+2000-05-07 Mark Kettenis <kettenis@gnu.org>
+
+ * nss/nss_db/db-open.c: Cleanup and add comments. Pretty print.
+ Remove duplicate <errno.h> include. Remove inclusion of
+ <libintl.h> and "nsswitch.h".
+ (set_cloexec_flag): New function, broken out of dbopen.
+ (dbopen): Changed return type to `enum
+ nss_status'. Mostly rewritten to make sure that we do not report
+ NSS_STATUS_SUCCESS if something went wrong. Remove unnecessary casts.
+ (internal_setent): Change return type to nss_status.
+ Document, and make sure that the function
+ behaves accordingly. Make dynamically loading the database
+ library really thread-safe and return NSS_STATUS_UNAVAIL if it
+ failed.
+ (db_cursor): Return ENOMEM is memory allocation failed. Remove
+ unecessary casts.
+ * nss/nss_db/dummy-db.h: Add copyright notice. Improve
+ documentation.
+ (struct dbc24, struct dbc27): Use DBT type in parameter lists for
+ c_get function member.
+ * nss/nss_db/nss_db.h: Add and tweak some comments.
+ (DBT): Move typedef before NSS_DBC typedef.
+ (NSS_DBC, NSS_DB): Use DBT in function member parameter lists.
+
2000-05-07 H.J. Lu <hjl@gnu.org>
* csu/initfini.c: Moved to ....
found:
/* The translation was found at index ACT. If we have to convert the
string to use a different character set, this is the time. */
- result = (char *) domain->data
- + W (domain->must_swap, domain->trans_tab[act].offset);
+ result = ((char *) domain->data
+ + W (domain->must_swap, domain->trans_tab[act].offset));
#if defined _LIBC || HAVE_ICONV
if (
#include <errno.h>
#include <fcntl.h>
#include <dlfcn.h>
-#include <errno.h>
#include <stdlib.h>
-#include <libintl.h>
+#include <string.h>
#include <bits/libc-lock.h>
#include "dummy-db.h"
-#include "nsswitch.h"
#include "nss_db.h"
/* This file contains the functions used to open and close the databases
- read by the rest of libnss_db. They are not thread safe; the caller
- must handle locking.
+ read by the rest of libnss_db. Not all of them are thread safe;
+ make sure the caller does the appropriate locking.
We dynamically load the database library, so that it does not have
- to be present when glibc is compiled. Once loaded, libdb is never
- unloaded again unless this library is unloaded (from the free_mem
- routine in nsswitch.c) - we catch the unload by providing a shlib
- destructor. (XXX Does it work?) */
-
+ to be present when glibc is compiled. Once loaded, the database
+ library is never never unloaded again until the libnss_db module is
+ unloaded (from the free_mem routine in nsswitch.c) -- we catch the
+ unload by providing a shlib destructor. (XXX Does that actually
+ work?) */
+
+/* Handle for the shared Berkeley DB library. If non-null, the
+ database library is completely loaded and ready to be used by
+ multithreaded code. */
static void *libdb_handle;
+
+/* The version of the Berkeley DB library we are using. */
enum {
nodb,
db24,
db27,
db30
} libdb_version;
+
+/* Pointer to the db_open function. For use with DB 2.x. */
static int (*libdb_db_open) (const char *, int,
uint32_t, int, void *, void *, void **);
+/* Pointer to the db_create function. For use with DB 3.x. */
static int (*libdb_db_create) (void *, void *, uint32_t);
/* Constants which vary from version to version are actually variables
/* Locks the static variables in this file. */
__libc_lock_define_initialized (static, lock)
-/* Dynamically load the database library.
+/* Dynamically load the database library. Return zero if successful,
+ non-zero if no suitable version of the library could be loaded.
+ Must be called with the above lock held if it might run in a
+ multithreaded context.
