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726f6388 JA |
1 | /* expr.c -- arithmetic expression evaluation. */ |
2 | ||
ac50fbac | 3 | /* Copyright (C) 1990-2013 Free Software Foundation, Inc. |
726f6388 JA |
4 | |
5 | This file is part of GNU Bash, the Bourne Again SHell. | |
6 | ||
3185942a JA |
7 | Bash is free software: you can redistribute it and/or modify |
8 | it under the terms of the GNU General Public License as published by | |
9 | the Free Software Foundation, either version 3 of the License, or | |
10 | (at your option) any later version. | |
726f6388 | 11 | |
3185942a JA |
12 | Bash is distributed in the hope that it will be useful, |
13 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
15 | GNU General Public License for more details. | |
726f6388 JA |
16 | |
17 | You should have received a copy of the GNU General Public License | |
3185942a JA |
18 | along with Bash. If not, see <http://www.gnu.org/licenses/>. |
19 | */ | |
726f6388 JA |
20 | |
21 | /* | |
7117c2d2 | 22 | All arithmetic is done as intmax_t integers with no checking for overflow |
726f6388 JA |
23 | (though division by 0 is caught and flagged as an error). |
24 | ||
25 | The following operators are handled, grouped into a set of levels in | |
26 | order of decreasing precedence. | |
27 | ||
bb70624e JA |
28 | "id++", "id--" [post-increment and post-decrement] |
29 | "++id", "--id" [pre-increment and pre-decrement] | |
726f6388 JA |
30 | "-", "+" [(unary operators)] |
31 | "!", "~" | |
cce855bc | 32 | "**" [(exponentiation)] |
726f6388 JA |
33 | "*", "/", "%" |
34 | "+", "-" | |
35 | "<<", ">>" | |
36 | "<=", ">=", "<", ">" | |
37 | "==", "!=" | |
38 | "&" | |
39 | "^" | |
40 | "|" | |
41 | "&&" | |
42 | "||" | |
ccc6cda3 | 43 | "expr ? expr : expr" |
cce855bc | 44 | "=", "*=", "/=", "%=", "+=", "-=", "<<=", ">>=", "&=", "^=", "|=" |
b80f6443 | 45 | , [comma] |
726f6388 JA |
46 | |
47 | (Note that most of these operators have special meaning to bash, and an | |
48 | entire expression should be quoted, e.g. "a=$a+1" or "a=a+1" to ensure | |
49 | that it is passed intact to the evaluator when using `let'. When using | |
50 | the $[] or $(( )) forms, the text between the `[' and `]' or `((' and `))' | |
51 | is treated as if in double quotes.) | |
52 | ||
53 | Sub-expressions within parentheses have a precedence level greater than | |
54 | all of the above levels and are evaluated first. Within a single prece- | |
55 | dence group, evaluation is left-to-right, except for the arithmetic | |
56 | assignment operator (`='), which is evaluated right-to-left (as in C). | |
57 | ||
58 | The expression evaluator returns the value of the expression (assignment | |
59 | statements have as a value what is returned by the RHS). The `let' | |
60 | builtin, on the other hand, returns 0 if the last expression evaluates to | |
61 | a non-zero, and 1 otherwise. | |
62 | ||
63 | Implementation is a recursive-descent parser. | |
64 | ||
65 | Chet Ramey | |
ac50fbac | 66 | chet@po.cwru.edu |
726f6388 JA |
67 | */ |
68 | ||
ccc6cda3 JA |
69 | #include "config.h" |
70 | ||
726f6388 JA |
71 | #include <stdio.h> |
72 | #include "bashansi.h" | |
cce855bc | 73 | |
ccc6cda3 | 74 | #if defined (HAVE_UNISTD_H) |
cce855bc JA |
75 | # ifdef _MINIX |
76 | # include <sys/types.h> | |
77 | # endif | |
ccc6cda3 JA |
78 | # include <unistd.h> |
79 | #endif | |
726f6388 | 80 | |
f73dda09 | 81 | #include "chartypes.h" |
b80f6443 | 82 | #include "bashintl.h" |
bb70624e | 83 | |
ccc6cda3 | 84 | #include "shell.h" |
ac50fbac | 85 | #include "typemax.h" /* INTMAX_MAX, INTMAX_MIN */ |
726f6388 JA |
86 | |
87 | /* Because of the $((...)) construct, expressions may include newlines. | |
88 | Here is a macro which accepts newlines, tabs and spaces as whitespace. */ | |
89 | #define cr_whitespace(c) (whitespace(c) || ((c) == '\n')) | |
90 | ||
ac50fbac | 91 | /* Size be which the expression stack grows when necessary. */ |
726f6388 JA |
92 | #define EXPR_STACK_GROW_SIZE 10 |
93 | ||
94 | /* Maximum amount of recursion allowed. This prevents a non-integer | |
95 | variable such as "num=num+2" from infinitely adding to itself when | |
ccc6cda3 | 96 | "let num=num+2" is given. */ |
726f6388 JA |
97 | #define MAX_EXPR_RECURSION_LEVEL 1024 |
98 | ||
99 | /* The Tokens. Singing "The Lion Sleeps Tonight". */ | |
100 | ||
101 | #define EQEQ 1 /* "==" */ | |
102 | #define NEQ 2 /* "!=" */ | |
103 | #define LEQ 3 /* "<=" */ | |
104 | #define GEQ 4 /* ">=" */ | |
105 | #define STR 5 /* string */ | |
106 | #define NUM 6 /* number */ | |
107 | #define LAND 7 /* "&&" Logical AND */ | |
108 | #define LOR 8 /* "||" Logical OR */ | |
109 | #define LSH 9 /* "<<" Left SHift */ | |
110 | #define RSH 10 /* ">>" Right SHift */ | |
111 | #define OP_ASSIGN 11 /* op= expassign as in Posix.2 */ | |
cce855bc JA |
112 | #define COND 12 /* exp1 ? exp2 : exp3 */ |
113 | #define POWER 13 /* exp1**exp2 */ | |
bb70624e JA |
114 | #define PREINC 14 /* ++var */ |
115 | #define PREDEC 15 /* --var */ | |
116 | #define POSTINC 16 /* var++ */ | |
117 | #define POSTDEC 17 /* var-- */ | |
726f6388 JA |
118 | #define EQ '=' |
119 | #define GT '>' | |
120 | #define LT '<' | |
121 | #define PLUS '+' | |
122 | #define MINUS '-' | |
123 | #define MUL '*' | |
124 | #define DIV '/' | |
125 | #define MOD '%' | |
126 | #define NOT '!' | |
127 | #define LPAR '(' | |
128 | #define RPAR ')' | |
129 | #define BAND '&' /* Bitwise AND */ | |
ccc6cda3 | 130 | #define BOR '|' /* Bitwise OR. */ |
726f6388 JA |
131 | #define BXOR '^' /* Bitwise eXclusive OR. */ |
132 | #define BNOT '~' /* Bitwise NOT; Two's complement. */ | |
ccc6cda3 JA |
133 | #define QUES '?' |
134 | #define COL ':' | |
bb70624e JA |
135 | #define COMMA ',' |
136 | ||
137 | /* This should be the function corresponding to the operator with the | |
138 | highest precedence. */ | |
139 | #define EXP_HIGHEST expcomma | |
ccc6cda3 | 140 | |
495aee44 CR |
141 | #ifndef MAX_INT_LEN |
142 | # define MAX_INT_LEN 32 | |
143 | #endif | |
144 | ||
145 | struct lvalue | |
146 | { | |
147 | char *tokstr; /* possibly-rewritten lvalue if not NULL */ | |
148 | intmax_t tokval; /* expression evaluated value */ | |
149 | SHELL_VAR *tokvar; /* variable described by array or var reference */ | |
150 | intmax_t ind; /* array index if not -1 */ | |
