diff options
Diffstat (limited to 'libnetdata/log/log.c')
| -rw-r--r-- | libnetdata/log/log.c | 436 |
1 files changed, 436 insertions, 0 deletions
diff --git a/libnetdata/log/log.c b/libnetdata/log/log.c new file mode 100644 index 00000000..198e98bd --- /dev/null +++ b/libnetdata/log/log.c @@ -0,0 +1,436 @@ +// SPDX-License-Identifier: GPL-3.0-or-later + +#include "../libnetdata.h" + +int web_server_is_multithreaded = 1; + +const char *program_name = ""; +uint64_t debug_flags = DEBUG; + +int access_log_syslog = 1; +int error_log_syslog = 1; +int output_log_syslog = 1; // debug log + +int stdaccess_fd = -1; +FILE *stdaccess = NULL; + +const char *stdaccess_filename = NULL; +const char *stderr_filename = NULL; +const char *stdout_filename = NULL; + +void syslog_init(void) { + static int i = 0; + + if(!i) { + openlog(program_name, LOG_PID, LOG_DAEMON); + i = 1; + } +} + +#define LOG_DATE_LENGTH 26 + +static inline void log_date(char *buffer, size_t len) { + if(unlikely(!buffer || !len)) + return; + + time_t t; + struct tm *tmp, tmbuf; + + t = now_realtime_sec(); + tmp = localtime_r(&t, &tmbuf); + + if (tmp == NULL) { + buffer[0] = '\0'; + return; + } + + if (unlikely(strftime(buffer, len, "%Y-%m-%d %H:%M:%S", tmp) == 0)) + buffer[0] = '\0'; + + buffer[len - 1] = '\0'; +} + +static netdata_mutex_t log_mutex = NETDATA_MUTEX_INITIALIZER; +static inline void log_lock() { + netdata_mutex_lock(&log_mutex); +} +static inline void log_unlock() { + netdata_mutex_unlock(&log_mutex); +} + +static FILE *open_log_file(int fd, FILE *fp, const char *filename, int *enabled_syslog, int is_stdaccess, int *fd_ptr) { + int f, devnull = 0; + + if(!filename || !*filename || !strcmp(filename, "none") || !strcmp(filename, "/dev/null")) { + filename = "/dev/null"; + devnull = 1; + } + + if(!strcmp(filename, "syslog")) { + filename = "/dev/null"; + devnull = 1; + syslog_init(); + if(enabled_syslog) *enabled_syslog = 1; + } + else if(enabled_syslog) *enabled_syslog = 0; + + // don't do anything if the user is willing + // to have the standard one + if(!strcmp(filename, "system")) { + if(fd != -1 && !is_stdaccess) { + if(fd_ptr) *fd_ptr = fd; + return fp; + } + + filename = "stderr"; + } + + if(!strcmp(filename, "stdout")) + f = STDOUT_FILENO; + + else if(!strcmp(filename, "stderr")) + f = STDERR_FILENO; + + else { + f = open(filename, O_WRONLY | O_APPEND | O_CREAT, 0664); + if(f == -1) { + error("Cannot open file '%s'. Leaving %d to its default.", filename, fd); + if(fd_ptr) *fd_ptr = fd; + return fp; + } + } + + // if there is a level-2 file pointer + // flush it before switching the level-1 fds + if(fp) + fflush(fp); + + if(devnull && is_stdaccess) { + fd = -1; + fp = NULL; + } + + if(fd != f && fd != -1) { + // it automatically closes + int t = dup2(f, fd); + if (t == -1) { + error("Cannot dup2() new fd %d to old fd %d for '%s'", f, fd, filename); + close(f); + if(fd_ptr) *fd_ptr = fd; + return fp; + } + // info("dup2() new fd %d to old fd %d for '%s'", f, fd, filename); + close(f); + } + else fd = f; + + if(!fp) { + fp = fdopen(fd, "a"); + if (!fp) + error("Cannot fdopen() fd %d ('%s')", fd, filename); + else { + if (setvbuf(fp, NULL, _IOLBF, 0) != 0) + error("Cannot set line buffering on fd %d ('%s')", fd, filename); + } + } + + if(fd_ptr) *fd_ptr = fd; + return fp; +} + +void reopen_all_log_files() { + if(stdout_filename) + open_log_file(STDOUT_FILENO, stdout, stdout_filename, &output_log_syslog, 0, NULL); + + if(stderr_filename) + open_log_file(STDERR_FILENO, stderr, stderr_filename, &error_log_syslog, 0, NULL); + + if(stdaccess_filename) + stdaccess = open_log_file(stdaccess_fd, stdaccess, stdaccess_filename, &access_log_syslog, 1, &stdaccess_fd); +} + +void open_all_log_files() { + // disable stdin + open_log_file(STDIN_FILENO, stdin, "/dev/null", NULL, 