/* expr.c -- arithmetic expression evaluation. */
-/* Copyright (C) 1990, 1991 Free Software Foundation, Inc.
+/* Copyright (C) 1990-2021 Free Software Foundation, Inc.
This file is part of GNU Bash, the Bourne Again SHell.
- Bash is free software; you can redistribute it and/or modify it
- under the terms of the GNU General Public License as published by
- the Free Software Foundation; either version 1, or (at your option)
- any later version.
+ Bash is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
- Bash is distributed in the hope that it will be useful, but WITHOUT
- ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public
- License for more details.
+ Bash is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
You should have received a copy of the GNU General Public License
- along with Bash; see the file COPYING. If not, write to the Free
- Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
+ along with Bash. If not, see <http://www.gnu.org/licenses/>.
+*/
/*
- All arithmetic is done as long integers with no checking for overflow
+ All arithmetic is done as intmax_t integers with no checking for overflow
(though division by 0 is caught and flagged as an error).
The following operators are handled, grouped into a set of levels in
order of decreasing precedence.
+ "id++", "id--" [post-increment and post-decrement]
"-", "+" [(unary operators)]
+ "++id", "--id" [pre-increment and pre-decrement]
"!", "~"
"**" [(exponentiation)]
"*", "/", "%"
"||"
"expr ? expr : expr"
"=", "*=", "/=", "%=", "+=", "-=", "<<=", ">>=", "&=", "^=", "|="
+ , [comma]
(Note that most of these operators have special meaning to bash, and an
entire expression should be quoted, e.g. "a=$a+1" or "a=a+1" to ensure
Implementation is a recursive-descent parser.
Chet Ramey
- chet@ins.CWRU.Edu
+ chet@po.cwru.edu
*/
#include "config.h"
# include <unistd.h>
#endif
+#include "chartypes.h"
+#include "bashintl.h"
+
#include "shell.h"
+#include "arrayfunc.h"
+#include "execute_cmd.h"
+#include "flags.h"
+#include "subst.h"
+#include "typemax.h" /* INTMAX_MAX, INTMAX_MIN */
/* Because of the $((...)) construct, expressions may include newlines.
Here is a macro which accepts newlines, tabs and spaces as whitespace. */
#define cr_whitespace(c) (whitespace(c) || ((c) == '\n'))
-/* Size be which the expression stack grows when neccessary. */
+/* Size be which the expression stack grows when necessary. */
#define EXPR_STACK_GROW_SIZE 10
/* Maximum amount of recursion allowed. This prevents a non-integer
#define OP_ASSIGN 11 /* op= expassign as in Posix.2 */
#define COND 12 /* exp1 ? exp2 : exp3 */
#define POWER 13 /* exp1**exp2 */
+#define PREINC 14 /* ++var */
+#define PREDEC 15 /* --var */
+#define POSTINC 16 /* var++ */
+#define POSTDEC 17 /* var-- */
#define EQ '='
#define GT '>'
#define LT '<'
#define BNOT '~' /* Bitwise NOT; Two's complement. */
#define QUES '?'
#define COL ':'
+#define COMMA ','
+
+/* This should be the function corresponding to the operator with the
+ lowest precedence. */
+#define EXP_LOWEST expcomma
+
+#ifndef MAX_INT_LEN
+# define MAX_INT_LEN 32
+#endif
+
+struct lvalue
+{
+ char *tokstr; /* possibly-rewritten lvalue if not NULL */
+ intmax_t tokval; /* expression evaluated value */
+ SHELL_VAR *tokvar; /* variable described by array or var reference */
+ intmax_t ind; /* array index if not -1 */
+};
+
+/* A structure defining a single expression context. */
+typedef struct {
+ int curtok, lasttok;
+ char *expression, *tp, *lasttp;
+ intmax_t tokval;
+ char *tokstr;
+ int noeval;
+ struct lvalue lval;
+} EXPR_CONTEXT;
static char *expression; /* The current expression */
static char *tp; /* token lexical position */
static int lasttok; /* the previous token */
static int assigntok; /* the OP in OP= */
static char *tokstr; /* current token string */
-static int tokval; /* current token value */
+static intmax_t tokval; /* current token value */
static int noeval; /* set to 1 if no assignment to be done */
static procenv_t evalbuf;
-static void readtok (); /* lexical analyzer */
-static long subexpr (), expassign (), exp0 (), exp1 (), exp2 (), exp3 (),
- exp4 (), exp5 (), expshift (), expland (), explor (),
- expband (), expbor (), expbxor (), expcond (), exppower ();
-static long strlong ();
-static void evalerror ();
+/* set to 1 if the expression has already been run through word expansion */
