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/*
* This test program will register the maximum number of exit functions
* with atexit(). When this program exits, each exit function should get
* called in the reverse order in which it was registered. (If the system
* supports more than 25 exit functions, the function names will loop, but
* the effect will be the same. Feel free to add more functions if desired)
*/
#include <stdio.h>
#include <stdlib.h>
typedef void (*vfuncp) (void);
/* All functions call exit(), in order to test that exit functions can call
* exit() without screwing everything up. :)
*/
#define make_exitfunc(num) \
__attribute__ ((__noreturn__)) static \
void exitfunc##num(void) \
{ \
printf("Executing exitfunc"#num".\n"); \
exit(0); \
}
make_exitfunc(0)
make_exitfunc(1)
make_exitfunc(2)
make_exitfunc(3)
make_exitfunc(4)
make_exitfunc(5)
make_exitfunc(6)
make_exitfunc(7)
make_exitfunc(8)
make_exitfunc(9)
make_exitfunc(10)
make_exitfunc(11)
make_exitfunc(12)
make_exitfunc(13)
make_exitfunc(14)
make_exitfunc(15)
make_exitfunc(16)
make_exitfunc(17)
make_exitfunc(18)
make_exitfunc(19)
make_exitfunc(20)
make_exitfunc(21)
make_exitfunc(22)
make_exitfunc(23)
make_exitfunc(24)
static vfuncp func_table[] =
{
exitfunc0, exitfunc1, exitfunc2, exitfunc3, exitfunc4,
exitfunc5, exitfunc6, exitfunc7, exitfunc8, exitfunc9,
exitfunc10, exitfunc11, exitfunc12, exitfunc13, exitfunc14,
exitfunc15, exitfunc16, exitfunc17, exitfunc18, exitfunc19,
exitfunc20, exitfunc21, exitfunc22, exitfunc23, exitfunc24
};
/* glibc dynamically adds exit functions, so it will keep adding until
* it runs out of memory! So this will limit the number of exit functions
* we add in the loop below. uClibc has a set limit (currently 20), so the
* loop will go until it can't add any more (so it should not hit this limit).
*/
#define ATEXIT_LIMIT 20
int
main ( void )
{
int i = 0;
int count = 0;
int numfuncs = sizeof(func_table)/sizeof(vfuncp);
/* loop until no more can be added */
while(count < ATEXIT_LIMIT && atexit(func_table[i]) >= 0) {
printf("Registered exitfunc%d with atexit()\n", i);
count++;
i = (i+1) % numfuncs;
}
printf("%d functions registered with atexit.\n", count);
return 0;
}
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