vis-core.h

   1 #ifndef VIS_CORE_H
   2 #define VIS_CORE_H
   3
   4 #include <setjmp.h>
   5 #include "vis.h"
   6 #include "text.h"
   7 #include "text-regex.h"
   8 #include "map.h"
   9 #include "ring-buffer.h"
  10
  11 /* a mode contains a set of key bindings which are currently valid.
  12  *
  13  * each mode can specify one parent mode which is consultated if a given key
  14  * is not found in the current mode. hence the modes form a tree which is
  15  * searched from the current mode up towards the root mode until a valid binding
  16  * is found.
  17  *
  18  * if no binding is found, mode->input(...) is called and the user entered
  19  * keys are passed as argument. this is used to change the document content.
  20  */
  21 typedef struct Mode Mode;
  22 struct Mode {
  23         Mode *parent;                       /* if no match is found in this mode, search will continue there */
  24         Map *bindings;
  25         const char *name;                   /* descriptive, user facing name of the mode */
  26         const char *status;                 /* name displayed in the window status bar */
  27         const char *help;                   /* short description used by :help */
  28         bool isuser;                        /* whether this is a user or internal mode */
  29         void (*enter)(Vis*, Mode *old);           /* called right before the mode becomes active */
  30         void (*leave)(Vis*, Mode *new);           /* called right before the mode becomes inactive */
  31         void (*input)(Vis*, const char*, size_t); /* called whenever a key is not found in this mode and all its parent modes */
  32         void (*idle)(Vis*);                 /* called whenever a certain idle time i.e. without any user input elapsed */
  33         time_t idle_timeout;                /* idle time in seconds after which the registered function will be called */
  34         bool visual;                        /* whether text selection is possible in this mode */
  35 };
  36
  37 typedef struct {
  38         int count;        /* how many times should the command be executed? */
  39         Register *reg;    /* always non-NULL, set to a default register */
  40         Filerange range;  /* which part of the file should be affected by the operator */
  41         size_t pos;       /* at which byte from the start of the file should the operation start? */
  42         size_t newpos;    /* new position after motion or EPOS if none given */
  43         bool linewise;    /* should the changes always affect whole lines? */
  44         const Arg *arg;   /* arbitrary arguments */
  45 } OperatorContext;
  46
  47 typedef struct {
  48         /* operator logic, returns new cursor position, if EPOS is
  49          * the cursor is disposed (except if it is the primary one) */
  50         size_t (*func)(Vis*, Text*, OperatorContext*);
  51 } Operator;
  52
  53 typedef struct { /* Motion implementation, takes a cursor postion and returns a new one */
  54         /* TODO: merge types / use union to save space */
  55         size_t (*cur)(Cursor*);
  56         size_t (*txt)(Text*, size_t pos);
  57         size_t (*file)(Vis*, File*, size_t pos);
  58         size_t (*vis)(Vis*, Text*, size_t pos);
  59         size_t (*view)(Vis*, View*);
  60         size_t (*win)(Vis*, Win*, size_t pos);
  61         enum {
  62                 LINEWISE  = VIS_MOTIONTYPE_LINEWISE,  /* should the covered range be extended to whole lines? */
  63                 CHARWISE  = VIS_MOTIONTYPE_CHARWISE,  /* scrolls window content until position is visible */
  64                 INCLUSIVE = 1 << 2,  /* should new position be included in operator range? */
  65                 IDEMPOTENT = 1 << 3, /* does the returned postion remain the same if called multiple times? */
  66                 JUMP = 1 << 4,
  67         } type;
  68 } Movement;
  69
  70 typedef struct {
  71         /* gets a cursor position and returns a file range (or text_range_empty())
  72          * representing the text object containing the position. */
  73         Filerange (*range)(Text*, size_t pos);
  74         enum {  /* whether the object should include the delimiting symbols or not */
  75                 INNER,
  76                 OUTER,
  77         } type;
  78 } TextObject;
  79
  80 /* a macro is just a sequence of symbolic keys as received from ui->getkey */
  81 typedef Buffer Macro;
  82 #define macro_release buffer_release
  83 #define macro_reset buffer_truncate
  84 #define macro_append buffer_append0
  85
  86 typedef struct {             /** collects all information until an operator is executed */
  87         int count;
  88         enum VisMotionType type;
  89         const Operator *op;
  90         const Movement *movement;
  91         const TextObject *textobj;
  92         const Macro *macro;
  93         Register *reg;
  94         enum VisMark mark;
  95         Arg arg;
  96 } Action;
  97
  98 struct File { /* shared state among windows displaying the same file */
  99         Text *text;                      /* data structure holding the file content */
 100         const char *name;                /* file name used when loading/saving */
 101         volatile sig_atomic_t truncated; /* whether the underlying memory mapped region became invalid (SIGBUS) */
