CryptContextAddRef

This function is used to add one to the reference count on an HCRYPTPROV handle.

At a Glance

Header file:	Wincrypt.h
Windows CE versions:	2.10 and later

Syntax

BOOL WINAPI CryptContextAddRef( HCRYPTPROV hProv, DWORD *pdwReserved, DWORD dFlags );

Parameters

hProv

[in] HCRYPTPROV handle for which the reference count is being incremented.

pdwReserved

[in] Reserved for future use; set to NULL.

dwFlags

[in] Specifies a bitmask of flags. This parameter is reserved for future use; set to 0.

Return Values

TRUE indicates success. FALSE indicates failure. To get extended error information, call GetLastError. Common values for GetLastError are described in the following table.

Value	Description
ERROR_INVALID_PARAMETER	One of the parameters contains an invalid value. This is most often an illegal pointer.

Remarks

CryptContextAddRef is used to increase the reference count on a HCRYPTPROV handle so that multiple calls to CryptReleaseContext are required to actually release the handle.

Example

HCRYPTPROV hProv = 0;

// Acquire a context handle
if (!CryptAcquireContext(&hProv, NULL, NULL, PROV_RSA_SIG, 0)) {
 printf("Error %x during CryptAcquireContext!\n", GetLastError);
 return;
}

if (!CryptContextAddRef(&hProv, NULL, 0)) {
 printf("Error %x during CryptContextAddRef!\n", GetLastError);
 return;
}

...

// The first call to CryptReleaseContext will not release the provider handle
// since the reference count has been bumped up.
if (!CryptReleaseContext(hProv, 0)) {
 printf("Error %x during CryptReleaseContext!\n", GetLastError);
 return;
}

// Release the provider handle.
if (!CryptReleaseContext(hProv, 0)) {
 printf("Error %x during CryptReleaseContext!\n", GetLastError);
 return;
}