diff options
Diffstat (limited to 'bc/bc.y')
| -rw-r--r-- | bc/bc.y | 262 |
1 files changed, 195 insertions, 67 deletions
@@ -1,9 +1,6 @@ -%{ -/* bc.y: The grammar for a POSIX compatable bc processor with some - extensions to the language. */ - /* This file is part of GNU bc. - Copyright (C) 1991, 1992, 1993, 1994, 1997 Free Software Foundation, Inc. + + Copyright (C) 1991-1994, 1997, 2006 Free Software Foundation, Inc. This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by @@ -18,8 +15,8 @@ You should have received a copy of the GNU General Public License along with this program; see the file COPYING. If not, write to: The Free Software Foundation, Inc. - 59 Temple Place, Suite 330 - Boston, MA 02111 USA + Foundation, Inc. 51 Franklin Street, Fifth Floor, + Boston, MA 02110-1301 USA You may contact the author by: e-mail: philnelson@acm.org @@ -30,9 +27,26 @@ *************************************************************************/ +/* bc.y: The grammar for a POSIX compatable bc processor with some + extensions to the language. */ + +%{ + #include "bcdefs.h" #include "global.h" #include "proto.h" + +/* current function number. */ +int cur_func = -1; + +/* Expression encoded information -- See comment at expression rules. */ +#define EX_ASSGN 0 +#define EX_REG 1 +#define EX_COMP 2 +#define EX_PAREN 4 +#define EX_VOID 8 +#define EX_EMPTY 16 + %} %start program @@ -76,12 +90,13 @@ %token <i_value> Define Break Quit Length /* 'return', 'for', 'if', 'while', 'sqrt', 'else' */ %token <i_value> Return For If While Sqrt Else -/* 'scale', 'ibase', 'obase', 'auto', 'read' */ -%token <i_value> Scale Ibase Obase Auto Read +/* 'scale', 'ibase', 'obase', 'auto', 'read', 'random' */ +%token <i_value> Scale Ibase Obase Auto Read Random /* 'warranty', 'halt', 'last', 'continue', 'print', 'limits' */ -%token <i_value> Warranty, Halt, Last, Continue, Print, Limits -/* 'history' */ -%token <i_value> UNARY_MINUS HistoryVar +%token <i_value> Warranty Halt Last Continue Print Limits +/* 'history', 'void' */ +%token <i_value> UNARY_MINUS HistoryVar Void + /* Types of all other things. */ %type <i_value> expression return_expression named_expression opt_expression @@ -90,6 +105,7 @@ %type <a_value> opt_argument_list argument_list %type <i_value> program input_item semicolon_list statement_list %type <i_value> statement function statement_or_error required_eol +%type <i_value> opt_void /* precedence */ %left OR @@ -153,9 +169,9 @@ statement : Warranty { limits (); } | expression { - if ($1 & 2) + if ($1 & EX_COMP) warn ("comparison in expression"); - if ($1 & 1) + if ($1 & EX_REG) generate ("W"); else generate ("p"); @@ -201,9 +217,11 @@ statement : Warranty } '(' opt_expression ';' { - if ($4 & 2) + if ($4 & EX_COMP) warn ("Comparison in first for expression"); - if ($4 >= 0) + if ($4 & EX_VOID) + yyerror ("first expression is void"); + if (!