diff options
Diffstat (limited to 'filter/config.Y')
| -rw-r--r-- | filter/config.Y | 176 |
1 files changed, 125 insertions, 51 deletions
diff --git a/filter/config.Y b/filter/config.Y index 8cecf936..5ba4f7e6 100644 --- a/filter/config.Y +++ b/filter/config.Y @@ -32,6 +32,36 @@ static inline u32 pair_b(u32 p) { return p & 0xFFFF; } f_new_inst(FI_EA_SET, f_new_inst(fi_code, f_new_inst(FI_DEFAULT, f_new_inst(FI_EA_GET, da), f_new_inst(FI_CONSTANT, (struct f_val) { .type = T_INT, .val.i = def })), arg), da) +static int +f_new_var(struct sym_scope *s) +{ + /* + * - A variable is an offset on vstack from vbase. + * - Vbase is set on filter start / function call. + * - Scopes contain anonymous scopes (blocks) inside filter/function scope + * - Each scope knows number of vars in that scope + * - Offset is therefore a sum of 'slots' up to named scope + * - New variables are added on top of vstk, so intermediate values cannot + * be there during FI_VAR_INIT. I.e. no 'var' inside 'term'. + * - Also, each f_line must always have its scope, otherwise a variable may + * be defined but not initialized if relevant f_line is not executed. + */ + + int offset = s->slots++; + + while (!s->name) + { + s = s->next; + ASSERT(s); + offset += s->slots; + } + + if (offset >= 0xff) + cf_error("Too many variables, at most 255 allowed"); + + return offset; +} + /* * Sets and their items are during parsing handled as lists, linked * through left ptr. The first item in a list also contains a pointer @@ -276,7 +306,7 @@ assert_assign(struct f_lval *lval, struct f_inst *expr, const char *start, const checker = f_new_inst(FI_EQ, expr, getter); setter->next = checker; - + return assert_done(setter, start, end); } @@ -287,6 +317,7 @@ CF_KEYWORDS(FUNCTION, PRINT, PRINTN, UNSET, RETURN, INT, BOOL, IP, TYPE, PREFIX, RD, PAIR, QUAD, EC, LC, SET, STRING, BGPMASK, BGPPATH, CLIST, ECLIST, LCLIST, IF, THEN, ELSE, CASE, + FOR, IN, DO, TRUE, FALSE, RT, RO, UNKNOWN, GENERIC, FROM, GW, NET, MASK, PROTO, SCOPE, DEST, IFNAME, IFINDEX, WEIGHT, GW_MPLS, ROA_CHECK, ASN, SRC, DST, @@ -305,21 +336,23 @@ CF_KEYWORDS(FUNCTION, PRINT, PRINTN, UNSET, RETURN, %nonassoc ELSE %type <xp> cmds_int cmd_prep -%type <x> term block cmd cmds constant constructor print_list var_list function_call symbol_value bgp_path_expr bgp_path bgp_path_tail +%type <x> term cmd cmd_var cmds cmds_scoped constant constructor print_list var var_init var_list function_call symbol_value bgp_path_expr bgp_path bgp_path_tail %type <fsa> static_attr %type <fab> attr_bit %type <f> filter where_filter %type <fl> filter_body function_body %type <flv> lvalue -%type <i> type function_args function_vars +%type <i> type function_vars +%type <fa> function_argsn function_args %type <ecs> ec_kind -%type <fret> break_command +%type <fret> break_command %type <i32> cnum %type <e> pair_item ec_item lc_item set_item switch_item set_items switch_items switch_body %type <trie> fprefix_set %type <v> set_atom switch_atom fipa %type <px> fprefix %type <t> get_cf_position +%type <s> for_var CF_GRAMMAR @@ -343,7 +376,7 @@ filter_def: conf: filter_eval ; filter_eval: - EVAL term { f_eval_int(f_linearize($2)); } + EVAL term { f_eval_int(f_linearize($2, 1)); } ; conf: custom_attr ; @@ -425,25 +458,28 @@ type: ; function_argsn: - /* EMPTY */ + /* EMPTY */ { $$ = NULL; } | function_argsn type symbol ';' { if ($3->scope->slots >= 0xfe) cf_error("Too many declarations, at most 255 allowed"); - cf_define_symbol($3, SYM_VARIABLE | $2, offset, $3->scope->slots++); + $$ = cfg_alloc(sizeof(struct f_arg)); + $$->arg = cf_define_symbol($3, SYM_VARIABLE | $2, offset, sym_->scope->slots++); + $$->next = $1; } ; function_args: - '(' ')' { $$ = 0; } + '(' ')' { $$ = NULL; } | '(' function_argsn type symbol ')' { - cf_define_symbol($4, SYM_VARIABLE | $3, offset, $4->scope->slots++); - $$ = $4->scope->slots; + $$ = cfg_alloc(sizeof(struct f_arg)); + $$->arg = cf_define_symbol($4, SYM_VARIABLE | $3, offset, sym_->scope->slots++); + $$->next = $2; } ; function_vars: /* EMPTY */ { $$ = 0; } | function_vars type symbol ';' { - cf_define_symbol($3, SYM_VARIABLE | $2, offset, $3->scope->slots++); + cf_define_symbol($3, SYM_VARIABLE | $2, offset, f_new_var(sym_->scope)); $$ = $1 + 1; } ; @@ -471,20 +507,35 @@ where_filter: function_body: function_vars '{' cmds '}' { - $$ = f_linearize($3); + $$ = f_linearize($3, 0); $$->vars = $1; } ; conf: function_def ; function_def: - FUNCTION symbol { DBG( "Beginning of function %s\n", $2->name ); + FUNCTION symbol { + DBG( "Beginning of function %s\n", $2->name ); $2 = cf_define_symbol($2, SYM_FUNCTION, function, NULL); cf_push_scope($2); - } function_args function_body { - DBG("Definition of function %s with %u args and %u local vars.\n", $2->name, $4, $5->vars); - $5->args = $4; - $2->function = $5; + } function_args { + /* Make dummy f_line for storing function prototype */ + struct f_line *dummy = cfg_allocz(sizeof(struct f_line)); + $2->function = dummy; + + /* Revert the args */ + while ($4) { + struct f_arg *tmp = $4; + $4 = $4->next; + + tmp->next = dummy->arg_list; + dummy->arg_list = tmp; + dummy->args++; + } + } function_body { + $6->args = $2->function->args; + $6->arg_list = $2->function->arg_list; + $2->function = $6; cf_pop_scope(); } ; @@ -495,7 +546,11 @@ cmds: /* EMPTY */ { $$ = NULL; } | cmds_int { $$ = $1.begin; } ; -cmd_prep: cmd { +cmds_scoped: { cf_push_soft_scope(); } cmds { cf_pop_soft_scope(); $$ = $2; } ; + +cmd_var: var | cmd ; + +cmd_prep: cmd_var { $$.begin = $$.end = $1; if ($1) while ($$.end->next) @@ -517,15 +572,6 @@ cmds_int: cmd_prep } ; -block: - cmd { - $$=$1; - } - | '{' cmds '}' { - $$=$2; - } - ; - /* * Complex types, their bison value is struct f_val */ @@ -549,7 +595,7 @@ set_atom: | VPN_RD { $$.type = T_RD; $$.val.ec = $1; } | ENUM { $$.type = pair_a($1); $$.val.i = pair_b($1); } | '(' term ')' { - if (f_eval(f_linearize($2), &($$)) > F_RETURN) cf_error("Runtime error"); + if (f_eval(f_linearize($2, 1), &($$)) > F_RETURN) cf_error("Runtime error"); if (!f_valid_set_type($$.type)) cf_error("Set-incompatible type"); } | symbol_known { @@ -561,13 +607,13 @@ set_atom: switch_atom: NUM { $$.type = T_INT; $$.val.i = $1; } - | '(' term ')' { $$.type = T_INT; $$.val.i = f_eval_int(f_linearize($2)); } + | '(' term ')' { $$.type = T_INT; $$.val.i = f_eval_int(f_linearize($2, 1)); } | fipa { $$ = $1; } | ENUM { $$.type = pair_a($1); $$.val.i = pair_b($1); } ; cnum: - term { $$ = f_eval_int(f_linearize($1)); } + term { $$ = f_eval_int(f_linearize($1, 1)); } pair_item: '(' cnum ',' cnum ')' { $$ = f_new_pair_item($2, $2, $4, $4); } @@ -651,19 +697,19 @@ fprefix_set: ; switch_body: /* EMPTY */ { $$ = NULL; } - | switch_body switch_items ':' cmds { + | switch_body switch_items ':' cmds_scoped { /* Fill data fields */ struct f_tree *t; - struct f_line *line = f_linearize($4); + struct f_line *line = f_linearize($4, 0); for (t = $2; t; t = t->left) t->data = line; $$ = f_merge_items($1, $2); } - | switch_body ELSECOL cmds { + | switch_body ELSECOL cmds_scoped { struct f_tree *t = f_new_tree(); t->from.type = t->to.type = T_VOID; t->right = t; - t->data = f_linearize($3); + t->data = f_linearize($3, 0); $$ = f_merge_items($1, t); } ; @@ -680,6 +726,7 @@ bgp_path: bgp_path_tail: NUM bgp_path_tail { $$ = f_new_inst(FI_CONSTANT, (struct f_val) { .type = T_PATH_MASK_ITEM, .val.pmi = { .asn = $1, .kind = PM_ASN, }, }); $$->next = $2; } | NUM DDOT NUM bgp_path_tail { $$ = f_new_inst(FI_CONSTANT, (struct f_val) { .type = T_PATH_MASK_ITEM, .val.pmi = { .from = $1, .to = $3, .kind = PM_ASN_RANGE }, }); $$->next = $4; } + | '[' ']' bgp_path_tail { $$ = f_new_inst(FI_CONSTANT, (struct f_val) { .type = T_PATH_MASK_ITEM, .val.pmi = { .set = NULL, .kind = PM_ASN_SET }, }); $$->next = $3; } | '[' set_items ']' bgp_path_tail { if ($2->from.type != T_INT) cf_error("Only integer sets allowed in path mask"); $$ = f_new_inst(FI_CONSTANT, (struct f_val) { .type = T_PATH_MASK_ITEM, .val.pmi = { .set = build_tree($2), .kind = PM_ASN_SET }, }); $$->next = $4; @@ -699,6 +746,7 @@ constant: | fipa { $$ = f_new_inst(FI_CONSTANT, $1); } | VPN_RD { $$ = f_new_inst(FI_CONSTANT, (struct f_val) { .type = T_RD, .val.ec = $1, }); } | net_ { $$ = f_new_inst(FI_CONSTANT, (struct f_val) { .type = T_NET, .val.net = $1, }); } + | '[' ']' { $$ = f_new_inst(FI_CONSTANT, (struct f_val) { .type = T_SET, .val.t = NULL, }); } | '[' set_items ']' { DBG( "We've got a set here..." ); $$ = f_new_inst(FI_CONSTANT, (struct f_val) { .type = T_SET, .val.t = build_tree($2), }); @@ -722,27 +770,22 @@ var_list: /* EMPTY */ { $$ = NULL; } | var_list ',' term { $$ = $3; $$->next = $1; } function_call: - symbol_known '(' var_list ')' { + symbol_known '(' var_list ')' + { if ($1->class != SYM_FUNCTION) cf_error("You can't call something which is not a function. Really."); - struct f_inst *fc = f_new_inst(FI_CALL, $1); - uint args = 0; + /* Revert the var_list */ + struct f_inst *args = NULL; while ($3) { - args++; - struct f_inst *tmp = $3->next; - $3->next = fc; + struct f_inst *tmp = $3; + $3 = $3->next; - fc = $3; - $3 = tmp; + tmp->next = args; + args = tmp; } - if (args != $1->function->args) - cf_error("Function call '%s' got %u arguments, need %u arguments.", - $1->name, args, $1->function->args); - - $$ = f_new_inst(FI_CONSTANT, (struct f_val) { .type = T_VOID }); - $$->next = fc; + $$ = f_new_inst(FI_CALL, args, $1); } ; @@ -866,13 +909,44 @@ print_list: /* EMPTY */ { $$ = NULL; } } ; +var_init: + /* empty */ { $$ = f_new_inst(FI_CONSTANT, (struct f_val) { }); } + | '=' term { $$ = $2; } + ; + +var: + type symbol var_init ';' { + struct symbol *sym = cf_define_symbol($2, SYM_VARIABLE | $1, offset, f_new_var(sym_->scope)); + $$ = f_new_inst(FI_VAR_INIT, $3, sym); + } + +for_var: + type symbol { $$ = cf_define_symbol($2, SYM_VARIABLE | $1, offset, f_new_var(sym_->scope)); } + | CF_SYM_KNOWN { $$ = $1; cf_assert_symbol($1, SYM_VARIABLE); } + ; + cmd: - IF term THEN block { + '{' cmds_scoped '}' { + $$ = $2; + } + | IF term THEN cmd { $$ = f_new_inst(FI_CONDITION, $2, $4, NULL); } - | IF term THEN block ELSE block { + | IF term THEN cmd ELSE cmd { $$ = f_new_inst(FI_CONDITION, $2, $4, $6); } + | FOR { + /* Reserve space for walk data on stack */ + cf_push_scope(NULL); + conf_this_scope->slots += 2; + } for_var IN + /* Parse term in the parent scope */ + { conf_this_scope->active = 0; } term { conf_this_scope->active = 1; } + DO cmd { + cf_pop_scope(); + $$ = f_new_inst(FI_FOR_INIT, $6, $3); + $$->next = f_new_inst(FI_FOR_NEXT, $3, $9); + } | symbol_known '=' term ';' { switch ($1->class) { case SYM_VARIABLE_RANGE: @@ -929,7 +1003,7 @@ cmd: | PRINTN print_list ';' { $$ = f_new_inst(FI_PRINT, $2); } - | function_call ';' { $$ = f_new_inst(FI_DROP_RESULT, $1); } + | function_call ';' { $$ = f_new_inst(FI_DROP_RESULT, $1); } | CASE term '{' switch_body '}' { $$ = f_new_inst(FI_SWITCH, $2, build_tree($4)); } |