+static int already_expanded;
-/* A structure defining a single expression context. */
-typedef struct {
- int curtok, lasttok;
- char *expression, *tp;
- int tokval;
- char *tokstr;
-} EXPR_CONTEXT;
+static struct lvalue curlval = {0, 0, 0, -1};
+static struct lvalue lastlval = {0, 0, 0, -1};
+
+static int _is_arithop PARAMS((int));
+static void readtok PARAMS((void)); /* lexical analyzer */
+
+static void init_lvalue PARAMS((struct lvalue *));
+static struct lvalue *alloc_lvalue PARAMS((void));
+static void free_lvalue PARAMS((struct lvalue *));
+
+static intmax_t expr_streval PARAMS((char *, int, struct lvalue *));
+static intmax_t strlong PARAMS((char *));
+static void evalerror PARAMS((const char *));
+
+static void pushexp PARAMS((void));
+static void popexp PARAMS((void));
+static void expr_unwind PARAMS((void));
+static void expr_bind_variable PARAMS((char *, char *));
+#if defined (ARRAY_VARS)
+static void expr_bind_array_element PARAMS((char *, arrayind_t, char *));
+#endif
+
+static intmax_t subexpr PARAMS((char *));
+
+static intmax_t expcomma PARAMS((void));
+static intmax_t expassign PARAMS((void));
+static intmax_t expcond PARAMS((void));
+static intmax_t explor PARAMS((void));
+static intmax_t expland PARAMS((void));
+static intmax_t expbor PARAMS((void));
+static intmax_t expbxor PARAMS((void));
+static intmax_t expband PARAMS((void));
+static intmax_t exp5 PARAMS((void));
+static intmax_t exp4 PARAMS((void));
+static intmax_t expshift PARAMS((void));
+static intmax_t exp3 PARAMS((void));
+static intmax_t expmuldiv PARAMS((void));
+static intmax_t exppower PARAMS((void));
+static intmax_t exp1 PARAMS((void));
+static intmax_t exp0 PARAMS((void));
/* Global var which contains the stack of expression contexts. */
static EXPR_CONTEXT **expr_stack;
static int expr_depth; /* Location in the stack. */
static int expr_stack_size; /* Number of slots already allocated. */
-extern char *this_command_name;
+#if defined (ARRAY_VARS)
+extern const char * const bash_badsub_errmsg;
+#endif
+
+#define SAVETOK(X) \
+ do { \
+ (X)->curtok = curtok; \
+ (X)->lasttok = lasttok; \
+ (X)->tp = tp; \
+ (X)->lasttp = lasttp; \
+ (X)->tokval = tokval; \
+ (X)->tokstr = tokstr; \
+ (X)->noeval = noeval; \
+ (X)->lval = curlval; \
+ } while (0)
+
+#define RESTORETOK(X) \
+ do { \
+ curtok = (X)->curtok; \
+ lasttok = (X)->lasttok; \
+ tp = (X)->tp; \
+ lasttp = (X)->lasttp; \
+ tokval = (X)->tokval; \
+ tokstr = (X)->tokstr; \
+ noeval = (X)->noeval; \
+ curlval = (X)->lval; \
+ } while (0)
/* Push and save away the contents of the globals describing the
current expression context. */
EXPR_CONTEXT *context;
if (expr_depth >= MAX_EXPR_RECURSION_LEVEL)
- evalerror ("expression recursion level exceeded");
+ evalerror (_("expression recursion level exceeded"));
if (expr_depth >= expr_stack_size)
{
- expr_stack = (EXPR_CONTEXT **)
- xrealloc (expr_stack, (expr_stack_size += EXPR_STACK_GROW_SIZE)
- * sizeof (EXPR_CONTEXT *));
+ expr_stack_size += EXPR_STACK_GROW_SIZE;
+ expr_stack = (EXPR_CONTEXT **)xrealloc (expr_stack, expr_stack_size * sizeof (EXPR_CONTEXT *));
}
context = (EXPR_CONTEXT *)xmalloc (sizeof (EXPR_CONTEXT));
- context->curtok = curtok;
- context->lasttok = lasttok;
context->expression = expression;
- context->tp = tp;
- context->tokval = tokval;
- context->tokstr = tokstr;
+ SAVETOK(context);
+
expr_stack[expr_depth++] = context;
}
{
EXPR_CONTEXT *context;
- if (expr_depth == 0)
- evalerror ("recursion stack underflow");
+ if (expr_depth <= 0)
+ {
+ /* See the comment at the top of evalexp() for an explanation of why
+ this is done. */
+ expression = lasttp = 0;
+ evalerror (_("recursion stack underflow"));
+ }
context = expr_stack[--expr_depth];
- curtok = context->curtok;
- lasttok = context->lasttok;
+
expression = context->expression;
- tp = context->tp;
- tokval = context->tokval;
- tokstr = context->tokstr;
+ RESTORETOK (context);
+
free (context);
}
+static void
+expr_unwind ()
+{
+ while (--expr_depth > 0)
+ {
+ if (expr_stack[expr_depth]->tokstr)
+ free (expr_stack[expr_depth]->tokstr);
+
+ if (expr_stack[expr_depth]->expression)
+ free (expr_stack[expr_depth]->expression);
+
+ free (expr_stack[expr_depth]);
+ }
+ if (expr_depth == 0)
+ free (expr_stack[expr_depth]); /* free the allocated EXPR_CONTEXT */
+
+ noeval = 0; /* XXX */
+}
+
+static void
+expr_bind_variable (lhs, rhs)
+ char *lhs, *rhs;
+{
