/* * This file is distributed as part of the MariaDB Corporation MaxScale. It 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, * version 2. * * This program 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 * this program; if not, write to the Free Software Foundation, Inc., 51 * Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. * * Copyright MariaDB Corporation Ab 2013-2014 */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define MAX_PREFIXLEN 250 #define MAX_SUFFIXLEN 250 #define MAX_PATHLEN 512 #define MAXNBLOCKBUFS 10 /** for procname */ #if !defined(_GNU_SOURCE) # define _GNU_SOURCE #endif static const char LOGFILE_NAME_PREFIX[] = "maxscale"; static const char LOGFILE_NAME_SUFFIX[] = ".log"; extern char *program_invocation_name; extern char *program_invocation_short_name; typedef enum { BB_READY = 0x00, BB_FULL, BB_CLEARED } blockbuf_state_t; typedef enum { FILEWRITER_INIT, FILEWRITER_RUN, FILEWRITER_DONE } filewriter_state_t; /** * UNINIT means zeroed memory buffer allocated for the struct. * INIT means that struct members may have values, and memory may * have been allocated. Done function must check and free it. * RUN Struct is valid for run-time checking. * DONE means that possible memory allocations have been released. */ typedef enum { UNINIT = 0, INIT, RUN, DONE } flat_obj_state_t; /** * LOG_FLUSH_NO Do not flush after writing. * LOG_FLUSH_YES Flush after writing. */ enum log_flush { LOG_FLUSH_NO = 0, LOG_FLUSH_YES = 1 }; #if defined(SS_DEBUG) static int write_index; static int block_start_index; static int prevval; static simple_mutex_t msg_mutex; #endif /** * Default augmentation. */ static int DEFAULT_LOG_AUGMENTATION = 0; static struct { int augmentation; // Can change during the lifetime of log_manager. bool do_highprecision; // Can change during the lifetime of log_manager. bool do_syslog; // Can change during the lifetime of log_manager. bool do_maxlog; // Can change during the lifetime of log_manager. bool use_stdout; // Can NOT changed during the lifetime of log_manager. } log_config = { DEFAULT_LOG_AUGMENTATION, // augmentation false, // do_highprecision true, // do_syslog true, // do_maxlog false // use_stdout }; /** * Variable holding the enabled priorities information. * Used from logging macros. */ int mxs_log_enabled_priorities = 0; /** * Thread-specific struct variable for storing current session id and currently * enabled log files for the session. */ __thread mxs_log_info_t mxs_log_tls = {0, 0}; /** * Global counter for each log file type. It indicates for how many sessions * each log type is currently enabled. */ ssize_t mxs_log_session_count[LOG_DEBUG + 1] = {0}; /** * BUFSIZ comes from the system. It equals with block size or * its multiplication. */ #define MAX_LOGSTRLEN BUFSIZ /** * Path to directory in which all files are stored to shared memory * by the OS. */ const char* shm_pathname_prefix = "/dev/shm/"; /** Forward declarations */ typedef struct filewriter filewriter_t; typedef struct logfile logfile_t; typedef struct fnames_conf fnames_conf_t; typedef struct logmanager logmanager_t; /** * Global log manager pointer and lock variable. * lmlock protects logmanager access. */ static int lmlock; static logmanager_t* lm; static bool flushall_flag; static bool flushall_started_flag; static bool flushall_done_flag; /** This is used to detect if the initialization of the log manager has failed * and that it isn't initialized again after a failure has occurred. */ static bool fatal_error = false; /** Writer thread structure */ struct filewriter { #if defined(SS_DEBUG) skygw_chk_t fwr_chk_top; #endif flat_obj_state_t fwr_state; logmanager_t* fwr_logmgr; /** Physical files */ skygw_file_t* fwr_file; /** fwr_logmes is for messages from log clients */ skygw_message_t* fwr_logmes; /** fwr_clientmes is for messages to log clients */ skygw_message_t* fwr_clientmes; skygw_thread_t* fwr_thread; #if defined(SS_DEBUG) skygw_chk_t fwr_chk_tail; #endif }; /** * Log client's string is copied to block-sized log buffer, which is passed * to file writer thread. */ typedef struct blockbuf { #if defined(SS_DEBUG) skygw_chk_t bb_chk_top; #endif blockbuf_state_t bb_state; /**State of the block buffer*/ simple_mutex_t bb_mutex; /**< bb_buf_used, bb_isfull */ int bb_refcount; /**< protected by list mutex. #of clients */ // int bb_blankcount; /**< # of blanks used btw strings */ size_t bb_buf_size; size_t bb_buf_left; size_t bb_buf_used; char bb_buf[MAX_LOGSTRLEN]; #if defined(SS_DEBUG) skygw_chk_t bb_chk_tail; #endif } blockbuf_t; /** * logfile object corresponds to physical file(s) where * certain log is written. */ struct logfile { #if defined(SS_DEBUG) skygw_chk_t lf_chk_top; #endif flat_obj_state_t lf_state; bool lf_init_started; bool lf_store_shmem; logmanager_t* lf_lmgr; /** fwr_logmes is for messages from log clients */ skygw_message_t* lf_logmes; char* lf_filepath; /**< path to file used for logging */ char* lf_linkpath; /**< path to symlink file. */ const char* lf_name_prefix; const char* lf_name_suffix; int lf_name_seqno; char* lf_full_file_name; /**< complete log file name */ char* lf_full_link_name; /**< complete symlink name */ int lf_nfiles_max; size_t lf_file_size; /** list of block-sized log buffers */ mlist_t lf_blockbuf_list; size_t lf_buf_size; bool lf_flushflag; bool lf_rotateflag; int lf_spinlock; /**< lf_flushflag & lf_rotateflag */ int lf_npending_writes; #if defined(SS_DEBUG) skygw_chk_t lf_chk_tail; #endif }; struct fnames_conf { #if defined(SS_DEBUG) skygw_chk_t fn_chk_top; #endif flat_obj_state_t fn_state; char* fn_logpath; #if defined(SS_DEBUG) skygw_chk_t fn_chk_tail; #endif }; struct logmanager { #if defined(SS_DEBUG) skygw_chk_t lm_chk_top; #endif bool lm_enabled; simple_mutex_t lm_mutex; size_t lm_nlinks; /** fwr_logmes is for messages from log clients */ skygw_message_t* lm_logmes; /** fwr_clientmes is for messages to log clients */ skygw_message_t* lm_clientmes; fnames_conf_t lm_fnames_conf; logfile_t lm_logfile; filewriter_t lm_filewriter; mxs_log_target_t lm_target; #if defined(SS_DEBUG) skygw_chk_t lm_chk_tail; #endif }; /** * Type definition for string part. It is used in forming the log file name * from string parts provided by the client of log manager, as arguments. */ typedef struct strpart { const char* sp_string; struct strpart* sp_next; } strpart_t; /** Static function declarations */ static bool logfiles_init(logmanager_t* lmgr); static bool logfile_init(logfile_t* logfile, logmanager_t* logmanager, bool store_shmem); static void logfile_done(logfile_t* logfile); static void logfile_free_memory(logfile_t* lf); static void logfile_flush(logfile_t* lf); static void logfile_rotate(logfile_t* lf); static bool logfile_build_name(logfile_t* lf); static bool logfile_open_file(filewriter_t* fw, logfile_t* lf); static char* form_full_file_name(strpart_t* parts, logfile_t* lf, int seqnoidx); static bool filewriter_init(logmanager_t* logmanager, filewriter_t* fw); static void filewriter_done(filewriter_t* filewriter); static bool fnames_conf_init(fnames_conf_t* fn, const char* logdir); static void fnames_conf_done(fnames_conf_t* fn); static void fnames_conf_free_memory(fnames_conf_t* fn); static void* thr_filewriter_fun(void* data); static logfile_t* logmanager_get_logfile(logmanager_t* lm); static bool logmanager_register(bool writep); static void