1 files changed, 151 insertions, 0 deletions
diff --git a/obi.c b/obi.c
new file mode 100644
index 0000000..72cff00
--- /dev/null
+++ b/obi.c
@@ -0,0 +1,151 @@
+/* obi.c
+ * Created: 2023-09-02
+ * Author: Aryadev Chavali
+ * Description: Entrypoint of interpreter
+ */
+
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "./lib.h"
+#include "./parser.h"
+
+#define MIN_MEM_DUMP 64
+
+typedef struct
+{
+  size_t dp;
+  uint8_t memory[MEMORY_DEFAULT];
+
+#ifdef DEBUG
+  size_t dp_max;
+#endif
+} machine_t;
+
+void interpret(machine_t *cpu, node_t *ast, size_t num)
+{
+  for (size_t i = 0; i < num; ++i)
+  {
+    node_t node = ast[i];
+    switch (node.type)
+    {
+    case NEXT:
+      ++cpu->dp;
+      break;
+    case PREV:
+      --cpu->dp;
+      break;
+    case INC:
+      ++cpu->memory[cpu->dp];
+      break;
+    case DEC:
+      --cpu->memory[cpu->dp];
+      break;
+    case OUT:
+      putchar(cpu->memory[cpu->dp]);
+      break;
+    case READ:
+      cpu->memory[cpu->dp] = getchar();
+      break;
+    case LIN:
+      if (cpu->memory[cpu->dp] == 0)
+        i = node.loop_ref;
+      break;
+    case LOUT:
+      if (cpu->memory[cpu->dp] != 0)
+        i = node.loop_ref;
+      break;
+    }
+#ifdef DEBUG
+    if (cpu->dp > cpu->dp_max)
+      cpu->dp_max = cpu->dp + 1;
+#endif
+  }
+
+#ifdef DEBUG
+  if (cpu->dp_max < MIN_MEM_DUMP)
+    cpu->dp_max = MIN_MEM_DUMP;
+#endif
+}
+
+void usage(const char *name, FILE *fp)
+{
+  fprintf(fp,
+          "Usage: %s [FILE]...\n\tInterprets FILE as a brainfuck program"
+          "\n",
+          name);
+}
+
+int main(int argc, char *argv[])
+{
+  if (argc == 1)
+  {
+    usage(argv[0], stderr);
+    return 1;
+  }
+
+  int ret        = 0;
+  char *filepath = argv[1], *file_data = NULL;
+  buffer_t *buffer   = NULL;
+  struct PResult res = {0};
+  machine_t machine  = {0};
+
+  FILE *handle = fopen(filepath, "r");
+#ifdef DEBUG
+  printf("[DEBUG]: Attempting to open file handle to %s\n", filepath);
+#endif
+  if (!handle)
+  {
+    fprintf(stderr, "ERROR: Could not open \"%s\"\n", filepath);
+    ret = 1;
+    goto end;
+  }
+  file_data = fread_all(handle);
+  fclose(handle);
+#ifdef DEBUG
+  printf("[DEBUG]: Read data from file %s\n", filepath);
+#endif
+
+  buffer = buffer_init_str(filepath, file_data, strlen(file_data));
+#ifdef DEBUG
+  puts("[DEBUG]: Initialised buffer");
+#endif
+  res = parse_buffer(buffer);
+  if (res.nodes == NULL)
+  {
+    fputs("Exiting early...\n", stderr);
+    ret = 1;
+    goto end;
+  }
+
+#ifdef DEBUG
+  char *str = ast_to_str(res.nodes, res.size);
+  printf("[DEBUG]: Parsed buffer (%lu nodes parsed)\n\t[DEBUG]: Out=%s\n",
+         res.size, str);
+  free(str);
+#endif
+
+  interpret(&machine, res.nodes, res.size);
+
+#ifdef DEBUG
+  printf("[DEBUG]: Finished interpreting, memory:");
+  for (size_t i = 0; i < machine.dp_max; ++i)
+  {
+    if (i % 8 == 0)
+      printf("\n\t");
+    printf("%d    ", machine.memory[i]);
+  }
+  printf("\n");
+#endif
+end:
+  if (res.nodes)
+    free(res.nodes);
+  if (buffer)
+    free(buffer);
+  if (file_data)
+    free(file_data);
+  return ret;
+}