cursor
         * position, m_final.  The reason that m_stop isn't the same as m_final
         * is that there are situations where the final position of the cursor
         * is outside of the cut/delete range (e.g. 'd[[' from the first column
         * of a line).  The final cursor position often varies based on the
         * direction of the movement, as well as the command.  The only special
         * case that the delete code handles is that it will make adjustments
         * if the final cursor position is deleted.
         *
         * The reason for all of this is that the historic vi semantics were
         * defined command-by-command.  Every function has to roll its own
         * starting and stopping positions, and adjust them if it's being used
         * as a motion component.  The general rules are as follows:
         *
         *      1: If not a motion component, the final cursor is at the end
         *         of the range.
         *      2: If moving backward in the file, delete and yank move the
         *         final cursor to the end of the range.
         *      3: If moving forward in the file, delete and yank leave the
         *         final cursor at the start of the range.
         *
         * Usually, if moving backward in the file and it's a motion component,
         * the starting cursor is decremented by a single character (or, in a
         * few cases, to the end of the previous line) so that the starting
         * cursor character isn't cut or deleted.  No cursor adjustment is
         * needed for moving forward, because the cut/delete routines handle
         * m_stop inclusively, i.e. the last character in the range is cut or
         * deleted.  This makes cutting to the EOF/EOL reasonable.
         *
         * The 'c', '<', '>', and '!' commands are special cases.  We ignore
         * the final cursor position for all of them: for 'c', the text input
         * routines set the cursor to the last character inserted; for '<',
         * '>' and '!', the underlying ex commands that do the operation will
         * set the cursor for us, usually to something related to the first
         * <nonblank>.
         */
        MARK     m_start;               /* mark: initial cursor, range start. */
        MARK     m_stop;                /* mark: range end. */
        MARK     m_final;               /* mark: final cursor position. */
} VICMD;

/* Vi command table structure. */
struct _vikeys {                        /* Underlying function. */
        int      (*func)(SCR *, VICMD *);
#define V_ABS           0x00004000      /* Absolute movement, set '' mark. */
#define V_ABS_C         0x00008000      /* V_ABS: if the line/column changed. */
#define V_ABS_L         0x00010000      /* V_ABS: if the line changed. */
#define V_CHAR          0x00020000      /* Character (required, trailing). */
#define V_CNT           0x00040000      /* Count (optional, leading). */
#define V_DOT           0x00080000      /* On success, sets dot command. */
#define V_KEYW          0x00100000      /* Cursor referenced word. */
#define V_MOTION        0x00200000      /* Motion (required, trailing). */
#define V_MOVE          0x00400000      /* Command defines movement. */
#define V_OBUF          0x00800000      /* Buffer (optional, leading). */
#define V_RBUF          0x01000000      /* Buffer (required, trailing). */
#define V_SECURE        0x02000000      /* Permission denied if O_SECURE set. */
        u_int32_t flags;
        char    *usage;                 /* Usage line. */
        char    *help;                  /* Help line. */
};
#define MAXVIKEY        126             /* List of vi commands. */
extern VIKEYS const vikeys[MAXVIKEY + 1];
extern VIKEYS const tmotion;            /* XXX Hacked ~ command. */

/* Character stream structure, prototypes. */
typedef struct _vcs {
        recno_t  cs_lno;                /* Line. */
        size_t   cs_cno;                /* Column. */
        CHAR_T  *cs_bp;                 /* Buffer. */
        size_t   cs_len;                /* Length. */
        CHAR_T   cs_ch;                 /* Character. */
#define CS_EMP  1                       /* Empty line. */
#define CS_EOF  2                       /* End-of-file. */
#define CS_EOL  3                       /* End-of-line. */
#define CS_SOF  4                       /* Start-of-file. */
        int      cs_flags;              /* Return flags. */
} VCS;

int     cs_bblank(SCR *, VCS *);
int     cs_fblank(SCR *, VCS *);
int     cs_fspace(SCR *, VCS *);
int     cs_init(SCR *, VCS *);
int     cs_next(SCR *, VCS *);
int     cs_prev(SCR *, VCS *);

