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Diffstat (limited to 'gnu/usr.bin/awk/eval.c')
| -rw-r--r-- | gnu/usr.bin/awk/eval.c | 1225 |
1 files changed, 1225 insertions, 0 deletions
diff --git a/gnu/usr.bin/awk/eval.c b/gnu/usr.bin/awk/eval.c new file mode 100644 index 0000000..f640f37 --- /dev/null +++ b/gnu/usr.bin/awk/eval.c @@ -0,0 +1,1225 @@ +/* + * eval.c - gawk parse tree interpreter + */ + +/* + * Copyright (C) 1986, 1988, 1989, 1991, 1992 the Free Software Foundation, Inc. + * + * This file is part of GAWK, the GNU implementation of the + * AWK Progamming Language. + * + * GAWK 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 of the License, or + * (at your option) any later version. + * + * GAWK 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 GAWK; see the file COPYING. If not, write to + * the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + */ + +#include "awk.h" + +extern double pow P((double x, double y)); +extern double modf P((double x, double *yp)); +extern double fmod P((double x, double y)); + +static int eval_condition P((NODE *tree)); +static NODE *op_assign P((NODE *tree)); +static NODE *func_call P((NODE *name, NODE *arg_list)); +static NODE *match_op P((NODE *tree)); + +NODE *_t; /* used as a temporary in macros */ +#ifdef MSDOS +double _msc51bug; /* to get around a bug in MSC 5.1 */ +#endif +NODE *ret_node; +int OFSlen; +int ORSlen; +int OFMTidx; +int CONVFMTidx; + +/* Macros and variables to save and restore function and loop bindings */ +/* + * the val variable allows return/continue/break-out-of-context to be + * caught and diagnosed + */ +#define PUSH_BINDING(stack, x, val) (memcpy ((char *)(stack), (char *)(x), sizeof (jmp_buf)), val++) +#define RESTORE_BINDING(stack, x, val) (memcpy ((char *)(x), (char *)(stack), sizeof (jmp_buf)), val--) + +static jmp_buf loop_tag; /* always the current binding */ +static int loop_tag_valid = 0; /* nonzero when loop_tag valid */ +static int func_tag_valid = 0; +static jmp_buf func_tag; +extern int exiting, exit_val; + +/* + * This table is used by the regexp routines to do case independant + * matching. Basically, every ascii character maps to itself, except + * uppercase letters map to lower case ones. This table has 256 + * entries, which may be overkill. Note also that if the system this + * is compiled on doesn't use 7-bit ascii, casetable[] should not be + * defined to the linker, so gawk should not load. + * + * Do NOT make this array static, it is used in several spots, not + * just in this file. + */ +#if 'a' == 97 /* it's ascii */ +char casetable[] = { + '\000', '\001', '\002', '\003', '\004', '\005', '\006', '\007', + '\010', '\011', '\012', '\013', '\014', '\015', '\016', '\017', + '\020', '\021', '\022', '\023', '\024', '\025', '\026', '\027', + '\030', '\031', '\032', '\033', '\034', '\035', '\036', '\037', + /* ' ' '!' '"' '#' '$' '%' '&' ''' */ + '\040', '\041', '\042', '\043', '\044', '\045', '\046', '\047', + /* '(' ')' '*' '+' ',' '-' '.' '/' */ + '\050', '\051', '\052', '\053', '\054', '\055', '\056', '\057', + /* '0' '1' '2' '3' '4' '5' '6' '7' */ + '\060', '\061', '\062', '\063', '\064', '\065', '\066', '\067', + /* '8' '9' ':' ';' '<' '=' '>' '?' */ + '\070', '\071', '\072', '\073', '\074', '\075', '\076', '\077', + /* '@' 'A' 'B' 'C' 'D' 'E' 'F' 'G' */ + '\100', '\141', '\142', '\143', '\144', '\145', '\146', '\147', + /* 'H' 'I' 'J' 'K' 'L' 'M' 'N' 'O' */ + '\150', '\151', '\152', '\153', '\154', '\155', '\156', '\157', + /* 'P' 'Q' 'R' 'S' 'T' 'U' 'V' 'W' */ + '\160', '\161', '\162', '\163', '\164', '\165', '\166', '\167', + /* 'X' 'Y' 'Z' '[' '\' ']' '^' '_' */ + '\170', '\171', '\172', '\133', '\134', '\135', '\136', '\137', + /* '`' 'a' 'b' 'c' 'd' 'e' 'f' 'g' */ + '\140', '\141', '\142', '\143', '\144', '\145', '\146', '\147', + /* 