/** Delete rows
* Like query(), except the selected rows are deleted.
*/
void del(void *db, char **argv, int argc) {
int qargc;
void *rec = NULL;
wg_query *q;
wg_query_arg *arglist;
gint lock_id;
arglist = make_arglist(db, argv, argc, &qargc);
if(!arglist)
return;
/* Use maximum isolation */
if(!(lock_id = wg_start_write(db))) {
fprintf(stderr, "failed to get lock on database\n");
goto abrt1;
}
q = wg_make_query(db, NULL, 0, arglist, qargc);
if(!q)
goto abrt2;
if(q->res_count > 0) {
printf("Deleting %d rows...", (int) q->res_count);
rec = wg_fetch(db, q);
while(rec) {
wg_delete_record(db, (gint *) rec);
rec = wg_fetch(db, q);
}
printf(" done\n");
}
wg_free_query(db, q);
abrt2:
wg_end_write(db, lock_id);
abrt1:
free_arglist(db, arglist, qargc);
}
void run_demo(void* db) {
void *rec = NULL, *firstrec = NULL, *nextrec = NULL;
/* Pointers to a database record */
wg_int enc; /* Encoded data */
wg_int lock_id; /* Id of an acquired lock (for releasing it later) */
wg_int len;
int i;
int intdata, datedata, timedata;
char strbuf[80];
printf("********* Starting demo ************\n");
/* Begin by creating a simple record of 3 fields and fill it
* with integer data.
*/
printf("Creating first record.\n");
rec=wg_create_record(db, 3);
if (rec==NULL) {
printf("rec creation error.\n");
return;
}
/* Encode a field, checking for errors */
enc = wg_encode_int(db, 44);
if(enc==WG_ILLEGAL) {
printf("failed to encode an integer.\n");
return;
}
/* Negative return value shows that an error occurred */
if(wg_set_field(db, rec, 0, enc) < 0) {
printf("failed to store a field.\n");
return;
}
/* Skip error checking for the sake of brevity for the rest of fields */
enc = wg_encode_int(db, -199999);
wg_set_field(db, rec, 1, enc);
wg_set_field(db, rec, 2, wg_encode_int(db, 0));
/* Now examine the record we have created. Get record length,
* encoded value of each field, data type and decoded value.
*/
/* Negative return value shows an error. */
len = wg_get_record_len(db, rec);
if(len < 0) {
printf("failed to get record length.\n");
return;
}
printf("Size of created record at %p was: %d\n", rec, (int) len);
for(i=0; i<len; i++) {
printf("Reading field %d:", i);
enc = wg_get_field(db, rec, i);
if(wg_get_encoded_type(db, enc) != WG_INTTYPE) {
printf("data was of unexpected type.\n");
return;
}
intdata = wg_decode_int(db, enc);
/* No error checking here. All integers are valid. */
printf(" %d\n", intdata);
}
/* Fields can be erased by setting their value to 0 which always stands for NULL value. */
printf("Clearing field 1.\n");
wg_set_field(db, rec, 1, 0);
if(wg_get_field(db, rec, 1)==0) {
printf("Re-reading field 1 returned a 0 (NULL) field.\n");
} else {
printf("unexpected value \n");
return;
}
/* Fields can be updated with data of any type (the type is not fixed). */
printf("Updating field 0 to a floating-point number.\n");
enc = wg_encode_double(db, 56.9988);
wg_set_field(db, rec, 0, enc);
enc = wg_get_field(db, rec, 0);
if(wg_get_encoded_type(db, enc) == WG_DOUBLETYPE) {
printf("Re-reading field 0 returned %f.\n", wg_decode_double(db, enc));
} else {
printf("data was of unexpected type.\n");
return;
}
/* Create a next record. Let's assume we're in an environment where
* the database is used concurrently, so there's a need to use locking.
