execute.c

PostgreSQL 8.1.4的源码 适用于Linux下的开源数据库系统

/* $PostgreSQL: pgsql/src/interfaces/ecpg/ecpglib/execute.c,v 1.43.2.2 2006/04/24 09:45:44 meskes Exp $ */

/*
 * The aim is to get a simpler inteface to the database routines.
 * All the tidieous messing around with tuples is supposed to be hidden
 * by this function.
 */
/* Author: Linus Tolke
   (actually most if the code is "borrowed" from the distribution and just
   slightly modified)
 */

/* Taken over as part of PostgreSQL by Michael Meskes <[e-mail]>
   on Feb. 5th, 1998 */

#define POSTGRES_ECPG_INTERNAL
#include "postgres_fe.h"

#include <stdio.h>
#include <locale.h>

#include "pg_type.h"

#include "ecpgtype.h"
#include "ecpglib.h"
#include "ecpgerrno.h"
#include "extern.h"
#include "sqlca.h"
#include "sql3types.h"
#include "pgtypes_numeric.h"
#include "pgtypes_date.h"
#include "pgtypes_timestamp.h"
#include "pgtypes_interval.h"

/* This function returns a newly malloced string that has the  \
   in the argument quoted with \ and the ' quoted with ' as SQL92 says.
 */
static char *
quote_postgres(char *arg, int lineno)
{
	char	   *res = (char *) ECPGalloc(2 * strlen(arg) + 3, lineno);
	int			i,
				ri = 0;

	if (!res)
		return (res);

	if (strchr(arg, '\\') != NULL)
		res[ri++] = ESCAPE_STRING_SYNTAX;
	res[ri++] = '\'';

	for (i = 0; arg[i]; i++, ri++)
	{
		if (SQL_STR_DOUBLE(arg[i]))
			res[ri++] = arg[i];
		res[ri] = arg[i];
	}

	res[ri++] = '\'';
	res[ri] = '\0';

	ECPGfree(arg);
	return res;
}

#if defined(__GNUC__) && (defined (__powerpc__) || defined(__amd64__) || defined(__x86_64__))
#define APREF ap
#else
#define APREF *ap
#endif

void
ECPGget_variable(va_list APREF, enum ECPGttype type, struct variable * var, bool indicator)
{
	var->type = type;
	var->pointer = va_arg(APREF, char *);

	var->varcharsize = va_arg(APREF, long);
	var->arrsize = va_arg(APREF, long);
	var->offset = va_arg(APREF, long);

	if (var->arrsize == 0 || var->varcharsize == 0)
		var->value = *((char **) (var->pointer));
	else
		var->value = var->pointer;

	/*
	 * negative values are used to indicate an array without given bounds
	 */
	/* reset to zero for us */
	if (var->arrsize < 0)
		var->arrsize = 0;
	if (var->varcharsize < 0)
		var->varcharsize = 0;

	var->next = NULL;

	if (indicator)
	{
		var->ind_type = va_arg(APREF, enum ECPGttype);
		var->ind_pointer = va_arg(APREF, char *);
		var->ind_varcharsize = va_arg(APREF, long);
		var->ind_arrsize = va_arg(APREF, long);
		var->ind_offset = va_arg(APREF, long);

		if (var->ind_type != ECPGt_NO_INDICATOR
			&& (var->ind_arrsize == 0 || var->ind_varcharsize == 0))
			var->ind_value = *((char **) (var->ind_pointer));
		else
			var->ind_value = var->ind_pointer;

		/*
		 * negative values are used to indicate an array without given bounds
		 */
		/* reset to zero for us */
		if (var->ind_arrsize < 0)
			var->ind_arrsize = 0;
		if (var->ind_varcharsize < 0)
			var->ind_varcharsize = 0;
	}
}

