NetBSD/gnu/usr.bin/awk/parse.y

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/********************************************
parse.y
copyright 1991, Michael D. Brennan
This is a source file for mawk, an implementation of
the AWK programming language.
Mawk is distributed without warranty under the terms of
the GNU General Public License, version 2, 1991.
********************************************/
/* $Log: parse.y,v $
/* Revision 1.2 1993/07/02 23:57:44 jtc
/* Updated to mawk 1.1.4
/*
* Revision 5.4.1.1 1993/05/05 00:08:26 mike
* patch4: forgot to set $$ in LENGTH alone production
*
* Revision 5.4 1992/08/08 17:17:20 brennan
* patch 2: improved timing of error recovery in
* bungled function definitions. Fixes a core dump
*
* Revision 5.3 1992/07/08 15:43:41 brennan
* patch2: length returns. I am a wimp
*
* Revision 5.2 1992/01/08 16:11:42 brennan
* code FE_PUSHA carefully for MSDOS large mode
*
* Revision 5.1 91/12/05 07:50:22 brennan
* 1.1 pre-release
*
*/
%{
#include <stdio.h>
#include "mawk.h"
#include "code.h"
#include "symtype.h"
#include "memory.h"
#include "bi_funct.h"
#include "bi_vars.h"
#include "jmp.h"
#include "field.h"
#include "files.h"
#ifdef YYXBYACC
#define YYBYACC 1
#endif
#define YYMAXDEPTH 200
/* Bison's use of MSDOS and ours clashes */
#undef MSDOS
extern void PROTO( eat_nl, (void) ) ;
static void PROTO( resize_fblock, (FBLOCK *, INST *) ) ;
static void PROTO( code_array, (SYMTAB *) ) ;
static void PROTO( code_call_id, (CA_REC *, SYMTAB *) ) ;
static void PROTO( field_A2I, (void)) ;
static int PROTO( current_offset, (void) ) ;
static void PROTO( check_var, (SYMTAB *) ) ;
static void PROTO( check_array, (SYMTAB *) ) ;
static void PROTO( RE_as_arg, (void)) ;
static int scope ;
static FBLOCK *active_funct ;
/* when scope is SCOPE_FUNCT */
#define code_address(x) if( is_local(x) )\
{ code1(L_PUSHA) ; code1((x)->offset) ; }\
else code2(_PUSHA, (x)->stval.cp)
/* this nonsense caters to MSDOS large model */
#define CODE_FE_PUSHA() code_ptr->ptr = (PTR) 0 ; code1(FE_PUSHA)
%}
%union{
CELL *cp ;
SYMTAB *stp ;
INST *start ; /* code starting address */
PF_CP fp ; /* ptr to a (print/printf) or (sub/gsub) function */
BI_REC *bip ; /* ptr to info about a builtin */
FBLOCK *fbp ; /* ptr to a function block */
ARG2_REC *arg2p ;
CA_REC *ca_p ;
int ival ;
PTR ptr ;
}
/* two tokens to help with errors */
%token UNEXPECTED /* unexpected character */
%token BAD_DECIMAL
%token NL
%token SEMI_COLON
%token LBRACE RBRACE
%token LBOX RBOX
%token COMMA
%token <ival> IO_OUT /* > or output pipe */
%right ASSIGN ADD_ASG SUB_ASG MUL_ASG DIV_ASG MOD_ASG POW_ASG
%right QMARK COLON
%left OR
%left AND
%left IN
%left <ival> MATCH /* ~ or !~ */
%left EQ NEQ LT LTE GT GTE
%left CAT
%left GETLINE
%left PLUS MINUS
%left MUL DIV MOD
%left NOT UMINUS
%nonassoc IO_IN PIPE
%right POW
%left <ival> INC_or_DEC
%left DOLLAR FIELD /* last to remove a SR conflict
with getline */
%right LPAREN RPAREN /* removes some SR conflicts */
%token <ptr> DOUBLE STRING_ RE
