execute.c

postgresql8.3.4源码,开源数据库

/* $PostgreSQL: pgsql/src/interfaces/ecpg/ecpglib/execute.c,v 1.76.2.1 2008/03/01 03:26:44 tgl 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 <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 ' and \
 *	escaped.
 */
static char *
quote_postgres(char *arg, bool quote, int lineno)
{
	char	   *res;
	size_t		length;
	size_t		escaped_len;
	size_t		buffer_len;

	/*
	 * if quote is false we just need to store things in a descriptor they
	 * will be quoted once they are inserted in a statement
	 */
	if (!quote)
		return arg;
	else
	{
		length = strlen(arg);
		buffer_len = 2 * length + 1;
		res = (char *) ecpg_alloc(buffer_len + 3, lineno);
		if (!res)
			return (res);
		escaped_len = PQescapeString(res + 1, arg, buffer_len);
		if (length == escaped_len)
		{
			res[0] = res[escaped_len + 1] = '\'';
			res[escaped_len + 2] = '\0';
		}
		else
		{
			/*
			 * We don't know if the target database is using
			 * standard_conforming_strings, so we always use E'' strings.
			 */
			memmove(res + 2, res + 1, escaped_len);
			res[0] = ESCAPE_STRING_SYNTAX;
			res[1] = res[escaped_len + 2] = '\'';
			res[escaped_len + 3] = '\0';
		}
		ecpg_free(arg);
		return res;
	}
}

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

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

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

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

static int
next_insert(char *text, int pos, bool questionmarks)
{
	bool		string = false;
	int			p = pos;

	for (; text[p] != '\0'; p++)
	{
		if (text[p] == '\\')	/* escape character */
			p++;
		else if (text[p] == '\'')
			string = string ? false : true;
		else if (!string)
		{
			if (text[p] == '$' && isdigit((unsigned char) text[p + 1]))
			{
				/* this can be either a dollar quote or a variable */
				int			i;

				for (i = p + 1; isdigit((unsigned char) text[i]); i++)
					/* empty loop body */ ;
				if (!isalpha((unsigned char) text[i]) &&
					isascii((unsigned char) text[i]) && text[i] != '_')
					/* not dollar delimited quote */
					return p;
			}
			else if (questionmarks && text[p] == '?')
			{
				/* also allow old style placeholders */
				return p;
			}
		}
	}

	return -1;
}

static bool
ecpg_type_infocache_push(struct ECPGtype_information_cache ** cache, int oid, bool isarray, int lineno)
{
	struct ECPGtype_information_cache *new_entry
	= (struct ECPGtype_information_cache *) ecpg_alloc(sizeof(struct ECPGtype_information_cache), lineno);

	if (new_entry == NULL)
		return (false);

	new_entry->oid = oid;
	new_entry->isarray = isarray;
	new_entry->next = *cache;
	*cache = new_entry;
	return (true);
}