#undef APREF

/*
 * create a list of variables
 * The variables are listed with input variables preceding outputvariables
 * The end of each group is marked by an end marker.
 * per variable we list:
 * type - as defined in ecpgtype.h
 * value - where to store the data
 * varcharsize - length of string in case we have a stringvariable, else 0
 * arraysize - 0 for pointer (we don't know the size of the array),
 * 1 for simple variable, size for arrays
 * offset - offset between ith and (i+1)th entry in an array,
 * normally that means sizeof(type)
 * ind_type - type of indicator variable
 * ind_value - pointer to indicator variable
 * ind_varcharsize - empty
 * ind_arraysize -	arraysize of indicator array
 * ind_offset - indicator offset
 */
static bool
create_statement(int lineno, int compat, int force_indicator, struct connection * connection, struct statement ** stmt, const char *query, va_list ap)
{
	struct variable **list = &((*stmt)->inlist);
	enum ECPGttype type;

	if (!(*stmt = (struct statement *) ECPGalloc(sizeof(struct statement), lineno)))
		return false;

	(*stmt)->command = ECPGstrdup(query, lineno);
	(*stmt)->connection = connection;
	(*stmt)->lineno = lineno;
	(*stmt)->compat = compat;
	(*stmt)->force_indicator = force_indicator;

	list = &((*stmt)->inlist);

	type = va_arg(ap, enum ECPGttype);

	while (type != ECPGt_EORT)
	{
		if (type == ECPGt_EOIT)
			list = &((*stmt)->outlist);
		else
		{
			struct variable *var,
					   *ptr;

			if (!(var = (struct variable *) ECPGalloc(sizeof(struct variable), lineno)))
				return false;

#if defined(__GNUC__) && (defined (__powerpc__) || defined(__amd64__) || defined(__x86_64__))
			ECPGget_variable(ap, type, var, true);
#else
			ECPGget_variable(&ap, type, var, true);
#endif

			/* if variable is NULL, the statement hasn't been prepared */
			if (var->pointer == NULL)
			{
				ECPGraise(lineno, ECPG_INVALID_STMT, ECPG_SQLSTATE_INVALID_SQL_STATEMENT_NAME, NULL);
				ECPGfree(var);
				return false;
			}

			for (ptr = *list; ptr && ptr->next; ptr = ptr->next);

			if (ptr == NULL)
				*list = var;
			else
				ptr->next = var;
		}

		type = va_arg(ap, enum ECPGttype);
	}

	return (true);
}

static void
free_variable(struct variable * var)
{
	struct variable *var_next;

	if (var == NULL)
		return;
	var_next = var->next;
	ECPGfree(var);

	while (var_next)
	{
		var = var_next;
		var_next = var->next;
		ECPGfree(var);
	}
}

static void
free_statement(struct statement * stmt)
{
	if (stmt == NULL)
		return;
	free_variable(stmt->inlist);
	free_variable(stmt->outlist);
	ECPGfree(stmt->command);
	ECPGfree(stmt);
}

static char *
next_insert(char *text)
{
	char	   *ptr = text;
	bool		string = false;

	for (; *ptr != '\0' && (*ptr != '?' || string); ptr++)
	{
		if (*ptr == '\\')		/* escape character */
			ptr++;
		else if (*ptr == '\'')
			string = string ? false : true;
	}

	return (*ptr == '\0') ? NULL : ptr;
}

static void
ECPGtypeinfocache_push(struct ECPGtype_information_cache ** cache, int oid, bool isarray, int lineno)
{
	struct ECPGtype_information_cache *new_entry
	= (struct ECPGtype_information_cache *) ECPGalloc(sizeof(struct ECPGtype_information_cache), lineno);

	new_entry->oid = oid;
	new_entry->isarray = isarray;
	new_entry->next = *cache;
	*cache = new_entry;
}

static enum ARRAY_TYPE
ECPGis_type_an_array(int type, const struct statement * stmt, const struct variable * var)
{
	char	   *array_query;
	enum ARRAY_TYPE isarray = ECPG_ARRAY_NOT_SET;
	PGresult   *query;
	struct ECPGtype_information_cache *cache_entry;

	if ((stmt->connection->cache_head) == NULL)
	{
		/*
		 * Text like types are not an array for ecpg, but postgres counts them
		 * as an array. This define reminds you to not 'correct' these values.
		 */
#define not_an_array_in_ecpg ECPG_ARRAY_NONE

