convert.c

关系型数据库 Postgresql 6.5.2

				my_strcpy(&new_statement[npos], sizeof(stmt->stmt_with_params) - npos, buf, used);
				npos += strlen(&new_statement[npos]);
			}
			else {
				strcpy(&new_statement[npos], param_string);
				npos += strlen(param_string);
			}

			if (param_sqltype == SQL_BIT)
				new_statement[npos++] = '\'';	/*    Close Quote */

			break;

		}

	}	/* end, for */

	// make sure new_statement is always null-terminated
	new_statement[npos] = '\0';


	if(stmt->hdbc->DriverToDataSource != NULL) {
		int length = strlen (new_statement);
		stmt->hdbc->DriverToDataSource (stmt->hdbc->translation_option,
										SQL_CHAR,
										new_statement, length,
										new_statement, length, NULL,
										NULL, 0, NULL);
	}


	return SQL_SUCCESS;
}

char *
mapFunction(char *func)
{
int i;

	for (i = 0; mapFuncs[i][0]; i++)
		if ( ! stricmp(mapFuncs[i][0], func))
			return mapFuncs[i][1];

	return NULL;
}

//	This function returns a pointer to static memory!
char *
convert_escape(char *value)
{
char key[32], val[256];
static char escape[1024];
char func[32], the_rest[1024];
char *mapFunc;

	sscanf(value, "%s %[^\r]", key, val);

	mylog("convert_escape: key='%s', val='%s'\n", key, val);

	if ( ! strcmp(key, "d") ||
		 ! strcmp(key, "t") ||
		 ! strcmp(key, "ts")) {

		strcpy(escape, val);
	}
	else if ( ! strcmp(key, "fn")) {
		sscanf(val, "%[^(]%[^\r]", func, the_rest);
		mapFunc = mapFunction(func);
		if ( ! mapFunc)
			return NULL;
		else {
			strcpy(escape, mapFunc);
			strcat(escape, the_rest);
		}

	}
	else {
		return NULL;
	}

	return escape;

}


char *
convert_money(char *s)
{
size_t i = 0, out = 0;

	for (i = 0; i < strlen(s); i++) {
		if (s[i] == '$' || s[i] == ',' || s[i] == ')')
			; // skip these characters
		else if (s[i] == '(')
			s[out++] = '-';
		else
			s[out++] = s[i];
	}
	s[out] = '\0';
	return s;
}



/*	This function parses a character string for date/time info and fills in SIMPLE_TIME */
/*	It does not zero out SIMPLE_TIME in case it is desired to initialize it with a value */
char
parse_datetime(char *buf, SIMPLE_TIME *st)
{
int y,m,d,hh,mm,ss;
int nf;
	
	y = m = d = hh = mm = ss = 0;

	if (buf[4] == '-')	/* year first */
		nf = sscanf(buf, "%4d-%2d-%2d %2d:%2d:%2d", &y,&m,&d,&hh,&mm,&ss);
	else
		nf = sscanf(buf, "%2d-%2d-%4d %2d:%2d:%2d", &m,&d,&y,&hh,&mm,&ss);

	if (nf == 5 || nf == 6) {
		st->y = y;
		st->m = m;
		st->d = d;
		st->hh = hh;
		st->mm = mm;
		st->ss = ss;

		return TRUE;
	}

	if (buf[4] == '-')	/* year first */
		nf = sscanf(buf, "%4d-%2d-%2d", &y, &m, &d);
	else
		nf = sscanf(buf, "%2d-%2d-%4d", &m, &d, &y);

	if (nf == 3) {
		st->y = y;
		st->m = m;
		st->d = d;

		return TRUE;
	}

	nf = sscanf(buf, "%2d:%2d:%2d", &hh, &mm, &ss);
	if (nf == 2 || nf == 3) {
		st->hh = hh;
		st->mm = mm;
		st->ss = ss;

		return TRUE;
	}

	return FALSE;
}

/*	Change linefeed to carriage-return/linefeed */
int
convert_linefeeds(char *si, char *dst, size_t max)
{
size_t i = 0, out = 0;

	for (i = 0; i < strlen(si) && out < max - 1; i++) {
		if (si[i] == '\n') {
			/*	Only add the carriage-return if needed */
			if (i > 0 && si[i-1] == '\r') {
				dst[out++] = si[i];
				continue;
			}

			dst[out++] = '\r';
			dst[out++] = '\n';
		}
		else
			dst[out++] = si[i];
	}
	dst[out] = '\0';
	return out;
}

