persistentstorage/sqlite3api/TEST/TclScript/threadtest1.c
changeset 0 08ec8eefde2f
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/persistentstorage/sqlite3api/TEST/TclScript/threadtest1.c	Fri Jan 22 11:06:30 2010 +0200
@@ -0,0 +1,289 @@
+/*
+** 2002 January 15
+**
+** The author disclaims copyright to this source code.  In place of
+** a legal notice, here is a blessing:
+**
+**    May you do good and not evil.
+**    May you find forgiveness for yourself and forgive others.
+**    May you share freely, never taking more than you give.
+**
+*************************************************************************
+** This file implements a simple standalone program used to test whether
+** or not the SQLite library is threadsafe.
+**
+** Testing the thread safety of SQLite is difficult because there are very
+** few places in the code that are even potentially unsafe, and those
+** places execute for very short periods of time.  So even if the library
+** is compiled with its mutexes disabled, it is likely to work correctly
+** in a multi-threaded program most of the time.  
+**
+** This file is NOT part of the standard SQLite library.  It is used for
+** testing only.
+*/
+#include "sqlite.h"
+#include <pthread.h>
+#include <sched.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+/*
+** Enable for tracing
+*/
+static int verbose = 0;
+
+/*
+** Come here to die.
+*/
+static void Exit(int rc){
+  exit(rc);
+}
+
+extern char *sqlite3_mprintf(const char *zFormat, ...);
+extern char *sqlite3_vmprintf(const char *zFormat, va_list);
+
+/*
+** When a lock occurs, yield.
+*/
+static int db_is_locked(void *NotUsed, int iCount){
+  /* sched_yield(); */
+  if( verbose ) printf("BUSY %s #%d\n", (char*)NotUsed, iCount);
+  usleep(100);
+  return iCount<25;
+}
+
+/*
+** Used to accumulate query results by db_query()
+*/
+struct QueryResult {
+  const char *zFile;  /* Filename - used for error reporting */
+  int nElem;          /* Number of used entries in azElem[] */
+  int nAlloc;         /* Number of slots allocated for azElem[] */
+  char **azElem;      /* The result of the query */
+};
+
+/*
+** The callback function for db_query
+*/
+static int db_query_callback(
+  void *pUser,     /* Pointer to the QueryResult structure */
+  int nArg,        /* Number of columns in this result row */
+  char **azArg,    /* Text of data in all columns */
+  char **NotUsed   /* Names of the columns */
+){
+  struct QueryResult *pResult = (struct QueryResult*)pUser;
+  int i;
+  if( pResult->nElem + nArg >= pResult->nAlloc ){
+    if( pResult->nAlloc==0 ){
+      pResult->nAlloc = nArg+1;
+    }else{
+      pResult->nAlloc = pResult->nAlloc*2 + nArg + 1;
+    }
+    pResult->azElem = realloc( pResult->azElem, pResult->nAlloc*sizeof(char*));
+    if( pResult->azElem==0 ){
+      fprintf(stdout,"%s: malloc failed\n", pResult->zFile);
+      return 1;
+    }
+  }
+  if( azArg==0 ) return 0;
+  for(i=0; i<nArg; i++){
+    pResult->azElem[pResult->nElem++] =
+        sqlite3_mprintf("%s",azArg[i] ? azArg[i] : ""); 
+  }
+  return 0;
+}
+
+/*
+** Execute a query against the database.  NULL values are returned
+** as an empty string.  The list is terminated by a single NULL pointer.
+*/
+char **db_query(sqlite *db, const char *zFile, const char *zFormat, ...){
+  char *zSql;
+  int rc;
+  char *zErrMsg = 0;
+  va_list ap;
+  struct QueryResult sResult;
+  va_start(ap, zFormat);
+  zSql = sqlite3_vmprintf(zFormat, ap);
+  va_end(ap);
+  memset(&sResult, 0, sizeof(sResult));
+  sResult.zFile = zFile;
+  if( verbose ) printf("QUERY %s: %s\n", zFile, zSql);
+  rc = sqlite3_exec(db, zSql, db_query_callback, &sResult, &zErrMsg);
+  if( rc==SQLITE_SCHEMA ){
+    if( zErrMsg ) free(zErrMsg);
+    rc = sqlite3_exec(db, zSql, db_query_callback, &sResult, &zErrMsg);
+  }
+  if( verbose ) printf("DONE %s %s\n", zFile, zSql);
+  if( zErrMsg ){
+    fprintf(stdout,"%s: query failed: %s - %s\n", zFile, zSql, zErrMsg);
+    free(zErrMsg);
+    free(zSql);
+    Exit(1);
+  }
+  sqlite3_free(zSql);
+  if( sResult.azElem==0 ){
+    db_query_callback(&sResult, 0, 0, 0);
+  }
+  sResult.azElem[sResult.nElem] = 0;
+  return sResult.azElem;
+}
+
+/*
+** Execute an SQL statement.
