/*
* naive implementation of "gets"
* (big difference from fgets == strips newline character)
*/
char* sgets(char *s)
{
char *retval = s;
char ch;
while ((ch = (char)xgetchar()))
{
if (ch == 0x0d) /* user typed enter */
{
printf("\n");
break;
}
else if (ch == 0x08) /* user typed backspace */
{
printf ("\b");
printf (" ");
printf ("\b");
s--;
}
else /* user typed another character */
{
printf("%c", ch);
*s++ = ch;
}
}
*s = '\0';
return retval;
}
/* Read one line, including the newline, into s. Safely avoids buffer
* overruns (but that's kind of pointless because there are several
* other places where I'm not so careful). */
static void getline_(char *s)
{
int c;
char *p;
fflush(stdout);
p = s;
while (p < s + INPUT_BUFFER_SIZE - 1)
if ((*p++ = xgetchar()) == '\n') {
*p = '\0';
return;
}
p[-1] = '\n';
p[0] = '\0';
while ((c = xgetchar()) != '\n')
;
printf("Line too long, truncated to %s\n", s - INPUT_BUFFER_SIZE);
}
char *xgets(char *s) {
int c;
char *buf;
xfflush(NULL);
buf = s;
while ((c = xgetchar()) != EOF && c != '\n') {
*buf++ = c;
}
*buf = '\0';
return (c == EOF && buf == s) ? NULL : s;
}
void
panic(const char *fmt,...)
{
va_list ap;
printf("panic: ");
va_start(ap, fmt);
vprintf(fmt, ap);
va_end(ap);
printf("\n");
printf("--> Press a key on the console to reboot <--\n");
xgetchar();
printf("Rebooting...\n");
exit(1);
}
int
pager_output(const char *cp)
{
int action;
if (cp == NULL)
return(0);
for (;;) {
if (*cp == 0)
return(0);
putchar(*cp); /* always emit character */
if (*(cp++) == '\n') { /* got a newline? */
p_freelines--;
if (p_freelines <= 0) {
printf("%s", pager_prompt1);
action = 0;
while (action == 0) {
switch(xgetchar()) {
case '\r':
case '\n':
p_freelines = 1;
action = 1;
break;
case ' ':
p_freelines = p_maxlines;
action = 1;
break;
case 'q':
case 'Q':
action = 2;
break;
default:
break;
}
}
printf("\r%s\r", pager_blank);
if (action == 2)
return(1);
}
}
}
}
static int process(void)
{
int val1, val2;
if(context.stringmode)
{
if(matrix[context.pos.y][context.pos.x] == '"')
context.stringmode = 0;
else
push(matrix[context.pos.y][context.pos.x]);
return 0;
}
if(matrix[context.pos.y][context.pos.x] == ' ')
return 0;
switch(matrix[context.pos.y][context.pos.x])
{
/* @ (end) ends program */
case '@':
return EOP;
case '>': case '<': case '^': case 'v':
context.direction = car2dir(matrix[context.pos.y][context.pos.x]);
break;
/* _ (horizontal if) <boolean value> PC->left if <value>, else PC->right */
case '_':
context.direction = (pop() ? LEFT : RIGHT);
break;
/* | (vertical if) <boolean value> PC->up if <value>, else PC->down */
case '|':
context.direction = (pop() ? UP : DOWN);
break;
/* : (dup) <value> <value> <value> */
case ':':
push(val1 = pop());
push(val1);
break;
/* ? (random) PC -> right? left? up? down? ??? */
case '?':
context.direction = rand() % DIRMAX;
break;
case '+': case '-': case '*': case '/': case '%':
val1 = pop(), val2 = pop();
push(binaryfuncs[binaryopcar2index(matrix[context.pos.y][context.pos.x])](val2, val1));
break;
case '!':
push(!pop());
break;
/* ` (greater) <value1> <value2> <1 if value1 > value2, 0 otherwise> */
case '`':
push(pop() < pop());
break;
/* \ (swap) <value1> <value2> <value2> <value1> */
case '\\':
val1 = pop(), val2 = pop();
push(val1);
push(val2);
break;
/* $ (pop) <value> pops <value> but does nothing */
case '$':
(void) pop();
break;
/* . (pop) <value> outputs <value> as integer */
case '.':
printf("%d", pop());
break;
/* , (pop) <value> outputs <value> as ASCII */
case ',':
putchar(pop());
break;
/* # (bridge) 'jumps' PC one farther; skips over next command */
case '#':
nextcell();
break;
/* ~ (input character) <character user entered> */
case '~':
push(xgetchar());
break;
case '"':
context.stringmode = !context.stringmode;
break;
/* & (input value) <value user entered> */
case '&':
push(getint());
break;
case 'p':
val1 = pop(), val2 = pop();
matrix[val1][val2] = pop();
break;
case 'g':
val1 = pop(), val2 = pop();
push(matrix[val1][val2]);
break;
default:
if(isdigit(matrix[context.pos.y][context.pos.x]))
push(matrix[context.pos.y][context.pos.x] - '0');
}
return 0;
}