($4 & EX_EMPTY)) generate ("p"); $4 = next_label++; sprintf (genstr, "N%1d:", $4); @@ -211,7 +229,9 @@ statement : Warranty } opt_expression ';' { - if ($7 < 0) generate ("1"); + if ($7 & EX_VOID) + yyerror ("second expression is void"); + if ($7 & EX_EMPTY ) generate ("1"); $7 = next_label++; sprintf (genstr, "B%1d:J%1d:", $7, break_label); generate (genstr); @@ -222,9 +242,11 @@ statement : Warranty } opt_expression ')' { - if ($10 & 2 ) + if ($10 & EX_COMP) warn ("Comparison in third for expression"); - if ($10 & 16) + if ($10 & EX_VOID) + yyerror ("third expression is void"); + if ($10 & EX_EMPTY) sprintf (genstr, "J%1d:N%1d:", $4, $7); else sprintf (genstr, "pJ%1d:N%1d:", $4, $7); @@ -240,6 +262,8 @@ statement : Warranty } | If '(' expression ')' { + if ($3 & EX_VOID) + yyerror ("void expression"); $3 = if_label; if_label = next_label++; sprintf (genstr, "Z%1d:", if_label); @@ -259,6 +283,8 @@ statement : Warranty } '(' expression { + if ($4 & EX_VOID) + yyerror ("void expression"); $4 = break_label; break_label = next_label++; sprintf (genstr, "Z%1d:", break_label); @@ -286,7 +312,11 @@ print_element : STRING free ($1); } | expression - { generate ("P"); } + { + if ($1 & EX_VOID) + yyerror ("void expression in print"); + generate ("P"); + } ; opt_else : /* nothing */ | Else @@ -298,17 +328,23 @@ opt_else : /* nothing */ if_label = $1; } opt_newline statement -function : Define NAME '(' opt_parameter_list ')' opt_newline + ; +function : Define opt_void NAME '(' opt_parameter_list ')' opt_newline '{' required_eol opt_auto_define_list - { + { char *params, *autos; /* Check auto list against parameter list? */ - check_params ($4,$9); - sprintf (genstr, "F%d,%s.%s[", - lookup($2,FUNCTDEF), - arg_str ($4), arg_str ($9)); + check_params ($5,$10); + params = arg_str ($5); + autos = arg_str ($10); + set_genstr_size (30 + strlen (params) + + strlen (autos)); + cur_func = lookup($3,FUNCTDEF); + sprintf (genstr, "F%d,%s.%s[", cur_func, params, + autos); generate (genstr); - free_args ($4); - free_args ($9); + functions[cur_func].f_void = $2; + free_args ($5); + free_args ($10); $1 = next_label; next_label = 1; } @@ -316,6 +352,15 @@ function : Define NAME '(' opt_parameter_list ')' opt_newline { generate ("0R]"); next_label = $1; + cur_func = -1; + } + ; +opt_void : /* empty */ + { $$ = 0; } + | Void + { + $$ = 1; + warn ("void functions"); } ; opt_parameter_list : /* empty */ @@ -334,13 +379,25 @@ define_list : NAME | NAME '[' ']' { $$ = nextarg (NULL, lookup ($1,ARRAY), FALSE); } | '*' NAME '[' ']' - { $$ = nextarg (NULL, lookup ($2,ARRAY), TRUE); } + { $$ = nextarg (NULL, lookup ($2,ARRAY), TRUE); + warn ("Call by variable arrays"); + } + | '&' NAME '[' ']' + { $$ = nextarg (NULL, lookup ($2,ARRAY), TRUE); + warn ("Call by variable arrays"); + } | define_list ',' NAME { $$ = nextarg ($1, lookup ($3,SIMPLE), FALSE); } | define_list ',' NAME '[' ']' { $$ = nextarg ($1, lookup ($3,ARRAY), FALSE); } | define_list ',' '*' NAME '[' ']' - { $$ = nextarg ($1, lookup ($4,ARRAY), TRUE); } + { $$ = nextarg ($1, lookup ($4,ARRAY), TRUE); + warn ("Call by variable arrays"); + } + | define_list ',' '&' NAME '[' ']' + { $$ = nextarg ($1, lookup ($4,ARRAY), TRUE); + warn ("Call by variable arrays"); + } ; opt_argument_list : /* empty */ { $$ = NULL; } @@ -348,7 +405,10 @@ opt_argument_list : /* empty */ ; argument_list : expression { - if ($1 & 2) warn ("comparison in argument"); + if ($1 & EX_COMP) + warn ("comparison in argument"); + if ($1 & EX_VOID) + yyerror ("void argument"); $$ = nextarg (NULL,0,FALSE); } | NAME '[' ']' @@ -359,7 +419,10 @@ argument_list : expression } | argument_list ',' expression { - if ($3 & 2) warn ("comparison in argument"); + if ($3 & EX_COMP) + warn ("comparison in argument"); + if ($3 & EX_VOID) + yyerror ("void argument"); $$ = nextarg ($1,0,FALSE); } | argument_list ',' NAME '[' ']' @@ -370,17 +433,18 @@ argument_list : expression } ; -/* Expression lval meanings! (Bits mean something!) +/* Expression lval meanings! (Bits mean something!) (See defines above) * 0 => Top op is assignment. * 1 => Top op is not assignment. * 2 => Comparison is somewhere in expression. * 4 => Expression is in parenthesis. + * 8 => Expression is void! * 16 => Empty optional expression. */ opt_expression : /* empty */ { - $$ = 16; + $$ = EX_EMPTY; warn ("Missing expression in for statement"); } | expression @@ -389,13 +453,21 @@ return_expression : /* empty */ { $$ = 0; generate ("0"); + if (cur_func == -1) + yyerror("Return outside of a function."); } | expression { - if ($1 & 2) + if ($1 & EX_COMP) warn ("comparison in return expresion"); - if (!($1 & 4)) + if (!($1 & EX_PAREN)) warn ("return expression requires parenthesis"); + if ($1 & EX_VOID) + yyerror("return requires non-void expression"); + if (cur_func == -1) + yyerror("Return outside of a function."); + else if (functions[cur_func].f_void) + yyerror("Return expression in a void function."); } ; expression : named_expression ASSIGN_OP @@ -411,7 +483,10 @@ expression : named_expression ASSIGN_OP } expression { - if ($4 & 2) warn("comparison in assignment"); + if ($4 & EX_ASSGN) + warn("comparison in assignment"); + if ($4 & EX_VOID) + yyerror("Assignment of a void expression"); if ($2 != '=') { sprintf (genstr, "%c", $2); @@ -422,9 +497,8 @@ expression : named_expression ASSIGN_OP else sprintf (genstr, "s%d:", $1); generate (genstr); - $$ = 0; + $$ = EX_ASSGN; } - ; | expression AND { warn("&& operator"); @@ -434,9 +508,11 @@ expression : named_expression ASSIGN_OP } expression { + if (($1 & EX_VOID) || ($4 & EX_VOID)) + yyerror ("void expression with &&"); sprintf (genstr, "DZ%d:p1N%d:", $2, $2); generate (genstr); - $$ = ($1 | $4) & ~4; + $$ = ($1 | $4) & ~EX_PAREN; } | expression OR { @@ -448,21 +524,27 @@ expression : named_expression ASSIGN_OP expression { int tmplab; + if (($1 & EX_VOID) || ($4 & EX_VOID)) + yyerror ("void expression with ||"); tmplab = next_label++; sprintf (genstr, "B%d:0J%d:N%d:1N%d:", $2, tmplab, $2, tmplab); generate (genstr); - $$ = ($1 | $4) & ~4; + $$ = ($1 | $4) & ~EX_PAREN; } | NOT expression { - $$ = $2 & ~4; + if ($2 & EX_VOID) + yyerror ("void expression with !"); + $$ = $2 & ~EX_PAREN; warn("! operator"); generate ("!"); } | expression REL_OP expression { - $$ = 3; + if (($1 & EX_VOID) || ($3 & EX_VOID)) + yyerror ("void expression with comparison"); + $$ = EX_REG | EX_COMP; switch (*($2)) { case '=': @@ -490,42 +572,56 @@ expression : named_expression ASSIGN_OP } | expression '+' expression { + if (($1 & EX_VOID) || ($3 & EX_VOID)) + yyerror ("void expression with +"); generate ("+"); - $$ = ($1 | $3) & ~4; + $$ = ($1 | $3) & ~EX_PAREN; } | expression '-' expression { + if (($1 & EX_VOID) || ($3 & EX_VOID)) + yyerror ("void expression with -"); generate ("-"); - $$ = ($1 | $3) & ~4; + $$ = ($1 | $3) & ~EX_PAREN; } | expression '*' expression { + if (($1 & EX_VOID) || ($3 & EX_VOID)) + yyerror ("void expression with *"); generate ("*"); - $$ = ($1 | $3) & ~4; + $$ = ($1 | $3) & ~EX_PAREN; } | expression '/' expression { + if (($1 & EX_VOID) || ($3 & EX_VOID)) + yyerror ("void expression with /"); generate ("/"); - $$ = ($1 | $3) & ~4; + $$ = ($1 | $3) & ~EX_PAREN; } | expression '%' expression { + if (($1 & EX_VOID) || ($3 & EX_VOID)) + yyerror ("void expression with %"); generate ("%"); - $$ = ($1 | $3) & ~4; + $$ = ($1 | $3) & ~EX_PAREN; } | expression '^' expression { + if (($1 & EX_VOID) || ($3 & EX_VOID)) + yyerror ("void expression with ^"); generate ("^"); - $$ = ($1 | $3) & ~4; + $$ = ($1 | $3) & ~EX_PAREN; } | '-' expression %prec UNARY_MINUS { + if ($2 & EX_VOID) + yyerror ("void expression with unary -"); generate ("n"); - $$ = $2 & ~4; + $$ = $2 & ~EX_PAREN; } | named_expression { - $$ = 1; + $$ = EX_REG; if ($1 < 0) sprintf (genstr, "L%d:", -$1); else @@ -535,7 +631,7 @@ expression : named_expression ASSIGN_OP | NUMBER { int len = strlen($1); - $$ = 1; + $$ = EX_REG; if (len == 1 && *$1 == '0') generate ("0"); else if (len == 1 && *$1 == '1') @@ -549,26 +645,33 @@ expression : named_expression ASSIGN_OP free ($1); } | '(' expression ')' - { $$ = $2 | 5; } + { + if ($2 & EX_VOID) + yyerror ("void expression in parenthesis"); + $$ = $2 | EX_REG | EX_PAREN; + } | NAME '(' opt_argument_list ')' - { - $$ = 1; + { int fn; + fn = lookup ($1,FUNCT); + if (functions[fn].f_void) + $$ = EX_VOID; + else + $$ = EX_REG; if ($3 != NULL) - { - sprintf (genstr, "C%d,%s:", - lookup ($1,FUNCT), - call_str ($3)); + { char *params = call_str ($3); + set_genstr_size (20 + strlen (params)); + sprintf (genstr, "C%d,%s:", fn, params); free_args ($3); } else { - sprintf (genstr, "C%d:", lookup ($1,FUNCT)); + sprintf (genstr, "C%d:", fn); } generate (genstr); } | INCR_DECR named_expression { - $$ = 1; + $$ = EX_REG; if ($2 < 0) { if ($1 == '+') @@ -587,7 +690,7 @@ expression : named_expression ASSIGN_OP } | named_expression INCR_DECR { - $$ = 1; + $$ = EX_REG; if ($1 < 0) { sprintf (genstr, "DL%d:x", -$1); @@ -609,22 +712,47 @@ expression : named_expression ASSIGN_OP generate (genstr); } | Length '(' expression ')' - { generate ("cL"); $$ = 1;} + { + if ($3 & EX_VOID) + yyerror ("void expression in length()"); + generate ("cL"); + $$ = EX_REG; + } | Sqrt '(' expression ')' - { generate ("cR"); $$ = 1;} + { + if ($3 & EX_VOID) + yyerror ("void expression in sqrt()"); + generate ("cR"); + $$ = EX_REG; + } | Scale '(' expression ')' - { generate ("cS"); $$ = 1;} + { + if ($3 & EX_VOID) + yyerror ("void expression in scale()"); + generate ("cS"); + $$ = EX_REG; + } | Read '(' ')' { warn ("read function"); - generate ("cI"); $$ = 1; + generate ("cI"); + $$ = EX_REG; + } + | Random '(' ')' + { + warn ("random function"); + generate ("cX"); + $$ = EX_REG; } ; named_expression : NAME { $$ = lookup($1,SIMPLE); } | NAME '[' expression ']' { - if ($3 > 1) warn("comparison in subscript"); + if ($3 & EX_VOID) + yyerror("void expression as subscript"); + if ($3 & EX_COMP) + warn("comparison in subscript"); $$ = lookup($1,ARRAY); } | Ibase |