Changed from checking pidfile to locking the config

git-svn-id: https://znc.svn.sourceforge.net/svnroot/znc/trunk@177 726aef4b-f618-498e-8847-2d620e286838

Utils.h

@@ -3,6 +3,8 @@
 
 #include <unistd.h>
 #include <ctype.h>
+#include <sys/time.h>
+#include <sys/file.h>
 
 #include <string>
 #include <vector>
@@ -19,8 +21,7 @@ using std::map;
 
 static const char g_HexDigits[] = "0123456789abcdef";
 
-class CUtils
-{
+class CUtils {
 public:
 	CUtils();
 	virtual ~CUtils();
@@ -56,14 +57,133 @@ public:
 	static string Token(const string& s, unsigned int uPos, bool bRest = false, char cSep = ' ');
 	static string Ellipsize(const string& s, unsigned int uLen);
 	static bool wildcmp(const string& sWild, const string& sString);
+
+	static unsigned long long GetMillTime() {
+		struct timeval tv;
+		unsigned long long iTime = 0;
+		gettimeofday(&tv, NULL);
+		iTime = (unsigned long long) tv.tv_sec * 1000;
+		iTime += ((unsigned long long) tv.tv_usec / 1000);
+		return iTime;
+	}
 #ifdef HAVE_LIBSSL
-	static void GenerateCert( FILE *pOut, bool bEncPrivKey = false );
+	static void GenerateCert(FILE *pOut, bool bEncPrivKey = false);
 #endif /* HAVE_LIBSSL */
-	
+
 private:
 protected:
 };
 
+class CLockFile {
+public:
+	CLockFile() {
+		m_bCreated = false;
+		m_fd = 0;
+		m_pid = 0;
+	}
+
+	CLockFile(const string& sFile) {
+		Open(sFile);
+	}
+
+	virtual ~CLockFile() {
+		if (getpid() == m_pid) {
+			if (m_fd > -1) {
+				UnLock();
+				close(m_fd);
+				if (m_bCreated) {
+					unlink(m_sFileName.c_str());
+				}
+			}
+		}
+	}
+
+	void Open(const string& sFile) {
+		m_fd = open(sFile.c_str(), O_RDONLY);
+		m_bCreated = false;
+
+		if (m_fd == -1) {
+			// i must create the file then
+			m_fd = open(sFile.c_str(), O_RDWR|O_CREAT, 0644);
+			m_bCreated = true;
+		}
+
+		m_pid = getpid();       // for destructor
+		m_sFileName = sFile;
+	}
+
+	//! timeout in milliseconds	
+	bool TryExLock(const string& sLockFile, unsigned long long iTimeout = 0) {
+		Open(sLockFile);
+		return TryExLock(iTimeout);
+	}
+
+	bool TryExLock(unsigned long long iTimeout = 0) {
+		if (iTimeout == 0) {
+			return Lock(LOCK_EX|LOCK_NB);
+		}
+
+		unsigned long long iNow = CUtils::GetMillTime();
+
+		while(true) {
+			if (Lock(LOCK_EX|LOCK_NB)) {
+				return true;
+			}
+
+			if ((CUtils::GetMillTime() - iNow) > iTimeout) {
+				break;
+			}
+
+			usleep(100);
+		}
+
+		return(false);
+	}
+
+	bool TryShLock(unsigned long long iTimeout = 0) {
+		if (iTimeout == 0) {
+			return(Lock(LOCK_SH|LOCK_NB));
+		}
+
+		unsigned long long iNow = CUtils::GetMillTime();
+
+		while(true) {
+			if (Lock(LOCK_SH|LOCK_NB)) {
+				return true;
+			}
+
+			if ((CUtils::GetMillTime() - iNow) > iTimeout) {
+				break;
+			}
+
+			usleep(100);
+		}
+
+		return false;
+	}
+
+	bool LockEx() { return Lock(LOCK_EX); }
+	bool LockSh() { return Lock(LOCK_SH); }
+	bool UnLock() { return Lock(LOCK_UN); }
+
+private:
+	bool Lock(int iOperation) {
+		if (m_fd == -1) {
+			return false;
+		}
+
+		if (::flock(m_fd, iOperation) != 0) {
+			return false;
+		}
+
+		return true;
+	}
+
+	int			m_fd;
+	int			m_pid;
+	bool		m_bCreated;
+	string		m_sFileName;
+};
 
 class CException {
 public:
@@ -106,8 +226,7 @@ public:
 	CFile(const string& sLongName);
 	virtual ~CFile();
 
