X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=log.c;h=5d17955e7ebbd9ddb25a933b8faebac4192bb9fe;hp=8d292139343da0925e422850a75681abc6d4d17c;hb=43aa226daf2abe7af37d86379b4bf69efbc03f78;hpb=5899f3b7f62151dade30010370fb5d2bcdb93d3a

diff --git a/log.c b/log.c
index 8d2921393..5d17955e7 100644
--- a/log.c
+++ b/log.c
@@ -1,38 +1,439 @@
 /*-*- Mode: C; c-basic-offset: 8 -*-*/
 
-#ifdef HAVE_CONFIG_H
-#include <config.h>
-#endif
+/***
+  This file is part of systemd.
+
+  Copyright 2010 Lennart Poettering
+
+  systemd 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; either version 2 of the License, or
+  (at your option) any later version.
+
+  systemd 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 systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
 
 #include <stdarg.h>
 #include <stdio.h>
+#include <errno.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/socket.h>
+#include <sys/un.h>
 
 #include "log.h"
+#include "util.h"
+#include "macro.h"
+
+#define SYSLOG_TIMEOUT_USEC (5*USEC_PER_SEC)
+#define LOG_BUFFER_MAX 1024
+
+static LogTarget log_target = LOG_TARGET_CONSOLE;
+static int log_max_level = LOG_DEBUG;
+
+static int console_fd = STDERR_FILENO;
+static int syslog_fd = -1;
+static int kmsg_fd = -1;
+
+/* Akin to glibc's __abort_msg; which is private and we hance cannot
+ * use here. */
+static char *log_abort_msg = NULL;
+
+void log_close_console(void) {
+
+        if (console_fd < 0)
+                return;
+
+        if (getpid() == 1 || console_fd != STDERR_FILENO) {
+                close_nointr_nofail(console_fd);
+                console_fd = -1;
+        }
+}
+
+static int log_open_console(void) {
+
+        if (console_fd >= 0)
+                return 0;
+
+        if (getpid() == 1) {
+
+                if ((console_fd = open_terminal("/dev/console", O_WRONLY|O_NOCTTY|O_CLOEXEC)) < 0) {
+                        log_error("Failed to open /dev/console for logging: %s", strerror(-console_fd));
+                        return console_fd;
+                }
+
+                log_info("Succesfully opened /dev/console for logging.");
+        } else
+                console_fd = STDERR_FILENO;
+
+        return 0;
+}
+
+void log_close_kmsg(void) {
+
+        if (kmsg_fd < 0)
+                return;
+
+        close_nointr_nofail(kmsg_fd);
+        kmsg_fd = -1;
+}
+
+static int log_open_kmsg(void) {
+
+        if (kmsg_fd >= 0)
+                return 0;
+
+        if ((kmsg_fd = open("/dev/kmsg", O_WRONLY|O_NOCTTY|O_CLOEXEC)) < 0) {
+                log_info("Failed to open /dev/kmsg for logging: %s", strerror(errno));
+                return -errno;
+        }
+
+        log_info("Succesfully opened /dev/kmsg for logging.");
+
+        return 0;
+}
+
+void log_close_syslog(void) {
+
+        if (syslog_fd < 0)
+                return;
+
+        close_nointr_nofail(syslog_fd);
+        syslog_fd = -1;
+}
+
+static int log_open_syslog(void) {
+        union {
+                struct sockaddr sa;
+                struct sockaddr_un un;
+        } sa;
+        struct timeval tv;
+        int r;
+
+        if (syslog_fd >= 0)
+                return 0;
+
+        if ((syslog_fd = socket(AF_UNIX, SOCK_DGRAM|SOCK_CLOEXEC, 0)) < 0) {
+                r = -errno;
+                goto fail;
+        }
+
+        /* Make sure we don't block for more than 5s when talking to
+         * syslog */
+        timeval_store(&tv, SYSLOG_TIMEOUT_USEC);
+        if (setsockopt(syslog_fd, SOL_SOCKET, SO_SNDTIMEO, &tv, sizeof(tv)) < 0) {
+                r = -errno;
+                goto fail;
+        }
+
+        zero(sa);
+        sa.un.sun_family = AF_UNIX;
+        strncpy(sa.un.sun_path, "/dev/log", sizeof(sa.un.sun_path));
+
+        if (connect(syslog_fd, &sa.sa, sizeof(sa)) < 0) {
+                r = -errno;
+                goto fail;
+        }
+
+        log_info("Succesfully opened syslog for logging.");
