elf.h

系统启动时检测内存状况的软件C代码

/* DT_* entries which fall between DT_VALRNGHI & DT_VALRNGLO use the
 Dyn.d_un.d_val field of the Elf*_Dyn structure.  This follows Sun's
 approach.  */
#define DT_VALRNGLO	0x6ffffd00
#define DT_GNU_PRELINKED 0x6ffffdf5	/* Prelinking timestamp */
#define DT_GNU_CONFLICTSZ 0x6ffffdf6	/* Size of conflict section */
#define DT_GNU_LIBLISTSZ 0x6ffffdf7	/* Size of library list */
#define DT_CHECKSUM	0x6ffffdf8
#define DT_PLTPADSZ	0x6ffffdf9
#define DT_MOVEENT	0x6ffffdfa
#define DT_MOVESZ	0x6ffffdfb
#define DT_FEATURE_1	0x6ffffdfc	/* Feature selection (DTF_*).  */
#define DT_POSFLAG_1	0x6ffffdfd	/* Flags for DT_* entries, effecting
					   the following DT_* entry.  */
#define DT_SYMINSZ	0x6ffffdfe	/* Size of syminfo table (in bytes) */
#define DT_SYMINENT	0x6ffffdff	/* Entry size of syminfo */
#define DT_VALRNGHI	0x6ffffdff
#define DT_VALTAGIDX(tag)	(DT_VALRNGHI - (tag))	/* Reverse order! */
#define DT_VALNUM 12

/* DT_* entries which fall between DT_ADDRRNGHI & DT_ADDRRNGLO use the
 Dyn.d_un.d_ptr field of the Elf*_Dyn structure.

 If any adjustment is made to the ELF object after it has been
 built these entries will need to be adjusted.  */
#define DT_ADDRRNGLO	0x6ffffe00
#define DT_GNU_CONFLICT	0x6ffffef8	/* Start of conflict section */
#define DT_GNU_LIBLIST	0x6ffffef9	/* Library list */
#define DT_CONFIG	0x6ffffefa	/* Configuration information.  */
#define DT_DEPAUDIT	0x6ffffefb	/* Dependency auditing.  */
#define DT_AUDIT	0x6ffffefc	/* Object auditing.  */
#define	DT_PLTPAD	0x6ffffefd	/* PLT padding.  */
#define	DT_MOVETAB	0x6ffffefe	/* Move table.  */
#define DT_SYMINFO	0x6ffffeff	/* Syminfo table.  */
#define DT_ADDRRNGHI	0x6ffffeff
#define DT_ADDRTAGIDX(tag)	(DT_ADDRRNGHI - (tag))	/* Reverse order! */
#define DT_ADDRNUM 10

/* The versioning entry types.  The next are defined as part of the
 GNU extension.  */
#define DT_VERSYM	0x6ffffff0

#define DT_RELACOUNT	0x6ffffff9
#define DT_RELCOUNT	0x6ffffffa

/* These were chosen by Sun.  */
#define DT_FLAGS_1	0x6ffffffb	/* State flags, see DF_1_* below.  */
#define	DT_VERDEF	0x6ffffffc	/* Address of version definition
					   table */
#define	DT_VERDEFNUM	0x6ffffffd	/* Number of version definitions */
#define	DT_VERNEED	0x6ffffffe	/* Address of table with needed
					   versions */
#define	DT_VERNEEDNUM	0x6fffffff	/* Number of needed versions */
#define DT_VERSIONTAGIDX(tag)	(DT_VERNEEDNUM - (tag))	/* Reverse order! */
#define DT_VERSIONTAGNUM 16

/* Sun added these machine-independent extensions in the "processor-specific"
 range.  Be compatible.  */
#define DT_AUXILIARY    0x7ffffffd      /* Shared object to load before self */
#define DT_FILTER       0x7fffffff      /* Shared object to get values from */
#define DT_EXTRATAGIDX(tag)	((Elf32_Word)-((Elf32_Sword) (tag) <<1>>1)-1)
#define DT_EXTRANUM	3

