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-rw-r--r--docs/kernel.c284
1 files changed, 0 insertions, 284 deletions
diff --git a/docs/kernel.c b/docs/kernel.c
deleted file mode 100644
index af0def9..0000000
--- a/docs/kernel.c
+++ /dev/null
@@ -1,284 +0,0 @@
-/* kernel.c - the C part of the kernel */
-/* Copyright (C) 1999 Free Software Foundation, Inc.
-
- This program is free software; you can redistribute it and/or modify
- it under the terms of the GNU General Public License as published by
- the Free Software Foundation; either version 2 of the License, or
- (at your option) any later version.
-
- This program is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- GNU General Public License for more details.
-
- You should have received a copy of the GNU General Public License
- along with this program; if not, write to the Free Software
- Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
-
-#include <multiboot.h>
-
-/* Macros. */
-
-/* Check if the bit BIT in FLAGS is set. */
-#define CHECK_FLAG(flags,bit) ((flags) & (1 << (bit)))
-
-/* Some screen stuff. */
-/* The number of columns. */
-#define COLUMNS 80
-/* The number of lines. */
-#define LINES 24
-/* The attribute of an character. */
-#define ATTRIBUTE 7
-/* The video memory address. */
-#define VIDEO 0xB8000
-
-/* Variables. */
-/* Save the X position. */
-static int xpos;
-/* Save the Y position. */
-static int ypos;
-/* Point to the video memory. */
-static volatile unsigned char *video;
-
-/* Forward declarations. */
-void cmain (unsigned long magic, unsigned long addr);
-static void cls (void);
-static void itoa (char *buf, int base, int d);
-static void putchar (int c);
-void printf (const char *format, ...);
-
-/* Check if MAGIC is valid and print the Multiboot information structure
- pointed by ADDR. */
-void
-cmain (unsigned long magic, unsigned long addr)
-{
- multiboot_info_t *mbi;
-
- /* Clear the screen. */
- cls ();
-
- /* Am I booted by a Multiboot-compliant boot loader? */
- if (magic != MULTIBOOT_BOOTLOADER_MAGIC)
- {
- printf ("Invalid magic number: 0x%x\n", (unsigned) magic);
- return;
- }
-
- /* Set MBI to the address of the Multiboot information structure. */
- mbi = (multiboot_info_t *) addr;
-
- /* Print out the flags. */
- printf ("flags = 0x%x\n", (unsigned) mbi->flags);
-
- /* Are mem_* valid? */
- if (CHECK_FLAG (mbi->flags, 0))
- printf ("mem_lower = %uKB, mem_upper = %uKB\n",
- (unsigned) mbi->mem_lower, (unsigned) mbi->mem_upper);
-
- /* Is boot_device valid? */
- if (CHECK_FLAG (mbi->flags, 1))
- printf ("boot_device = 0x%x\n", (unsigned) mbi->boot_device);
-
- /* Is the command line passed? */
- if (CHECK_FLAG (mbi->flags, 2))
- printf ("cmdline = %s\n", (char *) mbi->cmdline);
-
- /* Are mods_* valid? */
- if (CHECK_FLAG (mbi->flags, 3))
- {
- module_t *mod;
- int i;
-
- printf ("mods_count = %d, mods_addr = 0x%x\n",
- (int) mbi->mods_count, (int) mbi->mods_addr);
- for (i = 0, mod = (module_t *) mbi->mods_addr;
- i < mbi->mods_count;
- i++, mod++)
- printf (" mod_start = 0x%x, mod_end = 0x%x, string = %s\n",
- (unsigned) mod->mod_start,
- (unsigned) mod->mod_end,
- (char *) mod->string);
- }
-
- /* Bits 4 and 5 are mutually exclusive! */
- if (CHECK_FLAG (mbi->flags, 4) && CHECK_FLAG (mbi->flags, 5))
- {
- printf ("Both bits 4 and 5 are set.\n");
- return;
- }
-
- /* Is the symbol table of a.out valid? */