%token <stp> ID D_ID
%token <fbp> FUNCT_ID
%token <bip> BUILTIN LENGTH
%token <cp> FIELD
%token PRINT PRINTF SPLIT MATCH_FUNC SUB GSUB
/* keywords */
%token DO WHILE FOR BREAK CONTINUE IF ELSE IN
%token DELETE BEGIN END EXIT NEXT RETURN FUNCTION
%type <start> block block_or_separator
%type <start> statement_list statement mark
%type <ival> pr_args
%type <arg2p> arg2
%type <start> builtin
%type <start> getline_file
%type <start> lvalue field fvalue
%type <start> expr cat_expr p_expr
%type <start> while_front if_front
%type <start> for1 for2
%type <start> array_loop_front
%type <start> return_statement
%type <start> split_front re_arg sub_back
%type <ival> arglist args
%type <fp> print sub_or_gsub
%type <fbp> funct_start funct_head
%type <ca_p> call_args ca_front ca_back
%type <ival> f_arglist f_args
%%
/* productions */
program : program_block
| program program_block
;
program_block : PA_block /* pattern-action */
| function_def
| outside_error block
;
PA_block : block
{ /* this do nothing action removes a vacuous warning
from Bison */
}
| BEGIN
{
be_expand(&begin_code) ;
scope = SCOPE_BEGIN ;
}
block
{ be_shrink(&begin_code) ;
scope = SCOPE_MAIN ;
}
| END
{
be_expand(&end_code) ;
scope = SCOPE_END ;
}
block
{ be_shrink(&end_code) ;
scope = SCOPE_MAIN ;
}
| expr /* this works just like an if statement */
{ code_jmp(_JZ, (INST*)0) ; }
block_or_separator
{ patch_jmp( code_ptr ) ; }
/* range pattern, see comment in execute.c near _RANGE */
| expr COMMA
{ code_push($1, code_ptr - $1) ;
code_ptr = $1 ;
code1(_RANGE) ; code1(1) ;
code_ptr += 3 ;
code_ptr += code_pop(code_ptr) ;
code1(_STOP) ;
$1[2].op = code_ptr - ($1+1) ;
}
expr
{ code1(_STOP) ; }
block_or_separator
{ $1[3].op = $6 - ($1+1) ;
$1[4].op = code_ptr - ($1+1) ;
}
;
block : LBRACE statement_list RBRACE
{ $$ = $2 ; }
| LBRACE error RBRACE
{ $$ = code_ptr ; /* does nothing won't be executed */
print_flag = getline_flag = paren_cnt = 0 ;
yyerrok ; }
;
block_or_separator : block
| separator /* default print action */
{ $$ = code_ptr ;
code1(_PUSHINT) ; code1(0) ;
code2(_PRINT, bi_print) ;
}
statement_list : statement
| statement_list statement
;
statement : block
| expr separator
{ code1(_POP) ; }
| /* empty */ separator
{ $$ = code_ptr ; }
| error separator
{ $$ = code_ptr ;
print_flag = getline_flag = 0 ;
paren_cnt = 0 ;
yyerrok ;
}
| BREAK separator
{ $$ = code_ptr ; BC_insert('B', code_ptr+1) ;
code2(_JMP, 0) /* don't use code_jmp ! */ ; }
| CONTINUE separator
{ $$ = code_ptr ; BC_insert('C', code_ptr+1) ;
code2(_JMP, 0) ; }
| return_statement
{ if ( scope != SCOPE_FUNCT )
compile_error("return outside function body") ;
}
| NEXT separator
{ if ( scope != SCOPE_MAIN )
compile_error( "improper use of next" ) ;
$$ = code_ptr ;
code1(_NEXT) ;
}
;
separator : NL | SEMI_COLON
;
expr : cat_expr
| lvalue ASSIGN expr { code1(_ASSIGN) ; }
| lvalue ADD_ASG expr { code1(_ADD_ASG) ; }
| lvalue SUB_ASG expr { code1(_SUB_ASG) ; }
| lvalue MUL_ASG expr { code1(_MUL_ASG) ; }