*/
printf("Creating second record.\n");
/* Lock id of 0 means that the operation failed */
lock_id = wg_start_write(db);
if(!lock_id) {
printf("failed to acquire lock.\n");
return;
}
/* Do the write operation we acquired the lock for. */
rec=wg_create_record(db, 6);
/* Failing to release the lock would be fatal to database operation. */
if(!wg_end_write(db, lock_id)) {
printf("failed to release lock.\n");
return;
}
if (!rec) {
printf("rec creation error.\n");
return;
}
/* Reading also requires locking./ */
lock_id = wg_start_read(db);
if(!lock_id) {
printf("failed to acquire lock.\n");
return;
}
/* Do our read operation... */
len = wg_get_record_len(db, rec);
/* ... and unlock immediately */
if(!wg_end_read(db, lock_id)) {
printf("failed to release lock.\n");
return;
}
if(len < 0) {
printf("failed to get record length.\n");
return;
}
printf("Size of created record at %p was: %d\n", rec, (int) len);
/* Let's find the first record in the database */
lock_id = wg_start_read(db);
firstrec = wg_get_first_record(db);
wg_end_read(db, lock_id);
if(!firstrec) {
printf("Failed to find first record.\n");
return;
}
printf("First record of database had address %p.\n", firstrec);
/* Let's check what the next record is to demonstrate scanning records. */
nextrec = firstrec;
lock_id = wg_start_read(db);
do {
nextrec = wg_get_next_record(db, nextrec);
if(nextrec)
printf("Next record had address %p.\n", nextrec);
} while(nextrec);
printf("Finished scanning database records.\n");
wg_end_read(db, lock_id);
/* Set fields to various values. Field 0 is not touched at all (un-
* initialized). Field 1 is set to point to another record.
*/
printf("Populating second record with data.\n");
/* Let's use the first record we found to demonstrate storing
* a link to a record in a field inside another record. */
lock_id = wg_start_write(db);
enc = wg_encode_record(db, firstrec);
wg_set_field(db, rec, 1, enc);
wg_end_write(db, lock_id);
/* Now set other fields to various data types. To keep the example shorter,
* the locking and unlocking operations are omitted (in real applications,
* this would be incorrect usage if concurrent access is expected).
*/
wg_set_field(db, rec, 2, wg_encode_str(db, "This is a char array", NULL));
wg_set_field(db, rec, 3, wg_encode_char(db, 'a'));
/* For time and date, we use current time in local timezone */
enc = wg_encode_date(db, wg_current_localdate(db));
if(enc==WG_ILLEGAL) {
printf("failed to encode date.\n");
return;
}
wg_set_field(db, rec, 4, enc);
enc = wg_encode_time(db, wg_current_localtime(db));
if(enc==WG_ILLEGAL) {
printf("failed to encode time.\n");
return;
}
wg_set_field(db, rec, 5, enc);
/* Now read and print all the fields. */
wg_print_record(db, (wg_int *) rec);
printf("\n");
/* Date and time can be handled together as a datetime object. */
datedata = wg_decode_date(db, wg_get_field(db, rec, 4));
timedata = wg_decode_time(db, wg_get_field(db, rec, 5));
