private static void GetFullPathName(ReadOnlySpan <char> path, ref ValueStringBuilder builder)
{
// If the string starts with an extended prefix we would need to remove it from the path before we call GetFullPathName as
// it doesn't root extended paths correctly. We don't currently resolve extended paths, so we'll just assert here.
Debug.Assert(PathInternal.IsPartiallyQualified(path) || !PathInternal.IsExtended(path));
uint result;
while ((result = Interop.Kernel32.GetFullPathNameW(ref MemoryMarshal.GetReference(path), (uint)builder.Capacity, ref builder.GetPinnableReference(), IntPtr.Zero)) > builder.Capacity)
{
// Reported size is greater than the buffer size. Increase the capacity.
builder.EnsureCapacity(checked ((int)result));
}
if (result == 0)
{
// Failure, get the error and throw
int errorCode = Marshal.GetLastWin32Error();
if (errorCode == 0)
{
errorCode = Interop.Errors.ERROR_BAD_PATHNAME;
}
throw Win32Marshal.GetExceptionForWin32Error(errorCode, path.ToString());
}
builder.Length = (int)result;
}
private unsafe string? GetServiceDisplayName(SafeServiceHandle? scmHandle, string serviceName)
{
var builder = new ValueStringBuilder(4096);
int bufLen;
while (true)
{
bufLen = builder.Capacity;
fixed (char* c = builder)
{
if (Interop.Advapi32.GetServiceDisplayName(scmHandle, serviceName, c, ref bufLen))
break;
}
int lastError = Marshal.GetLastWin32Error();
if (lastError == Interop.Errors.ERROR_SERVICE_DOES_NOT_EXIST)
{
return null;
}
else if (lastError != Interop.Errors.ERROR_INSUFFICIENT_BUFFER)
{
throw new InvalidOperationException(SR.Format(SR.NoService, serviceName, _machineName), new Win32Exception(lastError));
}
builder.EnsureCapacity(bufLen + 1); // Does not include null
}
builder.Length = bufLen;
return builder.ToString();
}
// This is only used by RegistryKey on Windows.
internal static string ExpandEnvironmentVariables(string name)
{
Debug.Assert(name != null);
if (name.Length == 0)
{
return(name);
}
Span <char> initialBuffer = stackalloc char[128];
var builder = new ValueStringBuilder(initialBuffer);
uint length;
while ((length = Win32Native.ExpandEnvironmentStringsW(name, ref builder.GetPinnableReference(), (uint)builder.Capacity)) > builder.Capacity)
{
builder.EnsureCapacity((int)length);
}
if (length == 0)
{
Marshal.ThrowExceptionForHR(Marshal.GetHRForLastWin32Error());
}
// length includes the null terminator
builder.Length = (int)length - 1;
return(builder.ToString());
}
// Returns a unique temporary file name, and creates a 0-byte file by that
// name on disk.
public static string GetTempFileName()
{
Span <char> initialTempPathBuffer = stackalloc char[PathInternal.MaxShortPath];
ValueStringBuilder tempPathBuilder = new ValueStringBuilder(initialTempPathBuffer);
GetTempPath(ref tempPathBuilder);
Span <char> initialBuffer = stackalloc char[PathInternal.MaxShortPath];
var builder = new ValueStringBuilder(initialBuffer);
uint result = 0;
while ((result = Interop.Kernel32.GetTempFileNameW(
ref tempPathBuilder.GetPinnableReference(), "tmp", 0, ref builder.GetPinnableReference())) > builder.Capacity)
{
// Reported size is greater than the buffer size. Increase the capacity.