| lvalue DIV_ASG expr { code1(_DIV_ASG) ; }
| lvalue MOD_ASG expr { code1(_MOD_ASG) ; }
| lvalue POW_ASG expr { code1(_POW_ASG) ; }
| expr EQ expr { code1(_EQ) ; }
| expr NEQ expr { code1(_NEQ) ; }
| expr LT expr { code1(_LT) ; }
| expr LTE expr { code1(_LTE) ; }
| expr GT expr { code1(_GT) ; }
| expr GTE expr { code1(_GTE) ; }
| expr MATCH expr
{
if ( $3 == code_ptr - 2 )
{
if ( $3->op == _MATCH0 ) $3->op = _MATCH1 ;
else /* check for string */
if ( $3->op == _PUSHS )
{ CELL *cp = ZMALLOC(CELL) ;
cp->type = C_STRING ;
cp->ptr = $3[1].ptr ;
cast_to_RE(cp) ;
code_ptr -= 2 ;
code2(_MATCH1, cp->ptr) ;
ZFREE(cp) ;
}
else code1(_MATCH2) ;
}
else code1(_MATCH2) ;
if ( !$2 ) code1(_NOT) ;
}
/* short circuit boolean evaluation */
| expr OR
{ code1(_DUP) ;
code_jmp(_JNZ, (INST*)0) ;
code1(_POP) ;
}
expr
{ patch_jmp(code_ptr) ; code1(_TEST) ; }
| expr AND
{ code1(_DUP) ; code_jmp(_JZ, (INST*)0) ;
code1(_POP) ; }
expr
{ patch_jmp(code_ptr) ; code1(_TEST) ; }
| expr QMARK { code_jmp(_JZ, (INST*)0) ; }
expr COLON { code_jmp(_JMP, (INST*)0) ; }
expr
{ patch_jmp(code_ptr) ; patch_jmp($7) ; }
;
cat_expr : p_expr %prec CAT
| cat_expr p_expr %prec CAT
{ code1(_CAT) ; }
;
p_expr : DOUBLE
{ $$ = code_ptr ; code2(_PUSHD, $1) ; }
| STRING_
{ $$ = code_ptr ; code2(_PUSHS, $1) ; }
| ID %prec AND /* anything less than IN */
{ check_var($1) ;
$$ = code_ptr ;
if ( is_local($1) )
{ code1(L_PUSHI) ; code1($1->offset) ; }
else code2(_PUSHI, $1->stval.cp) ;
}
| LPAREN expr RPAREN
{ $$ = $2 ; }
;
p_expr : RE
{ $$ = code_ptr ; code2(_MATCH0, $1) ; }
;
p_expr : p_expr PLUS p_expr { code1(_ADD) ; }
| p_expr MINUS p_expr { code1(_SUB) ; }
| p_expr MUL p_expr { code1(_MUL) ; }
| p_expr DIV p_expr { code1(_DIV) ; }
| p_expr MOD p_expr { code1(_MOD) ; }
| p_expr POW p_expr { code1(_POW) ; }
| NOT p_expr
{ $$ = $2 ; code1(_NOT) ; }
| PLUS p_expr %prec UMINUS
{ $$ = $2 ; code1(_UPLUS) ; }
| MINUS p_expr %prec UMINUS
{ $$ = $2 ; code1(_UMINUS) ; }
| builtin
;
p_expr : ID INC_or_DEC
{ check_var($1) ;
$$ = code_ptr ;
code_address($1) ;
if ( $2 == '+' ) code1(_POST_INC) ;
else code1(_POST_DEC) ;
}
| INC_or_DEC lvalue
{ $$ = $2 ;
if ( $1 == '+' ) code1(_PRE_INC) ;
else code1(_PRE_DEC) ;
}
;
p_expr : field INC_or_DEC
{ if ($2 == '+' ) code1(F_POST_INC ) ;
else code1(F_POST_DEC) ;
}
| INC_or_DEC field
{ $$ = $2 ;
if ( $1 == '+' ) code1(F_PRE_INC) ;
else code1( F_PRE_DEC) ;
}
;
lvalue : ID
{ $$ = code_ptr ;
check_var($1) ;
code_address($1) ;
}
;
arglist : /* empty */
{ $$ = 0 ; }
| args
;
args : expr %prec LPAREN
{ $$ = 1 ; }
| args COMMA expr
{ $$ = $1 + 1 ; }
;
builtin :
BUILTIN mark LPAREN arglist RPAREN
{ BI_REC *p = $1 ;
$$ = $2 ;
if ( p-> min_args > $4 || p->max_args < $4 )
compile_error(
"wrong number of arguments in call to %s" ,
p->name ) ;
if ( p->min_args != p->max_args ) /* variable args */
{ code1(_PUSHINT) ; code1($4) ; }
code2(_BUILTIN , p->fp) ;
}
| LENGTH /* this is an irritation */
{ $$ = code_ptr ;
code1(_PUSHINT) ; code1(0) ;
code2(_BUILTIN, $1->fp) ;
}
;
