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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:46:30 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:46:30 +0000
commitb5896ba9f6047e7031e2bdee0622d543e11a6734 (patch)
treefd7b460593a2fee1be579bec5697e6d887ea3421 /src/util/dict_cache.c
parentInitial commit. (diff)
downloadpostfix-b5896ba9f6047e7031e2bdee0622d543e11a6734.tar.xz
postfix-b5896ba9f6047e7031e2bdee0622d543e11a6734.zip
Adding upstream version 3.4.23.upstream/3.4.23upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/util/dict_cache.c')
-rw-r--r--src/util/dict_cache.c1121
1 files changed, 1121 insertions, 0 deletions
diff --git a/src/util/dict_cache.c b/src/util/dict_cache.c
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--- /dev/null
+++ b/src/util/dict_cache.c
@@ -0,0 +1,1121 @@
+/*++
+/* NAME
+/* dict_cache 3
+/* SUMMARY
+/* External cache manager
+/* SYNOPSIS
+/* #include <dict_cache.h>
+/*
+/* DICT_CACHE *dict_cache_open(dbname, open_flags, dict_flags)
+/* const char *dbname;
+/* int open_flags;
+/* int dict_flags;
+/*
+/* void dict_cache_close(cache)
+/* DICT_CACHE *cache;
+/*
+/* const char *dict_cache_lookup(cache, cache_key)
+/* DICT_CACHE *cache;
+/* const char *cache_key;
+/*
+/* int dict_cache_update(cache, cache_key, cache_val)
+/* DICT_CACHE *cache;
+/* const char *cache_key;
+/* const char *cache_val;
+/*
+/* int dict_cache_delete(cache, cache_key)
+/* DICT_CACHE *cache;
+/* const char *cache_key;
+/*
+/* int dict_cache_sequence(cache, first_next, cache_key, cache_val)
+/* DICT_CACHE *cache;
+/* int first_next;
+/* const char **cache_key;
+/* const char **cache_val;
+/* AUXILIARY FUNCTIONS
+/* void dict_cache_control(cache, name, value, ...)
+/* DICT_CACHE *cache;
+/* int name;
+/*
+/* typedef int (*DICT_CACHE_VALIDATOR_FN) (const char *cache_key,
+/* const char *cache_val, void *context);
+/*
+/* const char *dict_cache_name(cache)
+/* DICT_CACHE *cache;
+/* DESCRIPTION
+/* This module maintains external cache files with support
+/* for expiration. The underlying table must implement the
+/* "lookup", "update", "delete" and "sequence" operations.
+/*
+/* Although this API is similar to the one documented in
+/* dict_open(3), there are subtle differences in the interaction
+/* between the iterators that access all cache elements, and
+/* other operations that access individual cache elements.
+/*
+/* In particular, when a "sequence" or "cleanup" operation is
+/* in progress the cache intercepts requests to delete the
+/* "current" entry, as this would cause some databases to
+/* mis-behave. Instead, the cache implements a "delete behind"
+/* strategy, and deletes such an entry after the "sequence"
+/* or "cleanup" operation moves on to the next cache element.
+/* The "delete behind" strategy also affects the cache lookup
+/* and update operations as detailed below.
+/*
+/* dict_cache_open() is a wrapper around the dict_open()
+/* function. It opens the specified cache and returns a handle
+/* that must be used for subsequent access. This function does
+/* not return in case of error.
+/*
+/* dict_cache_close() closes the specified cache and releases
+/* memory that was allocated by dict_cache_open(), and terminates
+/* any thread that was started with dict_cache_control().
+/*
+/* dict_cache_lookup() looks up the specified cache entry.
+/* The result value is a null pointer when the cache entry was
+/* not found, or when the entry is scheduled for "delete
+/* behind".
+/*
+/* dict_cache_update() updates the specified cache entry. If
+/* the entry is scheduled for "delete behind", the delete
+/* operation is canceled (because of this, the cache must be
+/* opened with DICT_FLAG_DUP_REPLACE). This function does not
+/* return in case of error.
+/*
+/* dict_cache_delete() removes the specified cache entry. If
+/* this is the "current" entry of a "sequence" operation, the
+/* entry is scheduled for "delete behind". The result value
+/* is zero when the entry was found.
+/*
+/* dict_cache_sequence() iterates over the specified cache and
+/* returns each entry in an implementation-defined order. The
+/* result value is zero when a cache entry was found.
+/*
+/* Important: programs must not use both dict_cache_sequence()
+/* and the built-in cache cleanup feature.
+/*
+/* dict_cache_control() provides control over the built-in
+/* cache cleanup feature and logging. The arguments are a list
+/* of macros with zero or more arguments, terminated with
+/* CA_DICT_CACHE_CTL_END which has none. The following lists
+/* the macros and corresponding argument types.
+/* .IP "CA_DICT_CACHE_CTL_FLAGS(int flags)"
+/* The arguments to this command are the bit-wise OR of zero
+/* or more of the following:
+/* .RS
+/* .IP CA_DICT_CACHE_CTL_FLAG_VERBOSE
+/* Enable verbose logging of cache activity.
+/* .IP CA_DICT_CACHE_CTL_FLAG_EXP_SUMMARY
+/* Log cache statistics after each cache cleanup run.
+/* .RE
+/* .IP "CA_DICT_CACHE_CTL_INTERVAL(int interval)"
+/* The interval between cache cleanup runs. Specify a null
+/* validator or interval to stop cache cleanup.
+/* .IP "CA_DICT_CACHE_CTL_VALIDATOR(DICT_CACHE_VALIDATOR_FN validator)"
+/* An application call-back routine that returns non-zero when
+/* a cache entry should be kept. The call-back function should
+/* not make changes to the cache. Specify a null validator or
+/* interval to stop cache cleanup.