logmanager_unregister(void); static bool logmanager_init_nomutex(const char* ident, const char* logdir, mxs_log_target_t target); static void logmanager_done_nomutex(void); static int logmanager_write_log(int priority, enum log_flush flush, size_t prefix_len, size_t len, const char* str); static blockbuf_t* blockbuf_init(); static void blockbuf_node_done(void* bb_data); static char* blockbuf_get_writepos(blockbuf_t** p_bb, size_t str_len, bool flush); static void blockbuf_register(blockbuf_t* bb); static void blockbuf_unregister(blockbuf_t* bb); static char* add_slash(char* str); static bool check_file_and_path(char* filename, bool* writable, bool do_log); static bool file_is_symlink(char* filename); static int find_last_seqno(strpart_t* parts, int seqno, int seqnoidx); void flushall_logfiles(bool flush); bool thr_flushall_check(); static bool logmanager_init_nomutex(const char* ident, const char* logdir, mxs_log_target_t target) { fnames_conf_t* fn; filewriter_t* fw; int err; bool succ = false; lm = (logmanager_t *)calloc(1, sizeof(logmanager_t)); if (lm == NULL) { err = 1; goto return_succ; } lm->lm_target = (target == MXS_LOG_TARGET_DEFAULT ? MXS_LOG_TARGET_FS : target); #if defined(SS_DEBUG) lm->lm_chk_top = CHK_NUM_LOGMANAGER; lm->lm_chk_tail = CHK_NUM_LOGMANAGER; write_index = 0; block_start_index = 0; prevval = -1; simple_mutex_init(&msg_mutex, "Message mutex"); #endif lm->lm_clientmes = skygw_message_init(); lm->lm_logmes = skygw_message_init(); if (lm->lm_clientmes == NULL || lm->lm_logmes == NULL) { err = 1; goto return_succ; } fn = &lm->lm_fnames_conf; fw = &lm->lm_filewriter; fn->fn_state = UNINIT; fw->fwr_state = UNINIT; // The openlog call is always made, but a connection to the system logger will // not be made until a call to syslog is made. openlog(ident, LOG_PID | LOG_ODELAY, LOG_USER); /** Initialize configuration including log file naming info */ if (!fnames_conf_init(fn, logdir)) { err = 1; goto return_succ; } /** Initialize logfiles */ if (!logfiles_init(lm)) { err = 1; goto return_succ; } /** * Set global variable */ mxs_log_enabled_priorities = MXS_LOG_ERR | MXS_LOG_NOTICE | MXS_LOG_WARNING; /** * Initialize filewriter data and open the log file * for each log file type. */ if (!filewriter_init(lm, fw)) { err = 1; goto return_succ; } /** Initialize and start filewriter thread */ fw->fwr_thread = skygw_thread_init("filewriter thr", thr_filewriter_fun, (void *)fw); if (fw->fwr_thread == NULL) { err = 1; goto return_succ; } if ((err = skygw_thread_start(fw->fwr_thread)) != 0) { goto return_succ; } /** Wait message from filewriter_thr */ skygw_message_wait(fw->fwr_clientmes); succ = true; lm->lm_enabled = true; return_succ: if (err != 0) { /** This releases memory of all created objects */ logmanager_done_nomutex(); fprintf(stderr, "*\n* Error : Initializing log manager failed.\n*\n"); } return succ; } /** * Initializes log managing routines in MariaDB Corporation MaxScale. * * @param ident The syslog ident. If NULL, then the program name is used. * @param logdir The directory for the log file. If NULL logging will be made to stdout. * @param target Whether the log should be written to filesystem or shared memory. * Meaningless if logdir is NULL. * * @return true if succeed, otherwise false * */ bool mxs_log_init(const char* ident, const char* logdir, mxs_log_target_t target) { bool succ = false; acquire_lock(&lmlock); if (!lm) { succ = logmanager_init_nomutex(ident, logdir, target); } else { // TODO: This is not ok. If the parameters are different then // TODO: we pretend something is what it is not. succ = true; } release_lock(&lmlock); return succ; } /** * Release resources of log manager. * * Lock must have been acquired before calling * this function. */ static void logmanager_done_nomutex(void) { int i; logfile_t* lf; filewriter_t* fwr; fwr = &lm->lm_filewriter; if (fwr->fwr_state == RUN) { CHK_FILEWRITER(fwr); /** Inform filewriter thread and wait until it has stopped. */ skygw_thread_set_exitflag(fwr->fwr_thread, fwr->fwr_logmes, fwr->fwr_clientmes); /** Free thread memory */ skygw_thread_done(fwr->fwr_thread); } /** Free filewriter memory. */ filewriter_done(fwr); lf = logmanager_get_logfile(lm); /** Release logfile memory */ logfile_done(lf); closelog(); /** Release messages and finally logmanager memory */ fnames_conf_done(&lm->lm_fnames_conf); skygw_message_done(lm->lm_clientmes); skygw_message_done(lm->lm_logmes); /** Set global pointer NULL to prevent access to freed data. */ free(lm); lm = NULL; } /** * End execution of log manager * * Stops file writing thread, releases filewriter, and logfiles. * */ void mxs_log_finish(void) { acquire_lock(&lmlock); if (lm) { CHK_LOGMANAGER(lm); /** Mark logmanager unavailable */ lm->lm_enabled = false; /** Wait until all users have left or someone shuts down * logmanager between lock release and acquire. */ while (lm != NULL && lm->lm_nlinks != 0) { release_lock(&lmlock); pthread_yield(); acquire_lock(&lmlock); } /** Shut down if not already shutted down. */ if (lm) { ss_dassert(lm->lm_nlinks == 0); logmanager_done_nomutex(); } } release_lock(&lmlock); } static logfile_t* logmanager_get_logfile(logmanager_t* lmgr) { logfile_t* lf; CHK_LOGMANAGER(lmgr); lf = &lmgr->lm_logfile; if (lf->lf_state == RUN) { CHK_LOGFILE(lf); } return lf; } /** * Finds write position from block buffer for log string and writes there. * * Parameters: * * @param priority Syslog priority * @param flush indicates whether log string must be written to disk * immediately * @param rotate if set, closes currently open log file and opens a * new one * @param prefix_len length of prefix to be stripped away when syslogging * @param str_len length of formatted string (including terminating NULL). * @param str string to be written to log * * @return 0 if succeed, -1 otherwise * */ static int logmanager_write_log(int priority, enum log_flush flush, size_t prefix_len, size_t str_len, const char* str) { logfile_t* lf; char* wp; int err = 0; blockbuf_t* bb; blockbuf_t* bb_c; size_t timestamp_len; int i; // The config parameters are copied to local variables, because the values in // log_config may change during the course of the function, with would have // unpleasant side-effects. int do_highprecision = log_config.do_highprecision; int do_maxlog = log_config.do_maxlog; int do_syslog = log_config.do_syslog; assert(str); assert((priority & ~LOG_PRIMASK) == 0); CHK_LOGMANAGER(lm); // All messages are now logged to the error log file. lf = &lm->lm_logfile; CHK_LOGFILE(lf); /** Length of string that will be written, limited by bufsize */ size_t safe_str_len; /** Length of session id */ size_t sesid_str_len; size_t cmplen = 0; /** * 2 braces, 2 spaces and terminating char * If session id is stored to mxs_log_tls structure, allocate * room for session id too. */ if ((priority == LOG_INFO) && (mxs_log_tls.li_sesid != 0)) { sesid_str_len = 5 * sizeof(char) + get_decimal_len(mxs_log_tls.li_sesid); } else { sesid_str_len = 0; } if (do_highprecision) { timestamp_len = get_timestamp_len_hp(); } else { timestamp_len = get_timestamp_len(); } cmplen = sesid_str_len > 0 ? sesid_str_len - sizeof(char) : 0; bool overflow = false; /** Find out how much can be safely written with current block size */ if (timestamp_len - sizeof(char) + cmplen + str_len > lf->lf_buf_size) { safe_str_len = lf->lf_buf_size; overflow = true; } else { safe_str_len = timestamp_len - sizeof(char) + cmplen + str_len; } /** * Seek write position and register to block buffer. * Then print formatted string to write position. */ #if defined (SS_LOG_DEBUG) { char *copy, *tok; int tokval; simple_mutex_lock(&msg_mutex, true); copy = strdup(str); tok = strtok(copy, "|"); tok = strtok(NULL, "|"); if (strstr(str, "message|") && tok) { tokval = atoi(tok); if (prevval > 0) { ss_dassert(tokval == (prevval + 1)); } prevval = tokval; } free(copy); simple_mutex_unlock(&msg_mutex); } #endif /** Book space for log string from buffer */ if (do_maxlog) { // All messages are now logged to the error log file. wp = blockbuf_get_writepos(&bb, safe_str_len, flush); } else { wp = (char*)malloc(sizeof(char) * (timestamp_len - sizeof(char) + cmplen + str_len + 1)); } if (wp == NULL) { return -1; } #if defined (SS_LOG_DEBUG) { sprintf(wp, "[msg:%d]", atomic_add(&write_index, 1)); safe_str_len -= strlen(wp); wp += strlen(wp); } #endif /** * Write timestamp with at most characters * to wp. * Returned timestamp_len doesn't include terminating null. */ if (do_highprecision) { timestamp_len = snprint_timestamp_hp(wp, timestamp_len); } else { timestamp_len = snprint_timestamp(wp, timestamp_len); } if (sesid_str_len != 0) { /** * Write session id */ snprintf(wp + timestamp_len, sesid_str_len, "[%lu] ", mxs_log_tls.li_sesid); sesid_str_len -= 1; /*< don't calculate terminating char anymore */ } /** * Write next string to overwrite terminating null character * of the timestamp string. */ snprintf(wp + timestamp_len + sesid_str_len, safe_str_len-timestamp_len-sesid_str_len, "%s", str); /** Add an ellipsis to an overflowing message to signal truncation. */ if (overflow && safe_str_len > 4) { memset(wp + safe_str_len - 4, '.', 3); } /** write to syslog */ if (do_syslog) { // Strip away the timestamp and the prefix (e.g. "error : "). const char *message = wp + timestamp_len + prefix_len; switch (priority) { case LOG_EMERG: case LOG_ALERT: case LOG_CRIT: case LOG_ERR: case LOG_WARNING: case LOG_NOTICE: syslog(priority, "%s", message); break; default: // LOG_INFO and LOG_DEBUG messages are never written to syslog. break; } } /** remove double line feed */ if (wp[safe_str_len - 2] == '\n') { wp[safe_str_len - 2] = ' '; } wp[safe_str_len - 1] = '\n'; if (do_maxlog) { blockbuf_unregister(bb); } else { free(wp); } return err; } /** * Register writer to a block buffer. When reference counter is non-zero the * flusher thread doesn't write the block to disk. * * @param bb block buffer */ static void blockbuf_register(blockbuf_t* bb) { CHK_BLOCKBUF(bb); ss_dassert(bb->bb_refcount >= 0); atomic_add(&bb->bb_refcount, 1); } /** * Unregister writer from block buffer. If the buffer got filled up and there * are no other registered writers anymore, notify the flusher thread. * * @param bb block buffer */ static void blockbuf_unregister(blockbuf_t* bb) { logfile_t* lf; CHK_BLOCKBUF(bb); ss_dassert(bb->bb_refcount >= 1); lf = &lm->lm_logfile; CHK_LOGFILE(lf); /** * if this is the last client in a full buffer, send write request. */ if (atomic_add(&bb->bb_refcount, -1) == 1 && bb->bb_state == BB_FULL) { skygw_message_send(lf->lf_logmes); } ss_dassert(bb->bb_refcount >= 0); } /** * @node (write brief function description here) * * Parameters: * @param id - * * * @param str_len - * * * @return * * * @details List mutex now protects both the list and the contents of it. * TODO : It should be so that adding and removing nodes of the list is protected * by the list mutex. Buffer modifications should be protected by buffer * mutex. * */ static char* blockbuf_get_writepos(blockbuf_t** p_bb, size_t str_len, bool flush) { logfile_t* lf; mlist_t* bb_list; char* pos = NULL; mlist_node_t* node; blockbuf_t* bb; #if defined(SS_DEBUG) bool succ; #endif CHK_LOGMANAGER(lm); lf = &lm->lm_logfile; CHK_LOGFILE(lf); bb_list = &lf->lf_blockbuf_list; /** Lock list */ simple_mutex_lock(&bb_list->mlist_mutex, true); CHK_MLIST(bb_list); if (bb_list->mlist_nodecount > 0) { /** * At least block buffer exists on the list. */ node = bb_list->mlist_first; /** Loop over blockbuf list to find write position */ while (true) { CHK_MLIST_NODE(node); /** Unlock list */ simple_mutex_unlock(&bb_list->mlist_mutex); bb = (blockbuf_t *)node->mlnode_data; CHK_BLOCKBUF(bb); /** Lock buffer */ simple_mutex_lock(&bb->bb_mutex, true); if (bb->bb_state == BB_FULL || bb->bb_buf_left < str_len) { /** * This block buffer is too full. * Send flush request to file writer thread. This causes * flushing all buffers, and (eventually) frees buffer space. */ blockbuf_register(bb); bb->bb_state = BB_FULL; blockbuf_unregister(bb); /** Unlock buffer */ simple_mutex_unlock(&bb->bb_mutex); /** Lock list */ simple_mutex_lock(&bb_list->mlist_mutex, true); /** * If next node exists move forward. Else check if there is * space for a new block buffer on the list. */ if (node != bb_list->mlist_last) { node = node->mlnode_next; continue; } /** * All buffers on the list are full. */ if (bb_list->mlist_nodecount < bb_list->mlist_nodecount_max) { /** * New node is created */ if ((bb = blockbuf_init()) == NULL) { simple_mutex_unlock(&bb_list->mlist_mutex); return NULL; } CHK_BLOCKBUF(bb); /** * Increase version to odd to mark list update active * update. */ bb_list->mlist_versno += 1; ss_dassert(bb_list->mlist_versno % 2 == 1); ss_debug(succ =) mlist_add_data_nomutex(bb_list, bb); ss_dassert(succ); /** * Increase version to even to mark completion of update. */ bb_list->mlist_versno += 1; ss_dassert(bb_list->mlist_versno % 2 == 0); } else { /** * List and buffers are full. * Reset to the beginning of the list, and wait until * there is a block buffer with enough space. */ simple_mutex_unlock(&bb_list->mlist_mutex); simple_mutex_lock(&bb_list->mlist_mutex, true); node = bb_list->mlist_first; continue; } } else if (bb->bb_state == BB_CLEARED) { /** *Move the cleared buffer to the end of the list if it is the first one in the list */ simple_mutex_unlock(&bb->bb_mutex); simple_mutex_lock(&bb_list->mlist_mutex, true); if (node == bb_list->mlist_first) { if ((bb_list->mlist_nodecount > 1) && (node != bb_list->mlist_last)) { bb_list->mlist_last->mlnode_next = bb_list->mlist_first; bb_list->mlist_first = bb_list->mlist_first->mlnode_next; bb_list->mlist_last->mlnode_next->mlnode_next = NULL; bb_list->mlist_last = bb_list->mlist_last->mlnode_next; } ss_dassert(node == bb_list->mlist_last); simple_mutex_unlock(&bb_list->mlist_mutex); simple_mutex_lock(&bb->bb_mutex, true); bb->bb_state = BB_READY; simple_mutex_unlock(&bb->bb_mutex); simple_mutex_lock(&bb_list->mlist_mutex, true); node = bb_list->mlist_first; } else { if (node->mlnode_next) { node = node->mlnode_next; } else { node = bb_list->mlist_first; } continue; } } else if (bb->bb_state == BB_READY) { /** * There is space for new log string. */ break; } } /** while (true) */ } else { /** * Create the first block buffer to logfile's blockbuf list. */ if ((bb = blockbuf_init()) == NULL) { return NULL; } CHK_BLOCKBUF(bb); /** Lock buffer */ simple_mutex_lock(&bb->bb_mutex, true); /** * Increase version to odd to mark list update active update. */ bb_list->mlist_versno += 1; ss_dassert(bb_list->mlist_versno % 2 == 1); ss_debug(succ =) mlist_add_data_nomutex(bb_list, bb); ss_dassert(succ); /** * Increase version to even to mark completion of update. */ bb_list->mlist_versno += 1; ss_dassert(bb_list->mlist_versno % 2 == 0); /** Unlock list */ simple_mutex_unlock(&bb_list->mlist_mutex); } /* if (bb_list->mlist_nodecount > 0) */ ss_dassert(pos == NULL); ss_dassert(!