static enum ARRAY_TYPE
ecpg_is_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 */
		if (!ecpg_type_infocache_push(&(stmt->connection->cache_head), BOOLOID, ECPG_ARRAY_NONE, stmt->lineno))
			return (ECPG_ARRAY_ERROR);
		if (!ecpg_type_infocache_push(&(stmt->connection->cache_head), BYTEAOID, ECPG_ARRAY_NONE, stmt->lineno))
			return (ECPG_ARRAY_ERROR);
		if (!ecpg_type_infocache_push(&(stmt->connection->cache_head), CHAROID, ECPG_ARRAY_NONE, stmt->lineno))
			return (ECPG_ARRAY_ERROR);
		if (!ecpg_type_infocache_push(&(stmt->connection->cache_head), NAMEOID, not_an_array_in_ecpg, stmt->lineno))
			return (ECPG_ARRAY_ERROR);
		if (!ecpg_type_infocache_push(&(stmt->connection->cache_head), INT8OID, ECPG_ARRAY_NONE, stmt->lineno))
			return (ECPG_ARRAY_ERROR);
		if (!ecpg_type_infocache_push(&(stmt->connection->cache_head), INT2OID, ECPG_ARRAY_NONE, stmt->lineno))
			return (ECPG_ARRAY_ERROR);
		if (!ecpg_type_infocache_push(&(stmt->connection->cache_head), INT2VECTOROID, ECPG_ARRAY_VECTOR, stmt->lineno))
			return (ECPG_ARRAY_ERROR);
		if (!ecpg_type_infocache_push(&(stmt->connection->cache_head), INT4OID, ECPG_ARRAY_NONE, stmt->lineno))
			return (ECPG_ARRAY_ERROR);
		if (!ecpg_type_infocache_push(&(stmt->connection->cache_head), REGPROCOID, ECPG_ARRAY_NONE, stmt->lineno))
			return (ECPG_ARRAY_ERROR);
		if (!ecpg_type_infocache_push(&(stmt->connection->cache_head), TEXTOID, ECPG_ARRAY_NONE, stmt->lineno))
			return (ECPG_ARRAY_ERROR);
		if (!ecpg_type_infocache_push(&(stmt->connection->cache_head), OIDOID, ECPG_ARRAY_NONE, stmt->lineno))
			return (ECPG_ARRAY_ERROR);
		if (!ecpg_type_infocache_push(&(stmt->connection->cache_head), TIDOID, ECPG_ARRAY_NONE, stmt->lineno))
			return (ECPG_ARRAY_ERROR);
		if (!ecpg_type_infocache_push(&(stmt->connection->cache_head), XIDOID, ECPG_ARRAY_NONE, stmt->lineno))
			return (ECPG_ARRAY_ERROR);
		if (!ecpg_type_infocache_push(&(stmt->connection->cache_head), CIDOID, ECPG_ARRAY_NONE, stmt->lineno))
			return (ECPG_ARRAY_ERROR);
		if (!ecpg_type_infocache_push(&(stmt->connection->cache_head), OIDVECTOROID, ECPG_ARRAY_VECTOR, stmt->lineno))
			return (ECPG_ARRAY_ERROR);
		if (!ecpg_type_infocache_push(&(stmt->connection->cache_head), POINTOID, ECPG_ARRAY_VECTOR, stmt->lineno))
			return (ECPG_ARRAY_ERROR);
		if (!ecpg_type_infocache_push(&(stmt->connection->cache_head), LSEGOID, ECPG_ARRAY_VECTOR, stmt->lineno))
			return (ECPG_ARRAY_ERROR);
		if (!ecpg_type_infocache_push(&(stmt->connection->cache_head), PATHOID, ECPG_ARRAY_NONE, stmt->lineno))
			return (ECPG_ARRAY_ERROR);
		if (!ecpg_type_infocache_push(&(stmt->connection->cache_head), BOXOID, ECPG_ARRAY_VECTOR, stmt->lineno))
			return (ECPG_ARRAY_ERROR);
		if (!ecpg_type_infocache_push(&(stmt->connection->cache_head), POLYGONOID, ECPG_ARRAY_NONE, stmt->lineno))
			return (ECPG_ARRAY_ERROR);
		if (!ecpg_type_infocache_push(&(stmt->connection->cache_head), LINEOID, ECPG_ARRAY_VECTOR, stmt->lineno))
			return (ECPG_ARRAY_ERROR);
		if (!ecpg_type_infocache_push(&(stmt->connection->cache_head), FLOAT4OID, ECPG_ARRAY_NONE, stmt->lineno))
			return (ECPG_ARRAY_ERROR);
		if (!ecpg_type_infocache_push(&(stmt->connection->cache_head), FLOAT8OID, ECPG_ARRAY_NONE, stmt->lineno))
			return (ECPG_ARRAY_ERROR);
		if (!ecpg_type_infocache_push(&(stmt->connection->cache_head), ABSTIMEOID, ECPG_ARRAY_NONE, stmt->lineno))
			return (ECPG_ARRAY_ERROR);
		if (!ecpg_type_infocache_push(&(stmt->connection->cache_head), RELTIMEOID, ECPG_ARRAY_NONE, stmt->lineno))
			return (ECPG_ARRAY_ERROR);
		if (!ecpg_type_infocache_push(&(stmt->connection->cache_head), TINTERVALOID, ECPG_ARRAY_NONE, stmt->lineno))
			return (ECPG_ARRAY_ERROR);
		if (!ecpg_type_infocache_push(&(stmt->connection->cache_head), UNKNOWNOID, ECPG_ARRAY_NONE, stmt->lineno))
			return (ECPG_ARRAY_ERROR);
		if (!ecpg_type_infocache_push(&(stmt->connection->cache_head), CIRCLEOID, ECPG_ARRAY_NONE, stmt->lineno))
			return (ECPG_ARRAY_ERROR);
		if (!ecpg_type_infocache_push(&(stmt->connection->cache_head), CASHOID, ECPG_ARRAY_NONE, stmt->lineno))
			return (ECPG_ARRAY_ERROR);
		if (!ecpg_type_infocache_push(&(stmt->connection->cache_head), INETOID, ECPG_ARRAY_NONE, stmt->lineno))
			return (ECPG_ARRAY_ERROR);
		if (!ecpg_type_infocache_push(&(stmt->connection->cache_head), CIDROID, ECPG_ARRAY_NONE, stmt->lineno))
			return (ECPG_ARRAY_ERROR);
		if (!ecpg_type_infocache_push(&(stmt->connection->cache_head), BPCHAROID, ECPG_ARRAY_NONE, stmt->lineno))
			return (ECPG_ARRAY_ERROR);
		if (!ecpg_type_infocache_push(&(stmt->connection->cache_head), VARCHAROID, ECPG_ARRAY_NONE, stmt->lineno))
			return (ECPG_ARRAY_ERROR);
		if (!ecpg_type_infocache_push(&(stmt->connection->cache_head), DATEOID, ECPG_ARRAY_NONE, stmt->lineno))
			return (ECPG_ARRAY_ERROR);
		if (!ecpg_type_infocache_push(&(stmt->connection->cache_head), TIMEOID, ECPG_ARRAY_NONE, stmt->lineno))
			return (ECPG_ARRAY_ERROR);
		if (!ecpg_type_infocache_push(&(stmt->connection->cache_head), TIMESTAMPOID, ECPG_ARRAY_NONE, stmt->lineno))
			return (ECPG_ARRAY_ERROR);
		if (!ecpg_type_infocache_push(&(stmt->connection->cache_head), TIMESTAMPTZOID, ECPG_ARRAY_NONE, stmt->lineno))
			return (ECPG_ARRAY_ERROR);
		if (!ecpg_type_infocache_push(&(stmt->connection->cache_head), INTERVALOID, ECPG_ARRAY_NONE, stmt->lineno))
			return (ECPG_ARRAY_ERROR);
		if (!ecpg_type_infocache_push(&(stmt->connection->cache_head), TIMETZOID, ECPG_ARRAY_NONE, stmt->lineno))
			return (ECPG_ARRAY_ERROR);
		if (!ecpg_type_infocache_push(&(stmt->connection->cache_head), ZPBITOID, ECPG_ARRAY_NONE, stmt->lineno))
			return (ECPG_ARRAY_ERROR);
		if (!ecpg_type_infocache_push(&(stmt->connection->cache_head), VARBITOID, ECPG_ARRAY_NONE, stmt->lineno))
			return (ECPG_ARRAY_ERROR);
		if (!ecpg_type_infocache_push(&(stmt->connection->cache_head), NUMERICOID, ECPG_ARRAY_NONE, stmt->lineno))
			return (ECPG_ARRAY_ERROR);
	}