		/* populate cache with well known types to speed things up */
		ECPGtypeinfocache_push(&(stmt->connection->cache_head), BOOLOID, ECPG_ARRAY_NONE, stmt->lineno);
		ECPGtypeinfocache_push(&(stmt->connection->cache_head), BYTEAOID, ECPG_ARRAY_NONE, stmt->lineno);
		ECPGtypeinfocache_push(&(stmt->connection->cache_head), CHAROID, ECPG_ARRAY_NONE, stmt->lineno);
		ECPGtypeinfocache_push(&(stmt->connection->cache_head), NAMEOID, not_an_array_in_ecpg, stmt->lineno);
		ECPGtypeinfocache_push(&(stmt->connection->cache_head), INT8OID, ECPG_ARRAY_NONE, stmt->lineno);
		ECPGtypeinfocache_push(&(stmt->connection->cache_head), INT2OID, ECPG_ARRAY_NONE, stmt->lineno);
		ECPGtypeinfocache_push(&(stmt->connection->cache_head), INT2VECTOROID, ECPG_ARRAY_VECTOR, stmt->lineno);
		ECPGtypeinfocache_push(&(stmt->connection->cache_head), INT4OID, ECPG_ARRAY_NONE, stmt->lineno);
		ECPGtypeinfocache_push(&(stmt->connection->cache_head), REGPROCOID, ECPG_ARRAY_NONE, stmt->lineno);
		ECPGtypeinfocache_push(&(stmt->connection->cache_head), TEXTOID, ECPG_ARRAY_NONE, stmt->lineno);
		ECPGtypeinfocache_push(&(stmt->connection->cache_head), OIDOID, ECPG_ARRAY_NONE, stmt->lineno);
		ECPGtypeinfocache_push(&(stmt->connection->cache_head), TIDOID, ECPG_ARRAY_NONE, stmt->lineno);
		ECPGtypeinfocache_push(&(stmt->connection->cache_head), XIDOID, ECPG_ARRAY_NONE, stmt->lineno);
		ECPGtypeinfocache_push(&(stmt->connection->cache_head), CIDOID, ECPG_ARRAY_NONE, stmt->lineno);
		ECPGtypeinfocache_push(&(stmt->connection->cache_head), OIDVECTOROID, ECPG_ARRAY_VECTOR, stmt->lineno);
		ECPGtypeinfocache_push(&(stmt->connection->cache_head), POINTOID, ECPG_ARRAY_VECTOR, stmt->lineno);
		ECPGtypeinfocache_push(&(stmt->connection->cache_head), LSEGOID, ECPG_ARRAY_VECTOR, stmt->lineno);
		ECPGtypeinfocache_push(&(stmt->connection->cache_head), PATHOID, ECPG_ARRAY_NONE, stmt->lineno);
		ECPGtypeinfocache_push(&(stmt->connection->cache_head), BOXOID, ECPG_ARRAY_VECTOR, stmt->lineno);
		ECPGtypeinfocache_push(&(stmt->connection->cache_head), POLYGONOID, ECPG_ARRAY_NONE, stmt->lineno);
		ECPGtypeinfocache_push(&(stmt->connection->cache_head), LINEOID, ECPG_ARRAY_VECTOR, stmt->lineno);
		ECPGtypeinfocache_push(&(stmt->connection->cache_head), FLOAT4OID, ECPG_ARRAY_NONE, stmt->lineno);
		ECPGtypeinfocache_push(&(stmt->connection->cache_head), FLOAT8OID, ECPG_ARRAY_NONE, stmt->lineno);
		ECPGtypeinfocache_push(&(stmt->connection->cache_head), ABSTIMEOID, ECPG_ARRAY_NONE, stmt->lineno);
		ECPGtypeinfocache_push(&(stmt->connection->cache_head), RELTIMEOID, ECPG_ARRAY_NONE, stmt->lineno);
		ECPGtypeinfocache_push(&(stmt->connection->cache_head), TINTERVALOID, ECPG_ARRAY_NONE, stmt->lineno);
		ECPGtypeinfocache_push(&(stmt->connection->cache_head), UNKNOWNOID, ECPG_ARRAY_NONE, stmt->lineno);
		ECPGtypeinfocache_push(&(stmt->connection->cache_head), CIRCLEOID, ECPG_ARRAY_NONE, stmt->lineno);
		ECPGtypeinfocache_push(&(stmt->connection->cache_head), CASHOID, ECPG_ARRAY_NONE, stmt->lineno);
		ECPGtypeinfocache_push(&(stmt->connection->cache_head), INETOID, ECPG_ARRAY_NONE, stmt->lineno);
		ECPGtypeinfocache_push(&(stmt->connection->cache_head), CIDROID, ECPG_ARRAY_NONE, stmt->lineno);
		ECPGtypeinfocache_push(&(stmt->connection->cache_head), BPCHAROID, ECPG_ARRAY_NONE, stmt->lineno);
		ECPGtypeinfocache_push(&(stmt->connection->cache_head), VARCHAROID, ECPG_ARRAY_NONE, stmt->lineno);
		ECPGtypeinfocache_push(&(stmt->connection->cache_head), DATEOID, ECPG_ARRAY_NONE, stmt->lineno);
		ECPGtypeinfocache_push(&(stmt->connection->cache_head), TIMEOID, ECPG_ARRAY_NONE, stmt->lineno);
		ECPGtypeinfocache_push(&(stmt->connection->cache_head), TIMESTAMPOID, ECPG_ARRAY_NONE, stmt->lineno);
		ECPGtypeinfocache_push(&(stmt->connection->cache_head), TIMESTAMPTZOID, ECPG_ARRAY_NONE, stmt->lineno);
		ECPGtypeinfocache_push(&(stmt->connection->cache_head), INTERVALOID, ECPG_ARRAY_NONE, stmt->lineno);
		ECPGtypeinfocache_push(&(stmt->connection->cache_head), TIMETZOID, ECPG_ARRAY_NONE, stmt->lineno);
		ECPGtypeinfocache_push(&(stmt->connection->cache_head), ZPBITOID, ECPG_ARRAY_NONE, stmt->lineno);
		ECPGtypeinfocache_push(&(stmt->connection->cache_head), VARBITOID, ECPG_ARRAY_NONE, stmt->lineno);
		ECPGtypeinfocache_push(&(stmt->connection->cache_head), NUMERICOID, ECPG_ARRAY_NONE, stmt->lineno);
	}