+
We try currently:
- libdb.so.3: the name used by glibc 2.1
- libdb-3.0.so: the name used by db-3.0.x
and maybe others in the future. */
-
-int
+
+enum nss_status
load_db (void)
{
static const char *libnames[] = { "libdb.so.3", "libdb-3.0.so" };
if (libdb_handle == NULL)
continue;
- /* db 3.0 has db_create instead of db_open. */
+ /* DB 3.0 has db_create instead of db_open. */
libdb_db_create = dlsym (libdb_handle, "db_create");
if (libdb_db_create == NULL)
- /* db 2.x uses db_open. */
+ /* DB 2.x uses db_open. */
libdb_db_open = dlsym (libdb_handle, "db_open");
if (libdb_db_open != NULL || libdb_db_create != NULL)
db_rdonly = DB2x_RDONLY;
}
break;
+
case 3:
/* Sanity check: Do we have db_create? */
if (libdb_db_create != NULL)
db_rdonly = DB30_RDONLY;
}
break;
+
default:
break;
}
}
+
if (libdb_version != nodb)
- return 0;
+ return NSS_STATUS_SUCCESS;
/* Clear variables. */
libdb_db_open = NULL;
}
(void) dlerror ();
- return 1;
+ return NSS_STATUS_UNAVAIL;
+}
+
+/* Set the `FD_CLOEXEC' flag of FD. Return 0 on success, or -1 on
+ error with `errno' set. */
+static int
+set_cloexec_flag (int fd)
+{
+ int oldflags = fcntl (fd, F_GETFD, 0);
+
+ if (oldflags < 0)
+ return oldflags;
+
+ oldflags |= FD_CLOEXEC;
+
+ return fcntl (fd, F_SETFD, oldflags);
}
/* Make sure we don't use the library anymore once we are shutting down. */
}
}
+/* Open the database stored in FILE. If succesful, store the database
+ handle in *DBP and return NSS_STATUS_SUCCESS. On failure, return
+ the appropriate lookup status. */
enum nss_status
internal_setent (const char *file, NSS_DB **dbp)
{
{
__libc_lock_lock (lock);
- status = load_db ();
+ if (libdb_db_open == NULL && libdb_db_create == NULL)
+ status = load_db ();
__libc_lock_unlock (lock);
-
- if (status != 0)
- return status;
}
- status = dbopen (file, db_rdonly, 0, dbp);
+ if (status == NSS_STATUS_SUCCESS)
+ status = dbopen (file, db_rdonly, 0, dbp);
}
return status;
}
-/* Close the database file. */
+/* Close the database *DBP. */
void
internal_endent (NSS_DB **dbp)
{
NSS_DB *db = *dbp;
+
if (db != NULL)
{
DL_CALL_FCT (db->close, (db->db, 0));
}
}
+/* Allocate a cursor for database DB and transaction TXN. On success,
+ store the cursor in *DBCP and return zero. Otherwise return an
+ error value. */
int
db_cursor (void *db, void *txn, NSS_DBC **dbcp)
{
- void *ptr;
- NSS_DBC *dbc = NULL;
+ NSS_DBC *dbc;
int ret;
+ dbc = (NSS_DBC *) malloc (sizeof (NSS_DBC));
+ if (dbc == NULL)
+ return ENOMEM;
+
switch (libdb_version)
{
case db24:
- ret = ((struct db24 *) db)->cursor (db, txn, &ptr);
+ ret = ((struct db24 *) db)->cursor (db, txn, &dbc->cursor);
+
+ if (ret == 0)
+ dbc->c_get = ((struct dbc24 *) dbc->cursor)->c_get;
break;
+
case db27:
- ret = ((struct db27 *) db)->cursor (db, txn, &ptr, 0);
+ ret = ((struct db27 *) db)->cursor (db, txn, &dbc->cursor, 0);
+
+ if (ret == 0)
+ dbc->c_get = ((struct dbc27 *) dbc->cursor)->c_get;
break;
+
case db30:
- ret = ((struct db30 *) db)->cursor (db, txn, &ptr, 0);
+ ret = ((struct db30 *) db)->cursor (db, txn, &dbc->cursor, 0);
+
+ if (ret == 0)
+ dbc->c_get = ((struct dbc30 *) dbc->cursor)->c_get;
break;
+
default:
abort ();
}
- if (ret == 0)
+ if (ret != 0)
{
- dbc = (NSS_DBC *) malloc (sizeof (NSS_DBC));
- if (dbc == NULL)
- return 1;
- dbc->cursor = ptr;
-
- switch (libdb_version)
- {
- case db24:
- dbc->c_get =
- (int (*) (void *, void *, void *, uint32_t))