0, NULL); + + open_log_file(STDOUT_FILENO, stdout, stdout_filename, &output_log_syslog, 0, NULL); + open_log_file(STDERR_FILENO, stderr, stderr_filename, &error_log_syslog, 0, NULL); + stdaccess = open_log_file(stdaccess_fd, stdaccess, stdaccess_filename, &access_log_syslog, 1, &stdaccess_fd); +} + +// ---------------------------------------------------------------------------- +// error log throttling + +time_t error_log_throttle_period = 1200; +unsigned long error_log_errors_per_period = 200; +unsigned long error_log_errors_per_period_backup = 0; + +int error_log_limit(int reset) { + static time_t start = 0; + static unsigned long counter = 0, prevented = 0; + + // fprintf(stderr, "FLOOD: counter=%lu, allowed=%lu, backup=%lu, period=%llu\n", counter, error_log_errors_per_period, error_log_errors_per_period_backup, (unsigned long long)error_log_throttle_period); + + // do not throttle if the period is 0 + if(error_log_throttle_period == 0) + return 0; + + // prevent all logs if the errors per period is 0 + if(error_log_errors_per_period == 0) +#ifdef NETDATA_INTERNAL_CHECKS + return 0; +#else + return 1; +#endif + + time_t now = now_monotonic_sec(); + if(!start) start = now; + + if(reset) { + if(prevented) { + char date[LOG_DATE_LENGTH]; + log_date(date, LOG_DATE_LENGTH); + fprintf(stderr, "%s: %s LOG FLOOD PROTECTION reset for process '%s' (prevented %lu logs in the last %ld seconds).\n" + , date + , program_name + , program_name + , prevented + , now - start + ); + } + + start = now; + counter = 0; + prevented = 0; + } + + // detect if we log too much + counter++; + + if(now - start > error_log_throttle_period) { + if(prevented) { + char date[LOG_DATE_LENGTH]; + log_date(date, LOG_DATE_LENGTH); + fprintf(stderr, "%s: %s LOG FLOOD PROTECTION resuming logging from process '%s' (prevented %lu logs in the last %ld seconds).\n" + , date + , program_name + , program_name + , prevented + , error_log_throttle_period + ); + } + + // restart the period accounting + start = now; + counter = 1; + prevented = 0; + + // log this error + return 0; + } + + if(counter > error_log_errors_per_period) { + if(!prevented) { + char date[LOG_DATE_LENGTH]; + log_date(date, LOG_DATE_LENGTH); + fprintf(stderr, "%s: %s LOG FLOOD PROTECTION too many logs (%lu logs in %ld seconds, threshold is set to %lu logs in %ld seconds). Preventing more logs from process '%s' for %ld seconds.\n" + , date + , program_name + , counter + , now - start + , error_log_errors_per_period + , error_log_throttle_period + , program_name + , start + error_log_throttle_period - now); + } + + prevented++; + + // prevent logging this error +#ifdef NETDATA_INTERNAL_CHECKS + return 0; +#else + return 1; +#endif + } + + return 0; +} + +// ---------------------------------------------------------------------------- +// debug log + +void debug_int( const char *file, const char *function, const unsigned long line, const char *fmt, ... ) { + va_list args; + + char date[LOG_DATE_LENGTH]; + log_date(date, LOG_DATE_LENGTH); + + va_start( args, fmt ); + printf("%s: %s DEBUG : %s : (%04lu@%-10.10s:%-15.15s): ", date, program_name, netdata_thread_tag(), line, file, function); + vprintf(fmt, args); + va_end( args ); + putchar('\n'); + + if(output_log_syslog) { + va_start( args, fmt ); + vsyslog(LOG_ERR, fmt, args ); + va_end( args ); + } + + fflush(stdout); +} + +// ---------------------------------------------------------------------------- +// info log + +void info_int( const char *file, const char *function, const unsigned long line, const char *fmt, ... ) +{ + va_list args; + + // prevent logging too much + if(error_log_limit(0)) return; + + if(error_log_syslog) { + va_start( args, fmt ); + vsyslog(LOG_INFO, fmt, args ); + va_end( args ); + } + + char