Changes: Error handling improvements.

Details: Throw std::runtime_error() instead of logErrorAndDie().

RevBy: Alexey Shilov

src/launcherlib/booster.cpp

@@ -34,6 +34,7 @@
 #include <fcntl.h>
 #include <cstring>
 #include <sstream>
+#include <stdexcept>
 
 #ifdef Q_WS_X11
 #include <X11/Xlib.h>
@@ -124,9 +125,8 @@ void Booster::initialize(int initialArgc, char ** initialArgv, int newBoosterLau
 
     // Wait and read commands from the invoker
     Logger::logDebug("Booster: Wait for message from invoker");
-    if (!receiveDataFromInvoker(socketFd)) {
-        Logger::logErrorAndDie(EXIT_FAILURE, "Booster: Couldn't read command\n");
-    }
+    if (!receiveDataFromInvoker(socketFd))
+        throw std::runtime_error("Booster: Couldn't read command\n");
 
     // Send parent process a message that it can create a new booster,
     // send pid of invoker, booster respawn value and invoker socket connection.
@@ -462,7 +462,11 @@ void Booster::setEnvironmentBeforeLaunch()
     if (err < 0)
     {
         // Credential setup has failed, abort.
-        Logger::logErrorAndDie(EXIT_FAILURE, "Booster: Failed to setup credentials for launching application: %d\n", err);
+        std::string msg("Booster: Failed to setup credentials for launching application: ");
+        std::stringstream ss;
+        ss << err;
+        msg += ss.str();
+        throw std::runtime_error(msg);
     }
 #endif
 
@@ -545,7 +549,8 @@ void* Booster::loadMain()
     void * module = dlopen(m_appData->fileName().c_str(), dlopenFlags);
 
     if (!module)
-        Logger::logErrorAndDie(EXIT_FAILURE, "Booster: Loading invoked application failed: '%s'\n", dlerror());
+        throw std::runtime_error(std::string("Booster: Loading invoked application failed: '") +
+                                 dlerror() + "'\n");
 
     // Find out the address for symbol "main". dlerror() is first used to clear any old error conditions,
     // then dlsym() is called, and then dlerror() is checked again. This procedure is documented
@@ -556,7 +561,8 @@ void* Booster::loadMain()
 
     const char * error_s = dlerror();
     if (error_s != NULL)
-        Logger::logErrorAndDie(EXIT_FAILURE, "Booster: Loading symbol 'main' failed: '%s'\n", error_s);
+        throw std::runtime_error(std::string("Booster: Loading symbol 'main' failed: '") +
+                                 error_s + "'\n");
 
     return module;
 }

src/launcherlib/connection.cpp

@@ -27,6 +27,7 @@
 #include <cstdlib>
 #include <cerrno>
 #include <unistd.h>
+#include <stdexcept>
 
 #if defined (HAVE_CREDS) && ! defined (DISABLE_VERIFICATION)
     const char * Connection::m_credsStr = "applauncherd-launcher::access";
@@ -57,9 +58,7 @@ Connection::Connection(int socketFd, bool testMode) :
     m_io[2] = -1;
 
     if (!m_testMode && m_curSocket == -1)
-    {
-        Logger::logErrorAndDie(EXIT_FAILURE, "Connection: Socket isn't initialized!\n");
-    }
+        throw std::runtime_error("Connection: Socket isn't initialized!\n");
 
 #if defined (HAVE_CREDS) && ! defined (DISABLE_VERIFICATION)
 

src/launcherlib/daemon.cpp

@@ -37,6 +37,7 @@
 #include <glob.h>
 #include <cstring>
 #include <cstdio>
+#include <stdexcept>
 
 #include "coverage.h"
 
@@ -57,7 +58,7 @@ Daemon::Daemon(int & argc, char * argv[]) :
     }
     else
     {
-        Logger::logErrorAndDie(EXIT_FAILURE, "Daemon: Daemon already created!\n");
+        throw std::runtime_error("Daemon: Daemon already created!\n");
     }
 
     // Parse arguments
@@ -73,12 +74,12 @@ Daemon::Daemon(int & argc, char * argv[]) :
 
     if (socketpair(AF_UNIX, SOCK_DGRAM, 0, m_boosterLauncherSocket) == -1)
     {
-        Logger::logErrorAndDie(EXIT_FAILURE, "Daemon: Creating a socket pair for boosters failed!\n");
+        throw std::runtime_error("Daemon: Creating a socket pair for boosters failed!\n");
     }
 
     if (pipe(m_sigPipeFd) == -1)
     {
-        Logger::logErrorAndDie(EXIT_FAILURE, "Daemon: Creating a pipe for Unix signals failed!\n");
+        throw std::runtime_error("Daemon: Creating a pipe for Unix signals failed!\n");
     }
 
