diff options
| -rw-r--r-- | doc/bird.sgml | 26 | ||||
| -rw-r--r-- | filter/config.Y | 21 | ||||
| -rw-r--r-- | filter/data.c | 1 | ||||
| -rw-r--r-- | filter/f-inst.c | 93 | ||||
| -rw-r--r-- | filter/test.conf | 40 | ||||
| -rw-r--r-- | nest/a-path.c | 29 | ||||
| -rw-r--r-- | nest/a-set.c | 48 | ||||
| -rw-r--r-- | nest/attrs.h | 4 |
8 files changed, 254 insertions, 8 deletions
diff --git a/doc/bird.sgml b/doc/bird.sgml index f933128c..89b1541c 100644 --- a/doc/bird.sgml +++ b/doc/bird.sgml @@ -1683,7 +1683,8 @@ prefix and an ASN as arguments. <sect>Control structures <label id="control-structures"> -<p>Filters support two control structures: conditions and case switches. +<p>Filters support several control structures: conditions, for loops and case +switches. <p>Syntax of a condition is: <cf>if <M>boolean expression</M> then <m/commandT/; else <m/commandF/;</cf> and you can use <cf>{ <m/command1/; <m/command2/; @@ -1691,6 +1692,14 @@ else <m/commandF/;</cf> and you can use <cf>{ <m/command1/; <m/command2/; omitted. If the <cf><m>boolean expression</m></cf> is true, <m/commandT/ is executed, otherwise <m/commandF/ is executed. +<p>For loops allow to iterate over elements in compound data like BGP paths or +community lists. The syntax is: <cf>for [ <m/type/ ] <m/variable/ in <m/expr/ +do <m/command/;</cf> and you can also use compound command like in conditions. +The expression is evaluated to a compound data, then for each element from such +data the command is executed with the item assigned to the variable. A variable +may be an existing one (when just name is used) or a locally defined (when type +and name is used). In both cases, it must have the same type as elements. + <p>The <cf>case</cf> is similar to case from Pascal. Syntax is <cf>case <m/expr/ { else: | <m/num_or_prefix [ .. num_or_prefix]/: <m/statement/ ; [ ... ] }</cf>. The expression after <cf>case</cf> can be of any type which can be @@ -1703,16 +1712,21 @@ neither of the <cf/:/ clauses, the statements after <cf/else:/ are executed. <p>Here is example that uses <cf/if/ and <cf/case/ structures: <code> +if 1234 = i then printn "."; else { + print "not 1234"; + print "You need {} around multiple commands"; +} + +for int asn in bgp_path do { + printn "ASN: ", asn; + if asn < 65536 then print " (2B)"; else print " (4B)"; +} + case arg1 { 2: print "two"; print "I can do more commands without {}"; 3 .. 5: print "three to five"; else: print "something else"; } - -if 1234 = i then printn "."; else { - print "not 1234"; - print "You need {} around multiple commands"; -} </code> diff --git a/filter/config.Y b/filter/config.Y index f8f47862..c7c82068 100644 --- a/filter/config.Y +++ b/filter/config.Y @@ -296,7 +296,7 @@ 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); } @@ -307,6 +307,7 @@ 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, SOURCE, SCOPE, DEST, IFNAME, IFINDEX, WEIGHT, GW_MPLS, PREFERENCE, @@ -342,6 +343,7 @@ CF_KEYWORDS(FUNCTION, PRINT, PRINTN, UNSET, RETURN, %type <v> set_atom switch_atom fipa %type <px> fprefix %type <t> get_cf_position +%type <s> for_var CF_GRAMMAR @@ -899,6 +901,11 @@ var: $$ = f_new_inst(FI_VAR_INIT, $3, sym); } +for_var: + type symbol { $$ = cf_define_symbol($2, SYM_VARIABLE | $1, offset, f_new_var(sym_->scope)); } + | CF_SYM_KNOWN { $$ = $1; cf_assert_symbol($1, SYM_VARIABLE); } + ; + cmd: '{' cmds_scoped '}' { $$ = $2; @@ -909,6 +916,18 @@ cmd: | 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); + } | CF_SYM_KNOWN '=' term ';' { switch ($1->class) { case SYM_VARIABLE_RANGE: diff --git a/filter/data.c b/filter/data.c index 2bb5920c..87c438fc 100644 --- a/filter/data.c +++ b/filter/data.c @@ -72,6 +72,7 @@ enum f_type f_type_element_type(enum f_type t) { switch(t) { + case T_PATH: return T_INT; case