151 | }; | |
152 | ||
153 | /* A structure defining a single expression context. */ | |
154 | typedef struct { | |
155 | int curtok, lasttok; | |
156 | char *expression, *tp, *lasttp; | |
157 | intmax_t tokval; | |
158 | char *tokstr; | |
159 | int noeval; | |
160 | struct lvalue lval; | |
161 | } EXPR_CONTEXT; | |
162 | ||
ccc6cda3 JA |
163 | static char *expression; /* The current expression */ |
164 | static char *tp; /* token lexical position */ | |
165 | static char *lasttp; /* pointer to last token position */ | |
166 | static int curtok; /* the current token */ | |
167 | static int lasttok; /* the previous token */ | |
168 | static int assigntok; /* the OP in OP= */ | |
169 | static char *tokstr; /* current token string */ | |
7117c2d2 | 170 | static intmax_t tokval; /* current token value */ |
ccc6cda3 JA |
171 | static int noeval; /* set to 1 if no assignment to be done */ |
172 | static procenv_t evalbuf; | |
173 | ||
495aee44 CR |
174 | static struct lvalue curlval = {0, 0, 0, -1}; |
175 | static struct lvalue lastlval = {0, 0, 0, -1}; | |
176 | ||
0628567a | 177 | static int _is_arithop __P((int)); |
f73dda09 | 178 | static void readtok __P((void)); /* lexical analyzer */ |
7117c2d2 | 179 | |
495aee44 CR |
180 | static void init_lvalue __P((struct lvalue *)); |
181 | static struct lvalue *alloc_lvalue __P((void)); | |
182 | static void free_lvalue __P((struct lvalue *)); | |
183 | ||
184 | static intmax_t expr_streval __P((char *, int, struct lvalue *)); | |
7117c2d2 | 185 | static intmax_t strlong __P((char *)); |
3185942a | 186 | static void evalerror __P((const char *)); |
f73dda09 JA |
187 | |
188 | static void pushexp __P((void)); | |
189 | static void popexp __P((void)); | |
7117c2d2 | 190 | static void expr_unwind __P((void)); |
b80f6443 | 191 | static void expr_bind_variable __P((char *, char *)); |
ac50fbac | 192 | #if defined (ARRAY_VARS) |
495aee44 | 193 | static void expr_bind_array_element __P((char *, arrayind_t, char *)); |
ac50fbac | 194 | #endif |
7117c2d2 JA |
195 | |
196 | static intmax_t subexpr __P((char *)); | |
197 | ||
198 | static intmax_t expcomma __P((void)); | |
199 | static intmax_t expassign __P((void)); | |
200 | static intmax_t expcond __P((void)); | |
201 | static intmax_t explor __P((void)); | |
202 | static intmax_t expland __P((void)); | |
203 | static intmax_t expbor __P((void)); | |
204 | static intmax_t expbxor __P((void)); | |
205 | static intmax_t expband __P((void)); | |
206 | static intmax_t exp5 __P((void)); | |
207 | static intmax_t exp4 __P((void)); | |
208 | static intmax_t expshift __P((void)); | |
209 | static intmax_t exp3 __P((void)); | |
210 | static intmax_t exp2 __P((void)); | |
211 | static intmax_t exppower __P((void)); | |
212 | static intmax_t exp1 __P((void)); | |
213 | static intmax_t exp0 __P((void)); | |
ccc6cda3 | 214 | |
ccc6cda3 JA |
215 | /* Global var which contains the stack of expression contexts. */ |
216 | static EXPR_CONTEXT **expr_stack; | |
217 | static int expr_depth; /* Location in the stack. */ | |
218 | static int expr_stack_size; /* Number of slots already allocated. */ | |
219 | ||
220 | extern char *this_command_name; | |
0001803f | 221 | extern int unbound_vars_is_error, last_command_exit_value; |
726f6388 | 222 | |
b80f6443 | 223 | #if defined (ARRAY_VARS) |
3185942a | 224 | extern const char * const bash_badsub_errmsg; |
b80f6443 JA |
225 | #endif |
226 | ||
bb70624e JA |
227 | #define SAVETOK(X) \ |
228 | do { \ | |
229 | (X)->curtok = curtok; \ | |
230 | (X)->lasttok = lasttok; \ | |
231 | (X)->tp = tp; \ | |
232 | (X)->lasttp = lasttp; \ | |
233 | (X)->tokval = tokval; \ | |
234 | (X)->tokstr = tokstr; \ | |
235 | (X)->noeval = noeval; \ | |
495aee44 | 236 | (X)->lval = curlval; \ |
bb70624e JA |
237 | } while (0) |
238 | ||
239 | #define RESTORETOK(X) \ | |
240 | do { \ | |
241 | curtok = (X)->curtok; \ | |
242 | lasttok = (X)->lasttok; \ | |
243 | tp = (X)->tp; \ | |
244 | lasttp = (X)->lasttp; \ | |
245 | tokval = (X)->tokval; \ | |
246 | tokstr = (X)->tokstr; \ | |
247 | noeval = (X)->noeval; \ | |
495aee44 | 248 | curlval = (X)->lval; \ |
bb70624e JA |
249 | } while (0) |
250 | ||
726f6388 JA |
251 | /* Push and save away the contents of the globals describing the |
252 | current expression context. */ | |
253 | static void | |
254 | pushexp () | |
255 | { | |
256 | EXPR_CONTEXT *context; | |
257 | ||
726f6388 | 258 | if (expr_depth >= MAX_EXPR_RECURSION_LEVEL) |
b80f6443 | 259 | evalerror (_("expression recursion level exceeded")); |
726f6388 JA |
260 | |
261 | if (expr_depth >= expr_stack_size) | |
262 | { | |
f73dda09 JA |
263 | expr_stack_size += EXPR_STACK_GROW_SIZE; |
264 | expr_stack = (EXPR_CONTEXT **)xrealloc (expr_stack, expr_stack_size * sizeof (EXPR_CONTEXT *)); | |
726f6388 JA |
265 | } |
266 | ||
d166f048 JA |
267 | context = (EXPR_CONTEXT *)xmalloc (sizeof (EXPR_CONTEXT)); |
268 | ||
726f6388 | 269 | context->expression = expression; |
bb70624e JA |
270 | SAVETOK(context); |
271 | ||
726f6388 JA |
272 | expr_stack[expr_depth++] = context; |
273 | } | |
274 | ||
275 | /* Pop the the contents of the expression context stack into the | |
276 | globals describing the current expression context. */ | |
277 | static void | |
278 | popexp () | |
279 | { | |
280 | EXPR_CONTEXT *context; | |
281 | ||
282 | if (expr_depth == 0) | |
b80f6443 | 283 | evalerror (_("recursion stack underflow")); |
726f6388 JA |
284 | |
285 | context = expr_stack[--expr_depth]; | |
bb70624e | 286 | |
726f6388 | 287 | expression = context->expression; |
bb70624e JA |
288 | RESTORETOK (context); |
289 | ||
726f6388 JA |
290 | free (context); |
291 | } | |
292 | ||
7117c2d2 JA |
293 | static void |
294 | expr_unwind () | |
295 | { | |
296 | while (--expr_depth > 0) | |
297 | { | |
298 | if (expr_stack[expr_depth]->tokstr) | |
299 | free (expr_stack[expr_depth]->tokstr); | |
300 | ||
301 | if (expr_stack[expr_depth]->expression) | |
302 | free (expr_stack[expr_depth]->expression); | |
303 | ||
304 | free (expr_stack[expr_depth]); | |
305 | } | |
306 | free (expr_stack[expr_depth]); /* free the allocated EXPR_CONTEXT */ | |
f1be666c JA |
307 | |
308 | noeval = 0; /* XXX */ | |
7117c2d2 JA |
309 | } |
310 | ||
b80f6443 JA |
311 | static void |
312 | expr_bind_variable (lhs, rhs) | |
313 | char *lhs, *rhs; | |