	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 *) ecpg_alloc(strlen("select typlen from pg_type where oid= and typelem<>0") + 11, stmt->lineno);
	if (array_query == NULL)
		return (ECPG_ARRAY_ERROR);

	sprintf(array_query, "select typlen from pg_type where oid=%d and typelem<>0", type);
	query = PQexec(stmt->connection->connection, array_query);
	ecpg_free(array_query);
	if (!ecpg_check_PQresult(query, stmt->lineno, stmt->connection->connection, stmt->compat))
		return (ECPG_ARRAY_ERROR);
	else 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 (ecpg_dynamic_type(type) == SQL3_CHARACTER ||
				ecpg_dynamic_type(type) == SQL3_CHARACTER_VARYING)
			{
				/*
				 * arrays of character strings are not yet implemented
				 */
				isarray = ECPG_ARRAY_NONE;
			}
		}
		PQclear(query);
	}
	else
		return (ECPG_ARRAY_ERROR);

	ecpg_type_infocache_push(&(stmt->connection->cache_head), type, isarray, stmt->lineno);
	ecpg_log("ecpg_is_type_an_array line %d: TYPE database: %d C: %d array: %s\n", stmt->lineno, type, var->type, isarray ? "Yes" : "No");
	return isarray;
}


bool
ecpg_store_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;

	if ((isarray = ecpg_is_type_an_array(PQftype(results, act_field), stmt, var)) == ECPG_ARRAY_ERROR)
	{
		ecpg_raise(stmt->lineno, ECPG_OUT_OF_MEMORY, ECPG_SQLSTATE_ECPG_OUT_OF_MEMORY, NULL);
		return false;
	}

	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))
		{
			ecpg_log("ecpg_store_result line %d: Incorrect number of matches: %d don't fit into array of %d\n",
					 stmt->lineno, ntuples, var->arrsize);
			ecpg_raise(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)
		{
			ecpg_raise(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 *);
				}
				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;
		}
		ecpg_log("ecpg_store_result: line %d: allocating memory for %d tuples\n", stmt->lineno, ntuples);
		var->value = (char *) ecpg_alloc(len, stmt->lineno);
		if (!var->value)
			return false;
		*((char **) var->pointer) = var->value;
		ecpg_add_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 *) ecpg_alloc(len, stmt->lineno);
		if (!var->ind_value)
			return false;
		*((char **) var->ind_pointer) = var->ind_value;
		ecpg_add_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 */