+ SHELL_VAR *v;
+ int aflags;
+
+ if (lhs == 0 || *lhs == 0)
+ return; /* XXX */
+
+#if defined (ARRAY_VARS)
+ aflags = (assoc_expand_once && already_expanded) ? ASS_NOEXPAND : 0;
+ aflags |= ASS_ALLOWALLSUB; /* allow assoc[@]=value */
+#else
+ aflags = 0;
+#endif
+ v = bind_int_variable (lhs, rhs, aflags);
+ if (v && (readonly_p (v) || noassign_p (v)))
+ sh_longjmp (evalbuf, 1); /* variable assignment error */
+ stupidly_hack_special_variables (lhs);
+}
+
+#if defined (ARRAY_VARS)
+/* This is similar to the logic in arrayfunc.c:valid_array_reference when
+ you pass VA_NOEXPAND. */
+static int
+expr_skipsubscript (vp, cp)
+ char *vp, *cp;
+{
+ int flags, isassoc;
+ SHELL_VAR *entry;
+
+ isassoc = 0;
+ entry = 0;
+ if (assoc_expand_once & already_expanded)
+ {
+ *cp = '\0';
+ isassoc = legal_identifier (vp) && (entry = find_variable (vp)) && assoc_p (entry);
+ *cp = '['; /* ] */
+ }
+ flags = (isassoc && assoc_expand_once && already_expanded) ? VA_NOEXPAND : 0;
+ return (skipsubscript (cp, 0, flags));
+}
+
+/* Rewrite tok, which is of the form vname[expression], to vname[ind], where
+ IND is the already-calculated value of expression. */
+static void
+expr_bind_array_element (tok, ind, rhs)
+ char *tok;
+ arrayind_t ind;
+ char *rhs;
+{
+ char *lhs, *vname;
+ size_t llen;
+ char ibuf[INT_STRLEN_BOUND (arrayind_t) + 1], *istr;
+
+ istr = fmtumax (ind, 10, ibuf, sizeof (ibuf), 0);
+ vname = array_variable_name (tok, 0, (char **)NULL, (int *)NULL);
+
+ llen = strlen (vname) + sizeof (ibuf) + 3;
+ lhs = xmalloc (llen);
+
+ sprintf (lhs, "%s[%s]", vname, istr); /* XXX */
+
+/*itrace("expr_bind_array_element: %s=%s", lhs, rhs);*/
+ expr_bind_variable (lhs, rhs);
+ free (vname);
+ free (lhs);
+}
+#endif /* ARRAY_VARS */
+
/* Evaluate EXPR, and return the arithmetic result. If VALIDP is
non-null, a zero is stored into the location to which it points
if the expression is invalid, non-zero otherwise. If a non-zero
were assigned at program startup or by the compiler. Therefore, it is
safe to let the loop terminate when expr_depth == 0, without freeing up
any of the expr_depth[0] stuff. */
-long
-evalexp (expr, validp)
+intmax_t
+evalexp (expr, flags, validp)
char *expr;
+ int flags;
int *validp;
{
- long val;
-#if 0
- procenv_t old_evalbuf;
-#endif
+ intmax_t val;
+ int c;
+ procenv_t oevalbuf;
- val = 0L;
+ val = 0;
+ noeval = 0;
+ already_expanded = (flags&EXP_EXPANDED);
-#if 0
- /* Save the value of evalbuf to protect it around possible recursive
- calls to evalexp (). */
- COPY_PROCENV (evalbuf, old_evalbuf);
-#endif
+ FASTCOPY (evalbuf, oevalbuf, sizeof (evalbuf));
+
+ c = setjmp_nosigs (evalbuf);
- if (setjmp (evalbuf))
+ if (c)
{
FREE (tokstr);
FREE (expression);
tokstr = expression = (char *)NULL;
- while (--expr_depth > 0)
- {
- if (expr_stack[expr_depth]->tokstr)
- free (expr_stack[expr_depth]->tokstr);
+ expr_unwind ();
+ expr_depth = 0; /* XXX - make sure */
- if (expr_stack[expr_depth]->expression)
- free (expr_stack[expr_depth]->expression);
-
- free (expr_stack[expr_depth]);
- }
- free (expr_stack[expr_depth]); /* free the allocated EXPR_CONTEXT */
+ /* We copy in case we've called evalexp recursively */
+ FASTCOPY (oevalbuf, evalbuf, sizeof (evalbuf));
if (validp)
*validp = 0;
- return (0L);
+ return (0);
}
val = subexpr (expr);
-#if 0
- /* Restore the value of evalbuf so that any subsequent longjmp calls
- will have a valid location to jump to. */
- COPY_PROCENV (old_evalbuf, evalbuf);
-#endif
-
if (validp)
*validp = 1;
+ FASTCOPY (oevalbuf, evalbuf, sizeof (evalbuf));
+
return (val);
}
-static long
+static intmax_t
subexpr (expr)
char *expr;
{
- long val;
+ intmax_t val;
char *p;
for (p = expr; p && *p && cr_whitespace (*p); p++)
;
if (p == NULL || *p == '\0')
- return (0L);
+ return (0);
pushexp ();
- curtok = lasttok = 0;
expression = savestring (expr);
tp = expression;
+ curtok = lasttok = 0;
tokstr = (char *)NULL;
- tokval = 0L;
+ tokval = 0;
+ init_lvalue (&curlval);
+ lastlval = curlval;
readtok ();
- val = expassign ();
+ val = EXP_LOWEST ();
+ /*TAG:bash-5.3 make it clear that these are arithmetic syntax errors */
if (curtok != 0)
- evalerror ("syntax error in expression");
+ evalerror (_("syntax error in expression"));
FREE (tokstr);
FREE (expression);
return val;
}
-/* Bind/create a shell variable with the name LHS to the RHS.
- This creates or modifies a variable such that it is an integer.
