Wrote a component test, which has a stand-in server thread

in place of an actual StorageManager.  The server thread
returns the same error over and over again.

Used that test to debug some basic comm stuff & find
errors in error handling.

utils/cloudio/CMakeLists.txt

@@ -4,7 +4,22 @@ set(cloudio_LIB_SRCS SMComm.cpp SMDataFile.cpp SMFileFactory.cpp SMFileSystem.cp
 
 add_library(cloudio SHARED ${cloudio_LIB_SRCS})
 
+# IDBDataFile currently depends on cloudio, which is backward.
+# Once cloudio has been turned into a proper plugin for idbdatafile,
+# we should be able to reverse the dependency like so:
+# target_link_libraries(cloudio idbdatafile messageqcpp loggingcpp)
+
 set_target_properties(cloudio PROPERTIES VERSION 1.0.0 SOVERSION 1)
 
 install(TARGETS cloudio DESTINATION ${ENGINE_LIBDIR} COMPONENT libs)
 
+add_executable(cloudio_component_test component_test.cpp)
+
+# see the comment above and change this dependency to cloudio.  Hm
+# our lib dependencies seem not to be declared.  Punting on that,
+# maybe in the future we can have some poor unfortunate intern
+# untangle all of that and declare lib dependencies properly.
+# For now I'm going to do like the other executables, which means
+# nearly everything AFAICT.
+target_link_libraries(cloudio_component_test ${ENGINE_LDFLAGS} ${ENGINE_EXEC_LIBS} ${MARIADB_CLIENT_LIBS})
+

utils/cloudio/SMFileFactory.cpp

@@ -90,7 +90,7 @@ IDBDataFile* SMFileFactory::open(const char *filename, const char *mode, unsigne
     SMComm *comm = SMComm::get();
     struct stat _stat;
     int err = comm->open(filename, posix_flags, &_stat);
-    if (!err)
+    if (err)
         return NULL;
         
     SMDataFile *ret = new SMDataFile(filename, posix_flags, _stat);

utils/cloudio/SocketPool.cpp

@@ -64,13 +64,6 @@ SocketPool::SocketPool()
         log(logging::LOG_TYPE_CRITICAL, os.str());
         maxSockets = defaultSockets;
     }
-    clientSocket = ::socket(AF_UNIX, SOCK_STREAM, 0);
-    if (clientSocket < 0) 
-    {
-        char buf[80], *ptr;
-        ptr = strerror_r(errno, buf, 80);
-        throw runtime_error("SocketPool(): Failed to get clientSocket, got " + string(ptr));
-    }
 }
 
 SocketPool::~SocketPool()
@@ -79,12 +72,12 @@ SocketPool::~SocketPool()
 
     for (uint i = 0; i < allSockets.size(); i++)
         ::close(allSockets[i]);
-    ::close(clientSocket);
 }
 
 #define sm_check_error \
     if (err < 0) \
     { \
+        cout << "SP: got an error on the socket" << endl; \
         returnSocket(sock); \
         return -1; \
     }
@@ -109,49 +102,63 @@ int SocketPool::send_recv(messageqcpp::ByteStream &in, messageqcpp::ByteStream *
         count += err;
         in.advance(err);
     }
+    //cout << "SP sent the msg" << endl;
     
     out->restart();
     uint8_t *outbuf;
     uint8_t window[8192];
-    bool foundHeader = false;
     length = 0;
     uint remainingBytes = 0;
     uint i;
     
-    /* TODO: consider adding timeouts on msg recv if we start using tcp sockets */
-    while (!foundHeader)
+    while (1)
     {
         // here remainingBytes means the # of bytes from the previous message
         err = ::read(sock, &window[remainingBytes], 8192 - remainingBytes);
         sm_check_error;
+        if (err == 0)
+        {
+            remoteClosed(sock);
+            // TODO, a retry loop
+            return -1;
+        }
         uint endOfData = remainingBytes + err;   // for clarity
         
         // scan for the 8-byte header.  If it is fragmented, move the fragment to the front of the buffer
         // for the next iteration to handle.
-        for (i = 0; i <= endOfData - 8 && !foundHeader; i++)
+        
+        if (endOfData < 8)
+        {
+            remainingBytes = endOfData;
+            continue;
+        }
+        
+        for (i = 0; i <= endOfData - 8; i++)
         {
             if (*((uint *) &window[i]) == storagemanager::SM_MSG_START)
             {
                 length = *((uint *) &window[i+4]);
-                foundHeader = true;
+                break;
             }
         }
         
