str_buffer.c

#include "str_buffer.h"
#include <stdlib.h>
#include <string.h>
#include <stdint.h>

#ifdef S_SPLINT_S
typedef int8_t char;
typedef uint16_t int;
#endif

str_buffer_t* str_buffer_init( int len )
{
    str_buffer_t* self = malloc( sizeof( str_buffer_t ) );
    if( !self ){ printf("str_buffer malloc failed\n"); return NULL; }

	self->length = len;
	self->contents = malloc(sizeof(char) * len+1);
	if( !self->contents ){ printf("str_buffer contents!\n"); return NULL; }

	for( int i=0; i<(len+1); i++ ){ self->contents[i] = '\0'; }

	// empty when read == write ix
	self->ix_read = 0;
	self->ix_write = 0;
	self->count = 0;

	return self;
}

void str_buffer_deinit( str_buffer_t* buf )
{
	free( buf->contents ); buf->contents = NULL;
    free( buf ); buf = NULL;
}

void str_buffer_enqueue(str_buffer_t* buf, char* s)
{
	while(*s != '\0') { // until we reach a NULL
		buf->contents[buf->ix_write++] = *s++;
		if( buf->ix_write >= buf->length ){ buf->ix_write = 0; }
		buf->count++;
	}
}

char* str_buffer_dequeue(str_buffer_t* buf, uint16_t size)
{
	char* ret_str = &buf->contents[buf->ix_read];
	buf->count -= size;
	buf->ix_read += size;
	if(buf->ix_read >= buf->length) {buf->ix_read = 0;}
	return ret_str;
}

uint16_t str_buffer_len(str_buffer_t* buf)
{
	uint16_t ret_len = buf->count;
	if( (ret_len + buf->ix_read) > buf->length){
		ret_len = buf->length - buf->ix_read;
	}
	return ret_len;
}

uint8_t str_buffer_empty(str_buffer_t* buf)
{
	return (!buf->count);
}