-
- This should really be in variables.c, but it is here so that all of the
- expression evaluation stuff is localized. Since we don't want any
- recursive evaluation from bind_variable() (possible without this code,
- since bind_variable() calls the evaluator for variables with the integer
- attribute set), we temporarily turn off the integer attribute for each
- variable we set here, then turn it back on after binding as necessary. */
-
-void
-bind_int_variable (lhs, rhs)
- char *lhs, *rhs;
+static intmax_t
+expcomma ()
{
- register SHELL_VAR *v;
- int isint = 0;
+ register intmax_t value;
- v = find_variable (lhs);
- if (v)
+ value = expassign ();
+ while (curtok == COMMA)
{
- isint = integer_p (v);
- v->attributes &= ~att_integer;
+ readtok ();
+ value = expassign ();
}
- v = bind_variable (lhs, rhs);
- if (isint)
- v->attributes |= att_integer;
+ return value;
}
-
-static long
+
+static intmax_t
expassign ()
{
- register long value;
+ register intmax_t value;
char *lhs, *rhs;
+ arrayind_t lind;
+#if defined (HAVE_IMAXDIV)
+ imaxdiv_t idiv;
+#endif
value = expcond ();
if (curtok == EQ || curtok == OP_ASSIGN)
{
int special, op;
- long lvalue;
+ intmax_t lvalue;
special = curtok == OP_ASSIGN;
if (lasttok != STR)
- evalerror ("attempted assignment to non-variable");
+ evalerror (_("attempted assignment to non-variable"));
if (special)
{
lvalue = value;
}
+ if (tokstr == 0)
+ evalerror (_("syntax error in variable assignment"));
+
+ /* XXX - watch out for pointer aliasing issues here */
lhs = savestring (tokstr);
+ /* save ind in case rhs is string var and evaluation overwrites it */
+ lind = curlval.ind;
readtok ();
value = expassign ();
if (special)
{
+ if ((op == DIV || op == MOD) && value == 0)
+ {
+ if (noeval == 0)
+ evalerror (_("division by 0"));
+ else
+ value = 1;
+ }
+
switch (op)
{
case MUL:
+ /* Handle INTMAX_MIN and INTMAX_MAX * -1 specially here? */
lvalue *= value;
break;
case DIV:
- lvalue /= value;
- break;
case MOD:
- lvalue %= value;
+ if (lvalue == INTMAX_MIN && value == -1)
+ lvalue = (op == DIV) ? INTMAX_MIN : 0;
+ else
+#if HAVE_IMAXDIV
+ {
+ idiv = imaxdiv (lvalue, value);
+ lvalue = (op == DIV) ? idiv.quot : idiv.rem;
+ }
+#else
+ lvalue = (op == DIV) ? lvalue / value : lvalue % value;
+#endif
break;
case PLUS:
lvalue += value;
case BOR:
lvalue |= value;
break;
+ case BXOR:
+ lvalue ^= value;
+ break;
default:
free (lhs);
- evalerror ("bug: bad expassign token");
+ evalerror (_("bug: bad expassign token"));
break;
}
value = lvalue;
rhs = itos (value);
if (noeval == 0)
- bind_int_variable (lhs, rhs);
+ {
+#if defined (ARRAY_VARS)
+ if (lind != -1)
+ expr_bind_array_element (lhs, lind, rhs);
+ else
+#endif
+ expr_bind_variable (lhs, rhs);
+ }
+ if (curlval.tokstr && curlval.tokstr == tokstr)
+ init_lvalue (&curlval);
+
free (rhs);
free (lhs);
FREE (tokstr);
tokstr = (char *)NULL; /* For freeing on errors. */
}
+
return (value);
}
/* Conditional expression (expr?expr:expr) */
-static long
+static intmax_t
expcond ()
{
- long cval, val1, val2, rval;
+ intmax_t cval, val1, val2, rval;
int set_noeval;
set_noeval = 0;
rval = cval = explor ();
if (curtok == QUES) /* found conditional expr */
{
- readtok ();
- if (curtok == 0 || curtok == COL)
- evalerror ("expression expected");
if (cval == 0)
{
set_noeval = 1;
noeval++;
}
-#if 0
- val1 = explor ();
-#else
- val1 = expassign ();
-#endif
+
+ readtok ();
+ if (curtok == 0 || curtok == COL)
+ evalerror (_("expression expected"));
+
+ val1 = EXP_LOWEST ();
+
if (set_noeval)
- noeval--;
+ noeval--;
if (curtok != COL)
- evalerror ("`:' expected for conditional expression");
- readtok ();
- if (curtok == 0)
- evalerror ("expression expected");
+ evalerror (_("`:' expected for conditional expression"));
+
set_noeval = 0;
if (cval)
{
set_noeval = 1;
noeval++;
}
- val2 = explor ();
+
+ readtok ();
+ if (curtok == 0)
+ evalerror (_("expression expected"));
+ val2 = expcond ();
+
if (set_noeval)
- noeval--;
+ noeval--;
rval = cval ? val1 : val2;
lasttok = COND;
}
}
/* Logical OR. */
-static long
+static intmax_t
explor ()
{
- register long val1, val2;
+ register intmax_t val1, val2;
int set_noeval;
val1 = expland ();
}
/* Logical AND. */
-static long
+static intmax_t
expland ()
{
- register long val1, val2;
+ register intmax_t val1, val2;
int set_noeval;
val1 = expbor ();
}
/* Bitwise OR. */
-static long
+static intmax_t
expbor ()
{
- register long val1, val2;
+ register intmax_t val1, val2;
val1 = expbxor ();
readtok ();
val2 = expbxor ();
val1 = val1 | val2;
+ lasttok = NUM;
}
return (val1);
}
/* Bitwise XOR. */
-static long
+static intmax_t
expbxor ()
{
- register long val1, val2;
+ register intmax_t val1, val2;
val1 = expband ();
readtok ();
val2 = expband ();
val1 = val1 ^ val2;
+ lasttok = NUM;
}
return (val1);
}
/* Bitwise AND. */
-static long
+static intmax_t
expband ()
{
- register long val1, val2;
+ register intmax_t val1, val2;