+/* .IP "CA_DICT_CACHE_CTL_CONTEXT(void *context)"
+/* Application context that is passed to the validator function.
+/* .RE
+/* .PP
+/* dict_cache_name() returns the name of the specified cache.
+/*
+/* Arguments:
+/* .IP "dbname, open_flags, dict_flags"
+/* These are passed unchanged to dict_open(). The cache must
+/* be opened with DICT_FLAG_DUP_REPLACE.
+/* .IP cache
+/* Cache handle created with dict_cache_open().
+/* .IP cache_key
+/* Cache lookup key.
+/* .IP cache_val
+/* Information that is stored under a cache lookup key.
+/* .IP first_next
+/* One of DICT_SEQ_FUN_FIRST (first cache element) or
+/* DICT_SEQ_FUN_NEXT (next cache element).
+/* .sp
+/* Note: there is no "stop" request. To ensure that the "delete
+/* behind" strategy does not interfere with database access,
+/* allow dict_cache_sequence() to run to completion.
+/* .IP table
+/* A bare dictonary handle.
+/* DIAGNOSTICS
+/* When a request is satisfied, the lookup routine returns
+/* non-null, and the update, delete and sequence routines
+/* return zero. The cache->error value is zero when a request
+/* could not be satisfied because an item did not exist (delete,
+/* sequence) or if it could not be updated. The cache->error
+/* value is non-zero only when a request could not be satisfied,
+/* and the cause was a database error.
+/*
+/* Cache access errors are logged with a warning message. To
+/* avoid spamming the log, each type of operation logs no more
+/* than one cache access error per second, per cache. Specify
+/* the DICT_CACHE_FLAG_VERBOSE flag (see above) to log all
+/* warnings.
+/* BUGS
+/* There should be a way to suspend automatic program suicide
+/* until a cache cleanup run is completed. Some entries may
+/* never be removed when the process max_idle time is less
+/* than the time needed to make a full pass over the cache.
+/*
+/* The delete-behind strategy assumes that all updates are
+/* made by a single process. Otherwise, delete-behind may
+/* remove an entry that was updated after it was scheduled for
+/* deletion.
+/* LICENSE
+/* .ad
+/* .fi
+/* The Secure Mailer license must be distributed with this software.
+/* HISTORY
+/* .ad
+/* .fi
+/* A predecessor of this code was written first for the Postfix
+/* tlsmgr(8) daemon.
+/* 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 <string.h>
+#include <stdlib.h>
+
+/* Utility library. */
+
+#include <msg.h>
+#include <dict.h>
+#include <mymalloc.h>
+#include <events.h>
+#include <dict_cache.h>
+
+/* Application-specific. */
+
+ /*
+ * XXX Deleting entries while enumerating a map can he tricky. Some map
+ * types have a concept of cursor and support a "delete the current element"
+ * operation. Some map types without cursors don't behave well when the
+ * current first/next entry is deleted (example: with Berkeley DB < 2, the
+ * "next" operation produces garbage). To avoid trouble, we delete an entry
+ * after advancing the current first/next position beyond it; we use the
+ * same strategy with application requests to delete the current entry.
+ */
+
+ /*
+ * Opaque data structure. Use dict_cache_name() to access the name of the
+ * underlying database.
+ */
+struct DICT_CACHE {
+ char *name; /* full name including proxy: */
+ int cache_flags; /* see below */
+ int user_flags; /* logging */
+ DICT *db; /* database handle */
+ int error; /* last operation only */
+
+ /* Delete-behind support. */
+ char *saved_curr_key; /* "current" cache lookup key */
+ char *saved_curr_val; /* "current" cache lookup result */
+
+ /* Cleanup support. */
+ int exp_interval; /* time between cleanup runs */
+ DICT_CACHE_VALIDATOR_FN exp_validator; /* expiration call-back */
+ void *exp_context; /* call-back context */
+ int retained; /* entries retained in cleanup run */
+ int dropped; /* entries removed in cleanup run */
+
+ /* Rate-limited logging support. */
+ int log_delay;
+ time_t upd_log_stamp; /* last update warning */
+ time_t get_log_stamp; /* last lookup warning */
+ time_t del_log_stamp; /* last delete warning */
+ time_t seq_log_stamp; /* last sequence warning */
+};
+
+#define DC_FLAG_DEL_SAVED_CURRENT_KEY (1<<0) /* delete-behind is scheduled */
+
+ /*
+ * Don't log cache access errors more than once per second.
+ */
+#define DC_DEF_LOG_DELAY 1
+
+ /*
+ * Macros to make obscure code more readable.
+ */
+#define DC_SCHEDULE_FOR_DELETE_BEHIND(cp) \
+ ((cp)->cache_flags |= DC_FLAG_DEL_SAVED_CURRENT_KEY)
+
+#define DC_MATCH_SAVED_CURRENT_KEY(cp, cache_key) \
+ ((cp)->saved_curr_key && strcmp((cp)->saved_curr_key, (cache_key)) == 0)
+
+#define DC_IS_SCHEDULED_FOR_DELETE_BEHIND(cp) \
+ (/* NOT: (cp)->saved_curr_key && */ \
+ ((cp)->cache_flags & DC_FLAG_DEL_SAVED_CURRENT_KEY) != 0)
+
+#define DC_CANCEL_DELETE_BEHIND(cp) \
+ ((cp)->cache_flags &= ~DC_FLAG_DEL_SAVED_CURRENT_KEY)
+
+ /*
+ * Special key to store the time of the last cache cleanup run completion.
