got multiboot info parsed!

1 files changed, 59 insertions, 34 deletions

diff --git a/src/kernel/main.c b/src/kernel/main.c
index 75edeec..ab8eb91 100644
--- a/src/kernel/main.c
+++ b/src/kernel/main.c
@@ -23,8 +23,6 @@ OF THIS SOFTWARE.
 #include "proc.h"
 #include <stdbool.h>
 
-extern uint32_t info_pointer;
-
 enum tag_type {
   BOOT_COMMAND     =  1,
   LOADER_NAME      =  2,
@@ -52,7 +50,6 @@ enum tag_type {
 struct tag_start {
   uint32_t type;
   uint32_t size;
-  uint8_t rest;
 } __attribute__ ((__packed__));
 
 struct boot_device_tag {
@@ -79,52 +76,68 @@ bool have_boot_device = false;
 bool have_mmap = false;
 
 enum error_codes {
-  NO_BOOT_DEVICE = 000000000000,
-  NO_MMAP        = 000000000001,
-  INSUFF_MEMORY  = 000000000002
+  NO_BOOT_DEVICE = 0x00000000,
+  NO_MMAP        = 0x00000001,
+  INSUFF_MEMORY  = 0x00000002
 };
 
-uint32_t main(void) {
-  for (uint32_t *i = (uint32_t *)VGA_BUFFER; i < (uint32_t *)0x000b8fa0; ++i)
-    *i = 0x70207020;
-
-  put_sz("Starting...\n");
-
-  uint32_t info_size = *(uint32_t *)info_pointer;
-  struct tag_start *tag_pointer = (struct tag_start *)(info_pointer + 2);
+struct tag_start *tag_pointer;
 
+uint32_t main(void) {
+  clear();
+
+  /*
+  uint32_t *debug_ptr = (uint32_t *)tag_pointer - 2;
+  uint32_t debug_size = *debug_ptr / 4;
+  for (uint32_t i = 0; i < debug_size; ++i) {
+    put_32_hex(debug_ptr[i]);
+    put_char(' ');
+  }
+  */
+
+  put_sz("Multiboot info:\n");
   while (tag_pointer->type) {
+    put_sz("  Tag type 0x");
+    put_32_hex(tag_pointer->type);
+    put_sz(" with size 0x");
+    put_32_hex(tag_pointer->size);
     switch (tag_pointer->type) {
 
     case BOOT_DEVICE:
-      boot_device = *(struct boot_device_tag *)&tag_pointer->rest;
+      boot_device = *(struct boot_device_tag *)(tag_pointer + 1);
       have_boot_device = true;
-      put_sz("Boot device: 0x");
+      put_sz(": boot device\n    BIOS code: ");
       put_32_hex(boot_device.bios_device);
       if (boot_device.partition != 0xffffffff) {
-        put_sz(", 0x");
+        put_sz("\n      Partition number: ");
         put_32_hex(boot_device.partition);
         if (boot_device.subpartition != 0xffffffff) {
-          put_sz(", 0x");
+          put_sz("\n      Subpartition number: ");
           put_32_hex(boot_device.subpartition);
+          put_char('\n');
         }
+        else
+          put_sz("\n    No subpartition\n");
       }
-      put_char('\n');
+      else
+        put_sz("\n    No partition\n");
       break;
 
     case MEMORY_MAP:
     {
-      struct mmap_tag_entry *tag = (struct mmap_tag_entry *)((uint32_t)&tag_pointer->rest + 8);
-      uint32_t size = *(uint32_t *)&tag_pointer->rest;
+      uint32_t size = *(uint32_t *)(tag_pointer + 1);
+      struct mmap_tag_entry *tag = (struct mmap_tag_entry *)(tag_pointer + 2);
+      struct mmap_tag_entry *end = (struct mmap_tag_entry *)((uint32_t)tag_pointer + tag_pointer->size);
       struct mmap_entry *entry = (struct mmap_entry *)tag;
       struct mmap_entry **last_next = &mmap_start;
       uint32_t usable = 0;
-      while (tag) {
+      put_sz(": memory map\n    Regions:\n");
+      while (tag != end) {
         if (!(tag->base & 0xffffffff00000000)) {
           entry->base = (uint32_t)tag->base;
           entry->length = (tag->base + tag->length - 1) & 0xffffffff00000000 ?
             1 + ~(uint32_t)tag->base : (uint32_t)tag->length;
-          put_sz("Memory: 0x");
+          put_sz("      0x");
           put_32_hex(entry->base);
           put_sz(" - 0x");
           put_32_hex(entry->base + entry->length - 1);
@@ -147,7 +160,9 @@ uint32_t main(void) {
             entry->whose = HARDWARE;
             break;
           default:
-            put_sz(": unrecognized type, assuming hardware use\n");
+            put_sz(": hardware use (0x");
+            put_32_hex(tag->type);
+            put_sz(")\n");
             entry->whose = HARDWARE;
             break;
           }
@@ -158,13 +173,13 @@ uint32_t main(void) {
         tag = (struct mmap_tag_entry *)((uint32_t)tag + size);
       }
 
-      put_sz("Total usable memory: 0x");
+      put_sz("    Total usable memory: ");
       put_32_hex(usable);
       put_char('\n');
 
-      bool clean;
+      bool dirty;
       do {
-        clean = true;
+        dirty = false;
         for (struct mmap_entry *current = mmap_start; current; current = current->next)
           for (struct mmap_entry *against = mmap_start; against; against = against->next)
             if ((current->base + current->length == against->base) &&
@@ -177,27 +192,29 @@ uint32_t main(void) {
                   ;
                 current->next = against->next;
               }
-              clean = false;
+              dirty = true;
             }
-      } while (clean);
+      } while (dirty);
 
       have_mmap = true;
       break;
     }
     default:
-      put_sz("Ignoring multiboot tag 0x");
-      put_32_hex(tag_pointer->type);
-      put_char('\n');
+      put_sz(": ignoring\n");
 
     }
-    tag_pointer = (struct tag_start *)((uint32_t)tag_pointer + tag_pointer->size);
-  };
+    tag_pointer = (struct tag_start *)(((uint32_t)tag_pointer + tag_pointer->size - 1 & 0xfffffff8) + 8);
+  }
 
   if (!have_boot_device)
     return NO_BOOT_DEVICE;
   if (!have_mmap)
     return NO_MMAP;
 
+  put_sz("Halting.");
+  while (1)
+    ;
+
   if (!((proc_table = allocate_block(sizeof(struct proc_info) * 65536, KERNEL)) &&
         (file_table = allocate_block(sizeof(struct file_info) * 65536, KERNEL))))
     return INSUFF_MEMORY;
@@ -206,3 +223,11 @@ uint32_t main(void) {
   while (1)
     put_sz("|\b/\b-\b\\\b");
 }
+
+void wrapped_main(void) {
+  uint32_t error = main();
+  set_color(0x47);
+  clear();
+  put_sz("Error: 0x");
+  put_32_hex(error);
+}