val1 = exp5 ();
readtok ();
val2 = exp5 ();
val1 = val1 & val2;
+ lasttok = NUM;
}
return (val1);
}
-static long
+static intmax_t
exp5 ()
{
- register long val1, val2;
+ register intmax_t val1, val2;
val1 = exp4 ();
val1 = (val1 == val2);
else if (op == NEQ)
val1 = (val1 != val2);
+ lasttok = NUM;
}
return (val1);
}
-static long
+static intmax_t
exp4 ()
{
- register long val1, val2;
+ register intmax_t val1, val2;
val1 = expshift ();
while ((curtok == LEQ) ||
val1 = val1 < val2;
else /* (op == GT) */
val1 = val1 > val2;
+ lasttok = NUM;
}
return (val1);
}
/* Left and right shifts. */
-static long
+static intmax_t
expshift ()
{
- register long val1, val2;
+ register intmax_t val1, val2;
val1 = exp3 ();
val1 = val1 << val2;
else
val1 = val1 >> val2;
+ lasttok = NUM;
}
return (val1);
}
-static long
+static intmax_t
exp3 ()
{
- register long val1, val2;
+ register intmax_t val1, val2;
- val1 = exp2 ();
+ val1 = expmuldiv ();
while ((curtok == PLUS) || (curtok == MINUS))
{
int op = curtok;
readtok ();
- val2 = exp2 ();
+ val2 = expmuldiv ();
if (op == PLUS)
val1 += val2;
else if (op == MINUS)
val1 -= val2;
+ lasttok = NUM;
}
return (val1);
}
-static long
-exp2 ()
+static intmax_t
+expmuldiv ()
{
- register long val1, val2;
+ register intmax_t val1, val2;
+#if defined (HAVE_IMAXDIV)
+ imaxdiv_t idiv;
+#endif
val1 = exppower ();
while ((curtok == MUL) ||
- (curtok == DIV) ||
- (curtok == MOD))
+ (curtok == DIV) ||
+ (curtok == MOD))
{
int op = curtok;
+ char *stp, *sltp;
+ stp = tp;
readtok ();
val2 = exppower ();
+ /* Handle division by 0 and twos-complement arithmetic overflow */
if (((op == DIV) || (op == MOD)) && (val2 == 0))
- evalerror ("division by 0");
+ {
+ if (noeval == 0)
+ {
+ sltp = lasttp;
+ lasttp = stp;
+ while (lasttp && *lasttp && whitespace (*lasttp))
+ lasttp++;
+ evalerror (_("division by 0"));
+ lasttp = sltp;
+ }
+ else
+ val2 = 1;
+ }
+ else if (op == MOD && val1 == INTMAX_MIN && val2 == -1)
+ {
+ val1 = 0;
+ continue;
+ }
+ else if (op == DIV && val1 == INTMAX_MIN && val2 == -1)
+ val2 = 1;
if (op == MUL)
- val1 *= val2;
- else if (op == DIV)
- val1 /= val2;
- else if (op == MOD)
- val1 %= val2;
+ val1 *= val2;
+ else if (op == DIV || op == MOD)
+#if defined (HAVE_IMAXDIV)
+ {
+ idiv = imaxdiv (val1, val2);
+ val1 = (op == DIV) ? idiv.quot : idiv.rem;
+ }
+#else
+ val1 = (op == DIV) ? val1 / val2 : val1 % val2;
+#endif
+ lasttok = NUM;
}
return (val1);
}
-static long
+static intmax_t
+ipow (base, exp)
+ intmax_t base, exp;
+{
+ intmax_t result;
+
+ result = 1;
+ while (exp)
+ {
+ if (exp & 1)
+ result *= base;
+ exp >>= 1;
+ base *= base;
+ }
+ return result;
+}
+
+static intmax_t
exppower ()
{
- register long val1, val2, c;
+ register intmax_t val1, val2, c;
val1 = exp1 ();
- if (curtok == POWER)
+ while (curtok == POWER)
{
readtok ();
- val2 = exp1 ();
+ val2 = exppower (); /* exponentiation is right-associative */
+ lasttok = NUM;
if (val2 == 0)
- return (1L);
- for (c = 1; val2--; c *= val1)
- ;
- val1 = c;
+ return (1);
+ if (val2 < 0)
+ evalerror (_("exponent less than 0"));
+ val1 = ipow (val1, val2);
}
return (val1);
}
-static long
+static intmax_t
exp1 ()
{
- register long val;
+ register intmax_t val;
if (curtok == NOT)
{
readtok ();
val = !exp1 ();
+ lasttok = NUM;
}
else if (curtok == BNOT)
{
readtok ();
val = ~exp1 ();
+ lasttok = NUM;
+ }
+ else if (curtok == MINUS)
+ {
+ readtok ();
+ val = - exp1 ();
+ lasttok = NUM;
+ }
+ else if (curtok == PLUS)
+ {
+ readtok ();
+ val = exp1 ();
+ lasttok = NUM;
}
else
val = exp0 ();
return (val);
}
-static long
+static intmax_t
exp0 ()
{
- register long val = 0L;
-
- if (curtok == MINUS)
+ register intmax_t val = 0, v2;
+ char *vincdec;
+ int stok;
+ EXPR_CONTEXT ec;
+
+ /* XXX - might need additional logic here to decide whether or not
+ pre-increment or pre-decrement is legal at this point. */
+ if (curtok == PREINC || curtok == PREDEC)
{
+ stok = lasttok = curtok;
readtok ();
- val = - exp0 ();
- }
- else if (curtok == PLUS)
- {
+ if (curtok != STR)
+ /* readtok() catches this */
+ evalerror (_("identifier expected after pre-increment or pre-decrement"));
+
+ v2 = tokval + ((stok == PREINC) ? 1 : -1);
+ vincdec = itos (v2);
+ if (noeval == 0)
+ {
+#if defined (ARRAY_VARS)
+ if (curlval.ind != -1)
+ expr_bind_array_element (curlval.tokstr, curlval.ind, vincdec);
+ else
+#endif
+ if (tokstr)
+ expr_bind_variable (tokstr, vincdec);
+ }
+ free (vincdec);
+ val = v2;
+
+ curtok = NUM; /* make sure --x=7 is flagged as an error */
readtok ();
- val = exp0 ();
}
else if (curtok == LPAR)
{
+ /* XXX - save curlval here? Or entire expression context? */
readtok ();
- val = expassign ();
+ val = EXP_LOWEST ();
- if (curtok != RPAR)
- evalerror ("missing `)'");
+ if (curtok != RPAR) /* ( */
+ evalerror (_("missing `)'"));
/* Skip over closing paren. */
readtok ();
else if ((curtok == NUM) || (curtok == STR))
{
val = tokval;
