add command-line arguments

1 files changed, 162 insertions, 0 deletions

diff --git a/libs/cargs/include/cargs.h b/libs/cargs/include/cargs.h
new file mode 100644
index 0000000..17cba0a
--- /dev/null
+++ b/libs/cargs/include/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