- ((struct dbc24 *) ptr)->c_get;
- break;
- case db27:
- dbc->c_get =
- (int (*) (void *, void *, void *, uint32_t))
- ((struct dbc27 *) ptr)->c_get;
- break;
- case db30:
- dbc->c_get =
- (int (*) (void *, void *, void *, uint32_t))
- ((struct dbc30 *) ptr)->c_get;
- default:
- abort ();
- }
+ free (dbc);
+ return ret;
}
*dbcp = dbc;
- return ret;
+ return 0;
}
+/* Open the database in FNAME, for access specified by FLAGS. If
+ opening the database causes the file FNAME to be created, it is
+ created with MODE. If succesful, store the database handle in *DBP
+ and return NSS_STATUS_SUCCESS. On failure, return the appropriate
+ lookup status. */
int
dbopen (const char *fname, int oper, int mode, NSS_DB **dbp)
{
int err;
- int result;
int fd;
- void *odb;
- enum nss_status status = NSS_STATUS_SUCCESS;
NSS_DB *db;
+ /* Construct the object we pass up. */
+ db = (NSS_DB *) calloc (1, sizeof (NSS_DB));
+ if (db == NULL)
+ return NSS_STATUS_UNAVAIL;
+
+ /* Initialize the object. */
+ db->cursor = db_cursor;
+
/* Actually open the database. */
switch (libdb_version)
{
case db24:
case db27:
err = DL_CALL_FCT (libdb_db_open,
- (fname, DB_BTREE, oper, mode, NULL, NULL, &odb));
+ (fname, DB_BTREE, oper, mode, NULL, NULL, &db->db));
if (err != 0)
+ goto fail;
+
+ if (libdb_version)
{
- __set_errno (err);
- *dbp = NULL;
- return err == EAGAIN ? NSS_STATUS_TRYAGAIN : NSS_STATUS_UNAVAIL;
+ db->close = ((struct db24 *) db->db)->close;
+ db->fd = ((struct db24 *) db->db)->fd;
+ db->get = ((struct db24 *) db->db)->get;
+ db->put = ((struct db24 *) db->db)->put;
+ }
+ else
+ {
+ db->close = ((struct db27 *) db->db)->close;
+ db->fd = ((struct db27 *) db->db)->fd;
+ db->get = ((struct db27 *) db->db)->get;
+ db->put = ((struct db27 *) db->db)->put;
}
break;
+
case db30:
- err = DL_CALL_FCT (libdb_db_create, (&odb, NULL, 0));
+ err = DL_CALL_FCT (libdb_db_create, (db->db, NULL, 0));
if (err != 0)
- {
- __set_errno (err);
- *dbp = NULL;
- return err == EAGAIN ? NSS_STATUS_TRYAGAIN : NSS_STATUS_UNAVAIL;
- }
- err = ((struct db30 *) odb)->open (odb, fname, NULL, DB_BTREE,
- oper, mode);
+ goto fail;
+
+ db->close = ((struct db30 *) db->db)->close;
+ db->fd = ((struct db30 *) db->db)->fd;
+ db->get = ((struct db30 *) db->db)->get;
+ db->put = ((struct db30 *) db->db)->put;
+
+ err = ((struct db30 *) db->db)->open (db->db, fname, NULL, DB_BTREE,
+ oper, mode);
if (err != 0)
- {
- __set_errno (err);
- /* Free all resources. */
- ((struct db30 *) odb)->close (odb, 0);
- *dbp = NULL;
- return NSS_STATUS_UNAVAIL;
- }
+ goto fail;
break;
+
default:
abort ();
}
-
- /* Construct the object we pass up. */
- db = (NSS_DB *) malloc (sizeof (NSS_DB));
- if (db != NULL)
- {
- db->db = odb;
- /* The functions are at different positions for the different
- versions. Sigh. */
- switch (libdb_version)
- {
- case db24:
- db->close =
- (int (*) (void *, uint32_t)) ((struct db24 *) odb)->close;
- db->fd =
- (int (*) (void *, int *)) ((struct db24 *) odb)->fd;
- db->get =
- (int (*) (void *, void *, void *, void *, uint32_t))
- ((struct db24 *) odb)->get;
- db->put =
- (int (*) (void *, void *, void *, void *, uint32_t))
- ((struct db24 *) odb)->put;
- break;
- case db27:
- db->close =
- (int (*) (void *, uint32_t)) ((struct db27 *) odb)->close;
- db->fd =
- (int (*) (void *, int *)) ((struct db27 *) odb)->fd;
- db->get =
- (int (*) (void *, void *, void *, void *, uint32_t))
