Version 1.08 with public source code release.

src/main/util/options.h

@@ -0,0 +1,170 @@
+#ifndef UTIL_OPTIONS_H
+#define UTIL_OPTIONS_H
+
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdio.h>
+
+/**
+ * Value types support by option values
+ */
+enum util_options_type {
+    UTIL_OPTIONS_TYPE_INT,
+    UTIL_OPTIONS_TYPE_DOUBLE,
+    UTIL_OPTIONS_TYPE_STR,
+    UTIL_OPTIONS_TYPE_BOOL,
+    UTIL_OPTIONS_TYPE_BIN,
+};
+
+/**
+ * Single option definition element. Use this to define possible option
+ * key-value tuples to parse from an argument list
+ */
+struct util_options_def {
+    const char* name;
+    const char* description;
+    const char param;
+    enum util_options_type type;
+    union {
+        int i;
+        double d;
+        const char* str;
+        bool b;
+        struct {
+            const uint8_t* data;
+            size_t len;
+        } bin;
+    } default_value;
+};
+
+/**
+ * Option definitions. A list of key-value elements defining option values
+ * as well as usage information for the application
+ */
+struct util_options_defs {
+    const char* usage_header;
+    char usage_param;
+    const struct util_options_def* defs;
+    uint32_t ndefs;
+};
+
+/**
+ * A single option value as part of the key-value tuple
+ */
+struct util_options_value {
+    bool avail;
+    union {
+        int i;
+        double d;
+        char* str;
+        bool b;
+        struct {
+            uint8_t* data;
+            size_t len;
+        } bin;
+    } value;
+};
+
+/**
+ * Parsed option values based on an options definition
+ */
+struct util_options_opts {
+    const struct util_options_defs* defs;
+    struct util_options_value* values;
+    uint32_t entries;
+};
+
+/**
+ * Initialize the options module by passing the arguments from main on
+ *
+ * Make sure to call this as early as possible when entering main and before
+ * any other calls of this module are invoked
+ *
+ * @param argc Argc from main
+ * @param argv Argv from main
+ */
+void util_options_init(int argc, char** argv);
+
+/**
+ * Get options from the initial argument list
+ *
+ * @param option_defs A list of option definitions. The arguments are parsed
+ *        using this list. If NULL, usage information with the definition
+ *        is printed and this call also returns NULL.
+ * @return A list of parsed options based on the specified definitions or
+ *         NULL if usage information was printed.
+ */
+struct util_options_opts* util_options_get(
+    const struct util_options_defs* option_defs);
+
+/**
+ * Get an integer value from an options list
+ *
+ * @param opts Parsed options list received from util_options_get
+ * @param name Name of the options key
+ * @return Value of the options key converted to an integer value. If the type
+ *         of the options key is not matching, 0 is returned
+ */
+int util_options_get_int(const struct util_options_opts* opts,
+    const char* name);
+
+/**
+ * Get a double value from an options list
+ *
+ * @param opts Parsed options list received from util_options_get
+ * @param name Name of the options key
+ * @return Value of the options key converted to a double value. If the type
+ *         of the options key is not matching, 0 is returned
+ */
+double util_options_get_double(const struct util_options_opts* opts, const char* name);
+
+/**
+ * Get a string from an options list
+ *
+ * @param opts Parsed options list received from util_options_get
+ * @param name Name of the options key
+ * @return Value of the options key converted to a string. If the type
+ *         of the options key is not matching, NULL is returned
+ */
+const char* util_options_get_str(const struct util_options_opts* opts,
+    const char* name);
+
+/**
+ * Get a bool value from an options list
+ *
+ * @param opts Parsed options list received from util_options_get
+ * @param name Name of the options key
+ * @return Value of the options key converted to a bool value. If the type
+ *         of the options key is not matching, false is returned
+ */
+bool util_options_get_bool(const struct util_options_opts* opts,
+    const char* name);
+
+/**
+ * Get binary data from an options list
+ *
+ * @param opts Parsed options list received from util_options_get
+ * @param name Name of the options key
+ * @param length Pointer to return the length of the binary data to
+ *         (set to NULL if not required)
+ * @return Value of the options key converted to a binary array. If the type
+ *         of the options key is not matching, NULL is returned
+ */
+const uint8_t* util_options_get_bin(const struct util_options_opts* opts,
+    const char* name, size_t* length);
+
+/**
+ * Print usage information
+ *
+ * @param option_defs A list of option definitions.
+ */
+void util_options_print_usage(const struct util_options_defs* opts);
+
+/**
+ * Free an options list
+ *
+ * @param opts Options list to free
+ */
+void util_options_free(struct util_options_opts* opts);
+
+#endif