4.4BSD/usr/src/contrib/gawk-2.15.2/awk.y
/*
* awk.y --- yacc/bison parser
*/
/*
* 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.
*/
%{
#ifdef DEBUG
#define YYDEBUG 12
#endif
#include "awk.h"
static void yyerror (); /* va_alist */
static char *get_src_buf P((void));
static int yylex P((void));
static NODE *node_common P((NODETYPE op));
static NODE *snode P((NODE *subn, NODETYPE op, int sindex));
static NODE *mkrangenode P((NODE *cpair));
static NODE *make_for_loop P((NODE *init, NODE *cond, NODE *incr));
static NODE *append_right P((NODE *list, NODE *new));
static void func_install P((NODE *params, NODE *def));
static void pop_var P((NODE *np, int freeit));
static void pop_params P((NODE *params));
static NODE *make_param P((char *name));
static NODE *mk_rexp P((NODE *exp));
static int want_assign; /* lexical scanning kludge */
static int want_regexp; /* lexical scanning kludge */
static int can_return; /* lexical scanning kludge */
static int io_allowed = 1; /* lexical scanning kludge */
static char *lexptr; /* pointer to next char during parsing */
static char *lexend;
static char *lexptr_begin; /* keep track of where we were for error msgs */
static char *lexeme; /* beginning of lexeme for debugging */
static char *thisline = NULL;
#define YYDEBUG_LEXER_TEXT (lexeme)
static int param_counter;
static char *tokstart = NULL;
static char *token = NULL;
static char *tokend;
NODE *variables[HASHSIZE];
extern char *source;
extern int sourceline;
extern struct src *srcfiles;
extern int numfiles;
extern int errcount;
extern NODE *begin_block;
extern NODE *end_block;
%}
%union {
long lval;
AWKNUM fval;
NODE *nodeval;
NODETYPE nodetypeval;
char *sval;
NODE *(*ptrval)();
}
%type <nodeval> function_prologue function_body
%type <nodeval> rexp exp start program rule simp_exp
%type <nodeval> non_post_simp_exp
%type <nodeval> pattern
%type <nodeval> action variable param_list
%type <nodeval> rexpression_list opt_rexpression_list
%type <nodeval> expression_list opt_expression_list
%type <nodeval> statements statement if_statement opt_param_list
%type <nodeval> opt_exp opt_variable regexp
%type <nodeval> input_redir output_redir
%type <nodetypeval> print
%type <sval> func_name
%type <lval> lex_builtin
%token <sval> FUNC_CALL NAME REGEXP
%token <lval> ERROR
%token <nodeval> YNUMBER YSTRING
%token <nodetypeval> RELOP APPEND_OP
%token <nodetypeval> ASSIGNOP MATCHOP NEWLINE CONCAT_OP
%token <nodetypeval> LEX_BEGIN LEX_END LEX_IF LEX_ELSE LEX_RETURN LEX_DELETE
%token <nodetypeval> LEX_WHILE LEX_DO LEX_FOR LEX_BREAK LEX_CONTINUE
%token <nodetypeval> LEX_PRINT LEX_PRINTF LEX_NEXT LEX_EXIT LEX_FUNCTION
%token <nodetypeval> LEX_GETLINE
%token <nodetypeval> LEX_IN
%token <lval> LEX_AND LEX_OR INCREMENT DECREMENT
%token <lval> LEX_BUILTIN LEX_LENGTH
/* these are just yylval numbers */
/* Lowest to highest */
%right ASSIGNOP
%right '?' ':'
%left LEX_OR
%left LEX_AND
%left LEX_GETLINE
%nonassoc LEX_IN
%left FUNC_CALL LEX_BUILTIN LEX_LENGTH
%nonassoc MATCHOP
%nonassoc RELOP '<' '>' '|' APPEND_OP
%left CONCAT_OP
%left YSTRING YNUMBER
%left '+' '-'
%left '*' '/' '%'
%right '!' UNARY
%right '^'
%left INCREMENT DECREMENT
%left '$'
%left '(' ')'
%%
start
: opt_nls program opt_nls
{ expression_value = $2; }
;
program
: rule
{
if ($1 != NULL)
$$ = $1;
else
$$ = NULL;
yyerrok;
}
| program rule
/* add the rule to the tail of list */
{
if ($2 == NULL)
$$ = $1;
else if ($1 == NULL)
$$ = $2;
else {
if ($1->type != Node_rule_list)
$1 = node($1, Node_rule_list,
(NODE*)NULL);
$$ = append_right ($1,
node($2, Node_rule_list,(NODE *) NULL));
}
yyerrok;
}
| error { $$ = NULL; }
| program error { $$ = NULL; }
;
rule
: LEX_BEGIN { io_allowed = 0; }
action
{
if (begin_block) {
if (begin_block->type != Node_rule_list)
begin_block = node(begin_block, Node_rule_list,
(NODE *)NULL);
(void) append_right (begin_block, node(
node((NODE *)NULL, Node_rule_node, $3),
Node_rule_list, (NODE *)NULL) );
} else
begin_block = node((NODE *)NULL, Node_rule_node, $3);
$$ = NULL;
io_allowed = 1;
yyerrok;
}
| LEX_END { io_allowed = 0; }
action
{
if (end_block) {
if (end_block->type != Node_rule_list)
end_block = node(end_block, Node_rule_list,
(NODE *)NULL);
(void) append_right (end_block, node(
node((NODE *)NULL, Node_rule_node, $3),
Node_rule_list, (NODE *)NULL));
} else
end_block = node((NODE *)NULL, Node_rule_node, $3);
$$ = NULL;
io_allowed = 1;
yyerrok;
}
| LEX_BEGIN statement_term
{
warning("BEGIN blocks must have an action part");
errcount++;
yyerrok;
}
| LEX_END statement_term
{
warning("END blocks must have an action part");
errcount++;
yyerrok;
}
| pattern action
{ $$ = node ($1, Node_rule_node, $2); yyerrok; }
| action
{ $$ = node ((NODE *)NULL, Node_rule_node, $1); yyerrok; }
| pattern statement_term
{
$$ = node ($1,
Node_rule_node,
node(node(node(make_number(0.0),
Node_field_spec,
(NODE *) NULL),
Node_expression_list,
(NODE *) NULL),
Node_K_print,
(NODE *) NULL));
yyerrok;
}
| function_prologue function_body
{
func_install($1, $2);
$$ = NULL;
yyerrok;
}
;
func_name
: NAME
{ $$ = $1; }
| FUNC_CALL
{ $$ = $1; }
| lex_builtin
{
yyerror("%s() is a built-in function, it cannot be redefined",
tokstart);
errcount++;
/* yyerrok; */
}
;
lex_builtin
: LEX_BUILTIN
| LEX_LENGTH
;
function_prologue
: LEX_FUNCTION
{
param_counter = 0;
}
func_name '(' opt_param_list r_paren opt_nls
{
$$ = append_right(make_param($3), $5);
can_return = 1;
}
;
function_body
: l_brace statements r_brace opt_semi
{
$$ = $2;
can_return = 0;
}
;
pattern
: exp
{ $$ = $1; }
| exp comma exp
{ $$ = mkrangenode ( node($1, Node_cond_pair, $3) ); }
;
regexp
/*
* In this rule, want_regexp tells yylex that the next thing
* is a regexp so it should read up to the closing slash.
