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4.3.1 multiboot.h

This is the source code in the file multiboot.h:

     /* multiboot.h - Multiboot header file. */
     /* Copyright (C) 1999,2003,2007,2008,2009  Free Software Foundation, Inc.
      *
      *  Permission is hereby granted, free of charge, to any person obtaining a copy
      *  of this software and associated documentation files (the "Software"), to
      *  deal in the Software without restriction, including without limitation the
      *  rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
      *  sell copies of the Software, and to permit persons to whom the Software is
      *  furnished to do so, subject to the following conditions:
      *
      *  The above copyright notice and this permission notice shall be included in
      *  all copies or substantial portions of the Software.
      *
      *  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
      *  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
      *  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL ANY
      *  DEVELOPER OR DISTRIBUTOR BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
      *  WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR
      *  IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
      */
     
     #ifndef MULTIBOOT_HEADER
     #define MULTIBOOT_HEADER 1
     
     /* How many bytes from the start of the file we search for the header. */
     #define MULTIBOOT_SEARCH                        8192
     
     /* The magic field should contain this. */
     #define MULTIBOOT_HEADER_MAGIC                  0x1BADB002
     
     /* This should be in %eax. */
     #define MULTIBOOT_BOOTLOADER_MAGIC              0x2BADB002
     
     /* The bits in the required part of flags field we don't support. */
     #define MULTIBOOT_UNSUPPORTED                   0x0000fffc
     
     /* Alignment of multiboot modules. */
     #define MULTIBOOT_MOD_ALIGN                     0x00001000
     
     /* Alignment of the multiboot info structure. */
     #define MULTIBOOT_INFO_ALIGN                    0x00000004
     
     /* Flags set in the 'flags' member of the multiboot header. */
     
     /* Align all boot modules on i386 page (4KB) boundaries. */
     #define MULTIBOOT_PAGE_ALIGN                    0x00000001
     
     /* Must pass memory information to OS. */
     #define MULTIBOOT_MEMORY_INFO                   0x00000002
     
     /* Must pass video information to OS. */
     #define MULTIBOOT_VIDEO_MODE                    0x00000004
     
     /* This flag indicates the use of the address fields in the header. */
     #define MULTIBOOT_AOUT_KLUDGE                   0x00010000
     
     /* Flags to be set in the 'flags' member of the multiboot info structure. */
     
     /* is there basic lower/upper memory information? */
     #define MULTIBOOT_INFO_MEMORY                   0x00000001
     /* is there a boot device set? */
     #define MULTIBOOT_INFO_BOOTDEV                  0x00000002
     /* is the command-line defined? */
     #define MULTIBOOT_INFO_CMDLINE                  0x00000004
     /* are there modules to do something with? */
     #define MULTIBOOT_INFO_MODS                     0x00000008
     
     /* These next two are mutually exclusive */
     
     /* is there a symbol table loaded? */
     #define MULTIBOOT_INFO_AOUT_SYMS                0x00000010
     /* is there an ELF section header table? */
     #define MULTIBOOT_INFO_ELF_SHDR                 0X00000020
     
     /* is there a full memory map? */
     #define MULTIBOOT_INFO_MEM_MAP                  0x00000040
     
     /* Is there drive info? */
     #define MULTIBOOT_INFO_DRIVE_INFO               0x00000080
     
     /* Is there a config table? */
     #define MULTIBOOT_INFO_CONFIG_TABLE             0x00000100
     
     /* Is there a boot loader name? */
     #define MULTIBOOT_INFO_BOOT_LOADER_NAME         0x00000200
     
     /* Is there a APM table? */
     #define MULTIBOOT_INFO_APM_TABLE                0x00000400
     
     /* Is there video information? */
     #define MULTIBOOT_INFO_VIDEO_INFO               0x00000800
     
     #ifndef ASM_FILE
     
     typedef unsigned short          multiboot_uint16_t;
     typedef unsigned int            multiboot_uint32_t;
     typedef unsigned long long      multiboot_uint64_t;
     
     struct multiboot_header
     {
       /* Must be MULTIBOOT_MAGIC - see above. */
       multiboot_uint32_t magic;
     
