Cleaned up logger API, added truncation support to inMemoryLog.c

src/lladd/logger/inMemoryLog.c

@@ -24,12 +24,11 @@ int writeLogEntry_InMemoryLog(LogEntry *e) {
 
   int done = 0;
   do{ 
-    readlock(globalOffset_lock,0);
+    writelock(globalOffset_lock,0);
     bufferOffset = nextAvailableLSN - globalOffset;
     if(bufferOffset > bufferLen) { 
-      unlock(globalOffset_lock);
+      bufferLen *= 2;
-      writelock(globalOffset_lock,0);
+      buffer = realloc(buffer, bufferLen);
-      abort(); // really, need to extend log.
     } else {
       done = 1;
     }
@@ -38,8 +37,11 @@ int writeLogEntry_InMemoryLog(LogEntry *e) {
 
   e->LSN = nextAvailableLSN;
 
+  LogEntry * cpy = malloc(sizeofLogEntry(e));
+  memcpy(cpy, e, sizeofLogEntry(e));
+
   //  printf ("lsn: %ld\n", e->LSN);
-  buffer[bufferOffset] = e;
+  buffer[bufferOffset] = cpy;
 
   //  printf("lsn: %ld type: %d\n", e->LSN, e->type);
   nextAvailableLSN++;
@@ -53,8 +55,34 @@ lsn_t flushedLSN_InMemoryLog() {
   return nextAvailableLSN;
 }
 
+void syncLog_InMemoryLog() {
+  // no-op
+}
+
+lsn_t nextEntry_InMemoryLog(const LogEntry * e) { 
+  return e->LSN + 1;
+}
+
 int truncateLog_InMemoryLog(lsn_t lsn) {
-  abort();
+  writelock(flushedLSN_lock,1);
+  writelock(globalOffset_lock,1);
+ 
+  assert(lsn <= nextAvailableLSN);
+
+
+  if(lsn > globalOffset) { 
+    for(int i = globalOffset; i < lsn; i++) { 
+      free(buffer[i - globalOffset]);
+    }
+    assert((lsn-globalOffset) + (nextAvailableLSN -lsn) < bufferLen);
+    memmove(&(buffer[0]), &(buffer[lsn - globalOffset]), sizeof(LogEntry*) * (nextAvailableLSN - lsn));
+    globalOffset = lsn;
+  }
+
+  writeunlock(globalOffset_lock);
+  writeunlock(flushedLSN_lock);
+
+  return 0;
 }
 
 lsn_t firstLogEntry_InMemoryLog() {
@@ -78,15 +106,20 @@ void close_InMemoryLog() {
 
 }
 
-LogEntry * readLSNEntry_InMemoryLog(lsn_t LSN) { 
+LogEntry * readLSNEntry_InMemoryLog(lsn_t lsn) { 
-  // printf("lsn: %ld\n", LSN);
+  // printf("lsn: %ld\n", lsn);
-  if(LSN >= nextAvailableLSN) { return 0; } 
+  if(lsn >= nextAvailableLSN) { return 0; } 
-  assert(LSN-globalOffset >= 0 && LSN-globalOffset< bufferLen);
+  assert(lsn-globalOffset >= 0 && lsn-globalOffset< bufferLen);
   readlock(globalOffset_lock, 0);
-  LogEntry * ptr = buffer[LSN - globalOffset];
+  LogEntry * ptr = buffer[lsn - globalOffset];
   unlock(globalOffset_lock);
   assert(ptr);
-  assert(ptr->LSN == LSN);
+  assert(ptr->LSN == lsn);
+  
+  LogEntry * ret = malloc(sizeofLogEntry(ptr));
+
+  memcpy(ret, ptr, sizeofLogEntry(ptr));
+  
   //printf("lsn: %ld prevlsn: %ld\n", ptr->LSN, ptr->prevLSN);
-  return ptr;
+  return ret;
 }

src/lladd/logger/inMemoryLog.h

@@ -6,8 +6,10 @@
 int open_InMemoryLog();
 int writeLogEntry_InMemoryLog(LogEntry * e);
 lsn_t flushedLSN_InMemoryLog();
+void syncLog_InMemoryLog();
 int truncateLog_InMemoryLog(lsn_t lsn);
 lsn_t firstLogEntry_InMemoryLog();
 void close_InMemoryLog();
-LogEntry * readLSNEntry_InMemoryLog();
+LogEntry * readLSNEntry_InMemoryLog(lsn_t lsn);
+lsn_t nextEntry_InMemoryLog(const LogEntry * e);
 #endif

src/lladd/logger/logHandle.c

@@ -49,7 +49,7 @@ terms specified in this license.
    That should probably be set before calling this function.
 */
 