*/
: '/'
{ ++want_regexp; }
REGEXP '/'
{
NODE *n;
int len;
getnode(n);
n->type = Node_regex;
len = strlen($3);
n->re_exp = make_string($3, len);
n->re_reg = make_regexp($3, len, 0, 1);
n->re_text = NULL;
n->re_flags = CONST;
n->re_cnt = 1;
$$ = n;
}
;
action
: l_brace statements r_brace opt_semi opt_nls
{ $$ = $2 ; }
| l_brace r_brace opt_semi opt_nls
{ $$ = NULL; }
;
statements
: statement
{ $$ = $1; }
| statements statement
{
if ($1 == NULL || $1->type != Node_statement_list)
$1 = node($1, Node_statement_list,(NODE *)NULL);
$$ = append_right($1,
node( $2, Node_statement_list, (NODE *)NULL));
yyerrok;
}
| error
{ $$ = NULL; }
| statements error
{ $$ = NULL; }
;
statement_term
: nls
| semi opt_nls
;
statement
: semi opt_nls
{ $$ = NULL; }
| l_brace r_brace
{ $$ = NULL; }
| l_brace statements r_brace
{ $$ = $2; }
| if_statement
{ $$ = $1; }
| LEX_WHILE '(' exp r_paren opt_nls statement
{ $$ = node ($3, Node_K_while, $6); }
| LEX_DO opt_nls statement LEX_WHILE '(' exp r_paren opt_nls
{ $$ = node ($6, Node_K_do, $3); }
| LEX_FOR '(' NAME LEX_IN NAME r_paren opt_nls statement
{
$$ = node ($8, Node_K_arrayfor, make_for_loop(variable($3,1),
(NODE *)NULL, variable($5,1)));
}
| LEX_FOR '(' opt_exp semi exp semi opt_exp r_paren opt_nls statement
{
$$ = node($10, Node_K_for, (NODE *)make_for_loop($3, $5, $7));
}
| LEX_FOR '(' opt_exp semi semi opt_exp r_paren opt_nls statement
{
$$ = node ($9, Node_K_for,
(NODE *)make_for_loop($3, (NODE *)NULL, $6));
}
| LEX_BREAK statement_term
/* for break, maybe we'll have to remember where to break to */
{ $$ = node ((NODE *)NULL, Node_K_break, (NODE *)NULL); }
| LEX_CONTINUE statement_term
/* similarly */
{ $$ = node ((NODE *)NULL, Node_K_continue, (NODE *)NULL); }
| print '(' expression_list r_paren output_redir statement_term
{ $$ = node ($3, $1, $5); }
| print opt_rexpression_list output_redir statement_term
{
if ($1 == Node_K_print && $2 == NULL)
$2 = node(node(make_number(0.0),
Node_field_spec,
(NODE *) NULL),
Node_expression_list,
(NODE *) NULL);
$$ = node ($2, $1, $3);
}
| LEX_NEXT opt_exp statement_term
{ NODETYPE type;
if ($2 && $2 == lookup("file")) {
if (do_lint)
warning("`next file' is a gawk extension");
else if (do_unix || do_posix)
yyerror("`next file' is a gawk extension");
else if (! io_allowed)
yyerror("`next file' used in BEGIN or END action");
type = Node_K_nextfile;
} else {
if (! io_allowed)
yyerror("next used in BEGIN or END action");
type = Node_K_next;
}
$$ = node ((NODE *)NULL, type, (NODE *)NULL);
}
| LEX_EXIT opt_exp statement_term
{ $$ = node ($2, Node_K_exit, (NODE *)NULL); }
| LEX_RETURN
{ if (! can_return) yyerror("return used outside function context"); }
opt_exp statement_term
{ $$ = node ($3, Node_K_return, (NODE *)NULL); }
| LEX_DELETE NAME '[' expression_list ']' statement_term
{ $$ = node (variable($2,1), Node_K_delete, $4); }
| exp statement_term
{ $$ = $1; }
;
print
: LEX_PRINT
{ $$ = $1; }
| LEX_PRINTF
{ $$ = $1; }
;
if_statement
: LEX_IF '(' exp r_paren opt_nls statement
{
$$ = node($3, Node_K_if,
node($6, Node_if_branches, (NODE *)NULL));
}
| LEX_IF '(' exp r_paren opt_nls statement
LEX_ELSE opt_nls statement
{ $$ = node ($3, Node_K_if,
node ($6, Node_if_branches, $9)); }
;
nls
: NEWLINE
{ want_assign = 0; }
| nls NEWLINE
;
opt_nls
: /* empty */
| nls
;
input_redir
: /* empty */
{ $$ = NULL; }
| '<' simp_exp
{ $$ = node ($2, Node_redirect_input, (NODE *)NULL); }
;
output_redir
: /* empty */
{ $$ = NULL; }
| '>' exp
{ $$ = node ($2, Node_redirect_output, (NODE *)NULL); }
| APPEND_OP exp
{ $$ = node ($2, Node_redirect_append, (NODE *)NULL); }
| '|' exp
{ $$ = node ($2, Node_redirect_pipe, (NODE *)NULL); }
;
opt_param_list
: /* empty */
{ $$ = NULL; }
| param_list
{ $$ = $1; }
;
param_list
: NAME
{ $$ = make_param($1); }
| param_list comma NAME
{ $$ = append_right($1, make_param($3)); yyerrok; }
| error
{ $$ = NULL; }
| param_list error
{ $$ = NULL; }
| param_list comma error
{ $$ = NULL; }
;
/* optional expression, as in for loop */
opt_exp
: /* empty */
{ $$ = NULL; }
| exp
{ $$ = $1; }
;
opt_rexpression_list
: /* empty */
{ $$ = NULL; }
| rexpression_list
{ $$ = $1; }
;
rexpression_list
: rexp
