/* 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 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]
+ "++id", "--id" [pre-increment and pre-decrement]
"-", "+" [(unary operators)]
"!", "~"
+ "**" [(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
chet@ins.CWRU.Edu
*/
+#include "config.h"
+
#include <stdio.h>
#include "bashansi.h"
-#include "shell.h"
-#define variable_starter(c) (isletter(c) || (c == '_'))
-#define variable_character(c) (isletter(c) || (c == '_') || digit(c))
+#if defined (HAVE_UNISTD_H)
+# ifdef _MINIX
+# include <sys/types.h>
+# endif
+# include <unistd.h>
+#endif
+
+#include "chartypes.h"
+#include "bashintl.h"
+
+#include "shell.h"
/* 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'))
-extern char *this_command_name;
-
-static char *expression = (char *) NULL; /* The current expression */
-static char *tp = (char *) NULL; /* token lexical position */
-static char *lasttp;
-static int curtok = 0; /* the current token */
-static int lasttok = 0; /* the previous token */
-static int assigntok = 0; /* the OP in OP= */
-static char *tokstr = (char *) NULL; /* current token string */
-static int tokval = 0; /* current token value */
-static jmp_buf evalbuf;
-
-static void readtok (); /* lexical analyzer */
-static long expassign (), exp0 (), exp1 (), exp2 (), exp3 (),
- exp4 (), exp5 (), expshift (), expland (), explor (),
- expband (), expbor (), expbxor ();
-static long strlong ();
-static void evalerror ();
-
-/* A structure defining a single expression context. */
-typedef struct {
- int curtok, lasttok;
- char *expression, *tp;
- int tokval;
- char *tokstr;
-} EXPR_CONTEXT;
-
-/* Global var which contains the stack of expression contexts. */
-static EXPR_CONTEXT **expr_stack;
-static int expr_depth = 0; /* Location in the stack. */
-static int expr_stack_size = 0; /* Number of slots already allocated. */
-
/* Size be which the expression stack grows when neccessary. */
#define EXPR_STACK_GROW_SIZE 10
/* Maximum amount of recursion allowed. This prevents a non-integer
variable such as "num=num+2" from infinitely adding to itself when
- "let num=num+2" is given. I have to talk to Chet about this hack. */
+ "let num=num+2" is given. */
#define MAX_EXPR_RECURSION_LEVEL 1024
/* The Tokens. Singing "The Lion Sleeps Tonight". */
#define LSH 9 /* "<<" Left SHift */
#define RSH 10 /* ">>" Right SHift */
#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 LPAR '('
#define RPAR ')'
#define BAND '&' /* Bitwise AND */
-#define BOR '|' /* Either Bitwise OR, or what Chet is. */
+#define BOR '|' /* Bitwise OR. */
#define BXOR '^' /* Bitwise eXclusive OR. */
#define BNOT '~' /* Bitwise NOT; Two's complement. */
+#define QUES '?'
+#define COL ':'
+#define COMMA ','
+
+/* This should be the function corresponding to the operator with the
+ highest precedence. */
+#define EXP_HIGHEST expcomma
+
+static char *expression; /* The current expression */
+static char *tp; /* token lexical position */
+static char *lasttp; /* pointer to last token position */
+static int curtok; /* the current token */
+static int lasttok; /* the previous token */
+static int assigntok; /* the OP in OP= */
+static char *tokstr; /* current token string */
+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 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 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;
+ intmax_t tokval;
+ char *tokstr;
+ int noeval;
+} EXPR_CONTEXT;
+
+#ifdef INCLUDE_UNUSED
+/* Not used yet. */
+typedef struct {
+ char *tokstr;
+ intmax_t tokval;
+} LVALUE;
+#endif
+
+/* 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;
+extern int unbound_vars_is_error;
+
+#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; \
+ } 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; \
+ } while (0)
/* Push and save away the contents of the globals describing the
current expression context. */
{
EXPR_CONTEXT *context;
- context = (EXPR_CONTEXT *)xmalloc (sizeof (EXPR_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->curtok = curtok;
- context->lasttok = lasttok;
+ context = (EXPR_CONTEXT *)xmalloc (sizeof (EXPR_CONTEXT));
+
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");
+ 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);
}
-/* Evaluate EXPR, and return the arithmetic result.
+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
+ value is returned in *VALIDP, the return value of evalexp() may
+ be used.