	for (cache_entry = (stmt->connection->cache_head); cache_entry != NULL; cache_entry = cache_entry->next)
	{
		if (cache_entry->oid == type)
			return cache_entry->isarray;
	}

	array_query = (char *) ECPGalloc(strlen("select typlen from pg_type where oid= and typelem<>0") + 11, stmt->lineno);
	sprintf(array_query, "select typlen from pg_type where oid=%d and typelem<>0", type);
	query = PQexec(stmt->connection->connection, array_query);
	ECPGfree(array_query);
	if (PQresultStatus(query) == PGRES_TUPLES_OK)
	{
		if (PQntuples(query) == 0)
			isarray = ECPG_ARRAY_NONE;
		else
		{
			isarray = (atol((char *) PQgetvalue(query, 0, 0)) == -1) ? ECPG_ARRAY_ARRAY : ECPG_ARRAY_VECTOR;
			if (ECPGDynamicType(type) == SQL3_CHARACTER ||
				ECPGDynamicType(type) == SQL3_CHARACTER_VARYING)
			{
				/*
				 * arrays of character strings are not yet implemented
				 */
				isarray = ECPG_ARRAY_NONE;
			}
		}
	}
	PQclear(query);
	ECPGtypeinfocache_push(&(stmt->connection->cache_head), type, isarray, stmt->lineno);
	ECPGlog("ECPGis_type_an_array line %d: TYPE database: %d C: %d array: %s\n", stmt->lineno, type, var->type, isarray ? "Yes" : "No");
	return isarray;
}


bool
ECPGstore_result(const PGresult *results, int act_field,
				 const struct statement * stmt, struct variable * var)
{
	enum ARRAY_TYPE isarray;
	int			act_tuple,
				ntuples = PQntuples(results);
	bool		status = true;

	isarray = ECPGis_type_an_array(PQftype(results, act_field), stmt, var);