314 | { | |
ac50fbac CR |
315 | SHELL_VAR *v; |
316 | ||
317 | v = bind_int_variable (lhs, rhs); | |
318 | if (v && (readonly_p (v) || noassign_p (v))) | |
319 | longjmp (evalbuf, 1); /* variable assignment error */ | |
b80f6443 JA |
320 | stupidly_hack_special_variables (lhs); |
321 | } | |
322 | ||
ac50fbac | 323 | #if defined (ARRAY_VARS) |
495aee44 CR |
324 | /* Rewrite tok, which is of the form vname[expression], to vname[ind], where |
325 | IND is the already-calculated value of expression. */ | |
326 | static void | |
327 | expr_bind_array_element (tok, ind, rhs) | |
328 | char *tok; | |
329 | arrayind_t ind; | |
330 | char *rhs; | |
331 | { | |
332 | char *lhs, *vname; | |
333 | size_t llen; | |
334 | char ibuf[INT_STRLEN_BOUND (arrayind_t) + 1], *istr; | |
335 | ||
336 | istr = fmtumax (ind, 10, ibuf, sizeof (ibuf), 0); | |
337 | vname = array_variable_name (tok, (char **)NULL, (int *)NULL); | |
338 | ||
339 | llen = strlen (vname) + sizeof (ibuf) + 3; | |
340 | lhs = xmalloc (llen); | |
341 | ||
342 | sprintf (lhs, "%s[%s]", vname, istr); /* XXX */ | |
343 | ||
495aee44 | 344 | /*itrace("expr_bind_array_element: %s=%s", lhs, rhs);*/ |
ac50fbac | 345 | expr_bind_variable (lhs, rhs); |
495aee44 CR |
346 | free (vname); |
347 | free (lhs); | |
348 | } | |
ac50fbac | 349 | #endif /* ARRAY_VARS */ |
495aee44 | 350 | |
d166f048 JA |
351 | /* Evaluate EXPR, and return the arithmetic result. If VALIDP is |
352 | non-null, a zero is stored into the location to which it points | |
353 | if the expression is invalid, non-zero otherwise. If a non-zero | |
354 | value is returned in *VALIDP, the return value of evalexp() may | |
355 | be used. | |
726f6388 JA |
356 | |
357 | The `while' loop after the longjmp is caught relies on the above | |
358 | implementation of pushexp and popexp leaving in expr_stack[0] the | |
359 | values that the variables had when the program started. That is, | |
ccc6cda3 | 360 | the first things saved are the initial values of the variables that |
726f6388 JA |
361 | were assigned at program startup or by the compiler. Therefore, it is |
362 | safe to let the loop terminate when expr_depth == 0, without freeing up | |
363 | any of the expr_depth[0] stuff. */ | |
7117c2d2 | 364 | intmax_t |
d166f048 | 365 | evalexp (expr, validp) |
726f6388 | 366 | char *expr; |
d166f048 | 367 | int *validp; |
726f6388 | 368 | { |
7117c2d2 | 369 | intmax_t val; |
b80f6443 JA |
370 | int c; |
371 | procenv_t oevalbuf; | |
726f6388 | 372 | |
f73dda09 | 373 | val = 0; |
f1be666c | 374 | noeval = 0; |
726f6388 | 375 | |
b80f6443 JA |
376 | FASTCOPY (evalbuf, oevalbuf, sizeof (evalbuf)); |
377 | ||
ac50fbac | 378 | c = setjmp_nosigs (evalbuf); |
b80f6443 JA |
379 | |
380 | if (c) | |
726f6388 | 381 | { |
d166f048 JA |
382 | FREE (tokstr); |
383 | FREE (expression); | |
384 | tokstr = expression = (char *)NULL; | |
726f6388 | 385 | |
7117c2d2 | 386 | expr_unwind (); |
d166f048 JA |
387 | |
388 | if (validp) | |
389 | *validp = 0; | |
f73dda09 | 390 | return (0); |
726f6388 JA |
391 | } |
392 | ||
d166f048 JA |
393 | val = subexpr (expr); |
394 | ||
d166f048 JA |
395 | if (validp) |
396 | *validp = 1; | |
397 | ||
b80f6443 JA |
398 | FASTCOPY (oevalbuf, evalbuf, sizeof (evalbuf)); |
399 | ||
d166f048 JA |
400 | return (val); |
401 | } | |
402 | ||
7117c2d2 | 403 | static intmax_t |
d166f048 JA |
404 | subexpr (expr) |
405 | char *expr; | |
406 | { | |
7117c2d2 | 407 | intmax_t val; |
d166f048 JA |
408 | char *p; |
409 | ||
410 | for (p = expr; p && *p && cr_whitespace (*p); p++) | |
411 | ; | |
412 | ||
413 | if (p == NULL || *p == '\0') | |
f73dda09 | 414 | return (0); |
d166f048 | 415 | |
726f6388 | 416 | pushexp (); |
726f6388 JA |
417 | expression = savestring (expr); |
418 | tp = expression; | |
419 | ||
495aee44 | 420 | curtok = lasttok = 0; |
726f6388 | 421 | tokstr = (char *)NULL; |
f73dda09 | 422 | tokval = 0; |
495aee44 CR |
423 | init_lvalue (&curlval); |
424 | lastlval = curlval; | |
726f6388 JA |
425 | |
426 | readtok (); | |
427 | ||
bb70624e | 428 | val = EXP_HIGHEST (); |
726f6388 | 429 | |
ccc6cda3 | 430 | if (curtok != 0) |
b80f6443 | 431 | evalerror (_("syntax error in expression")); |
726f6388 | 432 | |
d166f048 JA |
433 | FREE (tokstr); |
434 | FREE (expression); | |
726f6388 JA |
435 | |
436 | popexp (); | |
437 | ||
d166f048 | 438 | return val; |
726f6388 JA |
439 | } |
440 | ||
7117c2d2 | 441 | static intmax_t |
bb70624e | 442 | expcomma () |
726f6388 | 443 | { |
7117c2d2 | 444 | register intmax_t value; |
726f6388 | 445 | |
bb70624e JA |
446 | value = expassign (); |
447 | while (curtok == COMMA) | |
726f6388 | 448 | { |
bb70624e JA |
449 | readtok (); |
450 | value = expassign (); | |
726f6388 JA |
451 | } |
452 | ||
bb70624e | 453 | return value; |
726f6388 | 454 | } |
bb70624e | 455 | |
7117c2d2 | 456 | static intmax_t |
726f6388 JA |
457 | expassign () |
458 | { | |
7117c2d2 | 459 | register intmax_t value; |
726f6388 | 460 | char *lhs, *rhs; |
495aee44 | 461 | arrayind_t lind; |
ac50fbac CR |
462 | #if defined (HAVE_IMAXDIV) |
463 | imaxdiv_t idiv; | |
464 | #endif | |
726f6388 | 465 | |
ccc6cda3 | 466 | value = expcond (); |
726f6388 JA |
467 | if (curtok == EQ || curtok == OP_ASSIGN) |
468 | { | |
ccc6cda3 | 469 | int special, op; |
7117c2d2 | 470 | intmax_t lvalue; |
726f6388 | 471 | |
ccc6cda3 JA |
472 | special = curtok == OP_ASSIGN; |
473 | ||
726f6388 | 474 | if (lasttok != STR) |
b80f6443 | 475 | evalerror (_("attempted assignment to non-variable")); |
726f6388 JA |
476 | |
477 | if (special) | |
478 | { | |
479 | op = assigntok; /* a OP= b */ | |
480 | lvalue = value; | |
481 | } | |
482 | ||
ac50fbac | 483 | /* XXX - watch out for pointer aliasing issues here */ |
726f6388 | 484 | lhs = savestring (tokstr); |
495aee44 CR |
485 | /* save ind in case rhs is string var and evaluation overwrites it */ |
486 | lind = curlval.ind; | |
726f6388 JA |
487 | readtok (); |
488 | value = expassign (); | |
489 | ||
490 | if (special) | |
491 | { | |
cf391c36 CR |
492 | if ((op == DIV || op == MOD) && value == 0) |
493 | { | |
494 | if (noeval == 0) | |
495 | evalerror (_("division by 0")); | |
496 | else | |
497 | value = 1; | |
498 | } | |
499 | ||
726f6388 JA |
500 | switch (op) |
501 | { | |
502 | case MUL: | |
503 | lvalue *= value; | |
504 | break; | |
