StringCbCopy (Windows CE 5.0)
Developing an Application > Safe String Functions > Safe String Reference > StrSafe.h Byte-Count Functions
This function is a replacement for strcpy.
The size, in bytes, of the destination buffer is provided to the function to ensure that StringCbCopy does not write past the end of this buffer.
HRESULT StringCbCopy( LPTSTR pszDest,
size_t cbDest,
LPCTSTR pszSrc);
Parameters
pszDest
[out] Pointer to a buffer that receives the copied string.cbDest
[in] Size of the destination buffer, in bytes.This value must consider the length of pszSrc, plus the terminating null character.
The maximum number of bytes allowed is STRSAFE_MAX_CCH * sizeof(TCHAR).
pszSrc
[in] Pointer to a buffer containing the source string.This source string must be null-terminated.
Return Value
This function returns an HRESULT, as opposed to strcpy, which returns a pointer.
It is strongly recommended that you use the SUCCEEDED and FAILED macros to test the return value of this function.
| Value | Description |
|---|---|
| S_OK | Source data was present, fully copied without truncation, and the resultant destination buffer is null-terminated. |
| STRSAFE_E_INVALID_PARAMETER | The value in cbDest is 0 or larger than the maximum allowed value. |
| STRSAFE_E_INSUFFICIENT_BUFFER | The copy operation failed due to insufficient buffer space.
The destination buffer contains a truncated, null-terminated version of the intended result. Where truncation is acceptable, this is not necessarily a failure condition. |
Remarks
StringCbCopy provides additional processing for proper buffer handling in your code.
Poor buffer handling is implicated in many security issues that involve buffer overruns. StringCbCopy always null-terminates a nonzero-length destination buffer.
StringCbCopy can be used in its generic form, or specifically as StringCbCopyA (for ANSI strings) or StringCbCopyW (for Unicode strings). The form to use is determined by your data.
| String data type | String literal | Function |
|---|---|---|
| char | "string" | StringCbCopyA |
| TCHAR | TEXT("string") | StringCbCopy |
| WCHAR | L"string" | StringCbCopyW |
StringCbCopy and its ANSI and Unicode variants are replacements for these functions:
This function is not a replacement for strncpy due to differences in behavior, and errors can result if you attempt to make that replacement. To replace strncpy, use StringCbCopyN or StringCbCopyNEx.
If the strings pointed to by pszSrc and pszDest overlap, behavior is undefined.
Neither pszSrc nor pszDest should be NULL.
If you need the handling of null string pointer values, see StringCbCopyEx.
Requirements
OS Versions: Windows CE 5.0 and later.
Header: strsafe.h.
Link Library: strsafe.lib.
See Also
StringCchCopy | StringCbCopyEx
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