/*	Change carriage-return/linefeed to just linefeed 
	Plus, escape any special characters.
*/
char *
convert_special_chars(char *si, char *dst, int used)
{
size_t i = 0, out = 0, max;
static char sout[TEXT_FIELD_SIZE+5];
char *p;

	if (dst)
		p = dst;
	else
		p = sout;

	p[0] = '\0';

	if (used == SQL_NTS)
		max = strlen(si);
	else
		max = used;

	for (i = 0; i < max; i++) {
		if (si[i] == '\r' && i+1 < strlen(si) && si[i+1] == '\n') 
			continue;
		else if (si[i] == '\'' || si[i] == '\\')
			p[out++] = '\\';

		p[out++] = si[i];
	}
	p[out] = '\0';
	return p;
}

/*	!!! Need to implement this function !!!  */
int
convert_pgbinary_to_char(char *value, char *rgbValue, int cbValueMax)
{
	mylog("convert_pgbinary_to_char: value = '%s'\n", value);

	strncpy_null(rgbValue, value, cbValueMax);
	return 0;
}

unsigned int
conv_from_octal(unsigned char *s)
{
int i, y=0;

	for (i = 1; i <= 3; i++) {
		y += (s[i] - 48) * (int) pow(8, 3-i);
	}

	return y;

}

unsigned int
conv_from_hex(unsigned char *s)
{
int i, y=0, val;

	for (i = 1; i <= 2; i++) {

        if (s[i] >= 'a' && s[i] <= 'f')
            val = s[i] - 'a' + 10;
        else if (s[i] >= 'A' && s[i] <= 'F')
            val = s[i] - 'A' + 10;
        else
            val = s[i] - '0';

		y += val * (int) pow(16, 2-i);
	}

	return y;
}

//	convert octal escapes to bytes
int
convert_from_pgbinary(unsigned char *value, unsigned char *rgbValue, int cbValueMax)
{
size_t i;
int o=0;

	
	for (i = 0; i < strlen(value); ) {
		if (value[i] == '\\') {
			rgbValue[o] = conv_from_octal(&value[i]);
			i += 4;
		}
		else {
			rgbValue[o] = value[i++];
		}
		mylog("convert_from_pgbinary: i=%d, rgbValue[%d] = %d, %c\n", i, o, rgbValue[o], rgbValue[o]);
		o++;
	}

	rgbValue[o] = '\0';	// extra protection

	return o;
}


char *
conv_to_octal(unsigned char val)
{
int i;
static char x[6];

	x[0] = '\\';
	x[1] = '\\';
	x[5] = '\0';

	for (i = 4; i > 1; i--) {
		x[i] = (val & 7) + 48;
		val >>= 3;
	}

	return x;
}

//	convert non-ascii bytes to octal escape sequences
int
convert_to_pgbinary(unsigned char *in, char *out, int len)
{
int i, o=0;


	for (i = 0; i < len; i++) {
		mylog("convert_to_pgbinary: in[%d] = %d, %c\n", i, in[i], in[i]);
		if ( isalnum(in[i]) || in[i] == ' ') {
			out[o++] = in[i];
		}
		else {
			strcpy(&out[o], conv_to_octal(in[i])); 
			o += 5;
		}

