From ca6d5472056ceee4b8ab320167e0ae8155a95985 Mon Sep 17 00:00:00 2001 From: Jo-Philipp Wich Date: Wed, 25 Feb 2015 20:42:03 +0100 Subject: [PATCH] ulog: introduce new simple logging api The ulog api is intended to be used by procd, fstools, ubox etc. to provide a generic logging api for early boot messages and automatic switching between syslog / kmsg / stdout depending on the way the process is executed. Signed-off-by: Jo-Philipp Wich --- CMakeLists.txt | 2 +- ulog.c | 163 +++++++++++++++++++++++++++++++++++++++++++++++++ ulog.h | 42 +++++++++++++ 3 files changed, 206 insertions(+), 1 deletion(-) create mode 100644 ulog.c create mode 100644 ulog.h diff --git a/CMakeLists.txt b/CMakeLists.txt index ddd5533..58381da 100644 --- a/CMakeLists.txt +++ b/CMakeLists.txt @@ -14,7 +14,7 @@ IF(JSONC_FOUND) INCLUDE_DIRECTORIES(${JSONC_INCLUDE_DIRS}) ENDIF() -SET(SOURCES avl.c avl-cmp.c blob.c blobmsg.c uloop.c usock.c ustream.c ustream-fd.c vlist.c utils.c safe_list.c runqueue.c md5.c kvlist.c) +SET(SOURCES avl.c avl-cmp.c blob.c blobmsg.c uloop.c usock.c ustream.c ustream-fd.c vlist.c utils.c safe_list.c runqueue.c md5.c kvlist.c ulog.c) ADD_LIBRARY(ubox SHARED ${SOURCES}) ADD_LIBRARY(ubox-static STATIC ${SOURCES}) diff --git a/ulog.c b/ulog.c new file mode 100644 index 0000000..f7c92d8 --- /dev/null +++ b/ulog.c @@ -0,0 +1,163 @@ +/* + * ulog - simple logging functions + * + * Copyright (C) 2015 Jo-Philipp Wich + * + * Permission to use, copy, modify, and/or distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + */ + +#include "ulog.h" + +#include +#include +#include +#include +#include + +static int _ulog_channels = -1; +static int _ulog_facility = -1; +static int _ulog_threshold = LOG_DEBUG; +static int _ulog_initialized = 0; +static const char *_ulog_ident = NULL; + +static const char *ulog_default_ident(void) +{ + FILE *self; + static char line[64]; + char *p = NULL; + + if ((self = fopen("/proc/self/status", "r")) != NULL) { + while (fgets(line, sizeof(line), self)) { + if (!strncmp(line, "Name:", 5)) { + strtok(line, "\t\n"); + p = strtok(NULL, "\t\n"); + break; + } + } + fclose(self); + } + + return p; +} + +static void ulog_defaults(void) +{ + char *env; + + if (_ulog_initialized) + return; + + env = getenv("PREINIT"); + + if (_ulog_channels < 0) { + if (env && !strcmp(env, "1")) + _ulog_channels = ULOG_KMSG; + else if (isatty(1)) + _ulog_channels = ULOG_STDIO; + else + _ulog_channels = ULOG_SYSLOG; + } + + if (_ulog_facility < 0) { + if (env && !strcmp(env, "1")) + _ulog_facility = LOG_DAEMON; + else if (isatty(1)) + _ulog_facility = LOG_USER; + else + _ulog_facility = LOG_DAEMON; + } + + if (_ulog_ident == NULL && _ulog_channels != ULOG_STDIO) + _ulog_ident = ulog_default_ident(); + + if (_ulog_channels & ULOG_SYSLOG) + openlog(_ulog_ident, 0, _ulog_facility); + + _ulog_initialized = 1; +} + +static void ulog_kmsg(int priority, const char *fmt, va_list ap) +{ + FILE *kmsg; + + if ((kmsg = fopen("/dev/kmsg", "w")) != NULL) { + fprintf(kmsg, "<%u>", priority); + + if (_ulog_ident) + fprintf(kmsg, "%s: ", _ulog_ident); + + vfprintf(kmsg, fmt, ap); + fclose(kmsg); + } +} + +static void ulog_stdio(int priority, const char *fmt, va_list ap) +{ + FILE *out = stderr; + + if (priority == LOG_INFO || priority == LOG_NOTICE) + out = stdout; + + if (_ulog_ident) + fprintf(out, "%s: ", _ulog_ident); + + vfprintf(out, fmt, ap); +} + +static void ulog_syslog(int priority, const char *fmt, va_list ap) +{ + vsyslog(priority, fmt, ap); +} + +void ulog_open(int channels, int facility, const char *ident) +{ + _ulog_channels = channels; + _ulog_facility = facility; + _ulog_ident = ident; +} + +void ulog_threshold(int threshold) +{ + _ulog_threshold = threshold; +} + +void ulog(int priority, const char *fmt, ...) +{ + va_list ap; + + if (priority > _ulog_threshold) + return; + + ulog_defaults(); + + if (_ulog_channels & ULOG_KMSG) + { + va_start(ap, fmt); + ulog_kmsg(priority, fmt, ap); + va_end(ap); + } + + if (_ulog_channels & ULOG_STDIO) + { + va_start(ap, fmt); + ulog_stdio(priority, fmt, ap); + va_end(ap); + } + + if (_ulog_channels & ULOG_SYSLOG) + { + va_start(ap, fmt); + ulog_syslog(priority, fmt, ap); + va_end(ap); + } +} diff --git a/ulog.h b/ulog.h new file mode 100644 index 0000000..4818b1a --- /dev/null +++ b/ulog.h @@ -0,0 +1,42 @@ +/* + * ulog - simple logging functions + * + * Copyright (C) 2015 Jo-Philipp Wich + * + * Permission to use, copy, modify, and/or distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + */ + +#ifndef __LIBUBOX_ULOG_H +#define __LIBUBOX_ULOG_H + +#include + +enum { + ULOG_KMSG = (1 << 0), + ULOG_SYSLOG = (1 << 1), + ULOG_STDIO = (1 << 2) +}; + +void ulog_open(int channels, int facility, const char *ident); +void ulog_close(void); + +void ulog_threshold(int threshold); + +void ulog(int priority, const char *fmt, ...); + +#define ULOG_INFO(fmt, ...) ulog(LOG_INFO, fmt, ## __VA_ARGS__) +#define ULOG_NOTE(fmt, ...) ulog(LOG_NOTICE, fmt, ## __VA_ARGS__) +#define ULOG_WARN(fmt, ...) ulog(LOG_WARNING, fmt, ## __VA_ARGS__) +#define ULOG_ERR(fmt, ...) ulog(LOG_ERR, fmt, ## __VA_ARGS__) + +#endif