/* expr.c -- arithmetic expression evaluation. */
-/* Copyright (C) 1990, 1991 Free Software Foundation, Inc.
+/* Copyright (C) 1990-2009 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 2, 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, 59 Temple Place, Suite 330, Boston, MA 02111 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
"||"
"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
#endif
#include "chartypes.h"
+#include "bashintl.h"
#include "shell.h"
static int lasttok; /* the previous token */
static int assigntok; /* the OP in OP= */
static char *tokstr; /* current token string */
-static long 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 int _is_arithop __P((int));
static void readtok __P((void)); /* lexical analyzer */
-static long strlong __P((char *));
-static void evalerror __P((char *));
+
+static intmax_t expr_streval __P((char *, int));
+static intmax_t strlong __P((char *));
+static void evalerror __P((const char *));
static void pushexp __P((void));
static void popexp __P((void));
-
-static long subexpr __P((char *));
-
-static long expcomma __P((void));
-static long expassign __P((void));
-static long expcond __P((void));
-static long explor __P((void));
-static long expland __P((void));
-static long expbor __P((void));
-static long expbxor __P((void));
-static long expband __P((void));
-static long exp5 __P((void));
-static long exp4 __P((void));
-static long expshift __P((void));
-static long exp3 __P((void));
-static long exp2 __P((void));
-static long exppower __P((void));
-static long exp1 __P((void));
-static long exp0 __P((void));
+static void expr_unwind __P((void));
+static void expr_bind_variable __P((char *, char *));
+
+static intmax_t subexpr __P((char *));
+
+static intmax_t expcomma __P((void));
+static intmax_t expassign __P((void));
+static intmax_t expcond __P((void));
+static intmax_t explor __P((void));
+static intmax_t expland __P((void));
+static intmax_t expbor __P((void));
+static intmax_t expbxor __P((void));
+static intmax_t expband __P((void));
+static intmax_t exp5 __P((void));
+static intmax_t exp4 __P((void));
+static intmax_t expshift __P((void));
+static intmax_t exp3 __P((void));
+static intmax_t exp2 __P((void));
+static intmax_t exppower __P((void));
+static intmax_t exp1 __P((void));
+static intmax_t exp0 __P((void));
/* A structure defining a single expression context. */
typedef struct {
int curtok, lasttok;
char *expression, *tp, *lasttp;
- long tokval;
+ intmax_t tokval;
char *tokstr;
int noeval;
} EXPR_CONTEXT;
/* Not used yet. */
typedef struct {
char *tokstr;
- long tokval;
+ intmax_t tokval;
} LVALUE;
#endif
static int expr_stack_size; /* Number of slots already allocated. */
extern char *this_command_name;
+extern int unbound_vars_is_error;
+
+#if defined (ARRAY_VARS)
+extern const char * const bash_badsub_errmsg;
+#endif
#define SAVETOK(X) \
do { \
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_CONTEXT *context;
if (expr_depth == 0)
- evalerror ("recursion stack underflow");
+ evalerror (_("recursion stack underflow"));
context = expr_stack[--expr_depth];
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]);
+ }
+ free (expr_stack[expr_depth]); /* free the allocated EXPR_CONTEXT */
+
+ noeval = 0; /* XXX */
+}
+
+static void
+expr_bind_variable (lhs, rhs)
+ char *lhs, *rhs;
+{
+ (void)bind_int_variable (lhs, rhs);
+ stupidly_hack_special_variables (lhs);
+}
+
/* 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
+intmax_t
evalexp (expr, validp)
char *expr;
int *validp;
{
- long val;
-#if 0
- procenv_t old_evalbuf;
-#endif
+ intmax_t val;
+ int c;
+ procenv_t oevalbuf;
val = 0;
+ noeval = 0;
-#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));
- if (setjmp (evalbuf))
+ c = 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);
-
- 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 */
+ expr_unwind ();
if (validp)
*validp = 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++)
val = EXP_HIGHEST ();
if (curtok != 0)
- evalerror ("syntax error in expression");
+ evalerror (_("syntax error in expression"));
FREE (tokstr);
FREE (expression);
return val;