	if (isarray == ECPG_ARRAY_NONE)
	{
		/*
		 * if we don't have enough space, we cannot read all tuples
		 */
		if ((var->arrsize > 0 && ntuples > var->arrsize) || (var->ind_arrsize > 0 && ntuples > var->ind_arrsize))
		{
			ECPGlog("ECPGstore_result line %d: Incorrect number of matches: %d don't fit into array of %d\n",
					stmt->lineno, ntuples, var->arrsize);
			ECPGraise(stmt->lineno, INFORMIX_MODE(stmt->compat) ? ECPG_INFORMIX_SUBSELECT_NOT_ONE : ECPG_TOO_MANY_MATCHES, ECPG_SQLSTATE_CARDINALITY_VIOLATION, NULL);
			return false;
		}
	}
	else
	{
		/*
		 * since we read an array, the variable has to be an array too
		 */
		if (var->arrsize == 0)
		{
			ECPGraise(stmt->lineno, ECPG_NO_ARRAY, ECPG_SQLSTATE_DATATYPE_MISMATCH, NULL);
			return false;
		}
	}

	/*
	 * allocate memory for NULL pointers
	 */
	if ((var->arrsize == 0 || var->varcharsize == 0) && var->value == NULL)
	{
		int			len = 0;

		switch (var->type)
		{
			case ECPGt_char:
			case ECPGt_unsigned_char:
				if (!var->varcharsize && !var->arrsize)
				{
					/* special mode for handling char**foo=0 */
					for (act_tuple = 0; act_tuple < ntuples; act_tuple++)
						len += strlen(PQgetvalue(results, act_tuple, act_field)) + 1;
					len *= var->offset; /* should be 1, but YMNK */
					len += (ntuples + 1) * sizeof(char *);

					ECPGlog("ECPGstore_result: line %d: allocating %d bytes for %d tuples (char**=0)",
							stmt->lineno, len, ntuples);
				}
				else
				{
					var->varcharsize = 0;
					/* check strlen for each tuple */
					for (act_tuple = 0; act_tuple < ntuples; act_tuple++)
					{
						int			len = strlen(PQgetvalue(results, act_tuple, act_field)) + 1;

						if (len > var->varcharsize)
							var->varcharsize = len;
					}
					var->offset *= var->varcharsize;
					len = var->offset * ntuples;
				}
				break;
			case ECPGt_varchar:
				len = ntuples * (var->varcharsize + sizeof(int));
				break;
			default:
				len = var->offset * ntuples;
				break;
		}
		var->value = (char *) ECPGalloc(len, stmt->lineno);
		*((char **) var->pointer) = var->value;
		ECPGadd_mem(var->value, stmt->lineno);
	}

	/* allocate indicator variable if needed */
	if ((var->ind_arrsize == 0 || var->ind_varcharsize == 0) && var->ind_value == NULL && var->ind_pointer != NULL)
	{
		int			len = var->ind_offset * ntuples;

		var->ind_value = (char *) ECPGalloc(len, stmt->lineno);
		*((char **) var->ind_pointer) = var->ind_value;
		ECPGadd_mem(var->ind_value, stmt->lineno);
	}

	/* fill the variable with the tuple(s) */
	if (!var->varcharsize && !var->arrsize &&
		(var->type == ECPGt_char || var->type == ECPGt_unsigned_char))
	{
		/* special mode for handling char**foo=0 */

		/* filling the array of (char*)s */
		char	  **current_string = (char **) var->value;

		/* storing the data (after the last array element) */
		char	   *current_data_location = (char *) &current_string[ntuples + 1];

		for (act_tuple = 0; act_tuple < ntuples && status; act_tuple++)
		{
			int			len = strlen(PQgetvalue(results, act_tuple, act_field)) + 1;

			if (!ECPGget_data(results, act_tuple, act_field, stmt->lineno,
							  var->type, var->ind_type, current_data_location,
							  var->ind_value, len, 0, var->ind_offset, isarray, stmt->compat, stmt->force_indicator))
				status = false;
			else
			{
				*current_string = current_data_location;
				current_data_location += len;
				current_string++;
			}