-	enum EFileTypes
-	{
+	enum EFileTypes {
 		FT_REGULAR,
 		FT_DIRECTORY,
 		FT_CHARACTER,
@@ -117,26 +236,26 @@ public:
 		FT_SOCK
 	};
 
-	static bool IsReg( const string& sLongName, bool bUseLstat = false );
-	static bool IsDir( const string& sLongName, bool bUseLstat = false );
-	static bool IsChr( const string& sLongName, bool bUseLstat = false );
-	static bool IsBlk( const string& sLongName, bool bUseLstat = false );
-	static bool IsFifo( const string& sLongName, bool bUseLstat = false );
-	static bool IsLnk( const string& sLongName, bool bUseLstat = true );
-	static bool IsSock( const string& sLongName, bool bUseLstat = false );
+	static bool IsReg(const string& sLongName, bool bUseLstat = false);
+	static bool IsDir(const string& sLongName, bool bUseLstat = false);
+	static bool IsChr(const string& sLongName, bool bUseLstat = false);
+	static bool IsBlk(const string& sLongName, bool bUseLstat = false);
+	static bool IsFifo(const string& sLongName, bool bUseLstat = false);
+	static bool IsLnk(const string& sLongName, bool bUseLstat = true);
+	static bool IsSock(const string& sLongName, bool bUseLstat = false);
 
-	bool IsReg( bool bUseLstat = false );
-	bool IsDir( bool bUseLstat = false );
-	bool IsChr( bool bUseLstat = false );
-	bool IsBlk( bool bUseLstat = false );
-	bool IsFifo( bool bUseLstat = false );
-	bool IsLnk( bool bUseLstat = true );
-	bool IsSock( bool bUseLstat = false );
+	bool IsReg(bool bUseLstat = false);
+	bool IsDir(bool bUseLstat = false);
+	bool IsChr(bool bUseLstat = false);
+	bool IsBlk(bool bUseLstat = false);
+	bool IsFifo(bool bUseLstat = false);
+	bool IsLnk(bool bUseLstat = true);
+	bool IsSock(bool bUseLstat = false);
 
-	bool access( int mode );
+	bool access(int mode);
 
 	// for gettin file types, using fstat instead
-	static bool FType( const string sFileName, EFileTypes eType, bool bUseLstat = false );
+	static bool FType(const string sFileName, EFileTypes eType, bool bUseLstat = false);
 
 	enum EFileAttr {
 		FA_Name,
@@ -178,16 +297,16 @@ public:
 	bool Chmod(mode_t mode);
 	static bool Chmod(const string& sFile, mode_t mode);
 	bool Seek(unsigned long uPos);
-	bool Open( int iFlags, mode_t iMode = 0644 );
-	int Read( char *pszBuffer, int iBytes );
-	bool ReadLine( string & sData );
-	int Write( const char *pszBuffer, u_int iBytes );
-	int Write( const string & sData );
+	bool Open(int iFlags, mode_t iMode = 0644);
+	int Read(char *pszBuffer, int iBytes);
+	bool ReadLine(string & sData);
+	int Write(const char *pszBuffer, u_int iBytes);
+	int Write(const string & sData);
 	void Close();
 
 	string GetLongName() const;
 	string GetShortName() const;
-	void SetFD( int iFD );
+	void SetFD(int iFD);
 
 private:
 	string	m_sBuffer;
@@ -203,8 +322,7 @@ protected:
 #include <openssl/blowfish.h>
 #include <openssl/md5.h>
 //! does Blowfish w/64 bit feedback, no padding
-class CBlowfish
-{
+class CBlowfish {
 public:
 	/**
 	 * @sPassword key to encrypt with
@@ -217,7 +335,7 @@ public:
 	//! output must be freed
 	static unsigned char *MD5(const unsigned char *input, u_int ilen);
 
-	//! returns an md5 of the string ( not hex encoded )
+	//! returns an md5 of the string (not hex encoded)
 	static string MD5(const string & sInput, bool bHexEncode = false);
 
