Implemented a brainfuck object which holds all variables

This commit is contained in:
id101010
2016-11-14 03:00:38 +01:00
parent fc24af9195
commit 58fd208ef9
2 changed files with 87 additions and 61 deletions

146
bfckr.c
View File

@@ -12,21 +12,46 @@
#include<errno.h>
#include<assert.h>
#include<ctype.h>
#include<stdbool.h>
// Amount of memory on the band tape
// Defines
#define MEMORY_SIZE 10000
#define MAX_INPUT_SIZE 10000
#define clear() printf("\033[H\033[J")
// Memory initialized with zeros and its pointer
char memory[MEMORY_SIZE] = {0};
char *p = memory;
int memcnt = 0;
// Struct which holds the brainfuck code, the bandtape and some helpervariables
typedef struct bf_code_s {
char memory[MEMORY_SIZE]; // Memory initialized
size_t mp; // Memory pointer
char code[MAX_INPUT_SIZE]; // Input buffer for the bf code
size_t ip; // Instruction pointer
bool debug; // debug flag
} bf_code_t;
// Prototypes
void bfuck_parser(char *input);
void bfuck_parser(bf_code_t *bf);
void bfuck_debugger(bf_code_t *bf);
void print_sourceviewer(bf_code_t *bf);
void print_memoryviewer(bf_code_t *bf);
void init_bf_object(bf_code_t *bf);
// Error handler
/* initialize bf object */
void init_bf_object(bf_code_t *bf)
{
bf->mp = 0; // set data pointer to zero
bf->ip = 0; // set instruction pointer to zero
bf->debug = false; // reset the debug flag
for(size_t i = 0; i < MEMORY_SIZE; i++) {
bf->memory[i] = 0;
}
for(size_t i = 0; i < MAX_INPUT_SIZE; i++) {
bf->code[i] = 0;
}
}
/* Error handler */
void die(const char *message)
{
if(errno) {
@@ -38,40 +63,40 @@ void die(const char *message)
exit(EXIT_FAILURE);
}
// Prints the bf source at the current location
void print_sourceviewer()
/* Prints the bf source at the current location */
void print_sourceviewer(bf_code_t *bf)
{
printf("Source viewer:"
"-----------------------------------------------------------"
"_____________________________>+++++++++++++++[<+>>>>>>>>+++"
" ^ "
" ip=0 "
"-----------------------------------------------------------"); // just to get the idea ...
printf("\nSource viewer: \n"
"-----------------------------------------------------------\n"
"_____________________________>+++++++++++++++[<+>>>>>>>>+++\n"
" ^ \n"
" ip=0 \n"
"-----------------------------------------------------------\n"); // just to get the idea ...
}
// Prints memory information at the current memory location
void print_memoryviewer()
/* Prints memory information at the current memory location */
void print_memoryviewer(bf_code_t *bf)
{
int pointerlocation = (p - memory)*sizeof(*memory); // find the arrayindex at which the pointer is pointing
// int pointerlocation = (p - memory)*sizeof(*memory); // find the arrayindex at which the pointer is pointing
printf("Memory viewer: "
"-----------------------------------------------------------"
"000 000 000 000 000 000 001 001 000 000 000 000 000 000 000"
" ^ "
" mp=1 "
"249 250 251 252 253 254 000 001 002 003 004 005 006 007 008"
"-----------------------------------------------------------"); // just to get the idea ...
printf("\nMemory viewer: \n"
"-----------------------------------------------------------\n"
"000 000 000 000 000 000 001 001 000 000 000 000 000 000 000\n"
" ^ \n"
" mp=1 \n"
"249 250 251 252 253 254 000 001 002 003 004 005 006 007 008\n"
"-----------------------------------------------------------\n"); // just to get the idea ...
}
// Pauses the program flow and prints information
void bfuck_debugger(char *bf_source_input, int instructionpointer)
/* Pauses the program flow and prints information */