       /* Feature flags. */
       multiboot_uint32_t flags;
     
       /* The above fields plus this one must equal 0 mod 2^32. */
       multiboot_uint32_t checksum;
     
       /* These are only valid if MULTIBOOT_AOUT_KLUDGE is set. */
       multiboot_uint32_t header_addr;
       multiboot_uint32_t load_addr;
       multiboot_uint32_t load_end_addr;
       multiboot_uint32_t bss_end_addr;
       multiboot_uint32_t entry_addr;
     
       /* These are only valid if MULTIBOOT_VIDEO_MODE is set. */
       multiboot_uint32_t mode_type;
       multiboot_uint32_t width;
       multiboot_uint32_t height;
       multiboot_uint32_t depth;
     };
     
     /* The symbol table for a.out. */
     struct multiboot_aout_symbol_table
     {
       multiboot_uint32_t tabsize;
       multiboot_uint32_t strsize;
       multiboot_uint32_t addr;
       multiboot_uint32_t reserved;
     };
     typedef struct multiboot_aout_symbol_table multiboot_aout_symbol_table_t;
     
     /* The section header table for ELF. */
     struct multiboot_elf_section_header_table
     {
       multiboot_uint32_t num;
       multiboot_uint32_t size;
       multiboot_uint32_t addr;
       multiboot_uint32_t shndx;
     };
     typedef struct multiboot_elf_section_header_table multiboot_elf_section_header_table_t;
     
     struct multiboot_info
     {
       /* Multiboot info version number */
       multiboot_uint32_t flags;
     
       /* Available memory from BIOS */
       multiboot_uint32_t mem_lower;
       multiboot_uint32_t mem_upper;
     
       /* "root" partition */
       multiboot_uint32_t boot_device;
     
       /* Kernel command line */
       multiboot_uint32_t cmdline;
     
       /* Boot-Module list */
       multiboot_uint32_t mods_count;
       multiboot_uint32_t mods_addr;
     
       union
       {
         multiboot_aout_symbol_table_t aout_sym;
         multiboot_elf_section_header_table_t elf_sec;
       } u;
     
       /* Memory Mapping buffer */
       multiboot_uint32_t mmap_length;
       multiboot_uint32_t mmap_addr;
     
       /* Drive Info buffer */
       multiboot_uint32_t drives_length;
       multiboot_uint32_t drives_addr;
     
       /* ROM configuration table */
       multiboot_uint32_t config_table;
     
       /* Boot Loader Name */
       multiboot_uint32_t boot_loader_name;
     
       /* APM table */
       multiboot_uint32_t apm_table;
     
       /* Video */
       multiboot_uint32_t vbe_control_info;
       multiboot_uint32_t vbe_mode_info;
       multiboot_uint16_t vbe_mode;
       multiboot_uint16_t vbe_interface_seg;
       multiboot_uint16_t vbe_interface_off;
       multiboot_uint16_t vbe_interface_len;
     };
     typedef struct multiboot_info multiboot_info_t;
     
     struct multiboot_mmap_entry
     {
       multiboot_uint32_t size;
       multiboot_uint64_t addr;
       multiboot_uint64_t len;
     #define MULTIBOOT_MEMORY_AVAILABLE              1
     #define MULTIBOOT_MEMORY_RESERVED               2
       multiboot_uint32_t type;
     } __attribute__((packed));
     typedef struct multiboot_mmap_entry multiboot_memory_map_t;
     
     struct multiboot_mod_list
     {
       /* the memory used goes from bytes 'mod_start' to 'mod_end-1' inclusive */
       multiboot_uint32_t mod_start;
       multiboot_uint32_t mod_end;
     
       /* Module command line */
       multiboot_uint32_t cmdline;
     
       /* padding to take it to 16 bytes (must be zero) */
       multiboot_uint32_t pad;
     };
     typedef struct multiboot_mod_list multiboot_module_t;
     
     #endif /* ! ASM_FILE */
     
     #endif /* ! MULTIBOOT_HEADER */