'h' 'i' 'j' 'k' 'l' 'm' 'n' 'o' */ + '\150', '\151', '\152', '\153', '\154', '\155', '\156', '\157', + /* 'p' 'q' 'r' 's' 't' 'u' 'v' 'w' */ + '\160', '\161', '\162', '\163', '\164', '\165', '\166', '\167', + /* 'x' 'y' 'z' '{' '|' '}' '~' */ + '\170', '\171', '\172', '\173', '\174', '\175', '\176', '\177', + '\200', '\201', '\202', '\203', '\204', '\205', '\206', '\207', + '\210', '\211', '\212', '\213', '\214', '\215', '\216', '\217', + '\220', '\221', '\222', '\223', '\224', '\225', '\226', '\227', + '\230', '\231', '\232', '\233', '\234', '\235', '\236', '\237', + '\240', '\241', '\242', '\243', '\244', '\245', '\246', '\247', + '\250', '\251', '\252', '\253', '\254', '\255', '\256', '\257', + '\260', '\261', '\262', '\263', '\264', '\265', '\266', '\267', + '\270', '\271', '\272', '\273', '\274', '\275', '\276', '\277', + '\300', '\301', '\302', '\303', '\304', '\305', '\306', '\307', + '\310', '\311', '\312', '\313', '\314', '\315', '\316', '\317', + '\320', '\321', '\322', '\323', '\324', '\325', '\326', '\327', + '\330', '\331', '\332', '\333', '\334', '\335', '\336', '\337', + '\340', '\341', '\342', '\343', '\344', '\345', '\346', '\347', + '\350', '\351', '\352', '\353', '\354', '\355', '\356', '\357', + '\360', '\361', '\362', '\363', '\364', '\365', '\366', '\367', + '\370', '\371', '\372', '\373', '\374', '\375', '\376', '\377', +}; +#else +#include "You lose. You will need a translation table for your character set." +#endif + +/* + * Tree is a bunch of rules to run. Returns zero if it hit an exit() + * statement + */ +int +interpret(tree) +register NODE *volatile tree; +{ + jmp_buf volatile loop_tag_stack; /* shallow binding stack for loop_tag */ + static jmp_buf rule_tag; /* tag the rule currently being run, for NEXT + * and EXIT statements. It is static because + * there are no nested rules */ + register NODE *volatile t = NULL; /* temporary */ + NODE **volatile lhs; /* lhs == Left Hand Side for assigns, etc */ + NODE *volatile stable_tree; + int volatile traverse = 1; /* True => loop thru tree (Node_rule_list) */ + + if (tree == NULL) + return 1; + sourceline = tree->source_line; + source = tree->source_file; + switch (tree->type) { + case Node_rule_node: + traverse = 0; /* False => one for-loop iteration only */ + /* FALL THROUGH */ + case Node_rule_list: + for (t = tree; t != NULL; t = t->rnode) { + if (traverse) + tree = t->lnode; + sourceline = tree->source_line; + source = tree->source_file; + switch (setjmp(rule_tag)) { + case 0: /* normal non-jump */ + /* test pattern, if any */ + if (tree->lnode == NULL || + eval_condition(tree->lnode)) + (void) interpret(tree->rnode); + break; + case TAG_CONTINUE: /* NEXT statement */ + return 1; + case TAG_BREAK: + return 0; + default: + cant_happen(); + } + if (!traverse) /* case Node_rule_node */ + break; /* don't loop */ + } + break; + + case Node_statement_list: + for (t = tree; t != NULL; t = t->rnode) + (void) interpret(t->lnode); + break; + + case Node_K_if: + if (eval_condition(tree->lnode)) { + (void) interpret(tree->rnode->lnode); + } else { + (void) interpret(tree->rnode->rnode); + } + break; + + case Node_K_while: + PUSH_BINDING(loop_tag_stack, loop_tag, loop_tag_valid); + + stable_tree = tree; + while (eval_condition(stable_tree->lnode)) { + switch (setjmp(loop_tag)) { + case 0: /* normal non-jump */ + (void) interpret(stable_tree->rnode); + break; + case TAG_CONTINUE: /* continue statement */ + break; + case TAG_BREAK: /* break statement */ + RESTORE_BINDING(loop_tag_stack, loop_tag, loop_tag_valid); + return 1; + default: + cant_happen(); + } + } + RESTORE_BINDING(loop_tag_stack, loop_tag, loop_tag_valid); + break; + + case Node_K_do: + PUSH_BINDING(loop_tag_stack, loop_tag, loop_tag_valid); + stable_tree = tree; + do { + switch (setjmp(loop_tag)) { + case 0: /* normal non-jump */ + (void) interpret(stable_tree->rnode); + break; + case TAG_CONTINUE: /* continue statement */ + break; + case TAG_BREAK: /* break statement */ + RESTORE_BINDING(loop_tag_stack, loop_tag, loop_tag_valid); + return 1; + default: + cant_happen(); + } + } while (eval_condition(stable_tree->lnode)); + RESTORE_BINDING(loop_tag_stack, loop_tag, loop_tag_valid); + break; + + case Node_K_for: + PUSH_BINDING(loop_tag_stack, loop_tag, loop_tag_valid); + (void) interpret(tree->forloop->init); + stable_tree = tree; + while (eval_condition(stable_tree->forloop->cond)) { + switch (setjmp(loop_tag)) { + case 0: /* normal non-jump */ + (void) interpret(stable_tree->lnode); + /* fall through */ + case TAG_CONTINUE: /* continue statement */ + (void) interpret(stable_tree->forloop->incr); + break; + case TAG_BREAK: /* break statement */ + RESTORE_BINDING(loop_tag_stack, loop_tag, loop_tag_valid); + return 1; + default: + cant_happen(); + } + } + RESTORE_BINDING(loop_tag_stack, loop_tag, loop_tag_valid); + break; + + case Node_K_arrayfor: + { + volatile struct search l; /* For array_for */ + Func_ptr after_assign = NULL; + +#define hakvar forloop->init +#define arrvar forloop->incr + PUSH_BINDING(loop_tag_stack, loop_tag, loop_tag_valid); + lhs = get_lhs(tree->hakvar, &after_assign); + t = tree->arrvar; + if (t->type == Node_param_list) + t = stack_ptr[t->param_cnt]; + stable_tree = tree; + for (assoc_scan(t, (struct search *)&l); + l.retval; + assoc_next((struct search *)&l)) { + unref(*((NODE **) lhs)); + *lhs = dupnode(l.retval); + if (after_assign) + (*after_assign)(); + switch (setjmp(loop_tag)) { + case 0: + (void) interpret(stable_tree->lnode); + case TAG_CONTINUE: + break; + + case TAG_BREAK: + RESTORE_BINDING(loop_tag_stack, loop_tag, loop_tag_valid); + return 1; + default: + cant_happen(); + } + } + RESTORE_BINDING(loop_tag_stack, loop_tag, loop_tag_valid); + break; + } + + case Node_K_break: + if (loop_tag_valid == 0) + fatal("unexpected break"); + longjmp(loop_tag, TAG_BREAK); + break; + + case Node_K_continue: + if (loop_tag_valid == 0) { + /* + * AT&T nawk treats continue outside of loops like + * next. Allow it if not posix, and complain if + * lint. + */ + static int warned = 0; + + if (do_lint && ! warned) { + warning("use of `continue' outside of loop is not portable"); + warned = 1; + } + if (do_posix) + fatal("use of `continue' outside of loop is not allowed"); + longjmp(rule_tag, TAG_CONTINUE); + } else + longjmp(loop_tag, TAG_CONTINUE); + break; + + case Node_K_print: + do_print(tree); + break; + + case Node_K_printf: + do_printf(tree); + break; + + case Node_K_delete: + do_delete(tree->lnode, tree->rnode); + break; + + case Node_K_next: + longjmp(rule_tag, TAG_CONTINUE); + break; + + case Node_K_nextfile: + do_nextfile(); + break; + + case Node_K_exit: + /* + * In A,K,&W, p. 49, it says that an exit statement "... + * causes the program to behave as if the end of input had + * occurred; no more input is read, and the END actions, if + * any are executed." This implies that the rest of the rules + * are not done. So we immediately break out of the main loop. + */ + exiting = 1; + if (tree) { + t = tree_eval(tree->lnode); + exit_val = (int) force_number(t); + } + free_temp(t); + longjmp(rule_tag, TAG_BREAK); + break; + + case Node_K_return: + t = tree_eval(tree->lnode); + ret_node = dupnode(t); + free_temp(t); + longjmp(func_tag, TAG_RETURN); + break; + + default: + /* + * Appears to be an expression statement. Throw away the + * value. + */ + if (do_lint && tree->type == Node_var) + warning("statement has no effect"); + t = tree_eval(tree); + free_temp(t); + break; + } + return 1; +} + +/* evaluate a subtree */ + +NODE * +r_tree_eval(tree) +register NODE *tree; +{ + register