descriptor.c

PostgreSQL 8.1.4的源码 适用于Linux下的开源数据库系统

/* dynamic SQL support routines
 *
 * $PostgreSQL: pgsql/src/interfaces/ecpg/ecpglib/descriptor.c,v 1.12.6.2 2006/01/15 22:47:10 neilc Exp $
 */

#define POSTGRES_ECPG_INTERNAL
#include "postgres_fe.h"
#include "pg_type.h"

#include "ecpgtype.h"
#include "ecpglib.h"
#include "ecpgerrno.h"
#include "extern.h"
#include "sqlca.h"
#include "sql3types.h"

struct descriptor *all_descriptors = NULL;

/* old internal convenience function that might go away later */
static PGresult
		   *
ECPGresultByDescriptor(int line, const char *name)
{
	PGresult  **resultpp = ECPGdescriptor_lvalue(line, name);

	if (resultpp)
		return *resultpp;
	return NULL;
}

static unsigned int
ECPGDynamicType_DDT(Oid type)
{
	switch (type)
	{
		case DATEOID:
			return SQL3_DDT_DATE;
		case TIMEOID:
			return SQL3_DDT_TIME;
		case TIMESTAMPOID:
			return SQL3_DDT_TIMESTAMP;
		case TIMESTAMPTZOID:
			return SQL3_DDT_TIMESTAMP_WITH_TIME_ZONE;
		case TIMETZOID:
			return SQL3_DDT_TIME_WITH_TIME_ZONE;
		default:
			return SQL3_DDT_ILLEGAL;
	}
}

bool
ECPGget_desc_header(int lineno, const char *desc_name, int *count)
{
	PGresult   *ECPGresult;
	struct sqlca_t *sqlca = ECPGget_sqlca();

	ECPGinit_sqlca(sqlca);
	ECPGresult = ECPGresultByDescriptor(lineno, desc_name);
	if (!ECPGresult)
		return false;

	*count = PQnfields(ECPGresult);
	sqlca->sqlerrd[2] = 1;
	ECPGlog("ECPGget_desc_header: found %d attributes.\n", *count);
	return true;
}

static bool
get_int_item(int lineno, void *var, enum ECPGttype vartype, int value)
{
	switch (vartype)
	{
		case ECPGt_short:
			*(short *) var = (short) value;
			break;
		case ECPGt_int:
			*(int *) var = (int) value;
			break;
		case ECPGt_long:
			*(long *) var = (long) value;
			break;
		case ECPGt_unsigned_short:
			*(unsigned short *) var = (unsigned short) value;
			break;
		case ECPGt_unsigned_int:
			*(unsigned int *) var = (unsigned int) value;
			break;
		case ECPGt_unsigned_long:
			*(unsigned long *) var = (unsigned long) value;
			break;
#ifdef HAVE_LONG_LONG_INT_64
		case ECPGt_long_long:
			*(long long int *) var = (long long int) value;
			break;
		case ECPGt_unsigned_long_long:
			*(unsigned long long int *) var = (unsigned long long int) value;
			break;
#endif   /* HAVE_LONG_LONG_INT_64 */
		case ECPGt_float:
			*(float *) var = (float) value;
			break;
		case ECPGt_double:
			*(double *) var = (double) value;
			break;
		default:
			ECPGraise(lineno, ECPG_VAR_NOT_NUMERIC, ECPG_SQLSTATE_RESTRICTED_DATA_TYPE_ATTRIBUTE_VIOLATION, NULL);
			return (false);
	}

	return (true);
}

static bool
set_int_item(int lineno, int *target, const void *var, enum ECPGttype vartype)
{
	switch (vartype)
	{
		case ECPGt_short:
			*target = *(short *) var;
			break;
		case ECPGt_int:
			*target = *(int *) var;
			break;
		case ECPGt_long:
			*target = *(long *) var;
			break;
		case ECPGt_unsigned_short:
			*target = *(unsigned short *) var;
			break;
		case ECPGt_unsigned_int:
			*target = *(unsigned int *) var;
			break;
		case ECPGt_unsigned_long:
			*target = *(unsigned long *) var;
			break;
#ifdef HAVE_LONG_LONG_INT_64
		case ECPGt_long_long:
			*target = *(long long int *) var;
			break;
		case ECPGt_unsigned_long_long:
			*target = *(unsigned long long int *) var;
			break;
#endif   /* HAVE_LONG_LONG_INT_64 */
		case ECPGt_float:
			*target = *(float *) var;
			break;
		case ECPGt_double:
			*target = *(double *) var;
			break;
		default:
			ECPGraise(lineno, ECPG_VAR_NOT_NUMERIC, ECPG_SQLSTATE_RESTRICTED_DATA_TYPE_ATTRIBUTE_VIOLATION, NULL);
			return (false);
	}

	return true;
}

static bool
get_char_item(int lineno, void *var, enum ECPGttype vartype, char *value, int varcharsize)
{
	switch (vartype)
	{
		case ECPGt_char:
		case ECPGt_unsigned_char:
			strncpy((char *) var, value, varcharsize);
			break;
		case ECPGt_varchar:
			{
				struct ECPGgeneric_varchar *variable =
				(struct ECPGgeneric_varchar *) var;

