Signed-off-by: Oleg Vasilev <oleg.vasilev(a)virtuozzo.com&gt; --- src/logging/log_handler.c | 26 -------------------------- src/logging/log_handler.h | 31 ++++++++++++++++++++++++++++--- 2 files changed, 28 insertions(+), 29 deletions(-) diff --git a/src/logging/log_handler.c b/src/logging/log_handler.c index 7342404b00..8fc7e9b2a8 100644 --- a/src/logging/log_handler.c +++ b/src/logging/log_handler.c @@ -22,11 +22,9 @@ #include "log_handler.h" #include "virerror.h" -#include "virobject.h" #include "virfile.h" #include "viralloc.h" #include "virlog.h" -#include "virrotatingfile.h" #include "viruuid.h" #include "virutil.h" @@ -42,30 +40,6 @@ VIR_LOG_INIT("logging.log_handler"); #define DEFAULT_MODE 0600 -typedef struct _virLogHandlerLogFile virLogHandlerLogFile; -struct _virLogHandlerLogFile { - virRotatingFileWriter *file; - int watch; - int pipefd; /* Read from QEMU via this */ - bool drained; - - char *driver; - unsigned char domuuid[VIR_UUID_BUFLEN]; - char *domname; -}; - -struct _virLogHandler { - virObjectLockable parent; - - bool privileged; - virLogDaemonConfig *config; - - virLogHandlerLogFile **files; - size_t nfiles; - - virLogHandlerShutdownInhibitor inhibitor; - void *opaque; -}; static virClass *virLogHandlerClass; static void virLogHandlerDispose(void *obj); diff --git a/src/logging/log_handler.h b/src/logging/log_handler.h index c9af033cd3..d473a19fc6 100644 --- a/src/logging/log_handler.h +++ b/src/logging/log_handler.h @@ -23,13 +23,38 @@ #include "internal.h" #include "virjson.h" #include "log_daemon_config.h" - -typedef struct _virLogHandler virLogHandler; - +#include "virobject.h" +#include "virrotatingfile.h" typedef void (*virLogHandlerShutdownInhibitor)(bool inhibit, void *opaque); +typedef struct _virLogHandlerLogFile virLogHandlerLogFile; +struct _virLogHandlerLogFile { + virRotatingFileWriter *file; + int watch; + int pipefd; /* Read from QEMU via this */ + bool drained; + + char *driver; + unsigned char domuuid[VIR_UUID_BUFLEN]; + char *domname; +}; + +typedef struct _virLogHandler virLogHandler; +struct _virLogHandler { + virObjectLockable parent; + + bool privileged; + virLogDaemonConfig *config; + + virLogHandlerLogFile **files; + size_t nfiles; + + virLogHandlerShutdownInhibitor inhibitor; + void *opaque; +}; + virLogHandler *virLogHandlerNew(bool privileged, virLogDaemonConfig *config, virLogHandlerShutdownInhibitor inhibitor, -- 2.38.1

Before, logs from deleted machines have been piling up, since there were no garbage collection mechanism. Now, virtlogd can be configured to periodically scan the log folder for orphan logs with no recent modifications and delete it. A single chain of recent and rotated logs is deleted in a single transaction. Signed-off-by: Oleg Vasilev <oleg.vasilev(a)virtuozzo.com&gt; --- po/POTFILES | 1 + src/logging/log_cleaner.c | 276 ++++++++++++++++++++++++++++++++++++++ src/logging/log_cleaner.h | 29 ++++ src/logging/log_handler.h | 2 + src/logging/meson.build | 1 + 5 files changed, 309 insertions(+) create mode 100644 src/logging/log_cleaner.c create mode 100644 src/logging/log_cleaner.h diff --git a/po/POTFILES b/po/POTFILES index 169e2a41dc..2fb6d18e27 100644 --- a/po/POTFILES +++ b/po/POTFILES @@ -123,6 +123,7 @@ src/locking/lock_driver_lockd.c src/locking/lock_driver_sanlock.c src/locking/lock_manager.c src/locking/sanlock_helper.c +src/logging/log_cleaner.c src/logging/log_daemon.c src/logging/log_daemon_dispatch.c src/logging/log_handler.c