Started work on memory map, added printf features

Printf now has long (64-bit), char, and % literal support. I haven't written
anything specific for shorts yet but if you cast it to an int on the way
in, it'll work anyway, so whatever.

include/io.h

@@ -19,8 +19,8 @@ extern char_writer_t* default_output;
 int putc(char_writer_t*, char);
 int print(char_writer_t*, const char*);
 int println(char_writer_t*, const char*);
-int printhex(char_writer_t*, uint32_t);
+int printhex(char_writer_t*, uint64_t);
-int prindec(char_writer_t*, uint32_t out);
+int prindec(char_writer_t*, uint64_t out);
 int printf(char_writer_t*, const char* fmt, ...);
 
 #endif

include/kmultiboot.h

@@ -7,8 +7,15 @@
 #define KMULTIBOOT_H
 
 #include <stdint.h>
+typedef struct multiboot_mmap_entry {
+    uint32_t entry_size; //size of this struct entry
+    uint64_t addr; //physical location of memory
+    uint64_t mem_size; //size of the memory block
+    uint32_t type;
+} __attribute__((packed)) mb_mmap_entry_t;
 
-typedef struct {
+
+typedef struct mb_info_s {
     uint32_t flags;
     uint32_t mem_lower;
     uint32_t mem_upper;
@@ -16,13 +23,13 @@ typedef struct {
     uint32_t cmdline;
     uint32_t mods_count;
     uint32_t mods_addr;
+    uint32_t syms[4];
+    uint32_t mmap_length;
+    uint32_t mmap_addr;
 } mb_info_t;
 
-typedef struct multiboot_mmap_entry {
+
-    uint32_t ssize; //size of the entry
+extern uint8_t _kernel_start;
-    uint64_t addr; //physical location of memory
+extern uint8_t _kernel_end;
-    uint64_t msize;
-    uint32_t type;
-} __attribute__((packed)) mb_mmap_entry_t;
 
 #endif

include/kttools.h

@@ -21,6 +21,6 @@
  *  @return No return value
  *
  */
-void i_to_str(uint32_t num, char* buf, int size, int radix);
+void i_to_str(uint64_t num, char* buf, int size, int radix);
 
 #endif

linker.ld

@@ -5,9 +5,10 @@ SECTIONS
 {
     /*start me at 1Mb because below that is x86 essential stuff, which we dont want to be written on top of.*/
 	. = 1M;
+    
+    _kernel_start = .;
 
 	/* we're going to maintain 4K alignment - apparently useful for paging, and i'm not complaining about the lost space anyway. */
-
     /*our multiboot header from start.s - has to go at the beginning of the executable so the bootloader knows we're loadable.*/
 	/*executable section*/
 	.text BLOCK(4K) : ALIGN(4K)
@@ -37,4 +38,7 @@ SECTIONS
 		*(.bss)
         *(.idt)
 	}
+
+    _kernel_end = .;
+
 }

src/io.c

@@ -4,15 +4,21 @@
 
 char_writer_t* default_output = 0;
 
-int printhex(char_writer_t* writer, uint32_t out) {
+int printnum(char_writer_t* writer, int radix, uint64_t out) {
-    char buff[9];
+    char buff[65];
-    i_to_str(out, buff, 9, 0x10);
+    i_to_str(out, buff, 65, radix);
     return print(writer, buff);
 }
 
-int printdec(char_writer_t* writer, uint32_t out) {
+int printhex(char_writer_t* writer, uint64_t out) {
-    char buff[11];
+    char buff[17];
-    i_to_str(out, buff, 11, 10);
+    i_to_str(out, buff, 17, 0x10);
+    return print(writer, buff);
+}
+
+int printdec(char_writer_t* writer, uint64_t out) {
+    char buff[21];
+    i_to_str(out, buff, 21, 10);
     return print(writer, buff);
 }
 
