fixed log rotation issue

Foundation/include/Poco/FileChannel.h

@@ -1,7 +1,7 @@
 //
 // FileChannel.h
 //
-// $Id: //poco/svn/Foundation/include/Poco/FileChannel.h#2 $
+// $Id: //poco/1.3/Foundation/include/Poco/FileChannel.h#2 $
 //
 // Library: Foundation
 // Package: Logging
@@ -87,6 +87,8 @@ class Foundation_API FileChannel: public Channel
 	///   * daily:         the file is rotated daily
 	///   * weekly:        the file is rotated every seven days
 	///   * monthly:       the file is rotated every 30 days
+	///   * <n> minutes:   the file is rotated every <n> minutes, 
+	///                    where <n> is an integer greater than zero.
 	///   * <n> hours:     the file is rotated every <n> hours, where
 	///                    <n> is an integer greater than zero.
 	///   * <n> days:      the file is rotated every <n> days, where
@@ -103,6 +105,14 @@ class Foundation_API FileChannel: public Channel
 	///   * <n> M:         the file is rotated when its size exceeds
 	///                    <n> Megabytes.
 	///
+	/// NOTE: For periodic log file rotation (daily, weekly, monthly, etc.),
+	/// the date and time of log file creation or last rotation is
+	/// written into the first line of the log file. This is because
+	/// there is no reliable way to find out the real creation date of
+	/// a file on many platforms (e.g., most Unix platforms do not
+	/// provide the creation date, and Windows has its own issues
+	/// with its "File System Tunneling Capabilities").
+	///
 	/// Using the "archive" property it is possible to specify
 	/// how archived log files are named. The following values
 	/// for the "archive" property are supported:
@@ -151,15 +161,11 @@ class Foundation_API FileChannel: public Channel
 	///   * <n> weeks:     the maximum age is <n> weeks.
 	///   * <n> months:    the maximum age is <n> months, where a month has 30 days.
 	///
-	/// Both empty string ("") and n == 0 indicate no purging.
-	///
 	/// The purgeCount property has an integer value that
 	/// specifies the maximum number of archived log files.
 	/// If the number is exceeded, archived log files are 
 	/// deleted, starting with the oldest.
 	///
-	/// Both empty string ("") and "0" for indicate no purging.
-	///
 	/// For a more lightweight file channel class, see SimpleFileChannel.
 {
 public:

Foundation/include/Poco/RotateStrategy.h

@@ -1,7 +1,7 @@
 //
 // RotateStrategy.h
 //
-// $Id: //poco/svn/Foundation/include/Poco/RotateStrategy.h#2 $
+// $Id: //poco/1.3/Foundation/include/Poco/RotateStrategy.h#3 $
 //
 // Library: Foundation
 // Package: Logging
@@ -114,7 +114,7 @@ public:
 	{
 	}
 	
-	bool mustRotate(LogFile* pFile = 0)
+	bool mustRotate(LogFile* pFile)
 	{
 		if (DT() >= _threshold)
 		{
@@ -149,6 +149,11 @@ private:
 class Foundation_API RotateByIntervalStrategy: public RotateStrategy
 	/// The file is rotated when the log file 
 	/// exceeds a given age.
+	///
+	/// For this to work reliably across all platforms and file systems
+	/// (there are severe issues on most platforms finding out the real
+	/// creation date of a file), the creation date of the file is
+	/// written into the log file as the first entry.
 {
 public:
 	RotateByIntervalStrategy(const Timespan& span);
@@ -157,6 +162,8 @@ public:
 
 private:
 	Timespan _span;
+	Timestamp _lastRotate;
+	static const std::string ROTATE_TEXT;
 };
 
 

Foundation/include/Poco/Unicode.h

@@ -1,7 +1,7 @@
 //
 // Unicode.h
 //
-// $Id: //poco/1.3/Foundation/include/Poco/Unicode.h#1 $
+// $Id: //poco/1.3/Foundation/include/Poco/Unicode.h#2 $
 //
 // Library: Foundation
 // Package: Text