NODE *r, *t1, *t2; /* return value & temporary subtrees */ + register NODE **lhs; + register int di; + AWKNUM x, x1, x2; + long lx; +#ifdef CRAY + long lx2; +#endif + +#ifdef DEBUG + if (tree == NULL) + return Nnull_string; + if (tree->type == Node_val) { + if (tree->stref <= 0) cant_happen(); + return tree; + } + if (tree->type == Node_var) { + if (tree->var_value->stref <= 0) cant_happen(); + return tree->var_value; + } + if (tree->type == Node_param_list) { + if (stack_ptr[tree->param_cnt] == NULL) + return Nnull_string; + else + return stack_ptr[tree->param_cnt]->var_value; + } +#endif + switch (tree->type) { + case Node_and: + return tmp_number((AWKNUM) (eval_condition(tree->lnode) + && eval_condition(tree->rnode))); + + case Node_or: + return tmp_number((AWKNUM) (eval_condition(tree->lnode) + || eval_condition(tree->rnode))); + + case Node_not: + return tmp_number((AWKNUM) ! eval_condition(tree->lnode)); + + /* Builtins */ + case Node_builtin: + return ((*tree->proc) (tree->subnode)); + + case Node_K_getline: + return (do_getline(tree)); + + case Node_in_array: + return tmp_number((AWKNUM) in_array(tree->lnode, tree->rnode)); + + case Node_func_call: + return func_call(tree->rnode, tree->lnode); + + /* unary operations */ + case Node_NR: + case Node_FNR: + case Node_NF: + case Node_FIELDWIDTHS: + case Node_FS: + case Node_RS: + case Node_field_spec: + case Node_subscript: + case Node_IGNORECASE: + case Node_OFS: + case Node_ORS: + case Node_OFMT: + case Node_CONVFMT: + lhs = get_lhs(tree, (Func_ptr *)0); + return *lhs; + + case Node_var_array: + fatal("attempt to use an array in a scalar context"); + + case Node_unary_minus: + t1 = tree_eval(tree->subnode); + x = -force_number(t1); + free_temp(t1); + return tmp_number(x); + + case Node_cond_exp: + if (eval_condition(tree->lnode)) + return tree_eval(tree->rnode->lnode); + return tree_eval(tree->rnode->rnode); + + case Node_match: + case Node_nomatch: + case Node_regex: + return match_op(tree); + + case Node_func: + fatal("function `%s' called with space between name and (,\n%s", + tree->lnode->param, + "or used in other expression context"); + + /* assignments */ + case Node_assign: + { + Func_ptr after_assign = NULL; + + r = tree_eval(tree->rnode); + lhs = get_lhs(tree->lnode, &after_assign); + if (r != *lhs) { + NODE *save; + + save = *lhs; + *lhs = dupnode(r); + unref(save); + } + free_temp(r); + if (after_assign) + (*after_assign)(); + return *lhs; + } + + case Node_concat: + { +#define STACKSIZE 10 + NODE *stack[STACKSIZE]; + register NODE **sp; + register int len; + char *str; + register char *dest; + + sp = stack; + len = 0; + while (tree->type == Node_concat) { + *sp = force_string(tree_eval(tree->lnode)); + tree = tree->rnode; + len += (*sp)->stlen; + if (++sp == &stack[STACKSIZE-2]) /* one more and NULL */ + break; + } + *sp = force_string(tree_eval(tree)); + len += (*sp)->stlen; + *++sp = NULL; + emalloc(str, char *, len+2, "tree_eval"); + dest = str; + sp = stack; + while (*sp) { + memcpy(dest, (*sp)->stptr, (*sp)->stlen); + dest += (*sp)->stlen; + free_temp(*sp); + sp++; + } + r = make_str_node(str, len, ALREADY_MALLOCED); + r->flags |= TEMP; + } + return r; + + /* other assignment types are easier because they are numeric */ + case Node_preincrement: + case Node_predecrement: + case Node_postincrement: + case Node_postdecrement: + case Node_assign_exp: + case Node_assign_times: + case Node_assign_quotient: + case Node_assign_mod: + case Node_assign_plus: + case Node_assign_minus: + return op_assign(tree); + default: + break; /* handled below */ + } + + /* evaluate subtrees in order to do binary operation, then keep going */ + t1 = tree_eval(tree->lnode); + t2 = tree_eval(tree->rnode); + + switch (tree->type) { + case Node_geq: + case Node_leq: + case