505 | case DIV: | |
726f6388 | 506 | case MOD: |
ac50fbac CR |
507 | if (lvalue == INTMAX_MIN && value == -1) |
508 | lvalue = (op == DIV) ? INTMAX_MIN : 0; | |
509 | else | |
510 | #if HAVE_IMAXDIV | |
511 | { | |
512 | idiv = imaxdiv (lvalue, value); | |
513 | lvalue = (op == DIV) ? idiv.quot : idiv.rem; | |
514 | } | |
515 | #else | |
516 | lvalue = (op == DIV) ? lvalue / value : lvalue % value; | |
517 | #endif | |
726f6388 JA |
518 | break; |
519 | case PLUS: | |
520 | lvalue += value; | |
521 | break; | |
522 | case MINUS: | |
523 | lvalue -= value; | |
524 | break; | |
525 | case LSH: | |
526 | lvalue <<= value; | |
527 | break; | |
528 | case RSH: | |
529 | lvalue >>= value; | |
530 | break; | |
531 | case BAND: | |
532 | lvalue &= value; | |
533 | break; | |
534 | case BOR: | |
535 | lvalue |= value; | |
536 | break; | |
28ef6c31 JA |
537 | case BXOR: |
538 | lvalue ^= value; | |
539 | break; | |
726f6388 | 540 | default: |
d166f048 | 541 | free (lhs); |
b80f6443 | 542 | evalerror (_("bug: bad expassign token")); |
726f6388 JA |
543 | break; |
544 | } | |
545 | value = lvalue; | |
546 | } | |
547 | ||
548 | rhs = itos (value); | |
ccc6cda3 | 549 | if (noeval == 0) |
495aee44 | 550 | { |
ac50fbac | 551 | #if defined (ARRAY_VARS) |
495aee44 CR |
552 | if (lind != -1) |
553 | expr_bind_array_element (lhs, lind, rhs); | |
554 | else | |
ac50fbac | 555 | #endif |
495aee44 CR |
556 | expr_bind_variable (lhs, rhs); |
557 | } | |
ac50fbac CR |
558 | if (curlval.tokstr && curlval.tokstr == tokstr) |
559 | init_lvalue (&curlval); | |
560 | ||
726f6388 JA |
561 | free (rhs); |
562 | free (lhs); | |
d166f048 | 563 | FREE (tokstr); |
726f6388 JA |
564 | tokstr = (char *)NULL; /* For freeing on errors. */ |
565 | } | |
ac50fbac | 566 | |
726f6388 JA |
567 | return (value); |
568 | } | |
569 | ||
ccc6cda3 | 570 | /* Conditional expression (expr?expr:expr) */ |
7117c2d2 | 571 | static intmax_t |
ccc6cda3 JA |
572 | expcond () |
573 | { | |
7117c2d2 | 574 | intmax_t cval, val1, val2, rval; |
d166f048 JA |
575 | int set_noeval; |
576 | ||
577 | set_noeval = 0; | |
ccc6cda3 JA |
578 | rval = cval = explor (); |
579 | if (curtok == QUES) /* found conditional expr */ | |
580 | { | |
581 | readtok (); | |
582 | if (curtok == 0 || curtok == COL) | |
b80f6443 | 583 | evalerror (_("expression expected")); |
ccc6cda3 | 584 | if (cval == 0) |
d166f048 JA |
585 | { |
586 | set_noeval = 1; | |
587 | noeval++; | |
588 | } | |
f73dda09 | 589 | |
bb70624e | 590 | val1 = EXP_HIGHEST (); |
f73dda09 | 591 | |
d166f048 | 592 | if (set_noeval) |
28ef6c31 | 593 | noeval--; |
ccc6cda3 | 594 | if (curtok != COL) |
b80f6443 | 595 | evalerror (_("`:' expected for conditional expression")); |
ccc6cda3 JA |
596 | readtok (); |
597 | if (curtok == 0) | |
b80f6443 | 598 | evalerror (_("expression expected")); |
d166f048 | 599 | set_noeval = 0; |
ccc6cda3 | 600 | if (cval) |
d166f048 JA |
601 | { |
602 | set_noeval = 1; | |
603 | noeval++; | |
604 | } | |
f1be666c JA |
605 | |
606 | val2 = expcond (); | |
d166f048 | 607 | if (set_noeval) |
28ef6c31 | 608 | noeval--; |
ccc6cda3 JA |
609 | rval = cval ? val1 : val2; |
610 | lasttok = COND; | |
611 | } | |
612 | return rval; | |
613 | } | |
614 | ||
726f6388 | 615 | /* Logical OR. */ |
7117c2d2 | 616 | static intmax_t |
726f6388 JA |
617 | explor () |
618 | { | |
7117c2d2 | 619 | register intmax_t val1, val2; |
d166f048 | 620 | int set_noeval; |
726f6388 JA |
621 | |
622 | val1 = expland (); | |
623 | ||
624 | while (curtok == LOR) | |
625 | { | |
d166f048 | 626 | set_noeval = 0; |
ccc6cda3 | 627 | if (val1 != 0) |
d166f048 JA |
628 | { |
629 | noeval++; | |
630 | set_noeval = 1; | |
631 | } | |
632 | readtok (); | |
726f6388 | 633 | val2 = expland (); |
d166f048 | 634 | if (set_noeval) |
ccc6cda3 | 635 | noeval--; |
726f6388 | 636 | val1 = val1 || val2; |
d166f048 | 637 | lasttok = LOR; |
726f6388 JA |
638 | } |
639 | ||
640 | return (val1); | |
641 | } | |
642 | ||
643 | /* Logical AND. */ | |
7117c2d2 | 644 | static intmax_t |
726f6388 JA |
645 | expland () |
646 | { | |
7117c2d2 | 647 | register intmax_t val1, val2; |
d166f048 | 648 | int set_noeval; |
726f6388 JA |
649 | |
650 | val1 = expbor (); | |
651 | ||
652 | while (curtok == LAND) | |
653 | { | |
d166f048 | 654 | set_noeval = 0; |
ccc6cda3 | 655 | if (val1 == 0) |
d166f048 JA |
656 | { |
657 | set_noeval = 1; | |
658 | noeval++; | |
659 | } | |
660 | readtok (); | |
726f6388 | 661 | val2 = expbor (); |
d166f048 | 662 | if (set_noeval) |
ccc6cda3 | 663 | noeval--; |
726f6388 | 664 | val1 = val1 && val2; |
d166f048 | 665 | lasttok = LAND; |
726f6388 JA |
666 | } |
667 | ||
668 | return (val1); | |
669 | } | |
670 | ||
671 | /* Bitwise OR. */ | |
7117c2d2 | 672 | static intmax_t |
726f6388 JA |
673 | expbor () |
674 | { | |
7117c2d2 | 675 | register intmax_t val1, val2; |
726f6388 JA |
676 | |
677 | val1 = expbxor (); | |
678 | ||
679 | while (curtok == BOR) | |
680 | { | |
681 | readtok (); | |
682 | val2 = expbxor (); | |
683 | val1 = val1 | val2; | |
ac50fbac | 684 | lasttok = NUM; |
726f6388 JA |
685 | } |
686 | ||
687 | return (val1); | |
688 | } | |
689 | ||
690 | /* Bitwise XOR. */ | |
7117c2d2 | 691 | static intmax_t |
726f6388 JA |
692 | expbxor () |
693 | { | |
7117c2d2 | 694 | register intmax_t val1, val2; |
726f6388 JA |
695 | |
696 | val1 = expband (); | |
697 | ||
698 | while (curtok == BXOR) | |
699 | { | |
700 | readtok (); | |
701 | val2 = expband (); | |
702 | val1 = val1 ^ val2; | |
ac50fbac | 703 | lasttok = NUM; |
726f6388 JA |
704 | } |
705 | ||
706 | return (val1); | |
707 | } | |
708 | ||
709 | /* Bitwise AND. */ | |
7117c2d2 | 710 | static intmax_t |
726f6388 JA |
711 | expband () |
712 | { | |
7117c2d2 | 713 | register intmax_t val1, val2; |
726f6388 JA |
714 | |
715 | val1 = exp5 (); | |
716 | ||
717 | while (curtok == BAND) | |
718 | { | |
719 | readtok (); | |
720 | val2 = exp5 (); | |
721 | val1 = val1 & val2; | |
ac50fbac | 722 | lasttok = NUM; |
726f6388 JA |
723 | } |
724 | ||
725 | return (val1); | |
726 | } | |
727 | ||
7117c2d2 | 728 | static intmax_t |
726f6388 JA |
729 | exp5 () |
730 | { | |
7117c2d2 | 731 | register intmax_t val1, val2; |
726f6388 JA |
732 | |
733 | val1 = exp4 (); | |
734 | ||
735 | while ((curtok == EQEQ) || (curtok == NEQ)) | |
736 | { | |
737 | int op = curtok; | |