Foundation/src/FileChannel.cpp

@@ -1,7 +1,7 @@
 //
 // FileChannel.cpp
 //
-// $Id: //poco/svn/Foundation/src/FileChannel.cpp#2 $
+// $Id: //poco/1.3/Foundation/src/FileChannel.cpp#3 $
 //
 // Library: Foundation
 // Package: Logging
@@ -130,6 +130,10 @@ void FileChannel::log(const Message& msg)
 		{
 			_pFile = new LogFile(_path);
 		}
+		// we must call mustRotate() again to give the
+		// RotateByIntervalStrategy a chance to write its timestamp
+		// to the new file.
+		_pRotateStrategy->mustRotate(_pFile);
 	}
 	_pFile->write(msg.getText());
 }
@@ -240,6 +244,8 @@ void FileChannel::setRotation(const std::string& rotation)
 		pStrategy = new RotateByIntervalStrategy(Timespan(30*Timespan::DAYS));
 	else if (unit == "seconds") // for testing only
 		pStrategy = new RotateByIntervalStrategy(Timespan(n*Timespan::SECONDS));
+	else if (unit == "minutes")
+		pStrategy = new RotateByIntervalStrategy(Timespan(n*Timespan::MINUTES));
 	else if (unit == "hours")
 		pStrategy = new RotateByIntervalStrategy(Timespan(n*Timespan::HOURS));
 	else if (unit == "days")
@@ -296,14 +302,6 @@ void FileChannel::setCompress(const std::string& compress)
 
 void FileChannel::setPurgeAge(const std::string& age)
 {
-	if (age.empty())
-	{
-		delete _pPurgeStrategy;
-		_pPurgeStrategy = 0;
-		_purgeAge.clear();
-		return;
-	}
-
 	std::string::const_iterator it  = age.begin();
 	std::string::const_iterator end = age.end();
 	int n = 0;
@@ -328,12 +326,7 @@ void FileChannel::setPurgeAge(const std::string& age)
 		throw InvalidArgumentException("purgeAge", age);
 		
 	delete _pPurgeStrategy;
-	
-	if (0 == n || age.empty())
-		_pPurgeStrategy = 0;
-	else
-		_pPurgeStrategy = new PurgeByAgeStrategy(Timespan(factor*n));
-
+	_pPurgeStrategy = new PurgeByAgeStrategy(Timespan(factor*n));
 	_purgeAge = age;
 }
 
@@ -348,12 +341,7 @@ void FileChannel::setPurgeCount(const std::string& count)
 	while (it != end && std::isspace(*it)) ++it;
 
 	delete _pPurgeStrategy;
-
-	if (0 == n || count.empty())
-		_pPurgeStrategy = 0;
-	else
-		_pPurgeStrategy = new PurgeByCountStrategy(n);
-
+	_pPurgeStrategy = new PurgeByCountStrategy(n);
 	_purgeCount = count;
 }
 

Foundation/src/RotateStrategy.cpp

@@ -1,7 +1,7 @@
 //
 // RotateStrategy.cpp
 //
-// $Id: //poco/svn/Foundation/src/RotateStrategy.cpp#2 $
+// $Id: //poco/1.3/Foundation/src/RotateStrategy.cpp#2 $
 //
 // Library: Foundation
 // Package: Logging
@@ -35,6 +35,10 @@
 
 
 #include "Poco/RotateStrategy.h"
+#include "Poco/FileStream.h"
+#include "Poco/DateTimeParser.h"
+#include "Poco/DateTimeFormatter.h"
+#include "Poco/DateTimeFormat.h"
 
 
 namespace Poco {
@@ -60,7 +64,12 @@ RotateStrategy::~RotateStrategy()
 //
 
 
-RotateByIntervalStrategy::RotateByIntervalStrategy(const Timespan& span): _span(span)
+const std::string RotateByIntervalStrategy::ROTATE_TEXT("# Log file created/rotated ");
+
+
+RotateByIntervalStrategy::RotateByIntervalStrategy(const Timespan& span): 
+	_span(span),
+	_lastRotate(0)
 {
 	if (span.totalMicroseconds() <= 0) throw InvalidArgumentException("time span must be greater than zero");
 }
@@ -73,8 +82,31 @@ RotateByIntervalStrategy::~RotateByIntervalStrategy()
 
 bool RotateByIntervalStrategy::mustRotate(LogFile* pFile)
 {
+	if (_lastRotate == 0 || pFile->size() == 0)
+	{
+		if (pFile->size() != 0)
+		{
+			Poco::FileInputStream istr(pFile->path());
+			std::string tag;
+			std::getline(istr, tag);
+			if (tag.compare(0, ROTATE_TEXT.size(), ROTATE_TEXT) == 0)
+			{
+				std::string timestamp(tag, ROTATE_TEXT.size());
+				int tzd;
+				_lastRotate = DateTimeParser::parse(DateTimeFormat::RFC1036_FORMAT, timestamp, tzd).timestamp();
+			}
+			else _lastRotate = pFile->creationDate();
+		}
+		else
+		{
+			_lastRotate.update();
+			std::string tag(ROTATE_TEXT);
+			tag += DateTimeFormatter::format(_lastRotate, DateTimeFormat::RFC1036_FORMAT);
+			pFile->write(tag);
+		}
+	}
 	Timestamp now;
-	return _span <= now - pFile->creationDate();
+	return _span <= now - _lastRotate;
 }