+ */
+#define DC_LAST_CACHE_CLEANUP_COMPLETED "_LAST_CACHE_CLEANUP_COMPLETED_"
+
+/* dict_cache_lookup - load entry from cache */
+
+const char *dict_cache_lookup(DICT_CACHE *cp, const char *cache_key)
+{
+ const char *myname = "dict_cache_lookup";
+ const char *cache_val;
+ DICT *db = cp->db;
+
+ /*
+ * Search for the cache entry. Don't return an entry that is scheduled
+ * for delete-behind.
+ */
+ if (DC_IS_SCHEDULED_FOR_DELETE_BEHIND(cp)
+ && DC_MATCH_SAVED_CURRENT_KEY(cp, cache_key)) {
+ if (cp->user_flags & DICT_CACHE_FLAG_VERBOSE)
+ msg_info("%s: key=%s (pretend not found - scheduled for deletion)",
+ myname, cache_key);
+ DICT_ERR_VAL_RETURN(cp, DICT_ERR_NONE, (char *) 0);
+ } else {
+ cache_val = dict_get(db, cache_key);
+ if (cache_val == 0 && db->error != 0)
+ msg_rate_delay(&cp->get_log_stamp, cp->log_delay, msg_warn,
+ "%s: cache lookup for '%s' failed due to error",
+ cp->name, cache_key);
+ if (cp->user_flags & DICT_CACHE_FLAG_VERBOSE)
+ msg_info("%s: key=%s value=%s", myname, cache_key,
+ cache_val ? cache_val : db->error ?
+ "error" : "(not found)");
+ DICT_ERR_VAL_RETURN(cp, db->error, cache_val);
+ }
+}
+
+/* dict_cache_update - save entry to cache */
+
+int dict_cache_update(DICT_CACHE *cp, const char *cache_key,
+ const char *cache_val)
+{
+ const char *myname = "dict_cache_update";
+ DICT *db = cp->db;
+ int put_res;
+
+ /*
+ * Store the cache entry and cancel the delete-behind operation.
+ */
+ if (DC_IS_SCHEDULED_FOR_DELETE_BEHIND(cp)
+ && DC_MATCH_SAVED_CURRENT_KEY(cp, cache_key)) {
+ if (cp->user_flags & DICT_CACHE_FLAG_VERBOSE)
+ msg_info("%s: cancel delete-behind for key=%s", myname, cache_key);
+ DC_CANCEL_DELETE_BEHIND(cp);
+ }
+ if (cp->user_flags & DICT_CACHE_FLAG_VERBOSE)
+ msg_info("%s: key=%s value=%s", myname, cache_key, cache_val);
+ put_res = dict_put(db, cache_key, cache_val);
+ if (put_res != 0)
+ msg_rate_delay(&cp->upd_log_stamp, cp->log_delay, msg_warn,
+ "%s: could not update entry for %s", cp->name, cache_key);
+ DICT_ERR_VAL_RETURN(cp, db->error, put_res);
+}
+
+/* dict_cache_delete - delete entry from cache */
+
+int dict_cache_delete(DICT_CACHE *cp, const char *cache_key)
+{
+ const char *myname = "dict_cache_delete";
+ int del_res;
+ DICT *db = cp->db;
+
+ /*
+ * Delete the entry, unless we would delete the current first/next entry.
+ * In that case, schedule the "current" entry for delete-behind to avoid
+ * mis-behavior by some databases.
+ */
+ if (DC_MATCH_SAVED_CURRENT_KEY(cp, cache_key)) {
+ DC_SCHEDULE_FOR_DELETE_BEHIND(cp);
+ if (cp->user_flags & DICT_CACHE_FLAG_VERBOSE)
+ msg_info("%s: key=%s (current entry - schedule for delete-behind)",
+ myname, cache_key);
+ DICT_ERR_VAL_RETURN(cp, DICT_ERR_NONE, DICT_STAT_SUCCESS);
+ } else {
+ del_res = dict_del(db, cache_key);
+ if (del_res != 0)
+ msg_rate_delay(&cp->del_log_stamp, cp->log_delay, msg_warn,
+ "%s: could not delete entry for %s", cp->name, cache_key);
+ if (cp->user_flags & DICT_CACHE_FLAG_VERBOSE)
+ msg_info("%s: key=%s (%s)", myname, cache_key,
+ del_res == 0 ? "found" :
+ db->error ? "error" : "not found");
+ DICT_ERR_VAL_RETURN(cp, db->error, del_res);
+ }
+}
+
+/* dict_cache_sequence - look up the first/next cache entry */
+
+int dict_cache_sequence(DICT_CACHE *cp, int first_next,
+ const char **cache_key,
+ const char **cache_val)
+{
+ const char *myname = "dict_cache_sequence";
+ int seq_res;
+ const char *raw_cache_key;
+ const char *raw_cache_val;
+ char *previous_curr_key;
+ char *previous_curr_val;
+ DICT *db = cp->db;
+
+ /*
+ * Find the first or next database entry. Hide the record with the cache
+ * cleanup completion time stamp.
+ */
+ seq_res = dict_seq(db, first_next, &raw_cache_key, &raw_cache_val);
+ if (seq_res == 0
+ && strcmp(raw_cache_key, DC_LAST_CACHE_CLEANUP_COMPLETED) == 0)
+ seq_res =
+ dict_seq(db, DICT_SEQ_FUN_NEXT, &raw_cache_key, &raw_cache_val);
+ if (cp->user_flags & DICT_CACHE_FLAG_VERBOSE)
+ msg_info("%s: key=%s value=%s", myname,
+ seq_res == 0 ? raw_cache_key : db->error ?
