126 lines
2.8 KiB
C
126 lines
2.8 KiB
C
/*++
|
||
|
||
Copyright (c) 1992, 1993 Microsoft Corporation
|
||
|
||
Module Name:
|
||
|
||
packstr.c
|
||
|
||
Abstract:
|
||
|
||
Contains functions for packing strings into buffers that also contain
|
||
structures.
|
||
|
||
Author:
|
||
|
||
From LAN Manager netlib.
|
||
Rita Wong (ritaw) 2-Mar-1993
|
||
|
||
Environment:
|
||
|
||
User Mode - Win32
|
||
|
||
Revision History:
|
||
|
||
--*/
|
||
|
||
#include <procs.h>
|
||
|
||
|
||
BOOL
|
||
NwlibCopyStringToBuffer(
|
||
IN LPCWSTR SourceString OPTIONAL,
|
||
IN DWORD CharacterCount,
|
||
IN LPCWSTR FixedDataEnd,
|
||
IN OUT LPWSTR *EndOfVariableData,
|
||
OUT LPWSTR *VariableDataPointer
|
||
)
|
||
|
||
/*++
|
||
|
||
Routine Description:
|
||
|
||
This routine puts a single variable-length string into an output buffer.
|
||
The string is not written if it would overwrite the last fixed structure
|
||
in the buffer.
|
||
|
||
Arguments:
|
||
|
||
SourceString - Supplies a pointer to the source string to copy into the
|
||
output buffer. If SourceString is null then a pointer to a zero terminator
|
||
is inserted into output buffer.
|
||
|
||
CharacterCount - Supplies the length of SourceString, not including zero
|
||
terminator. (This in units of characters - not bytes).
|
||
|
||
FixedDataEnd - Supplies a pointer to just after the end of the last
|
||
fixed structure in the buffer.
|
||
|
||
EndOfVariableData - Supplies an address to a pointer to just after the
|
||
last position in the output buffer that variable data can occupy.
|
||
Returns a pointer to the string written in the output buffer.
|
||
|
||
VariableDataPointer - Supplies a pointer to the place in the fixed
|
||
portion of the output buffer where a pointer to the variable data
|
||
should be written.
|
||
|
||
Return Value:
|
||
|
||
Returns TRUE if string fits into output buffer, FALSE otherwise.
|
||
|
||
--*/
|
||
{
|
||
DWORD CharsNeeded = (CharacterCount + 1);
|
||
|
||
|
||
//
|
||
// Determine if source string will fit, allowing for a zero terminator.
|
||
// If not, just set the pointer to NULL.
|
||
//
|
||
|
||
if ((*EndOfVariableData - CharsNeeded) >= FixedDataEnd) {
|
||
|
||
//
|
||
// It fits. Move EndOfVariableData pointer up to the location where
|
||
// we will write the string.
|
||
//
|
||
|
||
*EndOfVariableData -= CharsNeeded;
|
||
|
||
//
|
||
// Copy the string to the buffer if it is not null.
|
||
//
|
||
|
||
if (CharacterCount > 0 && SourceString != NULL) {
|
||
|
||
(VOID) wcsncpy(*EndOfVariableData, SourceString, CharacterCount);
|
||
}
|
||
|
||
//
|
||
// Set the zero terminator.
|
||
//
|
||
|
||
*(*EndOfVariableData + CharacterCount) = L'\0';
|
||
|
||
//
|
||
// Set up the pointer in the fixed data portion to point to where the
|
||
// string is written.
|
||
//
|
||
|
||
*VariableDataPointer = *EndOfVariableData;
|
||
|
||
return TRUE;
|
||
|
||
}
|
||
else {
|
||
|
||
//
|
||
// It doesn't fit. Set the offset to NULL.
|
||
//
|
||
|
||
*VariableDataPointer = NULL;
|
||
|
||
return FALSE;
|
||
}
|
||
}
|