shithub: purgatorio

ref: 60ecd07e6d3f5786c8723dc9172c35d580fdadc8
dir: /tools/db/infdb.c/

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//
//	infdb - NT data base daemon for Inferno
//
//	Copyright 1997 Lucent Technologies
//
//	May 1997
//
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <fcntl.h>
#ifdef WIN32
#include <winsock.h>
#include <SQL.h>
#include <SQLEXT.h>
#else
#include <unistd.h>
#include <sql.h>
#include <sqlext.h>
#define max(a, b)        ((a) > (b) ? (a) : (b))
#define strnicmp strncasecmp
#endif

#define MAXCOLS	100
#define BUFSIZE	8192
#define REQ_HEADER_SIZE 18
#define RES_HEADER_SIZE 22
#define OFFSET_LENGTH 2
#define OFFSET_STREAM 14
#define OFFSET_REQ_DATA 18
#define OFFSET_RETURN 18
#define OFFSET_RES_DATA 22

#define	CONN_ALLOC_FAIL		1
#define STREAM_ALLOC_FAIL	2
#define STREAM_BAD_ID		3
#define LAST_ERROR_NO		4


//
//	Deal with one connection.  Use stdin and stdout to read and write messages.
//  Each incoming message is answered before reading the next incoming message.
//

typedef int STATUS;
#define			OK		 0
#define			WARN	-1
#define			ERR		-2

typedef struct {
	int		state;
#define			SQLC_FREE	0
#define			SQLC_INUSE	1
	int		connid;
	int		refcount;
	UCHAR	user[48];
	UCHAR	passwd[48];
	UCHAR	dbname[48];
	UCHAR	errmsg[256];
	HDBC	hdbc;
} SQLConn;


typedef struct {
	int		state;
#define			SQLS_FREE	0
#define			SQLS_INUSE	1
	int		streamid;
	int		connid;
	HSTMT	hstmt;
	UCHAR	errmsg[256];
	UCHAR	colname[MAXCOLS][32];
	SWORD	coltype[MAXCOLS];
	SWORD	colnamelen;
	SWORD	nullable;
	UDWORD	collen[MAXCOLS];
	SWORD	scale;
	SDWORD	outlen[MAXCOLS];
	UCHAR	*data[MAXCOLS];
	SWORD	nresultcols;
	SDWORD	rowcount;
	SWORD	rownum;
	RETCODE	rc;
	UCHAR	*setdata[MAXCOLS];
	SDWORD	setdatalen[MAXCOLS];
} SQLStream;


typedef struct {
	HENV		henv;
	int			maxconn;
	int			numconn;
	SQLConn		**scarray;
	int			maxstream;
	int			numstream;
	SQLStream	**ssarray;
} SQLEnv;


typedef struct {
	char	mtype;
	char	version;
	int		nbytes;
	int		sstream;
	int		retcode;
	int		bytesNotRead;
	char	*data;
} DBMSG, *DBMSGP;


int			getCommand		(DBMSGP msgp, UCHAR *buf, int bufsiz);
void		sendResponse	(char type, int lendata, int sstream, int retcode, char *data);
void		sendError		(char *errmsg, int sstream);
void		print_err		(SQLEnv *sqle, int connid, int streamid, UCHAR * buf, int bufsiz);
UDWORD		display_size	(SWORD coltype, UDWORD collen, UCHAR *colname);

STATUS		newSqlEnv		(SQLEnv **sqle);
STATUS		freeSqlEnv		(SQLEnv **sqle);

STATUS		newSqlConn		(SQLEnv *sqle, char *info, int *connid);
STATUS		mapSqlConn		(SQLEnv *sqle, int connid, SQLConn **sqlc);
STATUS		freeSqlConn		(SQLEnv *sqle, int connid);

STATUS		newSqlStream	(SQLEnv *sqle, int connid, int *streamid);
STATUS		mapSqlStream	(SQLEnv *sqle, int streamid, SQLStream **sqls);
STATUS		freeSqlStream	(SQLEnv *sqle, int streamid);