wg_strf_iso_datetime(db, datedata, timedata, strbuf);
printf("Reading datetime: %s.\n", strbuf);
printf("Setting date and time to 2010-03-31, 12:59\n");
/* Update date and time to arbitrary values using wg_strp_iso_date/time */
wg_set_field(db, rec, 4,
wg_encode_date(db, wg_strp_iso_date(db, "2010-03-31")));
wg_set_field(db, rec, 5,
wg_encode_time(db, wg_strp_iso_time(db, "12:59:00.33")));
printf("Dumping the contents of the database:\n");
wg_print_db(db);
printf("********* Demo ended ************\n");
}
void run_workers(void *db, int rcnt, int wcnt) {
pt_data *pt_table;
int i, tcnt;
#ifdef HAVE_PTHREAD
int err;
void *status;
pthread_attr_t attr;
#endif
#if !defined(HAVE_PTHREAD) && !defined(_WIN32)
fprintf(stderr, "No thread support: skipping tests.\n");
return;
#endif
#ifdef HAVE_PTHREAD
pthread_attr_init(&attr);
pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_JOINABLE);
#endif
#if defined(BENCHMARK) && defined(HAVE_PTHREAD)
pthread_rwlock_init(&rwlock, NULL);
#endif
#ifdef SYNC_THREADS
#if defined(HAVE_PTHREAD)
pthread_mutex_init(&twait_mutex, NULL);
pthread_cond_init(&twait_cv, NULL);
#elif defined(_WIN32)
/* Manual reset event, initial state nonsignaled. */
twait_ev = CreateEvent(NULL, TRUE, FALSE, NULL);
#endif
#endif
tcnt = rcnt + wcnt;
pt_table = (pt_data *) malloc(tcnt * sizeof(pt_data));
if(!pt_table) {
fprintf(stderr, "Failed to allocate thread table: skipping tests.\n");
return;
}
/* Spawn the threads */
#ifdef SYNC_THREADS
twait_cnt = 0;
#endif
for(i=0; i<tcnt; i++) {
pt_table[i].db = db;
pt_table[i].threadid = i;
/* First wcnt threads are writers, the remainder readers */
if(i<wcnt) {
#if defined(HAVE_PTHREAD)
err = pthread_create(&pt_table[i].pth, &attr, writer_thread, \
(void *) &pt_table[i]);
#elif defined(_WIN32)
pt_table[i].hThread = CreateThread(NULL, 0,
(LPTHREAD_START_ROUTINE) writer_thread,
(LPVOID) &pt_table[i], 0, NULL);
#endif
} else {
#if defined(HAVE_PTHREAD)
err = pthread_create(&pt_table[i].pth, &attr, reader_thread, \
(void *) &pt_table[i]);
#elif defined(_WIN32)
pt_table[i].hThread = CreateThread(NULL, 0,
(LPTHREAD_START_ROUTINE) reader_thread,
(LPVOID) &pt_table[i], 0, NULL);
#endif
}
#if defined(HAVE_PTHREAD)
if(err) {
fprintf(stderr, "Error code from pthread_create: %d.\n", err);
#elif defined(_WIN32)
if(!pt_table[i].hThread) {
/* XXX: GetLastError() gives the error code if needed */
fprintf(stderr, "CreateThread failed.\n");
#endif
goto workers_done;
}
}
#ifdef SYNC_THREADS
/* Check that all workers have entered wait state */
for(;;) {
/* While reading a word from memory is atomic, we
* still use the mutex because we want to guarantee
* that the last thread has called pthread_cond_wait().
* With Win32 API, condition variables with similar
* functionality are available starting from Windows Vista,
* so this implementation uses a simple synchronization
* event instead. This causes small, probably non-relevant
* loss in sync accuracy.
