1 files changed, 162 insertions, 0 deletions
diff --git a/src/cargs/cargs.h b/src/cargs/cargs.h
new file mode 100644
index 0000000..17cba0a
--- /dev/null
+++ b/src/cargs/cargs.h
@@ -0,0 +1,162 @@
+#pragma once
+
+/**
+ * This is a simple alternative cross-platform implementation of getopt, which
+ * is used to parse argument strings submitted to the executable (argc and argv
+ * which are received in the main function).
+ */
+
+#ifndef CAG_LIBRARY_H
+#define CAG_LIBRARY_H
+
+#include <stdbool.h>
+#include <stddef.h>
+#include <stdio.h>
+
+#if defined(_WIN32) || defined(__CYGWIN__)
+#define CAG_EXPORT __declspec(dllexport)
+#define CAG_IMPORT __declspec(dllimport)
+#elif __GNUC__ >= 4
+#define CAG_EXPORT __attribute__((visibility("default")))
+#define CAG_IMPORT __attribute__((visibility("default")))
+#else
+#define CAG_EXPORT
+#define CAG_IMPORT
+#endif
+
+#if defined(CAG_SHARED)
+#if defined(CAG_EXPORTS)
+#define CAG_PUBLIC CAG_EXPORT
+#else
+#define CAG_PUBLIC CAG_IMPORT
+#endif
+#else
+#define CAG_PUBLIC
+#endif
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * An option is used to describe a flag/argument option submitted when the
+ * program is run.
+ */
+typedef struct cag_option
+{
+  const char identifier;
+  const char *access_letters;
+  const char *access_name;
+  const char *value_name;
+  const char *description;
+} cag_option;
+
+/**
+ * A context is used to iterate over all options provided. It stores the parsing
+ * state.
+ */
+typedef struct cag_option_context
+{
+  const struct cag_option *options;
+  size_t option_count;
+  int argc;
+  char **argv;
+  int index;
+  int inner_index;
+  bool forced_end;
+  char identifier;
+  char *value;
+} cag_option_context;
+
+/**
+ * This is just a small macro which calculates the size of an array.
+ */
+#define CAG_ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]))
+
+/**
+ * @brief Prints all options to the terminal.
+ *
+ * This function prints all options to the terminal. This can be used to
+ * generate the output for a "--help" option.
+ *
+ * @param options The options which will be printed.
+ * @param option_count The option count which will be printed.
+ * @param destination The destination where the output will be printed.
+ */
+CAG_PUBLIC void cag_option_print(const cag_option *options, size_t option_count,
+  FILE *destination);
+
+/**
+ * @brief Prepare argument options context for parsing.
+ *
+ * This function prepares the context for iteration and initializes the context
+ * with the supplied options and arguments. After the context has been prepared,
+ * it can be used to fetch arguments from it.
+ *
+ * @param context The context which will be initialized.
+ * @param options The registered options which are available for the program.
+ * @param option_count The amount of options which are available for the
+ * program.
+ * @param argc The amount of arguments the user supplied in the main function.
+ * @param argv A pointer to the arguments of the main function.
+ */
+CAG_PUBLIC void cag_option_prepare(cag_option_context *context,
+  const cag_option *options, size_t option_count, int argc, char **argv);
+
+/**
+ * @brief Fetches an option from the argument list.
+ *
+ * This function fetches a single option from the argument list. The context
+ * will be moved to that item. Information can be extracted from the context
+ * after the item has been fetched.
+ * The arguments will be re-ordered, which means that non-option arguments will
+ * be moved to the end of the argument list. After all options have been
+ * fetched, all non-option arguments will be positioned after the index of
+ * the context.
+ *
+ * @param context The context from which we will fetch the option.
+ * @return Returns true if there was another option or false if the end is
+ * reached.
+ */
+CAG_PUBLIC bool cag_option_fetch(cag_option_context *context);
+
+/**
+ * @brief Gets the identifier of the option.
+ *
+ * This function gets the identifier of the option, which should be unique to
+ * this option and can be used to determine what kind of option this is.
+ *
+ * @param context The context from which the option was fetched.
+ * @return Returns the identifier of the option.
+ */
+CAG_PUBLIC char cag_option_get(const cag_option_context *context);
+
+/**
+ * @brief Gets the value from the option.
+ *
+ * This function gets the value from the option, if any. If the option does not
+ * contain a value, this function will return NULL.
+ *
+ * @param context The context from which the option was fetched.
+ * @return Returns a pointer to the value or NULL if there is no value.
+ */
+CAG_PUBLIC const char *cag_option_get_value(const cag_option_context *context);
+
+/**
+ * @brief Gets the current index of the context.
+ *
+ * This function gets the index within the argv arguments of the context. The
+ * context always points to the next item which it will inspect. This is
+ * particularly useful to inspect the original argument array, or to get
+ * non-option arguments after option fetching has finished.
+ *
+ * @param context The context from which the option was fetched.
+ * @return Returns the current index of the context.
+ */
+CAG_PUBLIC int cag_option_get_index(const cag_option_context *context);
+
+#ifdef __cplusplus
+} // extern "C"
+#endif
+
+#endif