/// <summary>
/// Attention: All loggers from all processes that write to the same
/// (<c>productFamily</c> - <c>product</c> - <c>componentGroup</c> - <c>processName</c>)
/// MUST use the same value for <c>rotateLogFileWhenLargerBytes</c>!
/// </summary>
/// <param name="filenameBaseInfo">Info required to construct the base file name.
/// Use the non-default (aka paramaterized) ctor to create valid <c>FilenameBaseInfo</c> instances.</param>
/// <param name="logGroupId">A unique ID for all loggers across all processes that write to the same file (or a set of rotating files).
/// Used for inter-process synchronization.</param>
/// <param name="preferredLogFileDirectory">Target folder for the log file.
/// Specify <c>null</c> to use default.</param>
/// <param name="rotateLogFileWhenLargerBytes">Log files will be rotated (new index used) when the file uses the specified size.
/// Specify a nagative value to disable size-based file rotation.
/// All loggers that write to the same file must use the same value for this parameter.
/// Use <c>FileLogSink.RotateLogFileWhenLargerBytesDefault</c> as a default.</param>
/// <param name="formatOptions">Formatting options for the log file.
/// Specify <c>null</c> to use default.</param>
/// <param name="newLogSink">OUT parameter containing the newly created <c>FileLogSink</c>.</param>
/// <returns><c>True</c> is a new <c>FileLogSink</c> was created and initialized, <c>False</c> otherwise.</returns>
public static bool TryCreateNewFileLogSink(
FilenameBaseInfo filenameBaseInfo,
Guid logGroupId,
string preferredLogFileDirectory,
int rotateLogFileWhenLargerBytes,
DefaultFormat.Options formatOptions,
out FileLogSink newLogSink)
{
FilenameBaseInfo.EnsureValidAsParam(filenameBaseInfo);
// If user speficied a log file directory, we try to use it. If it fails we fry to fall back to defaults.
if (!String.IsNullOrWhiteSpace(preferredLogFileDirectory))
{
if (FileLogSink.TryCreateNew(preferredLogFileDirectory, filenameBaseInfo.LogFilenameBase, logGroupId, rotateLogFileWhenLargerBytes, formatOptions, out newLogSink))
{
return(true);
}
}
// If specified and accessible, use the Env Var for the log folder:
{
string userSetDdTraceLogDir = ReadEnvironmentVariable(DdTraceLogDirectoryEnvVarName);
if (FileLogSink.TryCreateNew(userSetDdTraceLogDir, filenameBaseInfo.LogFilenameBase, logGroupId, rotateLogFileWhenLargerBytes, formatOptions, out newLogSink))
{
return(true);
}
}
// If accessible, use the default for the log folder:
{
string defaultProductFamilyLogDir;
try
{
if (FileLogSink.IsWindowsFileSystem)
{
string commonAppDataDir = Environment.GetFolderPath(Environment.SpecialFolder.CommonApplicationData);
defaultProductFamilyLogDir =
Path.Combine(
commonAppDataDir,
WindowsDefaultLogDirectory,
filenameBaseInfo.ProductFamily ?? FilenameMissingComponentFallback);
}
else
{
defaultProductFamilyLogDir = Path.Combine(NixDefaultLogDirectory, (filenameBaseInfo.ProductFamily ?? FilenameMissingComponentFallback).ToLower());
}
}
catch
{
defaultProductFamilyLogDir = null;
}
if (FileLogSink.TryCreateNew(defaultProductFamilyLogDir, filenameBaseInfo.LogFilenameBase, logGroupId, rotateLogFileWhenLargerBytes, formatOptions, out newLogSink))
{
return(true);
}
}
// If we could not use the above folders, try using the application folder, is accessible:
{
string appDir;
try
{
appDir = Environment.CurrentDirectory;
}
catch
{
appDir = null;
}
if (FileLogSink.TryCreateNew(appDir, filenameBaseInfo.LogFilenameBase, logGroupId, rotateLogFileWhenLargerBytes, formatOptions, out newLogSink))
{
return(true);
}
}
// As last resort, we will try using the temp directory:
{
string tempDir;
try
{
tempDir = Path.GetTempPath();
}
catch
{
tempDir = null;
}
if (FileLogSink.TryCreateNew(tempDir, filenameBaseInfo.LogFilenameBase, logGroupId, rotateLogFileWhenLargerBytes, formatOptions, out newLogSink))
{
return(true);
}
}
// We could not write logs into any of the abofe folders. Give up.
newLogSink = null;
return(false);
}
