diff options
| author | Harald Welte <laforge@gnumonks.org> | 2011-02-19 13:29:34 +0100 |
|---|---|---|
| committer | Harald Welte <laforge@gnumonks.org> | 2011-02-19 13:29:34 +0100 |
| commit | 334493f3b253438a4393c9a470a091799c65578c (patch) | |
| tree | 54623c3a7fc3affb17b60ce39d264e0e6c8fd19f | |
| parent | 832889c5e76f27dd9ae556416bd7428081038464 (diff) | |
Enhance grammar with AST rewrite rules
It now generates a pretty meaningful AST representation of the
input data.
| -rw-r--r-- | osmo_codegen.g | 62 |
1 files changed, 48 insertions, 14 deletions
diff --git a/osmo_codegen.g b/osmo_codegen.g index 05a0335..68125e9 100644 --- a/osmo_codegen.g +++ b/osmo_codegen.g @@ -1,26 +1,44 @@ grammar osmo_codegen; -//options { +options { //language = Python; -//} + output = AST; +} +tokens { + PDUFIELD_OPT; + FIELD_VAL; + PDUFIELD_SIZE; + IEFIELD_ENDIAN; + IEFIELD_COND; + + IE_SPECS; + IE_ALIASES; + PDU_SPECS; +} + root : (pdu_spec | ie_spec | ie_alias)* + -> ^(IE_SPECS ie_spec*) ^(IE_ALIASES ie_alias*) ^(PDU_SPECS pdu_spec*) ; /* INFORMATION ELEMENTS */ /* An alias in the form "ie_alias new_name existing_field" */ -ie_alias: 'ie_alias' ie_name ie_name; +ie_alias: 'ie_alias' ie_name ie_name + -> ^(ie_name ie_name) + ; ie_name : ID; ie_spec : 'ie_spec' ID ie_field_def* 'end_ie_spec' + -> ^(ID ie_field_def*) ; ie_field_def - : ie_field_name ie_field_len ie_field_type ie_field_opts + : ie_field_name ie_field_len ie_field_type ie_field_opt* + -> ^(ie_field_name ie_field_type ie_field_len ie_field_opt*) ; ie_field_name @@ -34,16 +52,22 @@ ie_field_type | 'bit' | 'bits' | 'bcd' // BCD digits, always 'lower nibble, upper nibble, lower nibble, ... ); -ie_field_opts - : field_val? ie_field_cond? ie_field_endian?; +ie_field_opt + : (field_val | ie_field_cond | ie_field_endian) + ; ie_field_cond - : 'if (' ie_field_name ('&' ie_field_cond_mask)? COMP_OP ie_field_cond_reference ')'; + : 'if (' ie_field_name ('&' ie_field_cond_mask)? COMP_OP ie_field_cond_reference ')' + -> ^(IEFIELD_COND ie_field_name ie_field_cond_mask? COMP_OP ie_field_cond_reference) + ; ie_field_cond_mask : NUMERIC; ie_field_cond_reference : NUMERIC; ie_field_endian - : ('big' | 'little'); + : ( 'big' -> ^(IEFIELD_ENDIAN 'big') + | 'little' -> ^(IEFIELD_ENDIAN 'little') + ) + ; /* PDU DEFINITIONS*/ @@ -51,20 +75,26 @@ ie_field_endian pdu_spec : 'pdu_spec' ID pdu_field_def* - 'end_pdu_spec' + 'end_pdu_spec' -> ^(ID pdu_field_def*) ; pdu_field_mode : 'mand' | 'opt' | 'cond'; field_val - : ('val'|'value') NUMERIC; // Field always has to have indicated value + : ('val'|'value') NUMERIC // Field always has to have indicated value + -> ^(FIELD_VAL NUMERIC) + ; field_tag - : 'tag' NUMERIC; // for tagged fields + : 'tag' NUMERIC // for tagged fields + -> ^('tag' NUMERIC) + ; pdu_field_size - : NUMERIC ('-' NUMERIC)? ; // fixed length or range + : NUMERIC ('-' NUMERIC)? // fixed length or range + -> ^(PDUFIELD_SIZE NUMERIC*) + ; pdu_field_opts : pdu_up_downlink | pdu_opt_ie @@ -72,7 +102,9 @@ pdu_field_opts pdu_up_downlink : 'uplink_only' | 'downlink_only'; // only valid in uplink or downlink pdu_opt_ie - : 'ie' ID; // use speciifed IE definition + : 'ie' ID // use speciifed IE definition + -> ^('ie' ID) + ; pdu_field_type : ( @@ -87,7 +119,9 @@ pdu_field_type ) pdu_field_opts*; pdu_field_def - : ID pdu_field_mode pdu_field_type; + : ID pdu_field_mode pdu_field_type + -> ^(ID pdu_field_mode pdu_field_type) + ; /* LEXER RULES */ |