738 | ||
739 | readtok (); | |
740 | val2 = exp4 (); | |
741 | if (op == EQEQ) | |
742 | val1 = (val1 == val2); | |
743 | else if (op == NEQ) | |
744 | val1 = (val1 != val2); | |
ac50fbac | 745 | lasttok = NUM; |
726f6388 JA |
746 | } |
747 | return (val1); | |
748 | } | |
749 | ||
7117c2d2 | 750 | static intmax_t |
726f6388 JA |
751 | exp4 () |
752 | { | |
7117c2d2 | 753 | register intmax_t val1, val2; |
726f6388 JA |
754 | |
755 | val1 = expshift (); | |
756 | while ((curtok == LEQ) || | |
757 | (curtok == GEQ) || | |
758 | (curtok == LT) || | |
759 | (curtok == GT)) | |
760 | { | |
761 | int op = curtok; | |
762 | ||
763 | readtok (); | |
764 | val2 = expshift (); | |
765 | ||
766 | if (op == LEQ) | |
767 | val1 = val1 <= val2; | |
768 | else if (op == GEQ) | |
769 | val1 = val1 >= val2; | |
770 | else if (op == LT) | |
771 | val1 = val1 < val2; | |
d166f048 | 772 | else /* (op == GT) */ |
726f6388 | 773 | val1 = val1 > val2; |
ac50fbac | 774 | lasttok = NUM; |
726f6388 JA |
775 | } |
776 | return (val1); | |
777 | } | |
778 | ||
779 | /* Left and right shifts. */ | |
7117c2d2 | 780 | static intmax_t |
726f6388 JA |
781 | expshift () |
782 | { | |
7117c2d2 | 783 | register intmax_t val1, val2; |
726f6388 JA |
784 | |
785 | val1 = exp3 (); | |
786 | ||
787 | while ((curtok == LSH) || (curtok == RSH)) | |
788 | { | |
789 | int op = curtok; | |
790 | ||
791 | readtok (); | |
792 | val2 = exp3 (); | |
793 | ||
794 | if (op == LSH) | |
795 | val1 = val1 << val2; | |
796 | else | |
797 | val1 = val1 >> val2; | |
ac50fbac | 798 | lasttok = NUM; |
726f6388 JA |
799 | } |
800 | ||
801 | return (val1); | |
802 | } | |
803 | ||
7117c2d2 | 804 | static intmax_t |
726f6388 JA |
805 | exp3 () |
806 | { | |
7117c2d2 | 807 | register intmax_t val1, val2; |
726f6388 JA |
808 | |
809 | val1 = exp2 (); | |
810 | ||
811 | while ((curtok == PLUS) || (curtok == MINUS)) | |
812 | { | |
813 | int op = curtok; | |
814 | ||
815 | readtok (); | |
816 | val2 = exp2 (); | |
817 | ||
818 | if (op == PLUS) | |
819 | val1 += val2; | |
820 | else if (op == MINUS) | |
821 | val1 -= val2; | |
ac50fbac | 822 | lasttok = NUM; |
726f6388 JA |
823 | } |
824 | return (val1); | |
825 | } | |
826 | ||
7117c2d2 | 827 | static intmax_t |
726f6388 JA |
828 | exp2 () |
829 | { | |
7117c2d2 | 830 | register intmax_t val1, val2; |
ac50fbac CR |
831 | #if defined (HAVE_IMAXDIV) |
832 | imaxdiv_t idiv; | |
833 | #endif | |
726f6388 | 834 | |
cce855bc | 835 | val1 = exppower (); |
726f6388 JA |
836 | |
837 | while ((curtok == MUL) || | |
28ef6c31 JA |
838 | (curtok == DIV) || |
839 | (curtok == MOD)) | |
726f6388 JA |
840 | { |
841 | int op = curtok; | |
ac50fbac | 842 | char *stp, *sltp; |
726f6388 | 843 | |
ac50fbac | 844 | stp = tp; |
726f6388 JA |
845 | readtok (); |
846 | ||
cce855bc | 847 | val2 = exppower (); |
726f6388 | 848 | |
ac50fbac | 849 | /* Handle division by 0 and twos-complement arithmetic overflow */ |
726f6388 | 850 | if (((op == DIV) || (op == MOD)) && (val2 == 0)) |
cf391c36 CR |
851 | { |
852 | if (noeval == 0) | |
ac50fbac CR |
853 | { |
854 | sltp = lasttp; | |
855 | lasttp = stp; | |
856 | while (lasttp && *lasttp && whitespace (*lasttp)) | |
857 | lasttp++; | |
858 | evalerror (_("division by 0")); | |
859 | lasttp = sltp; | |
860 | } | |
cf391c36 CR |
861 | else |
862 | val2 = 1; | |
863 | } | |
ac50fbac CR |
864 | else if (op == MOD && val1 == INTMAX_MIN && val2 == -1) |
865 | { | |
866 | val1 = 0; | |
867 | continue; | |
868 | } | |
869 | else if (op == DIV && val1 == INTMAX_MIN && val2 == -1) | |
870 | val2 = 1; | |
726f6388 JA |
871 | |
872 | if (op == MUL) | |
28ef6c31 | 873 | val1 *= val2; |
ac50fbac CR |
874 | else if (op == DIV || op == MOD) |
875 | #if defined (HAVE_IMAXDIV) | |
876 | { | |
877 | idiv = imaxdiv (val1, val2); | |
878 | val1 = (op == DIV) ? idiv.quot : idiv.rem; | |
879 | } | |
880 | #else | |
881 | val1 = (op == DIV) ? val1 / val2 : val1 % val2; | |
882 | #endif | |
883 | lasttok = NUM; | |
726f6388 JA |
884 | } |
885 | return (val1); | |
886 | } | |
887 | ||
ac50fbac CR |
888 | static intmax_t |
889 | ipow (base, exp) | |
890 | intmax_t base, exp; | |
891 | { | |
892 | intmax_t result; | |
893 | ||
894 | result = 1; | |
895 | while (exp) | |
896 | { | |
897 | if (exp & 1) | |
898 | result *= base; | |
899 | exp >>= 1; | |
900 | base *= base; | |
901 | } | |
902 | return result; | |
903 | } | |
904 | ||
7117c2d2 | 905 | static intmax_t |
cce855bc JA |
906 | exppower () |
907 | { | |
7117c2d2 | 908 | register intmax_t val1, val2, c; |
cce855bc JA |
909 | |
910 | val1 = exp1 (); | |
b80f6443 | 911 | while (curtok == POWER) |
cce855bc JA |
912 | { |
913 | readtok (); | |
95732b49 | 914 | val2 = exppower (); /* exponentiation is right-associative */ |
ac50fbac | 915 | lasttok = NUM; |
cce855bc | 916 | if (val2 == 0) |
f73dda09 | 917 | return (1); |
bb70624e | 918 | if (val2 < 0) |
b80f6443 | 919 | evalerror (_("exponent less than 0")); |
ac50fbac | 920 | val1 = ipow (val1, val2); |
cce855bc JA |
921 | } |
922 | return (val1); | |
923 | } | |
924 | ||
7117c2d2 | 925 | static intmax_t |
726f6388 JA |
926 | exp1 () |
927 | { | |
7117c2d2 | 928 | register intmax_t val; |
726f6388 JA |
929 | |
930 | if (curtok == NOT) | |
931 | { | |
932 | readtok (); | |
933 | val = !exp1 (); | |
ac50fbac | 934 | lasttok = NUM; |
726f6388 JA |
935 | } |
936 | else if (curtok == BNOT) | |
937 | { | |
938 | readtok (); | |
939 | val = ~exp1 (); | |
ac50fbac | 940 | lasttok = NUM; |
726f6388 | 941 | } |
495aee44 CR |
942 | else if (curtok == MINUS) |
943 | { | |
944 | readtok (); | |
945 | val = - exp1 (); | |
ac50fbac | 946 | lasttok = NUM; |
495aee44 CR |
947 | } |
948 | else if (curtok == PLUS) | |
949 | { | |
950 | readtok (); | |
951 | val = exp1 (); | |
ac50fbac | 952 | lasttok = NUM; |
495aee44 | 953 | } |
726f6388 JA |
954 | else |
955 | val = exp0 (); | |
956 | ||
957 | return (val); | |
958 | } | |
959 | ||
7117c2d2 | 960 | static intmax_t |
726f6388 JA |
961 | exp0 () |
962 | { | |
7117c2d2 | 963 | register intmax_t val = 0, v2; |
bb70624e JA |
964 | char *vincdec; |
965 | int stok; | |
b80f6443 | 966 | EXPR_CONTEXT ec; |
bb70624e JA |
967 | |
968 | /* XXX - might need additional logic here to decide whether or not | |
969 | pre-increment or pre-decrement is legal at this point. */ | |
