Add missing common files

src/common.c

@@ -0,0 +1,83 @@
+// MIT License
+//
+// Copyright (c) 2022 Marc Ransome
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in all
+// copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+// SOFTWARE.
+
+#include "common.h"
+#include <stdio.h>
+
+static const char *
+flog_error_map[] = {
+  [FLOG_ERROR_NONE]   = "none",
+  [FLOG_ERROR_ALLOC]  = "allocation failed",
+  [FLOG_ERROR_APPEND] = "unable to append log message to file",
+  [FLOG_ERROR_LVL]    = "unknown log level",
+  [FLOG_ERROR_MSG]    = "message string required",
+  [FLOG_ERROR_SUBSYS] = "category option requires subsystem option to be set",
+  [FLOG_ERROR_OPTS]   = "invalid options",
+};
+
+const char *
+flog_error_string(FlogError error) {
+  return flog_error_map[error];
+}
+
+void
+flog_print_error(FlogError error) {
+    fprintf(stderr, "%s: %s\n", PROGRAM_NAME, flog_error_string(error));
+}
+
+void
+flog_print_error_string(const char *error) {
+    fprintf(stderr, "%s: %s", PROGRAM_NAME, error);
+}
+
+void
+flog_usage(void) {
+    printf(
+        "%s %s\n"
+        "\n"
+        "Usage:\n"
+        "    %s [options] message\n"
+        "\n"
+        "Help Options:\n"
+        "    -h, --help       Show this help message\n"
+        "    -v, --version    Print the version string\n"
+        "\n"
+        "Application Options:\n"
+        "    -s, --subsystem <name>   Specify a subsystem name\n"
+        "    -c, --category <name>    Specify a category name (requires subsystem option)\n"
+        "    -l, --level <level>      Specify the log level ('default' if not provided)\n"
+        "    -a, --append <path>      Append the log message to a file (creating it if necessary)\n"
+        "    -p, --private            Mark the log message as private\n"
+        "\n"
+        "Log Levels:\n"
+        "    default, info, debug, error, fault\n"
+        "\n",
+        PROGRAM_NAME,
+        PROGRAM_VERSION,
+        PROGRAM_NAME
+    );
+}
+
+void
+flog_version(void) {
+    printf("%s %s\n", PROGRAM_NAME, PROGRAM_VERSION);
+}

src/common.h

@@ -0,0 +1,75 @@
+// MIT License
+//
+// Copyright (c) 2022 Marc Ransome
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in all
+// copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+// SOFTWARE.
+
+#ifndef FLOG_COMMON_H
+#define FLOG_COMMON_H
+
+/*! \file common.h
+ *
+ *  Constants, helper functions, and error handling types for common operations.
+ */
+
+#define PROGRAM_NAME "flog"
+#define PROGRAM_VERSION "1.4.0"
+
+/*! \brief An enumerated type representing error conditions. */
+typedef enum FlogErrorData {
+    FLOG_ERROR_NONE,
+    FLOG_ERROR_ALLOC,
+    FLOG_ERROR_APPEND,
+    FLOG_ERROR_LVL,
+    FLOG_ERROR_MSG,
+    FLOG_ERROR_OPTS,
+    FLOG_ERROR_SUBSYS,
+} FlogError;
+
+/*! \brief Print usage information to stdout stream. */
+void flog_usage(void);
+
+/*! \brief Print version string to stdout stream. */
+void flog_version(void);
+
+/*! \brief Return a string representation of an error condition.
+ *
+ * \param[in] error A \c FlogError enumeration variant
+ *
+ * \return A pointer to a null-terminated string describing the error condition
+ */
+const char * flog_get_error_string(FlogError error);
+
+/*! \brief Print a formatted error message representation of the error condition.
+ *
+ * \param[in] error A \c FlogError enumeration variant representing the error condition
+ *
+ * \return void
+ */
+void flog_print_error(FlogError error);
+
+/*! \brief Print a formatted error message string.
+ *
+ * \param[out] error A null-terminated string describing the error condition.
+ *
+ * \return void
+ */
+void flog_print_error_string(const char *error);
+
+#endif //FLOG_COMMON_H