feat: First stable release

util.c

@@ -0,0 +1,84 @@
+/*
+ * util.c
+ *  Common utils.
+ *
+ * Copyright (c) 2022
+ *     Tom MTT. <tom@heimdall.pm>
+ *
+ * This file is licensed under the 3-Clause BSD License.
+ * You should have received a copy of the 3-Clause BSD License
+ * along with this program. If not, see
+ * <https://basedwa.re/tmtt/feuille/src/branch/main/LICENSE>.
+ */
+
+#define _DEFAULT_SOURCE
+
+#include "util.h"
+
+#include <stdarg.h>   /* for va_end, va_list, va_start                     */
+#include <stdio.h>    /* for snprintf, vsnprintf, vfprintf, BUFSIZ, stderr */
+#include <stdlib.h>   /* for exit                                          */
+#include <syslog.h>   /* for syslog, LOG_DEBUG, LOG_ERR                    */
+#include <unistd.h>   /* for getpid                                        */
+
+#include "feuille.h"  /* for Settings, settings                            */
+
+/* reuse that buffer for syslogs */
+char syslog_buffer[BUFSIZ];
+
+/**
+ * Die with an error message.
+ *   exit_code: the exit code to be used.
+ *   string: the string to be displayed. Printf format is supported.
+ */
+void die(int exit_code, char *string, ...)
+{
+    va_list ap;
+
+    va_start(ap, string);
+    vfprintf(stderr, string, ap);
+    va_end(ap);
+
+    exit(exit_code);
+}
+
+/**
+ * Send an error message to syslog.
+ *   string: the string to be displayed. Printf format is supported.
+ */
+void error(char *string, ...)
+{
+    va_list ap;
+    va_start(ap, string);
+
+    /* prepend the PID of the current thread */
+    int length = snprintf(syslog_buffer, sizeof(syslog_buffer), "ERROR[%d]: ", getpid());
+
+    /* send the string to syslog */
+    vsnprintf(syslog_buffer + length, sizeof(syslog_buffer) - length, string, ap);
+    syslog(LOG_ERR, "%s", syslog_buffer);
+
+    va_end(ap);
+}
+
+/**
+ * Send a message to syslog if in verbose mode.
+ *   string: the string to be displayed. Printf format is supported.
+ */
+void verbose(int level, char *string, ...)
+{
+    if (settings.verbose < level)
+        return;
+
+    va_list ap;
+    va_start(ap, string);
+
+    /* prepend the PID of the current thread */
+    int length = snprintf(syslog_buffer, sizeof(syslog_buffer), "DEBUG%d[%d]: ", level, getpid());
+
+    /* send the string to syslog */
+    vsnprintf(syslog_buffer + length, sizeof(syslog_buffer) - length, string, ap);
+    syslog(LOG_DEBUG, "%s", syslog_buffer);
+
+    va_end(ap);
+}