(bb->bb_state == BB_FULL || bb->bb_buf_left < str_len)); ss_dassert(bb_list->mlist_nodecount <= bb_list->mlist_nodecount_max); /** * Registration to blockbuf adds reference for the write operation. * It indicates that client has allocated space from the buffer, * but not written yet. As long as refcount > 0 buffer can't be * written to disk. */ blockbuf_register(bb); *p_bb = bb; /** * At this point list mutex is held and bb points to a node with * enough space available. pos is not yet set. */ pos = &bb->bb_buf[bb->bb_buf_used]; bb->bb_buf_used += str_len; bb->bb_buf_left -= str_len; ss_dassert((pos >= &bb->bb_buf[0]) && (pos <= &bb->bb_buf[MAX_LOGSTRLEN-str_len])); /** read checkmark */ /** TODO: add buffer overflow checkmark chk_val = (int)bb->bb_buf[bb->bb_buf_used-count_len]; ss_dassert(chk_val == bb->bb_strcount); */ /** TODO : write next checkmark bb->bb_strcount += 1; memcpy(&bb->bb_buf[bb->bb_buf_used], &bb->bb_strcount, count_len); bb->bb_buf_used += count_len; bb->bb_buf_left -= count_len; */ /** * If flush flag is set, set buffer full. As a consequence, no-one * can write to it before it is flushed to disk. */ bb->bb_state = (flush == true ? BB_FULL : bb->bb_state); /** Unlock buffer */ simple_mutex_unlock(&bb->bb_mutex); return pos; } static void blockbuf_node_done(void* bb_data) { blockbuf_t* bb = (blockbuf_t *)bb_data; simple_mutex_done(&bb->bb_mutex); } static blockbuf_t* blockbuf_init() { blockbuf_t* bb; if ((bb = (blockbuf_t *) calloc(1, sizeof (blockbuf_t)))) { #if defined(SS_DEBUG) bb->bb_chk_top = CHK_NUM_BLOCKBUF; bb->bb_chk_tail = CHK_NUM_BLOCKBUF; #endif simple_mutex_init(&bb->bb_mutex, "Blockbuf mutex"); bb->bb_buf_left = MAX_LOGSTRLEN; bb->bb_buf_size = MAX_LOGSTRLEN; #if defined(SS_LOG_DEBUG) sprintf(bb->bb_buf, "[block:%d]", atomic_add(&block_start_index, 1)); bb->bb_buf_used += strlen(bb->bb_buf); bb->bb_buf_left -= strlen(bb->bb_buf); #endif CHK_BLOCKBUF(bb); } else { fprintf(stderr, "Error: Memory allocation failed when initializing log manager block buffers."); } return bb; } /** * Set log augmentation. * * @param bits One of the log_augmentation_t constants. */ void mxs_log_set_augmentation(int bits) { log_config.augmentation = bits & MXS_LOG_AUGMENTATION_MASK; } /** * Helper for skygw_log_write and friends. * * @param int The syslog priority. * @param file The name of the file where the logging was made. * @param int The line where the logging was made. * @param function The function where the logging was made. * @param prefix_len The length of the text to be stripped away when syslogging. * @param len Length of str, including terminating NULL. * @param str String * @param flush Whether the message should be flushed. * * @return 0 if the logging to at least one log succeeded. */ static int log_write(int priority, const char* file, int line, const char* function, size_t prefix_len, size_t len, const char* str, enum log_flush flush) { int rv = -1; if (logmanager_register(true)) { CHK_LOGMANAGER(lm); rv = logmanager_write_log(priority, flush, prefix_len, len, str); logmanager_unregister(); } return rv; } /** * @node Register as a logging client to logmanager. * * Parameters: * @param lmgr - * * * @return * * * @details Link count modify is protected by mutex. * */ static bool logmanager_register(bool writep) { bool succ = true; acquire_lock(&lmlock); if (lm == NULL || !lm->lm_enabled) { /** * Flush succeeds if logmanager is shut or shutting down. * returning false so that flusher doesn't access logmanager * and its members which would probabaly lead to NULL pointer * reference. */ if (!writep || fatal_error) { succ = false; goto return_succ; } ss_dassert(lm == NULL || (lm != NULL && !lm->lm_enabled)); /** * Wait until logmanager shut down has completed. * logmanager is enabled if someone already restarted * it between latest lock release, and acquire. */ while (lm != NULL && !lm->lm_enabled) { release_lock(&lmlock); pthread_yield(); acquire_lock(&lmlock); } if (lm == NULL) { // If someone is logging before the log manager has been inited, // or after the log manager has been finished, the messages are // written to stdout. succ = logmanager_init_nomutex(NULL, NULL, MXS_LOG_TARGET_DEFAULT); } } /** if logmanager existed or was succesfully restarted, increase link */ if (succ) { lm->lm_nlinks += 1; } return_succ: if (!succ) { fatal_error = true; } release_lock(&lmlock); return succ; } /** * @node Unregister from logmanager. * * Parameters: * @param lmgr - * * * @return * * * @details Link count modify is protected by mutex. * */ static void logmanager_unregister(void) { acquire_lock(&lmlock); lm->lm_nlinks -= 1; ss_dassert(lm->lm_nlinks >= 0); release_lock(&lmlock); } /** * @node Initialize log file naming parameters from call arguments * or from default functions in cases where arguments are not provided. * * @param fn The fnames_conf_t structure to initialize. * @param logdir The directory for the log file. If NULL logging will be made to stdout. * * @return True if the initialization was performed, false otherwise. * * @details Note that input parameter lenghts are checked here. * */ static bool fnames_conf_init(fnames_conf_t* fn, const char* logdir) { bool succ = false; /** * When init_started is set, clean must be done for it. */ fn->fn_state = INIT; #if defined(SS_DEBUG) fn->fn_chk_top = CHK_NUM_FNAMES; fn->fn_chk_tail = CHK_NUM_FNAMES; #endif const char* dir; if (logdir) { log_config.use_stdout = false; dir = logdir; } else { log_config.use_stdout = true; // TODO: Re-arrange things so that fn->fn_logpath can be NULL. dir = "/tmp"; } fn->fn_logpath = strdup(dir); if (fn->fn_logpath) { succ = true; fn->fn_state = RUN; CHK_FNAMES_CONF(fn); } return succ; } /** * @node Calls logfile initializer for each logfile. * * * Parameters: * @param lm Log manager pointer * * @return true if succeed, otherwise false. * * * @details If logfile is supposed to be located to shared memory * it is specified here. In the case of shared memory file, a soft * link is created to log directory. * * Motivation is performance. LOGFILE_DEBUG, for example, has so much data * that writing it to disk slows execution down remarkably. * */ static bool logfiles_init(logmanager_t* lm) { bool store_shmem = (lm->lm_target == MXS_LOG_TARGET_SHMEM); bool succ = logfile_init(&lm->lm_logfile, lm, store_shmem); if (!succ) { fprintf(stderr, "*\n* Error : Initializing log files failed.