+ "(error)" : "(not found)",
+ seq_res == 0 ? raw_cache_val : db->error ?
+ "(error)" : "(not found)");
+ if (db->error)
+ msg_rate_delay(&cp->seq_log_stamp, cp->log_delay, msg_warn,
+ "%s: sequence error", cp->name);
+
+ /*
+ * Save the current cache_key and cache_val before they are clobbered by
+ * our own delete operation below. This also prevents surprises when the
+ * application accesses the database after this function returns.
+ *
+ * We also use the saved cache_key to protect the current entry against
+ * application delete requests.
+ */
+ previous_curr_key = cp->saved_curr_key;
+ previous_curr_val = cp->saved_curr_val;
+ if (seq_res == 0) {
+ cp->saved_curr_key = mystrdup(raw_cache_key);
+ cp->saved_curr_val = mystrdup(raw_cache_val);
+ } else {
+ cp->saved_curr_key = 0;
+ cp->saved_curr_val = 0;
+ }
+
+ /*
+ * Delete behind.
+ */
+ if (db->error == 0 && DC_IS_SCHEDULED_FOR_DELETE_BEHIND(cp)) {
+ DC_CANCEL_DELETE_BEHIND(cp);
+ if (cp->user_flags & DICT_CACHE_FLAG_VERBOSE)
+ msg_info("%s: delete-behind key=%s value=%s",
+ myname, previous_curr_key, previous_curr_val);
+ if (dict_del(db, previous_curr_key) != 0)
+ msg_rate_delay(&cp->del_log_stamp, cp->log_delay, msg_warn,
+ "%s: could not delete entry for %s",
+ cp->name, previous_curr_key);
+ }
+
+ /*
+ * Clean up previous iteration key and value.
+ */
+ if (previous_curr_key)
+ myfree(previous_curr_key);
+ if (previous_curr_val)
+ myfree(previous_curr_val);
+
+ /*
+ * Return the result.
+ */
+ *cache_key = (cp)->saved_curr_key;
+ *cache_val = (cp)->saved_curr_val;
+ DICT_ERR_VAL_RETURN(cp, db->error, seq_res);
+}
+
+/* dict_cache_delete_behind_reset - reset "delete behind" state */
+
+static void dict_cache_delete_behind_reset(DICT_CACHE *cp)
+{
+#define FREE_AND_WIPE(s) do { if (s) { myfree(s); (s) = 0; } } while (0)
+
+ DC_CANCEL_DELETE_BEHIND(cp);
+ FREE_AND_WIPE(cp->saved_curr_key);
+ FREE_AND_WIPE(cp->saved_curr_val);
+}
+
+/* dict_cache_clean_stat_log_reset - log and reset cache cleanup statistics */
+
+static void dict_cache_clean_stat_log_reset(DICT_CACHE *cp,
+ const char *full_partial)
+{
+ if (cp->user_flags & DICT_CACHE_FLAG_STATISTICS)
+ msg_info("cache %s %s cleanup: retained=%d dropped=%d entries",
+ cp->name, full_partial, cp->retained, cp->dropped);
+ cp->retained = cp->dropped = 0;
+}
+
+/* dict_cache_clean_event - examine one cache entry */
+
+static void dict_cache_clean_event(int unused_event, void *cache_context)
+{
+ const char *myname = "dict_cache_clean_event";
+ DICT_CACHE *cp = (DICT_CACHE *) cache_context;
+ const char *cache_key;
+ const char *cache_val;
+ int next_interval;
+ VSTRING *stamp_buf;
+ int first_next;
+
+ /*
+ * We interleave cache cleanup with other processing, so that the
+ * application's service remains available, with perhaps increased
+ * latency.
+ */
+
+ /*
+ * Start a new cache cleanup run.
+ */
+ if (cp->saved_curr_key == 0) {
+ cp->retained = cp->dropped = 0;
+ first_next = DICT_SEQ_FUN_FIRST;
+ if (cp->user_flags & DICT_CACHE_FLAG_VERBOSE)
+ msg_info("%s: start %s cache cleanup", myname, cp->name);
+ }
+
+ /*
+ * Continue a cache cleanup run in progress.
+ */
+ else {
+ first_next = DICT_SEQ_FUN_NEXT;
+ }
+
+ /*
+ * Examine one cache entry.
+ */
+ if (dict_cache_sequence(cp, first_next, &cache_key, &cache_val) == 0) {
+ if (cp->exp_validator(cache_key, cache_val, cp->exp_context) == 0) {
+ DC_SCHEDULE_FOR_DELETE_BEHIND(cp);
+ cp->dropped++;
+ if (cp->user_flags & DICT_CACHE_FLAG_VERBOSE)
+ msg_info("%s: drop %s cache entry for %s",
+ myname, cp->name, cache_key);
+ } else {
+ cp->retained++;
+ if (cp->user_flags & DICT_CACHE_FLAG_VERBOSE)
+ msg_info("%s: keep %s cache entry for %s",
+ myname, cp->name, cache_key);
+ }
+ next_interval = 0;
+ }
+
+ /*
+ * Cache cleanup completed. Report vital statistics.