builder.EnsureCapacity(checked ((int)result));
}
tempPathBuilder.Dispose();
if (result == 0)
{
throw Win32Marshal.GetExceptionForLastWin32Error();
}
builder.Length = (int)result;
string path = PathHelper.Normalize(ref builder);
builder.Dispose();
return(path);
}
internal static int PrependDevicePathChars(ref ValueStringBuilder content, bool isDosUnc, ref ValueStringBuilder buffer)
{
int length = content.Length;
length += isDosUnc
? PathInternal.UncExtendedPrefixLength - PathInternal.UncPrefixLength
: PathInternal.DevicePrefixLength;
buffer.EnsureCapacity(length + 1);
buffer.Length = 0;
if (isDosUnc)
{
// Is a \\Server\Share, put \\?\UNC\ in the front
buffer.Append(PathInternal.UncExtendedPathPrefix);
// Copy Server\Share\... over to the buffer
buffer.Append(content.AsSpan(PathInternal.UncPrefixLength));
// Return the prefix difference
return(PathInternal.UncExtendedPrefixLength - PathInternal.UncPrefixLength);
}
else
{
// Not an UNC, put the \\?\ prefix in front, then the original string
buffer.Append(PathInternal.ExtendedPathPrefix);
buffer.Append(content.AsSpan());
return(PathInternal.DevicePrefixLength);
}
}
public unsafe string GetRaw()
{
string variable = Variable;
if (variable == null)
{
throw new ArgumentNullException(nameof(variable));
}
Span <char> stack = stackalloc char[128];
ValueStringBuilder buffer = new ValueStringBuilder(stack);
uint returnValue;
while ((returnValue = Raw.GetEnvironmentVariable(variable, buffer.RawChars)) > buffer.Capacity)
{
buffer.EnsureCapacity((int)returnValue);
}
if (returnValue == 0)
{
return(null);
}
buffer.Length = (int)returnValue;
return(buffer.ToString());
}
public void EnsureCapacity_IfBufferTimesTwoWins()
{
Span <char> initialBuffer = stackalloc char[32];
var builder = new ValueStringBuilder(initialBuffer);
builder.EnsureCapacity(33);
Assert.Equal(64, builder.Capacity);
}
public static unsafe string Combine(params string[] paths)
{
if (paths == null)
{
throw new ArgumentNullException(nameof(paths));
}
int capacity = 0;
int num = 0;
for (int index = 0; index < paths.Length; ++index)
{
if (paths[index] == null)
{
throw new ArgumentNullException(nameof(paths));
}
if (paths[index].Length != 0)
{
if (Path.IsPathRooted(paths[index]))
{
num = index;
capacity = paths[index].Length;
}
else
{
capacity += paths[index].Length;
}
if (!PathInternal.IsDirectorySeparator(paths[index][paths[index].Length - 1]))
{
++capacity;
}
}
}
// ISSUE: untyped stack allocation
ValueStringBuilder valueStringBuilder = new ValueStringBuilder(new Span <char>((void *)__untypedstackalloc(new IntPtr(520)), 260));
valueStringBuilder.EnsureCapacity(capacity);
for (int index = num; index < paths.Length; ++index)
{
if (paths[index].Length != 0)
{
if (valueStringBuilder.Length == 0)
{
valueStringBuilder.Append(paths[index]);
}
else
{
if (!PathInternal.IsDirectorySeparator(valueStringBuilder[valueStringBuilder.Length - 1]))
{
valueStringBuilder.Append('\\');
}
valueStringBuilder.Append(paths[index]);
}
}
}
return(valueStringBuilder.ToString());
}
public void EnsureCapacityTest()
{
Span <char> buffer = stackalloc char[4];
using ValueStringBuilder sb = new ValueStringBuilder(buffer);
sb.EnsureCapacity(32);
Assert.True(sb.Capacity >= 32);
Assert.AreEqual(0, sb.Length);
}
public void EnsureCapacity_IfRequestedCapacityWins()
{
// Note: constants used here may be dependent on minimal buffer size
// the ArrayPool is able to return.
Span <char> initialBuffer = stackalloc char[32];
var builder = new ValueStringBuilder(initialBuffer);
builder.EnsureCapacity(65);
Assert.Equal(128, builder.Capacity);
}
public void EnsureCapacity_NoAllocIfNotNeeded()
{
// Note: constants used here may be dependent on minimal buffer size
// the ArrayPool is able to return.
Span <char> initialBuffer = stackalloc char[64];
var builder = new ValueStringBuilder(initialBuffer);
builder.EnsureCapacity(16);
Assert.Equal(64, builder.Capacity);
}
public static string Join(params string[] paths)
{
if (paths == null)
{
throw new ArgumentNullException(nameof(paths));
}
if (paths.Length == 0)
{
return(string.Empty);
}
int maxSize = 0;
foreach (string path in paths)
{
maxSize += path?.Length ?? 0;
}
maxSize += paths.Length - 1;
Span <char> initialBuffer = stackalloc char[260]; // MaxShortPath on Windows
var builder = new ValueStringBuilder(initialBuffer);
builder.EnsureCapacity(maxSize);
for (int i = 0; i < paths.Length; i++)
{
if ((paths[i]?.Length ?? 0) == 0)
{
continue;
}
string path = paths[i];
if (builder.Length == 0)
{
builder.Append(path);
}
else
{
if (!PathInternal.IsDirectorySeparator(builder[builder.Length - 1]) && !PathInternal.IsDirectorySeparator(path[0]))
{
builder.Append(PathInternal.DirectorySeparatorChar);
}
builder.Append(path);
}
}
return(builder.ToString());
}
private static void GetTempPath(ref ValueStringBuilder builder)
{
uint result;
while ((result = Interop.Kernel32.GetTempPathW(builder.Capacity, ref builder.GetPinnableReference())) > builder.Capacity)
{
// Reported size is greater than the buffer size. Increase the capacity.