-static void set_offsets(LogHandle * h, const LogEntry * e, lsn_t lastRead);
+static void set_offsets(LogHandle * h, const LogEntry * e);
 
 /*-------------------------------------------------------*/
 
@@ -76,7 +76,7 @@ LogHandle getGuardedHandle(lsn_t lsn, guard_fcn_t * guard, void * guard_state) {
 const LogEntry * nextInLog(LogHandle * h) {
   const LogEntry * ret = LogReadLSN(h->next_offset);
   if(ret != NULL) {
-    set_offsets(h, ret, h->next_offset);
+    set_offsets(h, ret);
   }
 
   if(h->guard) {
@@ -93,20 +93,14 @@ const LogEntry * nextInLog(LogHandle * h) {
 const LogEntry * previousInTransaction(LogHandle * h) {
   const LogEntry * ret = NULL;
   if(h->prev_offset > 0) {
-    /* printf("A");  fflush(NULL); */
     ret = LogReadLSN(h->prev_offset);
-    set_offsets(h, ret, h->prev_offset);
+    set_offsets(h, ret);
-    /*printf("B");  fflush(NULL); */
 
     if(h->guard) {
-      /*printf("C");  fflush(NULL);*/
-
       if(!h->guard(ret, h->guard_state)) {
 	FreeLogEntry(ret);
 	ret = NULL;
       }
-      /*printf("D");  fflush(NULL);*/
-
     }
   }
 
@@ -121,14 +115,8 @@ const LogEntry * previousInTransaction(LogHandle * h) {
    logging implementation, not here.  (One possibility is to have
    readLSNEntry return it explicitly.)
 */
-static void set_offsets(LogHandle * h, const LogEntry * e, lsn_t lastRead) {
+static void set_offsets(LogHandle * h, const LogEntry * e) {
-  if(loggerType == LOG_TO_FILE) { 
+  h->next_offset = LogNextEntry(e);
-    h->next_offset = lastRead + sizeofLogEntry(e)+sizeof(lsn_t);
-  } else if(loggerType == LOG_TO_MEMORY) { 
-    h->next_offset = lastRead + 1; 
-  } else { 
-    abort();
-  }
   h->prev_offset = (e->type==CLRLOG) ? e->contents.clr.undoNextLSN : e->prevLSN ;
   
 }

src/lladd/logger/logWriter.c

@@ -74,7 +74,7 @@ static int roLogFD = 0;
 int logWriter_isDurable = 1;
 
 /**
-   @see flushedLSN()
+   @see flushedLSN_LogWriter()
 */
 static lsn_t flushedLSN_val;
 
@@ -125,8 +125,6 @@ static char * buffer;
 /** The size of the in-memory log buffer.  When the buffer is full,
     the log is synchronously flushed to disk. */
 #define BUFSIZE (1024 * 1024)
-//#define BUFSIZE (1024*96)
-//#define BUFSIZE (512)
 
 int openLogWriter() {
 
@@ -270,24 +268,8 @@ int writeLogEntry(LogEntry * e) {
 
   pthread_mutex_lock(&log_write_mutex);  
   
-  /*  if(!nextAvailableLSN) { 
-
-    LogHandle lh;
-    const LogEntry * le;
-
-    nextAvailableLSN = sizeof(lsn_t);
-    lh = getLSNHandle(nextAvailableLSN);
-
-    while((le = nextInLog(&lh))) {
-      nextAvailableLSN = le->LSN + sizeofLogEntry(le) + sizeof(lsn_t);;
-      FreeLogEntry(le);
-    }
-    }*/
-
   /* Set the log entry's LSN. */
   e->LSN = nextAvailableLSN;
-  //printf ("\nLSN: %ld\n", e->LSN);
-  //fflush(stdout);
 
   size_t nmemb = fwrite(&size, sizeof(lsn_t), 1, log);
   if(nmemb != 1) {
@@ -312,8 +294,6 @@ int writeLogEntry(LogEntry * e) {
     return LLADD_IO_ERROR;
   }
 
-  //fflush(log);
-
   pthread_mutex_lock(&log_read_mutex);
   nextAvailableLSN += (size + sizeof(lsn_t));
   pthread_mutex_unlock(&log_read_mutex);
@@ -324,11 +304,10 @@ int writeLogEntry(LogEntry * e) {
   return 0;
 }
 