diff --git a/src/logging/log_cleaner.c b/src/logging/log_cleaner.c new file mode 100644 index 0000000000..03de9c17ee --- /dev/null +++ b/src/logging/log_cleaner.c @@ -0,0 +1,276 @@ +/* + * log_cleaner.c: cleans obsolete log files + * + * Copyright (C) 2022 Virtuozzo International GmbH + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2.1 of the License, or (at your option) any later version. + * + * This 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 + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this library; If not, see + * <http://www.gnu.org/licenses/>;. + */ + +#include <config.h> + +#include "log_cleaner.h" +#include "log_handler.h" + +#include "virerror.h" +#include "virobject.h" +#include "virfile.h" +#include "viralloc.h" +#include "virlog.h" +#include "virrotatingfile.h" +#include "virstring.h" + +#define VIR_FROM_THIS VIR_FROM_LOGGING + +/* Cleanup log root (/var/log/libvirt) and all subfolders (e.g. /var/log/libvirt/qemu) */ +#define CLEANER_LOG_DEPTH 1 +#define CLEANER_LOG_TIMEOUT_MS (24 * 3600 * 1000) /* One day */ +#define MAX_TIME ((time_t) G_MAXINT64) + +static GRegex *log_regex; + +typedef struct _virLogCleanerChain virLogCleanerChain; +struct _virLogCleanerChain { + int rotated_max_index; + time_t last_modified; +}; + +typedef struct _virLogCleanerData virLogCleanerData; +struct _virLogCleanerData { + virLogHandler *handler; + time_t oldest_to_keep; + GHashTable *chains; +}; + +static const char* +virLogCleanerParseFilename(const char* path, + int* rotated_index) +{ + g_autoptr(GMatchInfo) matchInfo = NULL; + g_autofree const char* rotated_index_str = NULL; + g_autofree const char *clear_path = NULL; + const char* chain_prefix = NULL; + + clear_path = realpath(path, NULL); + if (!clear_path) { + virReportSystemError(errno, + _("Failed to resolve path '%s'"), + path); + return NULL; + } + + if (!g_regex_match(log_regex, path, 0, &matchInfo)) { + return NULL; + } + + chain_prefix = g_match_info_fetch(matchInfo, 1); + if (!rotated_index) + return chain_prefix; + + *rotated_index = 0; + rotated_index_str = g_match_info_fetch(matchInfo, 2); + + if (!rotated_index_str) + return chain_prefix; + + if (virStrToLong_i(rotated_index_str+1, NULL, 10, rotated_index) < 0) { + virReportError(VIR_ERR_INTERNAL_ERROR, + _("Failed to parse rotated index from '%s'"), + rotated_index_str); + return NULL; + } + return chain_prefix; +} + +static void +virLogCleanerProcessFile(virLogCleanerData* data, + const char* path, + struct stat* sb) +{ + int rotated_index = 0; + g_autofree const char *chain_prefix = NULL; + virLogCleanerChain *chain; + + if (!S_ISREG(sb->st_mode)) { + return; + } + + chain_prefix = virLogCleanerParseFilename(path, &rotated_index); + + if (!chain_prefix) { + return; + } + + if (rotated_index > data->handler->config->max_backups) { + if (unlink(path) < 0) { + virReportSystemError(errno, _("Unable to delete %s"), path); + } + return; + } + + chain = g_hash_table_lookup(data->chains, chain_prefix); + + if (!chain) { + chain = g_new0(virLogCleanerChain, 1); + g_hash_table_insert(data->chains, (void *) chain_prefix, chain); + chain_prefix = NULL; /* Moved to hash table */ + } + + chain->last_modified = MAX(chain->last_modified, sb->st_mtime); + chain->rotated_max_index = MAX(chain->rotated_max_index, + rotated_index); +} + +static GHashTable* +virLogCleanerCreateTable(virLogHandler *handler) +{ + /* (const char*) chain_prefix -> (virLogCleanerChain*) chain */ + GHashTable *chains = g_hash_table_new_full(g_str_hash, g_str_equal, + g_free, g_free); + size_t i; + virLogHandlerLogFile *file; + const char *chain_prefix; + virLogCleanerChain* chain; + VIR_LOCK_GUARD lock = virObjectLockGuard(handler); + + for (i = 0; i < handler->nfiles; i++) { + file = handler->files[i]; + chain_prefix = virLogCleanerParseFilename(virRotatingFileWriterGetPath(file->file), + NULL); + if (!chain_prefix) { + continue; + } + + chain = g_new0(virLogCleanerChain, 1); + chain->last_modified = (time_t) G_MAXINT64; + g_hash_table_insert(chains, (void *) chain_prefix, chain); + } + + return chains; +} + +static void +virLogCleanerProcessFolder(virLogCleanerData *data, + const char *path, + int depth_left) +{ + DIR *dir; + struct dirent *entry; + struct stat sb; + + if (virDirOpenIfExists(&dir, path) < 0) + return; + + while (virDirRead(dir, &entry, path) > 0) { + g_autofree char *newpath = NULL; + if (STREQ(entry->d_name, ".")) + continue; + if (STREQ(entry->d_name, "..")) + continue; + + newpath = g_strdup_printf("%s/%s", path, entry->d_name); + + if (stat(newpath, &sb) < 0) { + virReportSystemError(errno, _("Unable to stat %s"), newpath); + continue; + } + + if (S_ISDIR(sb.st_mode)) { + if (depth_left > 0) + virLogCleanerProcessFolder(data, newpath, depth_left - 1); + continue; + } + + virLogCleanerProcessFile(data, newpath, &sb); + } + + virDirClose(dir); +} + +static void +virLogCleanerChainCB(gpointer key, + gpointer value, + gpointer user_data) +{ + const char* chain_prefix = key; + virLogCleanerChain* chain = value; + virLogCleanerData* data = user_data; + size_t i; + + if (chain->last_modified > data->oldest_to_keep) { + return; + } + + for (i = 0; i <= chain->rotated_max_index; i++) { + g_autofree char* path = NULL; + if (i == 0) { + path = g_strdup_printf("%s.log", chain_prefix); + } else { + path = g_strdup_printf("%s.log.%ld", chain_prefix, i); + } + if (unlink(path) < 0) { + virReportSystemError(errno, _("Unable to delete %s"), path); + } + } +} + +static void +virLogCleanerTimer(int timer G_GNUC_UNUSED, void* opaque) +{ + virLogHandler *handler = opaque; + virLogCleanerData data = { + .handler = handler, + .oldest_to_keep = time(NULL) - 3600 * 24 * handler->config->max_age_days, + .chains = virLogCleanerCreateTable(handler), + }; + + /* First prepare the hashmap of chains to delete */ + virLogCleanerProcessFolder(&data, + handler->config->log_root, + CLEANER_LOG_DEPTH); + g_hash_table_foreach(data.chains, virLogCleanerChainCB, &data); + g_hash_table_destroy(data.chains); +} + +int +virLogCleanerInit(virLogHandler *handler) +{ + if (handler->config->max_age_days <= 0) { + return 0; + } + + log_regex = g_regex_new("^(.*)\\.log(\\.(\\d+))?$", 0, 0, NULL); + if (!log_regex) { + virReportError(VIR_ERR_INTERNAL_ERROR, "%s", + _("Unable to compile regex")); + return -1; + } + + handler->cleanup_log_timer = virEventAddTimeout(CLEANER_LOG_TIMEOUT_MS, + virLogCleanerTimer, + handler, NULL); + return handler->cleanup_log_timer; +} + +void +virLogCleanerShutdown(virLogHandler *handler) +{ + if (handler->cleanup_log_timer != -1) { + virEventRemoveTimeout(handler->cleanup_log_timer); + handler->cleanup_log_timer = -1; + } + + g_regex_unref(log_regex); + log_regex = NULL; +} diff --git a/src/logging/log_cleaner.h b/src/logging/log_cleaner.h new file mode 100644 index 0000000000..1a9a94b68d --- /dev/null +++ b/src/logging/log_cleaner.h @@ -0,0 +1,29 @@ +/* + * log_cleaner.h: cleans obsolete log files + * + * Copyright (C) 2022 Virtuozzo International GmbH + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2.1 of the License, or (at your option) any later version. + * + * This 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 + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this library; If not, see + * <http://www.gnu.org/licenses/>;. + */ + +#pragma once + +#include "log_handler.h" + +int +virLogCleanerInit(virLogHandler *handler); + +void +virLogCleanerShutdown(virLogHandler *handler); diff --git a/src/logging/log_handler.h b/src/logging/log_handler.h index d473a19fc6..97dad27eda 100644 --- a/src/logging/log_handler.h +++ b/src/logging/log_handler.h @@ -48,6 +48,8 @@ struct _virLogHandler { bool privileged; virLogDaemonConfig *config; + int cleanup_log_timer; + virLogHandlerLogFile **files; size_t nfiles; diff --git a/src/logging/meson.build b/src/logging/meson.build index 7066f16fad..fa6af50fa6 100644 --- a/src/logging/meson.build +++ b/src/logging/meson.build @@ -30,6 +30,7 @@ log_daemon_sources = files( 'log_daemon_config.c', 'log_daemon_dispatch.c', 'log_handler.c', + 'log_cleaner.c', ) if conf.has('WITH_REMOTE') -- 2.38.1

On 09.01.2023 18:31, Martin Kletzander wrote: That's true, but I don't see any other simpler approach, which achieves the same result. We don't want the chains to be deleted in parts, so the only way I see is with two phases: - First, we aggregate information about the state of the filesystem - Then we do the deletion Do you have any suggestions this can be simplified. No, MAX should be used since we are looking for the most recent file. If the chain was written to recent enough, we would skip it during the deletion phase. But this is only for this function, which doesn't have any IO or anything heavy. The rest is clear to me, I will fix in a v3. Oleg

On 25.01.2023 19:49, Martin Kletzander wrote: For an alive log chain, we want to keep the rotated files as history. That was actually the issue raised by you: :) "One more thing is that if larger logs are rotated, then this would remove the old ones even if they are kept as number of backups. That seems like something that should be avoided (probably not even configurable)." By the way, should we have it in linters somewhere? That's the desired thing. For opened log files, we want to set "the-most-recent-time" aka G_MAXINT64 to prevent its deletion. I've added a comment explaining this. There should be a v3 nearby. Oleg

Actually use the log cleaner introduced by previous commit. Signed-off-by: Oleg Vasilev <oleg.vasilev(a)virtuozzo.com&gt; --- src/logging/log_handler.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/src/logging/log_handler.c b/src/logging/log_handler.c index 8fc7e9b2a8..a739211c7c 100644 --- a/src/logging/log_handler.c +++ b/src/logging/log_handler.c @@ -21,6 +21,7 @@ #include <config.h> #include "log_handler.h" +#include "log_cleaner.h" #include "virerror.h" #include "virfile.h" #include "viralloc.h" @@ -175,7 +176,15 @@ virLogHandlerNew(bool privileged, handler->inhibitor = inhibitor; handler->opaque = opaque; + if (virLogCleanerInit(handler) < 0) { + goto error; + } + return handler; + + error: + virObjectUnref(handler); + return NULL; } @@ -313,6 +322,8 @@ virLogHandlerDispose(void *obj) virLogHandler *handler = obj; size_t i; + virLogCleanerShutdown(handler); + for (i = 0; i < handler->nfiles; i++) { handler->inhibitor(false, handler->opaque); virLogHandlerLogFileFree(handler->files[i]); -- 2.38.1