*/
#ifdef HAVE_PTHREAD
pthread_mutex_lock(&twait_mutex);
#endif
if(twait_cnt >= tcnt) break;
#ifdef HAVE_PTHREAD
pthread_mutex_unlock(&twait_mutex);
#endif
}
/* Now wake up all threads */
#if defined(HAVE_PTHREAD)
pthread_cond_broadcast(&twait_cv);
pthread_mutex_unlock(&twait_mutex);
#elif defined(_WIN32)
SetEvent(twait_ev);
#endif
#endif /* SYNC_THREADS */
/* Join the workers (wait for them to complete) */
for(i=0; i<tcnt; i++) {
#if defined(HAVE_PTHREAD)
err = pthread_join(pt_table[i].pth, &status);
if(err) {
fprintf(stderr, "Error code from pthread_join: %d.\n", err);
break;
}
#elif defined(_WIN32)
WaitForSingleObject(pt_table[i].hThread, INFINITE);
CloseHandle(pt_table[i].hThread);
#endif
}
workers_done:
#ifdef HAVE_PTHREAD
pthread_attr_destroy(&attr);
#endif
#if defined(BENCHMARK) && defined(HAVE_PTHREAD)
pthread_rwlock_destroy(&rwlock);
#endif
#ifdef SYNC_THREADS
#if defined(HAVE_PTHREAD)
pthread_mutex_destroy(&twait_mutex);
pthread_cond_destroy(&twait_cv);
#elif defined(_WIN32)
CloseHandle(twait_ev);
#endif
#endif
free(pt_table);
}
/** Writer thread
* Runs preconfigured number of basic write transactions
*/
worker_t writer_thread(void * threadarg) {
void * db;
int threadid, i, j, cksum;
void *rec = NULL, *frec = NULL;
db = ((pt_data *) threadarg)->db;
threadid = ((pt_data *) threadarg)->threadid;
#ifdef CHATTY_THREADS
fprintf(stdout, "Writer thread %d started.\n", threadid);
#endif
#ifdef SYNC_THREADS
/* Increment the thread counter to inform the caller
* that we are entering wait state.
*/
#ifdef HAVE_PTHREAD
pthread_mutex_lock(&twait_mutex);
#endif
twait_cnt++;
#if defined(HAVE_PTHREAD)
pthread_cond_wait(&twait_cv, &twait_mutex);
pthread_mutex_unlock(&twait_mutex);
#elif defined(_WIN32)
WaitForSingleObject(twait_ev, INFINITE);
#endif
#endif /* SYNC_THREADS */
frec = wg_get_first_record(db);
for(i=0; i<WORKLOAD; i++) {
wg_int c=-1, lock_id;
#if defined(BENCHMARK) && defined(HAVE_PTHREAD)
pthread_rwlock_wrlock(&rwlock);
#else
/* Start transaction */
if(!(lock_id = wg_start_write(db))) {
fprintf(stderr, "Writer thread %d: wg_start_write failed.\n", threadid);
goto writer_done;
}
#endif
/* Fetch checksum */
cksum = wg_decode_int(db, wg_get_field(db, frec, 0));
/* Fetch record from database */
if(i) rec = wg_get_next_record(db, rec);
else rec = frec;
if(!rec) {
fprintf(stderr, "Writer thread %d: wg_get_next_record failed.\n", threadid);
#if defined(BENCHMARK) && defined(HAVE_PTHREAD)
pthread_rwlock_unlock(&rwlock);
#else
wg_end_write(db, lock_id);
#endif
goto writer_done;
}
/* Modify record */
if(i) j = 0;
else j = 1;
for(; j<REC_SIZE; j++) {
if (wg_set_int_field(db, rec, j, c--) != 0) {
fprintf(stderr, "Writer thread %d: int storage error.\n", threadid);
#if defined(BENCHMARK) && defined(HAVE_PTHREAD)
pthread_rwlock_unlock(&rwlock);
#else
wg_end_write(db, lock_id);
#endif
goto writer_done;
}
}
/* Update checksum */
wg_set_int_field(db, frec, 0, ++cksum);
#if defined(BENCHMARK) && defined(HAVE_PTHREAD)
pthread_rwlock_unlock(&rwlock);
#else
/* End transaction */
if(!wg_end_write(db, lock_id)) {
fprintf(stderr, "Writer thread %d: wg_end_write failed.\n", threadid);
goto writer_done;
}
#endif
}
#ifdef CHATTY_THREADS