}
-static long
+static intmax_t
expcomma ()
{
- register long value;
+ register intmax_t value;
value = expassign ();
while (curtok == COMMA)
return value;
}
-static long
+static intmax_t
expassign ()
{
- register long value;
+ register intmax_t value;
char *lhs, *rhs;
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;
break;
case DIV:
+ if (value == 0)
+ evalerror (_("division by 0"));
lvalue /= value;
break;
case MOD:
+ if (value == 0)
+ evalerror (_("division by 0"));
lvalue %= value;
break;
case PLUS:
break;
default:
free (lhs);
- evalerror ("bug: bad expassign token");
+ evalerror (_("bug: bad expassign token"));
break;
}
value = lvalue;
rhs = itos (value);
if (noeval == 0)
- (void)bind_int_variable (lhs, rhs);
+ expr_bind_variable (lhs, rhs);
free (rhs);
free (lhs);
FREE (tokstr);
}
/* 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;
{
readtok ();
if (curtok == 0 || curtok == COL)
- evalerror ("expression expected");
+ evalerror (_("expression expected"));
if (cval == 0)
{
set_noeval = 1;
if (set_noeval)
noeval--;
if (curtok != COL)
- evalerror ("`:' expected for conditional expression");
+ evalerror (_("`:' expected for conditional expression"));
readtok ();
if (curtok == 0)
- evalerror ("expression expected");
+ evalerror (_("expression expected"));
set_noeval = 0;
if (cval)
{
set_noeval = 1;
noeval++;
}
- val2 = explor ();
+
+ val2 = expcond ();
if (set_noeval)
noeval--;
rval = cval ? val1 : val2;
}
/* 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 ();
}
/* Bitwise XOR. */
-static long
+static intmax_t
expbxor ()
{
- register long val1, val2;
+ register intmax_t val1, val2;
val1 = expband ();
}
/* Bitwise AND. */
-static long
+static intmax_t
expband ()
{
- register long val1, val2;
+ register intmax_t val1, val2;
val1 = exp5 ();
return (val1);
}
-static long
+static intmax_t
exp5 ()
{
- register long val1, val2;
+ register intmax_t val1, val2;
val1 = exp4 ();
return (val1);
}
-static long
+static intmax_t
exp4 ()
{
- register long val1, val2;
+ register intmax_t val1, val2;
val1 = expshift ();
while ((curtok == LEQ) ||
}
/* Left and right shifts. */
-static long
+static intmax_t
expshift ()
{
- register long val1, val2;
+ register intmax_t val1, val2;
val1 = exp3 ();
return (val1);
}
-static long
+static intmax_t
exp3 ()
{
- register long val1, val2;
+ register intmax_t val1, val2;
val1 = exp2 ();
return (val1);
}
-static long
+static intmax_t
exp2 ()
{
- register long val1, val2;
+ register intmax_t val1, val2;
val1 = exppower ();
val2 = exppower ();
if (((op == DIV) || (op == MOD)) && (val2 == 0))
- evalerror ("division by 0");
+ evalerror (_("division by 0"));
if (op == MUL)
val1 *= val2;
return (val1);
}
-static long
+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 */
if (val2 == 0)
return (1);
if (val2 < 0)
- evalerror ("exponent less than 0");
+ evalerror (_("exponent less than 0"));
for (c = 1; val2--; c *= val1)
;
val1 = c;
return (val1);
}
-static long
+static intmax_t
exp1 ()
{
- register long val;
+ register intmax_t val;
if (curtok == NOT)
{
return (val);
}
-static long
+static intmax_t
exp0 ()
{
- register long val = 0, v2;
+ 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. */
readtok ();
if (curtok != STR)
/* readtok() catches this */
- evalerror ("identifier expected after pre-increment or pre-decrement");
+ evalerror (_("identifier expected after pre-increment or pre-decrement"));
v2 = tokval + ((stok == PREINC) ? 1 : -1);
vincdec = itos (v2);
if (noeval == 0)
- (void)bind_int_variable (tokstr, vincdec);
+ expr_bind_variable (tokstr, vincdec);
free (vincdec);
val = v2;
readtok ();
val = EXP_HIGHEST ();
- 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 && (*tp == '+' || *tp == '-') && tp[1] == *tp &&
- (tp[2] == '\0' || (ISALNUM ((unsigned char)tp[2]) == 0)))
+ if (curtok == STR)
{
+ SAVETOK (&ec);
+ tokstr = (char *)NULL; /* keep it from being freed */
+ noeval = 1;
+ readtok ();
+ stok = curtok;
+
/* post-increment or post-decrement */
- v2 = val + ((*tp == '+') ? 1 : -1);
- vincdec = itos (v2);
- if (noeval == 0)
- (void)bind_int_variable (tokstr, vincdec);
- free (vincdec);
- tp += 2;