STATUS		parseConnInfo	(SQLConn *sqlc, char *info);

char	*iError[] = {
	"INFDB: DB connection allocation failed",
	"INFDB: couldn't allocate SQL stream",
	"INFDB: bad SQL stream identifier"
};

int
main(int argc, char *argv[])
{
	int			i;
	int			notdone = 1;
	int			infErrno;
	DBMSG		msg;
	SQLEnv		*sqle = NULL;
	SQLStream	*sqls;
	char		buf[BUFSIZE];
	char		outbuf[BUFSIZE];
	char		errmsg[256];
	STATUS		rc;

 	//	We just have to talk to stdin and stdout.  However, stdout may be open
	//	in text mode, which is bad for data.  Set it to binary mode.

#ifdef WIN32
	_setmode(0, _O_BINARY);
	_setmode(1, _O_BINARY);
#endif

	rc = newSqlEnv(&sqle);
	if ( rc != OK ) {
		sendError("INFDB: Failed to allocate SQL environment.", -1);
		return -1;
	}

    while ( notdone ) {
		int		bytesRead;

		bytesRead = 0;
		if ( (bytesRead = getCommand(&msg, buf, sizeof(buf))) <= 0 ) {
			continue;
		}
		msg.retcode = 0;
		infErrno = 0;

		switch ( msg.mtype ) {
		  // Initiate a new connection.
		  case 'I':
		  {
			int connid;

			rc = newSqlConn(sqle, msg.data, &connid);
			if ( rc != OK ) {
				infErrno = CONN_ALLOC_FAIL;
				break;
			}
			/*
			// Need a new SQLStream to make subsequent requests.
			rc = newSqlStream(sqle, connid, &streamid);
			if ( rc != OK )	{
				infErrno = STREAM_ALLOC_FAIL;
				break;
		    }

			sprintf(outbuf, "%d", streamid);
			*/
			sprintf(outbuf, "%d", connid);
			sendResponse('i', strlen(outbuf), msg.sstream, 0, outbuf);
			break;
		  }


		  case 'O':
		  {
			// open an SQL stream.
			int connid, streamid;

			connid = atoi(msg.data);
			rc = newSqlStream(sqle, connid, &streamid);
			if (rc != OK) {
				infErrno = STREAM_ALLOC_FAIL;
				break;
			}

			sprintf(outbuf, "%d", streamid);
			sendResponse('o', strlen(outbuf), msg.sstream, 0, outbuf);
			break;
		  }


		  case 'K':
			// klose an SQL stream
			rc = freeSqlStream(sqle, msg.sstream);
			sendResponse('k', 0, msg.sstream, 0, "");
			break;


		  case 'C': 
			// request number of columns
			rc = mapSqlStream(sqle, msg.sstream, &sqls);
			if ( rc != OK ) {
				infErrno = STREAM_BAD_ID;
				break;
			}

			sprintf(outbuf, "%d", sqls->nresultcols);
			sendResponse('c', strlen(outbuf), msg.sstream, 0, outbuf);
			break;


		  case 'N':																		 
			// fetch next row
			rc = mapSqlStream(sqle, msg.sstream, &sqls);
			if ( rc != OK ) {
				infErrno = STREAM_BAD_ID;
				break;
			}
		
			sqls->errmsg[0] = '\0';
			rc = SQLFetch(sqls->hstmt);
			if ( rc == SQL_SUCCESS || rc == SQL_SUCCESS_WITH_INFO ) {
				sqls->rownum++;
				//	if ( rc == SQL_SUCCESS_WITH_INFO ) {
					//	fprintf(stderr, "SQLFetch got SQL_SUCCESS_WITH_INFO\n");
				//	}
				/*		Get the data for all columns	*/
				for ( i = 0; i < sqls->nresultcols; i++ ) {
					rc = SQLGetData(sqls->hstmt, (UWORD)(i+1),
									(sqls->coltype[i] == SQL_LONGVARBINARY ||
									 sqls->coltype[i] == SQL_LONGVARCHAR) ? SQL_C_DEFAULT :
																			SQL_C_CHAR,
									sqls->data[i], sqls->collen[i], &sqls->outlen[i]);
					if ( rc == SQL_SUCCESS_WITH_INFO &&
											(UDWORD) sqls->outlen[i] > sqls->collen[i] ) {
						UCHAR	*tmp;