fprintf(stdout, "Writer thread %d ended.\n", threadid);
#endif
writer_done:
#if defined(HAVE_PTHREAD)
pthread_exit(NULL);
#elif defined(_WIN32)
return 0;
#endif
}
static char* insert(thread_data_p tdata, char* inparams[], char* invalues[], int incount) {
char* database=tdata->database;
char *token=NULL;
int i,tmp;
//int j,x;
char* json=NULL;
//int count=MAXCOUNT;
void* db=NULL; // actual database pointer
//void* rec;
char* res;
wg_int lock_id=0; // non-0 iff lock set
char errbuf[ERRBUF_LEN]; // used for building variable-content input param error strings only
// yajl
/*
yajl_handle hand;
yajl_gen g;
yajl_status stat;
size_t rd;
int retval = 0;
int a = 1;
*/
// -------check and parse cgi parameters, attach database ------------
// set printing params to defaults
tdata->format=1; // 1: json
tdata->maxdepth=MAX_DEPTH_DEFAULT; // rec depth limit for printer
tdata->showid=0; // add record id as first extra elem: 0: no, 1: yes
tdata->strenc=2; // string special chars escaping: 0: just ", 1: urlencode, 2: json, 3: csv
// find ids and display format parameters
for(i=0;i<incount;i++) {
if (strncmp(inparams[i],"rec",MAXQUERYLEN)==0) {
json=invalues[i];
} else {
// handle generic parameters for all queries: at end of param check
res=handle_generic_param(tdata,inparams[i],invalues[i],&token,errbuf);
if (res!=NULL) return res; // return error string
}
}
if (json==NULL || strlen(json)==0) {
return errhalt(MISSING_JSON_ERR,tdata);
}
// authorization
if (!authorize(WRITE_LEVEL,tdata,database,token)) {
return errhalt(NOT_AUTHORIZED_ERR,tdata);
}
// all parameters and values were understood
if (tdata->format==0) {
// csv
tdata->maxdepth=0; // record structure not printed for csv
tdata->strenc=3; // only " replaced with ""
}
// attach to database
db=op_attach_database(tdata,database,READ_LEVEL);
if (!db) {
if (!authorize(ADMIN_LEVEL,tdata,database,token)) {
return errhalt(NOT_AUTHORIZED_INSERT_CREATE_ERR,tdata);
} else {
if (tdata->realthread && tdata->common->shutdown) return NULL; // for multithreading only
db=op_create_database(tdata,database,0);
if (!db) return err_clear_detach_halt(DB_CREATE_ERR,tdata);
}
}
// database attached OK
// create output string buffer (may be reallocated later)
tdata->buf=str_new(INITIAL_MALLOC);
if (tdata->buf==NULL) return errhalt(MALLOC_ERR,tdata);
tdata->bufsize=INITIAL_MALLOC;
tdata->bufptr=tdata->buf;
op_print_data_start(tdata,1);
// initialize yajl
/*
g = yajl_gen_alloc(NULL);
yajl_gen_config(g, yajl_gen_beautify, 0);
yajl_gen_config(g, yajl_gen_validate_utf8, 1);
hand = yajl_alloc(&callbacks, NULL, (void *) g);
yajl_config(hand, yajl_allow_comments, 1);
*/
// take a write lock
if (tdata->realthread && tdata->common->shutdown) return NULL; // for multithreading only
lock_id = wg_start_write(db); // get write lock
tdata->lock_id=lock_id;
tdata->lock_type=WRITE_LOCK_TYPE;
if (!lock_id) return err_clear_detach_halt(LOCK_ERR,tdata);
// start parsing
/*
rd=strlen(json);
stat = yajl_parse(hand, json, rd);
if (stat==yajl_status_ok) stat=yajl_complete_parse(hand);
if (stat != yajl_status_ok) {
unsigned char * str = yajl_get_error(hand, 1, json, rd);
fprintf(stderr, "%s", (const char *) str);
yajl_free_error(hand, str);
