RtlGetLengthWithoutLastFullDosOrNtPathElement.c File Reference

#include "precomp.h"

Include dependency graph for RtlGetLengthWithoutLastFullDosOrNtPathElement.c:

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Classes
struct	_rtl_test_data

Typedefs
typedef struct _rtl_test_data	rtl_test_data

Functions
NTSTATUS NTAPI	RtlGetLengthWithoutLastFullDosOrNtPathElement (IN ULONG Flags, IN PCUNICODE_STRING Path, OUT PULONG LengthOut)
	START_TEST (RtlGetLengthWithoutLastFullDosOrNtPathElement)

Variables
rtl_test_data	tests []

Typedef Documentation

rtl_test_data

typedef struct _rtl_test_data rtl_test_data

Function Documentation

RtlGetLengthWithoutLastFullDosOrNtPathElement()

NTSTATUS NTAPI RtlGetLengthWithoutLastFullDosOrNtPathElement	(	IN ULONG	Flags,
		IN PCUNICODE_STRING	Path,
		OUT PULONG	LengthOut
	)

Definition at line 496 of file path.c.

{
    static const UNICODE_STRING PathDividers = RTL_CONSTANT_STRING(L"\\/");
    USHORT Position;
    RTL_PATH_TYPE PathType;
 
    /* All failure paths have this in common, so simplify code */
    if (LengthOut)
        *LengthOut = 0;
 
    if (Flags || !Path || !LengthOut)
    {
        return STATUS_INVALID_PARAMETER;
    }
 
    if ((Path->Length / sizeof(WCHAR)) == 0)
    {
        /* Nothing to do here */
        return STATUS_SUCCESS;
    }
 
 
    PathType = RtlDetermineDosPathNameType_Ustr(Path);
    switch (PathType)
    {
    case RtlPathTypeLocalDevice:
        // Handle \\\\?\\C:\\ with the last ':' or '\\' missing:
        if (Path->Length / sizeof(WCHAR) < 7 ||
            Path->Buffer[5] != ':' ||
            !IS_PATH_SEPARATOR(Path->Buffer[6]))
        {
            return STATUS_INVALID_PARAMETER;
        }
        break;
    case RtlPathTypeRooted:
        // "\\??\\"
        break;
    case RtlPathTypeUncAbsolute:
        // "\\\\"
        break;
    case RtlPathTypeDriveAbsolute:
        // "C:\\"
        break;
    default:
        return STATUS_INVALID_PARAMETER;
    }
 
    /* Find the last path separator */
    if (!NT_SUCCESS(RtlFindCharInUnicodeString(RTL_FIND_CHAR_IN_UNICODE_STRING_START_AT_END, Path, &PathDividers, &Position)))
        Position = 0;
 
    /* Is it the last char of the string? */
    if (Position && Position + sizeof(WCHAR) == Path->Length)
    {
        UNICODE_STRING Tmp = *Path;
        Tmp.Length = Position;
 
        /* Keep walking path separators to eliminate multiple next to eachother */
        while (Tmp.Length > sizeof(WCHAR) && IS_PATH_SEPARATOR(Tmp.Buffer[Tmp.Length / sizeof(WCHAR)]))
            Tmp.Length -= sizeof(WCHAR);
 
        /* Find the previous occurence */
        if (!NT_SUCCESS(RtlFindCharInUnicodeString(RTL_FIND_CHAR_IN_UNICODE_STRING_START_AT_END, &Tmp, &PathDividers, &Position)))
            Position = 0;
    }
 
    /* Simplify code by working in chars instead of bytes */
    if (Position)
        Position /= sizeof(WCHAR);
 
    if (Position)
    {
        // Keep walking path separators to eliminate multiple next to eachother, but ensure we leave one in place!
        while (Position > 1 && IS_PATH_SEPARATOR(Path->Buffer[Position - 1]))
            Position--;
    }
 
    if (Position > 0)
    {
        /* Return a length, not an index */
        *LengthOut = Position + 1;
    }
 
    return STATUS_SUCCESS;
}

Referenced by START_TEST().

START_TEST()

START_TEST

(

RtlGetLengthWithoutLastFullDosOrNtPathElement

)

Definition at line 75 of file RtlGetLengthWithoutLastFullDosOrNtPathElement.c.

{
    UNICODE_STRING Dum;
    NTSTATUS Status;
    ULONG Length;
    RtlInitUnicodeString(&Dum, L"c:\\test\\");
 
    Length = 333;
    Status = RtlGetLengthWithoutLastFullDosOrNtPathElement(0, NULL, &Length);
    ok_int(Length, 0);
    ok_hex(Status, STATUS_INVALID_PARAMETER);
 
    Status = RtlGetLengthWithoutLastFullDosOrNtPathElement(0, &Dum, NULL);
    ok_hex(Status, STATUS_INVALID_PARAMETER);
 
    for (ULONG n = 0; n < 32; ++n)
    {
        Length = 333;
        Status = RtlGetLengthWithoutLastFullDosOrNtPathElement((1 << n), &Dum, &Length);
        ok_int(Length, 0);
        ok_hex(Status, STATUS_INVALID_PARAMETER);
    }
 
    for (ULONG n = 0; n < ARRAYSIZE(tests); ++n)
    {
        UNICODE_STRING Str;
        Length = 333;
 
        RtlInitUnicodeString(&Str, tests[n].Path);
 
        Status = RtlGetLengthWithoutLastFullDosOrNtPathElement(0, &Str, &Length);
        ok(Status == tests[n].Status, "Got Status=0x%lx, expected 0x%lx (%S)\n", Status, tests[n].Status, Str.Buffer);
        ok(Length == tests[n].Length, "Got Length=0x%lx, expected 0x%lx (%S)\n", Length, tests[n].Length, Str.Buffer);
    }
}

Variable Documentation

tests

rtl_test_data tests[]

Definition at line 27 of file RtlGetLengthWithoutLastFullDosOrNtPathElement.c.

Referenced by START_TEST().