@@ -48,23 +54,58 @@ int println(char_writer_t* writer, const char* out) {
  */
 
 int printf(char_writer_t* writer, const char* fmt, ...) {
+    //borrowed (stole) a lot of ideas for this from the linux implementation (thanks!)
     va_list args;
     va_start(args, fmt);
     int ret = 0;
+    uint64_t num = 0;
+    int radix = 9;
+    char qualifier = '\0';
     while(*fmt) {
         if(*fmt == '%') {
             fmt++;
+            if(*fmt == 'l') {
+                qualifier = *fmt;
+                fmt++;
+            }
             switch(*fmt) {
+                case '%':
+                    ret = putc(writer, '%');
+                    fmt++;
+                    continue;
+                case 'c':
+                    ret = putc(writer, va_arg(args, int));
+                    fmt++;
+                    continue;
+                case 's':
+                    ret = print(writer, va_arg(args, char*));
+                    fmt++;
+                    continue;
+                //Integer definitions.
                 case 'X':
                     ret = print(writer, "0x");
                 case 'x':    
-                    ret = printhex(writer, va_arg(args,uint32_t));
+                    radix = 0x10;
                     break;
-                case 'd':
+                case 'u':
-                    ret = printdec(writer, va_arg(args,uint32_t));
+                    radix = 10;
                     break;
-
+                case 'b':
+                    radix = 0b10;
+                    break;
+                     
             }
+            
+            if(qualifier == 'l'){ 
+                num = va_arg(args, uint64_t);
+                qualifier = 0;
+            }
+            else {
+                num = va_arg(args, unsigned int);
+            }
+
+            ret = printnum(writer, radix, num);
+
         } else {
             ret = putc(writer,*fmt);
         }

src/kttools.c

@@ -12,7 +12,7 @@
 
 
 
-void i_to_str(uint32_t num, char* buf, int size, int radix) {
+void i_to_str(uint64_t num, char* buf, int size, int radix) {
     //null terminate the string
     if(num == 0){
         buf[0] = '0';

src/main.c

@@ -35,10 +35,9 @@ void kern_main(uint32_t multiboot_magic, mb_info_t* multiboot_info)
     serial_init(&serial_ctx); 
 
     //AND OUR DEFAULT OUTPUT IS:
-    default_output = default_vga;
+    default_output = default_COM;
     
     printf(default_output, "Entry eax:%X\n", multiboot_magic);
-
     if(multiboot_magic != 0x2BADB002) {
         println(default_output, "Bootloader not multiboot1 compliant! Needed for mmap, etc. Can't work without it, kthxbye!");
         return;
@@ -47,5 +46,24 @@ void kern_main(uint32_t multiboot_magic, mb_info_t* multiboot_info)
     }
     printf(default_output, "MEM_LOWER:%X\n", multiboot_info->mem_lower);
     printf(default_output, "MEM_UPPER:%X\n", multiboot_info->mem_upper);
+    
+    //Let's get out memory map.
+
+    if(!(multiboot_info->flags & (1<<6))){
+        printf(default_output, "No mmap supplied by multiboot flags!");
+        return;
+    }
+
+    printf(default_output, "lol:%X", multiboot_info->flags);
+    int mmap_end = (uint32_t)multiboot_info->mmap_addr + multiboot_info->mmap_length;
+    
+    for(mb_mmap_entry_t* entry = (mb_mmap_entry_t*)multiboot_info->mmap_addr;
+        (int)entry < mmap_end;
+        entry = (mb_mmap_entry_t*)((int)entry + entry->entry_size + sizeof(entry->entry_size))) {
+        
+        printf(default_output,"__MMAP_ENTRY__:\nSTART_ADDR:%X\nSIZE:%X\nTYPE:%u\n",(uint32_t)entry->addr, (uint32_t)entry->mem_size, entry->type);
+    
+    }
+
 }
 

src/multiboot.s

@@ -1,7 +1,7 @@
 ;multiboot for GRUB to boot it. Ideally stage01_bootloader will be able to support the multiboot standard.
 ;regardless of who's doing it, we have to set the required stuff
 MB_MAGIC equ 0x1BADB002          ; bytes that bootloader will use to find this place
-MB_FLAGS equ (1 << 0) | (1 << 1) ; flags request the following from the bootloader: maintain page boundaries + provide a memory map
+MB_FLAGS equ (1 << 0) | (1 << 1); flags request the following from the bootloader: maintain page boundaries + provide a memory map
 MB_CHECKSUM equ (0 - (MB_MAGIC + MB_FLAGS)) ; Fails if checksum doesn't pass. Kind of arbitrary, but required.