apps/console/screen.c

   1 /*
   2     meinOS - A unix-like x86 microkernel operating system
   3     Copyright (C) 2008  Janosch Gräf <janosch.graef@gmx.net>
   4
   5     This program is free software: you can redistribute it and/or modify
   6     it under the terms of the GNU General Public License as published by
   7     the Free Software Foundation, either version 3 of the License, or
   8     (at your option) any later version.
   9
  10     This program is distributed in the hope that it will be useful,
  11     but WITHOUT ANY WARRANTY; without even the implied warranty of
  12     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13     GNU General Public License for more details.
  14
  15     You should have received a copy of the GNU General Public License
  16     along with this program.  If not, see <http://www.gnu.org/licenses/>.
  17 */
  18
  19 #include <stdlib.h>
  20 #include <stdint.h>
  21 #include <devfs.h>
  22 #include <string.h>
  23 #include <misc.h>
  24 #include <unistd.h>
  25 #include <ioport.h>
  26 #include <ctype.h>
  27
  28 #include "console.h"
  29
  30 #define VIDEOTEXT_WIDTH    80      // 80 Cols (chars per line)
  31 #define VIDEOTEXT_HEIGHT   25      // 25 Rows (lines)
  32 #define VIDEOTEXT_SIZE     4000    // Video size
  33 #define VIDEOTEXT_STDCOLOR 0x07    // Default color: black background, lightgray foreground
  34 #define VIDEOTEXT_STDCOL   0       // Default col
  35 #define VIDEOTEXT_STDROW   0       // Default row
  36
  37 #define SCREEN_DEFAULT_FONT "standard"
  38
  39 #define cursor_offset() (cursor.row*VIDEOTEXT_WIDTH+cursor.col)
  40
  41 // see http://files.osdev.org/mirrors/geezer/osd/graphics/modes.c
  42 // for changing fonts
  43
  44 static struct {
  45   int col;
  46   int row;
  47 } cursor,saved_cursor;
  48
  49 static struct {
  50   int linewrap;
  51   int bell_freq;
  52   int bell_dur;
  53   int color;
  54 } settings;
  55
  56 static uint16_t *videomem;
  57
  58 /**
  59  * Rings the bell
  60  *  @param freq Frequency
  61  *  @param dur Duration time
  62  */
  63 static void bell(int freq,int dur) {
  64   freq = 1193180/freq;
  65   outb(0x43,0xB6);
  66   outb(0x42,(uint8_t)freq);
  67   outb(0x42,(uint8_t)(freq>>8));
  68   outb(0x61,inb(0x61)|3);
  69   sleep(dur);
  70   outb(0x61,inb(0x61)&~3);
  71 }
  72
  73 /**
  74  * Clears screen
  75  */
  76 static void clearscreen() {
  77   memset(videomem,0,VIDEOTEXT_SIZE);
  78   cursor.col = VIDEOTEXT_STDCOL;
  79   cursor.row = VIDEOTEXT_STDROW;
  80 }
  81
  82 /**
  83  * Sets default settings
  84  */
  85 static void default_settings() {
  86   settings.linewrap = 1;
  87   settings.bell_freq = 440;
  88   settings.bell_dur = 100;
  89   settings.color = VIDEOTEXT_STDCOLOR;
  90 }
  91
  92 /**
  93  * Prints a character on screen
  94  *  @param chr Character
  95  */
  96 static int printchar(char chr) {
  97   size_t pos = cursor_offset();
  98   static int escape = 0;
  99   static char escape_buf[32];
 100
 101   if (escape) {
 102     escape_buf[(escape++)-1] = chr; // put byte in escape buffer
 103
 104     if (isalpha(chr)) { // escape code finished
 105       escape = 0;
 106       if (escape==1 && escape_buf[0]=='c') default_settings();           // reset device
 107       else if (escape==3 && memcmp(escape_buf,"[7h",3)==0) settings.linewrap = 1; // enable linewrap
 108       else if (escape==3 && memcmp(escape_buf,"[7l",3)==0) settings.linewrap = 0; // disable linewrap
 109       else if (escape_buf[0]=='[' && (escape_buf[escape-2]=='H' || escape_buf[escape-2]=='f')) { // set cursor position
 110         int row = -1;
 111         int col = -1;
 112         if (escape>3) sscanf(escape_buf,escape_buf[escape-2]=='H'?"[%d;%dH":"[%d;%df",&row,&col);
 113         if (row!=-1 && col!=-1) {
 114           cursor.col = col;
 115           cursor.row = row;
 116         }
