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Diffstat (limited to '')
-rw-r--r-- | src/global/mkmap_open.c | 313 |
1 files changed, 313 insertions, 0 deletions
diff --git a/src/global/mkmap_open.c b/src/global/mkmap_open.c new file mode 100644 index 0000000..9d15eec --- /dev/null +++ b/src/global/mkmap_open.c @@ -0,0 +1,313 @@ +/*++ +/* NAME +/* mkmap_open 3 +/* SUMMARY +/* create or rewrite database, generic interface +/* SYNOPSIS +/* #include <mkmap.h> +/* +/* typedef struct MKMAP { +/* DICT_OPEN_FN open; /* dict_xx_open() */ +/* DICT *dict; /* dict_xx_open() result */ +/* void (*after_open) (struct MKMAP *); /* may be null */ +/* void (*after_close) (struct MKMAP *); /* may be null */ +/* int multi_writer; /* multi-writer safe */ +/* } MKMAP; +/* +/* MKMAP *mkmap_open(type, path, open_flags, dict_flags) +/* char *type; +/* char *path; +/* int open_flags; +/* int dict_flags; +/* +/* void mkmap_append(mkmap, key, value, lineno) +/* MKMAP *mkmap; +/* char *key; +/* char *value; +/* int lineno; +/* +/* void mkmap_close(mkmap) +/* MKMAP *mkmap; +/* +/* typedef MKMAP *(*MKMAP_OPEN_FN) (const char *); +/* typedef MKMAP_OPEN_FN *(*MKMAP_OPEN_EXTEND_FN) (const char *); +/* +/* void mkmap_open_register(type, open_fn) +/* const char *type; +/* MKMAP_OPEN_FN open_fn; +/* +/* MKMAP_OPEN_EXTEND_FN mkmap_open_extend(call_back) +/* MKMAP_OPEN_EXTEND_FN call_back; +/* DESCRIPTION +/* This module implements support for creating Postfix databases. +/* It is a dict(3) wrapper that adds global locking to dict-level +/* routines where appropriate. +/* +/* mkmap_open() creates or truncates the named database, after +/* appending the appropriate suffixes to the specified filename. +/* Before the database is updated, it is locked for exclusive +/* access, and signal delivery is suspended. +/* See dict(3) for a description of \fBopen_flags\fR and +/* \fBdict_flags\fR. All errors are fatal. +/* +/* mkmap_append() appends the named (key, value) pair to the +/* database. Update errors are fatal; duplicate keys are ignored +/* (but a warning is issued). +/* \fBlineno\fR is used for diagnostics. +/* +/* mkmap_close() closes the database, releases any locks, +/* and resumes signal delivery. All errors are fatal. +/* +/* mkmap_open_register() adds support for a new database type. +/* +/* mkmap_open_extend() registers a call-back function that looks +/* up the mkmap open() function for a database type that is not +/* registered, or null in case of error. The result value is the +/* last previously-registered call-back or null. A mkmap open() +/* function is cached after it is looked up through this extension +/* mechanism. +/* SEE ALSO +/* sigdelay(3) suspend/resume signal delivery +/* LICENSE +/* .ad +/* .fi +/* The Secure Mailer license must be distributed with this software. +/* AUTHOR(S) +/* Wietse Venema +/* IBM T.J. Watson Research +/* P.O. Box 704 +/* Yorktown Heights, NY 10598, USA +/*--*/ + +/* System library. */ + +#include <sys_defs.h> +#include <unistd.h> +#include <string.h> + +/* Utility library. */ + +#include <msg.h> +#include <htable.h> +#include <dict.h> +#include <dict_db.h> +#include <dict_cdb.h> +#include <dict_dbm.h> +#include <dict_lmdb.h> +#include <dict_sdbm.h> +#include <dict_proxy.h> +#include <dict_fail.h> +#include <sigdelay.h> +#include <mymalloc.h> +#include <stringops.h> + +/* Global library. */ + +#include "mkmap.h" + + /* + * Information about available database types. Here, we list only those map + * types that support "bulk create" operations. + * + * We use a different table (in dict_open.c and mail_dict.c) when querying maps + * or when making incremental updates. + */ +typedef struct { + const char *type; + MKMAP_OPEN_FN before_open; +} MKMAP_OPEN_INFO; + +static const MKMAP_OPEN_INFO mkmap_open_info[] = { +#ifndef USE_DYNAMIC_MAPS +#ifdef HAS_CDB + DICT_TYPE_CDB, mkmap_cdb_open, +#endif +#ifdef HAS_SDBM + DICT_TYPE_SDBM, mkmap_sdbm_open, +#endif +#ifdef HAS_LMDB + DICT_TYPE_LMDB, mkmap_lmdb_open, +#endif +#endif /* !USE_DYNAMIC_MAPS */ +#ifdef HAS_DBM + DICT_TYPE_DBM, mkmap_dbm_open, +#endif +#ifdef HAS_DB + DICT_TYPE_HASH, mkmap_hash_open, + DICT_TYPE_BTREE, mkmap_btree_open, +#endif + DICT_TYPE_FAIL, mkmap_fail_open, + 0, +}; + +static HTABLE *mkmap_open_hash; + +static MKMAP_OPEN_EXTEND_FN mkmap_open_extend_hook = 0; + +/* mkmap_open_init - one-off initialization */ + +static void mkmap_open_init(void) +{ + static const char myname[] = "mkmap_open_init"; + const MKMAP_OPEN_INFO *mp; + + if (mkmap_open_hash != 0) + msg_panic("%s: multiple