kern
annotate src/term.c @ 22:7ece008f09c5
writing the vm
| author | John Tsiombikas <nuclear@member.fsf.org> |
|---|---|
| date | Sun, 03 Apr 2011 18:42:19 +0300 |
| parents | 86781ef20689 |
| children | 06172322fb76 |
| rev | line source |
|---|---|
| nuclear@4 | 1 #include <ctype.h> |
| nuclear@1 | 2 #include "term.h" |
| nuclear@1 | 3 #include "vid.h" |
| nuclear@1 | 4 |
| nuclear@2 | 5 static int bg, fg = LTGRAY; |
| nuclear@1 | 6 static int cursor_x, cursor_y; |
| nuclear@1 | 7 |
| nuclear@2 | 8 /* sets the active text color and returns previous value */ |
| nuclear@2 | 9 int set_text_color(int c) |
| nuclear@1 | 10 { |
| nuclear@2 | 11 int prev = fg; |
| nuclear@2 | 12 |
| nuclear@1 | 13 if(c >= 0 && c < 16) { |
| nuclear@1 | 14 fg = c; |
| nuclear@1 | 15 } |
| nuclear@2 | 16 return prev; |
| nuclear@1 | 17 } |
| nuclear@1 | 18 |
| nuclear@2 | 19 /* sets the active background color and returns the current value */ |
| nuclear@2 | 20 int set_back_color(int c) |
| nuclear@1 | 21 { |
| nuclear@2 | 22 int prev = bg; |
| nuclear@2 | 23 |
| nuclear@1 | 24 if(c >= 0 && c < 16) { |
| nuclear@1 | 25 bg = c; |
| nuclear@1 | 26 } |
| nuclear@2 | 27 return prev; |
| nuclear@1 | 28 } |
| nuclear@1 | 29 |
| nuclear@2 | 30 /* output a single character, handles formatting, cursor advancement |
| nuclear@2 | 31 * and scrolling the screen when we reach the bottom. |
| nuclear@2 | 32 * TODO make visible cursor actually move. |
| nuclear@2 | 33 */ |
| nuclear@1 | 34 int putchar(int c) |
| nuclear@1 | 35 { |
| nuclear@1 | 36 switch(c) { |
| nuclear@1 | 37 case '\n': |
| nuclear@1 | 38 cursor_y++; |
| nuclear@1 | 39 |
| nuclear@1 | 40 case '\r': |
| nuclear@1 | 41 cursor_x = 0; |
| nuclear@1 | 42 break; |
| nuclear@1 | 43 |
| nuclear@1 | 44 case '\b': |
| nuclear@1 | 45 cursor_x--; |
| nuclear@1 | 46 set_char(' ', cursor_x, cursor_y, fg, bg); |
| nuclear@1 | 47 break; |
| nuclear@1 | 48 |
| nuclear@1 | 49 case '\t': |
| nuclear@1 | 50 cursor_x = ((cursor_x >> 3) + 1) << 3; |
| nuclear@1 | 51 break; |
| nuclear@1 | 52 |
| nuclear@1 | 53 default: |
| nuclear@2 | 54 if(isprint(c)) { |
| nuclear@2 | 55 set_char(c, cursor_x, cursor_y, fg, bg); |
| nuclear@2 | 56 if(++cursor_x >= WIDTH) { |
| nuclear@2 | 57 cursor_x = 0; |
| nuclear@2 | 58 cursor_y++; |
| nuclear@2 | 59 } |
| nuclear@1 | 60 } |
| nuclear@1 | 61 } |
| nuclear@1 | 62 |
| nuclear@1 | 63 if(cursor_y >= HEIGHT) { |
| nuclear@1 | 64 scroll_scr(); |
| nuclear@1 | 65 cursor_y--; |
| nuclear@1 | 66 } |
| nuclear@2 | 67 |
| nuclear@2 | 68 set_cursor(cursor_x, cursor_y); |
| nuclear@1 | 69 return c; |
| nuclear@1 | 70 } |