zasm: buffer stdin in emulator

Also, add a port for rewinding stdin.
This commit is contained in:
Virgil Dupras 2019-05-10 19:55:01 -04:00
parent 34ee91a0d7
commit 6a804a9c64

View File

@ -18,24 +18,32 @@
* I/O Ports: * I/O Ports:
* *
* 0 - stdin / stdout * 0 - stdin / stdout
* 1 - When written to, rewind stdin buffer to the beginning.
*/ */
// in sync with zasm_glue.asm // in sync with zasm_glue.asm
#define USER_CODE 0x4800 #define USER_CODE 0x4800
#define STDIO_PORT 0x00 #define STDIO_PORT 0x00
#define STDIN_REWIND 0x01
// Other consts
#define STDIN_BUFSIZE 0x8000
static Z80Context cpu; static Z80Context cpu;
static uint8_t mem[0xffff]; static uint8_t mem[0x10000];
// STDIN buffer, allows us to seek and tell
static uint8_t inpt[STDIN_BUFSIZE];
static int inpt_size;
static int inpt_ptr;
static uint8_t io_read(int unused, uint16_t addr) static uint8_t io_read(int unused, uint16_t addr)
{ {
addr &= 0xff; addr &= 0xff;
if (addr == STDIO_PORT) { if (addr == STDIO_PORT) {
int c = getchar(); if (inpt_ptr < inpt_size) {
if (c == EOF) { return inpt[inpt_ptr++];
} else {
return 0; return 0;
} }
return c;
} else { } else {
fprintf(stderr, "Out of bounds I/O read: %d\n", addr); fprintf(stderr, "Out of bounds I/O read: %d\n", addr);
return 0; return 0;
@ -47,6 +55,8 @@ static void io_write(int unused, uint16_t addr, uint8_t val)
addr &= 0xff; addr &= 0xff;
if (addr == STDIO_PORT) { if (addr == STDIO_PORT) {
putchar(val); putchar(val);
} else if (addr == STDIN_REWIND) {
inpt_ptr = 0;
} else { } else {
fprintf(stderr, "Out of bounds I/O write: %d / %d\n", addr, val); fprintf(stderr, "Out of bounds I/O write: %d / %d\n", addr, val);
} }
@ -71,6 +81,20 @@ int main()
for (int i=0; i<sizeof(USERSPACE); i++) { for (int i=0; i<sizeof(USERSPACE); i++) {
mem[i+USER_CODE] = USERSPACE[i]; mem[i+USER_CODE] = USERSPACE[i];
} }
// read stdin in buffer
inpt_size = 0;
inpt_ptr = 0;
int c = getchar();
while (c != EOF) {
inpt[inpt_ptr] = c & 0xff;
inpt_ptr++;
if (inpt_ptr == STDIN_BUFSIZE) {
break;
}
c = getchar();
}
inpt_size = inpt_ptr;
inpt_ptr = 0;
Z80RESET(&cpu); Z80RESET(&cpu);
cpu.ioRead = io_read; cpu.ioRead = io_read;
cpu.ioWrite = io_write; cpu.ioWrite = io_write;