New installation mechanism, updated to 1.5

mach/minix/libsys/_exec.c

@@ -0,0 +1,167 @@
+#include <lib.h>
+#define execl	_execl
+#define execle	_execle
+#define execv	_execv
+#define execve	_execve
+
+extern char **environ;		/* environment pointer */
+
+#define	PTRSIZE	(sizeof(char *))
+_PROTOTYPE( char *_sbrk, (int _incr)					);
+
+#if _ANSI
+#include	<stdarg.h>
+
+PUBLIC int execl(char *name, ...)
+{
+	int retval;
+	va_list ap;
+
+	va_start(ap, name);
+	retval = execve(name, (char **)ap, environ);
+	va_end(ap);
+	return retval;
+}
+#else
+PUBLIC int execl(name, arg0)
+char *name;
+char *arg0;
+{
+  return(execve(name, &arg0, environ));
+}
+#endif
+
+#if _ANSI
+PUBLIC int execle(char *name, ...)
+{
+	int retval;
+	va_list ap;
+	char *p;
+
+	va_start(ap, name);
+	do {
+	    p = va_arg(ap, char *);
+	} while(p);
+	p = (char *)va_arg(ap, char **);
+	va_end(ap);
+	va_start(ap, name);
+	retval = execve(name, (char **)ap, (char **) p);
+	va_end(ap);
+	return retval;
+}
+#else
+PUBLIC int execle(name, argv)
+char *name, *argv;
+{
+  char **p;
+  p = (char **) &argv;
+  while (*p++)			/* null statement */
+	;
+  return(execve(name, &argv, (char **) *p));
+}
+#endif
+
+PUBLIC int execv(name, argv)
+char *name, *argv[];
+{
+
+  return(execve(name, argv, environ));
+}
+
+PUBLIC int execve(path, argv, envp)
+char *path;			/* pointer to name of file to be executed */
+char *argv[];			/* pointer to argument array */
+char *envp[];			/* pointer to environment */
+{
+  register char **argtop;
+  register char **envtop;
+
+	/* Count the argument pointers and environment pointers. */
+  for (argtop = argv; *argtop != (char *) NULL; ) argtop++;
+  for (envtop = envp; *envtop != (char *) NULL; ) envtop++;
+  return(__execve(path, argv, envp, (int)(argtop - argv), (int)(envtop - envp)));
+}
+
+PUBLIC int __execve(path, argv, envp, nargs, nenvps)
+char *path;			/* pointer to name of file to be executed */
+char *argv[];			/* pointer to argument array */
+char *envp[];			/* pointer to environment */
+int nargs;			/* number of args */
+int nenvps;			/* number of environment strings */
+{
+/* This is split off from execve to be called from execvp, so execvp does not
+ * have to allocate up to ARG_MAX bytes just to prepend "sh" to the arg array.
+ */
+
+  char *hp, **ap, *p;
+  int i, stackbytes, npointers, overflow, temp;
+  char *stack;
+  /* Decide how big a stack is needed. Be paranoid about overflow. */
+#if ARG_MAX > INT_MAX
+#error /* overflow checks and sbrk depend on sizes being ints */
+#endif
+  overflow = FALSE;
+  npointers = 1 + nargs + 1 + nenvps + 1;	/* 1's for argc and NULLs */
+  stackbytes = 0;	/* changed because _len is used now */
+  if (nargs < 0 || nenvps < 0 || nargs+nenvps < 0 || npointers < 0)
+	overflow = TRUE;
+  for (i = PTRSIZE; i != 0; i--) {
+	temp = stackbytes + npointers;
+	if (temp < stackbytes) overflow = TRUE;
+	stackbytes = temp;
+  }
+  for (i = 0, ap = argv; i < nargs; i++) {
+	temp = stackbytes + _len(*ap++);
+	if (temp < stackbytes) overflow = TRUE;
+	stackbytes = temp;
+  }
+  for (i = 0, ap = envp; i < nenvps; i++) {
+	temp = stackbytes + _len(*ap++);
+	if (temp < stackbytes) overflow = TRUE;
+	stackbytes = temp;
+  }
+  temp = stackbytes + PTRSIZE - 1;
+  if (temp < stackbytes) overflow = TRUE;
+  stackbytes = (temp / PTRSIZE) * PTRSIZE;
+
+  /* Check for overflow before committing sbrk. */
+  if (overflow || stackbytes > ARG_MAX) {
+	errno = E2BIG;
+	return(-1);
+  }
+
+  /* Allocate the stack. */
+  stack = _sbrk(stackbytes);
+  if (stack == (char *) -1) {
+	errno = E2BIG;
+	return(-1);
+  }
+
+  /* Prepare the stack vector and argc. */
+  ap = (char **) stack;
+  hp = &stack[npointers * PTRSIZE];
+  *ap++ = (char *) nargs;
+
+  /* Prepare the argument pointers and strings. */
+  for (i = 0; i < nargs; i++) {
+	*ap++ = (char *) (hp - stack);
+	p = *argv++;
+	while ((*hp++ = *p++) != 0)
+		;
+  }
+  *ap++ = (char *) NULL;
+
+  /* Prepare the environment pointers and strings. */
+  for (i = 0; i < nenvps; i++) {
+	*ap++ = (char *) (hp - stack);
+	p = *envp++;
+	while ((*hp++ = *p++) != 0)
+		;
+  }
+  *ap++ = (char *) NULL;
+
+  /* Do the real work. */
+  temp = _callm1(MM, EXEC, _len(path), stackbytes, 0, path, stack, NIL_PTR);
+  _sbrk(-stackbytes);
+  return(temp);
+}