-        if (!foundHeader)
+        if (length == 0)    // didn't find the header yet
         {
+            // i == endOfData - 7 here
             remainingBytes = endOfData - i;
-            if (i != 0)
             memmove(window, &window[i], remainingBytes);
-            else
-                continue;   // if i == 0, then the read was too short to see the whole header, do another read().
         }
         else
         {
+            // i == first byte of the header here
             // copy the payload fragment we got into the output bytestream
+            uint startOfPayload = i + 8;   // for clarity
             out->needAtLeast(length);
             outbuf = out->getInputPtr();
-            memcpy(outbuf, &window[i+8], endOfData - (i+8));
-            remainingBytes = length - (endOfData - (i+8));    // remainingBytes is now the # of bytes left to read
+            memcpy(outbuf, &window[startOfPayload], endOfData - startOfPayload);
+            remainingBytes = length - (endOfData - startOfPayload);    // remainingBytes is now the # of bytes left to read
+            out->advanceInputPtr(endOfData - startOfPayload);
+            break;   // done looking for the header, can fill the output buffer directly now.
         }
     }
     
@@ -170,7 +177,7 @@ int SocketPool::send_recv(messageqcpp::ByteStream &in, messageqcpp::ByteStream *
 int SocketPool::getSocket()
 {
     boost::mutex::scoped_lock lock(mutex);
-    int ret;
+    int clientSocket;
     
     if (freeSockets.size() == 0 && allSockets.size() < maxSockets)
     {
@@ -178,29 +185,31 @@ int SocketPool::getSocket()
         struct sockaddr_un addr;
         memset(&addr, 0, sizeof(addr));
         addr.sun_family = AF_UNIX;
-        strcpy(&addr.sun_path[0], storagemanager::socket_name);
-        ret = ::connect(clientSocket, (const struct sockaddr *) &addr, sizeof(addr));
-        if (ret >= 0)
-            allSockets.push_back(ret);
+        strcpy(&addr.sun_path[1], &storagemanager::socket_name[1]);   // first char is null...
+        clientSocket = ::socket(AF_UNIX, SOCK_STREAM, 0);
+        int err = ::connect(clientSocket, (const struct sockaddr *) &addr, sizeof(addr));
+        if (err >= 0)
+            allSockets.push_back(clientSocket);
         else
         {
             int saved_errno = errno;
             ostringstream os;
             char buf[80];
             os << "SocketPool::getSocket() failed to connect; got '" << strerror_r(saved_errno, buf, 80);
+            cout << os.str() << endl;
             log(logging::LOG_TYPE_CRITICAL, os.str());
             errno = saved_errno;
         }
-        return ret;
+        return clientSocket;
     }
     
     // wait for a socket to become free
     while (freeSockets.size() == 0)
         socketAvailable.wait(lock);
     
-    ret = freeSockets.front();
+    clientSocket = freeSockets.front();
     freeSockets.pop_front();
-    return ret;
+    return clientSocket;
 }
     
 void SocketPool::returnSocket(const int sock)
@@ -210,4 +219,17 @@ void SocketPool::returnSocket(const int sock)
     socketAvailable.notify_one();
 }
 
+void SocketPool::remoteClosed(const int sock)
+{
+    boost::mutex::scoped_lock lock(mutex);
+    ::close(sock);
+    for (vector<int>::iterator i = allSockets.begin(); i != allSockets.end(); ++i)
+        if (*i == sock)
+        {
+            allSockets.erase(i, i+1);
+            break;
+        }
+}
+
+
 }

utils/cloudio/SocketPool.h

@@ -42,14 +42,15 @@ class SocketPool : public boost::noncopyable
     private:
         int getSocket();
         void returnSocket(const int sock);
+        void remoteClosed(const int sock);
         
         std::vector<int> allSockets;
         std::deque<int> freeSockets;
         boost::mutex mutex;
         boost::condition_variable socketAvailable;
-        int clientSocket;
         uint maxSockets;
         static const uint defaultSockets = 20;
+        
 };
 