- ((struct db27 *) odb)->get;
- db->put =
- (int (*) (void *, void *, void *, void *, uint32_t))
- ((struct db27 *) odb)->put;
- break;
- case db30:
- db->close =
- (int (*) (void *, uint32_t)) ((struct db30 *) odb)->close;
- db->fd =
- (int (*) (void *, int *)) ((struct db30 *) odb)->fd;
- db->get =
- (int (*) (void *, void *, void *, void *, uint32_t))
- ((struct db30 *) odb)->get;
- db->put =
- (int (*) (void *, void *, void *, void *, uint32_t))
- ((struct db30 *) odb)->put;
- break;
- default:
- abort ();
- }
- db->cursor = db_cursor;
+ /* We have to make sure the file is `closed on exec'. */
+ err = DL_CALL_FCT (db->fd, (db->db, &fd));
+ if (err != 0)
+ goto fail;
+ if (set_cloexec_flag (fd) < 0)
+ goto fail;
- /* We have to make sure the file is `closed on exec'. */
- err = DL_CALL_FCT (db->fd, (odb, &fd));
- if (err != 0)
- {
- __set_errno (err);
- result = -1;
- }
- else
- {
- int flags = result = fcntl (fd, F_GETFD, 0);
+ *dbp = db;
- if (result >= 0)
- {
- flags |= FD_CLOEXEC;
- result = fcntl (fd, F_SETFD, flags);
- }
- }
- if (result < 0)
- {
- /* Something went wrong. Close the stream and return a
- failure. */
- DL_CALL_FCT (db->close, (odb, 0));
- free (db);
- status = NSS_STATUS_UNAVAIL;
- db = NULL;
- }
+ return NSS_STATUS_UNAVAIL;
+
+ fail:
+ /* Something went wrong. Close the database if necessary. */
+ if (db)
+ {
+ if (db->db && db->close)
+ DL_CALL_FCT (db->close, (db->db, 0));
+ free (db);
}
- *dbp = db;
-
- return status;
+
+ /* Make sure `errno' is set. */
+ if (err)
+ __set_errno (err);
+
+ return err == EAGAIN ? NSS_STATUS_TRYAGAIN : NSS_STATUS_UNAVAIL;
}
+/* Constants and structures from the various Berkeley DB releases.
+ Copyright (C) 1999, 2000 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Library General Public License as
+ published by the Free Software Foundation; either version 2 of the
+ License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Library General Public License for more details.
+
+ You should have received a copy of the GNU Library General Public
+ License along with the GNU C Library; see the file COPYING.LIB. If not,
+ write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ Boston, MA 02111-1307, USA. */
+
#include <stdint.h>
#include "nss_db.h"
-/* This file contains dummy definitions of the DB structure of the
- Berkeley DB. We are only interested in the function pointers since
- this is the interface to the database. Unfortunately the structure
- changed over time and we have to take this into account. */
+/* This file contains dummy definitions for various constants and
+ structures from the Berkeley release. We only provide those
+ definitions that are actually needed. In case of the structures,
+ we're only interested in the function pointers, since that's the
+ interface to the database. Unfortunately the structures have been
+ changed several times. */
-/* The values to select the database type are unchanged over the version.
- Define only what we really need. */
+/* The value for the btree database type has not been changed (yet?). */
#define DB_BTREE (1)
-/* Permission flags. */
+/* Permission flags for all 2.x releases. */
#define DB2x_RDONLY 0x010000
-/* Access methods. */
+/* The error values for all 2.x releases. */
+#define DB2x_KEYEXIST ( -3)
+#define DB2x_NOTFOUND ( -7)
+
+/* For all 2.x releases up to 2.6.3 we can use the same definitions.