\n"); } return succ; } static void logfile_flush(logfile_t* lf) { CHK_LOGFILE(lf); acquire_lock(&lf->lf_spinlock); lf->lf_flushflag = true; release_lock(&lf->lf_spinlock); skygw_message_send(lf->lf_logmes); } /** * Set rotate flag for a log file and wake up the writer thread which then * performs the actual rotation task. * * @param lf logfile pointer */ static void logfile_rotate(logfile_t* lf) { CHK_LOGFILE(lf); acquire_lock(&lf->lf_spinlock); lf->lf_rotateflag = true; release_lock(&lf->lf_spinlock); skygw_message_send(lf->lf_logmes); } /** * Forms complete path name for logfile and tests that the file doesn't conflict * with any existing file and it is writable. * * @param lf logfile pointer * * @return true if succeed, false if failed * * @note Log file openings are not TOCTOU-safe. It is not likely that * multiple copies of same files are opened in parallel but it is possible by * using log manager in parallel with multiple processes and by configuring * log manager to use same directories among those processes. */ static bool logfile_build_name(logfile_t* lf) { bool namecreatefail; bool nameconflicts; bool store_shmem; bool writable; bool succ; strpart_t spart[3]; /*< string parts of which the file is composed of */ if (log_config.use_stdout) { // TODO: Refactor so that lf_full_file_name can be NULL in this case. lf->lf_full_file_name = strdup("stdout"); succ = true; // TODO: Refactor to get rid of the gotos. goto return_succ; } /** * sparts is an array but next pointers are used to walk through * the list of string parts. */ spart[0].sp_next = &spart[1]; spart[1].sp_next = &spart[2]; spart[2].sp_next = NULL; spart[1].sp_string = lf->lf_name_prefix; spart[2].sp_string = lf->lf_name_suffix; store_shmem = lf->lf_store_shmem; do { namecreatefail = false; nameconflicts = false; spart[0].sp_string = lf->lf_filepath; /** * Create name for log file. Seqno is added between prefix & * suffix (index == 2) */ lf->lf_full_file_name = form_full_file_name(spart, lf, 2); if (store_shmem) { spart[0].sp_string = lf->lf_linkpath; /** * Create name for link file */ lf->lf_full_link_name = form_full_file_name(spart, lf, 2); } /** * At least one of the files couldn't be created. Increase * sequence number and retry until succeeds. */ if (lf->lf_full_file_name == NULL || (store_shmem && lf->lf_full_link_name == NULL)) { namecreatefail = true; goto file_create_fail; } /** * If file exists but is different type, create fails and * new, increased sequence number is added to file name. */ if (check_file_and_path(lf->lf_full_file_name, &writable, true)) { /** Found similarly named file which isn't writable */ if (!writable || file_is_symlink(lf->lf_full_file_name)) { nameconflicts = true; goto file_create_fail; } } else { /** * Opening the file failed for some other reason than * existing non-writable file. Shut down. */ if (!writable) { succ = false; goto return_succ; } } if (store_shmem) { if (check_file_and_path(lf->lf_full_link_name, &writable, true)) { /** Found similarly named link which isn't writable */ if (!writable) { nameconflicts = true; } } else { /** * Opening the file failed for some other reason than * existing non-writable file. Shut down. */ if (!writable) { succ = false; goto return_succ; } } } file_create_fail: if (namecreatefail || nameconflicts) { lf->lf_name_seqno += 1; if (lf->lf_full_file_name != NULL) { free(lf->lf_full_file_name); lf->lf_full_file_name = NULL; } if (lf->lf_full_link_name != NULL) { free(lf->lf_full_link_name); lf->lf_full_link_name = NULL; } } } while (namecreatefail || nameconflicts); succ = true; return_succ: return succ; } /** * Opens a log file and writes header to the beginning of it. File name, FILE*, * and file descriptor are stored to skygw_file_t struct which is stored in * filewriter strcuture passed as parameter. * * @param fw filewriter pointer * @param lf logfile pointer * * @return true if succeed; the resulting skygw_file_t is written in filewriter, * false if failed. * */ static bool logfile_open_file(filewriter_t* fw, logfile_t* lf) { bool rv = true; if (log_config.use_stdout) { fw->fwr_file = skygw_file_alloc(lf->lf_full_file_name); fw->fwr_file->sf_file = stdout; } else if (lf->lf_store_shmem) { /** Create symlink pointing to log file */ fw->fwr_file = skygw_file_init(lf->lf_full_file_name, lf->lf_full_link_name); } else { /** Create normal disk-resident log file */ fw->fwr_file = skygw_file_init(lf->lf_full_file_name, NULL); } if (fw->fwr_file == NULL) { fprintf(stderr, "Error : opening logfile %s failed.\n", lf->lf_full_file_name); rv = false; } return rv; } /** * @node Combine all name parts from left to right. * * Parameters: * @param parts * * @param seqno specifies the the sequence number which will be added as a part * of full file name. seqno == -1 indicates that sequence number won't be used. * * @param seqnoidx Specifies the seqno position in the 'array' of name parts. * If seqno == -1 seqnoidx will be set -1 as well. * * @return Pointer to filename, of NULL if failed. * */ static char* form_full_file_name(strpart_t* parts, logfile_t* lf, int seqnoidx) { int i; int seqno; size_t s; size_t fnlen; char* filename = NULL; char* seqnostr = NULL; strpart_t* p; if (lf->lf_name_seqno != -1) { int file_sn; int link_sn = 0; const char* tmp = parts[0].sp_string; file_sn = find_last_seqno(parts, lf->lf_name_seqno, seqnoidx); if (lf->lf_linkpath != NULL) { tmp = parts[0].sp_string; parts[0].sp_string = lf->lf_linkpath; link_sn = find_last_seqno(parts, lf->lf_name_seqno, seqnoidx); parts[0].sp_string = tmp; } lf->lf_name_seqno = MAX(file_sn, link_sn); seqno = lf->lf_name_seqno; s = UINTLEN(seqno); seqnostr = (char *)malloc((int)s + 1); } else { /** * These magic numbers are needed to indicate this and * in subroutines that sequence number is not used. */ s = 0; seqnoidx = -1; seqno = lf->lf_name_seqno; } if (parts == NULL || parts->sp_string == NULL) { goto return_filename; } /** * Length of path, file name, separating slash, sequence number and * terminating character. */ fnlen = sizeof('/') + s + sizeof('\0'); p = parts; /** Calculate the combined length of all parts put together */ while (p->sp_string != NULL) { fnlen += strnlen(p->sp_string, NAME_MAX); if (p->sp_next == NULL) { break; } p = p->sp_next; } if (fnlen > NAME_MAX) { fprintf(stderr, "Error : Too long file name= %d.\n", (int)fnlen); goto return_filename; } filename = (char*)calloc(1, fnlen); if (seqnostr != NULL) { snprintf(seqnostr, s + 1, "%d", seqno); } for (i = 0, p = parts; p->sp_string != NULL; i++, p = p->sp_next) { if (seqnostr != NULL && i == seqnoidx) { strcat(filename, seqnostr); /*< add sequence number */ } strcat(filename, p->sp_string); if (p->sp_next == NULL) { break; } } return_filename: if (seqnostr != NULL) { free(seqnostr); } return filename; } /** * @node Allocate new buffer where argument string with a slash is copied. * Original string buffer is freed. * added. * * Parameters: * @param str - * * * @return * * * @details (write detailed description here) * */ static char* add_slash(char* str) { char* p = str; size_t plen = strlen(p); /** Add slash if missing */ if (p[plen - 1] != '/') { str = (char *)malloc(plen + 2); snprintf(str, plen + 2, "%s/", p); free(p); } return str; } /** * @node Check if the path and file exist in the local file system and if they do, * check if they are accessible and writable. * * Parameters: * @param filename file to be checked * * @param writable flag indicating whether file was found writable or not * if writable is NULL, check is skipped. * * @return true & writable if file exists and it is writable, * true & not writable if file exists but it can't be written, * false & writable if file doesn't exist but directory could be written, and * false & not writable if directory can't be written. * * @details Note, that a space character is written to the end of file. * TODO: recall what was the reason for not succeeding with simply * calling access, and fstat. vraa 26.11.13 */ static bool check_file_and_path(char* filename, bool* writable, bool do_log) { bool exists; if (filename == NULL) { exists = false; if (writable) { *writable = false; } } else { if (access(filename, F_OK) == 0) { exists = true; if (access(filename, W_OK) == 0) { if (writable) { *writable = true; } } else { if (do_log && file_is_symlink(filename)) { char errbuf[STRERROR_BUFLEN]; fprintf(stderr, "*\n* Error : Can't access " "file pointed to by %s due " "to %s.