Node_greater: + case Node_less: + case Node_notequal: + case Node_equal: + di = cmp_nodes(t1, t2); + free_temp(t1); + free_temp(t2); + switch (tree->type) { + case Node_equal: + return tmp_number((AWKNUM) (di == 0)); + case Node_notequal: + return tmp_number((AWKNUM) (di != 0)); + case Node_less: + return tmp_number((AWKNUM) (di < 0)); + case Node_greater: + return tmp_number((AWKNUM) (di > 0)); + case Node_leq: + return tmp_number((AWKNUM) (di <= 0)); + case Node_geq: + return tmp_number((AWKNUM) (di >= 0)); + default: + cant_happen(); + } + break; + default: + break; /* handled below */ + } + + x1 = force_number(t1); + free_temp(t1); + x2 = force_number(t2); + free_temp(t2); + switch (tree->type) { + case Node_exp: + if ((lx = x2) == x2 && lx >= 0) { /* integer exponent */ + if (lx == 0) + x = 1; + else if (lx == 1) + x = x1; + else { + /* doing it this way should be more precise */ + for (x = x1; --lx; ) + x *= x1; + } + } else + x = pow((double) x1, (double) x2); + return tmp_number(x); + + case Node_times: + return tmp_number(x1 * x2); + + case Node_quotient: + if (x2 == 0) + fatal("division by zero attempted"); +#ifdef _CRAY + /* + * special case for integer division, put in for Cray + */ + lx2 = x2; + if (lx2 == 0) + return tmp_number(x1 / x2); + lx = (long) x1 / lx2; + if (lx * x2 == x1) + return tmp_number((AWKNUM) lx); + else +#endif + return tmp_number(x1 / x2); + + case Node_mod: + if (x2 == 0) + fatal("division by zero attempted in mod"); +#ifndef FMOD_MISSING + return tmp_number(fmod (x1, x2)); +#else + (void) modf(x1 / x2, &x); + return tmp_number(x1 - x * x2); +#endif + + case Node_plus: + return tmp_number(x1 + x2); + + case Node_minus: + return tmp_number(x1 - x2); + + case Node_var_array: + fatal("attempt to use an array in a scalar context"); + + default: + fatal("illegal type (%d) in tree_eval", tree->type); + } + return 0; +} + +/* Is TREE true or false? Returns 0==false, non-zero==true */ +static int +eval_condition(tree) +register NODE *tree; +{ + register NODE *t1; + register int ret; + + if (tree == NULL) /* Null trees are the easiest kinds */ + return 1; + if (tree->type == Node_line_range) { + /* + * Node_line_range is kind of like Node_match, EXCEPT: the + * lnode field (more properly, the condpair field) is a node + * of a Node_cond_pair; whether we evaluate the lnode of that + * node or the rnode depends on the triggered word. More + * precisely: if we are not yet triggered, we tree_eval the + * lnode; if that returns true, we set the triggered word. + * If we are triggered (not ELSE IF, note), we tree_eval the + * rnode, clear triggered if it succeeds, and perform our + * action (regardless of success or failure). We want to be + * able to begin and end on a single input record, so this + * isn't an ELSE IF, as noted above. + */ + if (!tree->triggered) + if (!eval_condition(tree->condpair->lnode)) + return 0; + else + tree->triggered = 1; + /* Else we are triggered */ + if (eval_condition(tree->condpair->rnode)) + tree->triggered = 0; + return 1; + } + + /* + * Could just be J.random expression. in which case, null and 0 are + * false, anything else is true + */ + + t1 = tree_eval(tree); + if (t1->flags & MAYBE_NUM) + (void) force_number(t1); + if (t1->flags & NUMBER) + ret = t1->numbr != 0.0; + else + ret = t1->stlen != 0; + free_temp(t1); + return ret; +} + +/* + * compare two nodes, returning negative, 0, positive + */ +int +cmp_nodes(t1, t2) +register NODE *t1, *t2; +{ + register int ret; + register int len1, len2; + + if (t1 == t2) + return 0; + if (t1->flags & MAYBE_NUM) + (void) force_number(t1); + if (t2->flags & MAYBE_NUM) + (void) force_number(t2); + if ((t1->flags & NUMBER) && (t2->flags & NUMBER)) { + if (t1->numbr == t2->numbr) return 0; + else if (t1->numbr - t2->numbr < 0) return -1; + else