970 | if (curtok == PREINC || curtok == PREDEC) | |
971 | { | |
972 | stok = lasttok = curtok; | |
973 | readtok (); | |
974 | if (curtok != STR) | |
28ef6c31 | 975 | /* readtok() catches this */ |
b80f6443 | 976 | evalerror (_("identifier expected after pre-increment or pre-decrement")); |
726f6388 | 977 | |
bb70624e JA |
978 | v2 = tokval + ((stok == PREINC) ? 1 : -1); |
979 | vincdec = itos (v2); | |
980 | if (noeval == 0) | |
495aee44 | 981 | { |
ac50fbac | 982 | #if defined (ARRAY_VARS) |
495aee44 CR |
983 | if (curlval.ind != -1) |
984 | expr_bind_array_element (curlval.tokstr, curlval.ind, vincdec); | |
985 | else | |
ac50fbac | 986 | #endif |
495aee44 CR |
987 | expr_bind_variable (tokstr, vincdec); |
988 | } | |
bb70624e JA |
989 | free (vincdec); |
990 | val = v2; | |
991 | ||
992 | curtok = NUM; /* make sure --x=7 is flagged as an error */ | |
993 | readtok (); | |
994 | } | |
726f6388 JA |
995 | else if (curtok == LPAR) |
996 | { | |
ac50fbac | 997 | /* XXX - save curlval here? Or entire expression context? */ |
726f6388 | 998 | readtok (); |
bb70624e | 999 | val = EXP_HIGHEST (); |
726f6388 | 1000 | |
b80f6443 JA |
1001 | if (curtok != RPAR) /* ( */ |
1002 | evalerror (_("missing `)'")); | |
726f6388 JA |
1003 | |
1004 | /* Skip over closing paren. */ | |
1005 | readtok (); | |
1006 | } | |
1007 | else if ((curtok == NUM) || (curtok == STR)) | |
1008 | { | |
1009 | val = tokval; | |
b80f6443 | 1010 | if (curtok == STR) |
bb70624e | 1011 | { |
b80f6443 JA |
1012 | SAVETOK (&ec); |
1013 | tokstr = (char *)NULL; /* keep it from being freed */ | |
1014 | noeval = 1; | |
1015 | readtok (); | |
1016 | stok = curtok; | |
1017 | ||
bb70624e | 1018 | /* post-increment or post-decrement */ |
b80f6443 JA |
1019 | if (stok == POSTINC || stok == POSTDEC) |
1020 | { | |
1021 | /* restore certain portions of EC */ | |
1022 | tokstr = ec.tokstr; | |
1023 | noeval = ec.noeval; | |
495aee44 | 1024 | curlval = ec.lval; |
b80f6443 JA |
1025 | lasttok = STR; /* ec.curtok */ |
1026 | ||
1027 | v2 = val + ((stok == POSTINC) ? 1 : -1); | |
1028 | vincdec = itos (v2); | |
1029 | if (noeval == 0) | |
495aee44 | 1030 | { |
ac50fbac | 1031 | #if defined (ARRAY_VARS) |
495aee44 CR |
1032 | if (curlval.ind != -1) |
1033 | expr_bind_array_element (curlval.tokstr, curlval.ind, vincdec); | |
1034 | else | |
ac50fbac | 1035 | #endif |
495aee44 CR |
1036 | expr_bind_variable (tokstr, vincdec); |
1037 | } | |
b80f6443 JA |
1038 | free (vincdec); |
1039 | curtok = NUM; /* make sure x++=7 is flagged as an error */ | |
1040 | } | |
1041 | else | |
1042 | { | |
ac50fbac | 1043 | /* XXX - watch out for pointer aliasing issues here */ |
b80f6443 JA |
1044 | if (stok == STR) /* free new tokstr before old one is restored */ |
1045 | FREE (tokstr); | |
1046 | RESTORETOK (&ec); | |
1047 | } | |
bb70624e JA |
1048 | } |
1049 | ||
726f6388 JA |
1050 | readtok (); |
1051 | } | |
1052 | else | |
b80f6443 | 1053 | evalerror (_("syntax error: operand expected")); |
726f6388 JA |
1054 | |
1055 | return (val); | |
1056 | } | |
1057 | ||
495aee44 CR |
1058 | static void |
1059 | init_lvalue (lv) | |
1060 | struct lvalue *lv; | |
1061 | { | |
1062 | lv->tokstr = 0; | |
1063 | lv->tokvar = 0; | |
1064 | lv->tokval = lv->ind = -1; | |
1065 | } | |
1066 | ||
1067 | static struct lvalue * | |
1068 | alloc_lvalue () | |
1069 | { | |
1070 | struct lvalue *lv; | |
1071 | ||
1072 | lv = xmalloc (sizeof (struct lvalue)); | |
1073 | init_lvalue (lv); | |
1074 | return (lv); | |
1075 | } | |
1076 | ||
1077 | static void | |
1078 | free_lvalue (lv) | |
1079 | struct lvalue *lv; | |
1080 | { | |
1081 | free (lv); /* should be inlined */ | |
1082 | } | |
1083 | ||
7117c2d2 | 1084 | static intmax_t |
495aee44 | 1085 | expr_streval (tok, e, lvalue) |
7117c2d2 JA |
1086 | char *tok; |
1087 | int e; | |
495aee44 | 1088 | struct lvalue *lvalue; |
7117c2d2 JA |
1089 | { |
1090 | SHELL_VAR *v; | |
1091 | char *value; | |
1092 | intmax_t tval; | |
495aee44 CR |
1093 | #if defined (ARRAY_VARS) |
1094 | arrayind_t ind; | |
1095 | #endif | |
7117c2d2 | 1096 | |
11d0fdf7 CR |
1097 | /*itrace("expr_streval: %s: noeval = %d", tok, noeval);*/ |
1098 | /* If we are suppressing evaluation, just short-circuit here instead of | |
1099 | going through the rest of the evaluator. */ | |
1100 | if (noeval) | |
1101 | return (0); | |
1102 | ||
7117c2d2 JA |
1103 | /* [[[[[ */ |
1104 | #if defined (ARRAY_VARS) | |
1105 | v = (e == ']') ? array_variable_part (tok, (char **)0, (int *)0) : find_variable (tok); | |
1106 | #else | |
1107 | v = find_variable (tok); | |
1108 | #endif | |
1109 | ||
1110 | if ((v == 0 || invisible_p (v)) && unbound_vars_is_error) | |
1111 | { | |
1112 | #if defined (ARRAY_VARS) | |
1113 | value = (e == ']') ? array_variable_name (tok, (char **)0, (int *)0) : tok; | |
1114 | #else | |
1115 | value = tok; | |
1116 | #endif | |
1117 | ||
0001803f | 1118 | last_command_exit_value = EXECUTION_FAILURE; |
7117c2d2 JA |
1119 | err_unboundvar (value); |
1120 | ||
1121 | #if defined (ARRAY_VARS) | |
1122 | if (e == ']') | |
1123 | FREE (value); /* array_variable_name returns new memory */ | |
1124 | #endif | |
1125 | ||
1126 | if (interactive_shell) | |
1127 | { | |
1128 | expr_unwind (); | |
f1be666c | 1129 | top_level_cleanup (); |
7117c2d2 JA |
1130 | jump_to_top_level (DISCARD); |
1131 | } | |
1132 | else | |
1133 | jump_to_top_level (FORCE_EOF); | |
1134 | } | |
1135 | ||
1136 | #if defined (ARRAY_VARS) | |
ac50fbac | 1137 | ind = -1; |
7117c2d2 JA |
1138 | /* Second argument of 0 to get_array_value means that we don't allow |
1139 | references like array[@]. In this case, get_array_value is just | |
1140 | like get_variable_value in that it does not return newly-allocated | |
1141 | memory or quote the results. */ | |
495aee44 | 1142 | value = (e == ']') ? get_array_value (tok, 0, (int *)NULL, &ind) : get_variable_value (v); |
7117c2d2 JA |
1143 | #else |
1144 | value = get_variable_value (v); | |
1145 | #endif | |
1146 | ||
1147 | tval = (value && *value) ? subexpr (value) : 0; | |
1148 | ||
495aee44 CR |
1149 | if (lvalue) |
1150 | { | |
1151 | lvalue->tokstr = tok; /* XXX */ | |
1152 | lvalue->tokval = tval; | |
1153 | lvalue->tokvar = v; /* XXX */ | |
ac50fbac | 1154 | #if defined (ARRAY_VARS) |
495aee44 | 1155 | lvalue->ind = ind; |
ac50fbac CR |