						tmp = (UCHAR *) realloc(sqls->data[i], sqls->outlen[i]+1);
						if ( tmp != NULL ) {
							SDWORD	dummy;
							sqls->data[i] = tmp;
							rc = SQLGetData(sqls->hstmt, (UWORD)(i+1), SQL_C_DEFAULT,
											&tmp[sqls->collen[i]], sqls->outlen[i], &dummy);
							sqls->collen[i] = sqls->outlen[i];
							sqls->data[i][sqls->outlen[i]] = 0;
						}
					}
					else if ( rc != SQL_SUCCESS ) {
						sprintf(sqls->errmsg, "Problem retrieving data from data base, col %d", i+1);
						msg.retcode = 2;
					}
				}
			}
			else if ( rc == SQL_NO_DATA_FOUND ) {
				sqls->rownum = 0;
				msg.retcode = 1;
			}
			else {
				sqls->rownum = -1;
				//	Probably should get some status from ODBC for message
				sprintf(sqls->errmsg, "Error occurred in fetching data");
			}
			if ( sqls->rownum < 0 ) {
				sendError(errmsg, msg.sstream);
			}
			else {
				sprintf(outbuf, "%d", sqls->rownum);
				//	rownum should be <= rowcount
				sendResponse('n', strlen(outbuf), msg.sstream, msg.retcode, outbuf);
			}
			break;


		  case 'H':
			// request an error message, if any
			rc = mapSqlStream(sqle, msg.sstream, &sqls);
			if ( rc != OK ) {
				infErrno = STREAM_BAD_ID;
				break;
			}
		
			sendError(sqls->errmsg, msg.sstream);
			sqls->errmsg[0] = 0;
			break;


		  case 'P':
			// request write data
			// in Inferno, param nums start at 0; in ODBC/SQL, they start at 1
			// This leaves outdatalen[0] unused, hence available as final SQLBindParameter arg.
			rc = mapSqlStream(sqle, msg.sstream, &sqls);
			if ( rc != OK ) {
				infErrno = STREAM_BAD_ID;
				break;
			}
		
			sqls->errmsg[0] = 0;
			if ( (i = atoi(msg.data) + 1) < 1 || i >= MAXCOLS ) {
				sendError("Illegal param number", msg.sstream);
			}
			else {
				int		len;
				char	*p = msg.data + 4;		// data points to param number

				len = msg.nbytes - 4;			// number of data chars
				if ( len < 0 ) {
					sendError("Write phase error II", msg.sstream);
					break;
				}
				if ( sqls->setdata[i] != NULL ) {
					free(sqls->setdata[i]);
				}
				sqls->setdata[i] = (char *) malloc(len + 1);
				if ( sqls->setdata[i] == NULL ) {
					sendError("Allocation error in server", msg.sstream);
					break;
				}
				//	Copy data we have into buffer, and if we don't have it all yet,
				//	try to get the rest.
				sqls->setdatalen[i] = len++;		// adjust len for trailing \n
				bytesRead = &buf[bytesRead] - p;	// number data bytes we have read
				memcpy(sqls->setdata[i], p, bytesRead);
				len -= bytesRead;					// number bytes still to read,
				while ( len > 0 ) {
					int	n;

					if ( (n = read(0, sqls->setdata[i] + bytesRead, len)) <= 0 ) {
						break;
					}
					bytesRead += n;
					len -= n;
				}
				if ( len > 0 ) {
					sendError("Couldn't read all of parameter", msg.sstream);
					break;
				}
				rc = SQLBindParameter(sqls->hstmt, (UWORD)i, SQL_PARAM_INPUT,
									SQL_C_BINARY, SQL_LONGVARBINARY,
									sqls->setdatalen[i], 0, (PTR) i, 0, sqls->setdatalen);
				if ( rc != SQL_SUCCESS ) {
					sendError("BindParameter failed: maybe not supported", msg.sstream);
					break;
				}
				sqls->setdatalen[0] = SQL_LEN_DATA_AT_EXEC(0);
				sprintf(outbuf, "%d", bytesRead - 1);
				sendResponse('p', strlen(outbuf), msg.sstream, 0, outbuf);
			}
			break;