+ We'll refer to them as 2.4 since that's the version distributed
+ with glibc 2.1. */
+
+/* Access methods from version 2.4. */
#define DB24_FIRST 0x000020
#define DB24_NEXT 0x000800
#define DB24_NOOVERWRITE 0x001000
-/* The error values that are needed. */
-#define DB2x_KEYEXIST ( -3)
-#define DB2x_NOTFOUND ( -7)
-
+/* Permission flags from version 2.4. */
+#define DB24_TRUNCATE 0x080000
-/* This is for the db-2.x version up to 2.x.y. We use the name `db24' since
- this is the version which was shipped with glibc 2.1. */
+/* The DB structure from version 2.4. */
struct db24
{
void *mutexp;
uint32_t flags;
};
-
+/* The DBC structure for the 2.4 release. */
struct dbc24
{
void *dbp;
void *internal;
void *c_close;
void *c_del;
- int (*c_get) (void *, void *, void *, uint32_t);
+ int (*c_get) (void *, DBT *, DBT *, uint32_t);
void *c_put;
};
-/* Flags which changed. */
-#define DB24_TRUNCATE 0x080000
+/* The 2.7 release is slighty different. */
+/* Access methods from version 2.7. */
+#define DB27_FIRST 7
+#define DB27_NEXT 15
+#define DB27_NOOVERWRITE 17
+
+/* Permission flags from version 2.7. */
+#define DB27_TRUNCATE 0x020000
-/* Versions for 2.7, slightly incompatible with version 2.4. */
+/* The DB structure from version 2.7. */
struct db27
{
void *mutexp;
int (*del) (void *, void *, DBT *, uint32_t);
int (*fd) (void *, int *);
int (*get) (void *, void *, DBT *, DBT *, uint32_t);
- int (*join) (void *, void **, uint32_t, void **);
+ int (*join) (void *, void **, uint32_t, void **);
int (*put) (void *, void *, DBT *, DBT *, uint32_t);
int (*stat) (void *, void *, void *(*)(size_t), uint32_t);
int (*sync) (void *, uint32_t);
uint32_t flags;
};
-
+/* The DBC structure for version 2.7. */
struct dbc27
{
void *dbp;
void *c_am_destroy;
void *c_close;
void *c_del;
- int (*c_get) (void *, void *, void *, uint32_t);
+ int (*c_get) (void *, DBT *, DBT *, uint32_t);
void *c_put;
void *internal;
uint32_t flags;
};
-/* Flags which changed. */
-#define DB27_TRUNCATE 0x020000
+/* Version 3.0 is mostly incompatible with 2.x. */
-/* Access methods. */
-#define DB27_FIRST 7
-#define DB27_NEXT 15
-#define DB27_NOOVERWRITE 17
+/* Access methods from version 3.0. */
+#define DB30_FIRST 9
+#define DB30_NEXT 17
+#define DB30_NOOVERWRITE 20
-/* Versions for 3.0, incompatible with version 2.x. */
+/* Error values from version 3.0. */
+#define DB30_KEYEXIST (-30997)
+#define DB30_NOTFOUND (-30994)
+
+/* Permission flags from version 3.0. */
+#define DB30_RDONLY 0x000010
+#define DB30_TRUNCATE 0x020000
+
+/* The DB structure from version 3.0. */
struct db30
{
size_t pgsize;
int (*stat) (void *, void *, void *(*)(size_t), uint32_t);
int (*sync) (void *, uint32_t);
int (*upgrade) (void *, const char *, uint32_t);
-
+
int (*set_bt_compare) (void *, int (*)(const DBT *, const DBT *));
int (*set_bt_maxkey) (void *, uint32_t);
int (*set_bt_minkey) (void *, uint32_t);
int (*set_bt_prefix) (void *, size_t (*)(const DBT *, const DBT *));
-
+
int (*set_h_ffactor) (void *, uint32_t);
int (*set_h_hash) (void *, uint32_t (*)(const void *, uint32_t));
int (*set_h_nelem) (void *, uint32_t);
-
+
int (*set_re_delim) (void *, int);
int (*set_re_len) (void *, uint32_t);
int (*set_re_pad) (void *, int);
uint32_t flags;
};
-
+/* The DBC structure from version 3.0. */
struct dbc30
{
void *dbp;
void *internal;
uint32_t flags;
};
-
-/* Flags which changed. */
-#define DB30_TRUNCATE 0x020000
-