retval = 1;
} else {
// parse succeeded
const unsigned char * buf;
size_t len;
yajl_gen_get_buf(g, &buf, &len);
fwrite(buf, 1, len, stdout);
yajl_gen_clear(g);
}
yajl_gen_free(g);
yajl_free(hand);
*/
// parsing ended
// parse json and insert
tmp=wg_parse_json_document(db,json);
if(tmp==-1) {
return err_clear_detach_halt(JSON_ERR,tdata);
} else if(tmp==-2) {
return err_clear_detach_halt(INCONSISTENT_ERR,tdata);
}
if(!str_guarantee_space(tdata,MIN_STRLEN))
return err_clear_detach_halt(MALLOC_ERR,tdata);
strcpy(tdata->bufptr,"1");
tdata->bufptr+=strlen("1");
// end activity
if (!wg_end_write(db, lock_id)) { // release write lock
return err_clear_detach_halt(LOCK_RELEASE_ERR,tdata);
}
tdata->lock_id=0;
op_detach_database(tdata,db);
if(!op_print_data_end(tdata,1))
return err_clear_detach_halt(MALLOC_ERR,tdata);
return tdata->buf;
}
static char* drop(thread_data_p tdata, char* inparams[], char* invalues[], int incount) {
char* database=tdata->database;
char *token=NULL;
int i,tmp;
void* db=NULL; // actual database pointer
char *res;
int lock_id=0;
int found=0;
char errbuf[ERRBUF_LEN];
// find and check parameters
for(i=0;i<incount;i++) {
if (strncmp(inparams[i],"db",MAXQUERYLEN)==0) {
database=invalues[i];
if(database==NULL || strlen(database)<1 || atoi(database)<=0) {
return errhalt(DB_NAME_ERR,tdata);
}
} else {
// handle generic parameters for all queries: at end of param check
res=handle_generic_param(tdata,inparams[i],invalues[i],&token,errbuf);
if (res!=NULL) return res; // return error string
}
}
// authorization
if (!authorize(ADMIN_LEVEL,tdata,database,token)) {
return errhalt(NOT_AUTHORIZED_ERR,tdata);
}
// all parameters and values were understood
// create output string buffer (may be reallocated later)
tdata->buf=str_new(INITIAL_MALLOC);
if (tdata->buf==NULL) return errhalt(MALLOC_ERR,tdata);
tdata->bufsize=INITIAL_MALLOC;
tdata->bufptr=tdata->buf;
op_print_data_start(tdata,0);
// check if access allowed in the conf file
if (database!=NULL && (tdata->global)->conf->dbases.used>0) {
for(i=0;i<(tdata->global)->conf->dbases.used;i++) {
if (!strcmp(database,(tdata->global)->conf->dbases.vals[i])) {
found=1;
break;
}
}
if (!found) return errhalt(DB_AUTHORIZE_ERR,tdata);
}
// first try to attach to an existing database
db=op_attach_database(tdata,database,ADMIN_LEVEL);
if (db==NULL) {
return errhalt(DB_NOT_EXISTS_ERR,tdata);
} else {
// database exists, take lock
if (tdata->realthread && tdata->common->shutdown) return NULL; // for multithreading only
tdata->db=db;
lock_id = wg_start_write(db); // get write lock
tdata->lock_id=lock_id;
tdata->lock_type=WRITE_LOCK_TYPE;
if (!lock_id) return err_clear_detach_halt(LOCK_ERR,tdata);
tmp=wg_detach_database(db); // detaches a database: returns 0 if OK
if (tmp) return err_clear_detach_halt(DB_DROP_ERR,tdata);
tmp=wg_delete_database(database);
if (tmp) return errhalt(DB_DROP_ERR,tdata);
}
// deleted successfully
tdata->db=NULL;
tdata->lock_id=0;
if(!str_guarantee_space(tdata,MIN_STRLEN))
return err_clear_detach_halt(MALLOC_ERR,tdata);
strcpy(tdata->bufptr,"1");
tdata->bufptr+=strlen("1");
// end activity
if(!op_print_data_end(tdata,0))
return errhalt(MALLOC_ERR,tdata);
return tdata->buf;
}