     // Daemonize if desired
@@ -95,11 +96,11 @@ void Daemon::consoleQuiet()
     close(2);
 
     if (open("/dev/null", O_RDONLY) < 0)
-        Logger::logErrorAndDie(EXIT_FAILURE, "Daemon: Failed to open /dev/null as read-only");
+        throw std::runtime_error("Daemon: Failed to open /dev/null as read-only");
 
     int fd = open("/dev/null", O_WRONLY);
     if ((fd == -1) || (dup(fd) < 0))
-        Logger::logErrorAndDie(EXIT_FAILURE, "Daemon: Failed to open /dev/null as write-only");
+        throw std::runtime_error("Daemon: Failed to open /dev/null as write-only");
 }
 
 Daemon * Daemon::instance()
@@ -400,7 +401,7 @@ void Daemon::forkBooster(char type, int sleepTime)
     pid_t newPid = fork();
 
     if (newPid == -1)
-        Logger::logErrorAndDie(EXIT_FAILURE, "Daemon: Forking while invoking");
+        throw std::runtime_error("Daemon: Forking while invoking");
 
     if (newPid == 0) /* Child process */
     {
@@ -470,7 +471,7 @@ void Daemon::forkBooster(char type, int sleepTime)
         }
         else
         {
-            Logger::logErrorAndDie(EXIT_FAILURE, "Daemon: Unknown booster type '%c'\n", type);
+            throw std::runtime_error(std::string("Daemon: Unknown booster type '") + type + "'");
         }
     }
     else /* Parent process */
@@ -597,10 +598,7 @@ void Daemon::daemonize()
     // Fork off the parent process: first fork
     pid = fork();
     if (pid < 0)
-    {
-        Logger::logError("Daemon: Unable to fork daemon, code %d (%s)", errno, strerror(errno));
-        exit(EXIT_FAILURE);
-    }
+        throw std::runtime_error("Daemon: Unable to fork daemon");
 
     // If we got a good PID, then we can exit the parent process.
     if (pid > 0)
@@ -611,10 +609,7 @@ void Daemon::daemonize()
     // Fork off the parent process: second fork
     pid = fork();
     if (pid < 0)
-    {
-        Logger::logError("Daemon: Unable to fork daemon, code %d (%s)", errno, strerror(errno));
-        exit(EXIT_FAILURE);
-    }
+        throw std::runtime_error("Daemon: Unable to fork daemon");
 
     // If we got a good PID, then we can exit the parent process.
     if (pid > 0)
@@ -624,9 +619,7 @@ void Daemon::daemonize()
 
     // Check the lock
     if(!Daemon::lock())
-    {
-        Logger::logErrorAndDie(EXIT_FAILURE, "%s is already running \n", PROG_NAME_LAUNCHER);
-    }
+        throw std::runtime_error(std::string(PROG_NAME_LAUNCHER) + " is already running\n");
 
     // Change the file mode mask
     umask(0);
@@ -636,17 +629,11 @@ void Daemon::daemonize()
     // Create a new SID for the child process
     sid = setsid();
     if (sid < 0)
-    {
-        Logger::logError("Daemon: Unable to create a new session, code %d (%s)", errno, strerror(errno));
-        exit(EXIT_FAILURE);
-    }
+        throw std::runtime_error("Daemon: Unable to setsid.");
 
     // Change the current working directory
     if ((chdir("/")) < 0)
-    {
-        Logger::logError("Daemon: Unable to change directory to %s, code %d (%s)", "/", errno, strerror(errno));
-        exit(EXIT_FAILURE);
-    }
+        throw std::runtime_error("Daemon: Unable to chdir to '/'");
 
     // Open file descriptors pointing to /dev/null
     // Redirect standard file descriptors to /dev/null

src/launcherlib/logger.cpp

@@ -96,17 +96,6 @@ void Logger::logError(const char * format, ...)
     va_end(ap);
 }
 
-void Logger::logErrorAndDie(int code, const char * format, ...)
-{
-    va_list(ap);
-    va_start(ap, format);
-    writeLog(LOG_ERR, format, ap);
-    vfprintf(stderr, format, ap);
-    va_end(ap);
-
-    _exit(code);
-}
-
 void Logger::setDebugMode(bool enable)
 {
     Logger::m_debugMode = enable;

src/launcherlib/logger.h

@@ -79,15 +79,6 @@ public:
      */
     static void logInfo(const char * format, ...);
 
-    /*!
-     * \brief Log an error to the system message logger and exit
-     * \param format String identical to a printf format string
-     * \param additionalArgs Depending on the format string, the function may expect a
-     *        sequence of additional arguments, each containing one value to be inserted
-     *        in the format parameter, if any.
-     */
-    static void logErrorAndDie(int code, const char * format, ...);
-
     /*!
      * \brief Forces Logger to log everything and echo to stdout if set to true.
      */

src/launcherlib/main.cpp

@@ -28,6 +28,7 @@
 #include <signal.h>
 #include <fcntl.h>
 #include <sys/file.h>
+#include <stdexcept>
 
 #define DECL_EXPORT extern "C" __attribute__ ((__visibility__("default")))
 