/* Values of `d_un.d_val' in the DT_FLAGS entry.  */
#define DF_ORIGIN	0x00000001	/* Object may use DF_ORIGIN */
#define DF_SYMBOLIC	0x00000002	/* Symbol resolutions starts here */
#define DF_TEXTREL	0x00000004	/* Object contains text relocations */
#define DF_BIND_NOW	0x00000008	/* No lazy binding for this object */
#define DF_STATIC_TLS	0x00000010	/* Module uses the static TLS model */

/* State flags selectable in the `d_un.d_val' element of the DT_FLAGS_1
 entry in the dynamic section.  */
#define DF_1_NOW	0x00000001	/* Set RTLD_NOW for this object.  */
#define DF_1_GLOBAL	0x00000002	/* Set RTLD_GLOBAL for this object.  */
#define DF_1_GROUP	0x00000004	/* Set RTLD_GROUP for this object.  */
#define DF_1_NODELETE	0x00000008	/* Set RTLD_NODELETE for this object.*/
#define DF_1_LOADFLTR	0x00000010	/* Trigger filtee loading at runtime.*/
#define DF_1_INITFIRST	0x00000020	/* Set RTLD_INITFIRST for this object*/
#define DF_1_NOOPEN	0x00000040	/* Set RTLD_NOOPEN for this object.  */
#define DF_1_ORIGIN	0x00000080	/* $ORIGIN must be handled.  */
#define DF_1_DIRECT	0x00000100	/* Direct binding enabled.  */
#define DF_1_TRANS	0x00000200
#define DF_1_INTERPOSE	0x00000400	/* Object is used to interpose.  */
#define DF_1_NODEFLIB	0x00000800	/* Ignore default lib search path.  */
#define DF_1_NODUMP	0x00001000	/* Object can't be dldump'ed.  */
#define DF_1_CONFALT	0x00002000	/* Configuration alternative created.*/
#define DF_1_ENDFILTEE	0x00004000	/* Filtee terminates filters search. */
#define	DF_1_DISPRELDNE	0x00008000	/* Disp reloc applied at build time. */
#define	DF_1_DISPRELPND	0x00010000	/* Disp reloc applied at run-time.  */

/* Flags for the feature selection in DT_FEATURE_1.  */
#define DTF_1_PARINIT	0x00000001
#define DTF_1_CONFEXP	0x00000002

/* Flags in the DT_POSFLAG_1 entry effecting only the next DT_* entry.  */
#define DF_P1_LAZYLOAD	0x00000001	/* Lazyload following object.  */
#define DF_P1_GROUPPERM	0x00000002	/* Symbols from next object are not
					   generally available.  */

/* Special section indices.  */

#define SHN_UNDEF	0		/* Undefined section */
#define SHN_LORESERVE	0xff00		/* Start of reserved indices */
#define SHN_LOPROC	0xff00		/* Start of processor-specific */
#define SHN_HIPROC	0xff1f		/* End of processor-specific */
#define SHN_LOOS	0xff20		/* Start of OS-specific */
#define SHN_HIOS	0xff3f		/* End of OS-specific */
#define SHN_ABS		0xfff1		/* Associated symbol is absolute */
#define SHN_COMMON	0xfff2		/* Associated symbol is common */
#define SHN_XINDEX	0xffff		/* Index is in extra table.  */
#define SHN_HIRESERVE	0xffff		/* End of reserved indices */

