WIP on superzazu-based emulator

HOST/em8080.c

@@ -0,0 +1,147 @@
+// This file uses the 8080 emulator to run the test suite (roms in cpu_tests
+// directory). It uses a simple array as memory.
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#include "8080/i8080.h"
+
+// memory callbacks
+#define MEMORY_SIZE 0x10000
+static uint8_t* memory = NULL;
+static bool test_finished = 0;
+
+static uint8_t rb(void* userdata, const uint16_t addr) {
+    return memory[addr];
+}
+
+static void wb(void* userdata, const uint16_t addr, const uint8_t val) {
+    memory[addr] = val;
+}
+
+uint16_t dma_addr;
+uint8_t cur_disk = 'Z'-'A';
+char filename[16];
+
+void filename_from_fcb(void* userdata, uint16_t addr) {
+  i8080* const c = (i8080*) userdata;
+  memset(&filename, 0, sizeof(filename));
+  char* ptr = filename;
+  while(rb(c, addr) != '.' && rb(c, addr) > ' ') {
+    *ptr++ = rb(c, addr++);
+  }
+  if (rb(c, addr) == '.') {
+    addr++;
+    while(rb(c, addr) > ' ') {
+      *ptr++ = rb(c, addr++);
+    }
+  }
+}
+
+void filename_to_fcb(void* userdata, uint16_t addr) {
+
+}
+
+static uint8_t port_in(void* userdata, uint8_t port) {
+  i8080* const c = (i8080*) userdata;
+  uint16_t de = (c->d << 8) | c->e;
+
+  switch(c->c) {
+  case 2:
+    printf("%c", c->e);
+    break;
+  case 9:
+    do {
+      printf("%c", rb(c, de++));
+    } while(rb(c, de) != '$');
+    break;
+  case 15:
+    filename_from_fcb(userdata, de);
+    printf("filename: %s\n", filename);
+    exit(1);
+    break;
+  case 25:
+    c->a = cur_disk;
+    break;
+  case 26:
+    dma_addr = (c->d << 8) | c->e;
+    break;
+  default:
+    i8080_debug_output(c);
+    fprintf(stderr, "fatal: unknown syscall C=%02Xh (%d)\n", c->c, c->c);
+    exit(255);
+  }
+
+  return c->a;
+}
+
+static int load_file(const char* filename, uint16_t addr) {
+    FILE* f = fopen(filename, "rb");
+    if (f == NULL) {
+        fprintf(stderr, "error: can't open file '%s'.\n", filename);
+        return 1;
+    }
+
+    // file size check:
+    fseek(f, 0, SEEK_END);
+    size_t file_size = ftell(f);
+    rewind(f);
+
+    if (file_size + addr >= MEMORY_SIZE) {
+        fprintf(stderr, "error: file %s can't fit in memory.\n", filename);
+        return 1;
+    }
+
+    // copying the bytes in memory:
+    size_t result = fread(&memory[addr], sizeof(uint8_t), file_size, f);
+    if (result != file_size) {
+        fprintf(stderr, "error: while reading file '%s'\n", filename);
+        return 1;
+    }
+
+    fclose(f);
+    return 0;
+}
+
+int main(int argc, char** argv) {
+    memory = malloc(MEMORY_SIZE);
+    if (memory == NULL) {
+        return 255;
+    }
+
+    argc--;
+    if (!argc) {
+      fprintf(stderr, "No filename given\n");
+    }
+
+    i8080 cpu;
+    i8080_init(&cpu);
+    cpu.userdata = &cpu;
+    cpu.read_byte = rb;
+    cpu.write_byte = wb;
+    cpu.port_in = port_in;
+    memset(memory, 0, MEMORY_SIZE);
+
+    if (load_file(argv[0], 0x100) != 0) {
+        return 255;
+    }
+
+    cpu.pc = 0x100;
+    // inject "hlt" at 0x0000
+    memory[0x0000] = 0x76;
+
+    // inject "in a,0" at 0x0005 (cpm syscall)
+    memory[0x0005] = 0xDB;
+    memory[0x0006] = 0x00;
+    memory[0x0007] = 0xC9;
+
+    while (!cpu.halted) {
+//        i8080_debug_output(&cpu);
+        i8080_step(&cpu);
+    }
+
+    free(memory);
+
+    return cpu.a;
+}