/* an empty production to store the code_ptr */
mark : /* empty */
{ $$ = code_ptr ; }
/* print_statement */
statement : print mark pr_args pr_direction separator
{ code2(_PRINT, $1) ; $$ = $2 ;
if ( $1 == bi_printf && $3 == 0 )
compile_error("no arguments in call to printf") ;
print_flag = 0 ;
$$ = $2 ;
}
;
print : PRINT { $$ = bi_print ; print_flag = 1 ;}
| PRINTF { $$ = bi_printf ; print_flag = 1 ; }
;
pr_args : arglist { code1(_PUSHINT) ; code1($1) ; }
| LPAREN arg2 RPAREN
{ $$ = $2->cnt ; zfree($2,sizeof(ARG2_REC)) ;
code1(_PUSHINT) ; code1($$) ;
}
| LPAREN RPAREN
{ $$=0 ; code1(_PUSHINT) ; code1(0) ; }
;
arg2 : expr COMMA expr
{ $$ = (ARG2_REC*) zmalloc(sizeof(ARG2_REC)) ;
$$->start = $1 ;
$$->cnt = 2 ;
}
| arg2 COMMA expr
{ $$ = $1 ; $$->cnt++ ; }
;
pr_direction : /* empty */
| IO_OUT expr
{ code1(_PUSHINT) ; code1($1) ; }
;
/* IF and IF-ELSE */
if_front : IF LPAREN expr RPAREN
{ $$ = $3 ; eat_nl() ; code_jmp(_JZ, (INST*)0) ; }
;
/* if_statement */
statement : if_front statement
{ patch_jmp( code_ptr ) ; }
;
else : ELSE { eat_nl() ; code_jmp(_JMP, (INST*)0) ; }
;
/* if_else_statement */
statement : if_front statement else statement
{ patch_jmp(code_ptr) ; patch_jmp($4) ; }
/* LOOPS */
do : DO
{ eat_nl() ; BC_new() ; }
;
/* do_statement */
statement : do statement WHILE LPAREN expr RPAREN separator
{ $$ = $2 ;
code_jmp(_JNZ, $2) ;
BC_clear(code_ptr, $5) ; }
;
while_front : WHILE LPAREN expr RPAREN
{ eat_nl() ; BC_new() ;
$$ = $3 ;
/* check if const expression */
if ( code_ptr - 2 == $3 &&
code_ptr[-2].op == _PUSHD &&
*(double*)code_ptr[-1].ptr != 0.0
)
code_ptr -= 2 ;
else
{
code_push($3, code_ptr-$3) ;
code_ptr = $3 ;
code2(_JMP, (INST*)0) ; /* code2() not code_jmp() */
}
}
;
/* while_statement */
statement : while_front statement
{
INST *c_addr ; int len ;
if ( $1 != $2 ) /* real test in loop */
{
$1[1].op = code_ptr-($1+1) ;
c_addr = code_ptr ;
len = code_pop(code_ptr) ;
code_ptr += len ;
code_jmp(_JNZ, $2) ;
BC_clear(code_ptr, c_addr) ;
}
else /* while(1) */
{
code_jmp(_JMP, $1) ;
BC_clear(code_ptr, $2) ;
}
}
;
/* for_statement */
statement : for1 for2 for3 statement
{
INST *cont_address = code_ptr ;
unsigned len = code_pop(code_ptr) ;
code_ptr += len ;
if ( $2 != $4 ) /* real test in for2 */
{
$4[-1].op = code_ptr - $4 + 1 ;
len = code_pop(code_ptr) ;
code_ptr += len ;
code_jmp(_JNZ, $4) ;
}
else /* for(;;) */
code_jmp(_JMP, $4) ;
BC_clear(code_ptr, cont_address) ;
}
;
for1 : FOR LPAREN SEMI_COLON { $$ = code_ptr ; }
| FOR LPAREN expr SEMI_COLON
{ $$ = $3 ; code1(_POP) ; }
;
for2 : SEMI_COLON { $$ = code_ptr ; }
| expr SEMI_COLON
{
if ( code_ptr - 2 == $1 &&
code_ptr[-2].op == _PUSHD &&
* (double*) code_ptr[-1].ptr != 0.0
)
code_ptr -= 2 ;
else
{
code_push($1, code_ptr-$1) ;
code_ptr = $1 ;
code2(_JMP, (INST*)0) ;
}
}
;
for3 : RPAREN
{ eat_nl() ; BC_new() ; code_push((INST*)0,0) ; }
| expr RPAREN
{ eat_nl() ; BC_new() ;
code1(_POP) ;
code_push($1, code_ptr - $1) ;
code_ptr -= code_ptr - $1 ;
}
;
/* arrays */
expr : expr IN ID