	}

	mylog("convert_to_pgbinary: returning %d, out='%.*s'\n", o, o, out);

	return o;
}


void
encode(char *in, char *out)
{
unsigned int i, o = 0;

	for (i = 0; i < strlen(in); i++) {
		if ( in[i] == '+') {
			sprintf(&out[o], "%%2B");
			o += 3;
		}
		else if ( isspace(in[i])) {
			out[o++] = '+';
		}
		else if ( ! isalnum(in[i])) {
			sprintf(&out[o], "%%%02x", in[i]);
			o += 3;
		}
		else
			out[o++] = in[i];
	}
	out[o++] = '\0';
}


void
decode(char *in, char *out)
{
unsigned int i, o = 0;

	for (i = 0; i < strlen(in); i++) { 
		if (in[i] == '+')
			out[o++] = ' ';
		else if (in[i] == '%') {
			sprintf(&out[o++], "%c", conv_from_hex(&in[i]));
			i+=2;
		}
		else
			out[o++] = in[i];
	}
	out[o++] = '\0';
}



/*	1. get oid (from 'value')
	2. open the large object
	3. read from the large object (handle multiple GetData)
	4. close when read less than requested?  -OR-
		lseek/read each time
		handle case where application receives truncated and
		decides not to continue reading.

	CURRENTLY, ONLY LONGVARBINARY is handled, since that is the only
	data type currently mapped to a PG_TYPE_LO.  But, if any other types
	are desired to map to a large object (PG_TYPE_LO), then that would 
	need to be handled here.  For example, LONGVARCHAR could possibly be
	mapped to PG_TYPE_LO someday, instead of PG_TYPE_TEXT as it is now.
*/
int
convert_lo(StatementClass *stmt, void *value, Int2 fCType, PTR rgbValue, 
		   SDWORD cbValueMax, SDWORD *pcbValue)
{
Oid oid;
int retval, result, left = -1;
int bind_row = stmt->bind_row;
BindInfoClass *bindInfo = NULL;


/*	If using SQLGetData, then current_col will be set */
	if (stmt->current_col >= 0) {
		bindInfo = &stmt->bindings[stmt->current_col];
		left = bindInfo->data_left;
	}

	/*	if this is the first call for this column,
		open the large object for reading 
	*/

	if ( ! bindInfo || bindInfo->data_left == -1) {
		oid = atoi(value);
		stmt->lobj_fd = lo_open(stmt->hdbc, oid, INV_READ);
		if (stmt->lobj_fd < 0) {
			stmt->errornumber = STMT_EXEC_ERROR;
			stmt->errormsg = "Couldnt open large object for reading.";
			return COPY_GENERAL_ERROR;
		}

		/*	Get the size */
		retval = lo_lseek(stmt->hdbc, stmt->lobj_fd, 0L, SEEK_END);
		if (retval >= 0) {

			left = lo_tell(stmt->hdbc, stmt->lobj_fd);
			if (bindInfo)
				bindInfo->data_left = left;

			/*	return to beginning */
			lo_lseek(stmt->hdbc, stmt->lobj_fd, 0L, SEEK_SET);
		}
	}

	if (left == 0) {
		return COPY_NO_DATA_FOUND;
	}

	if (stmt->lobj_fd < 0) {
		stmt->errornumber = STMT_EXEC_ERROR;
		stmt->errormsg = "Large object FD undefined for multiple read.";
		return COPY_GENERAL_ERROR;
	}

	retval = lo_read(stmt->hdbc, stmt->lobj_fd, (char *) rgbValue, cbValueMax);
	if (retval < 0) {
		lo_close(stmt->hdbc, stmt->lobj_fd);
		stmt->lobj_fd = -1;

		stmt->errornumber = STMT_EXEC_ERROR;
		stmt->errormsg = "Error reading from large object.";
		return COPY_GENERAL_ERROR;
	}

	if (retval < left)
		result = COPY_RESULT_TRUNCATED;
	else
		result = COPY_OK;

	if (pcbValue)
		*pcbValue = left < 0 ? SQL_NO_TOTAL : left;


	if (bindInfo && bindInfo->data_left > 0) 
		bindInfo->data_left -= retval;


	if (! bindInfo || bindInfo->data_left == 0) {
		lo_close(stmt->hdbc, stmt->lobj_fd);
		stmt->lobj_fd = -1;	/* prevent further reading */
	}


	return result;

}