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glibc  2.9
Enumerations | Functions | Variables
db-open.c File Reference
#include <errno.h>
#include <fcntl.h>
#include <dlfcn.h>
#include <stdlib.h>
#include <string.h>
#include <bits/libc-lock.h>
#include "dummy-db.h"
#include "nss_db.h"

Go to the source code of this file.

Enumerations

enum  { nodb, db24, db27, db30 }

Functions

 __libc_lock_define_initialized (static, lock)
static int set_cloexec_flag (int fd)
static void __attribute__ ((destructor))
enum nss_status internal_setent (const char *file, NSS_DB **dbp)
void internal_endent (NSS_DB **dbp)
int db_cursor (void *db, void *txn, NSS_DBC **dbcp)
int dbopen (const char *fname, int oper, int mode, NSS_DB **dbp)

Variables

static void * libdb_handle
enum { ... }  libdb_version
static int(* libdb_db_open )(const char *, int, uint32_t, int, void *, void *, void **)
static int(* libdb_db_create )(void *, void *, uint32_t)
int db_first
int db_next
int db_nooverwrite
int db_truncate
int db_rdonly
int db_keyexist
int db_notfound

Enumeration Type Documentation

anonymous enum
Enumerator:
nodb 
db24 
db27 
db30 

Definition at line 47 of file db-open.c.


Function Documentation

static void __attribute__ ( (destructor)  ) [static]

Definition at line 193 of file db-open.c.

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__libc_lock_define_initialized ( static  ,
lock   
)

Definition at line 73 of file db-open.c.

{
  static const char *libnames[] = { "libdb.so.3", "libdb-3.0.so" };
  int x;

  for (x = 0; x < sizeof (libnames) / sizeof (libnames[0]); ++x)
    {
      libdb_handle = dlopen (libnames[x], RTLD_LAZY);
      if (libdb_handle == NULL)
       continue;

      /* 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.  */
       libdb_db_open = dlsym (libdb_handle, "db_open");

      if (libdb_db_open != NULL || libdb_db_create != NULL)
       {
         /* Alright, we got a library.  Now find out which version it is.  */
         const char *(*db_version) (int *, int *, int *);

         db_version = dlsym (libdb_handle, "db_version");
         if (db_version != NULL)
           {
             /* Call the function and get the information.  */
             int major, minor, subminor;

             DL_CALL_FCT (db_version, (&major, &minor, &subminor));
             switch (major)
              {
              case 2:
                /* Sanity check: Do we have db_open?  */
                if (libdb_db_open != NULL)
                  {
                    if (minor < 6 || (minor == 6 && subminor < 4))
                     {
                       libdb_version = db24;
                       db_first = DB24_FIRST;
                       db_next = DB24_NEXT;
                       db_nooverwrite = DB24_NOOVERWRITE;
                       db_truncate = DB24_TRUNCATE;
                     }
                    else
                     {
                       libdb_version = db27;
                       db_first = DB27_FIRST;
                       db_next = DB27_NEXT;
                       db_nooverwrite = DB27_NOOVERWRITE;
                       db_truncate = DB27_TRUNCATE;
                     }
                    db_keyexist = DB2x_KEYEXIST;
                    db_notfound = DB2x_NOTFOUND;
                    db_rdonly = DB2x_RDONLY;
                  }
                break;

              case 3:
                /* Sanity check: Do we have db_create?  */
                if (libdb_db_create != NULL)
                  {
                    libdb_version = db30;
                    db_first = DB30_FIRST;
                    db_next = DB30_NEXT;
                    db_keyexist = DB30_KEYEXIST;
                    db_notfound = DB30_NOTFOUND;
                    db_rdonly = DB30_RDONLY;
                  }
                break;

              default:
                break;
              }
           }

         if (libdb_version != nodb)
           return NSS_STATUS_SUCCESS;

         /* Clear variables.  */
         libdb_db_open = NULL;
         libdb_db_create = NULL;
       }

      dlclose (libdb_handle);
    }

  (void) dlerror ();
  return NSS_STATUS_UNAVAIL;
}

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int db_cursor ( void *  db,
void *  txn,
NSS_DBC **  dbcp 
)

Definition at line 250 of file db-open.c.

{
  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, &dbc->cursor);

      if (ret == 0)
       dbc->c_get = ((struct dbc24 *) dbc->cursor)->c_get;
      break;

    case db27:
      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, &dbc->cursor, 0);

      if (ret == 0)
       dbc->c_get = ((struct dbc30 *) dbc->cursor)->c_get;
      break;

    default:
      abort ();
    }

  if (ret != 0)
    {
      free (dbc);
      return ret;
    }

  *dbcp = dbc;

  return 0;
}

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int dbopen ( const char *  fname,
int  oper,
int  mode,
NSS_DB **  dbp 
)

Definition at line 304 of file db-open.c.

{
  int err;
  int fd;
  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, &db->db));
      if (err != 0)
       goto fail;

      if (libdb_version)
       {
         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, (db->db, NULL, 0));
      if (err != 0)
       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)
       goto fail;
      break;

    default:
      abort ();
    }

  /* 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;

  *dbp = db;

  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);
    }

  /* Make sure `errno' is set.  */
  if (err)
    __set_errno (err);

  return err == EAGAIN ? NSS_STATUS_TRYAGAIN : NSS_STATUS_UNAVAIL;
}

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void internal_endent ( NSS_DB **  dbp)

Definition at line 235 of file db-open.c.

{
  NSS_DB *db = *dbp;

  if (db != NULL)
    {
      DL_CALL_FCT (db->close, (db->db, 0));
      *dbp = NULL;
    }
}

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enum nss_status internal_setent ( const char *  file,
NSS_DB **  dbp 
)

Definition at line 209 of file db-open.c.

{
  enum nss_status status = NSS_STATUS_SUCCESS;

  if (*dbp == NULL)
    {
      if (libdb_db_open == NULL && libdb_db_create == NULL)
       {
         __libc_lock_lock (lock);

         if (libdb_db_open == NULL && libdb_db_create == NULL)
           status = load_db ();

         __libc_lock_unlock (lock);
       }

      if (status == NSS_STATUS_SUCCESS)
       status = dbopen (file, db_rdonly, 0, dbp);
    }

  return status;
}

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static int set_cloexec_flag ( int  fd) [static]

Definition at line 180 of file db-open.c.

{
  int oldflags = fcntl (fd, F_GETFD, 0);

  if (oldflags < 0)
    return oldflags;

  oldflags |= FD_CLOEXEC;

  return fcntl (fd, F_SETFD, oldflags);
}

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Variable Documentation

Definition at line 63 of file db-open.c.

Definition at line 69 of file db-open.c.

Definition at line 64 of file db-open.c.

Definition at line 65 of file db-open.c.

Definition at line 70 of file db-open.c.

Definition at line 67 of file db-open.c.

Definition at line 66 of file db-open.c.

int(* libdb_db_create)(void *, void *, uint32_t) [static]

Definition at line 59 of file db-open.c.

int(* libdb_db_open)(const char *, int, uint32_t, int, void *, void *, void **) [static]

Definition at line 55 of file db-open.c.

void* libdb_handle [static]

Definition at line 44 of file db-open.c.

enum { ... } libdb_version