+ */
+ else if (cp->error != 0) {
+ msg_warn("%s: cache cleanup scan terminated due to error", cp->name);
+ dict_cache_clean_stat_log_reset(cp, "partial");
+ next_interval = cp->exp_interval;
+ } else {
+ if (cp->user_flags & DICT_CACHE_FLAG_VERBOSE)
+ msg_info("%s: done %s cache cleanup scan", myname, cp->name);
+ dict_cache_clean_stat_log_reset(cp, "full");
+ stamp_buf = vstring_alloc(100);
+ vstring_sprintf(stamp_buf, "%ld", (long) event_time());
+ dict_put(cp->db, DC_LAST_CACHE_CLEANUP_COMPLETED,
+ vstring_str(stamp_buf));
+ vstring_free(stamp_buf);
+ next_interval = cp->exp_interval;
+ }
+ event_request_timer(dict_cache_clean_event, cache_context, next_interval);
+}
+
+/* dict_cache_control - schedule or stop the cache cleanup thread */
+
+void dict_cache_control(DICT_CACHE *cp,...)
+{
+ const char *myname = "dict_cache_control";
+ const char *last_done;
+ time_t next_interval;
+ int cache_cleanup_is_active = (cp->exp_validator && cp->exp_interval);
+ va_list ap;
+ int name;
+
+ /*
+ * Update the control settings.
+ */
+ va_start(ap, cp);
+ while ((name = va_arg(ap, int)) > 0) {
+ switch (name) {
+ case DICT_CACHE_CTL_END:
+ break;
+ case DICT_CACHE_CTL_FLAGS:
+ cp->user_flags = va_arg(ap, int);
+ cp->log_delay = (cp->user_flags & DICT_CACHE_FLAG_VERBOSE) ?
+ 0 : DC_DEF_LOG_DELAY;
+ break;
+ case DICT_CACHE_CTL_INTERVAL:
+ cp->exp_interval = va_arg(ap, int);
+ if (cp->exp_interval < 0)
+ msg_panic("%s: bad %s cache cleanup interval %d",
+ myname, cp->name, cp->exp_interval);
+ break;
+ case DICT_CACHE_CTL_VALIDATOR:
+ cp->exp_validator = va_arg(ap, DICT_CACHE_VALIDATOR_FN);
+ break;
+ case DICT_CACHE_CTL_CONTEXT:
+ cp->exp_context = va_arg(ap, void *);
+ break;
+ default:
+ msg_panic("%s: bad command: %d", myname, name);
+ }
+ }
+ va_end(ap);
+
+ /*
+ * Schedule the cache cleanup thread.
+ */
+ if (cp->exp_interval && cp->exp_validator) {
+
+ /*
+ * Sanity checks.
+ */
+ if (cache_cleanup_is_active)
+ msg_panic("%s: %s cache cleanup is already scheduled",
+ myname, cp->name);
+
+ /*
+ * The next start time depends on the last completion time.
+ */
+#define NEXT_START(last, delta) ((delta) + (unsigned long) atol(last))
+#define NOW (time((time_t *) 0)) /* NOT: event_time() */
+
+ if ((last_done = dict_get(cp->db, DC_LAST_CACHE_CLEANUP_COMPLETED)) == 0
+ || (next_interval = (NEXT_START(last_done, cp->exp_interval) - NOW)) < 0)
+ next_interval = 0;
+ if (next_interval > cp->exp_interval)
+ next_interval = cp->exp_interval;
+ if ((cp->user_flags & DICT_CACHE_FLAG_VERBOSE) && next_interval > 0)
+ msg_info("%s cache cleanup will start after %ds",
+ cp->name, (int) next_interval);
+ event_request_timer(dict_cache_clean_event, (void *) cp,
+ (int) next_interval);
+ }
+
+ /*
+ * Cancel the cache cleanup thread.
+ */
+ else if (cache_cleanup_is_active) {
+ if (cp->retained || cp->dropped)
+ dict_cache_clean_stat_log_reset(cp, "partial");
+ dict_cache_delete_behind_reset(cp);
+ event_cancel_timer(dict_cache_clean_event, (void *) cp);
+ }
+}
+
+/* dict_cache_open - open cache file */
+
+DICT_CACHE *dict_cache_open(const char *dbname, int open_flags, int dict_flags)
+{
+ DICT_CACHE *cp;
+ DICT *dict;
+
+ /*
+ * Open the database as requested. Don't attempt to second-guess the
+ * application.
+ */
+ dict = dict_open(dbname, open_flags, dict_flags);
+
+ /*
+ * Create the DICT_CACHE object.
+ */
+ cp = (DICT_CACHE *) mymalloc(sizeof(*cp));
+ cp->name = mystrdup(dbname);
+ cp->cache_flags = 0;
+ cp->user_flags = 0;
+ cp->db = dict;
+ cp->saved_curr_key = 0;
+ cp->saved_curr_val = 0;
+ cp->exp_interval = 0;
+ cp->exp_validator = 0;
+ cp->exp_context = 0;
+ cp->retained = 0;
+ cp->dropped = 0;
+ cp->log_delay = DC_DEF_LOG_DELAY;
+ cp->upd_log_stamp = cp->get_log_stamp =
+ cp->del_log_stamp = cp->seq_log_stamp = 0;
+
+ return (cp);
+}
+
+/* dict_cache_close - close cache file */
+
+void dict_cache_close(DICT_CACHE *cp)
+{
+
+ /*
+ * Destroy the DICT_CACHE object.
+ */
+ myfree(cp->name);
+ dict_cache_control(cp, DICT_CACHE_CTL_INTERVAL, 0, DICT_CACHE_CTL_END);
+ dict_close(cp->db);
+ if (cp->saved_curr_key)
+ myfree(cp->saved_curr_key);
+ if (cp->saved_curr_val)
+ myfree(cp->saved_curr_val);
+ myfree((void *) cp);
+}
+
+/* dict_cache_name - get the cache name */
+
+const char *dict_cache_name(DICT_CACHE *cp)
+{
+
+ /*
+ * This is used for verbose logging or warning messages, so the cost of
+ * call is only made where needed (well sort off - code that does not
+ * execute still presents overhead for the processor pipeline, processor
+ * cache, etc).