+ if (curtok == STR)
+ {
+ SAVETOK (&ec);
+ tokstr = (char *)NULL; /* keep it from being freed */
+ noeval = 1;
+ readtok ();
+ stok = curtok;
+
+ /* post-increment or post-decrement */
+ if (stok == POSTINC || stok == POSTDEC)
+ {
+ /* restore certain portions of EC */
+ tokstr = ec.tokstr;
+ noeval = ec.noeval;
+ curlval = ec.lval;
+ lasttok = STR; /* ec.curtok */
+
+ v2 = val + ((stok == POSTINC) ? 1 : -1);
+ vincdec = itos (v2);
+ if (noeval == 0)
+ {
+#if defined (ARRAY_VARS)
+ if (curlval.ind != -1)
+ expr_bind_array_element (curlval.tokstr, curlval.ind, vincdec);
+ else
+#endif
+ expr_bind_variable (tokstr, vincdec);
+ }
+ free (vincdec);
+ curtok = NUM; /* make sure x++=7 is flagged as an error */
+ }
+ else
+ {
+ /* XXX - watch out for pointer aliasing issues here */
+ if (stok == STR) /* free new tokstr before old one is restored */
+ FREE (tokstr);
+ RESTORETOK (&ec);
+ }
+ }
+
readtok ();
}
else
- evalerror ("syntax error: operand expected");
+ evalerror (_("syntax error: operand expected"));
return (val);
}
+static void
+init_lvalue (lv)
+ struct lvalue *lv;
+{
+ lv->tokstr = 0;
+ lv->tokvar = 0;
+ lv->tokval = lv->ind = -1;
+}
+
+static struct lvalue *
+alloc_lvalue ()
+{
+ struct lvalue *lv;
+
+ lv = xmalloc (sizeof (struct lvalue));
+ init_lvalue (lv);
+ return (lv);
+}
+
+static void
+free_lvalue (lv)
+ struct lvalue *lv;
+{
+ free (lv); /* should be inlined */
+}
+
+static intmax_t
+expr_streval (tok, e, lvalue)
+ char *tok;
+ int e;
+ struct lvalue *lvalue;
+{
+ SHELL_VAR *v;
+ char *value;
+ intmax_t tval;
+ int initial_depth;
+#if defined (ARRAY_VARS)
+ arrayind_t ind;
+ int tflag, aflag;
+ array_eltstate_t es;
+#endif
+
+/*itrace("expr_streval: %s: noeval = %d expanded=%d", tok, noeval, already_expanded);*/
+ /* If we are suppressing evaluation, just short-circuit here instead of
+ going through the rest of the evaluator. */
+ if (noeval)
+ return (0);
+
+ initial_depth = expr_depth;
+
+#if defined (ARRAY_VARS)
+ tflag = (assoc_expand_once && already_expanded) ? AV_NOEXPAND : 0; /* for a start */
+#endif
+
+ /* [[[[[ */
+#if defined (ARRAY_VARS)
+ aflag = tflag; /* use a different variable for now */
+ if (shell_compatibility_level > 51)
+ aflag |= AV_ATSTARKEYS;
+ v = (e == ']') ? array_variable_part (tok, tflag, (char **)0, (int *)0) : find_variable (tok);
+#else
+ v = find_variable (tok);
+#endif
+ if (v == 0 && e != ']')
+ v = find_variable_last_nameref (tok, 0);
+
+ if ((v == 0 || invisible_p (v)) && unbound_vars_is_error)
+ {
+#if defined (ARRAY_VARS)
+ value = (e == ']') ? array_variable_name (tok, tflag, (char **)0, (int *)0) : tok;
+#else
+ value = tok;
+#endif
+
+ set_exit_status (EXECUTION_FAILURE);
+ err_unboundvar (value);
+
+#if defined (ARRAY_VARS)
+ if (e == ']')
+ FREE (value); /* array_variable_name returns new memory */
+#endif
+
+ if (no_longjmp_on_fatal_error && interactive_shell)
+ sh_longjmp (evalbuf, 1);
+
+ if (interactive_shell)
+ {
+ expr_unwind ();
+ top_level_cleanup ();
+ jump_to_top_level (DISCARD);
+ }
+ else
+ jump_to_top_level (FORCE_EOF);
+ }
+
+#if defined (ARRAY_VARS)
+ init_eltstate (&es);
+ es.ind = -1;
+ /* If the second argument to get_array_value doesn't include AV_ALLOWALL,
+ we don't allow references like array[@]. In this case, get_array_value
+ is just like get_variable_value in that it does not return newly-allocated
+ memory or quote the results. AFLAG is set above and is either AV_NOEXPAND
+ or 0. */
+ value = (e == ']') ? get_array_value (tok, aflag, &es) : get_variable_value (v);
+ ind = es.ind;
+ flush_eltstate (&es);
+#else
+ value = get_variable_value (v);
+#endif
+
+ if (expr_depth < initial_depth)
+ {
+ if (no_longjmp_on_fatal_error && interactive_shell)
+ sh_longjmp (evalbuf, 1);
+ return (0);
+ }
+
+ tval = (value && *value) ? subexpr (value) : 0;
+
+ if (lvalue)
+ {
+ lvalue->tokstr = tok; /* XXX */
+ lvalue->tokval = tval;
+ lvalue->tokvar = v; /* XXX */
+#if defined (ARRAY_VARS)
+ lvalue->ind = ind;
+#else
+ lvalue->ind = -1;
+#endif
+ }
+
+ return (tval);
+}
+
+static int
+_is_multiop (c)
+ int c;
+{
+ switch (c)
+ {
+ case EQEQ:
+ case NEQ:
+ case LEQ:
+ case GEQ:
+ case LAND:
+ case LOR:
+ case LSH:
+ case RSH:
+ case OP_ASSIGN:
+ case COND:
+ case POWER:
+ case PREINC:
+ case PREDEC:
+ case POSTINC:
+ case POSTDEC:
+ return 1;
+ default:
+ return 0;
+ }
+}
+
+static int
+_is_arithop (c)
+ int c;
+{
+ switch (c)
+ {
+ case EQ:
+ case GT:
+ case LT:
+ case PLUS:
+ case MINUS:
+ case MUL:
+ case DIV:
+ case MOD:
+ case NOT:
+ case LPAR:
+ case RPAR:
+ case BAND:
+ case BOR:
+ case BXOR:
+ case BNOT:
+ return 1; /* operator tokens */
+ case QUES:
+ case COL:
+ case COMMA:
+ return 1; /* questionable */
+ default:
+ return 0; /* anything else is invalid */
+ }
+}
+
/* Lexical analyzer/token reader for the expression evaluator. Reads the
next token and puts its value into curtok, while advancing past it.