+
+        return 0;
+
+fail:
+        log_close_syslog();
+        log_info("Failed to open syslog for logging: %s", strerror(-r));
+        return r;
+}
+
+int log_open(void) {
+        int r;
+
+        /* If we don't use the console we close it here, to not get
+         * killed by SAK. If we don't use syslog we close it here so
+         * that we are not confused by somebody deleting the socket in
+         * the fs. If we don't use /dev/kmsg we still keep it open,
+         * because there is no reason to close it. */
+
+        if (log_target == LOG_TARGET_SYSLOG_OR_KMSG ||
+            log_target == LOG_TARGET_SYSLOG)
+                if ((r = log_open_syslog()) >= 0) {
+                        log_close_console();
+                        return r;
+                }
+
+        if (log_target == LOG_TARGET_SYSLOG_OR_KMSG ||
+            log_target == LOG_TARGET_KMSG)
+                if ((r = log_open_kmsg()) >= 0) {
+                        log_close_syslog();
+                        log_close_console();
+                        return r;
+                }
+
+        log_close_syslog();
+        return log_open_console();
+}
+
+void log_set_target(LogTarget target) {
+        assert(target >= 0);
+        assert(target < _LOG_TARGET_MAX);
+
+        log_target = target;
+}
+
+void log_set_max_level(int level) {
+        assert((level & LOG_PRIMASK) == level);
+
+        log_max_level = level;
+}
+
+static int write_to_console(
+        int level,
+        const char*file,
+        int line,
+        const char *func,
+        const char *buffer) {
+
+        char location[64];
+        struct iovec iovec[5];
+        unsigned n = 0;
+        bool highlight;
+
+        if (console_fd < 0)
+                return 0;
+
+        snprintf(location, sizeof(location), "(%s:%u) ", file, line);
+        char_array_0(location);
+
+        highlight = LOG_PRI(level) <= LOG_ERR;
+
+        zero(iovec);
+        IOVEC_SET_STRING(iovec[n++], location);
+        if (highlight)
+                IOVEC_SET_STRING(iovec[n++], "\x1B[1;31m");
+        IOVEC_SET_STRING(iovec[n++], buffer);
+        if (highlight)
+                IOVEC_SET_STRING(iovec[n++], "\x1B[0m");
+        IOVEC_SET_STRING(iovec[n++], "\n");
+
+        if (writev(console_fd, iovec, n) < 0)
+                return -errno;
+
+        return 1;
+}
+
+static int write_to_syslog(
+        int level,
+        const char*file,
+        int line,
+        const char *func,
+        const char *buffer) {
+
+        char header_priority[16], header_time[64], header_pid[16];
+        struct iovec iovec[5];
+        struct msghdr msghdr;
+        time_t t;
+        struct tm *tm;
+
+        if (syslog_fd < 0)
+                return 0;
+
+        snprintf(header_priority, sizeof(header_priority), "<%i>", LOG_MAKEPRI(LOG_DAEMON, LOG_PRI(level)));
+        char_array_0(header_priority);
+
+        t = (time_t) (now(CLOCK_REALTIME) / USEC_PER_SEC);
+        if (!(tm = localtime(&t)))
+                return -EINVAL;
+
+        if (strftime(header_time, sizeof(header_time), "%h %e %T ", tm) <= 0)
+                return -EINVAL;
+
+        snprintf(header_pid, sizeof(header_pid), "[%llu]: ", (unsigned long long) getpid());
+        char_array_0(header_pid);
+
+        zero(iovec);
+        IOVEC_SET_STRING(iovec[0], header_priority);
+        IOVEC_SET_STRING(iovec[1], header_time);
+        IOVEC_SET_STRING(iovec[2], __progname);
+        IOVEC_SET_STRING(iovec[3], header_pid);
+        IOVEC_SET_STRING(iovec[4], buffer);
+
+        zero(msghdr);
+        msghdr.msg_iov = iovec;
+        msghdr.msg_iovlen = ELEMENTSOF(iovec);
+
+        if (sendmsg(syslog_fd, &msghdr, 0) < 0)
+                return -errno;
+
+        return 1;
+}
+
+static int write_to_kmsg(
+        int level,
+        const char*file,
+        int line,
+        const char *func,
+        const char *buffer) {
 
