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/* $Header: /cvsroot/pgsql/src/interfaces/ecpg/ecpglib/prepare.c,v 1.2 2003/06/15 04:07:58 momjian Exp $ */
#define POSTGRES_ECPG_INTERNAL
#include "postgres_fe.h"
#include <ctype.h>
#include "ecpgtype.h"
#include "ecpglib.h"
#include "ecpgerrno.h"
#include "extern.h"
#include "sqlca.h"
static struct prepared_statement
{
char *name;
struct statement *stmt;
struct prepared_statement *next;
} *prep_stmts = NULL;
static bool
isvarchar(unsigned char c)
{
if (isalnum(c))
return true;
if (c == '_' || c == '>' || c == '-' || c == '.')
return true;
if (c >= 128)
return true;
return (false);
}
static void
replace_variables(char *text)
{
char *ptr = text;
bool string = false;
for (; *ptr != '\0'; ptr++)
{
if (*ptr == '\'')
string = string ? false : true;
if (!string && *ptr == ':')
{
*ptr = '?';
for (++ptr; *ptr && isvarchar(*ptr); ptr++)
*ptr = ' ';
}
}
}
/* handle the EXEC SQL PREPARE statement */
bool
ECPGprepare(int lineno, char *name, char *variable)
{
struct statement *stmt;
struct prepared_statement *this;
/* check if we already have prepared this statement */
for (this = prep_stmts; this != NULL && strcmp(this->name, name) != 0; this = this->next);
if (this)
{
bool b = ECPGdeallocate(lineno, name);
if (!b)
return false;
}
this = (struct prepared_statement *) ECPGalloc(sizeof(struct prepared_statement), lineno);
if (!this)
return false;
stmt = (struct statement *) ECPGalloc(sizeof(struct statement), lineno);
if (!stmt)
{
ECPGfree(this);
return false;
}
/* create statement */
stmt->lineno = lineno;
stmt->connection = NULL;
stmt->command = ECPGstrdup(variable, lineno);
stmt->inlist = stmt->outlist = NULL;
/* if we have C variables in our statment replace them with '?' */
replace_variables(stmt->command);
/* add prepared statement to our list */
this->name = ECPGstrdup(name, lineno);
this->stmt = stmt;
if (prep_stmts == NULL)
this->next = NULL;
else
this->next = prep_stmts;
prep_stmts = this;
return true;
}
/* handle the EXEC SQL DEALLOCATE PREPARE statement */
bool
ECPGdeallocate(int lineno, char *name)
{
struct prepared_statement *this,
*prev;
/* check if we really have prepared this statement */
for (this = prep_stmts, prev = NULL; this != NULL && strcmp(this->name, name) != 0; prev = this, this = this->next);
if (this)
{
/* okay, free all the resources */
ECPGfree(this->name);
ECPGfree(this->stmt->command);
ECPGfree(this->stmt);
if (prev != NULL)
prev->next = this->next;
else
prep_stmts = this->next;
ECPGfree(this);
return true;
}
ECPGraise(lineno, ECPG_INVALID_STMT, name);
return false;
}
bool
ECPGdeallocate_all(int lineno)
{
/* deallocate all prepared statements */
while (prep_stmts != NULL)
{
bool b = ECPGdeallocate(lineno, prep_stmts->name);
if (!b)
return false;
}
return true;
}
/* return the prepared statement */
char *
ECPGprepared_statement(char *name)
{
struct prepared_statement *this;
for (this = prep_stmts; this != NULL && strcmp(this->name, name) != 0; this = this->next);
return (this) ? this->stmt->command : NULL;
}
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