Updates value of tp. May also set tokval (for number) or tokstr (for
static void
readtok ()
{
- register char *cp;
- register int c, c1, e;
+ register char *cp, *xp;
+ register unsigned char c, c1;
+ register int e;
+ struct lvalue lval;
/* Skip leading whitespace. */
cp = tp;
if (c)
cp++;
- lasttp = tp = cp - 1;
-
if (c == '\0')
{
lasttok = curtok;
tp = cp;
return;
}
+ lasttp = tp = cp - 1;
if (legal_variable_starter (c))
{
- /* Semi-bogus ksh compatibility feature -- variable names
- not preceded with a dollar sign are shell variables. */
- char *value;
+ /* variable names not preceded with a dollar sign are shell variables. */
+ char *savecp;
+ EXPR_CONTEXT ec;
+ int peektok;
while (legal_variable_char (c))
c = *cp++;
#if defined (ARRAY_VARS)
if (c == '[')
{
- e = skipsubscript (cp, 0);
+ e = expr_skipsubscript (tp, cp); /* XXX - was skipsubscript */
if (cp[e] == ']')
{
cp += e + 1;
e = ']';
}
else
- evalerror ("bad array subscript");
+ evalerror (bash_badsub_errmsg);
}
#endif /* ARRAY_VARS */
*cp = '\0';
+ /* XXX - watch out for pointer aliasing issues here */
+ if (curlval.tokstr && curlval.tokstr == tokstr)
+ init_lvalue (&curlval);
FREE (tokstr);
tokstr = savestring (tp);
+ *cp = c;
-#if defined (ARRAY_VARS)
- value = (e == ']') ? get_array_value (tokstr, 0) : get_string_value (tokstr);
-#else
- value = get_string_value (tokstr);
-#endif
-
- tokval = (value && *value) ? subexpr (value) : 0;
-
-#if defined (ARRAY_VARS)
- if (e == ']')
- FREE (value); /* get_array_value returns newly-allocated memory */
-#endif
+ /* XXX - make peektok part of saved token state? */
+ SAVETOK (&ec);
+ tokstr = (char *)NULL; /* keep it from being freed */
+ tp = savecp = cp;
+ noeval = 1;
+ curtok = STR;
+ readtok ();
+ peektok = curtok;
+ if (peektok == STR) /* free new tokstr before old one is restored */
+ FREE (tokstr);
+ RESTORETOK (&ec);
+ cp = savecp;
+
+ /* The tests for PREINC and PREDEC aren't strictly correct, but they
+ preserve old behavior if a construct like --x=9 is given. */
+ if (lasttok == PREINC || lasttok == PREDEC || peektok != EQ)
+ {
+ lastlval = curlval;
+ tokval = expr_streval (tokstr, e, &curlval);
+ }
+ else
+ tokval = 0;
- *cp = c;
lasttok = curtok;
curtok = STR;
}
- else if (digit(c))
+ else if (DIGIT(c))
{
- while (digit (c) || isletter (c) || c == '#' || c == '@' || c == '_')
+ while (ISALNUM (c) || c == '#' || c == '@' || c == '_')
c = *cp++;
c = *--cp;
else if ((c == BOR) && (c1 == BOR))
c = LOR;
else if ((c == '*') && (c1 == '*'))
- c = POWER;
- else if (c1 == EQ && member(c, "*/%+-&^|"))
+ c = POWER;
+ else if ((c == '-' || c == '+') && c1 == c && curtok == STR)
+ c = (c == '-') ? POSTDEC : POSTINC;
+#if STRICT_ARITH_PARSING
+ else if ((c == '-' || c == '+') && c1 == c && curtok == NUM)
+#else
+ else if ((c == '-' || c == '+') && c1 == c && curtok == NUM && (lasttok == PREINC || lasttok == PREDEC))
+#endif
+ {
+ /* This catches something like --FOO++ */
+ /* TAG:bash-5.3 add gettext calls here or make this a separate function */
+ if (c == '-')
+ evalerror ("--: assignment requires lvalue");
+ else
+ evalerror ("++: assignment requires lvalue");
+ }
+ else if ((c == '-' || c == '+') && c1 == c)
+ {
+ /* Quickly scan forward to see if this is followed by optional
+ whitespace and an identifier. */
+ xp = cp;
+ while (xp && *xp && cr_whitespace (*xp))
+ xp++;
+ if (legal_variable_starter ((unsigned char)*xp))
+ c = (c == '-') ? PREDEC : PREINC;
+ else
+ /* Could force parsing as preinc or predec and throw an error */
+#if STRICT_ARITH_PARSING
+ {
+ /* Posix says unary plus and minus have higher priority than
+ preinc and predec. */
+ /* This catches something like --4++ */
+ if (c == '-')
+ evalerror ("--: assignment requires lvalue");
+ else
+ evalerror ("++: assignment requires lvalue");
+ }
+#else
+ cp--; /* not preinc or predec, so unget the character */
+#endif
+ }
+ else if (c1 == EQ && member (c, "*/%+-&^|"))
{
assigntok = c; /* a OP= b */
c = OP_ASSIGN;
}
+ else if (_is_arithop (c) == 0)
+ {
+ cp--;
+ /* use curtok, since it hasn't been copied to lasttok yet */
+ if (curtok == 0 || _is_arithop (curtok) || _is_multiop (curtok))
+ evalerror (_("syntax error: operand expected"));
+ else
+ evalerror (_("syntax error: invalid arithmetic operator"));
+ }
else
cp--; /* `unget' the character */
+
+ /* Should check here to make sure that the current character is one
+ of the recognized operators and flag an error if not. Could create
+ a character map the first time through and check it on subsequent
+ calls. */
lasttok = curtok;
curtok = c;
}
static void
evalerror (msg)
- char *msg;
+ const char *msg;
{
char *name, *t;
name = this_command_name;
- for (t = expression; whitespace (*t); t++)
+ for (t = expression; t && whitespace (*t); t++)
;
- internal_error ("%s%s%s: %s (error token is \"%s\")",
- name ? name : "", name ? ": " : "", t,
- msg, (lasttp && *lasttp) ? lasttp : "");
- longjmp (evalbuf, 1);
+ internal_error (_("%s%s%s: %s (error token is \"%s\")"),
+ name ? name : "", name ? ": " : "",
+ t ? t : "", msg, (lasttp && *lasttp) ? lasttp : "");
+ sh_longjmp (evalbuf, 1);
}
-/* Convert a string to a long integer, with an arbitrary base.