		  case 'R':
			// request read data
			rc = mapSqlStream(sqle, msg.sstream, &sqls);
			if ( rc != OK ) {
				infErrno = STREAM_BAD_ID;
				break;
			}
		
			if ( (i = atoi(msg.data)) < 0 || i >= sqls->nresultcols || sqls->rownum <= 0 ) {
				sendError(sqls->rownum <= 0 ? "No current row" : "Illegal column number", msg.sstream);
			}
			else if ( sqls->outlen[i] == SQL_NULL_DATA || sqls->outlen[i] == SQL_NO_TOTAL ) {
				sendResponse('r', 0, msg.sstream, 0, "");
			}
			else {
				if ( sqls->coltype[i] == SQL_VARCHAR ) {
					sqls->outlen[i] = strlen(sqls->data[i]);
				}
				sendResponse('r', sqls->outlen[i], msg.sstream, 0, sqls->data[i]);
			}
			break;


		  case 'T':
			// request column title
			rc = mapSqlStream(sqle, msg.sstream, &sqls);
			if ( rc != OK ) {
				infErrno = STREAM_BAD_ID;
				break;
			}
		
			if ( (i = atoi(msg.data)) < 0 || i >= sqls->nresultcols ) {
				sendError("Illegal column number", msg.sstream);
			}
			else {
				sendResponse('t', strlen(sqls->colname[i]), msg.sstream, 0, sqls->colname[i]);
			}
			break;


		  case 'W':	    
			// execute command
			rc = mapSqlStream(sqle, msg.sstream, &sqls);
			if ( rc != OK ) {
				infErrno = STREAM_BAD_ID;
				break;
			}
		
			if ( sqls->hstmt ) {
				SQLFreeStmt(sqls->hstmt, SQL_CLOSE);
				SQLFreeStmt(sqls->hstmt, SQL_UNBIND);
			}
			//	Look for special extensions
			if ( strnicmp(msg.data, "commit", 6) == 0 ) {
				SQLConn	*sqlc;

				rc = mapSqlConn(sqle, sqls->connid, &sqlc);
				rc = SQLTransact(SQL_NULL_HENV, sqlc->hdbc, SQL_COMMIT);
			}
			else if ( strnicmp(msg.data, "rollback", 8) == 0 ) {
				SQLConn	*sqlc;

				rc = mapSqlConn(sqle, sqls->connid, &sqlc);
				rc = SQLTransact(SQL_NULL_HENV, sqlc->hdbc, SQL_ROLLBACK);
			}

			else if ( strnicmp(msg.data, "tables", 6) == 0 ) {
				rc = SQLTables(sqls->hstmt, NULL, 0, NULL, 0, NULL, 0, NULL, 0);
			}
			else if ( strnicmp(msg.data, "columns", 7) == 0 ) {
				UCHAR	*tbl;
				
				for ( tbl = msg.data+8; *tbl == ' ' || *tbl == '\t'; tbl++ ) { }

				rc = SQLColumns(sqls->hstmt, NULL, 0, NULL, 0, tbl, SQL_NTS, NULL, 0);
			}
			else {
				rc = SQLExecDirect(sqls->hstmt, msg.data, SQL_NTS);
			}
			outbuf[0] = '\0';
			while ( rc == SQL_NEED_DATA ) {
				PTR	pToken;
//				SDWORD	pnum;

				rc = SQLParamData(sqls->hstmt, &pToken);
//				pnum = (SDWORD) pToken;
#define pnum (int)pToken
				if ( rc == SQL_NEED_DATA ) {
					int	retcode;

					if ( sqls->setdata[pnum] == NULL || sqls->setdatalen[pnum] <= 0 ) {
						sprintf(outbuf, "Parameter %d not set\n", pnum);
						break;
					}
					for ( i = 0; i < sqls->setdatalen[pnum]; ) {
						int		togo;

