newlib-cygwin/newlib/libc/sys/linux/machine/i386/crt0.c

46 lines
1.3 KiB
C

/* libc/sys/linux/crt0.c - Run-time initialization */
/* FIXME: This should be rewritten in assembler and
placed in a subdirectory specific to a platform.
There should also be calls to run constructors. */
/* Written 2000 by Werner Almesberger */
#include <stdlib.h>
#include <time.h>
#include <string.h>
extern char **environ;
extern int main(int argc,char **argv,char **envp);
extern char _end;
extern char __bss_start;
void _start(int args)
{
/*
* The argument block begins above the current stack frame, because we
* have no return address. The calculation assumes that sizeof(int) ==
* sizeof(void *). This is okay for i386 user space, but may be invalid in
* other cases.
*/
int *params = &args-1;
int argc = *params;
char **argv = (char **) (params+1);
environ = argv+argc+1;
/* Note: do not clear the .bss section. When running with shared
* libraries, certain data items such __mb_cur_max or environ
* may get placed in the .bss, even though they are initialized
* to non-zero values. Clearing the .bss will end up zeroing
* out their initial values. The .bss is already initialized
* by this time by Linux. */
tzset(); /* initialize timezone info */
exit(main(argc,argv,environ));
}