1156 | #else |
1157 | lvalue->ind = -1; | |
1158 | #endif | |
495aee44 CR |
1159 | } |
1160 | ||
7117c2d2 JA |
1161 | return (tval); |
1162 | } | |
1163 | ||
0628567a JA |
1164 | static int |
1165 | _is_multiop (c) | |
1166 | int c; | |
1167 | { | |
1168 | switch (c) | |
1169 | { | |
1170 | case EQEQ: | |
1171 | case NEQ: | |
1172 | case LEQ: | |
1173 | case GEQ: | |
1174 | case LAND: | |
1175 | case LOR: | |
1176 | case LSH: | |
1177 | case RSH: | |
1178 | case OP_ASSIGN: | |
1179 | case COND: | |
1180 | case POWER: | |
1181 | case PREINC: | |
1182 | case PREDEC: | |
1183 | case POSTINC: | |
1184 | case POSTDEC: | |
1185 | return 1; | |
1186 | default: | |
1187 | return 0; | |
1188 | } | |
1189 | } | |
1190 | ||
1191 | static int | |
1192 | _is_arithop (c) | |
1193 | int c; | |
1194 | { | |
1195 | switch (c) | |
1196 | { | |
1197 | case EQ: | |
1198 | case GT: | |
1199 | case LT: | |
1200 | case PLUS: | |
1201 | case MINUS: | |
1202 | case MUL: | |
1203 | case DIV: | |
1204 | case MOD: | |
1205 | case NOT: | |
1206 | case LPAR: | |
1207 | case RPAR: | |
1208 | case BAND: | |
1209 | case BOR: | |
1210 | case BXOR: | |
1211 | case BNOT: | |
1212 | return 1; /* operator tokens */ | |
1213 | case QUES: | |
1214 | case COL: | |
1215 | case COMMA: | |
1216 | return 1; /* questionable */ | |
1217 | default: | |
1218 | return 0; /* anything else is invalid */ | |
1219 | } | |
1220 | } | |
1221 | ||
726f6388 JA |
1222 | /* Lexical analyzer/token reader for the expression evaluator. Reads the |
1223 | next token and puts its value into curtok, while advancing past it. | |
1224 | Updates value of tp. May also set tokval (for number) or tokstr (for | |
1225 | string). */ | |
1226 | static void | |
1227 | readtok () | |
1228 | { | |
b80f6443 | 1229 | register char *cp, *xp; |
f73dda09 JA |
1230 | register unsigned char c, c1; |
1231 | register int e; | |
495aee44 | 1232 | struct lvalue lval; |
726f6388 JA |
1233 | |
1234 | /* Skip leading whitespace. */ | |
ccc6cda3 JA |
1235 | cp = tp; |
1236 | c = e = 0; | |
726f6388 JA |
1237 | while (cp && (c = *cp) && (cr_whitespace (c))) |
1238 | cp++; | |
1239 | ||
1240 | if (c) | |
1241 | cp++; | |
ccc6cda3 | 1242 | |
726f6388 JA |
1243 | if (c == '\0') |
1244 | { | |
1245 | lasttok = curtok; | |
1246 | curtok = 0; | |
1247 | tp = cp; | |
1248 | return; | |
1249 | } | |
3185942a | 1250 | lasttp = tp = cp - 1; |
726f6388 | 1251 | |
ccc6cda3 | 1252 | if (legal_variable_starter (c)) |
726f6388 | 1253 | { |
bb70624e | 1254 | /* variable names not preceded with a dollar sign are shell variables. */ |
7117c2d2 | 1255 | char *savecp; |
bb70624e JA |
1256 | EXPR_CONTEXT ec; |
1257 | int peektok; | |
726f6388 | 1258 | |
ccc6cda3 | 1259 | while (legal_variable_char (c)) |
726f6388 JA |
1260 | c = *cp++; |
1261 | ||
1262 | c = *--cp; | |
ccc6cda3 JA |
1263 | |
1264 | #if defined (ARRAY_VARS) | |
1265 | if (c == '[') | |
1266 | { | |
0001803f | 1267 | e = skipsubscript (cp, 0, 0); |
ccc6cda3 JA |
1268 | if (cp[e] == ']') |
1269 | { | |
1270 | cp += e + 1; | |
1271 | c = *cp; | |
1272 | e = ']'; | |
1273 | } | |
1274 | else | |
b80f6443 | 1275 | evalerror (bash_badsub_errmsg); |
ccc6cda3 JA |
1276 | } |
1277 | #endif /* ARRAY_VARS */ | |
1278 | ||
726f6388 | 1279 | *cp = '\0'; |
11d0fdf7 CR |
1280 | /* XXX - watch out for pointer aliasing issues here */ |
1281 | if (curlval.tokstr && curlval.tokstr == tokstr) | |
1282 | init_lvalue (&curlval); | |
1283 | ||
ccc6cda3 | 1284 | FREE (tokstr); |
726f6388 | 1285 | tokstr = savestring (tp); |
bb70624e | 1286 | *cp = c; |
ccc6cda3 | 1287 | |
495aee44 | 1288 | /* XXX - make peektok part of saved token state? */ |
bb70624e JA |
1289 | SAVETOK (&ec); |
1290 | tokstr = (char *)NULL; /* keep it from being freed */ | |
1291 | tp = savecp = cp; | |
1292 | noeval = 1; | |
b80f6443 | 1293 | curtok = STR; |
bb70624e JA |
1294 | readtok (); |
1295 | peektok = curtok; | |
1296 | if (peektok == STR) /* free new tokstr before old one is restored */ | |
1297 | FREE (tokstr); | |
1298 | RESTORETOK (&ec); | |
1299 | cp = savecp; | |
1300 | ||
1301 | /* The tests for PREINC and PREDEC aren't strictly correct, but they | |
1302 | preserve old behavior if a construct like --x=9 is given. */ | |
1303 | if (lasttok == PREINC || lasttok == PREDEC || peektok != EQ) | |
495aee44 CR |
1304 | { |
1305 | lastlval = curlval; | |
1306 | tokval = expr_streval (tokstr, e, &curlval); | |
1307 | } | |
bb70624e | 1308 | else |
28ef6c31 | 1309 | tokval = 0; |
726f6388 | 1310 | |
726f6388 JA |
1311 | lasttok = curtok; |
1312 | curtok = STR; | |
1313 | } | |
f73dda09 | 1314 | else if (DIGIT(c)) |
726f6388 | 1315 | { |
f73dda09 | 1316 | while (ISALNUM (c) || c == '#' || c == '@' || c == '_') |
726f6388 JA |
1317 | c = *cp++; |
1318 | ||
1319 | c = *--cp; | |
1320 | *cp = '\0'; | |
1321 | ||
1322 | tokval = strlong (tp); | |
1323 | *cp = c; | |
1324 | lasttok = curtok; | |
1325 | curtok = NUM; | |
1326 | } | |
1327 | else | |
1328 | { | |
1329 | c1 = *cp++; | |
ccc6cda3 | 1330 | if ((c == EQ) && (c1 == EQ)) |
726f6388 JA |
1331 | c = EQEQ; |
1332 | else if ((c == NOT) && (c1 == EQ)) | |
1333 | c = NEQ; | |
1334 | else if ((c == GT) && (c1 == EQ)) | |
1335 | c = GEQ; | |
1336 | else if ((c == LT) && (c1 == EQ)) | |
1337 | c = LEQ; | |
1338 | else if ((c == LT) && (c1 == LT)) | |
1339 | { | |
1340 | if (*cp == '=') /* a <<= b */ | |
1341 | { | |
1342 | assigntok = LSH; | |
1343 | c = OP_ASSIGN; | |
1344 | cp++; | |
1345 | } | |
1346 | else | |
1347 | c = LSH; | |
1348 | } | |
1349 | else if ((c == GT) && (c1 == GT)) | |
1350 | { | |
1351 | if (*cp == '=') | |
1352 | { | |
1353 | assigntok = RSH; /* a >>= b */ | |
1354 | c = OP_ASSIGN; | |
1355 | cp++; | |
1356 | } | |
1357 | else | |
1358 | c = RSH; | |
1359 | } | |
1360 | else if ((c == BAND) && (c1 == BAND)) | |
1361 | c = LAND; | |
1362 | else if ((c == BOR) && (c1 == BOR)) | |
1363 | c = LOR; | |
cce855bc | 1364 | else if ((c == '*') && (c1 == '*')) |
28ef6c31 | 1365 | c = POWER; |
b80f6443 JA |
1366 | else if ((c == '-' || c == '+') && c1 == c && curtok == STR) |
1367 | c = (c == '-') ? POSTDEC : POSTINC; | |
1368 | else if ((c == '-' || c == '+') && c1 == c) | |
1369 | { | |
1370 | /* Quickly scan forward to see if this is followed by optional | |
1371 | whitespace and an identifier. */ | |
1372 | xp = cp; | |