{ $$ = node ($1, Node_expression_list, (NODE *)NULL); }
| rexpression_list comma rexp
{
$$ = append_right($1,
node( $3, Node_expression_list, (NODE *)NULL));
yyerrok;
}
| error
{ $$ = NULL; }
| rexpression_list error
{ $$ = NULL; }
| rexpression_list error rexp
{ $$ = NULL; }
| rexpression_list comma error
{ $$ = NULL; }
;
opt_expression_list
: /* empty */
{ $$ = NULL; }
| expression_list
{ $$ = $1; }
;
expression_list
: exp
{ $$ = node ($1, Node_expression_list, (NODE *)NULL); }
| expression_list comma exp
{
$$ = append_right($1,
node( $3, Node_expression_list, (NODE *)NULL));
yyerrok;
}
| error
{ $$ = NULL; }
| expression_list error
{ $$ = NULL; }
| expression_list error exp
{ $$ = NULL; }
| expression_list comma error
{ $$ = NULL; }
;
/* Expressions, not including the comma operator. */
exp : variable ASSIGNOP
{ want_assign = 0; }
exp
{
if (do_lint && $4->type == Node_regex)
warning("Regular expression on left of assignment.");
$$ = node ($1, $2, $4);
}
| '(' expression_list r_paren LEX_IN NAME
{ $$ = node (variable($5,1), Node_in_array, $2); }
| exp '|' LEX_GETLINE opt_variable
{
$$ = node ($4, Node_K_getline,
node ($1, Node_redirect_pipein, (NODE *)NULL));
}
| LEX_GETLINE opt_variable input_redir
{
if (do_lint && ! io_allowed && $3 == NULL)
warning("non-redirected getline undefined inside BEGIN or END action");
$$ = node ($2, Node_K_getline, $3);
}
| exp LEX_AND exp
{ $$ = node ($1, Node_and, $3); }
| exp LEX_OR exp
{ $$ = node ($1, Node_or, $3); }
| exp MATCHOP exp
{
if ($1->type == Node_regex)
warning("Regular expression on left of MATCH operator.");
$$ = node ($1, $2, mk_rexp($3));
}
| regexp
{ $$ = $1; }
| '!' regexp %prec UNARY
{
$$ = node(node(make_number(0.0),
Node_field_spec,
(NODE *) NULL),
Node_nomatch,
$2);
}
| exp LEX_IN NAME
{ $$ = node (variable($3,1), Node_in_array, $1); }
| exp RELOP exp
{
if (do_lint && $3->type == Node_regex)
warning("Regular expression on left of comparison.");
$$ = node ($1, $2, $3);
}
| exp '<' exp
{ $$ = node ($1, Node_less, $3); }
| exp '>' exp
{ $$ = node ($1, Node_greater, $3); }
| exp '?' exp ':' exp
{ $$ = node($1, Node_cond_exp, node($3, Node_if_branches, $5));}
| simp_exp
{ $$ = $1; }
| exp simp_exp %prec CONCAT_OP
{ $$ = node ($1, Node_concat, $2); }
;
rexp
: variable ASSIGNOP
{ want_assign = 0; }
rexp
{ $$ = node ($1, $2, $4); }
| rexp LEX_AND rexp
{ $$ = node ($1, Node_and, $3); }
| rexp LEX_OR rexp
{ $$ = node ($1, Node_or, $3); }
| LEX_GETLINE opt_variable input_redir
{
if (do_lint && ! io_allowed && $3 == NULL)
warning("non-redirected getline undefined inside BEGIN or END action");
$$ = node ($2, Node_K_getline, $3);
}
| regexp
{ $$ = $1; }
| '!' regexp %prec UNARY
{ $$ = node((NODE *) NULL, Node_nomatch, $2); }
| rexp MATCHOP rexp
{ $$ = node ($1, $2, mk_rexp($3)); }
| rexp LEX_IN NAME
{ $$ = node (variable($3,1), Node_in_array, $1); }
| rexp RELOP rexp
{ $$ = node ($1, $2, $3); }
| rexp '?' rexp ':' rexp
{ $$ = node($1, Node_cond_exp, node($3, Node_if_branches, $5));}
| simp_exp
{ $$ = $1; }
| rexp simp_exp %prec CONCAT_OP
{ $$ = node ($1, Node_concat, $2); }
;
simp_exp
: non_post_simp_exp
/* Binary operators in order of decreasing precedence. */
| simp_exp '^' simp_exp
{ $$ = node ($1, Node_exp, $3); }
| simp_exp '*' simp_exp
{ $$ = node ($1, Node_times, $3); }
| simp_exp '/' simp_exp
{ $$ = node ($1, Node_quotient, $3); }
| simp_exp '%' simp_exp
{ $$ = node ($1, Node_mod, $3); }
| simp_exp '+' simp_exp
{ $$ = node ($1, Node_plus, $3); }
| simp_exp '-' simp_exp
{ $$ = node ($1, Node_minus, $3); }
| variable INCREMENT
{ $$ = node ($1, Node_postincrement, (NODE *)NULL); }
| variable DECREMENT
{ $$ = node ($1, Node_postdecrement, (NODE *)NULL); }
;
non_post_simp_exp
: '!' simp_exp %prec UNARY
{ $$ = node ($2, Node_not,(NODE *) NULL); }
| '(' exp r_paren
{ $$ = $2; }
| LEX_BUILTIN
'(' opt_expression_list r_paren
{ $$ = snode ($3, Node_builtin, (int) $1); }
| LEX_LENGTH '(' opt_expression_list r_paren
{ $$ = snode ($3, Node_builtin, (int) $1); }
| LEX_LENGTH
{
if (do_lint)
warning("call of `length' without parentheses is not portable");
$$ = snode ((NODE *)NULL, Node_builtin, (int) $1);
if (do_posix)
