NAME

sqlbox_close — close a database

LIBRARY

library “sqlbox”

SYNOPSIS

#include <stdint.h>
#include <sqlbox.h>

int
sqlbox_close(struct sqlbox *box, size_t id);

DESCRIPTION

Close a database with the database id as returned from sqlbox_open(3). If id is zero, the last-opened database is used. The caller must have a role capable of opening and closing the given database source. Once closed, subsequent calls to sqlbox_close() with the same identifier will fail.

If sqlbox_close() is not explicitly called, the database will be implicitly closed at sqlbox_free(3). This is not considered an error, as a common usage pattern is a role with permission opening the database, shedding its role, then the close being relegated to the full destruction of the box.

RETURN VALUES

sqlbox_close() returns zero if communication with box fails. Otherwise, it returns non-zero on success.

If closing the database fails (not open or does not exist, statements not finalised, a transaction still open), subsequent box access will fail. Use sqlbox_ping(3) to check explicitly.

If sqlbox_close() fails, box is no longer accessible beyond sqlbox_ping(3) and sqlbox_free(3).

EXAMPLES

To simply open and close an in-memory database:

struct sqlbox *p;
struct sqlbox_src srcs[] = {
  { .fname = (char *)":memory:",
    .mode = SQLBOX_SRC_RWC },
};
struct sqlbox_cfg cfg;
size_t id;

memset(&cfg, 0, sizeof(struct sqlbox_cfg));
cfg.msg.func_short = warnx;
cfg.srcs.srcsz = 1;
cfg.srcs.srcs = srcs;

if ((p = sqlbox_alloc(&cfg)) == NULL)
  errx(EXIT_FAILURE, "sqlbox_alloc");
if (!(id = sqlbox_open(p, 0)))
  errx(EXIT_FAILURE, "sqlbox_open");
/* Perform work... */
if (!sqlbox_close(p, id))
  errx(EXIT_FAILURE, "sqlbox_close");
sqlbox_free(p);

To let sqlbox_free(3) handle closing the database for role-shedding:

struct sqlbox *p;
struct sqlbox_src srcs[] = {
  { .fname = (char *)":memory:",
    .mode = SQLBOX_SRC_RWC },
};
struct sqlbox_role roles[] = {
  { .roles = (size_t[]){ 0, 1 },
    .rolesz = 2,
    .stmtsz = 0,
    .srcs = (size_t[]){ 0 },
    .srcsz = 1 },
  { .rolesz = 0,
    .stmtsz = 0,
    .srcsz = 0 }
};
struct sqlbox_cfg cfg;
size_t id;

memset(&cfg, 0, sizeof(struct sqlbox_cfg));
cfg.msg.func_short = warnx;
cfg.srcs.srcsz = 1;
cfg.srcs.srcs = srcs;
cfg.roles.roles = roles;
cfg.roles.rolesz = 2;
cfg.roles.defrole = 0;

if ((p = sqlbox_alloc(&cfg)) == NULL)
  errx(EXIT_FAILURE, "sqlbox_alloc");
if (!(id = sqlbox_open(p, 0)))
  errx(EXIT_FAILURE, "sqlbox_open");
if (!sqlbox_role(p, 1))
  errx(EXIT_FAILURE, "sqlbox_role");
/* Perform work... */
sqlbox_free(p);

In the last example, the default role is able to transition into the new role, which is not able to close the database.

SEE ALSO

sqlbox_open(3), sqlbox_ping(3)