+*/
+void db_execute(sqlite *db, const char *zFile, const char *zFormat, ...){
+  char *zSql;
+  int rc;
+  char *zErrMsg = 0;
+  va_list ap;
+  va_start(ap, zFormat);
+  zSql = sqlite3_vmprintf(zFormat, ap);
+  va_end(ap);
+  if( verbose ) printf("EXEC %s: %s\n", zFile, zSql);
+  do{
+    rc = sqlite3_exec(db, zSql, 0, 0, &zErrMsg);
+  }while( rc==SQLITE_BUSY );
+  if( verbose ) printf("DONE %s: %s\n", zFile, zSql);
+  if( zErrMsg ){
+    fprintf(stdout,"%s: command failed: %s - %s\n", zFile, zSql, zErrMsg);
+    free(zErrMsg);
+    sqlite3_free(zSql);
+    Exit(1);
+  }
+  sqlite3_free(zSql);
+}
+
+/*
+** Free the results of a db_query() call.
+*/
+void db_query_free(char **az){
+  int i;
+  for(i=0; az[i]; i++){
+    sqlite3_free(az[i]);
+  }
+  free(az);
+}
+
+/*
+** Check results
+*/
+void db_check(const char *zFile, const char *zMsg, char **az, ...){
+  va_list ap;
+  int i;
+  char *z;
+  va_start(ap, az);
+  for(i=0; (z = va_arg(ap, char*))!=0; i++){
+    if( az[i]==0 || strcmp(az[i],z)!=0 ){
+      fprintf(stdout,"%s: %s: bad result in column %d: %s\n",
+        zFile, zMsg, i+1, az[i]);
+      db_query_free(az);
+      Exit(1);
+    }
+  }
+  va_end(ap);
+  db_query_free(az);
+}
+
+pthread_mutex_t lock = PTHREAD_MUTEX_INITIALIZER;
+pthread_cond_t sig = PTHREAD_COND_INITIALIZER;
+int thread_cnt = 0;
+
+static void *worker_bee(void *pArg){
+  const char *zFilename = (char*)pArg;
+  char *azErr;
+  int i, cnt;
+  int t = atoi(zFilename);
+  char **az;
+  sqlite *db;
+
+  pthread_mutex_lock(&lock);
+  thread_cnt++;
+  pthread_mutex_unlock(&lock);
+  printf("%s: START\n", zFilename);
+  fflush(stdout);
+  for(cnt=0; cnt<10; cnt++){
+    sqlite3_open(&zFilename[2], &db);
+    if( db==0 ){
+      fprintf(stdout,"%s: can't open\n", zFilename);
+      Exit(1);
+    }
+    sqlite3_busy_handler(db, db_is_locked, zFilename);
+    db_execute(db, zFilename, "CREATE TABLE t%d(a,b,c);", t);
+    for(i=1; i<=100; i++){
+      db_execute(db, zFilename, "INSERT INTO t%d VALUES(%d,%d,%d);",
+         t, i, i*2, i*i);
+    }
+    az = db_query(db, zFilename, "SELECT count(*) FROM t%d", t);
+    db_check(zFilename, "tX size", az, "100", 0);  
+    az = db_query(db, zFilename, "SELECT avg(b) FROM t%d", t);
+    db_check(zFilename, "tX avg", az, "101", 0);  
+    db_execute(db, zFilename, "DELETE FROM t%d WHERE a>50", t);
+    az = db_query(db, zFilename, "SELECT avg(b) FROM t%d", t);
+    db_check(zFilename, "tX avg2", az, "51", 0);
+    for(i=1; i<=50; i++){
+      char z1[30], z2[30];
+      az = db_query(db, zFilename, "SELECT b, c FROM t%d WHERE a=%d", t, i);
+      sprintf(z1, "%d", i*2);
+      sprintf(z2, "%d", i*i);
+      db_check(zFilename, "readback", az, z1, z2, 0);
+    }
+    db_execute(db, zFilename, "DROP TABLE t%d;", t);
+    sqlite3_close(db);
+  }
+  printf("%s: END\n", zFilename);
+  /* unlink(zFilename); */
+  fflush(stdout);
+  pthread_mutex_lock(&lock);
+  thread_cnt--;
+  if( thread_cnt<=0 ){
+    pthread_cond_signal(&sig);
+  }
+  pthread_mutex_unlock(&lock);
+  return 0;
+}
+
+int main(int argc, char **argv){
+  char *zFile;
+  int i, n;
+  pthread_t id;
+  if( argc>2 && strcmp(argv[1], "-v")==0 ){
+    verbose = 1;
+    argc--;
+    argv++;
+  }
+  if( argc<2 || (n=atoi(argv[1]))<1 ) n = 10;
+  for(i=0; i<n; i++){
+    char zBuf[200];
+    sprintf(zBuf, "testdb-%d", (i+1)/2);
+    unlink(zBuf);
+  }
+  for(i=0; i<n; i++){
+    zFile = sqlite3_mprintf("%d.testdb-%d", i%2+1, (i+2)/2);
+    if( (i%2)==0 ){
+      /* Remove both the database file and any old journal for the file
+      ** being used by this thread and the next one. */
+      char *zDb = &zFile[2];
+      char *zJournal = sqlite3_mprintf("%s-journal", zDb);
+      unlink(zDb);
+      unlink(zJournal);
+      free(zJournal);
+    }
+      
+    pthread_create(&id, 0, worker_bee, (void*)zFile);
+    pthread_detach(id);
+  }
+  pthread_mutex_lock(&lock);
+  while( thread_cnt>0 ){
+    pthread_cond_wait(&sig, &lock);
+  }
+  pthread_mutex_unlock(&lock);
+  for(i=0; i<n; i++){
+    char zBuf[200];
+    sprintf(zBuf, "testdb-%d", (i+1)/2);
+    unlink(zBuf);
+  }
+  return 0;
+}