// Written by retoor@molodetz.nl
// A ring buffer implementation in C that provides functionalities such as
// creating a new buffer, freeing, resetting, writing data, pushing data,
// popping data, matching options and more. It efficiently manages dynamic
// memory to handle data of varying sizes and applies basic buffer manipulation techniques.
// This code includes the utility "rmalloc.h". It is assumed that this file
// contains custom memory management functions which are not specified here.
// MIT License
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.
#ifndef RBUFFER_H
#define RBUFFER_H
#include "rmalloc.h"
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <stdbool.h>
#include <assert.h>
typedef struct rbuffer_t {
unsigned char *data;
unsigned char *_data;
size_t size;
size_t pos;
bool eof;
} rbuffer_t;
rbuffer_t *rbuffer_new(unsigned char *data, size_t size);
void rbuffer_free(rbuffer_t *rfb);
void rbuffer_reset(rbuffer_t *rfb);
void rbuffer_write(rbuffer_t *rfb, const unsigned char *data, size_t size);
size_t rbuffer_push(rbuffer_t *rfb, unsigned char data);
unsigned char rbuffer_pop(rbuffer_t *rfb);
unsigned char *rbuffer_expect(rbuffer_t *rfb, char *options, char *ignore);
void rbuffer_set(rbuffer_t *rfb, const unsigned char *data, size_t size);
void rbuffer_set(rbuffer_t *rfb, const unsigned char *data, size_t size) {
if (rfb->_data) {
free(rfb->_data);
rfb->_data = NULL;
rfb->data = NULL;
rfb->eof = true;
}
if (size) {
rfb->_data = (unsigned char *)malloc(size);
memcpy(rfb->_data, data, size);
rfb->data = rfb->_data;
rfb->eof = false;
}
rfb->size = size;
rfb->pos = 0;
}
rbuffer_t *rbuffer_new(unsigned char *data, size_t size) {
rbuffer_t *rfb = (rbuffer_t *)malloc(sizeof(rbuffer_t));
if (size) {
rfb->_data = (unsigned char *)malloc(size);
memcpy(rfb->_data, data, size);
rfb->eof = false;
} else {
rfb->_data = NULL;
rfb->eof = true;
}
rfb->size = size;
rfb->pos = 0;
rfb->data = rfb->_data;
return rfb;
}
void rbuffer_free(rbuffer_t *rfb) {
if (rfb->_data) {
free(rfb->_data);
}
free(rfb);
}
size_t rbuffer_push(rbuffer_t *rfb, unsigned char data) {
if (rfb->pos < rfb->size) {
rfb->_data[rfb->pos++] = data;
return 1;
}
rfb->_data = realloc(rfb->_data, rfb->size ? rfb->size + 1 : rfb->size + 2);
rfb->_data[rfb->pos++] = data;
rfb->size++;
return rfb->pos;
}
void rbuffer_write(rbuffer_t *rfb, const unsigned char *data, size_t size) {
for (size_t i = 0; i < size; i++) {
rbuffer_push(rfb, data[i]);
}
}
unsigned char rbuffer_peek(rbuffer_t *rfb) {
if (rfb->pos != rfb->size) {
return rfb->_data[rfb->pos];
}
rfb->eof = true;
return EOF;
}
unsigned char rbuffer_pop(rbuffer_t *rfb) {
if (rfb->pos < rfb->size) {
unsigned char result = rfb->_data[rfb->pos];
rfb->pos++;
rfb->data++;
if (rfb->pos == rfb->size) {
rfb->eof = true;
}
return result;
}
rfb->eof = true;
return EOF;
}
void rbuffer_reset(rbuffer_t *rfb) {
rfb->data = rfb->_data;
rfb->pos = 0;
}
unsigned char ustrncmp(const unsigned char *s1, const unsigned char *s2, size_t n) {
return strncmp((const char *)s1, (const char *)s2, n);
}
size_t ustrlen(const unsigned char *s) { return strlen((const char *)s); }
unsigned char *rbuffer_to_string(rbuffer_t *rfb) {
unsigned char *result = rfb->_data;
rfb->_data = NULL;
rfb->data = NULL;
rbuffer_free(rfb);
return result;
}
unsigned char *rbuffer_match_option(rbuffer_t *rfb, char *options) {
char *option = NULL;
char options_cpy[1024] = {0};
strcpy(options_cpy, options);
char *memory = options_cpy;
while ((option = strtok_r(option == NULL ? memory : NULL, "|", &memory)) != NULL) {
size_t option_length = strlen(option);
if (option_length > rfb->size - rfb->pos) {
continue;
}
if (!strcmp(option, "\\d") && *rfb->data >= '0' && *rfb->data <= '9') {
return rfb->data;
}
if (rfb->size - rfb->pos >= 5 && !strcmp(option, "\\b") &&
((!ustrncmp(rfb->data, (unsigned char *)"true", 4) || !ustrncmp(rfb->data, (unsigned char *)"false", 5)))) {
return rfb->data;
}
if (!ustrncmp(rfb->data, (unsigned char *)option, option_length)) {
return rfb->data;
}
}
return NULL;
}
unsigned char *rbuffer_expect(rbuffer_t *rfb, char *options, char *ignore) {
while (rfb->pos < rfb->size) {
if (rbuffer_match_option(rfb, options) != NULL) {
return rfb->data;
}
if (rbuffer_match_option(rfb, ignore)) {
printf("SKIP:%s\n", rfb->data);
rbuffer_pop(rfb);
continue;
}
break;
}
return NULL;
}
unsigned char *rbuffer_consume(rbuffer_t *rfb, char *options, char *ignore) {
unsigned char *result = NULL;
if ((result = rbuffer_expect(rfb, options, ignore)) != NULL) {
rbuffer_pop(rfb);
}
return result;
}
#endif
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