amxc_rbuffer.h

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#if !defined(__AMXC_RBUFFER_H__)
#define __AMXC_RBUFFER_H__
 
#ifdef __cplusplus
extern "C"
{
#endif
 
#include <unistd.h>
 
#include <amxc/amxc_common.h>
#include <amxc/amxc_array.h>
 
typedef struct _amxc_rbuffer {
    char* buffer_start;      
    char* buffer_end;        
    char* read_pos;          
    char* write_pos;         
} amxc_rbuffer_t;
 
int amxc_rbuffer_new(amxc_rbuffer_t** rb, const size_t size);
 
void amxc_rbuffer_delete(amxc_rbuffer_t** rb);
 
int amxc_rbuffer_init(amxc_rbuffer_t* const rb, const size_t size);
 
void amxc_rbuffer_clean(amxc_rbuffer_t* const rb);
 
int amxc_rbuffer_grow(amxc_rbuffer_t* const rb, const size_t size);
 
int amxc_rbuffer_shrink(amxc_rbuffer_t* const rb, const size_t size);
 
ssize_t amxc_rbuffer_read(amxc_rbuffer_t* const rb,
                          char* const buf,
                          size_t count);
 
ssize_t amxc_rbuffer_write(amxc_rbuffer_t* const rb,
                           const char* const buf,
                           const size_t count);
 
size_t amxc_rbuffer_size(const amxc_rbuffer_t* const rb);
 
AMXC_INLINE
size_t amxc_rbuffer_capacity(const amxc_rbuffer_t* const rb) {
    return rb != NULL ? rb->buffer_end - rb->buffer_start : 0;
}
 
AMXC_INLINE
bool amxc_rbuffer_is_empty(const amxc_rbuffer_t* const rb) {
    return rb != NULL ? (rb->read_pos == rb->write_pos) : true;
}
 
#ifdef __cplusplus
}
#endif
 
#endif // __AMX_RBUFFER_H__