ash: fix "shift BIGNUM" and "read with no variable name" bugs.

 omg. hush testsuite helps to find bugs in ash! what next?

function                                             old     new   delta
static.arg_REPLY                                       -       8      +8
readcmd                                             1023    1021      -2
shiftcmd                                             129     125      -4
------------------------------------------------------------------------------
(add/remove: 1/0 grow/shrink: 0/2 up/down: 8/-6)                Total: 2 bytes

1 files changed, 4 insertions, 2 deletions

diff --git a/shell/ash.c b/shell/ash.c
index b490b69f1..f8e4e7d45 100644
--- a/shell/ash.c
+++ b/shell/ash.c
@@ -9549,7 +9549,7 @@ shiftcmd(int argc ATTRIBUTE_UNUSED, char **argv)
         if (argv[1])
                 n = number(argv[1]);
         if (n > shellparam.nparam)
-                ash_msg_and_raise_error("can't shift that many");
+                n = shellparam.nparam;
         INT_OFF;
         shellparam.nparam -= n;
         for (ap1 = shellparam.p; --n >= 0; ap1++) {
@@ -11994,6 +11994,8 @@ typedef enum __rlimit_resource rlim_t;
 static int
 readcmd(int argc ATTRIBUTE_UNUSED, char **argv ATTRIBUTE_UNUSED)
 {
+        static const char *const arg_REPLY[] = { "REPLY", NULL };
+
         char **ap;
         int backslash;
         char c;
@@ -12086,7 +12088,7 @@ readcmd(int argc ATTRIBUTE_UNUSED, char **argv ATTRIBUTE_UNUSED)
         }
         ap = argptr;
         if (*ap == NULL)
-                ash_msg_and_raise_error("arg count");
+                ap = (char**)arg_REPLY;
         ifs = bltinlookup("IFS");
         if (ifs == NULL)
                 ifs = defifs;