path: root/st.c

/* See LICENSE for licence details. */
#define _XOPEN_SOURCE 600
#include <ctype.h>
#include <errno.h>
#include <fcntl.h>
#include <limits.h>
#include <locale.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <signal.h>
#include <sys/ioctl.h>
#include <sys/select.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <unistd.h>
#include <X11/Xlib.h>
#include <X11/keysym.h>
#include <X11/Xutil.h>

#if   defined(LINUX)
 #include <pty.h>
#elif defined(OPENBSD)
 #include <util.h>
#elif defined(FREEBSD)
 #include <libutil.h>
#endif

/* Arbitrary sizes */
#define ESC_TITLE_SIZ 256
#define ESC_BUF_SIZ   256
#define ESC_ARG_SIZ   16
#define DRAW_BUF_SIZ  1024

#define SERRNO strerror(errno)
#define MIN(a, b)  ((a) < (b) ? (a) : (b))
#define MAX(a, b)  ((a) < (b) ? (b) : (a))
#define LEN(a)     (sizeof(a) / sizeof(a[0]))
#define DEFAULT(a, b)     (a) = (a) ? (a) : (b)    
#define BETWEEN(x, a, b)  ((a) <= (x) && (x) <= (b))
#define LIMIT(x, a, b)    (x) = (x) < (a) ? (a) : (x) > (b) ? (b) : (x)
#define ATTRCMP(a, b) ((a).mode != (b).mode || (a).fg != (b).fg || (a).bg != (b).bg)
#define IS_SET(flag) (term.mode & (flag))

/* Attribute, Cursor, Character state, Terminal mode, Screen draw mode */
enum { ATTR_NULL=0 , ATTR_REVERSE=1 , ATTR_UNDERLINE=2, ATTR_BOLD=4, ATTR_GFX=8 };
enum { CURSOR_UP, CURSOR_DOWN, CURSOR_LEFT, CURSOR_RIGHT, CURSOR_HIDE, CURSOR_DRAW, 
       CURSOR_SAVE, CURSOR_LOAD };
enum { GLYPH_SET=1, GLYPH_DIRTY=2 };
enum { MODE_WRAP=1, MODE_INSERT=2, MODE_APPKEYPAD=4 };
enum { ESC_START=1, ESC_CSI=2, ESC_OSC=4, ESC_TITLE=8, ESC_ALTCHARSET=16 };
enum { SCREEN_UPDATE, SCREEN_REDRAW };

typedef struct {
	char c;     /* character code  */
	char mode;  /* attribute flags */
	int fg;     /* foreground      */
	int bg;     /* background      */
	char state; /* state flags     */
} Glyph;

typedef Glyph* Line;

typedef struct {
	Glyph attr;	 /* current char attributes */
	int x;
	int y;
} TCursor;

/* CSI Escape sequence structs */
/* ESC '[' [[ [<priv>] <arg> [;]] <mode>] */
typedef struct {
	char buf[ESC_BUF_SIZ]; /* raw string */
	int len;			   /* raw string length */
	char priv;
	int arg[ESC_ARG_SIZ];
	int narg;			   /* nb of args */
	char mode;
} CSIEscape;

/* Internal representation of the screen */
typedef struct {
	int row;	/* nb row */  
	int col;	/* nb col */
	Line* line; /* screen */
	TCursor c;	/* cursor */
	char hidec;
	int top;	/* top	  scroll limit */
	int bot;	/* bottom scroll limit */
	int mode;	/* terminal mode flags */
	int esc;	/* escape state flags */
	char title[ESC_TITLE_SIZ];
	int titlelen;
} Term;

/* Purely graphic info */
typedef struct {
	Display* dis;
	Window win;
	Pixmap buf;
	int scr;
	int w;	/* window width	 */
	int h;	/* window height */
	int bufw; /* pixmap width  */
	int bufh; /* pixmap height */
	int ch; /* char height */
	int cw; /* char width  */
} XWindow; 

typedef struct {
	KeySym k;
	char s[ESC_BUF_SIZ];
} Key;

/* Drawing Context */
typedef struct {
	unsigned long col[256];
	XFontStruct* font;
	XFontStruct* bfont;
	GC gc;
} DC;

#include "config.h"

static void die(const char *errstr, ...);
static void draw(int);
static void execsh(void);
static void sigchld(int);
static void run(void);

static void csidump(void);
static void csihandle(void);
static void csiparse(void);
static void csireset(void);

static void tclearregion(int, int, int, int);
static void tcursor(int);
static void tdeletechar(int);
static void tdeleteline(int);
static void tinsertblank(int);
static void tinsertblankline(int);
static void tmoveto(int, int);
static void tnew(int, int);
static