 }

utils/cloudio/component_test.cpp

@@ -0,0 +1,184 @@
+/* Copyright (C) 2014 InfiniDB, Inc.
+
+   This program is free software; you can redistribute it and/or
+   modify it under the terms of the GNU General Public License
+   as published by the Free Software Foundation; version 2 of
+   the License.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
+   MA 02110-1301, USA. */
+   
+   
+   
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <sys/un.h>
+#include <boost/thread.hpp>
+#include <unistd.h>
+#include <list>
+#include <string>
+
+#include "SMFileSystem.h"
+#include "SMDataFile.h"
+#include "SMFileFactory.h"
+#include "sm_exceptions.h"
+#include "messageFormat.h"
+
+/* The purpose of this is to test the idbdatafile cloud classes using a dummy
+SessionManager defined in this file. */
+
+#undef NDEBUG
+#include <assert.h>
+
+using namespace idbdatafile;
+using namespace std;
+
+volatile bool die = false;
+int errCode = 0;
+ 
+/* Right now this will just accept one connection & send a fixed error response */
+void error_server_thread()
+{
+    struct sockaddr_un addr;
+    memset(&addr, 0, sizeof(addr));
+    addr.sun_family = AF_UNIX;
+    strcpy(&addr.sun_path[1], &storagemanager::socket_name[1]);
+    
+    int server_socket = ::socket(AF_UNIX, SOCK_STREAM, 0);
+    assert(server_socket >= 0);
+    
+    int err = ::bind(server_socket, (struct sockaddr *) &addr, sizeof(addr));
+    assert(err == 0);
+    
+    err = ::listen(server_socket, 1);
+    assert(err == 0);
+    
+    socklen_t addrlen;
+    struct sockaddr_un client_addr;
+    memset(&client_addr, 0, sizeof(client_addr));
+    int client_socket = ::accept(server_socket, (struct sockaddr *) &client_addr, &addrlen);
+    assert(client_socket >= 0);
+    
+    //cout << "server thread got a connection" << endl;
+    
+    uint8_t buf[4096];
+    uint32_t response[4] = { storagemanager::SM_MSG_START, 8, (uint32_t ) -1, EINVAL };
+    uint remainingBytes = 0;
+    
+    while (!die) 
+    {
+        /* This just scans for SM_MSG_START, and as it finds them it sends a generic error
+           response. */
+        
+        err = ::recv(client_socket, &buf[remainingBytes], 4096 - remainingBytes, MSG_DONTWAIT);
+        if (err < 0)
+        {
+            if (errno == EAGAIN || errno == EWOULDBLOCK)
+            {
+                //cout << "server looping..." << endl;
+                sleep(1);   // who cares
+                continue;
+            }
+            else {
+                char errbuf[80];
+                //cout << "server thread got an error: " << strerror_r(errno, errbuf, 80) << endl;
+                close(client_socket);
+                errCode = -1;
+                die = true;
+                return;
+            }
+        }
+        
+        //cout << "server thread got some data" << endl;
+        uint endOfData = remainingBytes + err;
+        uint i;
+        if (endOfData < 4)
+        {
+            remainingBytes = endOfData;
+            continue;
+        }
+        for (i = 0; i <= endOfData - 4; i++)
+        {
+            if (*((uint32_t *) &buf[i]) == storagemanager::SM_MSG_START) {
+                //cout << "server thread found a msg start magic" << endl;
+                err = ::send(client_socket, response, 16, 0);
+                assert(err > 0);
+            }
+        }
+        memmove(buf, &buf[i], endOfData - i);   // should be the trailing 3 bytes of the data
+        remainingBytes = endOfData - i;
+    }
+} 
+ 
+int test1()
+{
+    /* Start a server thread that returns generic errors */
+    boost::thread server_thread(error_server_thread);
+    
+    /* Instantiate each of SM subclasses, call each function, and verify the expected error response */
+    int err;
+    SMFileFactory factory;
+    
+    cout << "open" << endl;
+    IDBDataFile *f = factory.open("dummy", "r", 0, 0);
+    assert(f == NULL && errno == EINVAL && !die);
+    
+    SMFileSystem filesystem;
+    
+    cout << "compressedSize" << endl;
+    bool gotException = false;
+    try {
+        filesystem.compressedSize("dummy");
+    }
+    catch (NotImplementedYet &) {
+        gotException = true;
+    }
+    assert(gotException && !die);
+    
+    cout << "copyFile" << endl;
+    try {
+        filesystem.copyFile("dummy1", "dummy2");
+    }
+    catch (NotImplementedYet &) {
+        gotException = true;
+    }
+    assert(gotException && !die);
+    
+    cout << "exists" << endl;
+    err = filesystem.exists("dummy");
+    assert(!err);
+    
+    cout << "filesystemisup" << endl;
+    err = filesystem.filesystemIsUp();
+    assert(!err && !die);
+    
+    cout << "isdir" << endl;
+    err = filesystem.isDir("dummy");
+    assert(!err && !die);
+    
+    cout << "listdirectory" << endl;
+    list<string> filenames;
+    err = filesystem.listDirectory("dummy", filenames);
+    assert(err == -1 && filenames.empty() && !die);
+    
+    // done, return errCode
+    die = true;
+    server_thread.join();
+    return errCode;
+}
+
+int main()
+{
+    int ret;
+    
+    ret = test1();
+    return ret;
+}
+    

utils/idbdatafile/IDBFactory.cpp

@@ -52,6 +52,9 @@ bool IDBFactory::installDefaultPlugins()
 
     s_plugins[IDBDataFile::BUFFERED] = FileFactoryEnt(IDBDataFile::BUFFERED, "buffered", new BufferedFileFactory(), new PosixFileSystem());
     s_plugins[IDBDataFile::UNBUFFERED] = FileFactoryEnt(IDBDataFile::UNBUFFERED, "unbuffered", new UnbufferedFileFactory(), new PosixFileSystem());
+    
+    // TODO: use the installPlugin fcn below instead of declaring this statically, then remove the dependency
+    // IDBDatafile -> cloudio
     s_plugins[IDBDataFile::CLOUD] = FileFactoryEnt(IDBDataFile::CLOUD, "cloud", new SMFileFactory(), new SMFileSystem());
     
     return false;