warning( "call of `length' without parentheses is deprecated by POSIX");
}
| FUNC_CALL '(' opt_expression_list r_paren
{
$$ = node ($3, Node_func_call, make_string($1, strlen($1)));
}
| variable
| INCREMENT variable
{ $$ = node ($2, Node_preincrement, (NODE *)NULL); }
| DECREMENT variable
{ $$ = node ($2, Node_predecrement, (NODE *)NULL); }
| YNUMBER
{ $$ = $1; }
| YSTRING
{ $$ = $1; }
| '-' simp_exp %prec UNARY
{ if ($2->type == Node_val) {
$2->numbr = -(force_number($2));
$$ = $2;
} else
$$ = node ($2, Node_unary_minus, (NODE *)NULL);
}
| '+' simp_exp %prec UNARY
{ $$ = $2; }
;
opt_variable
: /* empty */
{ $$ = NULL; }
| variable
{ $$ = $1; }
;
variable
: NAME
{ $$ = variable($1,1); }
| NAME '[' expression_list ']'
{
if ($3->rnode == NULL) {
$$ = node (variable($1,1), Node_subscript, $3->lnode);
freenode($3);
} else
$$ = node (variable($1,1), Node_subscript, $3);
}
| '$' non_post_simp_exp
{ $$ = node ($2, Node_field_spec, (NODE *)NULL); }
;
l_brace
: '{' opt_nls
;
r_brace
: '}' opt_nls { yyerrok; }
;
r_paren
: ')' { yyerrok; }
;
opt_semi
: /* empty */
| semi
;
semi
: ';' { yyerrok; want_assign = 0; }
;
comma : ',' opt_nls { yyerrok; }
;
%%
struct token {
char *operator; /* text to match */
NODETYPE value; /* node type */
int class; /* lexical class */
unsigned flags; /* # of args. allowed and compatability */
# define ARGS 0xFF /* 0, 1, 2, 3 args allowed (any combination */
# define A(n) (1<<(n))
# define VERSION 0xFF00 /* old awk is zero */
# define NOT_OLD 0x0100 /* feature not in old awk */
# define NOT_POSIX 0x0200 /* feature not in POSIX */
# define GAWKX 0x0400 /* gawk extension */
NODE *(*ptr) (); /* function that implements this keyword */
};
extern NODE
*do_exp(), *do_getline(), *do_index(), *do_length(),
*do_sqrt(), *do_log(), *do_sprintf(), *do_substr(),
*do_split(), *do_system(), *do_int(), *do_close(),
*do_atan2(), *do_sin(), *do_cos(), *do_rand(),
*do_srand(), *do_match(), *do_tolower(), *do_toupper(),
*do_sub(), *do_gsub(), *do_strftime(), *do_systime();
/* Tokentab is sorted ascii ascending order, so it can be binary searched. */
static struct token tokentab[] = {
{"BEGIN", Node_illegal, LEX_BEGIN, 0, 0},
{"END", Node_illegal, LEX_END, 0, 0},
{"atan2", Node_builtin, LEX_BUILTIN, NOT_OLD|A(2), do_atan2},
{"break", Node_K_break, LEX_BREAK, 0, 0},
{"close", Node_builtin, LEX_BUILTIN, NOT_OLD|A(1), do_close},
{"continue", Node_K_continue, LEX_CONTINUE, 0, 0},
{"cos", Node_builtin, LEX_BUILTIN, NOT_OLD|A(1), do_cos},
{"delete", Node_K_delete, LEX_DELETE, NOT_OLD, 0},
{"do", Node_K_do, LEX_DO, NOT_OLD, 0},
{"else", Node_illegal, LEX_ELSE, 0, 0},
{"exit", Node_K_exit, LEX_EXIT, 0, 0},
{"exp", Node_builtin, LEX_BUILTIN, A(1), do_exp},
{"for", Node_K_for, LEX_FOR, 0, 0},
{"func", Node_K_function, LEX_FUNCTION, NOT_POSIX|NOT_OLD, 0},
{"function", Node_K_function, LEX_FUNCTION, NOT_OLD, 0},
{"getline", Node_K_getline, LEX_GETLINE, NOT_OLD, 0},
{"gsub", Node_builtin, LEX_BUILTIN, NOT_OLD|A(2)|A(3), do_gsub},
{"if", Node_K_if, LEX_IF, 0, 0},
{"in", Node_illegal, LEX_IN, 0, 0},
{"index", Node_builtin, LEX_BUILTIN, A(2), do_index},
{"int", Node_builtin, LEX_BUILTIN, A(1), do_int},
{"length", Node_builtin, LEX_LENGTH, A(0)|A(1), do_length},
{"log", Node_builtin, LEX_BUILTIN, A(1), do_log},
{"match", Node_builtin, LEX_BUILTIN, NOT_OLD|A(2), do_match},
{"next", Node_K_next, LEX_NEXT, 0, 0},
{"print", Node_K_print, LEX_PRINT, 0, 0},
{"printf", Node_K_printf, LEX_PRINTF, 0, 0},
{"rand", Node_builtin, LEX_BUILTIN, NOT_OLD|A(0), do_rand},
{"return", Node_K_return, LEX_RETURN, NOT_OLD, 0},
{"sin", Node_builtin, LEX_BUILTIN, NOT_OLD|A(1), do_sin},
{"split", Node_builtin, LEX_BUILTIN, A(2)|A(3), do_split},
{"sprintf", Node_builtin, LEX_BUILTIN, 0, do_sprintf},
{"sqrt", Node_builtin, LEX_BUILTIN, A(1), do_sqrt},
{"srand", Node_builtin, LEX_BUILTIN, NOT_OLD|A(0)|A(1), do_srand},
{"strftime", Node_builtin, LEX_BUILTIN, GAWKX|A(1)|A(2), do_strftime},
{"sub", Node_builtin, LEX_BUILTIN, NOT_OLD|A(2)|A(3), do_sub},
{"substr", Node_builtin, LEX_BUILTIN, A(2)|A(3), do_substr},
{"system", Node_builtin, LEX_BUILTIN, NOT_OLD|A(1), do_system},
{"systime", Node_builtin, LEX_BUILTIN, GAWKX|A(0), do_systime},