return 1; + } + (void) force_string(t1); + (void) force_string(t2); + len1 = t1->stlen; + len2 = t2->stlen; + if (len1 == 0 || len2 == 0) + return len1 - len2; + ret = memcmp(t1->stptr, t2->stptr, len1 <= len2 ? len1 : len2); + return ret == 0 ? len1-len2 : ret; +} + +static NODE * +op_assign(tree) +register NODE *tree; +{ + AWKNUM rval, lval; + NODE **lhs; + AWKNUM t1, t2; + long ltemp; + NODE *tmp; + Func_ptr after_assign = NULL; + + lhs = get_lhs(tree->lnode, &after_assign); + lval = force_number(*lhs); + + /* + * Can't unref *lhs until we know the type; doing so + * too early breaks x += x sorts of things. + */ + switch(tree->type) { + case Node_preincrement: + case Node_predecrement: + unref(*lhs); + *lhs = make_number(lval + + (tree->type == Node_preincrement ? 1.0 : -1.0)); + if (after_assign) + (*after_assign)(); + return *lhs; + + case Node_postincrement: + case Node_postdecrement: + unref(*lhs); + *lhs = make_number(lval + + (tree->type == Node_postincrement ? 1.0 : -1.0)); + if (after_assign) + (*after_assign)(); + return tmp_number(lval); + default: + break; /* handled below */ + } + + tmp = tree_eval(tree->rnode); + rval = force_number(tmp); + free_temp(tmp); + unref(*lhs); + switch(tree->type) { + case Node_assign_exp: + if ((ltemp = rval) == rval) { /* integer exponent */ + if (ltemp == 0) + *lhs = make_number((AWKNUM) 1); + else if (ltemp == 1) + *lhs = make_number(lval); + else { + /* doing it this way should be more precise */ + for (t1 = t2 = lval; --ltemp; ) + t1 *= t2; + *lhs = make_number(t1); + } + } else + *lhs = make_number((AWKNUM) pow((double) lval, (double) rval)); + break; + + case Node_assign_times: + *lhs = make_number(lval * rval); + break; + + case Node_assign_quotient: + if (rval == (AWKNUM) 0) + fatal("division by zero attempted in /="); +#ifdef _CRAY + /* + * special case for integer division, put in for Cray + */ + ltemp = rval; + if (ltemp == 0) { + *lhs = make_number(lval / rval); + break; + } + ltemp = (long) lval / ltemp; + if (ltemp * lval == rval) + *lhs = make_number((AWKNUM) ltemp); + else +#endif + *lhs = make_number(lval / rval); + break; + + case Node_assign_mod: + if (rval == (AWKNUM) 0) + fatal("division by zero attempted in %="); +#ifndef FMOD_MISSING + *lhs = make_number(fmod(lval, rval)); +#else + (void) modf(lval / rval, &t1); + t2 = lval - rval * t1; + *lhs = make_number(t2); +#endif + break; + + case Node_assign_plus: + *lhs = make_number(lval + rval); + break; + + case Node_assign_minus: + *lhs = make_number(lval - rval); + break; + default: + cant_happen(); + } + if (after_assign) + (*after_assign)(); + return *lhs; +} + +NODE **stack_ptr; + +static NODE * +func_call(name, arg_list) +NODE *name; /* name is a Node_val giving function name */ +NODE *arg_list; /* Node_expression_list of calling args. */ +{ + register NODE *arg, *argp, *r; + NODE *n, *f; + jmp_buf volatile func_tag_stack; + jmp_buf volatile loop_tag_stack; + int volatile save_loop_tag_valid = 0; + NODE **volatile save_stack, *save_ret_node; + NODE **volatile local_stack = NULL, **sp; + int count; + extern NODE *ret_node; + + /* + * retrieve function definition node + */ + f = lookup(name->stptr); + if (!f || f->type != Node_func) + fatal("function `%s' not defined", name->stptr); +#ifdef FUNC_TRACE + fprintf(stderr, "function %s called\n", name->stptr); +#endif + count = f->lnode->param_cnt; + if (count) + emalloc(local_stack, NODE **, count*sizeof(NODE *), "func_call"); + sp = local_stack; + + /* + * for each calling arg. add NODE * on stack + */ + for (argp = arg_list; count && argp != NULL; argp = argp->rnode) { + arg = argp->lnode; + getnode(r); + r->type = Node_var; + /* + * call by reference for arrays; see below also + */ + if (arg->type == Node_param_list) + arg = stack_ptr[arg->param_cnt]; + if (arg->type == Node_var_array) + *r = *arg; + else { + n = tree_eval(arg); + r->lnode = dupnode(n); + r->rnode = (NODE *) NULL; + free_temp(n); + } + *sp++ = r; + count--; + } + if (argp != NULL) /* left over calling args. */ + warning( + "function `%s' called with more arguments than declared", + name->stptr); + /* + * add remaining params. on stack with null value + */ + while (count-- > 0) { + getnode(r); + r->type = Node_var; + r->lnode = Nnull_string; + r->rnode = (NODE *) NULL; + *sp++ = r; + } + + /* + * Execute function body, saving context, as a return statement + * will longjmp back here. + * + * Have to save and restore the loop_tag stuff so that a return + * inside a loop in a function body doesn't scrog any loops going + * on in the main program. We save the necessary info in variables + * local to this function so that function nesting works OK. + * We also only bother to save the loop stuff if we're in a loop + * when the function is called. + */ + if (loop_tag_valid) { + int junk = 0; + + save_loop_tag_valid = (volatile int) loop_tag_valid; + PUSH_BINDING(loop_tag_stack, loop_tag, junk); + loop_tag_valid = 0; + } + save_stack = stack_ptr; + stack_ptr = local_stack; + PUSH_BINDING(func_tag_stack, func_tag, func_tag_valid); + save_ret_node = ret_node; + ret_node = Nnull_string; /* default return value */ + if (setjmp(func_tag) == 0) + (void) interpret(f->rnode); + + r = ret_node; + ret_node = (NODE *) save_ret_node; + RESTORE_BINDING(func_tag_stack, func_tag, func_tag_valid); + stack_ptr = (NODE **) save_stack; + + /* + * here, we pop each parameter and check whether + * it was an array. If so, and if the arg. passed in was + * a simple variable, then the value should be copied back. + * This achieves "call-by-reference" for arrays. + */ + sp = local_stack; + count = f->lnode->param_cnt; + for (argp = arg_list; count > 0 && argp != NULL; argp = argp->rnode) { + arg = argp->lnode; + if (arg->type == Node_param_list) + arg = stack_ptr[arg->param_cnt]; + n = *sp++; + if (arg->type == Node_var && n->type == Node_var_array) { + /* should we free arg->var_value ? */ + arg->var_array = n->var_array; + arg->type = Node_var_array; + } + unref(n->lnode); + freenode(n); + count--; + } + while (count-- > 0) { + n = *sp++; + /* if n is an (local) array, all the elements should be freed */ + if (n->type == Node_var_array) { + assoc_clear(n); + free(n->var_array); + } + unref(n->lnode); + freenode(n); + } + if (local_stack) + free((char *) local_stack); + + /* Restore the loop_tag stuff if necessary. */ + if (save_loop_tag_valid) { + int junk = 0; + + loop_tag_valid = (int) save_loop_tag_valid; + RESTORE_BINDING(loop_tag_stack, loop_tag, junk); + } + + if (!(r->flags & PERM)) + r->flags |= TEMP; + return r; +} + +/* + * This returns a POINTER to a node pointer. get_lhs(ptr) is the current + * value of the var, or where to store the var's new value + */ + +NODE ** +get_lhs(ptr, assign) +register NODE *ptr; +Func_ptr *assign; +{ + register NODE **aptr = NULL; + register NODE *n; + + switch (ptr->type) { + case Node_var_array: + fatal("attempt to use an array in a scalar context"); + case Node_var: + aptr = &(ptr->var_value); +#ifdef DEBUG + if (ptr->var_value->stref <= 0) + cant_happen(); +#endif + break; + + case Node_FIELDWIDTHS: + aptr = &(FIELDWIDTHS_node->var_value); + if (assign) + *assign = set_FIELDWIDTHS; + break; + + case Node_RS: + aptr = &(RS_node->var_value); + if (assign) + *assign = set_RS; + break; + + case Node_FS: + aptr = &(FS_node->var_value); + if (assign) + *assign = set_FS; + break; + + case Node_FNR: + unref(FNR_node->var_value); + FNR_node->var_value = make_number((AWKNUM) FNR); + aptr = &(FNR_node->var_value); + if (assign) + *assign = set_FNR; + break; + + case Node_NR: + unref(NR_node->var_value); + NR_node->var_value = make_number((AWKNUM) NR); + aptr = &(NR_node->var_value); + if (assign) + *assign = set_NR; + break; + + case Node_NF: + if (NF == -1) + (void) get_field(HUGE-1, assign); /* parse record */ + unref(NF_node->var_value); + NF_node->var_value = make_number((AWKNUM) NF); + aptr = &(NF_node->var_value); + if (assign) + *assign = set_NF; + break; + + case Node_IGNORECASE: + unref(IGNORECASE_node->var_value); + IGNORECASE_node->var_value = make_number((AWKNUM) IGNORECASE); + aptr = &(IGNORECASE_node->var_value); + if (assign) + *assign = set_IGNORECASE; + break; + + case Node_OFMT: + aptr = &(OFMT_node->var_value); + if (assign) + *assign = set_OFMT; + break; + + case Node_CONVFMT: + aptr = &(CONVFMT_node->var_value); + if (assign) + *assign = set_CONVFMT; + break; + + case Node_ORS: + aptr = &(ORS_node->var_value); + if (assign) + *assign = set_ORS; + break; + + case Node_OFS: + aptr = &(OFS_node->var_value); + if (assign) + *assign = set_OFS; + break; + + case Node_param_list: + aptr = &(stack_ptr[ptr->param_cnt]->var_value); + break; + + case Node_field_spec: + { + int field_num; + + n = tree_eval(ptr->lnode); + field_num = (int) force_number(n); + free_temp(n); + if (field_num < 0) + fatal("attempt to access field %d", field_num); + if (field_num == 0 && field0_valid) { /* short circuit */ + aptr = &fields_arr[0]; + if (assign) + *assign = reset_record; + break; + } + aptr = get_field(field_num, assign); + break; + } + case Node_subscript: + n = ptr->lnode; + if (n->type == Node_param_list) + n = stack_ptr[n->param_cnt]; + aptr = assoc_lookup(n, concat_exp(ptr->rnode)); + break; + + case Node_func: + fatal ("`%s' is a function, assignment is not allowed", + ptr->lnode->param); + default: + cant_happen(); + } + return aptr; +} + +static NODE * +match_op(tree) +register NODE *tree; +{ + register NODE *t1; + register Regexp *rp; + int i; + int match = 1; + + if (tree->type == Node_nomatch) + match = 0; + if (tree->type == Node_regex) + t1 = *get_field(0, (Func_ptr *) 0); + else { + t1 = force_string(tree_eval(tree->lnode)); + tree = tree->rnode; + } + rp = re_update(tree); + i = research(rp, t1->stptr, 0, t1->stlen, 0); + i = (i == -1) ^ (match == 1); + free_temp(t1); + return tmp_number((AWKNUM) i); +} + +void +set_IGNORECASE() +{ + static int warned = 0; + + if ((do_lint || do_unix) && ! warned) { + warned = 1; + warning("IGNORECASE not supported in compatibility mode"); + } + IGNORECASE = (force_number(IGNORECASE_node->var_value) != 0.0); + set_FS(); +} + +void +set_OFS() +{ + OFS = force_string(OFS_node->var_value)->stptr; + OFSlen = OFS_node->var_value->stlen; + OFS[OFSlen] = '\0'; +} + +void +set_ORS() +{ + ORS = force_string(ORS_node->var_value)->stptr; + ORSlen = ORS_node->var_value->stlen; + ORS[ORSlen] = '\0'; +} + +static NODE **fmt_list = NULL; +static int fmt_ok P((NODE *n)); +static int fmt_index P((NODE *n)); + +static int +fmt_ok(n) +NODE *n; +{ + /* to be done later */ + return 1; +} + +static int +fmt_index(n) +NODE *n; +{ + register int ix = 0; + static int fmt_num = 4; + static int fmt_hiwater = 0; + + if (fmt_list == NULL) + emalloc(fmt_list, NODE **, fmt_num*sizeof(*fmt_list), "fmt_index"); + (void) force_string(n); + while (ix < fmt_hiwater) { + if (cmp_nodes(fmt_list[ix], n) == 0) + return ix; + ix++; + } + /* not found */ + n->stptr[n->stlen] = '\0'; + if (!fmt_ok(n)) + warning("bad FMT specification"); + if (fmt_hiwater >= fmt_num) { + fmt_num *= 2; + emalloc(fmt_list, NODE **, fmt_num, "fmt_index"); + } + fmt_list[fmt_hiwater] = dupnode(n); + return fmt_hiwater++; +} + +void +set_OFMT() +{ + OFMTidx = fmt_index(OFMT_node->var_value); + OFMT = fmt_list[OFMTidx]->stptr; +} + +void +set_CONVFMT() +{ + CONVFMTidx = fmt_index(CONVFMT_node->var_value); + CONVFMT = fmt_list[CONVFMTidx]->stptr; +} |