-void syncLog() {
+void syncLog_LogWriter() {
   lsn_t newFlushedLSN;
 
   pthread_mutex_lock(&log_read_mutex);
-  // newFlushedLSN = ftell(log) + global_offset;
   newFlushedLSN = nextAvailableLSN;
   pthread_mutex_unlock(&log_read_mutex);
   // Wait to set the static variable until after the flush returns. 
@@ -343,7 +322,7 @@ void syncLog() {
   writeunlock(flushedLSN_lock);
 }
 
-lsn_t flushedLSN() {
+lsn_t flushedLSN_LogWriter() {
   readlock(flushedLSN_lock, 0);
   lsn_t ret = flushedLSN_val;
   readunlock(flushedLSN_lock);
@@ -352,7 +331,7 @@ lsn_t flushedLSN() {
 
 void closeLogWriter() {
   /* Get the whole thing to the disk before closing it. */
-  syncLog();  
+  syncLog_LogWriter();  
 
   fclose(log);
   close(roLogFD);
@@ -399,7 +378,7 @@ static LogEntry * readLogEntry() {
       fprintf(stderr, "\nattempt to read again produced newBytesRead = %ld, newSize was %ld\n", newBytesRead, newSize);
       fflush(stderr);
 
-      abort();  // really abort here.  This code should attempt to piece together short log reads...
+      abort();  // XXX really abort here.  This code should attempt to piece together short log reads...
     }
   }
   ret = malloc(size);
@@ -443,16 +422,16 @@ static LogEntry * readLogEntry() {
   return ret;
 }
 
-LogEntry * readLSNEntry(lsn_t LSN) {
+LogEntry * readLSNEntry_LogWriter(lsn_t LSN) {
   LogEntry * ret;
 
   /** Because we use two file descriptors to access the log, we need
       to flush the log write buffer before concluding we're at EOF. */
-  if(flushedLSN() <= LSN && LSN < nextAvailableLSN) {
+  if(flushedLSN_LogWriter() <= LSN && LSN < nextAvailableLSN) {
-    //    fprintf(stderr, "Syncing log flushed = %d, requested = %d\n", flushedLSN(), LSN);
+    //    fprintf(stderr, "Syncing log flushed = %d, requested = %d\n", flushedLSN_LogWriter(), LSN);
-    syncLog();
+    syncLog_LogWriter();
-    assert(flushedLSN() >= LSN);
+    assert(flushedLSN_LogWriter() >= LSN);
-    //    fprintf(stderr, "Synced log flushed = %d, requested = %d\n", flushedLSN(), LSN);
+    //    fprintf(stderr, "Synced log flushed = %d, requested = %d\n", flushedLSN_LogWriter(), LSN);
   }
 
   pthread_mutex_lock(&log_read_mutex);
@@ -478,7 +457,11 @@ LogEntry * readLSNEntry(lsn_t LSN) {
   
 }
 
-int truncateLog(lsn_t LSN) {
+lsn_t nextEntry_LogWriter(const LogEntry * e) { 
+  return e->LSN + sizeofLogEntry(e) + sizeof(lsn_t);
+}
+
+int truncateLog_LogWriter(lsn_t LSN) {
   FILE *tmpLog;
 
   const LogEntry * le;

src/lladd/logger/logWriter.h

@@ -93,7 +93,7 @@ int writeLogEntry(LogEntry * e);
 /**
   flush the entire log (tail) that is currently in memory to disk
 */
-void syncLog();
+void syncLog_LogWriter();
 
 /** 
    Return the highest LSN that is known to be on disk.  (Currently, we
@@ -106,7 +106,7 @@ void syncLog();
    and is less than the LSN of all log entries that might not have
    been forced to disk.
 */
-lsn_t flushedLSN();
+lsn_t flushedLSN_LogWriter();
 
 /**
    Truncates the log file.  In the single-threaded case, this works as
@@ -134,7 +134,7 @@ lsn_t flushedLSN();
 
 */
 
-int truncateLog(lsn_t);
+int truncateLog_LogWriter(lsn_t);
 
 
 /** 
@@ -163,7 +163,8 @@ void deleteLogWriter();
 
    @param LSN the LSN of the entry that will be read.
 */
-LogEntry * readLSNEntry(lsn_t LSN);
+LogEntry * readLSNEntry_LogWriter(lsn_t LSN);
+lsn_t nextEntry_LogWriter(const LogEntry * e);
 
 extern int logWriter_isDurable;
 

src/lladd/logger/logger2.c

@@ -40,32 +40,43 @@ permission to use and distribute the software in accordance with the
 terms specified in this license.
 ---*/
 
+/**
+   @file Abstract log implementation.  Provides access to methods that
+   directly read and write log entries, force the log to disk, etc.
+
+   @todo Switch logger2 to use function pointers?
+*/
+
+#include <stdio.h>
+#include <assert.h>
 #include <config.h>
+
 #include <lladd/common.h>
 