						togo = 1024;
						if ( sqls->setdatalen[pnum] - i < 1024 ) {
							togo = sqls->setdatalen[pnum] - i;
						}
						retcode = SQLPutData(sqls->hstmt,
													sqls->setdata[pnum] + i, togo);
						i += togo;
						if ( retcode != SQL_SUCCESS ) {
							print_err(sqle, -1, msg.sstream, &outbuf[strlen(outbuf)], sizeof (outbuf) - strlen(outbuf));
							break;
						}
					}
					if ( retcode != SQL_SUCCESS /* && retcode != SQL_SUCCESS_WITH_INFO */) {
						break;
					}
				}
			}
			if ( rc != SQL_SUCCESS ) {
				strcat(outbuf, "Command execution failed\n");
				switch ( rc ) {
				case SQL_SUCCESS_WITH_INFO:
					strcat(outbuf, ": SQL_SUCCESS_WITH_INFO");
					print_err(sqle, -1, msg.sstream, &outbuf[strlen(outbuf)], sizeof (outbuf) - strlen(outbuf));
					break;
				case SQL_ERROR:
					strcat(outbuf, ": SQL_ERROR");
					print_err(sqle, -1, msg.sstream, &outbuf[strlen(outbuf)], sizeof (outbuf) - strlen(outbuf));
					break;
				case SQL_NEED_DATA:
					strcat(outbuf, ": SQL_NEED_DATA");
					break;
				case SQL_STILL_EXECUTING:
					strcat(outbuf, ": SQL_STILL_EXECUTING");
					break;
				case SQL_INVALID_HANDLE:
					strcat(outbuf, ": SQL_INVALID_HANDLE");
					break;
				}
				sendError(outbuf, msg.sstream);
				break;
			}
			SQLNumResultCols(sqls->hstmt, &sqls->nresultcols);
			if ( sqls->nresultcols == 0 ) {	//	was not 'select' command
				SQLRowCount(sqls->hstmt, &sqls->rowcount);	//	we don't use this, do we?
			}
			else {				//	get the column labels, save for later
				for ( i = 0; i < sqls->nresultcols; i++ ) {
					int	newlen;

					SQLDescribeCol(sqls->hstmt, (UWORD) (i+1), sqls->colname[i],
							(SWORD)sizeof(sqls->colname[i]),
							&sqls->colnamelen, &sqls->coltype[i], &sqls->collen[i],
							&sqls->scale, &sqls->nullable);
					sqls->colname[i][sqls->colnamelen] = 0;
					//	Adjust the length, since we are converting everything to strings.
					if ( (newlen = display_size(sqls->coltype[i], sqls->collen[i],
															sqls->colname[i])) != 0 ) {
						sqls->collen[i] = newlen;
					}
					if ( sqls->collen[i] == 0 ) {
						sqls->collen[i] = BUFSIZE;
					}
					sqls->data[i] = (UCHAR *) malloc(sqls->collen[i] + 1);
				/*
					SQLBindCol(sqls->hstmt, (UWORD) (i+1), newlen > 0 ? SQL_C_CHAR : SQL_C_DEFAULT,
													sqls->data[i], sqls->collen[i], &sqls->outlen[i]);
				 */
				}
				sqls->rownum = 0;
			}
			sendResponse('w', 0, msg.sstream, 0, "");
			break;


		  case 'X':
			notdone = 0;
			break;


		  default:
			sprintf(sqls->errmsg, "Unknown command: %c", msg.mtype);
			sendError(sqls->errmsg, msg.sstream);
			sqls->errmsg[0] = '\0';
			break;
		}		// end of switch (msg.mtype)
		if ( infErrno > 0 && infErrno < LAST_ERROR_NO ) {
			sendError(iError[infErrno - 1], msg.sstream);
		}
    }		// end of while (notdone)
	rc = freeSqlEnv(&sqle);

	return 0;
}

//
//	All the incoming commands should end with a newline character.
//	We read until we get one.  Then we verify that we have read as
//  many bytes as the count in message says we should.
//
int
getCommand(DBMSGP msgp, UCHAR *buf, int bufsiz)
{
	int		bytesRead = 0;
	int		rc = 0;