/* Legal values for sh_type (section type).  */

#define SHT_NULL	  0		/* Section header table entry unused */
#define SHT_PROGBITS	  1		/* Program data */
#define SHT_SYMTAB	  2		/* Symbol table */
#define SHT_STRTAB	  3		/* String table */
#define SHT_RELA	  4		/* Relocation entries with addends */
#define SHT_HASH	  5		/* Symbol hash table */
#define SHT_DYNAMIC	  6		/* Dynamic linking information */
#define SHT_NOTE	  7		/* Notes */
#define SHT_NOBITS	  8		/* Program space with no data (bss) */
#define SHT_REL		  9		/* Relocation entries, no addends */
#define SHT_SHLIB	  10		/* Reserved */
#define SHT_DYNSYM	  11		/* Dynamic linker symbol table */
#define SHT_INIT_ARRAY	  14		/* Array of constructors */
#define SHT_FINI_ARRAY	  15		/* Array of destructors */
#define SHT_PREINIT_ARRAY 16		/* Array of pre-constructors */
#define SHT_GROUP	  17		/* Section group */
#define SHT_SYMTAB_SHNDX  18		/* Extended section indeces */
#define	SHT_NUM		  19		/* Number of defined types.  */
#define SHT_LOOS	  0x60000000	/* Start OS-specific */
#define SHT_GNU_LIBLIST	  0x6ffffff7	/* Prelink library list */
#define SHT_CHECKSUM	  0x6ffffff8	/* Checksum for DSO content.  */
#define SHT_LOSUNW	  0x6ffffffa	/* Sun-specific low bound.  */
#define SHT_SUNW_move	  0x6ffffffa
#define SHT_SUNW_COMDAT   0x6ffffffb
#define SHT_SUNW_syminfo  0x6ffffffc
#define SHT_GNU_verdef	  0x6ffffffd	/* Version definition section.  */
#define SHT_GNU_verneed	  0x6ffffffe	/* Version needs section.  */
#define SHT_GNU_versym	  0x6fffffff	/* Version symbol table.  */
#define SHT_HISUNW	  0x6fffffff	/* Sun-specific high bound.  */
#define SHT_HIOS	  0x6fffffff	/* End OS-specific type */
#define SHT_LOPROC	  0x70000000	/* Start of processor-specific */
#define SHT_HIPROC	  0x7fffffff	/* End of processor-specific */
#define SHT_LOUSER	  0x80000000	/* Start of application-specific */
#define SHT_HIUSER	  0x8fffffff	/* End of application-specific */

/* Legal values for sh_flags (section flags).  */

#define SHF_WRITE	     (1 << 0)	/* Writable */
#define SHF_ALLOC	     (1 << 1)	/* Occupies memory during execution */
#define SHF_EXECINSTR	     (1 << 2)	/* Executable */
#define SHF_MERGE	     (1 << 4)	/* Might be merged */
#define SHF_STRINGS	     (1 << 5)	/* Contains nul-terminated strings */
#define SHF_INFO_LINK	     (1 << 6)	/* `sh_info' contains SHT index */
#define SHF_LINK_ORDER	     (1 << 7)	/* Preserve order after combining */
#define SHF_OS_NONCONFORMING (1 << 8)	/* Non-standard OS specific handling
					   required */
#define SHF_GROUP	     (1 << 9)	/* Section is member of a group.  */
#define SHF_TLS		     (1 << 10)	/* Section hold thread-local data.  */
#define SHF_MASKOS	     0x0ff00000	/* OS-specific.  */
#define SHF_MASKPROC	     0xf0000000	/* Processor-specific */

/* Section group handling.  */
#define GRP_COMDAT	0x1		/* Mark group as COMDAT.  */

/* Symbol table entry.  */

typedef struct
{
	Elf32_Word	st_name;	/* Symbol name (string tbl index) */
	Elf32_Addr	st_value;	/* Symbol value */
	Elf32_Word	st_size;	/* Symbol size */
	unsigned char	st_info;	/* Symbol type and binding */
	unsigned char	st_other;	/* Symbol visibility */
	Elf32_Section	st_shndx;	/* Section index */
} Elf32_Sym;

typedef struct
{
	Elf64_Word	st_name;	/* Symbol name (string tbl index) */
	unsigned char	st_info;	/* Symbol type and binding */
	unsigned char st_other;		/* Symbol visibility */
	Elf64_Section	st_shndx;	/* Section index */
	Elf64_Addr	st_value;	/* Symbol value */
	Elf64_Xword	st_size;	/* Symbol size */
} Elf64_Sym;

/* Relocation table entry without addend (in section of type SHT_REL).  */

typedef struct
{
	Elf32_Addr	r_offset;	/* Address */
	Elf32_Word	r_info;		/* Relocation type and symbol index */
} Elf32_Rel;

/* I have seen two different definitions of the Elf64_Rel and
 Elf64_Rela structures, so we'll leave them out until Novell (or
 whoever) gets their act together.  */
/* The following, at least, is used on Sparc v9, MIPS, and Alpha.  */

typedef struct
{
	Elf64_Addr	r_offset;	/* Address */
	Elf64_Xword	r_info;		/* Relocation type and symbol index */
} Elf64_Rel;

