4.4BSD/usr/src/contrib/gawk-2.15.2/eval.c
/*
* 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;
}