	msgp->mtype = '\0';
	while ( bufsiz > 0 && (rc = read(0, &buf[bytesRead], bufsiz)) > 0 ) {
		bytesRead += rc;
		bufsiz -= rc;
		msgp->bytesNotRead -= rc;
		if ( msgp->mtype == '\0' && bytesRead >= REQ_HEADER_SIZE ) {
			if ( (msgp->version = buf[1]) != '1' ) {	// wrong version, give up
				char	*wrong_version = "Message has wrong version number";
				sendResponse('h', strlen(wrong_version), 0, 0, wrong_version);
				return -1;
			}
			msgp->mtype = buf[0];
			msgp->nbytes = atoi(buf+OFFSET_LENGTH);
			msgp->sstream = atoi(buf+OFFSET_STREAM);
			msgp->data = buf+OFFSET_REQ_DATA;
			msgp->bytesNotRead = REQ_HEADER_SIZE + msgp->nbytes + 1 - bytesRead;
			if ( bufsiz > msgp->bytesNotRead ) {
				bufsiz = msgp->bytesNotRead;
			}
		}
	}
	if ( rc < 0 ) {
		//	log a problem
		//	fprintf(stderr, "Problem reading from client\n");
		return rc;
	}
	if ( msgp->bytesNotRead == 0 ) {
		msgp->data[msgp->nbytes] = 0;		// discard final newline
	}
	return bytesRead;
}


void
sendResponse(char type, int lendata, int sstream, int retcode, char *data)
{
	char	hdr[RES_HEADER_SIZE+2];

	sprintf(hdr, "%c1%11d %3d %3d ", type, lendata, sstream, retcode);
	write(1, hdr, RES_HEADER_SIZE);
	write(1, data, lendata);
	write(1, "\n", 1);
}


void
sendError(char *errmsg, int sstream)
{
	sendResponse('h', strlen(errmsg), sstream, 0, errmsg);
}


void
print_err(SQLEnv *sqle, int connid, int streamid, UCHAR * buf, int bufsiz)
{
	RETCODE		rc;
	UCHAR		stateString[40];
	SDWORD		native;
	SWORD		msglen;
	SQLConn		*sqlc;
	SQLStream	*sqls;
	HENV		*henv;
	HDBC		*hdbc;
	HSTMT		*hstmt;

	henv = sqle->henv;

	rc = mapSqlConn(sqle, connid, &sqlc);
	hdbc = rc == OK ? sqlc->hdbc : SQL_NULL_HDBC;

	rc = mapSqlStream(sqle, streamid, &sqls);
	hstmt = rc == OK ? sqls->hstmt : SQL_NULL_HSTMT;
	
	rc = SQLError(henv, hdbc, hstmt, stateString, &native, buf, (SWORD) bufsiz, &msglen);
}


#define MAX_NUM_PRECISION 15

/* Define max length of char string representation of number as:      */
/*   =  max(precision) + leading sign + E + exp sign + max exp length */
/*   =  15             + 1            + 1 + 1        + 2              */
/*   =  15 + 5                                                        */

#define MAX_NUM_STRING_SIZE (MAX_NUM_PRECISION + 5)

UDWORD
display_size(SWORD coltype, UDWORD collen, UCHAR *colname)
{
switch (coltype) {

     case SQL_CHAR:
     case SQL_VARCHAR:
          return max(collen, strlen(colname));

     case SQL_SMALLINT:
	 case SQL_TINYINT:
	 case SQL_BIT:
          return max(6, strlen(colname));

     case SQL_INTEGER:
          return max(11, strlen(colname));

	 case SQL_BIGINT:
		  return max(30, strlen(colname));

	 case SQL_DATE:
	 case SQL_TIME:
	 case SQL_TIMESTAMP:
		  return max(50, strlen(colname));

     case SQL_DECIMAL:
     case SQL_NUMERIC:
     case SQL_REAL:
     case SQL_FLOAT:
     case SQL_DOUBLE:
          return(max(MAX_NUM_STRING_SIZE, strlen(colname)));

	 case SQL_LONGVARBINARY:
	 case SQL_LONGVARCHAR:
		  return BUFSIZE;