{ check_array($3) ;
code_array($3) ;
code1(A_TEST) ;
}
| LPAREN arg2 RPAREN IN ID
{ $$ = $2->start ;
code1(A_CAT) ; code1($2->cnt) ;
zfree($2, sizeof(ARG2_REC)) ;
check_array($5) ;
code_array($5) ;
code1(A_TEST) ;
}
;
lvalue : ID mark LBOX args RBOX
{
if ( $4 > 1 )
{ code1(A_CAT) ; code1($4) ; }
check_array($1) ;
if( is_local($1) )
{ code1(LAE_PUSHA) ; code1($1->offset) ; }
else code2(AE_PUSHA, $1->stval.array) ;
$$ = $2 ;
}
;
p_expr : ID mark LBOX args RBOX %prec AND
{
if ( $4 > 1 )
{ code1(A_CAT) ; code1($4) ; }
check_array($1) ;
if( is_local($1) )
{ code1(LAE_PUSHI) ; code1($1->offset) ; }
else code2(AE_PUSHI, $1->stval.array) ;
$$ = $2 ;
}
| ID mark LBOX args RBOX INC_or_DEC
{
if ( $4 > 1 )
{ code1(A_CAT) ; code1($4) ; }
check_array($1) ;
if( is_local($1) )
{ code1(LAE_PUSHA) ; code1($1->offset) ; }
else code2(AE_PUSHA, $1->stval.array) ;
if ( $6 == '+' ) code1(_POST_INC) ;
else code1(_POST_DEC) ;
$$ = $2 ;
}
;
/* delete A[i] */
statement : DELETE ID mark LBOX args RBOX separator
{
$$ = $3 ;
if ( $5 > 1 ) { code1(A_CAT) ; code1($5) ; }
check_array($2) ;
code_array($2) ;
code1(A_DEL) ;
}
;
/* for ( i in A ) statement */
array_loop_front : FOR LPAREN ID IN ID RPAREN
{ eat_nl() ; BC_new() ;
$$ = code_ptr ;
check_var($3) ;
code_address($3) ;
check_array($5) ;
code_array($5) ;
code2(SET_ALOOP, (INST*)0) ;
}
;
/* array_loop */
statement : array_loop_front statement
{
$2[-1].op = code_ptr - $2 + 1 ;
BC_clear( code_ptr+3 , code_ptr) ;
code_jmp(ALOOP, $2) ;
code_ptr++->ptr = (PTR) ZMALLOC(ALOOP_STATE) ;
}
;
/* fields
D_ID is a special token , same as an ID, but yylex()
only returns it after a '$'. In essense,
DOLLAR D_ID is really one token.
*/
field : FIELD
{ $$ = code_ptr ; code2(F_PUSHA, $1) ; }
| DOLLAR D_ID
{ check_var($2) ;
$$ = code_ptr ;
if ( is_local($2) )
{ code1(L_PUSHI) ; code1($2->offset) ; }
else code2(_PUSHI, $2->stval.cp) ;
CODE_FE_PUSHA() ;
}
| DOLLAR D_ID mark LBOX args RBOX
{
if ( $5 > 1 )
{ code1(A_CAT) ; code1($5) ; }
check_array($2) ;
if( is_local($2) )
{ code1(LAE_PUSHI) ; code1($2->offset) ; }
else code2(AE_PUSHI, $2->stval.array) ;
CODE_FE_PUSHA() ;
$$ = $3 ;
}
| DOLLAR p_expr
{ $$ = $2 ; CODE_FE_PUSHA() ; }
| LPAREN field RPAREN
{ $$ = $2 ; }
;
p_expr : field %prec CAT /* removes field (++|--) sr conflict */
{ field_A2I() ; }
;
expr : field ASSIGN expr { code1(F_ASSIGN) ; }
| field ADD_ASG expr { code1(F_ADD_ASG) ; }
| field SUB_ASG expr { code1(F_SUB_ASG) ; }
| field MUL_ASG expr { code1(F_MUL_ASG) ; }
| field DIV_ASG expr { code1(F_DIV_ASG) ; }
| field MOD_ASG expr { code1(F_MOD_ASG) ; }
| field POW_ASG expr { code1(F_POW_ASG) ; }
;
/* split is handled different than a builtin because
it takes an array and optionally a regular expression as args */
p_expr : split_front split_back
{ code2(_BUILTIN, bi_split) ; }
;
split_front : SPLIT LPAREN expr COMMA ID
{ $$ = $3 ;
check_array($5) ;
code_array($5) ;
}
;
split_back : RPAREN
{ code2(_PUSHI, &fs_shadow) ; }
| COMMA expr RPAREN
{
if ( $2 == code_ptr - 2 )