 #include <lladd/logger/logger2.h>
 #include "logWriter.h"
 #include "inMemoryLog.h"
+
 #include "page.h"  
-/*#include <lladd/bufferManager.h>*/
-#include <stdio.h>
-#include <assert.h>
 
 int loggerType = LOG_TO_FILE;
 
-void genericLogWrite(LogEntry * e) { 
+void LogWrite(LogEntry * e) { 
   if(loggerType == LOG_TO_FILE) { 
     writeLogEntry(e);
     return;
   } else if (loggerType == LOG_TO_MEMORY) {
     writeLogEntry_InMemoryLog(e);
     return;
+  } else { 
+    abort();
   }
-  abort(); // we dont have an appropriate implementation, or weren't initialized...
 }
 
 int LogInit(int logType) { 
-  assert(logType == loggerType);
+
+  loggerType = logType;
+
   if(LOG_TO_FILE == logType) { 
     openLogWriter();
   } else if(LOG_TO_MEMORY == logType) { 
@@ -73,38 +84,37 @@ int LogInit(int logType) {
   } else { 
     return -1;
   }
-  loggerType = logType;
   return 0;
 }
 
 int LogDeinit() { 
-  assert(loggerType != -1); 
   if(LOG_TO_FILE == loggerType) { 
     closeLogWriter();
   } else if(LOG_TO_MEMORY == loggerType) { 
     close_InMemoryLog();
+  } else { 
+    abort();
   }
   return 0;
 }
 
 void LogForce(lsn_t lsn) { 
+  if(LogFlushedLSN() < lsn) {
     if(LOG_TO_FILE == loggerType) { 
-    if(flushedLSN() < lsn) { 
+      syncLog_LogWriter();
-      syncLog();
-    }
-    assert(flushedLSN() >= lsn);
-    return;
     } else if (LOG_TO_MEMORY == loggerType) { 
-    assert(flushedLSN_InMemoryLog() >= lsn);
+      syncLog_InMemoryLog();
-    return;
+    } else { 
-  }
       abort();
     }
+  }
+  assert(LogFlushedLSN() >= lsn);
+}
 void LogTruncate(lsn_t lsn) { 
   if(LOG_TO_FILE == loggerType) { 
-    truncateLog(lsn);
+    truncateLog_LogWriter(lsn);
   } else if(LOG_TO_MEMORY == loggerType) { 
-    abort();
+    truncateLog_InMemoryLog(lsn);
   } else { 
     abort();
   }
@@ -113,7 +123,7 @@ void LogTruncate(lsn_t lsn) {
 
 lsn_t LogFlushedLSN() { 
   if(LOG_TO_FILE == loggerType) { 
-    return flushedLSN();
+    return flushedLSN_LogWriter();
   } else if(LOG_TO_MEMORY == loggerType) { 
     return flushedLSN_InMemoryLog();
   } 
@@ -125,31 +135,41 @@ lsn_t LogTruncationPoint() {
     return firstLogEntry();
   } else if(LOG_TO_MEMORY == loggerType) { 
     return firstLogEntry_InMemoryLog();
-  }
+  } else { 
     abort();
   }
+}
 const LogEntry * LogReadLSN(lsn_t lsn) { 
   if(LOG_TO_FILE == loggerType) { 
-    return readLSNEntry(lsn);
+    return readLSNEntry_LogWriter(lsn);
   } else if(LOG_TO_MEMORY == loggerType) { 
     return readLSNEntry_InMemoryLog(lsn);
-  } 
+  } else {
     abort();
   }
+}
+
+lsn_t LogNextEntry(const LogEntry * e) { 
+  if(LOG_TO_FILE == loggerType) { 
+    return nextEntry_LogWriter(e);
+  } else if(LOG_TO_MEMORY == loggerType) { 
+    return nextEntry_InMemoryLog(e);
+  } else {
+    abort();
+  }
+}
 
 void FreeLogEntry(const LogEntry * e) { 
   if(LOG_TO_FILE == loggerType) { 
-    free((LogEntry*)e);
+    free((void*)e);
-    return;
   } else if(LOG_TO_MEMORY == loggerType) {
-    if(e->LSN == -1) { 
+    free((void*)e);
-      free((LogEntry*)e);
+  } else { 
-    }
-    return;
-  }
     abort();
   }
 
+}
+
 TransactionLog LogTransBegin(int xid) {
   TransactionLog tl;
   tl.xid = xid;
@@ -164,7 +184,7 @@ static lsn_t LogTransCommon(TransactionLog * l, int type) {
   LogEntry * e = allocCommonLogEntry(l->prevLSN, l->xid, type);
   lsn_t ret;
 
