103 lines
		
	
	
	
		
			2.3 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			103 lines
		
	
	
	
		
			2.3 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
#include "lib.h"
 | 
						|
 | 
						|
extern char **environ;			/* environment pointer */
 | 
						|
 | 
						|
#define	PTRSIZE	sizeof(char *)
 | 
						|
 | 
						|
PUBLIC int execl(name, arg0)
 | 
						|
char *name;
 | 
						|
char *arg0;
 | 
						|
{
 | 
						|
  return execve(name, &arg0, environ);
 | 
						|
}
 | 
						|
 | 
						|
PUBLIC int execle(name, argv)
 | 
						|
char *name, *argv;
 | 
						|
{
 | 
						|
  char **p;
 | 
						|
  p = (char **) &argv;
 | 
						|
  while (*p++) /* null statement */ ;
 | 
						|
  return execve(name, &argv, *p);
 | 
						|
}
 | 
						|
 | 
						|
PUBLIC int execv(name, argv)
 | 
						|
char *name, *argv[];
 | 
						|
{
 | 
						|
  return execve(name, argv, environ);
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
PUBLIC int execve(name, argv, envp)
 | 
						|
char *name;			/* pointer to name of file to be executed */
 | 
						|
char *argv[];			/* pointer to argument array */
 | 
						|
char *envp[];			/* pointer to environment */
 | 
						|
{
 | 
						|
  char stack[MAX_ISTACK_BYTES];
 | 
						|
  char **argorg, **envorg, *hp, **ap, *p;
 | 
						|
  int i, nargs, nenvps, stackbytes, offset;
 | 
						|
  extern errno;
 | 
						|
 | 
						|
  /* Count the argument pointers and environment pointers. */
 | 
						|
  nargs = 0;
 | 
						|
  nenvps = 0;
 | 
						|
  argorg = argv;
 | 
						|
  envorg = envp;
 | 
						|
  while (*argorg++ != NIL_PTR) nargs++;
 | 
						|
  while (*envorg++ != NIL_PTR) nenvps++;
 | 
						|
 | 
						|
  /* Prepare to set up the initial stack. */
 | 
						|
  hp = &stack[(nargs + nenvps + 3) * PTRSIZE];
 | 
						|
  if (hp + nargs + nenvps >= &stack[MAX_ISTACK_BYTES]) {
 | 
						|
	errno = E2BIG;
 | 
						|
	return(-1);
 | 
						|
  }
 | 
						|
  ap = (char **) stack;
 | 
						|
  *ap++ = (char *) nargs;
 | 
						|
 | 
						|
  /* Prepare the argument pointers and strings. */
 | 
						|
  for (i = 0; i < nargs; i++) {
 | 
						|
	offset = hp - stack;
 | 
						|
	*ap++ = (char *) offset;
 | 
						|
	p = *argv++;
 | 
						|
	while (*p) {
 | 
						|
		*hp++ = *p++;
 | 
						|
		if (hp >= &stack[MAX_ISTACK_BYTES]) {
 | 
						|
			errno = E2BIG;
 | 
						|
			return(-1);
 | 
						|
		}
 | 
						|
	}
 | 
						|
	*hp++ = (char) 0;
 | 
						|
  }
 | 
						|
  *ap++ = NIL_PTR;
 | 
						|
 | 
						|
  /* Prepare the environment pointers and strings. */
 | 
						|
  for (i = 0; i < nenvps; i++) {
 | 
						|
	offset = hp - stack;
 | 
						|
	*ap++ = (char *) offset;
 | 
						|
	p = *envp++;
 | 
						|
	while (*p) {
 | 
						|
		*hp++ = *p++;
 | 
						|
		if (hp >= &stack[MAX_ISTACK_BYTES]) {
 | 
						|
			errno = E2BIG;
 | 
						|
			return(-1);
 | 
						|
		}
 | 
						|
	}
 | 
						|
	*hp++ = (char) 0;
 | 
						|
  }
 | 
						|
  *ap++ = NIL_PTR;
 | 
						|
  stackbytes = ( ( (int)(hp - stack) + PTRSIZE - 1)/PTRSIZE) * PTRSIZE;
 | 
						|
  return callm1(MM_PROC_NR, EXEC, len(name), stackbytes, 0,name, stack,NIL_PTR);
 | 
						|
}
 | 
						|
 | 
						|
 | 
						|
PUBLIC execn(name)
 | 
						|
char *name;			/* pointer to file to be exec'd */
 | 
						|
{
 | 
						|
/* Special version used when there are no args and no environment.  This call
 | 
						|
 * is principally used by INIT, to avoid having to allocate MAX_ISTACK_BYTES.
 | 
						|
 */
 | 
						|
 | 
						|
  static char stack[3 * PTRSIZE];
 | 
						|
 | 
						|
  return callm1(MM_PROC_NR, EXEC, len(name), sizeof(stack), 0, name, stack, NIL_PTR);
 | 
						|
}
 |