builder.EnsureCapacity(checked ((int)result));
}
if (result == 0)
{
throw Win32Marshal.GetExceptionForLastWin32Error();
}
builder.Length = (int)result;
}
private static void GetUserName(ref ValueStringBuilder builder)
{
uint size = 0;
while (Interop.Secur32.GetUserNameExW(Interop.Secur32.NameSamCompatible, ref builder.GetPinnableReference(), ref size) == Interop.BOOLEAN.FALSE)
{
if (Marshal.GetLastWin32Error() == Interop.Errors.ERROR_MORE_DATA)
{
builder.EnsureCapacity(checked ((int)size));
}
else
{
builder.Length = 0;
return;
}
}
builder.Length = (int)size;
}
public static unsafe string Join([Nullable(new byte[] { 1, 2 })] params string[] paths)
{
if (paths == null)
{
throw new ArgumentNullException(nameof(paths));
}
if (paths.Length == 0)
{
return(string.Empty);
}
int num = 0;
foreach (string path in paths)
{
num += path != null ? path.Length : 0;
}
int capacity = num + (paths.Length - 1);
// ISSUE: untyped stack allocation
ValueStringBuilder valueStringBuilder = new ValueStringBuilder(new Span <char>((void *)__untypedstackalloc(new IntPtr(520)), 260));
valueStringBuilder.EnsureCapacity(capacity);
for (int index = 0; index < paths.Length; ++index)
{
string path = paths[index];
if (path != null && path.Length != 0)
{
if (valueStringBuilder.Length == 0)
{
valueStringBuilder.Append(path);
}
else
{
if (!PathInternal.IsDirectorySeparator(valueStringBuilder[valueStringBuilder.Length - 1]) && !PathInternal.IsDirectorySeparator(path[0]))
{
valueStringBuilder.Append('\\');
}
valueStringBuilder.Append(path);
}
}
}
return(valueStringBuilder.ToString());
}
public unsafe string GetRawInline()
{
string variable = Variable;
if (variable == null)
{
throw new ArgumentNullException(nameof(variable));
}
Span <char> stack = stackalloc char[128];
ValueStringBuilder buffer = new ValueStringBuilder(stack);
uint returnValue;
fixed(char *v = variable)
{
while (true)
{
fixed(char *b = buffer)
{
if ((returnValue = Raw.GetEnvironmentVariableW(v, b, (uint)buffer.Capacity))
<= buffer.Capacity)
{
break;
}
else
{
buffer.EnsureCapacity((int)returnValue);
}
}
}
;
}
if (returnValue == 0)
{
return(null);
}
buffer.Length = (int)returnValue;
return(buffer.ToString());
}
private static string ExpandEnvironmentVariablesCore(string name)
{
Span <char> initialBuffer = stackalloc char[128];
var builder = new ValueStringBuilder(initialBuffer);
uint length;
while ((length = Interop.Kernel32.ExpandEnvironmentStrings(name, ref builder.GetPinnableReference(), (uint)builder.Capacity)) > builder.Capacity)
{
builder.EnsureCapacity((int)length);
}
if (length == 0)
{
Marshal.ThrowExceptionForHR(Marshal.GetHRForLastWin32Error());
}
// length includes the null terminator
builder.Length = (int)length - 1;
return(builder.ToString());
}
public static string Combine(params string[] paths)
{
if (paths == null)
{
throw new ArgumentNullException(nameof(paths));
}
int maxSize = 0;
int firstComponent = 0;
// We have two passes, the first calculates how large a buffer to allocate and does some precondition
// checks on the paths passed in. The second actually does the combination.