+ */
+ return (cp->name);
+}
+
+ /*
+ * Test driver with support for interleaved access. First, enter a number of
+ * requests to look up, update or delete a sequence of cache entries, then
+ * interleave those sequences with the "run" command.
+ */
+#ifdef TEST
+#include <msg_vstream.h>
+#include <vstring_vstream.h>
+#include <argv.h>
+#include <stringops.h>
+
+#define DELIMS " "
+#define USAGE "\n\tTo manage settings:" \
+ "\n\tverbose <level> (verbosity level)" \
+ "\n\telapsed <level> (0=don't show elapsed time)" \
+ "\n\tlmdb_map_size <limit> (initial LMDB size limit)" \
+ "\n\tcache <type>:<name> (switch to named database)" \
+ "\n\tstatus (show map size, cache, pending requests)" \
+ "\n\n\tTo manage pending requests:" \
+ "\n\treset (discard pending requests)" \
+ "\n\trun (execute pending requests in interleaved order)" \
+ "\n\n\tTo add a pending request:" \
+ "\n\tquery <key-suffix> <count> (negative to reverse order)" \
+ "\n\tupdate <key-suffix> <count> (negative to reverse order)" \
+ "\n\tdelete <key-suffix> <count> (negative to reverse order)" \
+ "\n\tpurge <key-suffix>" \
+ "\n\tcount <key-suffix>"
+
+ /*
+ * For realism, open the cache with the same flags as postscreen(8) and
+ * verify(8).
+ */
+#define DICT_CACHE_OPEN_FLAGS (DICT_FLAG_DUP_REPLACE | DICT_FLAG_SYNC_UPDATE | \
+ DICT_FLAG_OPEN_LOCK)
+
+ /*
+ * Storage for one request to access a sequence of cache entries.
+ */
+typedef struct DICT_CACHE_SREQ {
+ int flags; /* per-request: reverse, purge */
+ char *cmd; /* command for status report */
+ void (*action) (struct DICT_CACHE_SREQ *, DICT_CACHE *, VSTRING *);
+ char *suffix; /* key suffix */
+ int done; /* progress indicator */
+ int todo; /* number of entries to process */
+ int first_next; /* first/next */
+} DICT_CACHE_SREQ;
+
+#define DICT_CACHE_SREQ_FLAG_PURGE (1<<1) /* purge instead of count */
+#define DICT_CACHE_SREQ_FLAG_REVERSE (1<<2) /* reverse instead of forward */
+
+#define DICT_CACHE_SREQ_LIMIT 10
+
+ /*
+ * All test requests combined.
+ */
+typedef struct DICT_CACHE_TEST {
+ int flags; /* exclusion flags */
+ int size; /* allocated slots */
+ int used; /* used slots */
+ DICT_CACHE_SREQ job_list[1]; /* actually, a bunch */
+} DICT_CACHE_TEST;
+
+#define DICT_CACHE_TEST_FLAG_ITER (1<<0) /* count or purge */
+
+#define STR(x) vstring_str(x)
+
+int show_elapsed = 1; /* show elapsed time */
+
+#ifdef HAS_LMDB
+extern size_t dict_lmdb_map_size; /* LMDB-specific */
+
+#endif
+
+/* usage - command-line usage message */
+
+static NORETURN usage(const char *progname)
+{
+ msg_fatal("usage: %s (no argument)", progname);
+}
+
+/* make_tagged_key - make tagged search key */
+
+static void make_tagged_key(VSTRING *bp, DICT_CACHE_SREQ *cp)
+{
+ if (cp->done < 0)
+ msg_panic("make_tagged_key: bad done count: %d", cp->done);
+ if (cp->todo < 1)
+ msg_panic("make_tagged_key: bad todo count: %d", cp->todo);
+ vstring_sprintf(bp, "%d-%s",
+ (cp->flags & DICT_CACHE_SREQ_FLAG_REVERSE) ?
