1 files changed, 168 insertions, 0 deletions
diff --git a/lib/logging.c b/lib/logging.c
new file mode 100644
index 0000000..6dd0731
--- /dev/null
+++ b/lib/logging.c
@@ -0,0 +1,168 @@
+/*
+   Provides a log file to ease tracing the program.
+
+   Copyright (C) 2006-2023
+   Free Software Foundation, Inc.
+
+   Written by:
+   Roland Illig <roland.illig@gmx.de>, 2006
+   Slava Zanko <slavazanko@gmail.com>, 2009, 2011
+
+   This file is part of the Midnight Commander.
+
+   The Midnight Commander 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 3 of the License,
+   or (at your option) any later version.
+
+   The Midnight Commander 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 <http://www.gnu.org/licenses/>.
+ */
+
+/** \file logging.c
+ *  \brief Source: provides a log file to ease tracing the program
+ */
+
+#include <config.h>
+
+#include <stdarg.h>
+#include <stdio.h>
+
+#include "lib/global.h"
+#include "lib/mcconfig.h"
+#include "lib/fileloc.h"
+
+#include "logging.h"
+
+/*** global variables ****************************************************************************/
+
+/*** file scope macro definitions ****************************************************************/
+
+#define CONFIG_GROUP_NAME "Development"
+#define CONFIG_KEY_NAME "logging"
+#define CONFIG_KEY_NAME_FILE "logfile"
+
+/*** file scope type declarations ****************************************************************/
+
+/*** forward declarations (file scope functions) *************************************************/
+
+/*** file scope variables ************************************************************************/
+
+static gboolean logging_initialized = FALSE;
+static gboolean logging_enabled = FALSE;
+
+/* --------------------------------------------------------------------------------------------- */
+/*** file scope functions ************************************************************************/
+/* --------------------------------------------------------------------------------------------- */
+
+static gboolean
+is_logging_enabled_from_env (void)
+{
+    const char *env_is_enabled;
+
+    env_is_enabled = g_getenv ("MC_LOG_ENABLE");
+    if (env_is_enabled == NULL)
+        return FALSE;
+
+    logging_enabled = (*env_is_enabled == '1' || g_ascii_strcasecmp (env_is_enabled, "true") == 0);
+    logging_initialized = TRUE;
+    return TRUE;
+}
+
+/* --------------------------------------------------------------------------------------------- */
+
+static gboolean
+is_logging_enabled (void)
+{
+
+    if (logging_initialized)
+        return logging_enabled;
+
+    if (is_logging_enabled_from_env ())
+        return logging_enabled;
+
+    logging_enabled =
+        mc_config_get_bool (mc_global.main_config, CONFIG_GROUP_NAME, CONFIG_KEY_NAME, FALSE);
+    logging_initialized = TRUE;
+
+    return logging_enabled;
+}
+
+/* --------------------------------------------------------------------------------------------- */
+
+static char *
+get_log_filename (void)
+{
+    const char *env_filename;
+
+    env_filename = g_getenv ("MC_LOG_FILE");
+    if (env_filename != NULL)
+        return g_strdup (env_filename);
+
+    if (mc_config_has_param (mc_global.main_config, CONFIG_GROUP_NAME, CONFIG_KEY_NAME_FILE))
+        return mc_config_get_string (mc_global.main_config, CONFIG_GROUP_NAME, CONFIG_KEY_NAME_FILE,
+                                     NULL);
+
+    return mc_config_get_full_path ("mc.log");
+}
+
+/* --------------------------------------------------------------------------------------------- */
+
+static void
+G_GNUC_PRINTF (1, 0)
+mc_va_log (const char *fmt, va_list args)
+{
+    char *logfilename;
+
+    logfilename = get_log_filename ();
+
+    if (logfilename != NULL)
+    {
+        FILE *f;
+
+        f = fopen (logfilename, "a");
+        if (f != NULL)
+        {
+            (void) vfprintf (f, fmt, args);
+            (void) fclose (f);
+        }
+        g_free (logfilename);
+    }
+
+}
+
+/* --------------------------------------------------------------------------------------------- */
+/*** public functions ****************************************************************************/
+/* --------------------------------------------------------------------------------------------- */
+
+void
+mc_log (const char *fmt, ...)
+{
+    va_list args;
+
+    if (!is_logging_enabled ())
+        return;
+
+    va_start (args, fmt);
+    mc_va_log (fmt, args);
+    va_end (args);
+}
+
+/* --------------------------------------------------------------------------------------------- */
+
+void
+mc_always_log (const char *fmt, ...)
+{
+    va_list args;
+
+    va_start (args, fmt);
+    mc_va_log (fmt, args);
+    va_end (args);
+}
+
+/* --------------------------------------------------------------------------------------------- */