/* Relocation table entry with addend (in section of type SHT_RELA).  */

typedef struct
{
	Elf32_Addr	r_offset;	/* Address */
	Elf32_Word	r_info;		/* Relocation type and symbol index */
	Elf32_Sword	r_addend;	/* Addend */
} Elf32_Rela;

typedef struct
{
	Elf64_Addr	r_offset;	/* Address */
	Elf64_Xword	r_info;		/* Relocation type and symbol index */
	Elf64_Sxword	r_addend;	/* Addend */
} Elf64_Rela;

/* How to extract and insert information held in the r_info field.  */

#define ELF32_R_SYM(val)		((val) >> 8)
#define ELF32_R_TYPE(val)		((val) & 0xff)
#define ELF32_R_INFO(sym, type)		(((sym) << 8) +((type) & 0xff))

#define ELF64_R_SYM(i)			((i) >> 32)
#define ELF64_R_TYPE(i)			((i) & 0xffffffff)
#define ELF64_R_INFO(sym,type)		((((Elf64_Xword) (sym)) << 32) +(type))


/* Intel 80386 specific definitions.  */

/* i386 relocs.  */

#define R_386_NONE	   0		/* No reloc */
#define R_386_32	   1		/* Direct 32 bit  */
#define R_386_PC32	   2		/* PC relative 32 bit */
#define R_386_GOT32	   3		/* 32 bit GOT entry */
#define R_386_PLT32	   4		/* 32 bit PLT address */
#define R_386_COPY	   5		/* Copy symbol at runtime */
#define R_386_GLOB_DAT	   6		/* Create GOT entry */
#define R_386_JMP_SLOT	   7		/* Create PLT entry */
#define R_386_RELATIVE	   8		/* Adjust by program base */
#define R_386_GOTOFF	   9		/* 32 bit offset to GOT */
#define R_386_GOTPC	   10		/* 32 bit PC relative offset to GOT */
#define R_386_32PLT	   11
#define R_386_TLS_TPOFF	   14		/* Offset in static TLS block */
#define R_386_TLS_IE	   15		/* Address of GOT entry for static TLS
					   block offset */
#define R_386_TLS_GOTIE	   16		/* GOT entry for static TLS block
					   offset */
#define R_386_TLS_LE	   17		/* Offset relative to static TLS
					   block */
#define R_386_TLS_GD	   18		/* Direct 32 bit for GNU version of
					   general dynamic thread local data */
#define R_386_TLS_LDM	   19		/* Direct 32 bit for GNU version of
					   local dynamic thread local data
					   in LE code */
#define R_386_16	   20
#define R_386_PC16	   21
#define R_386_8		   22
#define R_386_PC8	   23
#define R_386_TLS_GD_32	   24		/* Direct 32 bit for general dynamic
					   thread local data */
#define R_386_TLS_GD_PUSH  25		/* Tag for pushl in GD TLS code */
#define R_386_TLS_GD_CALL  26		/* Relocation for call to
					   __tls_get_addr() */
#define R_386_TLS_GD_POP   27		/* Tag for popl in GD TLS code */
#define R_386_TLS_LDM_32   28		/* Direct 32 bit for local dynamic
					   thread local data in LE code */
#define R_386_TLS_LDM_PUSH 29		/* Tag for pushl in LDM TLS code */
#define R_386_TLS_LDM_CALL 30		/* Relocation for call to
					   __tls_get_addr() in LDM code */
#define R_386_TLS_LDM_POP  31		/* Tag for popl in LDM TLS code */
#define R_386_TLS_LDO_32   32		/* Offset relative to TLS block */
#define R_386_TLS_IE_32	   33		/* GOT entry for negated static TLS
					   block offset */
#define R_386_TLS_LE_32	   34		/* Negated offset relative to static
					   TLS block */
#define R_386_TLS_DTPMOD32 35		/* ID of module containing symbol */
#define R_386_TLS_DTPOFF32 36		/* Offset in TLS block */
#define R_386_TLS_TPOFF32  37		/* Negated offset in static TLS block *//* Keep this the last entry.  */
#define R_386_NUM	   38

#endif /* ASSEMBLY */

#endif /* ELF_H */