+ cp->todo - cp->done - 1 : cp->done, cp->suffix);
+}
+
+/* create_requests - create request list */
+
+static DICT_CACHE_TEST *create_requests(int count)
+{
+ DICT_CACHE_TEST *tp;
+ DICT_CACHE_SREQ *cp;
+
+ tp = (DICT_CACHE_TEST *) mymalloc(sizeof(DICT_CACHE_TEST) +
+ (count - 1) *sizeof(DICT_CACHE_SREQ));
+ tp->flags = 0;
+ tp->size = count;
+ tp->used = 0;
+ for (cp = tp->job_list; cp < tp->job_list + count; cp++) {
+ cp->flags = 0;
+ cp->cmd = 0;
+ cp->action = 0;
+ cp->suffix = 0;
+ cp->todo = 0;
+ cp->first_next = DICT_SEQ_FUN_FIRST;
+ }
+ return (tp);
+}
+
+/* reset_requests - reset request list */
+
+static void reset_requests(DICT_CACHE_TEST *tp)
+{
+ DICT_CACHE_SREQ *cp;
+
+ tp->flags = 0;
+ tp->used = 0;
+ for (cp = tp->job_list; cp < tp->job_list + tp->size; cp++) {
+ cp->flags = 0;
+ if (cp->cmd) {
+ myfree(cp->cmd);
+ cp->cmd = 0;
+ }
+ cp->action = 0;
+ if (cp->suffix) {
+ myfree(cp->suffix);
+ cp->suffix = 0;
+ }
+ cp->todo = 0;
+ cp->first_next = DICT_SEQ_FUN_FIRST;
+ }
+}
+
+/* free_requests - destroy request list */
+
+static void free_requests(DICT_CACHE_TEST *tp)
+{
+ reset_requests(tp);
+ myfree((void *) tp);
+}
+
+/* run_requests - execute pending requests in interleaved order */
+
+static void run_requests(DICT_CACHE_TEST *tp, DICT_CACHE *dp, VSTRING *bp)
+{
+ DICT_CACHE_SREQ *cp;
+ int todo;
+ struct timeval start;
+ struct timeval finish;
+ struct timeval elapsed;
+
+ if (dp == 0) {
+ msg_warn("no cache");
+ return;
+ }
+ GETTIMEOFDAY(&start);
+ do {
+ todo = 0;
+ for (cp = tp->job_list; cp < tp->job_list + tp->used; cp++) {
+ if (cp->done < cp->todo) {
+ todo = 1;
+ cp->action(cp, dp, bp);
+ }
+ }
+ } while (todo);
+ GETTIMEOFDAY(&finish);
+ timersub(&finish, &start, &elapsed);
+ if (show_elapsed)
+ vstream_printf("Elapsed: %g\n",
+ elapsed.tv_sec + elapsed.tv_usec / 1000000.0);
+
+ reset_requests(tp);
+}
+
+/* show_status - show settings and pending requests */
+
+static void show_status(DICT_CACHE_TEST *tp, DICT_CACHE *dp)
+{
+ DICT_CACHE_SREQ *cp;
+
+#ifdef HAS_LMDB
+ vstream_printf("lmdb_map_size\t%ld\n", (long) dict_lmdb_map_size);
+#endif
+ vstream_printf("cache\t%s\n", dp ? dp->name : "(none)");
+
+ if (tp->used == 0)
+ vstream_printf("No pending requests\n");
+ else
+ vstream_printf("%s\t%s\t%s\t%s\t%s\t%s\n",
+ "cmd", "dir", "suffix", "count", "done", "first/next");
+
+ for (cp = tp->job_list; cp < tp->job_list + tp->used; cp++)
+ if (cp->todo > 0)
+ vstream_printf("%s\t%s\t%s\t%d\t%d\t%d\n",
+ cp->cmd,
+ (cp->flags & DICT_CACHE_SREQ_FLAG_REVERSE) ?
+ "reverse" : "forward",
+ cp->suffix ? cp->suffix : "(null)", cp->todo,
+ cp->done, cp->first_next);
+}
+
+/* query_action - lookup cache entry */
+
+static void query_action(DICT_CACHE_SREQ *cp, DICT_CACHE *dp, VSTRING *bp)
+{
+ const char *lookup;
+
+ make_tagged_key(bp, cp);
+ if ((lookup = dict_cache_lookup(dp, STR(bp))) == 0) {
+ if (dp->error)
+ msg_warn("query_action: query failed: %s: %m", STR(bp));
+ else
+ msg_warn("query_action: query failed: %s", STR(bp));
+ } else if (strcmp(STR(bp), lookup) != 0) {
+ msg_warn("lookup result \"%s\" differs from key \"%s\"",
+ lookup, STR(bp));
+ }
+ cp->done += 1;
+}
+
+/* update_action - update cache entry */
+
+static void update_action(DICT_CACHE_SREQ *cp, DICT_CACHE *dp, VSTRING *bp)
+{
+ make_tagged_key(bp, cp);
+ if (dict_cache_update(dp, STR(bp), STR(bp)) != 0) {
+ if (dp->error)
+ msg_warn("update_action: update failed: %s: %m", STR(bp));
+ else
+ msg_warn("update_action: update failed: %s", STR(bp));
+ }
+ cp->done += 1;
+}
+
+/* delete_action - delete cache entry */
+
+static void delete_action(DICT_CACHE_SREQ *cp, DICT_CACHE *dp, VSTRING *bp)
+{
+ make_tagged_key(bp, cp);
+ if (dict_cache_delete(dp, STR(bp)) != 0) {
+ if (dp->error)
+ msg_warn("delete_action: delete failed: %s: %m", STR(bp));
+ else
+ msg_warn("delete_action: delete failed: %s", STR(bp));
+ }
+ cp->done += 1;
+}
+
+/* iter_action - iterate over cache and act on entries with given suffix */
+
+static void iter_action(DICT_CACHE_SREQ *cp, DICT_CACHE *dp, VSTRING *bp)
+{
+ const char *cache_key;
+ const char *cache_val;
+ const char *what;
+ const char *suffix;
+
+ if (dict_cache_sequence(dp, cp->first_next, &cache_key, &cache_val) == 0) {
+ if (strcmp(cache_key, cache_val) != 0)
+ msg_warn("value \"%s\" differs from key \"%s\"",
+ cache_val, cache_key);
+ suffix = cache_key + strspn(cache_key, "0123456789");
+ if (suffix[0] == '-' && strcmp(suffix + 1, cp->suffix) == 0) {
+ cp->done += 1;
+ cp->todo = cp->done + 1; /* XXX */
+ if ((cp->flags & DICT_CACHE_SREQ_FLAG_PURGE)
+ && dict_cache_delete(dp, cache_key) != 0) {
+ if (dp->error)
+ msg_warn("purge_action: delete failed: %s: %m", STR(bp));
+ else
+ msg_warn("purge_action: delete failed: %s", STR(bp));
+ }
+ }
+ cp->first_next = DICT_SEQ_FUN_NEXT;
+ } else {
+ what = (cp->flags & DICT_CACHE_SREQ_FLAG_PURGE) ? "purge" : "count";
+ if (dp->error)
+ msg_warn("%s error after %d: %m", what, cp->done);
+ else
+ vstream_printf("suffix=%s %s=%d\n", cp->suffix, what, cp->done);
+ cp->todo = 0;
+ }
+}
+
+ /*
+ * Table-driven support.