{
if ( code_ptr[-2].op == _MATCH0 )
RE_as_arg() ;
else
if ( code_ptr[-2].op == _PUSHS )
{ CELL *cp = ZMALLOC(CELL) ;
cp->type = C_STRING ;
cp->ptr = code_ptr[-1].ptr ;
cast_for_split(cp) ;
code_ptr[-2].op = _PUSHC ;
code_ptr[-1].ptr = (PTR) cp ;
}
}
}
;
/* match(expr, RE) */
p_expr : MATCH_FUNC LPAREN expr COMMA re_arg RPAREN
{ $$ = $3 ;
code2(_BUILTIN, bi_match) ;
}
;
re_arg : expr
{
if ( $1 == code_ptr - 2 )
{
if ( $1->op == _MATCH0 ) RE_as_arg() ;
else
if ( $1->op == _PUSHS )
{ CELL *cp = ZMALLOC(CELL) ;
cp->type = C_STRING ;
cp->ptr = $1[1].ptr ;
cast_to_RE(cp) ;
$1->op = _PUSHC ;
$1[1].ptr = (PTR) cp ;
}
}
}
/* exit_statement */
statement : EXIT separator
{ $$ = code_ptr ;
code1(_EXIT0) ; }
| EXIT expr separator
{ $$ = $2 ; code1(_EXIT) ; }
return_statement : RETURN separator
{ $$ = code_ptr ;
code1(_RET0) ; }
| RETURN expr separator
{ $$ = $2 ; code1(_RET) ; }
/* getline */
p_expr : getline %prec GETLINE
{ $$ = code_ptr ;
code2(F_PUSHA, &field[0]) ;
code1(_PUSHINT) ; code1(0) ;
code2(_BUILTIN, bi_getline) ;
getline_flag = 0 ;
}
| getline fvalue %prec GETLINE
{ $$ = $2 ;
code1(_PUSHINT) ; code1(0) ;
code2(_BUILTIN, bi_getline) ;
getline_flag = 0 ;
}
| getline_file p_expr %prec IO_IN
{ code1(_PUSHINT) ; code1(F_IN) ;
code2(_BUILTIN, bi_getline) ;
/* getline_flag already off in yylex() */
}
| p_expr PIPE GETLINE
{ code2(F_PUSHA, &field[0]) ;
code1(_PUSHINT) ; code1(PIPE_IN) ;
code2(_BUILTIN, bi_getline) ;
}
| p_expr PIPE GETLINE fvalue
{
code1(_PUSHINT) ; code1(PIPE_IN) ;
code2(_BUILTIN, bi_getline) ;
}
;
getline : GETLINE { getline_flag = 1 ; }
fvalue : lvalue | field ;
getline_file : getline IO_IN
{ $$ = code_ptr ;
code2(F_PUSHA, field+0) ;
}
| getline fvalue IO_IN
{ $$ = $2 ; }
;
/*==========================================
sub and gsub
==========================================*/
p_expr : sub_or_gsub LPAREN re_arg COMMA expr sub_back
{
if ( $6 - $5 == 2 && $5->op == _PUSHS )
{ /* cast from STRING to REPL at compile time */
CELL *cp = ZMALLOC(CELL) ;
cp->type = C_STRING ;
cp->ptr = $5[1].ptr ;
cast_to_REPL(cp) ;
$5->op = _PUSHC ;
$5[1].ptr = (PTR) cp ;
}
code2(_BUILTIN, $1) ;
$$ = $3 ;
}
;
sub_or_gsub : SUB { $$ = bi_sub ; }
| GSUB { $$ = bi_gsub ; }
;
sub_back : RPAREN /* substitute into $0 */
{ $$ = code_ptr ;
code2(F_PUSHA, &field[0]) ;
}
| COMMA fvalue RPAREN
{ $$ = $2 ; }
;
/*================================================
user defined functions
*=================================*/
function_def : funct_start block
{ resize_fblock($1, code_ptr) ;
code_ptr = main_code_ptr ;
scope = SCOPE_MAIN ;
active_funct = (FBLOCK *) 0 ;
restore_ids() ;
}
;
funct_start : funct_head LPAREN f_arglist RPAREN
{ eat_nl() ;
scope = SCOPE_FUNCT ;
active_funct = $1 ;
main_code_ptr = code_ptr ;
if ( $1->nargs = $3 )
$1->typev = (char *)
memset( zmalloc($3), ST_LOCAL_NONE, SIZE_T($3)) ;
else $1->typev = (char *) 0 ;
code_ptr = $1->code =
(INST *) zmalloc(PAGE_SZ*sizeof(INST)) ;
}
;
funct_head : FUNCTION ID
{ FBLOCK *fbp ;
if ( $2->type == ST_NONE )
