refactor out panic

[netwatch.git] / grubload / multiboot_c.c

diff --git a/grubload/multiboot_c.c b/grubload/multiboot_c.c
index 50aca06e665d2e2abb9a5f13fa845640cd9e45ac..890a003471db280f15a6941821a9d2c04e81b265 100644 (file)
--- a/grubload/multiboot_c.c
+++ b/grubload/multiboot_c.c
@@ -31,9 +31,17 @@ struct info_section
        void (*firstrun)();
 };
 
-void c_start(unsigned int magic, struct mb_info *info)
+void panic(const char *msg)
 {
-       struct mod_info *mods = info->mods;
+       puts("PANIC: ");
+       puts(msg);
+       puts("\nSystem halted\n");
+       while(1) asm("hlt");
+}
+
+void c_start(unsigned int magic, struct mb_info *mbinfo)
+{
+       struct mod_info *mods = mbinfo->mods;
        unsigned short *grubptr = (unsigned short *)0x7CFE;
        unsigned char smramc;
        int i;
@@ -44,12 +52,9 @@ void c_start(unsigned int magic, struct mb_info *info)
        puts("NetWatch loader\n");
        
        if (magic != 0x2BADB002)
-       {
-               puts("Bootloader was not multiboot compliant; cannot continue.\n");
-               while(1) asm("hlt");
-       }
+               panic("Bootloader was not multiboot compliant; cannot continue.");
        
-       for (i = 0; i < info->mod_cnt; i++)
+       for (i = 0; i < mbinfo->mod_cnt; i++)
        {
                puts("Module found:\n");
                puts("  Start: "); puthex(mods[i].mod_start); puts("\n");
@@ -57,11 +62,8 @@ void c_start(unsigned int magic, struct mb_info *info)
                puts("  Name: "); puts(mods[i].mod_string); puts("\n");
        }
 
-       if (info->mod_cnt != 1)
-       {
-               puts("Expected exactly one module; cannot continue.\n");
-               while(1) asm("hlt");
-       }
+       if (mbinfo->mod_cnt != 1)
+               panic("Expected exactly one module; cannot continue.");
 
        puts("Current USB state is: "); puthex(pci_read16(0, 31, 2, 0xC0)); puts(" "); puthex(pci_read16(0, 31, 4, 0xC0)); puts("\n");
        puts("Current SMI state is: "); puthex(inl(0x830)); puts("\n");
@@ -80,25 +82,20 @@ void c_start(unsigned int magic, struct mb_info *info)
        smram_state_t old_smramc = smram_save_state();
 
        if (smram_aseg_set_state(SMRAM_ASEG_OPEN) != 0)
+               panic("Opening SMRAM failed; cannot load ELF.");
+
+       load_elf(mods[0].mod_start, mods[0].mod_end - mods[0].mod_start);
+
+       struct info_section * info = (struct info_section *)0x10000;
+       if (info->signature != INFO_SIGNATURE)
        {
-               puts("Opening SMRAM failed; cannot load ELF.\n");
-       }
-       else
-       {
-               load_elf(mods[0].mod_start, mods[0].mod_end - mods[0].mod_start);
-
-               struct info_section * info = (struct info_section *)0x10000;
-               if (info->signature != INFO_SIGNATURE)
-               {
-                       smram_restore_state(old_smramc);
-                       puts("Info section signature mismatch.\n");
-               }
-               else {
-                       info->firstrun();
-                       smram_restore_state(old_smramc);
-               }
+               smram_restore_state(old_smramc);                /* Restore so that video ram is touchable again. */
+               panic("Info section signature mismatch.");
        }
 
+       info->firstrun();
+       smram_restore_state(old_smramc);
+
        puts("Waiting for a bit before returning to real mode...");
        for (i=0; i<0x500000; i++)
        {