{"tolower", Node_builtin, LEX_BUILTIN, NOT_OLD|A(1), do_tolower},
{"toupper", Node_builtin, LEX_BUILTIN, NOT_OLD|A(1), do_toupper},
{"while", Node_K_while, LEX_WHILE, 0, 0},
};
/* VARARGS0 */
static void
yyerror(va_alist)
va_dcl
{
va_list args;
char *mesg = NULL;
register char *bp, *cp;
char *scan;
char buf[120];
errcount++;
/* Find the current line in the input file */
if (lexptr) {
if (!thisline) {
cp = lexeme;
if (*cp == '\n') {
cp--;
mesg = "unexpected newline";
}
for ( ; cp != lexptr_begin && *cp != '\n'; --cp)
;
if (*cp == '\n')
cp++;
thisline = cp;
}
/* NL isn't guaranteed */
bp = lexeme;
while (bp < lexend && *bp && *bp != '\n')
bp++;
} else {
thisline = "(END OF FILE)";
bp = thisline + 13;
}
msg("%.*s", (int) (bp - thisline), thisline);
bp = buf;
cp = buf + sizeof(buf) - 24; /* 24 more than longest msg. input */
if (lexptr) {
scan = thisline;
while (bp < cp && scan < lexeme)
if (*scan++ == '\t')
*bp++ = '\t';
else
*bp++ = ' ';
*bp++ = '^';
*bp++ = ' ';
}
va_start(args);
if (mesg == NULL)
mesg = va_arg(args, char *);
strcpy(bp, mesg);
err("", buf, args);
va_end(args);
exit(2);
}
static char *
get_src_buf()
{
static int samefile = 0;
static int nextfile = 0;
static char *buf = NULL;
static int fd;
int n;
register char *scan;
static int len = 0;
static int did_newline = 0;
# define SLOP 128 /* enough space to hold most source lines */
if (nextfile > numfiles)
return NULL;
if (srcfiles[nextfile].stype == CMDLINE) {
if (len == 0) {
len = strlen(srcfiles[nextfile].val);
sourceline = 1;
lexptr = lexptr_begin = srcfiles[nextfile].val;
lexend = lexptr + len;
} else if (!did_newline && *(lexptr-1) != '\n') {
/*
* The following goop is to ensure that the source
* ends with a newline and that the entire current
* line is available for error messages.
*/
int offset;
did_newline = 1;
offset = lexptr - lexeme;
for (scan = lexeme; scan > lexptr_begin; scan--)
if (*scan == '\n') {
scan++;
break;
}
len = lexptr - scan;
emalloc(buf, char *, len+1, "get_src_buf");
memcpy(buf, scan, len);
thisline = buf;
lexptr = buf + len;
*lexptr = '\n';
lexeme = lexptr - offset;
lexptr_begin = buf;
lexend = lexptr + 1;
} else {
len = 0;
lexeme = lexptr = lexptr_begin = NULL;
}
if (lexptr == NULL && ++nextfile <= numfiles)
return get_src_buf();
return lexptr;
}
if (!samefile) {
source = srcfiles[nextfile].val;
if (source == NULL) {
if (buf) {
free(buf);
buf = NULL;
}
len = 0;
return lexeme = lexptr = lexptr_begin = NULL;
}
fd = pathopen(source);
if (fd == -1)
fatal("can't open source file \"%s\" for reading (%s)",
source, strerror(errno));
len = optimal_bufsize(fd);
if (buf)
free(buf);
emalloc(buf, char *, len + SLOP, "get_src_buf");
lexptr_begin = buf + SLOP;
samefile = 1;
sourceline = 1;
} else {
/*
* Here, we retain the current source line (up to length SLOP)
* in the beginning of the buffer that was overallocated above
*/
int offset;
int linelen;
offset = lexptr - lexeme;
for (scan = lexeme; scan > lexptr_begin; scan--)
if (*scan == '\n') {
scan++;
break;
}
linelen = lexptr - scan;
if (linelen > SLOP)
linelen = SLOP;
thisline = buf + SLOP - linelen;
memcpy(thisline, scan, linelen);
lexeme = buf + SLOP - offset;
lexptr_begin = thisline;
}
n = read(fd, buf + SLOP, len);
if (n == -1)
fatal("can't read sourcefile \"%s\" (%s)",
source, strerror(errno));
if (n == 0) {
samefile = 0;
nextfile++;
len = 0;
return get_src_buf();
}
lexptr = buf + SLOP;
lexend = lexptr + n;
return buf;
}
#define tokadd(x) (*token++ = (x), token == tokend ? tokexpand() : token)
char *
tokexpand()
{
static int toksize = 60;
int tokoffset;
tokoffset = token - tokstart;
toksize *= 2;
if (tokstart)
erealloc(tokstart, char *, toksize, "tokexpand");
else
emalloc(tokstart, char *, toksize, "tokexpand");
tokend = tokstart + toksize;
token = tokstart + tokoffset;
return token;
}
#if DEBUG
char
nextc() {
if (lexptr && lexptr < lexend)
return *lexptr++;
else if (get_src_buf())
return *lexptr++;
else
return '\0';
}
#else
#define nextc() ((lexptr && lexptr < lexend) ? \
*lexptr++ : \
(get_src_buf() ? *lexptr++ : '\0') \
)
#endif
#define pushback() (lexptr && lexptr > lexptr_begin ? lexptr-- : lexptr)
/*
* Read the input and turn it into tokens.