- curtok = NUM; /* make sure x++=7 is flagged as an error */
+ if (stok == POSTINC || stok == POSTDEC)
+ {
+ /* restore certain portions of EC */
+ tokstr = ec.tokstr;
+ noeval = ec.noeval;
+ lasttok = STR; /* ec.curtok */
+
+ v2 = val + ((stok == POSTINC) ? 1 : -1);
+ vincdec = itos (v2);
+ if (noeval == 0)
+ expr_bind_variable (tokstr, vincdec);
+ free (vincdec);
+ curtok = NUM; /* make sure x++=7 is flagged as an error */
+ }
+ else
+ {
+ 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 intmax_t
+expr_streval (tok, e)
+ char *tok;
+ int e;
+{
+ SHELL_VAR *v;
+ char *value;
+ intmax_t tval;
+
+ /* [[[[[ */
+#if defined (ARRAY_VARS)
+ v = (e == ']') ? array_variable_part (tok, (char **)0, (int *)0) : find_variable (tok);
+#else
+ v = find_variable (tok);
+#endif
+
+ if ((v == 0 || invisible_p (v)) && unbound_vars_is_error)
+ {
+#if defined (ARRAY_VARS)
+ value = (e == ']') ? array_variable_name (tok, (char **)0, (int *)0) : tok;
+#else
+ value = tok;
+#endif
+
+ err_unboundvar (value);
+
+#if defined (ARRAY_VARS)
+ if (e == ']')
+ FREE (value); /* array_variable_name returns new memory */
+#endif
+
+ if (interactive_shell)
+ {
+ expr_unwind ();
+ top_level_cleanup ();
+ jump_to_top_level (DISCARD);
+ }
+ else
+ jump_to_top_level (FORCE_EOF);
+ }
+
+#if defined (ARRAY_VARS)
+ /* Second argument of 0 to get_array_value means that 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. */
+ value = (e == ']') ? get_array_value (tok, 0, (int *)NULL) : get_variable_value (v);
+#else
+ value = get_variable_value (v);
+#endif
+
+ tval = (value && *value) ? subexpr (value) : 0;
+
+ 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 char *cp, *xp;
register unsigned char c, c1;
register int e;
if (c)
cp++;
- lasttp = tp = cp - 1;
-
if (c == '\0')
{
lasttok = curtok;
tp = cp;
return;
}
+ lasttp = tp = cp - 1;
if (legal_variable_starter (c))
{
/* variable names not preceded with a dollar sign are shell variables. */
- char *value, *savecp;
+ char *savecp;
EXPR_CONTEXT ec;
int peektok;
e = ']';
}
else
- evalerror ("bad array subscript");
+ evalerror (bash_badsub_errmsg);
}
#endif /* ARRAY_VARS */
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 */
/* 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)
- {
-#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
- }
+ tokval = expr_streval (tokstr, e);
else
tokval = 0;
c = LOR;
else if ((c == '*') && (c1 == '*'))
c = POWER;
- else if ((c == '-') && (c1 == '-') && legal_variable_starter ((unsigned char)*cp))
- c = PREDEC;
- else if ((c == '+') && (c1 == '+') && legal_variable_starter ((unsigned char)*cp))
- c = PREINC;
+ else if ((c == '-' || c == '+') && c1 == c && curtok == STR)
+ c = (c == '-') ? POSTDEC : POSTINC;
+ 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
+ cp--; /* not preinc or predec, so unget the character */
+ }
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++)
;
- internal_error ("%s%s%s: %s (error token is \"%s\")",
+ internal_error (_("%s%s%s: %s (error token is \"%s\")"),
name ? name : "", name ? ": " : "", t,
msg, (lasttp && *lasttp) ? lasttp : "");
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 --
+ from [0-9][a-z][A-Z]_@ (a = 10, z = 35, A = 36, Z = 61, @ = 62, _ = 63 --
you get the picture). */
-static long
+static intmax_t
strlong (num)
char *num;
{
register char *s;
register unsigned char c;
int base, foundbase;
- long val;
+ intmax_t val;
s = num;
if (c == '#')
{
if (foundbase)
- evalerror ("bad number");
+ evalerror (_("invalid number"));
/* Illegal base specifications raise an evaluation error. */
if (val < 2 || val > 64)
- evalerror ("illegal arithmetic base");
+ evalerror (_("invalid arithmetic base"));
base = val;
val = 0;
c = 63;
if (c >= base)
- evalerror ("value too great for base");
+ evalerror (_("value too great for base"));
val = (val * base) + c;
}
else
break;
}
+
return (val);
}
char **argv;
{
register int i;
- long v;
+ intmax_t v;
int expok;
if (setjmp (top_level))
{
v = evalexp (argv[i], &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);
}
char *
itos (n)
- long n;
+ intmax_t n;
{
return ("42");
}
projects / platform / upstream / bash.git / blobdiff