-/* Access methods. */
-#define DB30_FIRST 9
-#define DB30_NEXT 17
-#define DB30_NOOVERWRITE 20
-
-/* Permission flags are changed. */
-#define DB30_RDONLY 0x000010
-
-
-/* The error values that are needed. */
-#define DB30_KEYEXIST (-30997)
-#define DB30_NOTFOUND (-30994)
#ifndef _NSS_DB_H
#define _NSS_DB_H 1
+#include <nss.h>
#include <stdint.h>
/* Variables which keep track of the error values. */
extern int db_keyexist;
extern int db_notfound;
-/* Constants which vary from version to version are actually variables
- here. */
+/* This flag is the same for all versions of the Berkeley DB library. */
+#define DB_CREATE 0x000001
+
+/* But constants which vary from version to version are actually
+ variables here. */
extern int db_first;
extern int db_next;
extern int db_nooverwrite;
extern int db_truncate;
extern int db_rdonly;
-/* Flags are also unchanged. */
-#define DB_CREATE 0x000001
-
+/* The `DBT' type is the same in all versions we support. */
+typedef struct
+{
+ void *data;
+ uint32_t size;
+ uint32_t ulen;
+ uint32_t dlen;
+ uint32_t doff;
+ uint32_t flags;
+} DBT;
-/* Similarly we have to handle the cursor object. It is also very
- different from version to version. */
+/* But the cursor object is very different from version to version. */
typedef struct
{
void *cursor;
- int (*c_get) (void *, void *, void *, uint32_t);
+ int (*c_get) (void *, DBT *, DBT *, uint32_t);
} NSS_DBC;
+/* We need a helper function for it. */
+extern int db_cursor (void *db, void *txn, NSS_DBC **dbcp);
/* This is the wrapper we put around the `DB' structures to provide a
uniform interface to the higher-level functions. */
int (*close) (void *, uint32_t);
int (*cursor) (void *, void *, NSS_DBC **);
int (*fd) (void *, int *);
- int (*get) (void *, void *, void *, void *, uint32_t);
- int (*put) (void *, void *, void *, void *, uint32_t);
+ int (*get) (void *, void *, DBT *, DBT *, uint32_t);
+ int (*put) (void *, void *, DBT *, DBT *, uint32_t);
} NSS_DB;
+/* Open the database stored in FILE. If succesful, store the database
+ handle in *DBP and return NSS_STATUS_SUCCESS. On failure, return
+ the appropriate lookup status. */
+extern enum nss_status internal_setent (const char *file, NSS_DB **dbp);
-/* The `DBT' type is the same in all versions we support. */
-typedef struct {
- void *data;
- uint32_t size;
- uint32_t ulen;
- uint32_t dlen;
- uint32_t doff;
- uint32_t flags;
-} DBT;
-
+/* Close the database *DBP. */
+extern void internal_endent (NSS_DB **dbp);
-/* Private routines to nss_db.
- You must have included nsswitch.h and db.h before this file. */
+/* Dynamically load the Berkeley DB library. Return zero if
+ successful, non-zero if no suitable version of the library could be
+ loaded. */
+extern enum nss_status load_db (void);
-extern enum nss_status internal_setent (const char *file, NSS_DB **dbp);
-extern void internal_endent (NSS_DB **dbp);
-extern int db_cursor (void *db, void *txn, NSS_DBC **dbcp);
-extern int load_db (void);
+/* Open the database in FNAME, for access specified by FLAGS. If
+ opening the database causes the file FNAME to be created, it is
+ created with MODE. If succesful, store the database handle in *DBP
+ and return NSS_STATUS_SUCCESS. On failure, return the appropriate
+ lookup status. */
extern int dbopen (const char *fname, int oper, int mode, NSS_DB **dbp);
-
#endif /* nss_db.h */
projects / thirdparty / glibc.git / commitdiff
