Included tests. Fixed a bug. Better comments.

This commit is contained in:
L. Bradley LaBoon 2013-10-17 11:42:02 -04:00
parent 028ea93acf
commit e97e0b0cf5

View File

@ -7,7 +7,7 @@
#endif #endif
// Color constants // Color constants
enum vgaColor enum vga_color
{ {
COLOR_BLACK = 0, COLOR_BLACK = 0,
COLOR_BLUE = 1, COLOR_BLUE = 1,
@ -27,18 +27,21 @@ enum vgaColor
COLOR_WHITE = 15 COLOR_WHITE = 15
}; };
uint8_t makeColor(enum vgaColor fg, enum vgaColor bg) // Create a VGA color
uint8_t make_color(enum vga_color fg, enum vga_color bg)
{ {
return fg | bg << 4; return fg | bg << 4;
} }
uint16_t makeVGAEntry(char c, uint8_t color) // Create a VGA character
uint16_t make_vgaEntry(char c, uint8_t color)
{ {
uint16_t c16 = c; uint16_t c16 = c;
uint16_t color16 = color; uint16_t color16 = color;
return c16 | color16 << 8; return c16 | color16 << 8;
} }
// Calculate the length of a string
size_t strlen(const char *str) size_t strlen(const char *str)
{ {
size_t len = 0; size_t len = 0;
@ -50,76 +53,104 @@ size_t strlen(const char *str)
static const size_t VGA_WIDTH = 80; static const size_t VGA_WIDTH = 80;
static const size_t VGA_HEIGHT = 24; static const size_t VGA_HEIGHT = 24;
size_t terminalRow, terminalCol; size_t term_row, term_col;
uint8_t terminalColor; uint8_t term_color;
uint16_t *terminalBuf; uint16_t *term_buf;
void terminalInit() // Initialize the terminal
void term_init()
{ {
terminalRow = terminalCol = 0; term_row = term_col = 0;
terminalColor = makeColor(COLOR_LIGHT_GREY, COLOR_BLACK); term_color = make_color(COLOR_LIGHT_GREY, COLOR_BLACK);
terminalBuf = (uint16_t *) 0xB8000; term_buf = (uint16_t *) 0xB8000;
for (size_t y = 0; y < VGA_HEIGHT; y++) {
for (size_t x = 0; x < VGA_WIDTH; x++) {
const size_t index = y * VGA_WIDTH + x;
term_buf[index] = make_vgaEntry(' ', term_color);
}
}
}
// Set the terminal color
void term_setColor(uint8_t color)
{
term_color = color;
}
// Place a character in the buffer
void term_putEntryAt(char c, uint8_t color, size_t x, size_t y)
{
const size_t index = y * VGA_WIDTH + x;
term_buf[index] = make_vgaEntry(c, color);
}
// Scroll down 1 line
void term_scroll()
{
for (size_t y = 1; y < VGA_HEIGHT; y++) {
for (size_t x = 0; x < VGA_WIDTH; x++) {
const size_t index = y * VGA_WIDTH + x;
const size_t indexBelow = (y - 1) * VGA_WIDTH + x;
term_buf[indexBelow] = term_buf[index];
}
}
for (size_t x = 0; x < VGA_WIDTH; x++) { for (size_t x = 0; x < VGA_WIDTH; x++) {
for (size_t y = 0; y < VGA_HEIGHT; y++) { const size_t index = (VGA_HEIGHT - 1) * VGA_WIDTH + x;
const size_t index = y * VGA_WIDTH + x; term_buf[index] = ' ';
terminalBuf[index] = makeVGAEntry(' ', terminalColor);
}
} }
} }
void terminalSetColor(uint8_t color) // Write a character to the terminal
{ void term_putChar(char c)
terminalColor = color;
}
void terminalPutEntryAt(char c, uint8_t color, size_t x, size_t y)
{
const size_t index = y * VGA_WIDTH + x;
terminalBuf[index] = makeVGAEntry(c, color);
}
void terminalScroll()
{
for (size_t i = 1; i < VGA_HEIGHT; i++) {
for (size_t j = 0; j < VGA_WIDTH; j++) {
const size_t index = i * VGA_WIDTH + j;
const size_t indexBelow = (i - 1) * VGA_WIDTH + j;
terminalBuf[indexBelow] = terminalBuf[index];
}
}
for (size_t i = 0; i < VGA_WIDTH; i++) {
const size_t index = (VGA_HEIGHT - 1) * VGA_WIDTH + i;
terminalBuf[index] = ' ';
}
}
void terminalPutChar(char c)
{ {
if (c == '\n') if (c == '\n')
terminalCol = VGA_WIDTH - 1; term_col = VGA_WIDTH - 1;
else else
terminalPutEntryAt(c, terminalColor, terminalCol, terminalRow); term_putEntryAt(c, term_color, term_col, term_row);
if (terminalCol++ == VGA_WIDTH) { if (++term_col == VGA_WIDTH) {
terminalCol = 0; term_col = 0;
if (terminalRow++ == VGA_HEIGHT) { if (++term_row == VGA_HEIGHT) {
terminalRow--; term_row--;
terminalScroll(); term_scroll();
} }
} }
} }
void terminalWriteString(const char *data) // Write a string to the terminal
void term_writeStr(const char *data)
{ {
size_t dataLen = strlen(data); size_t dataLen = strlen(data);
for (size_t i = 0; i < dataLen; i++) for (size_t i = 0; i < dataLen; i++)
terminalPutChar(data[i]); term_putChar(data[i]);
} }
// Main kernel function
void brados_main() void brados_main()
{ {
terminalInit(); term_init();
terminalWriteString("Welcome to BRaDOS!\n");
// Test printing and newlines
term_writeStr("Welcome to BRaDOS!\n");
term_writeStr("written by L. Bradley LaBoon\n\n");
// Test line wrapping
term_writeStr("The Laughing Man always says: 'I thought what I'd do was I'd pretend I was one of those deaf mutes.'\n\n");
// Test colors
term_setColor(make_color(COLOR_BLACK, COLOR_WHITE));
term_writeStr("This text should be inverse.\n");
term_setColor(make_color(COLOR_LIGHT_BLUE, COLOR_GREEN));
term_writeStr("This text should be colorful.\n\n");
// Test scrolling
term_setColor(make_color(COLOR_LIGHT_GREY, COLOR_BLACK));
for (size_t i = 0; i < 20; i++) {
term_writeStr("Printing some lines.\n");
for (size_t j = 0; j < 100000000; j++);
}
term_writeStr("Done.");
} }