lib/ntdll/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 PIMAGE_NT_HEADERS STDCALL
  21 RtlImageNtHeader (IN PVOID BaseAddress)
  22 {
  23         PIMAGE_NT_HEADERS NtHeader;
  24         PIMAGE_DOS_HEADER DosHeader = (PIMAGE_DOS_HEADER)BaseAddress;
  25
  26         if (DosHeader && DosHeader->e_magic != IMAGE_DOS_SIGNATURE)
  27         {
  28                 DPRINT1("DosHeader->e_magic %x\n", DosHeader->e_magic);
  29                 DPRINT1("NtHeader %x\n", (BaseAddress + DosHeader->e_lfanew));
  30         }
  31
  32 //      if (DosHeader && DosHeader->e_magic == IMAGE_DOS_SIGNATURE)
  33 //      {
  34                 NtHeader = (PIMAGE_NT_HEADERS)(BaseAddress + DosHeader->e_lfanew);
  35                 if (NtHeader->Signature == IMAGE_NT_SIGNATURE)
  36                         return NtHeader;
  37 //      }
  38         return NULL;
  39 }
  40
  41
  42 PVOID
  43 STDCALL
  44 RtlImageDirectoryEntryToData (
  45         PVOID   BaseAddress,
  46         BOOLEAN bFlag,
  47         ULONG   Directory,
  48         PULONG  Size
  49         )
  50 {
  51         PIMAGE_NT_HEADERS NtHeader;
  52         PIMAGE_SECTION_HEADER SectionHeader;
  53         ULONG Va;
  54         ULONG Count;
  55
  56         NtHeader = RtlImageNtHeader (BaseAddress);
  57         if (NtHeader == NULL)
  58                 return NULL;
  59
  60         if (Directory >= NtHeader->OptionalHeader.NumberOfRvaAndSizes)
  61                 return NULL;
  62
  63         Va = NtHeader->OptionalHeader.DataDirectory[Directory].VirtualAddress;
  64         if (Va == 0)
  65                 return NULL;
  66
  67         if (Size)
  68                 *Size = NtHeader->OptionalHeader.DataDirectory[Directory].Size;
  69
  70         if (bFlag)
  71                 return (PVOID)(BaseAddress + Va);
  72
  73         /* image mapped as ordinary file, we must find raw pointer */
  74         SectionHeader = (PIMAGE_SECTION_HEADER)(NtHeader + 1);
  75         Count = NtHeader->FileHeader.NumberOfSections;
  76         while (Count--)
  77         {
  78                 if (SectionHeader->VirtualAddress == Va)
  79                         return (PVOID)(BaseAddress + SectionHeader->PointerToRawData);
  80                 SectionHeader++;
  81         }
  82
  83         return NULL;
  84 }
  85
  86
  87 PIMAGE_SECTION_HEADER
  88 STDCALL
  89 RtlImageRvaToSection (
  90         PIMAGE_NT_HEADERS       NtHeader,
  91         PVOID                   BaseAddress,
  92         ULONG                   Rva
  93         )
  94 {
  95         PIMAGE_SECTION_HEADER Section;
  96         ULONG Va;
  97         ULONG Count;
  98
  99         Count = NtHeader->FileHeader.NumberOfSections;
 100         Section = (PIMAGE_SECTION_HEADER)((ULONG)&NtHeader->OptionalHeader +
 101                                           NtHeader->FileHeader.SizeOfOptionalHeader);
 102         while (Count)
 103         {
 104                 Va = Section->VirtualAddress;
 105                 if ((Va <= Rva) &&
 106                     (Rva < Va + Section->SizeOfRawData))
 107                         return Section;
 108                 Section++;
 109         }
 110         return NULL;
 111 }
 112
 113
 114 ULONG
 115 STDCALL
 116 RtlImageRvaToVa (
 117         PIMAGE_NT_HEADERS       NtHeader,
 118         PVOID                   BaseAddress,
 119         ULONG                   Rva,
 120         PIMAGE_SECTION_HEADER   *SectionHeader
 121         )
 122 {
 123         PIMAGE_SECTION_HEADER Section = NULL;
 124
 125         if (SectionHeader)
 126                 Section = *SectionHeader;
 127
 128         if (Section == NULL ||
 129             Rva < Section->VirtualAddress ||
 130             Rva >= Section->VirtualAddress + Section->SizeOfRawData)
 131         {
 132                 Section = RtlImageRvaToSection (NtHeader, BaseAddress, Rva);
 133                 if (Section == NULL)
 134                         return 0;
 135
 136                 if (SectionHeader)
 137                         *SectionHeader = Section;
 138         }
 139
 140         return (ULONG)(BaseAddress +
 141                        Rva +
 142                        Section->PointerToRawData -
 143                        Section->VirtualAddress);
 144 }
 145
 146 /* EOF */