{
$2->type = ST_FUNCT ;
fbp = $2->stval.fbp =
(FBLOCK *) zmalloc(sizeof(FBLOCK)) ;
fbp->name = $2->name ;
}
else
{
type_error( $2 ) ;
/* this FBLOCK will not be put in
the symbol table */
fbp = (FBLOCK*) zmalloc(sizeof(FBLOCK)) ;
fbp->name = "" ;
}
$$ = fbp ;
}
| FUNCTION FUNCT_ID
{ $$ = $2 ;
if ( $2->code )
compile_error("redefinition of %s" , $2->name) ;
}
;
f_arglist : /* empty */ { $$ = 0 ; }
| f_args
;
f_args : ID
{ $1 = save_id($1->name) ;
$1->type = ST_LOCAL_NONE ;
$1->offset = 0 ;
$$ = 1 ;
}
| f_args COMMA ID
{ if ( is_local($3) )
compile_error("%s is duplicated in argument list",
$3->name) ;
else
{ $3 = save_id($3->name) ;
$3->type = ST_LOCAL_NONE ;
$3->offset = $1 ;
$$ = $1 + 1 ;
}
}
;
outside_error : error
{ /* we may have to recover from a bungled function
definition */
/* can have local ids, before code scope
changes */
restore_ids() ;
if (scope == SCOPE_FUNCT)
{ scope = SCOPE_MAIN ;
active_funct = (FBLOCK*) 0 ;
}
code_ptr = main_code_ptr ;
}
;
/* a call to a user defined function */
p_expr : FUNCT_ID mark call_args
{ $$ = $2 ;
code2(_CALL, $1) ;
if ( $3 ) code1($3->arg_num+1) ;
else code1(0) ;
check_fcall($1, scope, active_funct,
$3, token_lineno) ;
}
;
call_args : LPAREN RPAREN
{ $$ = (CA_REC *) 0 ; }
| ca_front ca_back
{ $$ = $2 ;
$$->link = $1 ;
$$->arg_num = $1 ? $1->arg_num+1 : 0 ;
}
;
/* The funny definition of ca_front with the COMMA bound to the ID is to
force a shift to avoid a reduce/reduce conflict
ID->id or ID->array
Or to avoid a decision, if the type of the ID has not yet been
determined
*/
ca_front : LPAREN
{ $$ = (CA_REC *) 0 ; }
| ca_front expr COMMA
{ $$ = (CA_REC *) zmalloc(sizeof(CA_REC)) ;
$$->link = $1 ;
$$->type = CA_EXPR ;
$$->arg_num = $1 ? $1->arg_num+1 : 0 ;
}
| ca_front ID COMMA
{ $$ = (CA_REC *) zmalloc(sizeof(CA_REC)) ;
$$->link = $1 ;
$$->arg_num = $1 ? $1->arg_num+1 : 0 ;
code_call_id($$, $2) ;
}
;
ca_back : expr RPAREN
{ $$ = (CA_REC *) zmalloc(sizeof(CA_REC)) ;
$$->type = CA_EXPR ;
}
| ID RPAREN
{ $$ = (CA_REC *) zmalloc(sizeof(CA_REC)) ;
code_call_id($$, $1) ;
}
;
%%
/* resize the code for a user function */
static void resize_fblock( fbp, code_ptr )
FBLOCK *fbp ;
INST *code_ptr ;
{ int size ;
code1(_RET0) ; /* make sure there is always a return statement */
#if !SM_DOS
if ( dump_code )
{ code1(_HALT) ; /*stops da() */
add_to_fdump_list(fbp) ;
}
#endif
if ( (size = code_ptr - fbp->code) > PAGE_SZ-1 )
overflow("function code size", PAGE_SZ ) ;
/* resize the code */
fbp->code = (INST*) zrealloc(fbp->code, PAGE_SZ*sizeof(INST),
size * sizeof(INST) ) ;
}
/* convert FE_PUSHA to FE_PUSHI
or F_PUSH to F_PUSHI
*/
static void field_A2I()
{ CELL *cp ;
if ( code_ptr[-1].op == FE_PUSHA &&
code_ptr[-1].ptr == (PTR) 0)
/* On most architectures, the two tests are the same; a good
compiler might eliminate one. On LM_DOS, and possibly other
segmented architectures, they are not */
{ code_ptr[-1].op = FE_PUSHI ; }
else
{
cp = (CELL *) code_ptr[-1].ptr ;
if ( cp == field ||
#if LM_DOS
