libply: Add support for syslog

Sometimes plymouth is used along-side other programs. Those
programs may use syslog for logging, and so it would be useful
if plymouth had the ability to use syslog, too. Then message
ordering would be more coherent.

This commit adds such support by adding plymouth.debug=syslog
to the kernel command line.

diff --git a/src/libply/ply-logger.c b/src/libply/ply-logger.c
index 749c9da583f297fc20e72258cc7a1fb4111f5ad1..e83bd1d4b4a11934f32d3350ad2cf93baebf1499 100644 (file)
--- a/src/libply/ply-logger.c
+++ b/src/libply/ply-logger.c
@@ -73,6 +73,9 @@ struct _ply_logger
 
         uint32_t                  is_enabled : 1;
         uint32_t                  tracing_is_enabled : 1;
+        uint32_t                  syslog_is_enabled : 1;
+        uint32_t                  is_error_default : 1;
+        uint32_t                  is_default : 1;
 };
 
 static bool ply_text_is_loggable (const char *string,
@@ -117,6 +120,13 @@ ply_logger_write_exception (ply_logger_t *logger,
 
         assert (message != NULL);
 
+        if (logger->syslog_is_enabled) {
+                syslog (LOG_WARNING,
+                        "%.*s",
+                        message,
+                        number_of_bytes);
+        }
+
         ply_logger_write (logger, message, number_of_bytes, false);
         free (message);
 }
@@ -155,6 +165,23 @@ ply_logger_flush_buffer (ply_logger_t *logger)
         if (logger->buffer_size == 0)
                 return true;
 
+        if (logger->syslog_is_enabled) {
+                int log_priority;
+
+                if (logger->tracing_is_enabled) {
+                        log_priority = LOG_DEBUG;
+                } else if (logger->is_default) {
+                        log_priority = LOG_INFO;
+                } else if (logger->is_error_default) {
+                        log_priority = LOG_WARNING;
+                }
+
+                syslog (log_priority,
+                        "%.*s",
+                        logger->buffer_size,
+                        logger->buffer);
+        }
+
         if (!ply_logger_write (logger, logger->buffer, logger->buffer_size, true))
                 return false;
 
@@ -252,6 +279,7 @@ ply_logger_get_default (void)
         if (logger == NULL) {
                 logger = ply_logger_new ();
                 ply_logger_set_output_fd (logger, STDOUT_FILENO);
+                logger->is_default = true;
         }
 
         return logger;
@@ -267,6 +295,7 @@ ply_logger_get_error_default (void)
                 ply_logger_set_output_fd (logger, STDERR_FILENO);
                 ply_logger_set_flush_policy (logger,
                                              PLY_LOGGER_FLUSH_POLICY_EVERY_TIME);
+                logger->is_error_default = true;
         }
 
         return logger;
@@ -304,6 +333,10 @@ ply_logger_free (ply_logger_t *logger)
                 close (logger->output_fd);
         }
 
+        if (logger->syslog_is_enabled) {
+                ply_logger_close_syslog (logger);
+        }
+
         ply_logger_free_filters (logger);
 
         free (logger->filename);
@@ -358,6 +391,18 @@ ply_logger_close_file (ply_logger_t *logger)
         ply_logger_set_output_fd (logger, -1);
 }
 
+void
+ply_logger_open_syslog (ply_logger_t *logger)
+{
+        openlog (NULL, 0, LOG_DAEMON);
+}
+
+void
+ply_logger_close_syslog (ply_logger_t *logger)
+{
+        closelog ();
+}
+
 void
 ply_logger_set_output_fd (ply_logger_t *logger,
                           int           fd)

diff --git a/src/libply/ply-logger.h b/src/libply/ply-logger.h
index 8d8ee87194445fbe8a9aa9fe1c8c70b759b5ffdf..768a541d4923bb78d3ed6a52455570a19506ede3 100644 (file)
--- a/src/libply/ply-logger.h
+++ b/src/libply/ply-logger.h
@@ -49,6 +49,8 @@ void ply_logger_free (ply_logger_t *logger);
 bool ply_logger_open_file (ply_logger_t *logger,
                            const char   *filename);
 void ply_logger_close_file (ply_logger_t *logger);
+bool ply_logger_open_syslog (ply_logger_t *logger);
+void ply_logger_close_syslog (ply_logger_t *logger);
 void ply_logger_set_output_fd (ply_logger_t *logger,
                                int           fd);
 int ply_logger_get_output_fd (ply_logger_t *logger);

diff --git a/src/main.c b/src/main.c
index daf25243e4c276651410434f762c22a887d60bd2..ff700c3d53c9965d416ab4c3e0358b44e1e3ba27 100644 (file)
--- a/src/main.c
+++ b/src/main.c
@@ -1857,6 +1857,8 @@ static void
 check_verbosity (state_t *state)
 {
         char *stream;
+        char *syslog;
+        bool found_output_target = false;
 
         ply_trace ("checking if tracing should be enabled");
 
@@ -1906,7 +1908,18 @@ check_verbosity (state_t *state)
 
                         free (file);
                 }
-        } else {
+
+                found_output_target = true;
+        }
+
+        syslog = ply_kernel_command_line_get_key_value ("plymouth.debug=syslog");
+
+        if (syslog != NULL) {
+                ply_logger_open_syslog (ply_logger_get_error_default ());
+                found_output_target = true;
+        }
+
+        if (!found_output_target) {
                 ply_trace ("tracing shouldn't be enabled!");
         }