     /* Note that this function only supports the core data types. */
	 /* For unknown data types, the caller should assume binary data */
     default:
          /* fprintf(stderr, "Unknown datatype, %d\n", coltype); */
		  return 0;
     }
}


STATUS
newSqlEnv(SQLEnv **sqle)
{
	SQLEnv	*newenv;
	STATUS	rc;

	newenv = (SQLEnv *) calloc(1, sizeof(SQLEnv));
	if (newenv == NULL) {
		return ERR;
	}

	rc = SQLAllocEnv(&newenv->henv);
	if ( rc != SQL_SUCCESS) {
		free (newenv);
		return ERR;
	}

	*sqle = newenv;
	return OK;
}


STATUS
freeSqlEnv(SQLEnv **sqle)
{
	int		i;
	STATUS	rc;

	for (i = 0; i < (*sqle)->maxstream; i++) {
		// Free this stream.
		// Connection will be freed automatically.
		rc = freeSqlStream(*sqle, i);
	}
	// dealloc the stream structures
	// dealloc the connect structures
	SQLFreeEnv((*sqle)->henv);
	// dealloc the env structure

	return OK;
}


STATUS
mapSqlConn(SQLEnv *sqle, int connid, SQLConn **sqlc)
{
	if ( connid >= 0 && connid < sqle->maxconn ) {
		*sqlc = sqle->scarray[connid];
		if ( (*sqlc)->state == SQLC_INUSE )
			return OK;
	}
	return ERR;
}


STATUS
newSqlConn(SQLEnv *sqle, char *info, int *connid)
{
	SQLConn		**newarray, *sqlc;
	int			newid = -1, i;
	STATUS		rc;

	*connid = -1;

	// Connect to the database.
	// Search for an available connection structure to reuse
	for ( i = 0; i < sqle->maxconn; i++ ) {
		sqlc = sqle->scarray[i];
		if ( sqlc != NULL && sqlc->state == SQLC_FREE ) {
			newid = i;
			break;
		}
	}
	
	if ( newid == -1 ) {
		// Assign a new connection id
		newid = sqle->maxconn++;

		// Extend the connection pointer array
		newarray = (SQLConn **) realloc((char *) sqle->scarray,
			sqle->maxconn * sizeof(SQLConn*));
		if ( newarray == NULL ) {
			return ERR;
		}
		sqle->scarray = newarray;

		// Allocate a new connection structure
		sqlc = (SQLConn *) calloc(1, sizeof(SQLConn));
		if ( sqlc == NULL ) {
			return ERR;
		}
		sqle->scarray[newid] = sqlc;
	}

	// Ask ODBC for a new connection handle
	rc = SQLAllocConnect(sqle->henv, &sqlc->hdbc);
	if (rc == SQL_ERROR) {
		return ERR;
	}

	sqlc->refcount = 0;
	sqlc->state = SQLC_INUSE;
	 
	// Extract the username, password, and database name
	rc = parseConnInfo(sqlc, info);
	if ( rc != OK ) {
		return ERR;
	}

	// Request an ODBC connection to the database
    rc = SQLConnect(sqlc->hdbc, sqlc->dbname, SQL_NTS, sqlc->user, SQL_NTS,
		sqlc->passwd, SQL_NTS);
	if ( rc != SQL_SUCCESS && rc != SQL_SUCCESS_WITH_INFO ) {
		//	log error?
		//	Should try to get something more specific from ODBC
		sprintf(sqlc->errmsg, "Connect failed: user = %s, passwd = %s, dbname = %s",
			sqlc->user, sqlc->passwd, sqlc->dbname);

		SQLDisconnect(sqlc->hdbc);
		SQLFreeConnect(sqlc->hdbc);
		return ERR;
	}
	*connid = newid;