SAMESEG(cp,field) &&
#endif
cp > NF && cp <= LAST_PFIELD )
{
code_ptr[-2].op = _PUSHI ;
}
else if ( cp == NF )
{ code_ptr[-2].op = NF_PUSHI ; code_ptr-- ; }
else
{
code_ptr[-2].op = F_PUSHI ;
code_ptr -> op = field_addr_to_index( code_ptr[-1].ptr ) ;
code_ptr++ ;
}
}
}
/* we've seen an ID in a context where it should be a VAR,
check that's consistent with previous usage */
static void check_var( p )
register SYMTAB *p ;
{
switch(p->type)
{
case ST_NONE : /* new id */
p->type = ST_VAR ;
p->stval.cp = new_CELL() ;
p->stval.cp->type = C_NOINIT ;
break ;
case ST_LOCAL_NONE :
p->type = ST_LOCAL_VAR ;
active_funct->typev[p->offset] = ST_LOCAL_VAR ;
break ;
case ST_VAR :
case ST_LOCAL_VAR : break ;
default :
type_error(p) ;
break ;
}
}
/* we've seen an ID in a context where it should be an ARRAY,
check that's consistent with previous usage */
static void check_array(p)
register SYMTAB *p ;
{
switch(p->type)
{
case ST_NONE : /* a new array */
p->type = ST_ARRAY ;
p->stval.array = new_ARRAY() ;
break ;
case ST_ARRAY :
case ST_LOCAL_ARRAY :
break ;
case ST_LOCAL_NONE :
p->type = ST_LOCAL_ARRAY ;
active_funct->typev[p->offset] = ST_LOCAL_ARRAY ;
break ;
default : type_error(p) ; break ;
}
}
static void code_array(p)
register SYMTAB *p ;
{ if ( is_local(p) )
{ code1(LA_PUSHA) ; code1(p->offset) ; }
else code2(A_PUSHA, p->stval.array) ;
}
static int current_offset()
{
switch( scope )
{
case SCOPE_MAIN : return code_ptr - main_start ;
case SCOPE_BEGIN : return code_ptr - begin_code.start ;
case SCOPE_END : return code_ptr - end_code.start ;
case SCOPE_FUNCT : return code_ptr - active_funct->code ;
}
/* can't get here */
return 0 ;
}
/* we've seen an ID as an argument to a user defined function */
static void code_call_id( p, ip )
register CA_REC *p ;
register SYMTAB *ip ;
{ static CELL dummy ;
switch( ip->type )
{
case ST_VAR :
p->type = CA_EXPR ;
code2(_PUSHI, ip->stval.cp) ;
break ;
case ST_LOCAL_VAR :
p->type = CA_EXPR ;
code1(L_PUSHI) ;
code1(ip->offset) ;
break ;
case ST_ARRAY :
p->type = CA_ARRAY ;
code2(A_PUSHA, ip->stval.array) ;
break ;
case ST_LOCAL_ARRAY :
p->type = CA_ARRAY ;
code1(LA_PUSHA) ;
code1(ip->offset) ;
break ;
/* not enough info to code it now; it will have to
be patched later */
case ST_NONE :
p->type = ST_NONE ;
p->call_offset = current_offset() ;
p->sym_p = ip ;
code2(_PUSHI, &dummy) ;
break ;
case ST_LOCAL_NONE :
p->type = ST_LOCAL_NONE ;
p->call_offset = current_offset() ;
p->type_p = & active_funct->typev[ip->offset] ;
code1(L_PUSHI) ;
code1(ip->offset) ;
break ;
#ifdef DEBUG
default :
bozo("code_call_id") ;
#endif
}
}
/* an RE by itself was coded as _MATCH0 , change to
push as an expression */
static void RE_as_arg()
{ CELL *cp = ZMALLOC(CELL) ;
code_ptr -= 2 ;
cp->type = C_RE ;
cp->ptr = code_ptr[1].ptr ;
code2(_PUSHC, cp) ;
}
int parse()
{ int yy = yyparse() ;
#if YYBYACC
extern struct yacc_mem *yacc_memp ;
yacc_memp++ ; /* puts parser tables in mem pool */
#endif
if ( resolve_list ) resolve_fcalls() ;
return yy ;
}