for (int i = 0; i < paths.Length; i++)
{
if (paths[i] == null)
{
throw new ArgumentNullException(nameof(paths));
}
if (paths[i].Length == 0)
{
continue;
}
if (IsPathRooted(paths[i]))
{
firstComponent = i;
maxSize = paths[i].Length;
}
else
{
maxSize += paths[i].Length;
}
char ch = paths[i][paths[i].Length - 1];
if (!PathInternal.IsDirectorySeparator(ch))
{
maxSize++;
}
}
Span <char> initialBuffer = stackalloc char[260]; // MaxShortPath on Windows
var builder = new ValueStringBuilder(initialBuffer);
builder.EnsureCapacity(maxSize);
for (int i = firstComponent; i < paths.Length; i++)
{
if (paths[i].Length == 0)
{
continue;
}
if (builder.Length == 0)
{
builder.Append(paths[i]);
}
else
{
char ch = builder[builder.Length - 1];
if (!PathInternal.IsDirectorySeparator(ch))
{
builder.Append(PathInternal.DirectorySeparatorChar);
}
builder.Append(paths[i]);
}
}
return(builder.ToString());
}
internal static string TryExpandShortFileName(ref ValueStringBuilder outputBuilder, string?originalPath)
{
// We guarantee we'll expand short names for paths that only partially exist. As such, we need to find the part of the path that actually does exist. To
// avoid allocating a lot we'll create only one input array and modify the contents with embedded nulls.
Debug.Assert(!PathInternal.IsPartiallyQualified(outputBuilder.AsSpan()), "should have resolved by now");
// We'll have one of a few cases by now (the normalized path will have already:
//
// 1. Dos path (C:\)
// 2. Dos UNC (\\Server\Share)
// 3. Dos device path (\\.\C:\, \\?\C:\)
//
// We want to put the extended syntax on the front if it doesn't already have it (for long path support and speed), which may mean switching from \\.\.
//
// Note that we will never get \??\ here as GetFullPathName() does not recognize \??\ and will return it as C:\??\ (or whatever the current drive is).
int rootLength = PathInternal.GetRootLength(outputBuilder.AsSpan());
bool isDevice = PathInternal.IsDevice(outputBuilder.AsSpan());
// As this is a corner case we're not going to add a stackalloc here to keep the stack pressure down.
var inputBuilder = new ValueStringBuilder();
bool isDosUnc = false;
int rootDifference = 0;
bool wasDotDevice = false;
// Add the extended prefix before expanding to allow growth over MAX_PATH
if (isDevice)
{
// We have one of the following (\\?\ or \\.\)
inputBuilder.Append(outputBuilder.AsSpan());
if (outputBuilder[2] == '.')
{
wasDotDevice = true;
inputBuilder[2] = '?';
}
}
else
{
isDosUnc = !PathInternal.IsDevice(outputBuilder.AsSpan()) && outputBuilder.Length > 1 && outputBuilder[0] == '\\' && outputBuilder[1] == '\\';
rootDifference = PrependDevicePathChars(ref outputBuilder, isDosUnc, ref inputBuilder);
}
rootLength += rootDifference;
int inputLength = inputBuilder.Length;
bool success = false;
int foundIndex = inputBuilder.Length - 1;
while (!success)
{
uint result = Interop.Kernel32.GetLongPathNameW(
ref inputBuilder.GetPinnableReference(terminate: true), ref outputBuilder.GetPinnableReference(), (uint)outputBuilder.Capacity);
// Replace any temporary null we added
if (inputBuilder[foundIndex] == '\0')
{
inputBuilder[foundIndex] = '\\';
}
if (result == 0)
{
// Look to see if we couldn't find the file
int error = Marshal.GetLastWin32Error();
if (error != Interop.Errors.ERROR_FILE_NOT_FOUND && error != Interop.Errors.ERROR_PATH_NOT_FOUND)
{
// Some other failure, give up
break;
}
// We couldn't find the path at the given index, start looking further back in the string.
foundIndex--;
for (; foundIndex > rootLength && inputBuilder[foundIndex] != '\\'; foundIndex--)
{
;
}
if (foundIndex == rootLength)
{
// Can't trim the path back any further
break;
}
else
{
// Temporarily set a null in the string to get Windows to look further up the path
inputBuilder[foundIndex] = '\0';
}
}
else if (result > outputBuilder.Capacity)
{
// Not enough space. The result count for this API does not include the null terminator.
outputBuilder.EnsureCapacity(checked ((int)result));
}
else
{
// Found the path
success = true;
outputBuilder.Length = checked ((int)result);
if (foundIndex < inputLength - 1)
{
// It was a partial find, put the non-existent part of the path back
outputBuilder.Append(inputBuilder.AsSpan(foundIndex, inputBuilder.Length - foundIndex));
}
}
}
// If we were able to expand the path, use it, otherwise use the original full path result
ref ValueStringBuilder builderToUse = ref (success ? ref outputBuilder : ref inputBuilder);