\n", filename, strerror_r(errno, errbuf, sizeof(errbuf))); } else if (do_log) { char errbuf[STRERROR_BUFLEN]; fprintf(stderr, "*\n* Error : Can't access %s due " "to %s.\n", filename, strerror_r(errno, errbuf, sizeof(errbuf))); } if (writable) { *writable = false; } } } else { exists = false; if (writable) { *writable = true; } } } return exists; } static bool file_is_symlink(char* filename) { int rc; bool succ = false; struct stat b; if (filename != NULL) { rc = lstat(filename, &b); if (rc != -1 && S_ISLNK(b.st_mode)) { succ = true; } } return succ; } /** * @node Initialize logfile structure. Form log file name, and optionally * link name. Create block buffer for logfile. * * Parameters: * @param logfile log file * @param logmanager log manager pointer * @param store_shmem flag to indicate whether log is physically written to shmem * * @return true if succeed, false otherwise */ static bool logfile_init(logfile_t* logfile, logmanager_t* logmanager, bool store_shmem) { bool succ = false; fnames_conf_t* fn = &logmanager->lm_fnames_conf; logfile->lf_state = INIT; #if defined(SS_DEBUG) logfile->lf_chk_top = CHK_NUM_LOGFILE; logfile->lf_chk_tail = CHK_NUM_LOGFILE; #endif logfile->lf_logmes = logmanager->lm_logmes; logfile->lf_name_prefix = LOGFILE_NAME_PREFIX; logfile->lf_name_suffix = LOGFILE_NAME_SUFFIX; logfile->lf_npending_writes = 0; logfile->lf_name_seqno = 1; logfile->lf_lmgr = logmanager; logfile->lf_flushflag = false; logfile->lf_rotateflag = false; logfile->lf_spinlock = 0; logfile->lf_store_shmem = store_shmem; logfile->lf_buf_size = MAX_LOGSTRLEN; /** * If file is stored in shared memory in /dev/shm, a link * pointing to shm file is created and located to the file * directory. */ if (store_shmem) { char* c; pid_t pid = getpid(); int len = strlen(shm_pathname_prefix) + strlen("maxscale.") + get_decimal_len((size_t)pid) + 1; c = (char *)calloc(len, sizeof(char)); if (c == NULL) { succ = false; goto return_with_succ; } sprintf(c, "%smaxscale.%d", shm_pathname_prefix, pid); logfile->lf_filepath = c; if (mkdir(c, S_IRWXU | S_IRWXG) != 0 && errno != EEXIST) { succ = false; goto return_with_succ; } logfile->lf_linkpath = strdup(fn->fn_logpath); logfile->lf_linkpath = add_slash(logfile->lf_linkpath); } else { logfile->lf_filepath = strdup(fn->fn_logpath); } logfile->lf_filepath = add_slash(logfile->lf_filepath); if (!(succ = logfile_build_name(logfile))) { goto return_with_succ; } /** * Create a block buffer list for log file. Clients' writes go to buffers * from where separate log flusher thread writes them to disk. */ if (mlist_init(&logfile->lf_blockbuf_list, NULL, strdup("logfile block buffer list"), blockbuf_node_done, MAXNBLOCKBUFS) == NULL) { ss_dfprintf(stderr, "*\n* Error : Initializing buffers for log files " "failed."); logfile_free_memory(logfile); goto return_with_succ; } succ = true; logfile->lf_state = RUN; CHK_LOGFILE(logfile); return_with_succ: if (!succ) { logfile_done(logfile); } ss_dassert(logfile->lf_state == RUN || logfile->lf_state == DONE); return succ; } /** * @node Flush logfile and free memory allocated for it. * * Parameters: * @param lf - * * * @return void * * * @details Operation is not protected. it is assumed that no one tries * to call logfile functions when logfile_done is called. * * It is also assumed that filewriter doesn't exist anymore. * * Logfile access could be protected by using exit flag and rwlock to protect * flag read/write. Lock would be held during log write operation by clients. * */ static void logfile_done(logfile_t* lf) { switch (lf->lf_state) { case RUN: CHK_LOGFILE(lf); ss_dassert(lf->lf_npending_writes == 0); /** fallthrough */ case INIT: /** Test if list is initialized before freeing it */ if (lf->lf_blockbuf_list.mlist_versno != 0) { mlist_done(&lf->lf_blockbuf_list); } logfile_free_memory(lf); lf->lf_state = DONE; /** fallthrough */ case DONE: case UNINIT: default: break; } } static void logfile_free_memory(logfile_t* lf) { if (lf->lf_filepath != NULL) free(lf->lf_filepath); if (lf->lf_linkpath != NULL) free(lf->lf_linkpath); if (lf->lf_full_link_name != NULL) free(lf->lf_full_link_name); if (lf->lf_full_file_name != NULL) free(lf->lf_full_file_name); } /** * @node Initialize filewriter data and open the log file for each log file type. * * @param logmanager Log manager struct * @param fw File writer struct * * @return true if succeed, false if failed * */ static bool filewriter_init(logmanager_t* logmanager, filewriter_t* fw) { bool succ = false; CHK_LOGMANAGER(logmanager); assert(logmanager->lm_clientmes); assert(logmanager->lm_logmes); fw->fwr_state = INIT; #if defined(SS_DEBUG) fw->fwr_chk_top = CHK_NUM_FILEWRITER; fw->fwr_chk_tail = CHK_NUM_FILEWRITER; #endif fw->fwr_logmgr = logmanager; /** Message from filewriter to clients */ fw->fwr_logmes = logmanager->lm_logmes; /** Message from clients to filewriter */ fw->fwr_clientmes = logmanager->lm_clientmes; logfile_t* lf = logmanager_get_logfile(logmanager); if (logfile_open_file(fw, lf)) { fw->fwr_state = RUN; CHK_FILEWRITER(fw); succ = true; } else { fprintf(stderr, "Error : opening log file %s failed. Exiting " "MaxScale\n", lf->lf_full_file_name); filewriter_done(fw); } ss_dassert(fw->fwr_state == RUN || fw->fwr_state == DONE); return succ; } static void filewriter_done(filewriter_t* fw) { switch (fw->fwr_state) { case RUN: CHK_FILEWRITER(fw); case INIT: fw->fwr_logmes = NULL; fw->fwr_clientmes = NULL; if (log_config.use_stdout) { skygw_file_free(fw->fwr_file); } else { skygw_file_close(fw->fwr_file, true); } fw->fwr_state = DONE; case DONE: case UNINIT: default: break; } } static bool thr_flush_file(logmanager_t *lm, filewriter_t *fwr) { /** * Get file pointer of current logfile. */ bool do_flushall = thr_flushall_check(); skygw_file_t *file = fwr->fwr_file; logfile_t *lf = &lm->lm_logfile; /** * read and reset logfile's flush- and rotateflag */ acquire_lock(&lf->lf_spinlock); bool flush_logfile = lf->lf_flushflag; bool rotate_logfile = lf->lf_rotateflag; lf->lf_flushflag = false; lf->lf_rotateflag = false; release_lock(&lf->lf_spinlock); /** * Log rotation : * Close current, and open a new file for the log. */ if (rotate_logfile) { bool succ; lf->lf_name_seqno += 1; /*< new sequence number */ if (!