-void log_meta(
+        char header_priority[16], header_pid[16];
+        struct iovec iovec[5];
+
+        if (kmsg_fd < 0)
+                return 0;
+
+        snprintf(header_priority, sizeof(header_priority), "<%i>", LOG_PRI(level));
+        char_array_0(header_priority);
+
+        snprintf(header_pid, sizeof(header_pid), "[%llu]: ", (unsigned long long) getpid());
+        char_array_0(header_pid);
+
+        zero(iovec);
+        IOVEC_SET_STRING(iovec[0], header_priority);
+        IOVEC_SET_STRING(iovec[1], __progname);
+        IOVEC_SET_STRING(iovec[2], header_pid);
+        IOVEC_SET_STRING(iovec[3], buffer);
+        IOVEC_SET_STRING(iovec[4], "\n");
+
+        if (writev(kmsg_fd, iovec, ELEMENTSOF(iovec)) < 0)
+                return -errno;
+
+        return 1;
+}
+
+static int log_dispatch(
+        int level,
+        const char*file,
+        int line,
+        const char *func,
+        const char *buffer) {
+
+        int r;
+
+        if (log_target == LOG_TARGET_SYSLOG_OR_KMSG ||
+            log_target == LOG_TARGET_SYSLOG) {
+
+                if ((r = write_to_syslog(level, file, line, func, buffer)) < 0) {
+                        log_close_syslog();
+                        log_open_kmsg();
+                } else if (r > 0)
+                        return r;
+        }
+
+        if (log_target == LOG_TARGET_SYSLOG_OR_KMSG ||
+            log_target == LOG_TARGET_KMSG) {
+
+                if ((r = write_to_kmsg(level, file, line, func, buffer)) < 0) {
+                        log_close_kmsg();
+                        log_open_console();
+                } else if (r > 0)
+                        return r;
+        }
+
+        return write_to_console(level, file, line, func, buffer);
+}
+
+int log_meta(
         int level,
         const char*file,
         int line,
         const char *func,
         const char *format, ...) {
 
-        const char *prefix, *suffix;
+        char buffer[LOG_BUFFER_MAX];
+        int saved_errno, r;
         va_list ap;
 
-        if (LOG_PRI(level) <= LOG_ERR) {
-                prefix = "\x1B[1;31m";
-                suffix = "\x1B[0m";
-        } else {
-                prefix = "";
-                suffix = "";
-        }
+        if (_likely(LOG_PRI(level) > log_max_level))
+                return 0;
+
+        saved_errno = errno;
 
         va_start(ap, format);
+        vsnprintf(buffer, sizeof(buffer), format, ap);
+        va_end(ap);
+
+        char_array_0(buffer);
 
-        fprintf(stderr, "(%s:%u) %s", file, line, prefix);
-        vfprintf(stderr, format, ap);
-        fprintf(stderr, "%s\n", suffix);
+        r = log_dispatch(level, file, line, func, buffer);
+        errno = saved_errno;
 
+        return r;
+}
+
+void log_assert(
+        const char*file,
+        int line,
+        const char *func,
+        const char *format, ...) {
+
+        static char buffer[LOG_BUFFER_MAX];
+        int saved_errno = errno;
+        va_list ap;
+
+        va_start(ap, format);
+        vsnprintf(buffer, sizeof(buffer), format, ap);
         va_end(ap);
 
+        char_array_0(buffer);
+        log_abort_msg = buffer;
+
+        log_dispatch(LOG_CRIT, file, line, func, buffer);
+        abort();
+
+        /* If the user chose to ignore this SIGABRT, we are happy to go on, as if nothing happened. */
+        errno = saved_errno;
 }
+
+int log_set_target_from_string(const char *e) {
+        LogTarget t;
+
+        if ((t = log_target_from_string(e)) < 0)
+                return -EINVAL;
+
+        log_set_target(t);
+        return 0;
+}
+
+int log_set_max_level_from_string(const char *e) {
+        int t;
+
+        if ((t = log_level_from_string(e)) < 0)
+                return -EINVAL;
+
+        log_set_max_level(t);
+        return 0;
+}
+
+void log_parse_environment(void) {
+        const char *e;
+
+        if ((e = getenv("SYSTEMD_LOG_TARGET")))
+                if (log_set_target_from_string(e) < 0)
+                        log_warning("Failed to parse log target %s. Ignoring.", e);
+
+        if ((e = getenv("SYSTEMD_LOG_LEVEL")))
+                if (log_set_max_level_from_string(e) < 0)
+                        log_warning("Failed to parse log level %s. Ignoring.", e);
+}
+
+LogTarget log_get_target(void) {
+        return log_target;
+}
+
+int log_get_max_level(void) {
+        return log_max_level;
+}
+
+static const char *const log_target_table[] = {
+        [LOG_TARGET_CONSOLE] = "console",
+        [LOG_TARGET_SYSLOG] = "syslog",
+        [LOG_TARGET_KMSG] = "kmsg",
+        [LOG_TARGET_SYSLOG_OR_KMSG] = "syslog-or-kmsg",
+};
+
+DEFINE_STRING_TABLE_LOOKUP(log_target, LogTarget);