initialization", myname); + mkmap_open_hash = htable_create(10); + + for (mp = mkmap_open_info; mp->type; mp++) + htable_enter(mkmap_open_hash, mp->type, (void *) mp); +} + +/* mkmap_open_register - register dictionary type */ + +void mkmap_open_register(const char *type, MKMAP_OPEN_FN open_fn) +{ + static const char myname[] = "mkmap_open_register"; + MKMAP_OPEN_INFO *mp; + HTABLE_INFO *ht; + + if (mkmap_open_hash == 0) + mkmap_open_init(); + if (htable_find(mkmap_open_hash, type)) + msg_panic("%s: database type exists: %s", myname, type); + mp = (MKMAP_OPEN_INFO *) mymalloc(sizeof(*mp)); + mp->before_open = open_fn; + ht = htable_enter(mkmap_open_hash, type, (void *) mp); + mp->type = ht->key; +} + +/* mkmap_open_extend - register alternate lookup function */ + +MKMAP_OPEN_EXTEND_FN mkmap_open_extend(MKMAP_OPEN_EXTEND_FN new_cb) +{ + MKMAP_OPEN_EXTEND_FN old_cb; + + old_cb = mkmap_open_extend_hook; + mkmap_open_extend_hook = new_cb; + return (old_cb); +} + +/* mkmap_append - append entry to map */ + +#undef mkmap_append + +void mkmap_append(MKMAP *mkmap, const char *key, const char *value) +{ + DICT *dict = mkmap->dict; + + if (dict_put(dict, key, value) != 0 && dict->error != 0) + msg_fatal("%s:%s: update failed", dict->type, dict->name); +} + +/* mkmap_close - close database */ + +void mkmap_close(MKMAP *mkmap) +{ + + /* + * Close the database. + */ + dict_close(mkmap->dict); + + /* + * Do whatever special processing is needed after closing the database, + * such as releasing a global exclusive lock on the database file. + * Individual Postfix dict modules implement locking only for individual + * record operations, because most Postfix applications don't need global + * exclusive locks. + */ + if (mkmap->after_close) + mkmap->after_close(mkmap); + + /* + * Resume signal delivery. + */ + if (mkmap->multi_writer == 0) + sigresume(); + + /* + * Cleanup. + */ + myfree((void *) mkmap); +} + +/* mkmap_open - create or truncate database */ + +MKMAP *mkmap_open(const char *type, const char *path, + int open_flags, int dict_flags) +{ + MKMAP *mkmap; + const MKMAP_OPEN_INFO *mp; + MKMAP_OPEN_FN open_fn; + + /* + * Find out what map type to use. + */ + if (mkmap_open_hash == 0) + mkmap_open_init(); + if ((mp = (MKMAP_OPEN_INFO *) htable_find(mkmap_open_hash, type)) == 0) { + if (mkmap_open_extend_hook != 0 && + (open_fn = mkmap_open_extend_hook(type)) != 0) { + mkmap_open_register(type, open_fn); + mp = (MKMAP_OPEN_INFO *) htable_find(mkmap_open_hash, type); + } + if (mp == 0) + msg_fatal("unsupported map type for this operation: %s", type); + } + if (msg_verbose) + msg_info("open %s %s", type, path); + + /* + * Do whatever before-open initialization is needed, such as acquiring a + * global exclusive lock on an existing database file. Individual Postfix + * dict modules implement locking only for individual record operations, + * because most Postfix applications don't need global exclusive locks. + */ + mkmap = mp->before_open(path); + + /* + * Delay signal delivery, so that we won't leave the database in an + * inconsistent state if we can avoid it. + */ + sigdelay(); + + /* + * Truncate the database upon open, and update it. Read-write mode is + * needed because the underlying routines read as well as write. We + * explicitly clobber lock_fd to trigger a fatal error when a map wants + * to unlock the database after individual transactions: that would + * result in race condition problems. We clobbber stat_fd as well, + * because that, too, is used only for individual-transaction clients. + */ + mkmap->dict = mkmap->open(path, open_flags, dict_flags); + mkmap->dict->lock_fd = -1; /* XXX just in case */ + mkmap->dict->stat_fd = -1; /* XXX just in case */ + mkmap->dict->flags |= DICT_FLAG_DUP_WARN; + mkmap->multi_writer = (mkmap->dict->flags & DICT_FLAG_MULTI_WRITER); + + /* + * Do whatever post-open initialization is needed, such as acquiring a + * global exclusive lock on a database file that did not exist. + * Individual Postfix dict modules implement locking only for individual + * record operations, because most Postfix applications don't need global + * exclusive locks. + */ + if (mkmap->after_open) + mkmap->after_open(mkmap); + + /* + * Wrap the dictionary for UTF-8 syntax checks and casefolding. + */ + if ((mkmap->dict->flags & DICT_FLAG_UTF8_ACTIVE) == 0 + && DICT_NEED_UTF8_ACTIVATION(util_utf8_enable, dict_flags)) + mkmap->dict = dict_utf8_activate(mkmap->dict); + + /* + * Resume signal delivery if multi-writer safe. + */ + if (mkmap->multi_writer) + sigresume(); + + return (mkmap); +} |