The `while' loop after the longjmp is caught relies on the above
implementation of pushexp and popexp leaving in expr_stack[0] the
values that the variables had when the program started. That is,
- the first things saved are the initial values of the variables that
+ the first things saved are the initial values of the variables that
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)
+intmax_t
+evalexp (expr, validp)
char *expr;
+ int *validp;
{
- long val = 0L;
- jmp_buf old_evalbuf;
- char *p;
+ intmax_t val;
+ int c;
+ procenv_t oevalbuf;
- for (p = expr; p && *p && cr_whitespace (*p); p++)
- ;
+ val = 0;
+ noeval = 0;
- if (p == NULL || *p == '\0')
- return (0);
+ FASTCOPY (evalbuf, oevalbuf, sizeof (evalbuf));
- /* Save the value of evalbuf to protect it around possible recursive
- calls to evalexp (). */
- xbcopy ((char *)evalbuf, (char *)old_evalbuf, sizeof (jmp_buf));
+ c = setjmp (evalbuf);
- if (setjmp (evalbuf))
+ if (c)
{
- if (tokstr) /* Clean up local allocation. */
- free (tokstr);
+ FREE (tokstr);
+ FREE (expression);
+ tokstr = expression = (char *)NULL;
- if (expression)
- free (expression);
+ expr_unwind ();
- while (--expr_depth)
- {
- if (expr_stack[expr_depth]->tokstr)
- free (expr_stack[expr_depth]->tokstr);
-
- if (expr_stack[expr_depth]->expression)
- free (expr_stack[expr_depth]->expression);
- }
- longjmp (top_level, DISCARD);
+ if (validp)
+ *validp = 0;
+ return (0);
}
+ val = subexpr (expr);
+
+ if (validp)
+ *validp = 1;
+
+ FASTCOPY (oevalbuf, evalbuf, sizeof (evalbuf));
+
+ return (val);
+}
+
+static intmax_t
+subexpr (expr)
+ char *expr;
+{
+ intmax_t val;
+ char *p;
+
+ for (p = expr; p && *p && cr_whitespace (*p); p++)
+ ;
+
+ if (p == NULL || *p == '\0')
+ return (0);
+
pushexp ();
curtok = lasttok = 0;
expression = savestring (expr);
tp = expression;
tokstr = (char *)NULL;
- tokval = 0l;
+ tokval = 0;
readtok ();
- val = expassign ();
+ val = EXP_HIGHEST ();
- if (curtok != 0)
- evalerror ("syntax error in expression");
+ if (curtok != 0)
+ evalerror (_("syntax error in expression"));
- if (tokstr)
- free (tokstr);
- if (expression)
- free (expression);
+ FREE (tokstr);
+ FREE (expression);
popexp ();
- /* Restore the value of evalbuf so that any subsequent longjmp calls
- will have a valid location to jump to. */
- xbcopy ((char *)old_evalbuf, (char *)evalbuf, sizeof (jmp_buf));
-
- return (val);
+ 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;
- value = explor ();
+ value = expcond ();
if (curtok == EQ || curtok == OP_ASSIGN)
{
- int special = curtok == OP_ASSIGN;
- int op;
- long lvalue;
+ int special, op;
+ intmax_t lvalue;
+
+ special = curtok == OP_ASSIGN;
if (lasttok != STR)
- evalerror ("attempted expassign 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:
case BOR:
lvalue |= value;
break;
+ case BXOR:
+ lvalue ^= value;
+ break;
default:
- evalerror ("bug: bad expassign token %d", assigntok);
+ free (lhs);
+ evalerror (_("bug: bad expassign token"));
break;
}
value = lvalue;
}
rhs = itos (value);
- bind_int_variable (lhs, rhs);
+ if (noeval == 0)
+ expr_bind_variable (lhs, rhs);
free (rhs);
free (lhs);
- free (tokstr);
+ FREE (tokstr);
tokstr = (char *)NULL; /* For freeing on errors. */
}
return (value);
}
+/* Conditional expression (expr?expr:expr) */
+static intmax_t
+expcond ()
+{
+ 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++;
+ }
+
+ val1 = EXP_HIGHEST ();
+
+ if (set_noeval)
+ noeval--;
+ if (curtok != COL)
+ evalerror (_("`:' expected for conditional expression"));
