logging?

src/logging.c

@@ -0,0 +1,63 @@
+/*
+ * boxes - Command line filter to draw/remove ASCII boxes around text
+ * Copyright (c) 1999-2023 Thomas Jensen and the boxes contributors
+ *
+ * This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public
+ * License, version 3, as published by the Free Software Foundation.
+ * This program 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 this program.
+ * If not, see <https://www.gnu.org/licenses/>.
+ *
+* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
+ */
+
+/*
+ * Simple makeshift log facility, mostly used for handling debug output.
+ */
+
+#include <stdarg.h>
+#include "tools.h"
+#include "logging.h"
+
+log_level_t current_log_level = INFO;
+
+char *log_level_name[] = {
+    "TRACE", "DEBUG", "INFO", "WARN", "ERROR"
+};
+
+
+void log(log_level_t log_level, const char *module, const char *format, ...)
+{
+    char *s = (char *) malloc(512);
+    va_list va;
+    va_start(va, format);
+    vsprintf(s, format, va);
+    va_end(va);
+
+    switch(log_level) {
+        case TRACE:
+        case DBG:
+            if (log_level >= current_log_level) {
+                bx_fprintf(stderr, "%5s %s: %s\n", log_level_name[log_level], module, s);
+            }
+            break;
+
+        case INFO:
+            if (log_level >= current_log_level) {
+                bx_fprintf(stdout, s);
+            }
+            break;
+
+        case WARN:
+        case ERROR:
+            if (log_level >= current_log_level) {
+                bx_fprintf(stderr, "%5s: %s\n", log_level_name[log_level], s);
+            }
+            break;
+    }
+}
+
+
+/* vim: set cindent sw=4: */

src/logging.h

@@ -0,0 +1,61 @@
+/*
+ * boxes - Command line filter to draw/remove ASCII boxes around text
+ * Copyright (c) 1999-2023 Thomas Jensen and the boxes contributors
+ *
+ * This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public
+ * License, version 3, as published by the Free Software Foundation.
+ * This program 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 this program.
+ * If not, see <https://www.gnu.org/licenses/>.
+ *
+* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
+ */
+
+/*
+ * Simple makeshift log facility.
+ */
+
+#ifndef LOGGING_H
+#define LOGGING_H
+
+
+typedef enum _log_level_t {
+    /** the finest log level */
+    TRACE,
+
+    /** a debug message, should be called `DEBUG` */
+    DBG,
+
+    /** normal informational message */
+    INFO,
+
+    /** a warning message, which should not happen, but can be tolerated */
+    WARN,
+
+    /** an error message, normally this will also lead to abnormal program termination */
+    ERROR
+} log_level_t;
+
+
+/** currently active log level, determine whether a message gets printed */
+extern log_level_t current_log_level;
+
+
+/** log level names for printing */
+extern char *log_level_name[];
+
+
+/**
+ * Print a log message. Log messages of level INFO will be printed in `stdout`, others on `stderr`.
+ * @param log_level the log level
+ * @param module the module name as per `__FILE__`
+ * @param format format string for the mesage, followed by the placeholder arguments
+ */
+void log(log_level_t log_level, const char *module, const char *format, ...);
+
+
+#endif
+
+/* vim: set cindent sw=4: */