void bfuck_debugger(bf_code_t *bf) //char *bf_source_input, int instructionpointer)
{
clear(); // clear terminal
printf("[s]: single step [c]: continue");
printf("[s]: single step [c]: continue\n");
print_sourceviewer();
print_memoryviewer();
print_sourceviewer(bf);
print_memoryviewer(bf);
switch(getchar()) {
case 's':
@@ -79,64 +104,61 @@ void bfuck_debugger(char *bf_source_input, int instructionpointer)
break;
case 'c':
// continue
bf->debug = false;
break;
}
}
// Parses and executes a brainfuck expression
void bfuck_execute(char *input)
/* Parses and executes a brainfuck expression */
void bfuck_execute(bf_code_t *bf)
{
int loop = 0;
for(size_t i = 0; input[i] != 0; i++) { // where i is the instruction pointer
switch(input[i]) {
for(size_t i = bf->ip; bf->code[i] != 0; bf->ip=i++) { // where i is the instruction pointer
switch(bf->code[i]) {
case '>':
if(memcnt >= MEMORY_SIZE) { // prevent overrun
p = &memory[0];
memcnt = 0;
if(bf->mp >= MEMORY_SIZE) { // prevent overrun
bf->mp = 0;
} else {
++p; // increment data pointer
++memcnt;
++(bf->mp); // increment memory pointer
}
break;
case '<':
if(memcnt < 0) { // prevent underun
p = &memory[MEMORY_SIZE - 1];
memcnt = MEMORY_SIZE - 1;
if(bf->mp < 0) { // prevent underun
bf->mp = MEMORY_SIZE-1;
} else {
--p; // decrement data pointer
--memcnt;
--(bf->mp); // decrement memory pointer
}
break;
case '+':
++(*p); // increment byte at data pointer
++(bf->memory[bf->mp]); // increment byte at memory pointer
break;
case '-':
--(*p); // decrement byte at data pointer
--(bf->memory[bf->mp]); // decrement byte at memory pointer
break;
case '.':
putchar(*p); // output the byte at data pointer
putchar(bf->memory[bf->mp]); // output the byte at memory pointer
break;
case ',':
*p = getchar(); // accept one byte of input and store it at data pointer
bf->memory[bf->mp] = getchar(); // accept one byte of input and store it at memory pointer
break;
case '[':
if(*p == 0) { // if the byte at the data pointer is zero
if(bf->memory[bf->mp] == 0) { // if the byte at the memory pointer is zero
// jump forward to the command after the next ]
loop = 1;
while(loop > 0) { // count nested loops and make sure to get the matching ]
i++;
if(input[i] == '[') {
bf->ip = i++;
if(bf->code[i] == '[') {
loop++;
}
if(input[i] == ']') {
if(bf->code[i] == ']') {
loop--;
}
}
@@ -146,15 +168,15 @@ void bfuck_execute(char *input)
break;
case ']':
if(*p != 0) { // if the byte at the data pointer is nonzero
if(bf->memory[bf->mp] != 0) { // if the byte at the memory pointer is nonzero
// jump back to the command after the matching [
loop = 1;
while(loop > 0) { // count nested loops and make sure to get the matching [
i--;
if(input[i] == '[') {
bf->ip = i--;
if(bf->code[i] == '[') {
loop--;
}
if(input[i] == ']') {
if(bf->code[i] == ']') {
loop++;
}
}
@@ -166,6 +188,7 @@ void bfuck_execute(char *input)
case '#':
// Breakpoint reached, start debugger ...
bf->debug = true;
break;
default:
@@ -180,13 +203,16 @@ int main(int argc, char* argv[])
FILE *fp;
int i = 0;
int c;
char input[MAX_INPUT_SIZE];
bf_code_t bf;
// check arguments
if(argc < 2) {
die("Need more arguments.");
}
// initialize bf object
init_bf_object(&bf);
// try to open file
if((fp = fopen(argv[1], "rt")) == NULL) {
die("Couldn't open file.");
@@ -194,14 +220,14 @@ int main(int argc, char* argv[])
// read the file and store it in the input buffer
while((c = getc(fp)) != EOF) {
input[i++] = c;
bf.code[i++] = c;
}
// close file after reading
fclose(fp);
// try to interpret it
bfuck_execute(input);
bfuck_execute(&bf);
// exit
exit(EXIT_SUCCESS);