+ readtok ();
+ if (curtok == 0)
+ evalerror (_("expression expected"));
+ set_noeval = 0;
+ if (cval)
+ {
+ set_noeval = 1;
+ noeval++;
+ }
+
+ val2 = expcond ();
+ if (set_noeval)
+ noeval--;
+ rval = cval ? val1 : val2;
+ lasttok = COND;
+ }
+ return rval;
+}
+
/* Logical OR. */
-static long
+static intmax_t
explor ()
{
- register long val1, val2;
+ register intmax_t val1, val2;
+ int set_noeval;
val1 = expland ();
while (curtok == LOR)
{
+ set_noeval = 0;
+ if (val1 != 0)
+ {
+ noeval++;
+ set_noeval = 1;
+ }
readtok ();
val2 = expland ();
+ if (set_noeval)
+ noeval--;
val1 = val1 || val2;
+ lasttok = LOR;
}
return (val1);
}
/* Logical AND. */
-static long
+static intmax_t
expland ()
{
- register long val1, val2;
+ register intmax_t val1, val2;
+ int set_noeval;
val1 = expbor ();
while (curtok == LAND)
{
+ set_noeval = 0;
+ if (val1 == 0)
+ {
+ set_noeval = 1;
+ noeval++;
+ }
readtok ();
val2 = expbor ();
+ if (set_noeval)
+ noeval--;
val1 = val1 && val2;
+ lasttok = LAND;
}
return (val1);
}
/* 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) ||
val1 = val1 >= val2;
else if (op == LT)
val1 = val1 < val2;
- else if (op == GT)
+ else /* (op == GT) */
val1 = val1 > val2;
}
return (val1);
}
/* 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 = exp1 ();
+ val1 = exppower ();
while ((curtok == MUL) ||
- (curtok == DIV) ||
- (curtok == MOD))
+ (curtok == DIV) ||
+ (curtok == MOD))
{
int op = curtok;
readtok ();
- val2 = exp1 ();
+ val2 = exppower ();
if (((op == DIV) || (op == MOD)) && (val2 == 0))
- evalerror ("division by 0");
+ evalerror (_("division by 0"));
if (op == MUL)
- val1 *= val2;
+ val1 *= val2;
else if (op == DIV)
- val1 /= val2;
+ val1 /= val2;
else if (op == MOD)
- val1 %= val2;
+ val1 %= val2;
}
return (val1);
}
-static long
+static intmax_t
+exppower ()
+{
+ register intmax_t val1, val2, c;
+
+ val1 = exp1 ();
+ while (curtok == POWER)
+ {
+ readtok ();
+ val2 = exppower (); /* exponentiation is right-associative */
+ if (val2 == 0)
+ return (1);
+ if (val2 < 0)
+ evalerror (_("exponent less than 0"));
+ for (c = 1; val2--; c *= val1)
+ ;
+ val1 = c;
+ }
+ return (val1);
+}
+
+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 = 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 ();
+ 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)
+ expr_bind_variable (tokstr, vincdec);
+ free (vincdec);
+ val = v2;
+
+ curtok = NUM; /* make sure --x=7 is flagged as an error */
+ readtok ();
+ }
+ else if (curtok == MINUS)
{
readtok ();
val = - exp0 ();
else if (curtok == LPAR)
{
readtok ();
- val = expassign ();
+ 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)
+ {
+ 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;
+ 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 in expression");
+ 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 = tp;
- register int c, c1;
+ register char *cp, *xp;
+ register unsigned char c, c1;
+ register int e;
/* Skip leading whitespace. */
- c = 0;
+ cp = tp;
+ c = e = 0;
while (cp && (c = *cp) && (cr_whitespace (c)))
cp++;
if (c)
cp++;
-
- lasttp = tp = cp - 1;
if (c == '\0')
{
tp = cp;
return;
}
+ lasttp = tp = cp - 1;
- if (variable_starter (c))
+ if (legal_variable_starter (c))
{
- /* Semi-bogus K*rn shell 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 (variable_character (c))
+ while (legal_variable_char (c))
c = *cp++;
c = *--cp;
- *cp = '\0';
- if (tokstr)
- free (tokstr);
+#if defined (ARRAY_VARS)