+ */
+typedef struct DICT_CACHE_SREQ_INFO {
+ const char *name;
+ int argc;
+ void (*action) (DICT_CACHE_SREQ *, DICT_CACHE *, VSTRING *);
+ int test_flags;
+ int req_flags;
+} DICT_CACHE_SREQ_INFO;
+
+static DICT_CACHE_SREQ_INFO req_info[] = {
+ {"query", 3, query_action},
+ {"update", 3, update_action},
+ {"delete", 3, delete_action},
+ {"count", 2, iter_action, DICT_CACHE_TEST_FLAG_ITER},
+ {"purge", 2, iter_action, DICT_CACHE_TEST_FLAG_ITER, DICT_CACHE_SREQ_FLAG_PURGE},
+ 0,
+};
+
+/* add_request - add a request to the list */
+
+static void add_request(DICT_CACHE_TEST *tp, ARGV *argv)
+{
+ DICT_CACHE_SREQ_INFO *rp;
+ DICT_CACHE_SREQ *cp;
+ int req_flags;
+ int count;
+ char *cmd = argv->argv[0];
+ char *suffix = (argv->argc > 1 ? argv->argv[1] : 0);
+ char *todo = (argv->argc > 2 ? argv->argv[2] : "1"); /* XXX */
+
+ if (tp->used >= tp->size) {
+ msg_warn("%s: request list is full", cmd);
+ return;
+ }
+ for (rp = req_info; /* See below */ ; rp++) {
+ if (rp->name == 0) {
+ vstream_printf("usage: %s\n", USAGE);
+ return;
+ }
+ if (strcmp(rp->name, argv->argv[0]) == 0
+ && rp->argc == argv->argc)
+ break;
+ }
+ req_flags = rp->req_flags;
+ if (todo[0] == '-') {
+ req_flags |= DICT_CACHE_SREQ_FLAG_REVERSE;
+ todo += 1;
+ }
+ if (!alldig(todo) || (count = atoi(todo)) == 0) {
+ msg_warn("%s: bad count: %s", cmd, todo);
+ return;
+ }
+ if (tp->flags & rp->test_flags) {
+ msg_warn("%s: command conflicts with other command", cmd);
+ return;
+ }
+ tp->flags |= rp->test_flags;
+ cp = tp->job_list + tp->used;
+ cp->cmd = mystrdup(cmd);
+ cp->action = rp->action;
+ if (suffix)
+ cp->suffix = mystrdup(suffix);
+ cp->done = 0;
+ cp->flags = req_flags;
+ cp->todo = count;
+ tp->used += 1;
+}
+
+/* main - main program */
+
+int main(int argc, char **argv)
+{
+ DICT_CACHE_TEST *test_job;
+ VSTRING *inbuf = vstring_alloc(100);
+ char *bufp;
+ ARGV *args;
+ DICT_CACHE *cache = 0;
+ int stdin_is_tty;
+
+ msg_vstream_init(argv[0], VSTREAM_ERR);
+ if (argc != 1)
+ usage(argv[0]);
+
+
+ test_job = create_requests(DICT_CACHE_SREQ_LIMIT);
+
+ stdin_is_tty = isatty(0);
+
+ for (;;) {
+ if (stdin_is_tty) {
+ vstream_printf("> ");
+ vstream_fflush(VSTREAM_OUT);
+ }
+ if (vstring_fgets_nonl(inbuf, VSTREAM_IN) == 0)
+ break;
+ bufp = vstring_str(inbuf);
+ if (!stdin_is_tty) {
+ vstream_printf("> %s\n", bufp);
+ vstream_fflush(VSTREAM_OUT);
+ }
+ if (*bufp == '#')
+ continue;
+ args = argv_split(bufp, DELIMS);
+ if (argc == 0) {
+ vstream_printf("usage: %s\n", USAGE);
+ vstream_fflush(VSTREAM_OUT);
+ continue;
+ }
+ if (strcmp(args->argv[0], "verbose") == 0 && args->argc == 2) {
+ msg_verbose = atoi(args->argv[1]);
+ } else if (strcmp(args->argv[0], "elapsed") == 0 && args->argc == 2) {
+ show_elapsed = atoi(args->argv[1]);
+#ifdef HAS_LMDB
+ } else if (strcmp(args->argv[0], "lmdb_map_size") == 0 && args->argc == 2) {
+ dict_lmdb_map_size = atol(args->argv[1]);
+#endif
+ } else if (strcmp(args->argv[0], "cache") == 0 && args->argc == 2) {
+ if (cache)
+ dict_cache_close(cache);
+ cache = dict_cache_open(args->argv[1], O_CREAT | O_RDWR,
+ DICT_CACHE_OPEN_FLAGS);
+ } else if (strcmp(args->argv[0], "reset") == 0 && args->argc == 1) {
+ reset_requests(test_job);
+ } else if (strcmp(args->argv[0], "run") == 0 && args->argc == 1) {
+ run_requests(test_job, cache, inbuf);
+ } else if (strcmp(args->argv[0], "status") == 0 && args->argc == 1) {
+ show_status(test_job, cache);
+ } else {
+ add_request(test_job, args);
+ }
+ vstream_fflush(VSTREAM_OUT);
+ argv_free(args);
+ }
+
+ vstring_free(inbuf);
+ free_requests(test_job);
+ if (cache)
+ dict_cache_close(cache);
+ return (0);
+}
+
+#endif