/*
 * We use a single "window" for each set of vi screens.  The model would be
 * simpler with two windows (one for the text, and one for the modeline)
 * because scrolling the text window down would work correctly then, not
 * affecting the mode line.  As it is we have to play games to make it look
 * right.  The reason for this choice is that it would be difficult for
 * curses to optimize the movement, i.e. detect that the downward scroll
 * isn't going to change the modeline, set the scrolling region on the
 * terminal and only scroll the first part of the text window.
 *
 * Structure for mapping lines to the screen.  An SMAP is an array, with one
 * structure element per screen line, which holds information describing the
 * physical line which is displayed in the screen line.  The first two fields
 * (lno and off) are all that are necessary to describe a line.  The rest of
 * the information is useful to keep information from being re-calculated.
 *
 * The SMAP always has an entry for each line of the physical screen, plus a
 * slot for the colon command line, so there is room to add any screen into
 * another one at screen exit.
 *
 * Lno is the line number.  If doing the historic vi long line folding, off
 * is the screen offset into the line.  For example, the pair 2:1 would be
 * the first screen of line 2, and 2:2 would be the second.  In the case of
 * long lines, the screen map will tend to be staggered, e.g., 1:1, 1:2, 1:3,
 * 2:1, 3:1, etc.  If doing left-right scrolling, the off field is the screen
 * column offset into the lines, and can take on any value, as it's adjusted
 * by the user set value O_SIDESCROLL.
 */
typedef struct _smap {
        recno_t  lno;           /* 1-N: Physical file line number. */
        size_t   coff;          /* 0-N: Column offset in the line. */
        size_t   soff;          /* 1-N: Screen offset in the line. */

                                /* vs_line() cache information. */
        size_t   c_sboff;       /* 0-N: offset of first character byte. */
        size_t   c_eboff;       /* 0-N: offset of  last character byte. */
        u_int8_t c_scoff;       /* 0-N: offset into the first character. */
        u_int8_t c_eclen;       /* 1-N: columns from the last character. */
        u_int8_t c_ecsize;      /* 1-N: size of the last character. */
} SMAP;
                                /* Macros to flush/test cached information. */
#define SMAP_CACHE(smp)         ((smp)->c_ecsize != 0)
#define SMAP_FLUSH(smp)         ((smp)->c_ecsize = 0)

                                /* Character search information. */
typedef enum { CNOTSET, FSEARCH, fSEARCH, TSEARCH, tSEARCH } cdir_t;

typedef enum { AB_NOTSET, AB_NOTWORD, AB_INWORD } abb_t;
typedef enum { Q_NOTSET, Q_VNEXT, Q_VTHIS } quote_t;

/* Vi private, per-screen memory. */
typedef struct _vi_private {
        VICMD   cmd;            /* Current command, motion. */
        VICMD   motion;

        /*
         * !!!
         * The saved command structure can be modified by the underlying
         * vi functions, see v_Put() and v_put().
         */
        VICMD   sdot;           /* Saved dot, motion command. */
        VICMD   sdotmotion;

        CHAR_T *keyw;           /* Keyword buffer. */
        size_t  klen;           /* Keyword length. */
        size_t  keywlen;        /* Keyword buffer length. */

        CHAR_T  rlast;          /* Last 'r' replacement character. */
        e_key_t rvalue;         /* Value of last replacement character. */

        EVENT  *rep;            /* Input replay buffer. */
        size_t  rep_len;        /* Input replay buffer length. */
        size_t  rep_cnt;        /* Input replay buffer characters. */

        mtype_t mtype;          /* Last displayed message type. */
        size_t  linecount;      /* 1-N: Output overwrite count. */
        size_t  lcontinue;      /* 1-N: Output line continue value. */
        size_t  totalcount;     /* 1-N: Output overwrite count. */

                                /* Busy state. */
        int     busy_ref;       /* Busy reference count. */
        int     busy_ch;        /* Busy character. */
        size_t  busy_fx;        /* Busy character x coordinate. */
        size_t  busy_oldy;      /* Saved y coordinate. */
        size_t  busy_oldx;      /* Saved x coordinate. */
        struct timespec busy_ts;/* Busy timer. */

        char   *ps;             /* Paragraph plus section list. */

        u_long  u_ccnt;         /* Undo command count. */

        CHAR_T  lastckey;       /* Last search character. */
        cdir_t  csearchdir;     /* Character search direction. */

        SMAP   *h_smap;         /* First slot of the line map. */
        SMAP   *t_smap;         /* Last slot of the line map. */

        /*
         * One extra slot is always allocated for the map so that we can use
         * it to do vi :colon command input; see v_tcmd().
         */
        recno_t sv_tm_lno;      /* tcmd: saved TMAP lno field. */
        size_t  sv_tm_coff;     /* tcmd: saved TMAP coff field. */
        size_t  sv_tm_soff;     /* tcmd: saved TMAP soff field. */
        size_t  sv_t_maxrows;   /* tcmd: saved t_maxrows. */
        size_t  sv_t_minrows;   /* tcmd: saved t_minrows. */
        size_t  sv_t_rows;      /* tcmd: saved t_rows. */
#define SIZE_HMAP(sp)   (VIP(sp)->srows + 1)