 117         else {
 118           cursor.col = 0;
 119           cursor.row = 0;
 120         }
 121       }
 122       else if (escape_buf[0]=='[' && escape_buf[escape-2]=='A') {
 123         int up = 1;
 124         if (escape>3) sscanf(escape_buf,"[%dA",&up);
 125         if (cursor.row>0) cursor.row -= up;
 126       }
 127       else if (escape_buf[0]=='[' && escape_buf[escape-2]=='B') {
 128         int down = 1;
 129         if (escape>3) sscanf(escape_buf,"[%dB",&down);
 130         if (cursor.row<VIDEOTEXT_HEIGHT) cursor.row += down;
 131       }
 132       else if (escape_buf[0]=='[' && escape_buf[escape-2]=='C') {
 133         int left = 1;
 134         if (escape>3) sscanf(escape_buf,"[%dC",&left);
 135         if (cursor.col>0) cursor.col -= left;
 136       }
 137       else if (escape_buf[0]=='[' && escape_buf[escape-2]=='D') {
 138         int right = 1;
 139         if (escape>3) sscanf(escape_buf,"[%dD",&right);
 140         if (cursor.col<VIDEOTEXT_WIDTH) cursor.col += right;
 141       }
 142       else if (escape_buf[0]=='[' && (escape_buf[1]=='s' || escape_buf[1]=='7')) {
 143         memcpy(&saved_cursor,&cursor,sizeof(cursor));
 144       }
 145       else if (escape_buf[0]=='[' && (escape_buf[1]=='u' || escape_buf[1]=='8')) {
 146         memcpy(&cursor,&saved_cursor,sizeof(cursor));
 147       }
 148       else if (memcmp(escape_buf,"[K",2)==0) {
 149         memset(videomem+pos,0,(VIDEOTEXT_WIDTH-cursor.col+1)*2);
 150       }
 151       else if (memcmp(escape_buf,"[1K",3)==0) {
 152         memset(videomem+VIDEOTEXT_WIDTH*cursor.col,0,cursor.row*2);
 153       }
 154       else if (memcmp(escape_buf,"[2K",3)==0) {
 155         memset(videomem+VIDEOTEXT_WIDTH*cursor.col,0,VIDEOTEXT_WIDTH);
 156       }
 157       else if (memcmp(escape_buf,"[J",2)==0) {
 158         memset(videomem+VIDEOTEXT_WIDTH*cursor.col,0,(VIDEOTEXT_HEIGHT-cursor.row)*VIDEOTEXT_WIDTH*2);
 159       }
 160       else if (memcmp(escape_buf,"[1J",3)==0) {
 161         memset(videomem,0,cursor.row*VIDEOTEXT_WIDTH*2);
 162       }
 163       else if (memcmp(escape_buf,"[2J",3)==0) {
 164         clearscreen();
 165       }
 166     }
 167   }
 168   else if (chr=='\a') bell(settings.bell_freq,settings.bell_dur);
 169   else if (chr=='\b') cursor.col = (cursor.col-1>0)?(cursor.col-1):0;
 170   else if (chr=='\t') cursor.col = cursor.col+5;
 171   else if (chr=='\n') {
 172     cursor.row++;
 173     cursor.col = VIDEOTEXT_STDCOL;
 174   }
 175   else if (chr=='\f') clearscreen();
 176   else if (chr=='\r') cursor.col = VIDEOTEXT_STDCOL;
 177   else if (chr==0x1B) escape = 1;
 178   else if (chr>=' ') {
 179     *(videomem+pos) = (((uint16_t)settings.color)<<8)|chr;
 180     cursor.col++;
 181   }
 182
 183   if (cursor.col>=VIDEOTEXT_WIDTH) {
 184     cursor.col = cursor.col-VIDEOTEXT_WIDTH;
 185     cursor.row++;
 186   }
 187   while (cursor.row>=VIDEOTEXT_HEIGHT) {
 188     memcpy(videomem,videomem+VIDEOTEXT_WIDTH,VIDEOTEXT_SIZE-VIDEOTEXT_WIDTH*2);
 189     memset(videomem+VIDEOTEXT_WIDTH*(VIDEOTEXT_HEIGHT-1),0,VIDEOTEXT_WIDTH*2);
 190     cursor.row--;
 191   }
 192   return 1;
 193 }
 194
 195 /**
 196  * Writes characters to screen
 197  *  @param buffer Chars to write to screen
 198  *  @param count How many bytes to write to screen
 199  *  @param dev Device to write to
 200  *  @return How many bytes written
 201  */
 202 ssize_t onwrite(devfs_dev_t *dev,void *buffer,size_t count,off_t offset) {
 203   int i;
 204   int w = 0;
 205   for (i=0;i<count;i++) w += printchar(((char*)buffer)[i]);
 206   return w;
 207 }
 208
 209 /**
 210  * Initializes screen driver
 211  *  @return 0=success; -1=failure
 212  */
 213 int init_screen() {
 214   videomem = mem_getvga();
 215   if (videomem==NULL) return -1;
 216   memset(&saved_cursor,0,sizeof(saved_cursor));
 217   default_settings();
 218   clearscreen();
 219   return 0;
 220 }