*/
static int
yylex()
{
register int c;
int seen_e = 0; /* These are for numbers */
int seen_point = 0;
int esc_seen; /* for literal strings */
int low, mid, high;
static int did_newline = 0;
char *tokkey;
if (!nextc())
return 0;
pushback();
lexeme = lexptr;
thisline = NULL;
if (want_regexp) {
int in_brack = 0;
want_regexp = 0;
token = tokstart;
while ((c = nextc()) != 0) {
switch (c) {
case '[':
in_brack = 1;
break;
case ']':
in_brack = 0;
break;
case '\\':
if ((c = nextc()) == '\0') {
yyerror("unterminated regexp ends with \\ at end of file");
} else if (c == '\n') {
sourceline++;
continue;
} else
tokadd('\\');
break;
case '/': /* end of the regexp */
if (in_brack)
break;
pushback();
tokadd('\0');
yylval.sval = tokstart;
return REGEXP;
case '\n':
pushback();
yyerror("unterminated regexp");
case '\0':
yyerror("unterminated regexp at end of file");
}
tokadd(c);
}
}
retry:
while ((c = nextc()) == ' ' || c == '\t')
;
lexeme = lexptr ? lexptr - 1 : lexptr;
thisline = NULL;
token = tokstart;
yylval.nodetypeval = Node_illegal;
switch (c) {
case 0:
return 0;
case '\n':
sourceline++;
return NEWLINE;
case '#': /* it's a comment */
while ((c = nextc()) != '\n') {
if (c == '\0')
return 0;
}
sourceline++;
return NEWLINE;
case '\\':
#ifdef RELAXED_CONTINUATION
if (!do_unix) { /* strip trailing white-space and/or comment */
while ((c = nextc()) == ' ' || c == '\t') continue;
if (c == '#')
while ((c = nextc()) != '\n') if (!c) break;
pushback();
}
#endif /*RELAXED_CONTINUATION*/
if (nextc() == '\n') {
sourceline++;
goto retry;
} else
yyerror("inappropriate use of backslash");
break;
case '$':
want_assign = 1;
return '$';
case ')':
case ']':
case '(':
case '[':
case ';':
case ':':
case '?':
case '{':
case ',':
return c;
case '*':
if ((c = nextc()) == '=') {
yylval.nodetypeval = Node_assign_times;
return ASSIGNOP;
} else if (do_posix) {
pushback();
return '*';
} else if (c == '*') {
/* make ** and **= aliases for ^ and ^= */
static int did_warn_op = 0, did_warn_assgn = 0;
if (nextc() == '=') {
if (do_lint && ! did_warn_assgn) {
did_warn_assgn = 1;
warning("**= is not allowed by POSIX");
}
yylval.nodetypeval = Node_assign_exp;
return ASSIGNOP;
} else {
pushback();
if (do_lint && ! did_warn_op) {
did_warn_op = 1;
warning("** is not allowed by POSIX");
}
return '^';
}
}
pushback();
return '*';
case '/':
if (want_assign) {
if (nextc() == '=') {
yylval.nodetypeval = Node_assign_quotient;
return ASSIGNOP;
}
pushback();
}
return '/';
case '%':
if (nextc() == '=') {
yylval.nodetypeval = Node_assign_mod;
return ASSIGNOP;
}
pushback();
return '%';
case '^':
{
static int did_warn_op = 0, did_warn_assgn = 0;
if (nextc() == '=') {
if (do_lint && ! did_warn_assgn) {
did_warn_assgn = 1;
warning("operator `^=' is not supported in old awk");
}
yylval.nodetypeval = Node_assign_exp;
return ASSIGNOP;
}
pushback();
if (do_lint && ! did_warn_op) {
did_warn_op = 1;
warning("operator `^' is not supported in old awk");
}
return '^';
}
case '+':
if ((c = nextc()) == '=') {
yylval.nodetypeval = Node_assign_plus;
return ASSIGNOP;
}
if (c == '+')
return INCREMENT;
pushback();
return '+';
case '!':
if ((c = nextc()) == '=') {
yylval.nodetypeval = Node_notequal;
return RELOP;
}
if (c == '~') {
yylval.nodetypeval = Node_nomatch;
want_assign = 0;
return MATCHOP;
}
pushback();
return '!';
case '<':
if (nextc() == '=') {
yylval.nodetypeval = Node_leq;
return RELOP;
}
yylval.nodetypeval = Node_less;
pushback();
return '<';
case '=':
if (nextc() == '=') {
yylval.nodetypeval = Node_equal;
return RELOP;
}
yylval.nodetypeval = Node_assign;
pushback();
return ASSIGNOP;
case '>':
if ((c = nextc()) == '=') {
yylval.nodetypeval = Node_geq;
return RELOP;
} else if (c == '>') {
yylval.nodetypeval = Node_redirect_append;
return APPEND_OP;
}
yylval.nodetypeval = Node_greater;
pushback();
return '>';
case '~':
yylval.nodetypeval = Node_match;
want_assign = 0;
return MATCHOP;
case '}':
/*
* Added did newline stuff. Easier than
* hacking the grammar
*/
if (did_newline) {
did_newline = 0;
return c;