1373 | while (xp && *xp && cr_whitespace (*xp)) | |
1374 | xp++; | |
1375 | if (legal_variable_starter ((unsigned char)*xp)) | |
1376 | c = (c == '-') ? PREDEC : PREINC; | |
1377 | else | |
1378 | cp--; /* not preinc or predec, so unget the character */ | |
1379 | } | |
28ef6c31 | 1380 | else if (c1 == EQ && member (c, "*/%+-&^|")) |
726f6388 JA |
1381 | { |
1382 | assigntok = c; /* a OP= b */ | |
1383 | c = OP_ASSIGN; | |
1384 | } | |
0628567a JA |
1385 | else if (_is_arithop (c) == 0) |
1386 | { | |
1387 | cp--; | |
1388 | /* use curtok, since it hasn't been copied to lasttok yet */ | |
1389 | if (curtok == 0 || _is_arithop (curtok) || _is_multiop (curtok)) | |
1390 | evalerror (_("syntax error: operand expected")); | |
1391 | else | |
1392 | evalerror (_("syntax error: invalid arithmetic operator")); | |
1393 | } | |
726f6388 JA |
1394 | else |
1395 | cp--; /* `unget' the character */ | |
0628567a JA |
1396 | |
1397 | /* Should check here to make sure that the current character is one | |
1398 | of the recognized operators and flag an error if not. Could create | |
1399 | a character map the first time through and check it on subsequent | |
1400 | calls. */ | |
726f6388 JA |
1401 | lasttok = curtok; |
1402 | curtok = c; | |
1403 | } | |
1404 | tp = cp; | |
1405 | } | |
1406 | ||
1407 | static void | |
1408 | evalerror (msg) | |
3185942a | 1409 | const char *msg; |
726f6388 JA |
1410 | { |
1411 | char *name, *t; | |
1412 | ||
1413 | name = this_command_name; | |
726f6388 JA |
1414 | for (t = expression; whitespace (*t); t++) |
1415 | ; | |
3185942a | 1416 | internal_error (_("%s%s%s: %s (error token is \"%s\")"), |
ccc6cda3 JA |
1417 | name ? name : "", name ? ": " : "", t, |
1418 | msg, (lasttp && *lasttp) ? lasttp : ""); | |
726f6388 JA |
1419 | longjmp (evalbuf, 1); |
1420 | } | |
1421 | ||
7117c2d2 | 1422 | /* Convert a string to an intmax_t integer, with an arbitrary base. |
726f6388 | 1423 | 0nnn -> base 8 |
cce855bc | 1424 | 0[Xx]nn -> base 16 |
ccc6cda3 JA |
1425 | Anything else: [base#]number (this is implemented to match ksh93) |
1426 | ||
1427 | Base may be >=2 and <=64. If base is <= 36, the numbers are drawn | |
1428 | from [0-9][a-zA-Z], and lowercase and uppercase letters may be used | |
1429 | interchangably. If base is > 36 and <= 64, the numbers are drawn | |
95732b49 | 1430 | from [0-9][a-z][A-Z]_@ (a = 10, z = 35, A = 36, Z = 61, @ = 62, _ = 63 -- |
ccc6cda3 JA |
1431 | you get the picture). */ |
1432 | ||
7117c2d2 | 1433 | static intmax_t |
726f6388 JA |
1434 | strlong (num) |
1435 | char *num; | |
1436 | { | |
ccc6cda3 | 1437 | register char *s; |
f73dda09 | 1438 | register unsigned char c; |
ccc6cda3 | 1439 | int base, foundbase; |
7117c2d2 | 1440 | intmax_t val; |
726f6388 | 1441 | |
ccc6cda3 | 1442 | s = num; |
726f6388 | 1443 | |
ccc6cda3 JA |
1444 | base = 10; |
1445 | foundbase = 0; | |
726f6388 JA |
1446 | if (*s == '0') |
1447 | { | |
1448 | s++; | |
1449 | ||
f73dda09 JA |
1450 | if (*s == '\0') |
1451 | return 0; | |
ccc6cda3 | 1452 | |
726f6388 JA |
1453 | /* Base 16? */ |
1454 | if (*s == 'x' || *s == 'X') | |
1455 | { | |
1456 | base = 16; | |
1457 | s++; | |
1458 | } | |
1459 | else | |
1460 | base = 8; | |
ccc6cda3 | 1461 | foundbase++; |
726f6388 JA |
1462 | } |
1463 | ||
f73dda09 | 1464 | val = 0; |
726f6388 JA |
1465 | for (c = *s++; c; c = *s++) |
1466 | { | |
1467 | if (c == '#') | |
1468 | { | |
ccc6cda3 | 1469 | if (foundbase) |
b80f6443 | 1470 | evalerror (_("invalid number")); |
ccc6cda3 | 1471 | |
ccc6cda3 | 1472 | /* Illegal base specifications raise an evaluation error. */ |
f73dda09 | 1473 | if (val < 2 || val > 64) |
b80f6443 | 1474 | evalerror (_("invalid arithmetic base")); |
726f6388 | 1475 | |
f73dda09 JA |
1476 | base = val; |
1477 | val = 0; | |
ccc6cda3 JA |
1478 | foundbase++; |
1479 | } | |
f73dda09 | 1480 | else if (ISALNUM(c) || (c == '_') || (c == '@')) |
ccc6cda3 | 1481 | { |
f73dda09 JA |
1482 | if (DIGIT(c)) |
1483 | c = TODIGIT(c); | |
ccc6cda3 JA |
1484 | else if (c >= 'a' && c <= 'z') |
1485 | c -= 'a' - 10; | |
1486 | else if (c >= 'A' && c <= 'Z') | |
1487 | c -= 'A' - ((base <= 36) ? 10 : 36); | |
ccc6cda3 | 1488 | else if (c == '@') |
f73dda09 JA |
1489 | c = 62; |
1490 | else if (c == '_') | |
ccc6cda3 JA |
1491 | c = 63; |
1492 | ||
1493 | if (c >= base) | |
b80f6443 | 1494 | evalerror (_("value too great for base")); |
ccc6cda3 JA |
1495 | |
1496 | val = (val * base) + c; | |
726f6388 JA |
1497 | } |
1498 | else | |
ccc6cda3 | 1499 | break; |
726f6388 | 1500 | } |
95732b49 | 1501 | |
726f6388 JA |
1502 | return (val); |
1503 | } | |
1504 | ||
1505 | #if defined (EXPR_TEST) | |
f73dda09 | 1506 | void * |
726f6388 JA |
1507 | xmalloc (n) |
1508 | int n; | |
1509 | { | |
1510 | return (malloc (n)); | |
1511 | } | |
1512 | ||
f73dda09 | 1513 | void * |
726f6388 JA |
1514 | xrealloc (s, n) |
1515 | char *s; | |
1516 | int n; | |
1517 | { | |
1518 | return (realloc (s, n)); | |
1519 | } | |
1520 | ||
1521 | SHELL_VAR *find_variable () { return 0;} | |
1522 | SHELL_VAR *bind_variable () { return 0; } | |
1523 | ||
1524 | char *get_string_value () { return 0; } | |
1525 | ||
ccc6cda3 | 1526 | procenv_t top_level; |
726f6388 JA |
1527 | |
1528 | main (argc, argv) | |
1529 | int argc; | |
1530 | char **argv; | |
1531 | { | |
1532 | register int i; | |
7117c2d2 | 1533 | intmax_t v; |
d166f048 | 1534 | int expok; |
726f6388 JA |
1535 | |
1536 | if (setjmp (top_level)) | |
1537 | exit (0); | |
1538 | ||
1539 | for (i = 1; i < argc; i++) | |
1540 | { | |
d166f048 JA |
1541 | v = evalexp (argv[i], &expok); |
1542 | if (expok == 0) | |
3185942a | 1543 | fprintf (stderr, _("%s: expression error\n"), argv[i]); |
d166f048 | 1544 | else |
28ef6c31 | 1545 | printf ("'%s' -> %ld\n", argv[i], v); |
726f6388 JA |
1546 | } |
1547 | exit (0); | |
1548 | } | |
1549 | ||
1550 | int | |
1551 | builtin_error (format, arg1, arg2, arg3, arg4, arg5) | |
1552 | char *format; | |
1553 | { | |
1554 | fprintf (stderr, "expr: "); | |
1555 | fprintf (stderr, format, arg1, arg2, arg3, arg4, arg5); | |
1556 | fprintf (stderr, "\n"); | |
1557 | return 0; | |
1558 | } | |
1559 | ||
1560 | char * | |
1561 | itos (n) | |
7117c2d2 | 1562 | intmax_t n; |
726f6388 JA |
1563 | { |
1564 | return ("42"); | |
1565 | } | |
1566 | ||
1567 | #endif /* EXPR_TEST */ |