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  * Updates hardware cursor
  75  */
  76 static void update_hwcursor() {
  77   uint32_t pos = cursor.row*VIDEOTEXT_WIDTH+cursor.col;
  78   outb(0x3D4,15);
  79   outb(0x3D5,pos);
  80   outb(0x3D4,14);
  81   outb(0x3D5,pos>>8);
  82 }
  83
  84 /**
  85  * Clears screen
  86  */
  87 static void clearscreen() {
  88   size_t i;
  89   for (i=0;i<VIDEOTEXT_WIDTH*VIDEOTEXT_HEIGHT;i++) videomem[i] = VIDEOTEXT_STDCOLOR<<8;
  90   cursor.col = VIDEOTEXT_STDCOL;
  91   cursor.row = VIDEOTEXT_STDROW;
  92   update_hwcursor();
  93 }
  94
  95 /**
  96  * Sets default settings
  97  */
  98 static void default_settings() {
  99   settings.linewrap = 1;
 100   settings.bell_freq = 440;
 101   settings.bell_dur = 100;
 102   settings.color = VIDEOTEXT_STDCOLOR;
 103 }
 104
 105 /**
 106  * Prints a character on screen
 107  *  @param chr Character
 108  */
 109 static int printchar(char chr) {
 110   size_t pos = cursor_offset();
 111   static int escape = 0;
 112   static char escape_buf[32];
 113
 114   if (escape) {
 115     escape_buf[(escape++)-1] = chr; // put byte in escape buffer
 116
 117     if (isalpha(chr)) { // escape code finished
 118       if (escape==1 && escape_buf[0]=='c') default_settings();           // reset device
 119       else if (escape==3 && memcmp(escape_buf,"[7h",3)==0) settings.linewrap = 1; // enable linewrap
 120       else if (escape==3 && memcmp(escape_buf,"[7l",3)==0) settings.linewrap = 0; // disable linewrap
 121       else if (escape_buf[0]=='[' && (escape_buf[escape-2]=='H' || escape_buf[escape-2]=='f')) { // set cursor position
 122         int row = -1;
 123         int col = -1;
 124         if (escape>3) sscanf(escape_buf,escape_buf[escape-2]=='H'?"[%d;%dH":"[%d;%df",&row,&col);
 125         if (row!=-1 && col!=-1) {
 126           cursor.col = col;
 127           cursor.row = row;
 128         }
 129         else {
 130           cursor.col = 0;
 131           cursor.row = 0;
 132         }
 133       }
 134       else if (escape_buf[0]=='[' && escape_buf[escape-2]=='A') {
 135         int up = 1;
 136         if (escape>3) sscanf(escape_buf,"[%dA",&up);
 137         if (cursor.row>0) cursor.row -= up;
 138       }
 139       else if (escape_buf[0]=='[' && escape_buf[escape-2]=='B') {
 140         int down = 1;
 141         if (escape>3) sscanf(escape_buf,"[%dB",&down);
 142         if (cursor.row<VIDEOTEXT_HEIGHT) cursor.row += down;
 143       }
 144       else if (escape_buf[0]=='[' && escape_buf[escape-2]=='C') {
 145         int left = 1;
 146         if (escape>3) sscanf(escape_buf,"[%dC",&left);
 147         if (cursor.col>0) cursor.col -= left;
 148       }
 149       else if (escape_buf[0]=='[' && escape_buf[escape-2]=='D') {
 150         int right = 1;
 151         if (escape>3) sscanf(escape_buf,"[%dD",&right);
 152         if (cursor.col<VIDEOTEXT_WIDTH) cursor.col += right;
 153       }
 154       else if (escape_buf[0]=='[' && (escape_buf[1]=='s' || escape_buf[1]=='7')) {
 155         memcpy(&saved_cursor,&cursor,sizeof(cursor));
 156       }
 157       else if (escape_buf[0]=='[' && (escape_buf[1]=='u' || escape_buf[1]=='8')) {
 158         memcpy(&cursor,&saved_cursor,sizeof(cursor));
 159       }
 160       else if (memcmp(escape_buf,"[K",2)==0) {
 161         memset(videomem+pos,0,(VIDEOTEXT_WIDTH-cursor.col+1)*2);
 162       }
 163       else if (memcmp(escape_buf,"[1K",3)==0) {
 164         memset(videomem+VIDEOTEXT_WIDTH*cursor.col,0,cursor.row*2);
 165       }
 166       else if (memcmp(escape_buf,"[2K",3)==0) {
 167         memset(videomem+VIDEOTEXT_WIDTH*cursor.col,0,VIDEOTEXT_WIDTH);
 168       }
 169       else if (memcmp(escape_buf,"[J",2)==0) {
 170         memset(videomem+VIDEOTEXT_WIDTH*cursor.col,0,(VIDEOTEXT_HEIGHT-cursor.row)*VIDEOTEXT_WIDTH*2);
 171       }
 172       else if (memcmp(escape_buf,"[1J",3)==0) {
 173         memset(videomem,0,cursor.row*VIDEOTEXT_WIDTH*2);
 174       }
 175       else if (memcmp(escape_buf,"[2J",3)==0) {
 176         clearscreen();
 177       }
 178       escape = 0;
 179     }
 180   }
 181   else if (chr=='\a') bell(settings.bell_freq,settings.bell_dur);
 182   else if (chr=='\b') cursor.col = (cursor.col-1>0)?(cursor.col-1):0;
 183   else if (chr=='\t') cursor.col = cursor.col+5;
 184   else if (chr=='\n') {
 185     cursor.row++;
 186     cursor.col = VIDEOTEXT_STDCOL;
 187   }
 188   else if (chr=='\f') clearscreen();
 189   else if (chr=='\r') cursor.col = VIDEOTEXT_STDCOL;
 190   else if (chr==0x1B) escape = 1;
 191   else if (chr>=' ') {
 192     *(videomem+pos) = (((uint16_t)settings.color)<<8)|chr;
 193     cursor.col++;
 194   }
 195
 196   if (cursor.col>=VIDEOTEXT_WIDTH) {
 197     cursor.col = cursor.col-VIDEOTEXT_WIDTH;
 198     cursor.row++;
 199   }
 200   while (cursor.row>=VIDEOTEXT_HEIGHT) {
 201     memcpy(videomem,videomem+VIDEOTEXT_WIDTH,VIDEOTEXT_SIZE-VIDEOTEXT_WIDTH*2);
 202     memset(videomem+VIDEOTEXT_WIDTH*(VIDEOTEXT_HEIGHT-1),0,VIDEOTEXT_WIDTH*2);
 203     cursor.row--;
 204   }
 205
 206   update_hwcursor();
 207
 208   return 1;
 209 }
 210
 211 /**
 212  * Writes characters to screen
 213  *  @param buffer Chars to write to screen
 214  *  @param count How many bytes to write to screen
 215  *  @param dev Device to write to
 216  *  @return How many bytes written
 217  */
 218 ssize_t onwrite(devfs_dev_t *dev,void *buffer,size_t count,off_t offset) {
 219   int i;
 220   int w = 0;
 221   for (i=0;i<count;i++) w += printchar(((char*)buffer)[i]);
 222   return w;
 223 }
 224
 225 /**
 226  * Initializes screen driver
 227  *  @return 0=success; -1=failure
 228  */
 229 int init_screen() {
 230   videomem = mem_getvga();
 231   if (videomem==NULL) return -1;
 232   memset(&saved_cursor,0,sizeof(saved_cursor));
 233   default_settings();
 234   clearscreen();
 235   return 0;
 236 }