initHEADmaster

1 files changed, 212 insertions, 0 deletions

diff --git a/brainfuck.c b/brainfuck.c
new file mode 100644
index 0000000..1579231
--- /dev/null
+++ b/brainfuck.c
@@ -0,0 +1,212 @@
+// Copyright (C) 2023 Dzshy <dzshy@outlook.com>. All Rights Reserved.
+// Licensed under Non-Profit Open Software License ("Non-Profit OSL") 3.0.
+
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <fcntl.h>
+#include <sys/mman.h>
+#include <sys/stat.h>
+
+#include "crc32.h"
+#include "htable.h"
+
+#define LOGGER(s, ...)                                                         \
+    do {                                                                       \
+        fprintf(stderr, s "\n", ##__VA_ARGS__);                                \
+    } while (0)
+
+uint8_t *pbuf;
+uint8_t *nbuf;
+long nsz, psz;
+static const int INIT_SZ = 128;
+
+typedef struct {
+    long key;
+    long val;
+} JmpTblEntry;
+
+static bool jmptbl_eq(void *x, void *y)
+{
+    long *a = x, *b = y;
+    return *a == *b;
+}
+
+static uint32_t jmptbl_hash(void *k) { return crc32(0, k, sizeof(long)); }
+
+HTable jmptbl;
+
+struct listnode {
+    struct listnode *next;
+    long val;
+};
+typedef struct {
+    struct listnode *head;
+} Stack;
+
+void stack_push(Stack *s, long val)
+{
+    struct listnode *n = malloc(sizeof(struct listnode));
+    n->next = s->head;
+    n->val = val;
+    s->head = n;
+}
+
+long *stack_top(Stack *s)
+{
+    if (s->head == NULL)
+        return NULL;
+    return &(s->head->val);
+}
+
+void stack_pop(Stack *s)
+{
+    if (s->head == NULL)
+        return;
+    struct listnode *next = s->head->next;
+    free(s->head);
+    s->head = next;
+}
+
+void buildjmptable(char *buf, long len)
+{
+    Stack s = {0};
+    htable_init(&jmptbl, sizeof(JmpTblEntry), -1, jmptbl_hash, jmptbl_eq);
+    for (long i = 0; i < len; i++) {
+        if (buf[i] == '[') {
+            stack_push(&s, i);
+        } else if (buf[i] == ']') {
+            long j = *stack_top(&s);
+            stack_pop(&s);
+            JmpTblEntry e1 = {i, j};
+            JmpTblEntry e2 = {j, i};
+            htable_insert(&jmptbl, &e1);
+            htable_insert(&jmptbl, &e2);
+        }
+    }
+}
+
+static long tbllookup(long pos)
+{
+    JmpTblEntry *iter = htable_find(&jmptbl, &pos);
+    return iter->val;
+}
+
+void ensurespc_impl(uint8_t **buf, long *cursz, long ptr)
+{
+    if (ptr > *cursz) {
+        *buf = realloc(*buf, ptr * 2);
+        memset((*buf) + (*cursz), 0, 2 * ptr - (*cursz));
+        *cursz = ptr * 2;
+    }
+}
+
+void ensurespc(long ptr)
+{
+    if (ptr >= 0) {
+        ensurespc_impl(&pbuf, &psz, ptr);
+    } else {
+        ensurespc_impl(&nbuf, &nsz, -ptr);
+    }
+}
+
+uint8_t getdata(long ptr)
+{
+    ensurespc(ptr);
+    if (ptr >= 0)
+        return pbuf[ptr];
+    else
+        return nbuf[-ptr];
+}
+
+void setdata(long ptr, uint8_t val)
+{
+    ensurespc(ptr);
+    if (ptr >= 0)
+        pbuf[ptr] = val;
+    else
+        nbuf[-ptr] = val;
+}
+
+void interp(char *prog, long prog_sz)
+{
+    long prog_p = 0;
+    long data_p = 0;
+    nbuf = malloc(INIT_SZ);
+    pbuf = malloc(INIT_SZ);
+    nsz = INIT_SZ;
+    psz = INIT_SZ;
+    memset(nbuf, 0, INIT_SZ);
+    memset(pbuf, 0, INIT_SZ);
+
+    while (prog_p < prog_sz) {
+        switch (prog[prog_p]) {
+        case '>':
+            data_p++;
+            break;
+        case '<':
+            data_p--;
+            break;
+        case '+':
+            setdata(data_p, getdata(data_p) + 1);
+            break;
+        case '-':
+            setdata(data_p, getdata(data_p) - 1);
+            break;
+        case '.':
+            putchar(getdata(data_p));
+            break;
+        case ',':
+            setdata(data_p, getchar());
+            break;
+        case '[':
+            if (getdata(data_p) == 0) {
+                prog_p = tbllookup(prog_p);
+            }
+            break;
+        case ']':
+            if (getdata(data_p) != 0) {
+                prog_p = tbllookup(prog_p);
+            }
+            break;
+        default:
+            break;
+        }
+        prog_p++;
+    }
+}
+
+int main(int argc, char **argv)
+{
+    if (argc < 2) {
+        LOGGER("invalid args");
+        return EXIT_FAILURE;
+    }
+    int fd = open(argv[1], O_RDONLY);
+    if (fd < 0) {
+        return EXIT_FAILURE;
+    }
+    struct stat fst;
+    int ret = fstat(fd, &fst);
+    if (ret != 0) {
+        LOGGER("error: failed to get file stat");
+        return EXIT_FAILURE;
+    }
+    long filesz = fst.st_size;
+    char *prog = malloc(filesz);
+    FILE *fp = fdopen(fd, "r");
+    if (fp == NULL) {
+        LOGGER("error opening file");
+        exit(-1);
+    }
+    size_t read = fread(prog, 1, filesz, fp);
+    if (read < filesz) {
+        LOGGER("erro reading");
+        exit(-1);
+    }
+    buildjmptable(prog, filesz);
+    interp(prog, filesz);
+    return EXIT_SUCCESS;
+}