 102         bool is_stdin;                   /* whether file content was read from stdin */
 103         struct stat stat;                /* filesystem information when loaded/saved, used to detect changes outside the editor */
 104         int refcount;                    /* how many windows are displaying this file? (always >= 1) */
 105         Mark marks[VIS_MARK_INVALID];    /* marks which are shared across windows */
 106         File *next, *prev;
 107 };
 108
 109 typedef struct {
 110         time_t state;           /* state of the text, used to invalidate change list */
 111         size_t index;           /* #number of changes */
 112         size_t pos;             /* where the current change occured */
 113 } ChangeList;
 114
 115 struct Win {
 116         Vis *vis;               /* editor instance to which this window belongs to */
 117         UiWin *ui;              /* ui object handling visual appearance of this window */
 118         File *file;             /* file being displayed in this window */
 119         View *view;             /* currently displayed part of underlying text */
 120         RingBuffer *jumplist;   /* LRU jump management */
 121         ChangeList changelist;  /* state for iterating through least recently changes */
 122         Mode modes[VIS_MODE_LAST]; /* overlay mods used for per window key bindings */
 123         Win *prev, *next;       /* neighbouring windows */
 124 };
 125
 126 struct Vis {
 127         Ui *ui;                              /* user interface repsonsible for visual appearance */
 128         File *files;                         /* all files currently managed by this editor instance */
 129         Win *windows;                        /* all windows currently managed by this editor instance */
 130         Win *win;                            /* currently active/focused window */
 131         Register registers[VIS_REG_INVALID]; /* registers used for yank and put */
 132         Macro macros[VIS_MACRO_INVALID];     /* recorded macros */
 133         Macro *recording, *last_recording;   /* currently (if non NULL) and least recently recorded macro */
 134         Macro *macro_operator;               /* special macro used to repeat certain operators */
 135         Win *prompt;                         /* 1-line height window to get user input */
 136         Win *prompt_window;                  /* window which was focused before prompt was shown */
 137         char prompt_type;                    /* command ':' or search '/','?' prompt */
 138         Mode *mode_before_prompt;            /* user mode which was active before entering prompt */
 139         Regex *search_pattern;               /* last used search pattern */
 140         char search_char[8];                 /* last used character to search for via 'f', 'F', 't', 'T' */
 141         int last_totill;                     /* last to/till movement used for ';' and ',' */
 142         int tabwidth;                        /* how many spaces should be used to display a tab */
 143         bool expandtab;                      /* whether typed tabs should be converted to spaces */
 144         bool autoindent;                     /* whether indentation should be copied from previous line on newline */
 145         Map *cmds;                           /* ":"-commands, used for unique prefix queries */
 146         Map *options;                        /* ":set"-options */
 147         Buffer input_queue;                  /* holds pending input keys */
 148         Buffer *keys;                        /* currently active keys buffer (either the input_queue or a macro) */
 149         Action action;                       /* current action which is in progress */
 150         Action action_prev;                  /* last operator action used by the repeat (dot) command */
 151         Mode *mode;                          /* currently active mode, used to search for keybindings */
 152         Mode *mode_prev;                     /* previsouly active user mode */
 153         volatile bool running;               /* exit main loop once this becomes false */
 154         int exit_status;                     /* exit status when terminating main loop */
 155         volatile sig_atomic_t cancel_filter; /* abort external command/filter (SIGINT occured) */
 156         volatile sig_atomic_t sigbus;        /* one of the memory mapped region became unavailable (SIGBUS) */
 157         sigjmp_buf sigbus_jmpbuf;            /* used to jump back to a known good state in the mainloop after (SIGBUS) */
 158         Map *actions;                        /* registered editor actions / special keys commands */
 159         lua_State *lua;                      /* lua context used for syntax highligthing */
 160         VisEvent *event;
 161 };
 162
 163 /** stuff used by multiple of the vis-* files */
 164
 165 /* TODO: make part of Vis struct? enable dynamic modes? */
 166 extern Mode vis_modes[VIS_MODE_LAST];
 167
 168 extern Movement moves[VIS_MOVE_INVALID];
 169
 170 extern Operator ops[VIS_OP_INVALID];
 171
 172 const char *expandtab(Vis *vis);
 173
 174 void macro_operator_stop(Vis *vis);
 175 void macro_operator_record(Vis *vis);
 176
 177 void action_reset(Action*);
 178
 179 void mode_set(Vis *vis, Mode *new_mode);
 180 Mode *mode_get(Vis *vis, enum VisMode mode);
 181
 182 #endif