ruby/yarp/util/yp_string.h

#ifndef YARP_STRING_H
#define YARP_STRING_H

#include "yarp/defines.h"

#include <stddef.h>
#include <stdlib.h>
#include <string.h>

// This struct represents a string value.
typedef struct {
    enum { YP_STRING_SHARED, YP_STRING_OWNED, YP_STRING_CONSTANT } type;

    union {
        struct {
            const char *start;
            const char *end;
        } shared;

        struct {
            char *source;
            size_t length;
        } owned;

        struct {
            const char *source;
            size_t length;
        } constant;
    } as;
} yp_string_t;

// Initialize a shared string that is based on initial input.
void yp_string_shared_init(yp_string_t *string, const char *start, const char *end);

// Initialize an owned string that is responsible for freeing allocated memory.
void yp_string_owned_init(yp_string_t *string, char *source, size_t length);

// Initialize a constant string that doesn't own its memory source.
void yp_string_constant_init(yp_string_t *string, const char *source, size_t length);

// Returns the memory size associated with the string.
size_t yp_string_memsize(const yp_string_t *string);

// Ensure the string is owned. If it is not, then reinitialize it as owned and
// copy over the previous source.
void yp_string_ensure_owned(yp_string_t *string);

// Returns the length associated with the string.
YP_EXPORTED_FUNCTION size_t yp_string_length(const yp_string_t *string);

// Returns the start pointer associated with the string.
YP_EXPORTED_FUNCTION const char * yp_string_source(const yp_string_t *string);

// Free the associated memory of the given string.
YP_EXPORTED_FUNCTION void yp_string_free(yp_string_t *string);

#endif // YARP_STRING_H