	// Set connect option to disable auto commit
	rc = SQLSetConnectOption(sqlc->hdbc, SQL_AUTOCOMMIT, SQL_AUTOCOMMIT_OFF);
	if ( rc != SQL_SUCCESS ) {
		return WARN;
	}

	return OK;
}


STATUS
freeSqlConn(SQLEnv *sqle, int connid)
{
	SQLConn	*sqlc;
	STATUS	rc;

	rc = mapSqlConn(sqle, connid, &sqlc);
	if ( rc != OK ) {
		return WARN;
	}

	SQLDisconnect(sqlc->hdbc);
	SQLFreeConnect(sqlc->hdbc);
	sqlc->state = SQLC_FREE;
	return OK;
}


STATUS
mapSqlStream(SQLEnv *sqle, int streamid, SQLStream **sqls)
{
	if ( streamid >= 0 && streamid < sqle->maxstream ) {
		*sqls = sqle->ssarray[streamid];
		if ( (*sqls)->state == SQLS_INUSE )
			return OK;
	}
	return ERR;
}


STATUS
newSqlStream(SQLEnv *sqle, int connid, int *streamid)
{
	HSTMT		hstmt;
	SQLConn		*sqlc;
	SQLStream	**newarray, *sqls;
	int			newid = -1, i;
	STATUS		rc;

	rc = mapSqlConn(sqle, connid, &sqlc);
	if (rc != OK) {
		return ERR;
	}

	// Search for an available stream structure to reuse
	for ( i = 0; i < sqle->maxstream; i++ ) {
		sqls = sqle->ssarray[i];
		if ( sqls != NULL && sqls->state == SQLS_FREE ) {
			newid = i;
			break;
		}
	}
	
	if ( newid == -1 ) {
		// Assign a new stream id
		newid = sqle->maxstream++;

		// Extend the stream pointer array
		newarray = (SQLStream **) realloc((char *) sqle->ssarray,
			sqle->maxstream * sizeof(SQLStream*));
		if ( newarray == NULL ) {
			return ERR;
		}
		sqle->ssarray = newarray;

		// Allocate a new stream structure
		sqls = (SQLStream *) calloc(1, sizeof(SQLStream));
		if ( sqls == NULL ) {
			return ERR;
		}
		sqle->ssarray[newid] = sqls;
	}

	// Associate new stream with specified connection
	sqls->connid = connid;
	sqlc->refcount++;

	// Ask ODBC to allocate a new statement handle
	rc = SQLAllocStmt(sqlc->hdbc, &hstmt);
	if (rc == SQL_ERROR) {
		return ERR;
	}
	sqls->hstmt = hstmt;
	sqls->state = SQLS_INUSE;

	*streamid = newid;
	return OK;
}


STATUS
freeSqlStream(SQLEnv *sqle, int streamid)
{
	SQLConn		*sqlc;
	SQLStream	*sqls;
	STATUS		rc;

	rc = mapSqlStream(sqle, streamid, &sqls);
	if ( rc != OK ) {
		return WARN;
	}

	sqls->state = SQLS_FREE;

	rc = SQLFreeStmt(sqls->hstmt, SQL_DROP);

	rc = mapSqlConn(sqle, sqls->connid, &sqlc);
	if ( rc != OK ) {
		return WARN;
	}

	if ( --sqlc->refcount == 0 )
	{
		rc = freeSqlConn(sqle, sqls->connid);
		if (rc != OK) {
			return WARN;
		}
	}
	return OK;
}


STATUS
parseConnInfo(SQLConn *sqlc, char *info)
{
	UCHAR	*temp;

	// The argument 'info' points to a buffer containing a string
	// of the form "username/password/dbname\n".  We will use 'strtok'
	// to tokenize the string into the parts we need, keeping
	// copies in the 'sqlc' structure.

	temp = strtok(info, "/\n");
	if ( temp == NULL ) {
		return ERR;
	}
	strncpy(sqlc->user, temp, 48);

	temp = strtok(NULL, "/\n");
	if ( temp == NULL ) {
		return ERR;
	}
	strncpy(sqlc->passwd, temp, 48);

	temp = strtok(NULL, "/\n");
	if ( temp == NULL ) {
		return ERR;
	}
	strncpy(sqlc->dbname, temp, 48);

	return OK;
}