        /*
         * Macros to get to the head/tail of the smap.  If the screen only has
         * one line, HMAP can be equal to TMAP, so the code has to understand
         * the off-by-one errors that can result.  If stepping through an SMAP
         * and operating on each entry, use sp->t_rows as the count of slots,
         * don't use a loop that compares <= TMAP.
         */
#define _HMAP(sp)       (VIP(sp)->h_smap)
#define HMAP            _HMAP(sp)
#define _TMAP(sp)       (VIP(sp)->t_smap)
#define TMAP            _TMAP(sp)

        recno_t ss_lno; /* 1-N: vi_opt_screens cached line number. */
        size_t  ss_screens;     /* vi_opt_screens cached return value. */
#define VI_SCR_CFLUSH(vip)      ((vip)->ss_lno = OOBLNO)

        size_t  srows;          /* 1-N: rows in the terminal/window. */
        recno_t olno;           /* 1-N: old cursor file line. */
        size_t  ocno;           /* 0-N: old file cursor column. */
        size_t  sc_col;         /* 0-N: LOGICAL screen column. */
        SMAP   *sc_smap;        /* SMAP entry where sc_col occurs. */

#define VIP_CUR_INVALID 0x0001  /* Cursor position is unknown. */
#define VIP_DIVIDER     0x0002  /* Divider line was displayed. */
#define VIP_N_EX_PAINT  0x0004  /* Clear and repaint when ex finishes. */
#define VIP_N_EX_REDRAW 0x0008  /* Schedule SC_SCR_REDRAW when ex finishes. */
#define VIP_N_REFRESH   0x0010  /* Repaint (from SMAP) on the next refresh. */
#define VIP_N_RENUMBER  0x0020  /* Renumber screen on the next refresh. */
#define VIP_RCM_LAST    0x0040  /* Cursor drawn to the last column. */
#define VIP_S_MODELINE  0x0080  /* Skip next modeline refresh. */
#define VIP_S_REFRESH   0x0100  /* Skip next refresh. */
        u_int16_t flags;
} VI_PRIVATE;

/* Vi private area. */
#define VIP(sp) ((VI_PRIVATE *)((sp)->vi_private))

#define O_NUMBER_FMT    "%7lu "                 /* O_NUMBER format, length. */
#define O_NUMBER_LENGTH 8
#define SCREEN_COLS(sp)                         /* Screen columns. */   \
        ((O_ISSET((sp), O_NUMBER) ? (sp)->cols - O_NUMBER_LENGTH : (sp)->cols))

/*
 * LASTLINE is the zero-based, last line in the screen.  Note that it is correct
 * regardless of the changes in the screen to permit text input on the last line
 * of the screen, or the existence of small screens.
 */
#define LASTLINE(sp) \
        ((sp)->t_maxrows < (sp)->rows ? (sp)->t_maxrows : (sp)->rows - 1)

/*
 * Small screen (see vs_refresh.c, section 6a) and one-line screen test.
 * Note, both cannot be true for the same screen.
 */
#define IS_SMALL(sp)    ((sp)->t_minrows != (sp)->t_maxrows)
#define IS_ONELINE(sp)  ((sp)->rows == 1)

#define HALFTEXT(sp)                            /* Half text. */        \
        ((sp)->t_rows == 1 ? 1 : (sp)->t_rows / 2)
#define HALFSCREEN(sp)                          /* Half text screen. */ \
        ((sp)->t_maxrows == 1 ? 1 : (sp)->t_maxrows / 2)

/*
 * Next tab offset.
 *
 * !!!
 * There are problems with how the historical vi handled tabs.  For example,
 * by doing "set ts=3" and building lines that fold, you can get it to step
 * through tabs as if they were spaces and move inserted characters to new
 * positions when <esc> is entered.  I believe that nvi does tabs correctly,
 * but there are some historical incompatibilities.
 */
#define TAB_OFF(c)      COL_OFF((c), O_VAL(sp, O_TABSTOP))

/* If more than one screen being shown. */
#define IS_SPLIT(sp)    (TAILQ_NEXT((sp), q) || TAILQ_PREV((sp), _dqh, q))

/* Screen adjustment operations. */
typedef enum { A_DECREASE, A_INCREASE, A_SET } adj_t;

/* Screen position operations. */
typedef enum { P_BOTTOM, P_FILL, P_MIDDLE, P_TOP } pos_t;

/* Scrolling operations. */
typedef enum {
        CNTRL_B, CNTRL_D, CNTRL_E, CNTRL_F,
        CNTRL_U, CNTRL_Y, Z_CARAT, Z_PLUS
} scroll_t;

/* Vi common error messages. */
typedef enum {
        VIM_COMBUF, VIM_EMPTY, VIM_EOF, VIM_EOL,
        VIM_NOCOM, VIM_NOCOM_B, VIM_USAGE, VIM_WRESIZE
} vim_t;

#include "vi_extern.h"