date[LOG_DATE_LENGTH]; + log_date(date, LOG_DATE_LENGTH); + + log_lock(); + + va_start( args, fmt ); + if(debug_flags) fprintf(stderr, "%s: %s INFO : %s : (%04lu@%-10.10s:%-15.15s): ", date, program_name, netdata_thread_tag(), line, file, function); + else fprintf(stderr, "%s: %s INFO : %s : ", date, program_name, netdata_thread_tag()); + vfprintf( stderr, fmt, args ); + va_end( args ); + + fputc('\n', stderr); + + log_unlock(); +} + +// ---------------------------------------------------------------------------- +// error log + +#if defined(STRERROR_R_CHAR_P) +// GLIBC version of strerror_r +static const char *strerror_result(const char *a, const char *b) { (void)b; return a; } +#elif defined(HAVE_STRERROR_R) +// POSIX version of strerror_r +static const char *strerror_result(int a, const char *b) { (void)a; return b; } +#elif defined(HAVE_C__GENERIC) + +// what a trick! +// http://stackoverflow.com/questions/479207/function-overloading-in-c +static const char *strerror_result_int(int a, const char *b) { (void)a; return b; } +static const char *strerror_result_string(const char *a, const char *b) { (void)b; return a; } + +#define strerror_result(a, b) _Generic((a), \ + int: strerror_result_int, \ + char *: strerror_result_string \ + )(a, b) + +#else +#error "cannot detect the format of function strerror_r()" +#endif + +void error_int( const char *prefix, const char *file, const char *function, const unsigned long line, const char *fmt, ... ) { + // save a copy of errno - just in case this function generates a new error + int __errno = errno; + + va_list args; + + // prevent logging too much + if(error_log_limit(0)) return; + + if(error_log_syslog) { + va_start( args, fmt ); + vsyslog(LOG_ERR, fmt, args ); + va_end( args ); + } + + char date[LOG_DATE_LENGTH]; + log_date(date, LOG_DATE_LENGTH); + + log_lock(); + + va_start( args, fmt ); + if(debug_flags) fprintf(stderr, "%s: %s %-5.5s : %s : (%04lu@%-10.10s:%-15.15s): ", date, program_name, prefix, netdata_thread_tag(), line, file, function); + else fprintf(stderr, "%s: %s %-5.5s : %s : ", date, program_name, prefix, netdata_thread_tag()); + vfprintf( stderr, fmt, args ); + va_end( args ); + + if(__errno) { + char buf[1024]; + fprintf(stderr, " (errno %d, %s)\n", __errno, strerror_result(strerror_r(__errno, buf, 1023), buf)); + errno = 0; + } + else + fputc('\n', stderr); + + log_unlock(); +} + +void fatal_int( const char *file, const char *function, const unsigned long line, const char *fmt, ... ) { + va_list args; + + if(error_log_syslog) { + va_start( args, fmt ); + vsyslog(LOG_CRIT, fmt, args ); + va_end( args ); + } + + char date[LOG_DATE_LENGTH]; + log_date(date, LOG_DATE_LENGTH); + + log_lock(); + + va_start( args, fmt ); + if(debug_flags) fprintf(stderr, "%s: %s FATAL : %s : (%04lu@%-10.10s:%-15.15s): ", date, program_name, netdata_thread_tag(), line, file, function); + else fprintf(stderr, "%s: %s FATAL : %s :", date, program_name, netdata_thread_tag()); + vfprintf( stderr, fmt, args ); + va_end( args ); + + perror(" # "); + fputc('\n', stderr); + + log_unlock(); + + netdata_cleanup_and_exit(1); +} + +// ---------------------------------------------------------------------------- +// access log + +void log_access( const char *fmt, ... ) { + va_list args; + + if(access_log_syslog) { + va_start( args, fmt ); + vsyslog(LOG_INFO, fmt, args ); + va_end( args ); + } + + if(stdaccess) { + static netdata_mutex_t access_mutex = NETDATA_MUTEX_INITIALIZER; + + if(web_server_is_multithreaded) + netdata_mutex_lock(&access_mutex); + + char date[LOG_DATE_LENGTH]; + log_date(date, LOG_DATE_LENGTH); + fprintf(stdaccess, "%s: ", date); + + va_start( args, fmt ); + vfprintf( stdaccess, fmt, args ); + va_end( args ); + fputc('\n', stdaccess); + + if(web_server_is_multithreaded) + netdata_mutex_unlock(&access_mutex); + } +} |