reactos/lib/rtl/image.c

   1 /* $Id$
   2  *
   3  * COPYRIGHT:       See COPYING in the top level directory
   4  * PROJECT:         ReactOS kernel
   5  * FILE:            lib/ntdll/rtl/image.c
   6  * PURPOSE:         Image handling functions
   7  * PROGRAMMER:      Eric Kohl
   8  * UPDATE HISTORY:
   9  *                  17/03/2000 Created
  10  */
  11
  12 #include <ddk/ntddk.h>
  13 #include <ntdll/rtl.h>
  14
  15 #define NDEBUG
  16 #include <ntdll/ntdll.h>
  17
  18 /* FUNCTIONS ****************************************************************/
  19
  20 /*
  21  * @implemented
  22  */
  23 PIMAGE_NT_HEADERS STDCALL
  24 RtlImageNtHeader (IN PVOID BaseAddress)
  25 {
  26   PIMAGE_NT_HEADERS NtHeader;
  27   PIMAGE_DOS_HEADER DosHeader = (PIMAGE_DOS_HEADER)BaseAddress;
  28
  29   if (DosHeader && DosHeader->e_magic != IMAGE_DOS_SIGNATURE)
  30     {
  31       DPRINT1("DosHeader->e_magic %x\n", DosHeader->e_magic);
  32       DPRINT1("NtHeader %x\n", (BaseAddress + DosHeader->e_lfanew));
  33     }
  34
  35   if (DosHeader && DosHeader->e_magic == IMAGE_DOS_SIGNATURE)
  36     {
  37       NtHeader = (PIMAGE_NT_HEADERS)(BaseAddress + DosHeader->e_lfanew);
  38       if (NtHeader->Signature == IMAGE_NT_SIGNATURE)
  39         return NtHeader;
  40     }
  41
  42   return NULL;
  43 }
  44
  45
  46 /*
  47  * @implemented
  48  */
  49 PVOID
  50 STDCALL
  51 RtlImageDirectoryEntryToData (
  52         PVOID   BaseAddress,
  53         BOOLEAN bFlag,
  54         ULONG   Directory,
  55         PULONG  Size
  56         )
  57 {
  58         PIMAGE_NT_HEADERS NtHeader;
  59         ULONG Va;
  60
  61         NtHeader = RtlImageNtHeader (BaseAddress);
  62         if (NtHeader == NULL)
  63                 return NULL;
  64
  65         if (Directory >= NtHeader->OptionalHeader.NumberOfRvaAndSizes)
  66                 return NULL;
  67
  68         Va = NtHeader->OptionalHeader.DataDirectory[Directory].VirtualAddress;
  69         if (Va == 0)
  70                 return NULL;
  71
  72         if (Size)
  73                 *Size = NtHeader->OptionalHeader.DataDirectory[Directory].Size;
  74
  75         if (bFlag)
  76                 return (PVOID)(BaseAddress + Va);
  77
  78         /* image mapped as ordinary file, we must find raw pointer */
  79         return (PVOID)RtlImageRvaToVa (NtHeader, BaseAddress, Va, NULL);
  80 }
  81
  82
  83 /*
  84  * @implemented
  85  */
  86 PIMAGE_SECTION_HEADER
  87 STDCALL
  88 RtlImageRvaToSection (
  89         PIMAGE_NT_HEADERS       NtHeader,
  90         PVOID                   BaseAddress,
  91         ULONG                   Rva
  92         )
  93 {
  94         PIMAGE_SECTION_HEADER Section;
  95         ULONG Va;
  96         ULONG Count;
  97
  98         Count = NtHeader->FileHeader.NumberOfSections;
  99         Section = (PIMAGE_SECTION_HEADER)((ULONG)&NtHeader->OptionalHeader +
 100                                           NtHeader->FileHeader.SizeOfOptionalHeader);
 101         while (Count)
 102         {
 103                 Va = Section->VirtualAddress;
 104                 if ((Va <= Rva) &&
 105                     (Rva < Va + Section->SizeOfRawData))
 106                         return Section;
 107                 Section++;
 108         }
 109         return NULL;
 110 }
 111
 112
 113 /*
 114  * @implemented
 115  */
 116 ULONG
 117 STDCALL
 118 RtlImageRvaToVa (
 119         PIMAGE_NT_HEADERS       NtHeader,
 120         PVOID                   BaseAddress,
 121         ULONG                   Rva,
 122         PIMAGE_SECTION_HEADER   *SectionHeader
 123         )
 124 {
 125         PIMAGE_SECTION_HEADER Section = NULL;
 126
 127         if (SectionHeader)
 128                 Section = *SectionHeader;
 129
 130         if (Section == NULL ||
 131             Rva < Section->VirtualAddress ||
 132             Rva >= Section->VirtualAddress + Section->SizeOfRawData)
 133         {
 134                 Section = RtlImageRvaToSection (NtHeader, BaseAddress, Rva);
 135                 if (Section == NULL)
 136                         return 0;
 137
 138                 if (SectionHeader)
 139                         *SectionHeader = Section;
 140         }
 141
 142         return (ULONG)(BaseAddress +
 143                        Rva +
 144                        Section->PointerToRawData -
 145                        Section->VirtualAddress);
 146 }
 147
 148 /* EOF */