}
did_newline++;
--lexptr; /* pick up } next time */
return NEWLINE;
case '"':
esc_seen = 0;
while ((c = nextc()) != '"') {
if (c == '\n') {
pushback();
yyerror("unterminated string");
}
if (c == '\\') {
c = nextc();
if (c == '\n') {
sourceline++;
continue;
}
esc_seen = 1;
tokadd('\\');
}
if (c == '\0') {
pushback();
yyerror("unterminated string");
}
tokadd(c);
}
yylval.nodeval = make_str_node(tokstart,
token - tokstart, esc_seen ? SCAN : 0);
yylval.nodeval->flags |= PERM;
return YSTRING;
case '-':
if ((c = nextc()) == '=') {
yylval.nodetypeval = Node_assign_minus;
return ASSIGNOP;
}
if (c == '-')
return DECREMENT;
pushback();
return '-';
case '.':
c = nextc();
pushback();
if (!isdigit(c))
return '.';
else
c = '.'; /* FALL THROUGH */
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
/* It's a number */
for (;;) {
int gotnumber = 0;
tokadd(c);
switch (c) {
case '.':
if (seen_point) {
gotnumber++;
break;
}
++seen_point;
break;
case 'e':
case 'E':
if (seen_e) {
gotnumber++;
break;
}
++seen_e;
if ((c = nextc()) == '-' || c == '+')
tokadd(c);
else
pushback();
break;
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
break;
default:
gotnumber++;
}
if (gotnumber)
break;
c = nextc();
}
pushback();
yylval.nodeval = make_number(atof(tokstart));
yylval.nodeval->flags |= PERM;
return YNUMBER;
case '&':
if ((c = nextc()) == '&') {
yylval.nodetypeval = Node_and;
for (;;) {
c = nextc();
if (c == '\0')
break;
if (c == '#') {
while ((c = nextc()) != '\n' && c != '\0')
;
if (c == '\0')
break;
}
if (c == '\n')
sourceline++;
if (! isspace(c)) {
pushback();
break;
}
}
want_assign = 0;
return LEX_AND;
}
pushback();
return '&';
case '|':
if ((c = nextc()) == '|') {
yylval.nodetypeval = Node_or;
for (;;) {
c = nextc();
if (c == '\0')
break;
if (c == '#') {
while ((c = nextc()) != '\n' && c != '\0')
;
if (c == '\0')
break;
}
if (c == '\n')
sourceline++;
if (! isspace(c)) {
pushback();
break;
}
}
want_assign = 0;
return LEX_OR;
}
pushback();
return '|';
}
if (c != '_' && ! isalpha(c))
yyerror("Invalid char '%c' in expression\n", c);
/* it's some type of name-type-thing. Find its length */
token = tokstart;
while (is_identchar(c)) {
tokadd(c);
c = nextc();
}
tokadd('\0');
emalloc(tokkey, char *, token - tokstart, "yylex");
memcpy(tokkey, tokstart, token - tokstart);
pushback();
/* See if it is a special token. */
low = 0;
high = (sizeof (tokentab) / sizeof (tokentab[0])) - 1;
while (low <= high) {
int i/* , c */;
mid = (low + high) / 2;
c = *tokstart - tokentab[mid].operator[0];
i = c ? c : strcmp (tokstart, tokentab[mid].operator);
if (i < 0) { /* token < mid */
high = mid - 1;
} else if (i > 0) { /* token > mid */
low = mid + 1;
} else {
if (do_lint) {
if (tokentab[mid].flags & GAWKX)
warning("%s() is a gawk extension",
tokentab[mid].operator);
if (tokentab[mid].flags & NOT_POSIX)
warning("POSIX does not allow %s",
tokentab[mid].operator);
if (tokentab[mid].flags & NOT_OLD)
warning("%s is not supported in old awk",
tokentab[mid].operator);
}
if ((do_unix && (tokentab[mid].flags & GAWKX))
|| (do_posix && (tokentab[mid].flags & NOT_POSIX)))
break;
if (tokentab[mid].class == LEX_BUILTIN
|| tokentab[mid].class == LEX_LENGTH
)
yylval.lval = mid;
else
yylval.nodetypeval = tokentab[mid].value;
return tokentab[mid].class;
}
}
yylval.sval = tokkey;
if (*lexptr == '(')
return FUNC_CALL;
else {
want_assign = 1;
return NAME;
}
}
static NODE *
node_common(op)
NODETYPE op;
{
register NODE *r;
getnode(r);
r->type = op;
r->flags = MALLOC;
/* if lookahead is NL, lineno is 1 too high */
if (lexeme && *lexeme == '\n')
r->source_line = sourceline - 1;
else
r->source_line = sourceline;
r->source_file = source;
return r;
}
/*
* This allocates a node with defined lnode and rnode.
*/
NODE *
node(left, op, right)
NODE *left, *right;
NODETYPE op;
{
register NODE *r;
r = node_common(op);
r->lnode = left;
r->rnode = right;
return r;
}
/*
* This allocates a node with defined subnode and proc for builtin functions
* Checks for arg. count and supplies defaults where possible.