+ if (c == '[')
+ {
+ e = skipsubscript (cp, 0);
+ if (cp[e] == ']')
+ {
+ cp += e + 1;
+ c = *cp;
+ e = ']';
+ }
+ else
+ evalerror (bash_badsub_errmsg);
+ }
+#endif /* ARRAY_VARS */
+
+ *cp = '\0';
+ FREE (tokstr);
tokstr = savestring (tp);
- value = get_string_value (tokstr);
+ *cp = c;
- if (value && *value)
- tokval = evalexp (value);
+ 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)
+ tokval = expr_streval (tokstr, e);
else
tokval = 0;
- *cp = c;
lasttok = curtok;
curtok = STR;
}
- else if (digit(c))
+ else if (DIGIT(c))
{
- while (digit (c) || isletter (c) || c == '#')
+ while (ISALNUM (c) || c == '#' || c == '@' || c == '_')
c = *cp++;
c = *--cp;
else
{
c1 = *cp++;
- if ((c == EQ) && (c1 == EQ))
+ if ((c == EQ) && (c1 == EQ))
c = EQEQ;
else if ((c == NOT) && (c1 == EQ))
c = NEQ;
c = LAND;
else if ((c == BOR) && (c1 == BOR))
c = LOR;
- else if (c1 == EQ && member(c, "*/%+-&^|"))
+ else if ((c == '*') && (c1 == '*'))
+ c = POWER;
+ 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;
- if (name == 0)
- name = get_name_for_error ();
for (t = expression; whitespace (*t); t++)
;
- fprintf (stderr, "%s: %s: %s (remainder of expression is \"%s\")\n",
- name, t,
- msg, (lasttp && *lasttp) ? lasttp : "");
+ 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
- 0xnn -> base 16
- Anything else: [base#]number (this is from the ISO Pascal spec). */
-static long
+ 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 --
+ you get the picture). */
+
+static intmax_t
strlong (num)
char *num;
{
- register char *s = num;
- register int c;
- int base = 10;
- long val = 0L;
+ register char *s;
+ register unsigned char c;
+ int base, foundbase;
+ intmax_t val;
- if (s == NULL || *s == '\0')
- return 0L;
+ s = num;
+ base = 10;
+ foundbase = 0;
if (*s == '0')
{
s++;
- if (s == NULL || *s == '\0')
- return 0L;
-
+ if (*s == '\0')
+ return 0;
+
/* Base 16? */
if (*s == 'x' || *s == 'X')
{
}
else
base = 8;
+ foundbase++;
}
+ val = 0;
for (c = *s++; c; c = *s++)
{
if (c == '#')
{
- base = (int)val;
+ if (foundbase)
+ evalerror (_("invalid number"));
- /* Illegal base specifications are silently reset to base 10.
- I don't think that this is a good idea? */
- if (base < 2 || base > 36)
- base = 10;
+ /* Illegal base specifications raise an evaluation error. */
+ if (val < 2 || val > 64)
+ evalerror (_("invalid arithmetic base"));
- val = 0L;
+ base = val;
+ val = 0;
+ foundbase++;
+ }
+ else if (ISALNUM(c) || (c == '_') || (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 = 63;
+
+ if (c >= base)
+ evalerror (_("value too great for base"));
+
+ val = (val * base) + c;
}
else
- if (isletter(c) || digit(c))
- {
- if (digit(c))
- c = digit_value(c);
- else if (c >= 'a' && c <= 'z')
- c -= 'a' - 10;
- else if (c >= 'A' && c <= 'Z')
- c -= 'A' - 10;
-
- if (c >= base)
- evalerror ("value too great for base");
-
- val = (val * base) + c;
- }
- else
- break;
+ 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 *get_string_value () { return 0; }
-jmp_buf top_level;
+procenv_t top_level;
main (argc, argv)
int argc;
char **argv;
{
register int i;
- long v;
+ intmax_t v;
+ int expok;
if (setjmp (top_level))
exit (0);
for (i = 1; i < argc; i++)
{
- v = evalexp (argv[i]);
- printf ("'%s' -> %ld\n", argv[i], v);
+ v = evalexp (argv[i], &expok);
+ if (expok == 0)
+ fprintf (stderr, _("%s: expression error\n"), argv[i]);
+ else
+ printf ("'%s' -> %ld\n", argv[i], v);
}
exit (0);
}
char *
itos (n)
- int n;
+ intmax_t n;
{
return ("42");
}