windows-nt/Source/XPSP1/NT/enduser/stuff/delayimp/delayimp.c

//
// DelayImp.c
//
//  define structures and prototypes necessary for delay loading of imports
//

#include "windows.h"

typedef IMAGE_THUNK_DATA *          PImgThunkData;
typedef const IMAGE_THUNK_DATA *    PCImgThunkData;
typedef DWORD                       RVA;

typedef struct ImgDelayDescrV2 {
    DWORD           grAttrs;        // attributes
    RVA             rvaDLLName;     // RVA to dll name
    RVA             rvaHmod;        // RVA of module handle
    RVA             rvaIAT;         // RVA of the IAT
    RVA             rvaINT;         // RVA of the INT
    RVA             rvaBoundIAT;    // RVA of the optional bound IAT
    RVA             rvaUnloadIAT;   // RVA of optional copy of original IAT
    DWORD           dwTimeStamp;    // 0 if not bound,
                                    // O.W. date/time stamp of DLL bound to (Old BIND)
    } ImgDelayDescrV2, * PImgDelayDescrV2;

typedef ImgDelayDescrV2  ImgDelayDescr;
typedef PImgDelayDescrV2 PImgDelayDescr;

typedef const ImgDelayDescr *   PCImgDelayDescr;

enum DLAttr {                   // Delay Load Attributes
    dlattrRva = 0x1,                // RVAs are used instead of pointers
    };

//
// Delay load import hook notifications
//
enum {
    dliStartProcessing,             // used to bypass or note helper only
    dliNotePreLoadLibrary,          // called just before LoadLibrary, can
                                    //  override w/ new HMODULE return val
    dliNotePreGetProcAddress,       // called just before GetProcAddress, can
                                    //  override w/ new FARPROC return value
    dliFailLoadLib,                 // failed to load library, fix it by
                                    //  returning a valid HMODULE
    dliFailGetProc,                 // failed to get proc address, fix it by
                                    //  returning a valid FARPROC
    dliNoteEndProcessing,           // called after all processing is done, no
                                    //  no bypass possible at this point except
                                    //  by longjmp()/throw()/RaiseException.
    };

typedef struct DelayLoadProc {
    BOOL                fImportByName;
    union {
        LPCSTR          szProcName;
        DWORD           dwOrdinal;
        };
    } DelayLoadProc;

typedef struct DelayLoadInfo {
    DWORD               cb;         // size of structure
    PCImgDelayDescr     pidd;       // raw form of data (everything is there)
    FARPROC *           ppfn;       // points to address of function to load
    LPCSTR              szDll;      // name of dll
    DelayLoadProc       dlp;        // name or ordinal of procedure
    HMODULE             hmodCur;    // the hInstance of the library we have loaded
    FARPROC             pfnCur;     // the actual function that will be called
    DWORD               dwLastError;// error received (if an error notification)
    } DelayLoadInfo, * PDelayLoadInfo;

typedef FARPROC (WINAPI *PfnDliHook)(
    unsigned        dliNotify,
    PDelayLoadInfo  pdli
    );

IMAGE_DOS_HEADER __ImageBase;

//
// Unload support
//

BOOL
WINAPI
__FUnloadDelayLoadedDLL2 (
    LPCSTR szDll
    )

{
    return FALSE;
}

// structure definitions for the list of unload records
typedef struct UnloadInfo * PUnloadInfo;
typedef struct UnloadInfo {
    PUnloadInfo     puiNext;
    PCImgDelayDescr pidd;
    } UnloadInfo;

// the default delay load helper places the unloadinfo records in the list
// headed by the following pointer.

PUnloadInfo __puiHead;

//
// Hook pointers
//

// The "notify hook" gets called for every call to the
// delay load helper.  This allows a user to hook every call and
// skip the delay load helper entirely.
//
// dliNotify == {
//  dliStartProcessing |
//  dliPreLoadLibrary  |
//  dliPreGetProc |
//  dliNoteEndProcessing}
//  on this call.
//

PfnDliHook   __pfnDliNotifyHook;

PfnDliHook   __pfnDliNotifyHook2;

PfnDliHook   __pfnDliFailureHook;

PfnDliHook   __pfnDliFailureHook2;