T_CLIST: return T_PAIR; case T_ECLIST: return T_EC; case T_LCLIST: return T_LC; diff --git a/filter/f-inst.c b/filter/f-inst.c index dc243b4e..30db96f2 100644 --- a/filter/f-inst.c +++ b/filter/f-inst.c @@ -87,6 +87,11 @@ * m4_dnl RESULT_VOID; return undef * m4_dnl } * + * Note that runtime arguments m4_dnl (ARG*, VARARG) must be defined before + * parse-time arguments m4_dnl (LINE, SYMBOL, ...). During linearization, + * first ones move position in f_line by linearizing arguments first, while + * second ones store data to the current position. + * * Also note that the { ... } blocks are not respected by M4 at all. * If you get weird unmatched-brace-pair errors, check what it generated and why. * What is really considered as one instruction is not the { ... } block @@ -543,6 +548,94 @@ RESULT_VAL(val); } + INST(FI_FOR_INIT, 1, 0) { + NEVER_CONSTANT; + ARG_ANY(1); + SYMBOL; + + FID_NEW_BODY() + ASSERT((sym->class & ~0xff) == SYM_VARIABLE); + + /* Static type check */ + if (f1->type) + { + enum f_type t_var = (sym->class & 0xff); + enum f_type t_arg = f_type_element_type(f1->type); + if (!t_arg) + cf_error("Value of expression in FOR must be iterable, got %s", + f_type_name(f1->type)); + if (t_var != t_arg) + cf_error("Loop variable '%s' in FOR must be %s, is %s", + sym->name, f_type_name(t_arg), f_type_name(t_var)); + } + + FID_INTERPRET_BODY() + + /* Dynamic type check */ + if ((sym->class & 0xff) != f_type_element_type(v1.type)) + runtime("Mismatched argument and variable type"); + + /* Setup the index */ + v2 = (struct f_val) { .type = T_INT, .val.i = 0 }; + + /* Keep v1 and v2 on the stack */ + fstk->vcnt += 2; + } + + INST(FI_FOR_NEXT, 2, 0) { + NEVER_CONSTANT; + SYMBOL; + + /* Type checks are done in FI_FOR_INIT */ + + /* Loop variable */ + struct f_val *var = &fstk->vstk[curline.vbase + sym->offset]; + int step = 0; + + switch(v1.type) + { + case T_PATH: + var->type = T_INT; + step = as_path_walk(v1.val.ad, &v2.val.i, &var->val.i); + break; + + case T_CLIST: + var->type = T_PAIR; + step = int_set_walk(v1.val.ad, &v2.val.i, &var->val.i); + break; + + case T_ECLIST: + var->type = T_EC; + step = ec_set_walk(v1.val.ad, &v2.val.i, &var->val.ec); + break; + + case T_LCLIST: + var->type = T_LC; + step = lc_set_walk(v1.val.ad, &v2.val.i, &var->val.lc); + break; + + default: + runtime( "Clist or lclist expected" ); + } + + if (step) + { + /* Keep v1 and v2 on the stack */ + fstk->vcnt += 2; + + /* Repeat this instruction */ + curline.pos--; + + /* Execute the loop body */ + LINE(1, 0); + + /* Space for loop variable, may be unused */ + fstk->vcnt += 1; + } + else + var->type = T_VOID; + } + INST(FI_CONDITION, 1, 0) { ARG(1, T_BOOL); if (v1.val.i) diff --git a/filter/test.conf b/filter/test.conf index 436031a3..bc5f898e 100644 --- a/filter/test.conf +++ b/filter/test.conf @@ -758,6 +758,15 @@ int set set12; bt_assert(delete(p2, [4..5]) = prepend(prepend(prepend(prepend(+empty+, 3), 3), 2), 1)); bt_assert(format([= 1 2+ 3 =]) = "[= 1 2 + 3 =]"); + + # iteration over path + int x = 0; + int y = 0; + for int i in p2 do { + x = x + i; + y = y + x; + } + bt_assert(x = 18 && y = 50); } bt_test_suite(t_path, "Testing paths"); @@ -884,6 +893,12 @@ clist r; bt_assert(format(r) = "(clist (2,1) (1,3) (2,2) (3,1) (2,3))"); bt_assert(r.min = (1,3)); bt_assert(r.max = (3,1)); + + # iteration over clist + int x = 0; + for pair c in r do + x = x + c.asn * c.asn * c.data; + bt_assert(x = 36); } bt_test_suite(t_clist, "Testing lists of communities"); @@ -999,6 +1014,13 @@ eclist r; bt_assert(format(r) = "(eclist (rt, 2, 1) (rt, 1, 3) (rt, 2, 2) (rt, 3, 1) (rt, 2, 3))"); bt_assert(r.min = (rt, 1, 3)); bt_assert(r.max = (rt, 3, 1)); + + # iteration over eclist + int x = 0; + for ec c in r do + if c > (rt, 2, 0) && c < (rt, 3, 0) then + x = x + 1; + bt_assert(x = 3); } bt_test_suite(t_eclist, "Testing lists of extended communities"); @@ -1117,6 +1139,19 @@ lclist r; bt_assert(format(r) = "(lclist (2, 3, 3) (1, 2, 3) (2, 3, 1) (3, 1, 2) (2, 1, 3))"); bt_assert(r.min = (1, 2, 3)); bt_assert(r.max = (3, 1, 2)); + + # iteration over lclist + int x = 0; + int y = 0; + lc mx = (0, 0, 0); + for lc c in r do { + int asn2 = c.asn * c.asn; + x = x + asn2 * c.data1; + y = y + asn2 * c.data2; + if c > mx then mx = c; + } + bt_assert(x = 39 && y = 49); + bt_assert(mx = r.max); } bt_test_suite(t_lclist, "Testing lists of large communities"); @@ -1580,13 +1615,16 @@ filter vpn_filter bt_assert(net.type != NET_IP6); bt_assert(net.rd = 0:1:2); + bool b = false; case (net.type) { NET_IP4: print "IPV4"; NET_IP6: print "IPV6"; + else: b = true; } + bt_assert(b); bt_check_assign(from, 10.20.30.40); - bt_check_assign(gw, 55.55.55.44); + # bt_check_assign(gw, 55.55.55.44); bgp_community.add((3,5)); bgp_ext_community.add((ro, 135, 999)); diff --git a/nest/a-path.c b/nest/a-path.c index d5b01635..6bb18285 100644 --- a/nest/a-path.c +++ b/nest/a-path.c @@ -669,6 +669,35 @@ as_path_filter(struct linpool *pool, const struct adata *path, const struct f_va return res; } +int +as_path_walk(const struct adata *path, uint *pos, uint *val) +{ + if (!path) + return 0; + + const u8 *p = path->data; + const u8 *q = p + path->length; + uint n, x = *pos; + + while (p < q) + { + n = p[1]; + p += 2; + + if (x < n) + { + *val = get_as(p + x * BS); + *pos += 1; + return 1; + } + + p += n * BS; + x -= n; + } + + return 0; +} + struct pm_pos { diff --git a/nest/a-set.c b/nest/a-set.c index 71fbac94..40ed573c 100644 --- a/nest/a-set.c +++ b/nest/a-set.c @@ -693,3 +693,51 @@ lc_set_max(const struct adata *list, lcomm *val) *val = (lcomm) { res[0], res[1], res[2] }; return 1; } + +int +int_set_walk(const struct adata *list, uint *pos, uint *val) +{ + if (!list) + return 0; + + if (*pos >= (uint) int_set_get_size(list)) + return 0; + + u32 *res = int_set_get_data(list) + *pos; + *val = *res; + *pos += 1; + + return 1; +} + +int +ec_set_walk(const struct adata *list, uint *pos, u64 *val) +{ + if (!list) + return 0; + + if (*pos >= (uint) int_set_get_size(list)) + return 0; + + u32 *res = int_set_get_data(list) + *pos; + *val = ec_generic(res[0], res[1]); + *pos += 2; + + return 1; +} + +int +lc_set_walk(const struct adata *list, uint *pos, lcomm *val) +{ + if (!list) + return 0; + + if (*pos >= (uint) int_set_get_size(list)) + return 0; + + u32 *res = int_set_get_data(list) + *pos; + *val = (lcomm) { res[0], res[1], res[2] }; + *pos += 3; + + return 1; +} diff --git a/nest/attrs.h b/nest/attrs.h index 22e2ff4a..9412439b 100644 --- a/nest/attrs.h +++ b/nest/attrs.h @@ -51,6 +51,7 @@ u32 as_path_get_last_nonaggregated(const struct adata *path); int as_path_contains(const struct adata *path, u32 as, int min); int as_path_match_set(const struct adata *path, const struct f_tree *set); const struct adata *as_path_filter(struct linpool *pool, const struct adata *path, const struct f_val *set, int pos); +int as_path_walk(const struct adata *path, uint *pos, uint *val); static inline struct adata *as_path_prepend(struct linpool *pool, const struct adata *path, u32 as) { return as_path_prepend2(pool, path, AS_PATH_SEQUENCE, as); } @@ -225,6 +226,9 @@ int lc_set_min(const struct adata *list, lcomm *val); int int_set_max(const struct adata *list, u32 *val); int ec_set_max(const struct adata *list, u64 *val); int lc_set_max(const struct adata *list, lcomm *val); +int int_set_walk(const struct adata *list, uint *pos, u32 *val); +int ec_set_walk(const struct adata *list, uint *pos, u64 *val); +int lc_set_walk(const struct adata *list, uint *pos, lcomm *val); void ec_set_sort_x(struct adata *set); /* Sort in place */ |