+/* Convert a string to an intmax_t integer, with an arbitrary base.
0nnn -> base 8
0[Xx]nn -> base 16
Anything else: [base#]number (this is implemented to match ksh93)
Base may be >=2 and <=64. If base is <= 36, the numbers are drawn
from [0-9][a-zA-Z], and lowercase and uppercase letters may be used
- interchangably. If base is > 36 and <= 64, the numbers are drawn
- from [0-9][a-z][A-Z]_@ (a = 10, z = 35, A = 36, Z = 61, _ = 62, @ = 63 --
+ interchangeably. If base is > 36 and <= 64, the numbers are drawn
+ from [0-9][a-z][A-Z]_@ (a = 10, z = 35, A = 36, Z = 61, @ = 62, _ = 63 --
you get the picture). */
-static long
+#define VALID_NUMCHAR(c) (ISALNUM(c) || ((c) == '_') || ((c) == '@'))
+
+static intmax_t
strlong (num)
char *num;
{
register char *s;
- register int c;
+ register unsigned char c;
int base, foundbase;
- long val = 0L;
+ intmax_t val, pval;
s = num;
- if (s == NULL || *s == '\0')
- return 0L;
base = 10;
foundbase = 0;
{
s++;
- if (s == NULL || *s == '\0')
- return 0L;
+ if (*s == '\0')
+ return 0;
/* Base 16? */
if (*s == 'x' || *s == 'X')
{
base = 16;
s++;
+#if STRICT_ARITH_PARSING
+ if (*s == 0)
+ evalerror (_("invalid number"));
+#endif
}
else
base = 8;
foundbase++;
}
- val = 0L;
+ val = 0;
for (c = *s++; c; c = *s++)
{
if (c == '#')
{
if (foundbase)
- evalerror ("bad number");
-
- base = (int)val;
+ evalerror (_("invalid number"));
/* Illegal base specifications raise an evaluation error. */
- if (base < 2 || base > 64)
- evalerror ("illegal arithmetic base");
+ if (val < 2 || val > 64)
+ evalerror (_("invalid arithmetic base"));
- val = 0L;
+ base = val;
+ val = 0;
foundbase++;
+
+ /* Make sure a base# is followed by a character that can compose a
+ valid integer constant. Jeremy Townshend <jeremy.townshend@gmail.com> */
+ if (VALID_NUMCHAR (*s) == 0)
+ evalerror (_("invalid integer constant"));
}
- else if (isletter(c) || digit(c) || (c == '_') || (c == '@'))
+ else if (VALID_NUMCHAR (c))
{
- if (digit(c))
- c = digit_value(c);
+ if (DIGIT(c))
+ c = TODIGIT(c);
else if (c >= 'a' && c <= 'z')
c -= 'a' - 10;
else if (c >= 'A' && c <= 'Z')
c -= 'A' - ((base <= 36) ? 10 : 36);
- else if (c == '_')
- c = 62;
else if (c == '@')
+ c = 62;
+ else if (c == '_')
c = 63;
if (c >= base)
- evalerror ("value too great for base");
+ evalerror (_("value too great for base"));
+#ifdef CHECK_OVERFLOW
+ pval = val;
+ val = (val * base) + c;
+ if (val < 0 || val < pval) /* overflow */
+ return INTMAX_MAX;
+#else
val = (val * base) + c;
+#endif
}
else
break;
}
+
return (val);
}
#if defined (EXPR_TEST)
-char *
+void *
xmalloc (n)
int n;
{
return (malloc (n));
}
-char *
+void *
xrealloc (s, n)
char *s;
int n;
char **argv;
{
register int i;
- long v;
+ intmax_t v;
int expok;
if (setjmp (top_level))
for (i = 1; i < argc; i++)
{
- v = evalexp (argv[i], &expok);
+ v = evalexp (argv[i], 0, &expok);
if (expok == 0)
- fprintf (stderr, "%s: expression error\n", argv[i]);
+ fprintf (stderr, _("%s: expression error\n"), argv[i]);
else
- printf ("'%s' -> %ld\n", argv[i], v);
+ printf ("'%s' -> %ld\n", argv[i], v);
}
exit (0);
}
char *
itos (n)
- int n;
+ intmax_t n;
{
return ("42");
}
projects / thirdparty / bash.git / blobdiff