diff options
Diffstat (limited to 'src/gdbmreorg.c')
-rw-r--r-- | src/gdbmreorg.c | 218 |
1 files changed, 218 insertions, 0 deletions
diff --git a/src/gdbmreorg.c b/src/gdbmreorg.c new file mode 100644 index 0000000..7e554cb --- /dev/null +++ b/src/gdbmreorg.c @@ -0,0 +1,218 @@ +/* gdbmreorg.c - Reorganize the database file. */ + +/* This file is part of GDBM, the GNU data base manager. + Copyright (C) 1990, 1991, 1993, 2007, 2011, 2013 Free Software Foundation, + Inc. + + GDBM is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 3, or (at your option) + any later version. + + GDBM 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 General Public License for more details. + + You should have received a copy of the GNU General Public License + along with GDBM. If not, see <http://www.gnu.org/licenses/>. */ + +/* Include system configuration before all else. */ +#include "autoconf.h" + +#include "gdbmdefs.h" + +#if !HAVE_RENAME + +/* Rename takes OLD_NAME and renames it as NEW_NAME. If it can not rename + the file a non-zero value is returned. OLD_NAME is guaranteed to + remain if it can't be renamed. It assumes NEW_NAME always exists (due + to being used in gdbm). */ + +static int +_gdbm_rename (char *old_name, char *new_name) +{ + if (unlink (new_name) != 0) + return -1; + + if (link (old_name, new_name) != 0) + return -1; + + unlink (old_name); + return 0; + +} + +# define rename _gdbm_rename +#endif + + + +/* Reorganize the database. This requires creating a new file and inserting + all the elements in the old file DBF into the new file. The new file + is then renamed to the same name as the old file and DBF is updated to + contain all the correct information about the new file. If an error + is detected, the return value is negative. The value zero is returned + after a successful reorganization. */ + +int +gdbm_reorganize (GDBM_FILE dbf) +{ + GDBM_FILE new_dbf; /* The new file. */ + char *new_name; /* A temporary name. */ + int len; /* Used in new_name construction. */ + datum key, nextkey, data; /* For the sequential sweep. */ + struct stat fileinfo; /* Information about the file. */ + int index; /* Use in moving the bucket cache. */ + + + /* Readers can not reorganize! */ + if (dbf->read_write == GDBM_READER) + { + gdbm_errno = GDBM_READER_CANT_REORGANIZE; + return -1; + } + + /* Get the mode for the old file */ + if (fstat (dbf->desc, &fileinfo)) + { + gdbm_errno = GDBM_FILE_STAT_ERROR; + return -1; + } + + /* Initialize the gdbm_errno variable. */ + gdbm_errno = GDBM_NO_ERROR; + + /* Construct new name for temporary file. */ + len = strlen (dbf->name); + new_name = (char *) malloc (len + 3); + if (new_name == NULL) + { + gdbm_errno = GDBM_MALLOC_ERROR; + return -1; + } + strcpy (&new_name[0], dbf->name); + new_name[len+2] = 0; + new_name[len+1] = '#'; + while ( (len > 0) && new_name[len-1] != '/') + { + new_name[len] = new_name[len-1]; + len -= 1; + } + new_name[len] = '#'; + + /* Open the new database. */ + new_dbf = gdbm_open (new_name, dbf->header->block_size, + GDBM_WRCREAT | (dbf->cloexec ? GDBM_CLOEXEC : 0), + fileinfo.st_mode, dbf->fatal_err); + + if (new_dbf == NULL) + { + free (new_name); + gdbm_errno = GDBM_REORGANIZE_FAILED; + return -1; + } + + + /* For each item in the old database, add an entry in the new. */ + key = gdbm_firstkey (dbf); + + while (key.dptr != NULL) + { + data = gdbm_fetch (dbf, key); + if (data.dptr != NULL) + { + /* Add the data to the new file. */ + if (gdbm_store (new_dbf, key, data, GDBM_INSERT) != 0) + { + gdbm_close (new_dbf); + gdbm_errno = GDBM_REORGANIZE_FAILED; + unlink (new_name); + free (new_name); + return -1; + } + } + else + { + /* ERROR! Abort and don't finish reorganize. */ + gdbm_close (new_dbf); + gdbm_errno = GDBM_REORGANIZE_FAILED; + unlink (new_name); + free (new_name); + return -1; + } + nextkey = gdbm_nextkey (dbf, key); + free (key.dptr); + free (data.dptr); + key = nextkey; + } + + /* Write everything. */ + _gdbm_end_update (new_dbf); + gdbm_sync (new_dbf); + +#if HAVE_MMAP + _gdbm_mapped_unmap (dbf); +#endif + + /* Move the new file to old name. */ + + if (rename (new_name, dbf->name) != 0) + { + gdbm_errno = GDBM_REORGANIZE_FAILED; + gdbm_close (new_dbf); + free (new_name); + return -1; + } + + /* Fix up DBF to have the correct information for the new file. */ + if (dbf->file_locking) + { + _gdbm_unlock_file (dbf); + } + close (dbf->desc); + free (dbf->header); + free (dbf->dir); + + if (dbf->bucket_cache != NULL) { + for (index = 0; index < dbf->cache_size; index++) { + if (dbf->bucket_cache[index].ca_bucket != NULL) + free (dbf->bucket_cache[index].ca_bucket); + if (dbf->bucket_cache[index].ca_data.dptr != NULL) + free (dbf->bucket_cache[index].ca_data.dptr); + } + free (dbf->bucket_cache); + } + + dbf->desc = new_dbf->desc; + dbf->header = new_dbf->header; + dbf->dir = new_dbf->dir; + dbf->bucket = new_dbf->bucket; + dbf->bucket_dir = new_dbf->bucket_dir; + dbf->last_read = new_dbf->last_read; + dbf->bucket_cache = new_dbf->bucket_cache; + dbf->cache_size = new_dbf->cache_size; + dbf->header_changed = new_dbf->header_changed; + dbf->directory_changed = new_dbf->directory_changed; + dbf->bucket_changed = new_dbf->bucket_changed; + dbf->second_changed = new_dbf->second_changed; + +#if HAVE_MMAP + /* Re-initialize mapping if required */ + if (dbf->memory_mapping) + _gdbm_mapped_init (dbf); +#endif + + free (new_dbf->name); + free (new_dbf); + free (new_name); + + /* Make sure the new database is all on disk. */ + __fsync (dbf); + + /* Force the right stuff for a correct bucket cache. */ + dbf->cache_entry = &dbf->bucket_cache[0]; + _gdbm_get_bucket (dbf, 0); + + return 0; +} |