(succ = logfile_build_name(lf))) { lf->lf_name_seqno -= 1; /*< restore */ } else if ((succ = logfile_open_file(fwr, lf))) { if (log_config.use_stdout) { skygw_file_free(file); } else { skygw_file_close(file, false); /*< close old file */ } } if (!succ) { MXS_ERROR("Log rotation failed. " "Creating replacement file %s " "failed. Continuing " "logging to existing file.", lf->lf_full_file_name); } return true; } /** * get logfile's block buffer list */ mlist_t *bb_list = &lf->lf_blockbuf_list; #if defined(SS_DEBUG) simple_mutex_lock(&bb_list->mlist_mutex, true); CHK_MLIST(bb_list); simple_mutex_unlock(&bb_list->mlist_mutex); #endif mlist_node_t *node = bb_list->mlist_first; while (node != NULL) { int err = 0; CHK_MLIST_NODE(node); blockbuf_t *bb = (blockbuf_t *)node->mlnode_data; CHK_BLOCKBUF(bb); /** Lock block buffer */ simple_mutex_lock(&bb->bb_mutex, true); blockbuf_state_t flush_blockbuf = bb->bb_state; if (bb->bb_buf_used != 0 && ((flush_blockbuf == BB_FULL) || flush_logfile || do_flushall)) { /** * buffer is at least half-full * -> write to disk */ while (bb->bb_refcount > 0) { simple_mutex_unlock(&bb->bb_mutex); simple_mutex_lock(&bb->bb_mutex, true); } err = skygw_file_write(file, (void *)bb->bb_buf, bb->bb_buf_used, (flush_logfile || do_flushall)); if (err) { // TODO: Log this to syslog. char errbuf[STRERROR_BUFLEN]; fprintf(stderr, "Error : Writing to the log-file %s failed due to (%d, %s). " "Disabling writing to the log.", lf->lf_full_file_name, err, strerror_r(err, errbuf, sizeof(errbuf))); mxs_log_set_maxlog_enabled(false); } /** * Reset buffer's counters and mark * not full. */ bb->bb_buf_left = bb->bb_buf_size; bb->bb_buf_used = 0; memset(bb->bb_buf, 0, bb->bb_buf_size); bb->bb_state = BB_CLEARED; #if defined(SS_LOG_DEBUG) sprintf(bb->bb_buf,"[block:%d]", atomic_add(&block_start_index, 1)); bb->bb_buf_used += strlen(bb->bb_buf); bb->bb_buf_left -= strlen(bb->bb_buf); #endif } /** Release lock to block buffer */ simple_mutex_unlock(&bb->bb_mutex); size_t vn1; size_t vn2; /** Consistent lock-free read on the list */ do { while ((vn1 = bb_list->mlist_versno) % 2 != 0) { continue; } node = node->mlnode_next; vn2 = bb_list->mlist_versno; } while (vn1 != vn2 && node); } /* while (node != NULL) */ /** * Writer's exit flag was set after checking it. * Loop is restarted to ensure that all logfiles are * flushed. */ bool done = true; if (flushall_started_flag) { flushall_started_flag = false; flushall_done_flag = true; done = false; } return done; } /** * @node Writes block buffers of logfiles to physical log files on disk. * * Parameters: * @param data - thread context, skygw_thread_t * * * @return * * * @details Waits until receives wake-up message. Scans through block buffer * lists of each logfile object. * * Block buffer is written to log file if * 1. bb_state == true, * 2. logfile object's lf_flushflag == true, or * 3. skygw_thread_must_exit returns true. * * Log file is flushed (fsync'd) in cases #2 and #3. * * Concurrency control : block buffer is accessed by file writer (this) and * log clients. File writer reads and sets each logfile object's flushflag * with spinlock. Another protected section is when block buffer's metadata is * read, and optionally the write operation. * * When block buffer is marked full, logfile's flushflag is set, other * log clients don't try to access buffer(s). There may, however, be * active writes, on the block in parallel with file writer operations. * Each active write corresponds to bb_refcounter values. * On the other hand, file writer doesn't process the block buffer before * its refcount is zero. * * Every log file obj. has its own block buffer (linked) list. * List is accessed by log clients, which add nodes if necessary, and * by file writer which traverses the list and accesses block buffers * included in list nodes. * List modifications are protected with version numbers. * Before modification, version is increased by one to be odd. After the * completion, it is increased again to even. List can be read only when * version is even and read is consistent only if version hasn't changed * during the read. */ static void* thr_filewriter_fun(void* data) { skygw_thread_t* thr = (skygw_thread_t *)data; filewriter_t* fwr = (filewriter_t *)skygw_thread_get_data(thr); flushall_logfiles(false); CHK_FILEWRITER(fwr); ss_debug(skygw_thread_set_state(thr, THR_RUNNING)); /** Inform log manager about the state. */ skygw_message_send(fwr->fwr_clientmes); while (!skygw_thread_must_exit(thr)) { /** * Wait until new log arrival message appears. * Reset message to avoid redundant calls. */ skygw_message_wait(fwr->fwr_logmes); if (skygw_thread_must_exit(thr)) { flushall_logfiles(true); } /** Process all logfiles which have buffered writes. */ bool done = false; while (!done) { done = thr_flush_file(lm, fwr); if (!thr_flushall_check() && skygw_thread_must_exit(thr)) { flushall_logfiles(true); done = false; } } if (flushall_done_flag) { flushall_done_flag = false; flushall_logfiles(false); skygw_message_send(fwr->fwr_clientmes); } } /* while (!skygw_thread_must_exit) */ ss_debug(skygw_thread_set_state(thr, THR_STOPPED)); /** Inform log manager that file writer thread has stopped. */ skygw_message_send(fwr->fwr_clientmes); return NULL; } static void fnames_conf_done(fnames_conf_t* fn) { switch (fn->fn_state) { case RUN: CHK_FNAMES_CONF(fn); case INIT: fnames_conf_free_memory(fn); fn->fn_state = DONE; case DONE: case UNINIT: default: break; } } static void fnames_conf_free_memory(fnames_conf_t* fn) { free(fn->fn_logpath); } /** * Find the file with biggest sequence number from given directory and return * the sequence number. * * @param parts string parts of which the file name is composed of * @param seqno the sequence number to start with, if seqno is -1 just return * * @return the biggest sequence number used */ static int find_last_seqno(strpart_t* parts, int seqno, int seqnoidx) { strpart_t* p; char* snstr; int snstrlen; if (seqno == -1) { return seqno; } snstrlen = UINTLEN(INT_MAX); snstr = (char *)calloc(1, snstrlen); p = parts; while (true) { int i; char filename[NAME_MAX] = {0}; /** Form name with next seqno */ snprintf(snstr, snstrlen, "%d", seqno + 1); for (i = 0, p = parts; p->sp_string != NULL; i++, p = p->sp_next) { if (snstr != NULL && i == seqnoidx) { strncat(filename, snstr, NAME_MAX - 1); /*< add sequence number */ } strncat(filename, p->sp_string, NAME_MAX - 1); if (p->sp_next == NULL) { break; } } if (check_file_and_path(filename, NULL, false)) { seqno++; } else { break; } } free(snstr); return seqno; } bool thr_flushall_check() { bool rval = false; simple_mutex_lock(&lm->lm_mutex, true); rval = flushall_flag; if (rval && !flushall_started_flag && !flushall_done_flag) { flushall_started_flag = true; } simple_mutex_unlock(&lm->lm_mutex); return rval; } void flushall_logfiles(bool flush) { simple_mutex_lock(&lm->lm_mutex, true); flushall_flag = flush; simple_mutex_unlock(&lm->lm_mutex); } /** * Enable/disable syslog logging. * * @param enabled True, if high precision logging should be enabled, false if it should be disabled. */ void mxs_log_set_highprecision_enabled(bool enabled) { log_config.do_highprecision = enabled; MXS_NOTICE("highprecision logging is %s.", enabled ? "enabled" : "disabled"); } /** * Enable/disable syslog logging. * * @param enabled True, if syslog logging should be enabled, false if it should be disabled. */ void mxs_log_set_syslog_enabled(bool enabled) { log_config.do_syslog = enabled; MXS_NOTICE("syslog logging is %s.", enabled ? "enabled" : "disabled"); } /** * Enable/disable maxscale log logging. * * @param enabled True, if syslog logging should be enabled, false if it should be disabled. */ void mxs_log_set_maxlog_enabled(bool enabled) { log_config.do_maxlog = enabled; MXS_NOTICE("maxlog logging is %s.", enabled ? "enabled" : "disabled"); } /** * Explicitly ensure that all pending log messages are flushed. * * @return 0 if the flushing was successfully initiated, otherwise -1. * * Note that the return value only indicates whether the flushing was * successfully initiated, not whether the actual flushing has been * performed. */ int mxs_log_flush() { int err = -1; if (logmanager_register(false)) { CHK_LOGMANAGER(lm); logfile_t *lf = logmanager_get_logfile(lm); CHK_LOGFILE(lf); logfile_flush(lf); err = 0; logmanager_unregister(); } else { ss_dfprintf(stderr, "Can't register to logmanager, flushing failed.