				if (varcharsize == 0)
					strncpy(variable->arr, value, strlen(value));
				else
					strncpy(variable->arr, value, varcharsize);

				variable->len = strlen(value);
				if (varcharsize > 0 && variable->len > varcharsize)
					variable->len = varcharsize;
			}
			break;
		default:
			ECPGraise(lineno, ECPG_VAR_NOT_CHAR, ECPG_SQLSTATE_RESTRICTED_DATA_TYPE_ATTRIBUTE_VIOLATION, NULL);
			return (false);
	}

	return (true);
}

bool
ECPGget_desc(int lineno, const char *desc_name, int index,...)
{
	va_list		args;
	PGresult   *ECPGresult;
	enum ECPGdtype type;
	int			ntuples,
				act_tuple;
	struct variable data_var;
	struct sqlca_t *sqlca = ECPGget_sqlca();

	va_start(args, index);
	ECPGinit_sqlca(sqlca);
	ECPGresult = ECPGresultByDescriptor(lineno, desc_name);
	if (!ECPGresult)
		return (false);

	ntuples = PQntuples(ECPGresult);
	if (ntuples < 1)
	{
		ECPGraise(lineno, ECPG_NOT_FOUND, ECPG_SQLSTATE_NO_DATA, NULL);
		return (false);
	}

	if (index < 1 || index > PQnfields(ECPGresult))
	{
		ECPGraise(lineno, ECPG_INVALID_DESCRIPTOR_INDEX, ECPG_SQLSTATE_INVALID_DESCRIPTOR_INDEX, NULL);
		return (false);
	}

	ECPGlog("ECPGget_desc: reading items for tuple %d\n", index);
	--index;

	type = va_arg(args, enum ECPGdtype);

	memset(&data_var, 0, sizeof data_var);
	data_var.type = ECPGt_EORT;
	data_var.ind_type = ECPGt_NO_INDICATOR;

	while (type != ECPGd_EODT)
	{
		char		type_str[20];
		long		varcharsize;
		long		offset;
		long		arrsize;
		enum ECPGttype vartype;
		void	   *var;

		vartype = va_arg(args, enum ECPGttype);
		var = va_arg(args, void *);
		varcharsize = va_arg(args, long);
		arrsize = va_arg(args, long);
		offset = va_arg(args, long);

		switch (type)
		{
			case (ECPGd_indicator):
				data_var.ind_type = vartype;
				data_var.ind_pointer = var;
				data_var.ind_varcharsize = varcharsize;
				data_var.ind_arrsize = arrsize;
				data_var.ind_offset = offset;
				if (data_var.ind_arrsize == 0 || data_var.ind_varcharsize == 0)
					data_var.ind_value = *((void **) (data_var.ind_pointer));
				else
					data_var.ind_value = data_var.ind_pointer;
				break;

			case ECPGd_data:
				data_var.type = vartype;
				data_var.pointer = var;
				data_var.varcharsize = varcharsize;
				data_var.arrsize = arrsize;
				data_var.offset = offset;
				if (data_var.arrsize == 0 || data_var.varcharsize == 0)
					data_var.value = *((void **) (data_var.pointer));
				else
					data_var.value = data_var.pointer;
				break;

			case ECPGd_name:
				if (!get_char_item(lineno, var, vartype, PQfname(ECPGresult, index), varcharsize))
					return (false);

				ECPGlog("ECPGget_desc: NAME = %s\n", PQfname(ECPGresult, index));
				break;

			case ECPGd_nullable:
				if (!get_int_item(lineno, var, vartype, 1))
					return (false);

				break;

			case ECPGd_key_member:
				if (!get_int_item(lineno, var, vartype, 0))
					return (false);

				break;

			case ECPGd_scale:
				if (!get_int_item(lineno, var, vartype, (PQfmod(ECPGresult, index) - VARHDRSZ) & 0xffff))
					return (false);

				ECPGlog("ECPGget_desc: SCALE = %d\n", (PQfmod(ECPGresult, index) - VARHDRSZ) & 0xffff);
				break;

			case ECPGd_precision:
				if (!get_int_item(lineno, var, vartype, PQfmod(ECPGresult, index) >> 16))
					return (false);

				ECPGlog("ECPGget_desc: PRECISION = %d\n", PQfmod(ECPGresult, index) >> 16);
				break;

			case ECPGd_octet:
				if (!get_int_item(lineno, var, vartype, PQfsize(ECPGresult, index)))
					return (false);

				ECPGlog("ECPGget_desc: OCTET_LENGTH = %d\n", PQfsize(ECPGresult, index));
				break;

			case ECPGd_length:
				if (!get_int_item(lineno, var, vartype, PQfmod(ECPGresult, index) - VARHDRSZ))
					return (false);

				ECPGlog("ECPGget_desc: LENGTH = %d\n", PQfmod(ECPGresult, index) - VARHDRSZ);
				break;

			case ECPGd_type:
				if (!get_int_item(lineno, var, vartype, ECPGDynamicType(PQftype(ECPGresult, index))))
					return (false);

				ECPGlog("ECPGget_desc: TYPE = %d\n", ECPGDynamicType(PQftype(ECPGresult, index)));
				break;