@@ -79,28 +80,38 @@ DECL_EXPORT int main(int argc, char * argv[])
     {
         if(!Daemon::lock())
         {
-            Logger::logErrorAndDie(EXIT_FAILURE, "%s is already running \n", PROG_NAME_LAUNCHER);
+            Logger::logError("%s is already running \n", PROG_NAME_LAUNCHER);
+            return EXIT_FAILURE;
         }
     }
 
-    // Create main daemon instance
-    Daemon myDaemon(argc, argv);
+    try
+    {
+        // Create main daemon instance
+        Daemon myDaemon(argc, argv);
 
-    // Get fd for signal pipe.
-    g_sigPipeFd = myDaemon.sigPipeFd();
+        // Get fd for signal pipe.
+        g_sigPipeFd = myDaemon.sigPipeFd();
 
-    // Install signal handlers
-    signal(SIGCHLD, sigChldHandler); // reap zombies
-    signal(SIGTERM, sigTermHandler); // exit launcher
-    signal(SIGUSR1, sigUsr1Handler); // enter normal mode from boot mode
-    signal(SIGUSR2, sigUsr2Handler); // enter boot mode (same as --boot-mode)
-    signal(SIGPIPE, sigPipeHandler); // broken invoker's pipe 
+        // Install signal handlers
+        signal(SIGCHLD, sigChldHandler); // reap zombies
+        signal(SIGTERM, sigTermHandler); // exit launcher
+        signal(SIGUSR1, sigUsr1Handler); // enter normal mode from boot mode
+        signal(SIGUSR2, sigUsr2Handler); // enter boot mode (same as --boot-mode)
+        signal(SIGPIPE, sigPipeHandler); // broken invoker's pipe
 
-    // Run the main loop
-    myDaemon.run();
+        // Run the main loop
+        myDaemon.run();
 
-    // Close the log
-    Logger::closeLog();
+        // Close the log
+        Logger::closeLog();
+    }
+    catch (std::runtime_error & e)
+    {
+        Logger::logError(e.what());
+        std::cout << e.what() << std::endl;
+        return EXIT_FAILURE;
+    }
 
     return EXIT_SUCCESS;
 }

src/launcherlib/socketmanager.cpp

@@ -22,9 +22,13 @@
 
 #include <sys/socket.h>
 #include <sys/stat.h>
+#include <sys/types.h>
 #include <unistd.h>
 #include <cstdlib>
 #include <cstring>
+#include <stdexcept>
+#include <errno.h>
+#include <sstream>
 
 void SocketManager::initSocket(const string & socketId)
 {
@@ -37,14 +41,23 @@ void SocketManager::initSocket(const string & socketId)
         // Create a new local socket
         int socketFd = socket(PF_UNIX, SOCK_STREAM, 0);
         if (socketFd < 0)
-            Logger::logErrorAndDie(EXIT_FAILURE, "SocketManager: Failed to open socket\n");
+            throw std::runtime_error("SocketManager: Failed to open socket\n");
 
         // TODO: Error if socketId >= maxLen. Also unlink() here may
         // try to remove a different file than is passed to sun.sa_data.
 
         // Remove the previous socket file
-        if (unlink(socketId.c_str()))
-            Logger::logError("SocketManager: Failed to unlink existing socket file '%s'", socketId.c_str());
+        struct stat sb;
+        stat(socketId.c_str(), &sb);
+        if (S_ISSOCK(sb.st_mode))
+        {
+            if (unlink(socketId.c_str()) == -1)
+            {
+                std::string msg("SocketManager: Failed to unlink existing socket file '");
+                msg += socketId + "': " + strerror(errno);
+                Logger::logWarning(msg.c_str());
+            }
+        }
 
         // Initialize the socket struct
         struct sockaddr sun;
@@ -55,11 +68,23 @@ void SocketManager::initSocket(const string & socketId)
 
         // Bind the socket
         if (bind(socketFd, &sun, sizeof(sun)) < 0)
-            Logger::logErrorAndDie(EXIT_FAILURE, "SocketManager: Failed to bind to socket (fd=%d)\n", socketFd);
+        {
+            std::string msg("SocketManager: Failed to bind to socket (fd=");
+            std::stringstream ss;
+            ss << socketFd;
+            msg += ss.str() + ")";
+            throw std::runtime_error(msg);
+        }
 
         // Listen to the socket
         if (listen(socketFd, 10) < 0)
-            Logger::logErrorAndDie(EXIT_FAILURE, "SocketManager: Failed to listen to socket (fd=%d)\n", socketFd);
+        {
+            std::string msg("SocketManager: Failed to listen to socket (fd=");
+            std::stringstream ss;
+            ss << socketFd;
+            msg += ss.str() + ")";
+            throw std::runtime_error(msg);
+        }
 
         // Set permissions
         chmod(socketId.c_str(), S_IRUSR | S_IWUSR | S_IXUSR |