\n"); } return err; } /** * Explicitly ensure that all pending log messages are flushed. * * @return 0 if the flushing was successfully performed, otherwise -1. * * When the function returns 0, the flushing has been initiated and the * flushing thread has indicated that the operation has been performed. * However, 0 will be returned also in the case that the flushing thread * for, whatever reason, failed to actually flush the log. */ int mxs_log_flush_sync(void) { int err = 0; if (!log_config.use_stdout) { MXS_INFO("Starting log flushing to disk."); } /** If initialization of the log manager has not been done, lm pointer can be * NULL. */ // TODO: Why is logmanager_register() not called here? if (lm) { flushall_logfiles(true); if (skygw_message_send(lm->lm_logmes) == MES_RC_SUCCESS) { // TODO: Add error handling to skygw_message_wait. Now void. skygw_message_wait(lm->lm_clientmes); } else { err = -1; } } return err; } /** * Rotate the log-file. That is, close the current one and create a new one * with a larger sequence number. * * @return 0 if the rotating was successfully initiated, otherwise -1. * * Note that the return value only indicates whether the rotating was * successfully initiated, not whether the actual rotation has been * performed. */ int mxs_log_rotate() { int err = -1; if (logmanager_register(false)) { CHK_LOGMANAGER(lm); logfile_t *lf = logmanager_get_logfile(lm); CHK_LOGFILE(lf); MXS_NOTICE("Log rotation is called for %s.", lf->lf_full_file_name); logfile_rotate(lf); err = 0; logmanager_unregister(); } else { ss_dfprintf(stderr, "Can't register to logmanager, rotating failed.\n"); } return err; } static const char* priority_name(int priority) { switch (priority) { case LOG_EMERG: return "emercency"; case LOG_ALERT: return "alert"; case LOG_CRIT: return "critical"; case LOG_ERR: return "error"; case LOG_WARNING: return "warning"; case LOG_NOTICE: return "notice"; case LOG_INFO: return "informational"; case LOG_DEBUG: return "debug"; default: assert(!true); return "unknown"; } } /** * Enable/disable a particular syslog priority. * * @param priority One of the LOG_ERR etc. constants from sys/syslog.h. * @param enabled True if the priority should be enabled, false if it to be disabled. * * @return 0 if the priority was valid, -1 otherwise. */ int mxs_log_set_priority_enabled(int priority, bool enable) { int rv = -1; const char* text = (enable ? "enable" : "disable"); if ((priority & ~LOG_PRIMASK) == 0) { int bit = (1 << priority); if (enable) { // TODO: Put behind spinlock. mxs_log_enabled_priorities |= bit; } else { mxs_log_enabled_priorities &= ~bit; } MXS_NOTICE("The logging of %s messages has been %sd.", priority_name(priority), text); } else { MXS_ERROR("Attempt to %s unknown syslog priority %d.", text, priority); } return rv; } typedef struct log_prefix { const char* text; // The prefix, e.g. "error: " int len; // The length of the prefix without the trailing NULL. } log_prefix_t; static const char PREFIX_EMERG[] = "emerg : "; static const char PREFIX_ALERT[] = "alert : "; static const char PREFIX_CRIT[] = "crit : "; static const char PREFIX_ERROR[] = "error : "; static const char PREFIX_WARNING[] = "warning: "; static const char PREFIX_NOTICE[] = "notice : "; static const char PREFIX_INFO[] = "info : "; static const char PREFIX_DEBUG[] = "debug : "; static log_prefix_t priority_to_prefix(int priority) { assert((priority & ~LOG_PRIMASK) == 0); log_prefix_t prefix; switch (priority) { case LOG_EMERG: prefix.text = PREFIX_EMERG; prefix.len = sizeof(PREFIX_EMERG); break; case LOG_ALERT: prefix.text = PREFIX_ALERT; prefix.len = sizeof(PREFIX_ALERT); break; case LOG_CRIT: prefix.text = PREFIX_CRIT; prefix.len = sizeof(PREFIX_CRIT); break; case LOG_ERR: prefix.text = PREFIX_ERROR; prefix.len = sizeof(PREFIX_ERROR); break; case LOG_WARNING: prefix.text = PREFIX_WARNING; prefix.len = sizeof(PREFIX_WARNING); break; case LOG_NOTICE: prefix.text = PREFIX_NOTICE; prefix.len = sizeof(PREFIX_NOTICE); break; case LOG_INFO: prefix.text = PREFIX_INFO; prefix.len = sizeof(PREFIX_INFO); break; case LOG_DEBUG: prefix.text = PREFIX_DEBUG; prefix.len = sizeof(PREFIX_DEBUG); break; default: assert(!true); prefix.text = PREFIX_ERROR; prefix.len = sizeof(PREFIX_ERROR); break; } --prefix.len; // Remove trailing NULL. return prefix; } static enum log_flush priority_to_flush(int priority) { assert((priority & ~LOG_PRIMASK) == 0); switch (priority) { case LOG_EMERG: case LOG_ALERT: case LOG_CRIT: case LOG_ERR: return LOG_FLUSH_YES; default: assert(!true); case LOG_WARNING: case LOG_NOTICE: case LOG_INFO: case LOG_DEBUG: return LOG_FLUSH_NO; } } /** * Log a message of a particular priority. * * @param priority One of the syslog constants: LOG_ERR, LOG_WARNING, ... * @param file The name of the file where the message was logged. * @param line The line where the message was logged. * @param function The function where the message was logged. * @param format The printf format of the following arguments. * @param ... Optional arguments according to the format. */ int mxs_log_message(int priority, const char* file, int line, const char* function, const char* format, ...) { int err = 0; assert((priority & ~LOG_PRIMASK) == 0); if ((priority & ~LOG_PRIMASK) == 0) // Check that the priority is ok, { if (MXS_LOG_PRIORITY_IS_ENABLED(priority)) { va_list valist; /** * Find out the length of log string (to be formatted str). */ va_start(valist, format); int message_len = vsnprintf(NULL, 0, format, valist); va_end(valist); if (message_len >= 0) { log_prefix_t prefix = priority_to_prefix(priority); static const char FORMAT_FUNCTION[] = "(%s): "; // Other thread might change log_config.augmentation. int augmentation = log_config.augmentation; int augmentation_len = 0; switch (augmentation) { case MXS_LOG_AUGMENT_WITH_FUNCTION: augmentation_len = sizeof(FORMAT_FUNCTION) - 1; // Remove trailing 0 augmentation_len -= 2; // Remove the %s augmentation_len += strlen(function); break; default: break; } int buffer_len = prefix.len + augmentation_len + message_len + 1; // Trailing NULL if (buffer_len > MAX_LOGSTRLEN) { message_len -= (buffer_len - MAX_LOGSTRLEN); buffer_len = MAX_LOGSTRLEN; assert(prefix.len + augmentation_len + message_len + 1 == buffer_len); } char buffer[buffer_len]; char *prefix_text = buffer; char *augmentation_text = buffer + prefix.len; char *message_text = buffer + prefix.len + augmentation_len; strcpy(prefix_text, prefix.text); if (augmentation_len) { int len = 0; switch (augmentation) { case MXS_LOG_AUGMENT_WITH_FUNCTION: len = sprintf(augmentation_text, FORMAT_FUNCTION, function); break; default: assert(!true); } assert(len == augmentation_len); } va_start(valist, format); vsnprintf(message_text, message_len + 1, format, valist); va_end(valist); enum log_flush flush = priority_to_flush(priority); err = log_write(priority, file, line, function, prefix.len, buffer_len, buffer, flush); } } } else { MXS_WARNING("Invalid syslog priority: %d", priority); } return err; }