github.com/goproxy0/go@v0.0.0-20171111080102-49cc0c489d2c/src/runtime/vdso_linux_386.go (about)

     1  // Copyright 2012 The Go Authors. All rights reserved.
     2  // Use of this source code is governed by a BSD-style
     3  // license that can be found in the LICENSE file.
     4  
     5  package runtime
     6  
     7  // ELF32 structure definitions for use by the Linux vDSO loader
     8  
     9  type elfSym struct {
    10  	st_name  uint32
    11  	st_value uint32
    12  	st_size  uint32
    13  	st_info  byte
    14  	st_other byte
    15  	st_shndx uint16
    16  }
    17  
    18  type elfVerdef struct {
    19  	vd_version uint16 /* Version revision */
    20  	vd_flags   uint16 /* Version information */
    21  	vd_ndx     uint16 /* Version Index */
    22  	vd_cnt     uint16 /* Number of associated aux entries */
    23  	vd_hash    uint32 /* Version name hash value */
    24  	vd_aux     uint32 /* Offset in bytes to verdaux array */
    25  	vd_next    uint32 /* Offset in bytes to next verdef entry */
    26  }
    27  
    28  type elfEhdr struct {
    29  	e_ident     [_EI_NIDENT]byte /* Magic number and other info */
    30  	e_type      uint16           /* Object file type */
    31  	e_machine   uint16           /* Architecture */
    32  	e_version   uint32           /* Object file version */
    33  	e_entry     uint32           /* Entry point virtual address */
    34  	e_phoff     uint32           /* Program header table file offset */
    35  	e_shoff     uint32           /* Section header table file offset */
    36  	e_flags     uint32           /* Processor-specific flags */
    37  	e_ehsize    uint16           /* ELF header size in bytes */
    38  	e_phentsize uint16           /* Program header table entry size */
    39  	e_phnum     uint16           /* Program header table entry count */
    40  	e_shentsize uint16           /* Section header table entry size */
    41  	e_shnum     uint16           /* Section header table entry count */
    42  	e_shstrndx  uint16           /* Section header string table index */
    43  }
    44  
    45  type elfPhdr struct {
    46  	p_type   uint32 /* Segment type */
    47  	p_offset uint32 /* Segment file offset */
    48  	p_vaddr  uint32 /* Segment virtual address */
    49  	p_paddr  uint32 /* Segment physical address */
    50  	p_filesz uint32 /* Segment size in file */
    51  	p_memsz  uint32 /* Segment size in memory */
    52  	p_flags  uint32 /* Segment flags */
    53  	p_align  uint32 /* Segment alignment */
    54  }
    55  
    56  type elfShdr struct {
    57  	sh_name      uint32 /* Section name (string tbl index) */
    58  	sh_type      uint32 /* Section type */
    59  	sh_flags     uint32 /* Section flags */
    60  	sh_addr      uint32 /* Section virtual addr at execution */
    61  	sh_offset    uint32 /* Section file offset */
    62  	sh_size      uint32 /* Section size in bytes */
    63  	sh_link      uint32 /* Link to another section */
    64  	sh_info      uint32 /* Additional section information */
    65  	sh_addralign uint32 /* Section alignment */
    66  	sh_entsize   uint32 /* Entry size if section holds table */
    67  }
    68  
    69  type elfDyn struct {
    70  	d_tag int32  /* Dynamic entry type */
    71  	d_val uint32 /* Integer value */
    72  }
    73  
    74  type elfVerdaux struct {
    75  	vda_name uint32 /* Version or dependency names */
    76  	vda_next uint32 /* Offset in bytes to next verdaux entry */
    77  }
    78  
    79  const (
    80  	// vdsoArrayMax is the byte-size of a maximally sized array on this architecture.
    81  	// See cmd/compile/internal/x86/galign.go arch.MAXWIDTH initialization, but must also
    82  	// be constrained to max +ve int.
    83  	vdsoArrayMax = 1<<31 - 1
    84  )
    85  
    86  var sym_keys = []symbol_key{
    87  	{"__vdso_clock_gettime", 0xd35ec75, 0x6e43a318, &__vdso_clock_gettime_sym},
    88  }
    89  
    90  // initialize to fall back to syscall
    91  var (
    92  	__vdso_clock_gettime_sym uintptr = 0
    93  )