*/
static NODE *
snode(subn, op, idx)
NODETYPE op;
int idx;
NODE *subn;
{
register NODE *r;
register NODE *n;
int nexp = 0;
int args_allowed;
r = node_common(op);
/* traverse expression list to see how many args. given */
for (n= subn; n; n= n->rnode) {
nexp++;
if (nexp > 3)
break;
}
/* check against how many args. are allowed for this builtin */
args_allowed = tokentab[idx].flags & ARGS;
if (args_allowed && !(args_allowed & A(nexp)))
fatal("%s() cannot have %d argument%c",
tokentab[idx].operator, nexp, nexp == 1 ? ' ' : 's');
r->proc = tokentab[idx].ptr;
/* special case processing for a few builtins */
if (nexp == 0 && r->proc == do_length) {
subn = node(node(make_number(0.0),Node_field_spec,(NODE *)NULL),
Node_expression_list,
(NODE *) NULL);
} else if (r->proc == do_match) {
if (subn->rnode->lnode->type != Node_regex)
subn->rnode->lnode = mk_rexp(subn->rnode->lnode);
} else if (r->proc == do_sub || r->proc == do_gsub) {
if (subn->lnode->type != Node_regex)
subn->lnode = mk_rexp(subn->lnode);
if (nexp == 2)
append_right(subn, node(node(make_number(0.0),
Node_field_spec,
(NODE *) NULL),
Node_expression_list,
(NODE *) NULL));
else if (do_lint && subn->rnode->rnode->lnode->type == Node_val)
warning("string literal as last arg of substitute");
} else if (r->proc == do_split) {
if (nexp == 2)
append_right(subn,
node(FS_node, Node_expression_list, (NODE *) NULL));
n = subn->rnode->rnode->lnode;
if (n->type != Node_regex)
subn->rnode->rnode->lnode = mk_rexp(n);
if (nexp == 2)
subn->rnode->rnode->lnode->re_flags |= FS_DFLT;
}
r->subnode = subn;
return r;
}
/*
* This allocates a Node_line_range node with defined condpair and
* zeroes the trigger word to avoid the temptation of assuming that calling
* 'node( foo, Node_line_range, 0)' will properly initialize 'triggered'.
*/
/* Otherwise like node() */
static NODE *
mkrangenode(cpair)
NODE *cpair;
{
register NODE *r;
getnode(r);
r->type = Node_line_range;
r->condpair = cpair;
r->triggered = 0;
return r;
}
/* Build a for loop */
static NODE *
make_for_loop(init, cond, incr)
NODE *init, *cond, *incr;
{
register FOR_LOOP_HEADER *r;
NODE *n;
emalloc(r, FOR_LOOP_HEADER *, sizeof(FOR_LOOP_HEADER), "make_for_loop");
getnode(n);
n->type = Node_illegal;
r->init = init;
r->cond = cond;
r->incr = incr;
n->sub.nodep.r.hd = r;
return n;
}
/*
* Install a name in the symbol table, even if it is already there.
* Caller must check against redefinition if that is desired.
*/
NODE *
install(name, value)
char *name;
NODE *value;
{
register NODE *hp;
register int len, bucket;
len = strlen(name);
bucket = hash(name, len);
getnode(hp);
hp->type = Node_hashnode;
hp->hnext = variables[bucket];
variables[bucket] = hp;
hp->hlength = len;
hp->hvalue = value;
hp->hname = name;
hp->hvalue->vname = name;
return hp->hvalue;
}
/* find the most recent hash node for name installed by install */
NODE *
lookup(name)
char *name;
{
register NODE *bucket;
register int len;
len = strlen(name);
bucket = variables[hash(name, len)];
while (bucket) {
if (bucket->hlength == len && STREQN(bucket->hname, name, len))
return bucket->hvalue;
bucket = bucket->hnext;
}
return NULL;
}
/*
* Add new to the rightmost branch of LIST. This uses n^2 time, so we make
* a simple attempt at optimizing it.
*/
static NODE *
append_right(list, new)
NODE *list, *new;
{
register NODE *oldlist;
static NODE *savefront = NULL, *savetail = NULL;
oldlist = list;
if (savefront == oldlist) {
savetail = savetail->rnode = new;
return oldlist;
} else
savefront = oldlist;
while (list->rnode != NULL)
list = list->rnode;
savetail = list->rnode = new;
return oldlist;
}
/*
* check if name is already installed; if so, it had better have Null value,
* in which case def is added as the value. Otherwise, install name with def
* as value.
*/
static void
func_install(params, def)
NODE *params;
NODE *def;
{
NODE *r;
pop_params(params->rnode);
pop_var(params, 0);
r = lookup(params->param);
if (r != NULL) {
fatal("function name `%s' previously defined", params->param);
} else
(void) install(params->param, node(params, Node_func, def));
}
static void
pop_var(np, freeit)
NODE *np;
int freeit;
{
register NODE *bucket, **save;
register int len;
char *name;
name = np->param;
len = strlen(name);
save = &(variables[hash(name, len)]);
for (bucket = *save; bucket; bucket = bucket->hnext) {
if (len == bucket->hlength && STREQN(bucket->hname, name, len)) {
*save = bucket->hnext;
freenode(bucket);
if (freeit)
free(np->param);
return;
}
save = &(bucket->hnext);
}
}
static void
pop_params(params)
NODE *params;
{
register NODE *np;
for (np = params; np != NULL; np = np->rnode)
pop_var(np, 1);
}
static NODE *
make_param(name)
char *name;
{
NODE *r;
getnode(r);
r->type = Node_param_list;
r->rnode = NULL;
r->param = name;
r->param_cnt = param_counter++;
return (install(name, r));
}
/* Name points to a variable name. Make sure its in the symbol table */
NODE *
variable(name, can_free)
char *name;
int can_free;
{
register NODE *r;
static int env_loaded = 0;
if (!env_loaded && STREQ(name, "ENVIRON")) {
load_environ();
env_loaded = 1;
}
if ((r = lookup(name)) == NULL)
r = install(name, node(Nnull_string, Node_var, (NODE *) NULL));
else if (can_free)
free(name);
return r;
}
static NODE *
mk_rexp(exp)
NODE *exp;
{
if (exp->type == Node_regex)
return exp;
else {
NODE *n;
getnode(n);
n->type = Node_regex;
n->re_exp = exp;
n->re_text = NULL;
n->re_reg = NULL;
n->re_flags = 0;
n->re_cnt = 1;
return n;
}
}