This will probably get mangled by email systems line wrapping everything, but it looks like on the forum it keeps the format.
Below is the C code I wrote for basic access of my database. If you have any suggestions, or looks like I missed something, feel free to comment. There is a header file not included here that has an enumeration of error codes, but they are easily replaced and obvious.
```
/* ********************** */
/* SQLite Access routines */
/* ********************** */
#include <stdio.h>
#include <ctype.h>
#include <errno.h>
#include <math.h>
#include <stdlib.h>
#include <string.h>
#include <mem.h>
#include <io.h>
#include <fcntl.h>
#include <sys/types.h>
#include <sys/stat.h>
#include "sqlite3.h"
#define SQLMAXSIZE BUFSIZE /* max number of bytes in a sql statement */
typedef struct
{
char fn[MAXFILENAMESIZE + 1]; /* name of the database */
char isopen; /* flag whether the database is open */
char exists; /* flag set if database exists on disk */
char sql[SQLMAXSIZE]; /* the sql string */
int sqllen; /* length of the sql string */
sqlite3 *db; /* the opaque sqlite database structure */
sqlite3_stmt *stmt; /* the prepared statement */
int rows; /* number of rows returned by statement */
} TXTDB;
TXTDB txtdb; /* the database */
char txtdbtemp[SQLMAXSIZE + 2]; /* temp string */
/* ********************************************************** */
/* open txtdb and init variables. called at start of program */
/* returns 0 if everything OK */
/* returns 1 if file did not exist and was created */
/* this means the database tables need to be created */
/* ********************************************************** */
int txtdb_open(void)
{
int i;
int f;
char cflag; /* create flag if set then file does not exist */
if (txtdb.isopen)
{
write_errfile("Attempt to open txtdb which is already open");
exit(TXTTLS_ERROR_31);
}
if (txtdb.db)
{
write_errfile("txtdb.db not null in txtdb_open");
exit(TXTTLS_ERROR_31);
}
/* first try opening the file to see if it exists */
cflag = 0;
f = open(txtdb.fn, O_RDWR | O_BINARY, S_IREAD | S_IWRITE);
if (f == -1)
{
/* if an error occurs then cannot proceed, so write error message */
switch (errno)
{
case EACCES:
write_errfile("txtdb Open Error: Permission Denied");
exit(TXTTLS_ERROR_33);
case EINVACC:
write_errfile("txtdb Open Error: Invalid Access Code");
exit(TXTTLS_ERROR_33);
case EMFILE:
write_errfile("txtdb Open Error: Too Many Files Open");
exit(TXTTLS_ERROR_33);
case ENOENT:
write_errfile("txtdb file does not exist. Creating txtdb");
cflag = 1; /* set flag indicating that file is being created */
break;
default:
write_errfile("txtdb Open Error: Unknown Error");
exit(TXTTLS_ERROR_33);
}
}
close(f); /* close the handle */
i = sqlite3_open(txtdb.fn, &txtdb.db); /* open the database */
if (i != SQLITE_OK)
{
sprintf(txtdbtemp, "txtdb Open Error: error during database open %d", i);
write_errfile(txtdbtemp);
exit(TXTTLS_ERROR_33);
}
if (!txtdb.db)
{
write_errfile("txtdb Open Error: txtdb is null after open");
exit(TXTTLS_ERROR_33);
}
txtdb.isopen = 1; /* set open flag */
txtdb.exists = cflag; /* save the create flag */
return cflag;
}
/* ************************************ */
/* Close the previously opened database */
/* ************************************ */
void txtdb_close(void)
{
int i;
if (!txtdb.isopen)
{
if (txtdb.db)
{
write_errfile("txtdb Close Error: txtdb.db not null and not flagged as open");
exit(TXTTLS_ERROR_34);
}
write_errfile("txtdb Close Error: txtdb.db is null and not flagged as open");
exit(TXTTLS_ERROR_34);
}
do
{
i = sqlite3_close(txtdb.db);
if ((i != SQLITE_BUSY) && (i != SQLITE_OK))
{
sprintf(txtdbtemp, "txtdb Close Error: error during database Close %d", i);
write_errfile(txtdbtemp);
exit(TXTTLS_ERROR_34);
}
}
while (i == SQLITE_BUSY);
txtdb.isopen = 0;
txtdb.db = 0;
txtdb.exists = 0;
}
/* ***************************************************** */
/* does the sqlite3_prepare_v2() with error checking */
/* returns SQLITE_OK if ready for a step. */
/* writes to errfile, but does not exit if sql too long */
/* if sql is too long then returns SQLITE_ERROR */
/* any other error, the error code is returned */
/* **************************************************** */
int txtdb_prepare(char *sql)
{
int i;
txtdb.sqllen = strlen(sql); /* get and check length of sql */
if (txtdb.sqllen > SQLMAXSIZE - 1)
{
write_errfile("SQL Too Long:");
write_errfile(sql);
return SQLITE_ERROR;
}
strcpy(txtdb.sql, sql); /* save the sql into the structure */
if (!txtdb.isopen)
{
write_errfile("txtdb prepare without database open");
exit(TXTTLS_ERROR_35);
}
if (txtdb.db == 0)
{
write_errfile("txtdb prepare with null database handle");
exit(TXTTLS_ERROR_36);
}
i = sqlite3_prepare_v2(txtdb.db, sql, (txtdb.sqllen + 1), &txtdb.stmt, 0);
return i;
}
```