-  genericLogWrite(e);
+  LogWrite(e);
 
   if(l->prevLSN == -1) { l->recLSN = e->LSN; }
   l->prevLSN = e->LSN;
@@ -183,7 +203,7 @@ extern int numActiveXactions;
 /**
    @todo This belongs in logWriter.c and needs a new name.
 */
-static lsn_t LogTransBundledCommit(TransactionLog * l) {
+static lsn_t groupCommit(TransactionLog * l) {
   static pthread_mutex_t check_commit = PTHREAD_MUTEX_INITIALIZER;
   static pthread_cond_t tooFewXacts = PTHREAD_COND_INITIALIZER;
   static int pendingCommits = 0;
@@ -196,7 +216,7 @@ static lsn_t LogTransBundledCommit(TransactionLog * l) {
   //  int retcode;
   
   pthread_mutex_lock(&check_commit);
-  if(flushedLSN() >= ret) {
+  if(LogFlushedLSN() >= ret) {
     pthread_mutex_unlock(&check_commit);
     return ret;
   }
@@ -215,7 +235,7 @@ static lsn_t LogTransBundledCommit(TransactionLog * l) {
   if((numActiveXactions > 1 && pendingCommits < numActiveXactions) ||
      (numActiveXactions > 20 && pendingCommits < (int)((double)numActiveXactions * 0.95))) {
     while(ETIMEDOUT != (pthread_cond_timedwait(&tooFewXacts, &check_commit, &timeout))) {
-      if(flushedLSN() >= ret) {
+      if(LogFlushedLSN() >= ret) {
 	pendingCommits--;
 	pthread_mutex_unlock(&check_commit);
 	return ret;
@@ -225,32 +245,32 @@ static lsn_t LogTransBundledCommit(TransactionLog * l) {
   } else {
     //     printf("Didn't wait %d < %d\n", (numActiveXactions / 2), pendingCommits);
   } 
-  if(flushedLSN() < ret) {
+  if(LogFlushedLSN() < ret) {
-    syncLog();
+    syncLog_LogWriter();
     syncLogCount++;
     //    printf(" %d ", syncLogCount);
     pthread_cond_broadcast(&tooFewXacts);
   }
-  assert(flushedLSN() >= ret);
+  assert(LogFlushedLSN() >= ret);
   pendingCommits--;
   pthread_mutex_unlock(&check_commit);
   return ret;
 }
 
 lsn_t LogTransCommit(TransactionLog * l) { 
-  assert(loggerType != -1);
+  return groupCommit(l);
-  if(LOG_TO_FILE == loggerType) { 
-    return LogTransBundledCommit(l);
-  } else if(LOG_TO_MEMORY == loggerType) { 
-    return LogTransCommon(l, XCOMMIT); 
-  }
-  abort();
 }
 
 lsn_t LogTransAbort(TransactionLog * l) {
   return LogTransCommon(l, XABORT);
 }
 
+
+/** 
+    @todo Does the handling of operation types / argument sizes belong
+    here?  Shouldn't it be in logEntry.c, or perhaps with other code
+    that reasons about the various operation types?
+*/
 LogEntry * LogUpdate(TransactionLog * l, Page * p, recordid rid, int operation, const byte * args) {
   void * preImage = NULL;
   long argSize  = 0;
@@ -283,7 +303,7 @@ LogEntry * LogUpdate(TransactionLog * l, Page * p, recordid rid, int operation,
   e = allocUpdateLogEntry(l->prevLSN, l->xid, operation, rid, args, argSize, preImage);
   
   //  writeLogEntry(e); 
-  genericLogWrite(e);
+  LogWrite(e);
   DEBUG("Log Common %d, LSN: %ld type: %ld (prevLSN %ld) (argSize %ld)\n", e->xid, 
 	 (long int)e->LSN, (long int)e->type, (long int)e->prevLSN, (long int) argSize);
 
@@ -298,7 +318,7 @@ LogEntry * LogUpdate(TransactionLog * l, Page * p, recordid rid, int operation,
 lsn_t LogCLR(int xid, lsn_t LSN, recordid rid, lsn_t prevLSN) { 
   lsn_t ret;
   LogEntry * e = allocCLRLogEntry(-1, xid, LSN, rid, prevLSN);
-  genericLogWrite(e);
+  LogWrite(e);
 
   DEBUG("Log CLR %d, LSN: %ld (undoing: %ld, next to undo: %ld)\n", xid, 
   	 e->LSN, LSN, prevLSN);