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#include <stdlib.h>
#include <stdio.h>
/* Unstructured switch statements */
/* Duff's device */
void send(char * to, char * from, int count)
{
register int n = (count + 7) / 8;
switch (count % 8) {
case 0: do { *to++ = *from++;
case 7: *to++ = *from++;
case 6: *to++ = *from++;
case 5: *to++ = *from++;
case 4: *to++ = *from++;
case 3: *to++ = *from++;
case 2: *to++ = *from++;
case 1: *to++ = *from++;
} while (--n > 0);
}
}
/* OpenBSD, usr.bin/locale */
void quotestring(char * value, int double_quoted)
{
char c;
while ((c = *value++) != '\0')
switch (c) {
case ' ': case '\t': case '\n': case '\'':
case '(': case ')': case '<': case '>':
case '&': case ';': case '|': case '~':
if (!double_quoted)
case '"': case '\\': case '$': case '`':
putchar('\\');
default:
putchar(c);
break;
}
}
/* Simon Tatham's coroutines */
int nextchar(void)
{
static unsigned char input[] = {
'a', 'b', 0xFF, 3, 'c', 'd', 0xFF, 2, 'e', '\n', 0
};
static unsigned char * next = input;
if (*next == 0)
return EOF;
else
return *next++;
}
#define crBegin static int state=0; switch(state) { case 0:
#define crReturn(x) do { state=__LINE__; return x; \
case __LINE__:; } while (0)
#define crFinish }
int decompressor(void) {
static int c, len;
crBegin;
while (1) {
c = nextchar();
if (c == EOF)
break;
if (c == 0xFF) {
len = nextchar();
c = nextchar();
while (len--)
crReturn(c);
} else
crReturn(c);
}
crReturn(EOF);
crFinish;
}
/* Pigeon's device */
static enum { REVDFWDT, FORWARD, REVERSE } sorting_mode;
#define DAYOF(stamp) ((stamp) / 10000)
#define TIMEOF(stamp) ((stamp) % 10000)
static inline int intcmp(unsigned int x, unsigned int y)
{
if (x < y) return -1;
if (x > y) return 1;
return 0;
}
int lfdcmp(const void *a, const void *b) {
unsigned int ta = *((unsigned int *) a);
unsigned int tb = *((unsigned int *) b);
/* Isn't C a wonderful language? */
switch (sorting_mode) {
case REVDFWDT: if (DAYOF(ta) == DAYOF(tb)) {
case FORWARD : return intcmp(ta, tb);
} else {
case REVERSE : return intcmp(tb, ta);
}
}
return 0;
}
void testpigeon(int mode)
{
unsigned int data[6] = {
10001, 10004, 20022, 20002, 30008, 30007
};
sorting_mode = mode;
qsort(data, 6, sizeof(unsigned int), lfdcmp);
for (int i = 0; i < 6; i++) printf("%5u ", data[i]);
printf("\n");
}
/* Delicate cases: unstructured switch containing
early break
loop w/ break
regular switch
*/
void torture(int a, int b)
{
switch(a) {
L1: printf("L1 "); /*fallthrough*/
L2: printf("L2 "); break;
case 0:
printf("0 "); /*fallthrough*/
case 1:
printf("1 "); break;
case 2:
printf("2 "); goto L1;
case 3:
L3:
printf("3 "); goto L2;
case 4:
printf("4 "); goto L3;
case 5:
while (1) { printf("5"); b--; if (b <= 0) { printf(" "); break; }};
break;
case 6:
switch (b) {
case 1: printf("60"); break;
case 2: printf("61"); break;
default: printf("6X");
}
printf("Y ");
break;
default:
printf("? ");
}
}
int main()
{
char dest[16];
send(dest, "0123456789AB", 13);
printf("%s\n", dest);
quotestring("(ab$cd)", 0); putchar('\n');
quotestring("(ab$cd)", 1); putchar('\n');
int c;
while ((c = decompressor()) != EOF) putchar(c);
testpigeon(FORWARD);
testpigeon(REVERSE);
testpigeon(REVDFWDT);
torture(0, 0); torture(1, 0); torture(2, 0); torture(3, 0); torture(4, 0);
printf("\n");
for (int b = 1; b <= 3; b++) torture(5, b);
printf("\n");
for (int b = 1; b <= 3; b++) torture(6, b);
printf("\n");
return 0;
}
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