- if (CHECK_FLAG (mbi->flags, 4))
- {
- aout_symbol_table_t *aout_sym = &(mbi->u.aout_sym);
-
- printf ("aout_symbol_table: tabsize = 0x%0x, "
- "strsize = 0x%x, addr = 0x%x\n",
- (unsigned) aout_sym->tabsize,
- (unsigned) aout_sym->strsize,
- (unsigned) aout_sym->addr);
- }
-
- /* Is the section header table of ELF valid? */
- if (CHECK_FLAG (mbi->flags, 5))
- {
- elf_section_header_table_t *elf_sec = &(mbi->u.elf_sec);
-
- printf ("elf_sec: num = %u, size = 0x%x,"
- " addr = 0x%x, shndx = 0x%x\n",
- (unsigned) elf_sec->num, (unsigned) elf_sec->size,
- (unsigned) elf_sec->addr, (unsigned) elf_sec->shndx);
- }
-
- /* Are mmap_* valid? */
- if (CHECK_FLAG (mbi->flags, 6))
- {
- memory_map_t *mmap;
-
- printf ("mmap_addr = 0x%x, mmap_length = 0x%x\n",
- (unsigned) mbi->mmap_addr, (unsigned) mbi->mmap_length);
- for (mmap = (memory_map_t *) mbi->mmap_addr;
- (unsigned long) mmap < mbi->mmap_addr + mbi->mmap_length;
- mmap = (memory_map_t *) ((unsigned long) mmap
- + mmap->size + sizeof (mmap->size)))
- printf (" size = 0x%x, base_addr = 0x%x%x,"
- " length = 0x%x%x, type = 0x%x\n",
- (unsigned) mmap->size,
- (unsigned) mmap->base_addr_high,
- (unsigned) mmap->base_addr_low,
- (unsigned) mmap->length_high,
- (unsigned) mmap->length_low,
- (unsigned) mmap->type);
- }
-}
-
-/* Clear the screen and initialize VIDEO, XPOS and YPOS. */
-static void
-cls (void)
-{
- int i;
-
- video = (unsigned char *) VIDEO;
-
- for (i = 0; i < COLUMNS * LINES * 2; i++)
- *(video + i) = 0;
-
- xpos = 0;
- ypos = 0;
-}
-
-/* Convert the integer D to a string and save the string in BUF. If
- BASE is equal to 'd', interpret that D is decimal, and if BASE is
- equal to 'x', interpret that D is hexadecimal. */
-static void
-itoa (char *buf, int base, int d)
-{
- char *p = buf;
- char *p1, *p2;
- unsigned long ud = d;
- int divisor = 10;
-
- /* If %d is specified and D is minus, put `-' in the head. */
- if (base == 'd' && d < 0)
- {
- *p++ = '-';
- buf++;
- ud = -d;
- }
- else if (base == 'x')
- divisor = 16;
-
- /* Divide UD by DIVISOR until UD == 0. */
- do
- {
- int remainder = ud % divisor;
-
- *p++ = (remainder < 10) ? remainder + '0' : remainder + 'a' - 10;
- }
- while (ud /= divisor);
-
- /* Terminate BUF. */
- *p = 0;
-
- /* Reverse BUF. */
- p1 = buf;
- p2 = p - 1;
- while (p1 < p2)
- {
- char tmp = *p1;
- *p1 = *p2;
- *p2 = tmp;
- p1++;
- p2--;
- }
-}
-
-/* Put the character C on the screen. */
-static void
-putchar (int c)
-{
- if (c == '\n' || c == '\r')
- {
- newline:
- xpos = 0;
- ypos++;
- if (ypos >= LINES)
- ypos = 0;
- return;
- }
-
- *(video + (xpos + ypos * COLUMNS) * 2) = c & 0xFF;
- *(video + (xpos + ypos * COLUMNS) * 2 + 1) = ATTRIBUTE;
-
- xpos++;
- if (xpos >= COLUMNS)
- goto newline;
-}
-
-/* Format a string and print it on the screen, just like the libc
- function printf. */
-void
-printf (const char *format, ...)
-{
- char **arg = (char **) &format;
- int c;
- char buf[20];
-
- arg++;
-
- while ((c = *format++) != 0)
- {
- if (c != '%')
- putchar (c);
- else
- {
- char *p;
-
- c = *format++;
- switch (c)
- {
- case 'd':
- case 'u':
- case 'x':
- itoa (buf, c, *((int *) arg++));
- p = buf;
- goto string;
- break;
-
- case 's':
- p = *arg++;
- if (! p)
- p = "(null)";
-
- string:
- while (*p)
- putchar (*p++);
- break;
-
- default:
- putchar (*((int *) arg++));
- break;
- }
- }
- }
-}
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