 	//! output must be the same size as input
@@ -241,9 +359,9 @@ inline bool ReadFile(const string & sFilename, string & sLine) {
 	int bytes;	
 	// clear ourselves out
 	sLine.clear();
-	
+
 	FILE *f = fopen(sFilename.c_str(), "r");
-	
+
 	if (!f) {
 		return false;
 	}
@@ -251,12 +369,12 @@ inline bool ReadFile(const string & sFilename, string & sLine) {
 	while((bytes = fread(inbuff, sizeof(char), RF_BUFF, f)) > 0) {
 		sLine.append(inbuff, bytes);
 	}
-	
+
 	fclose(f);
 	if (bytes < 0) {
 		return false;
 	}
-	
+
 	return true;
 }
 
@@ -269,7 +387,7 @@ inline bool WriteFile(const string & sFilename, const string & sData) {
 	int iRet = fwrite(sData.data(), sizeof(char), sData.length(), f);
 
 	fclose(f);
-	
+
 	if (iRet <= 0) {
 		return false;
 	}
@@ -312,7 +430,7 @@ inline string Upper(const string & sLine) {
 	for(u_int a = 0; a < sLine.length(); a++) {
 		sRet += toupper(sLine[a]);
 	}
-	
+
 	return sRet;
 }
 

znc.cpp

@@ -126,46 +126,6 @@ void CZNC::ReleaseISpoof() {
 	m_bISpoofLocked = false;
 }
 
-bool CZNC::SetPidFile(const string& sFile) {
-	CUtils::PrintAction("Checking PidFile [" + sFile + "]");
-
-	if (!sFile.empty() && sFile[0] != '/') {
-		m_sPidFile = GetZNCPath() + "/" + sFile;
-	} else {
-		m_sPidFile = sFile;
-	}
-
-	if (!m_sPidFile.empty()) {
-		unsigned int uPid = 0;
-		CFile File(m_sPidFile);
-
-		if (File.Open(O_RDONLY)) {
-			string sPid;
-
-			if (File.ReadLine(sPid)) {
-				uPid = atoi(sPid.c_str());
-
-				if (uPid > 0 && kill(uPid, 0) == 0) {
-					CUtils::PrintStatus(false, "ZNC already running [pid: " + CUtils::ToString(uPid) + "]");
-					File.Close();
-
-					return false;
-				} else {
-					CUtils::PrintStatus(true, "Stale pid, relaunching");
-					File.Close();
-
-					return true;
-				}
-			}
-
-			File.Close();
-		}
-	}
-
-	CUtils::PrintStatus(true);
-	return true;
-}
-
 bool CZNC::WritePidFile(int iPid) {
 	if (!m_sPidFile.empty()) {
 		CFile File(m_sPidFile);
@@ -270,6 +230,11 @@ bool CZNC::ParseConfig(const string& sConfigFile) {
 
 	CUtils::PrintAction("Opening Config [" + sFilePath + "]");
 
+	if (!m_LockFile.TryExLock(sFilePath, 50)) {
+		CUtils::PrintStatus(false, "ZNC is already running on this config.");
+		return false;
+	}
+
 	CFile File(sFilePath);
 
 	if (!File.Open(O_RDONLY)) {
@@ -526,10 +491,10 @@ bool CZNC::ParseConfig(const string& sConfigFile) {
 					m_sISpoofFile = sValue;
 					continue;
 				} else if (strcasecmp(sName.c_str(), "PidFile") == 0) {
-					if (!sValue.empty()) {
-						if (!SetPidFile(sValue)) {
-							return false;
-						}
+					if (!sValue.empty() && sValue[0] != '/') {
+						m_sPidFile = GetZNCPath() + "/" + sValue;
+					} else {
+						m_sPidFile = sValue;
 					}
 
 					continue;

znc.h

@@ -16,7 +16,6 @@ public:
 	void DeleteUsers();
 	int Loop();
 	void ReleaseISpoof();
-	bool SetPidFile(const string& sFile);
 	bool WritePidFile(int iPid);
 	CUser* GetUser(const string& sUser);
 	Csock* FindSockByName(const string& sSockName);
@@ -67,6 +66,7 @@ protected:
 	string					m_sISpoofFile;
 	string					m_sOrigISpoof;
 	string					m_sPidFile;
+	CLockFile				m_LockFile;
 	bool					m_bISpoofLocked;
 	bool					m_bSSL;
 	map<string,CUser*>::iterator	m_itUserIter;	// This needs to be reset to m_msUsers.begin() if anything is added or removed to the map