diff options
Diffstat (limited to 'vpp/vlib/vlib/lex.c')
| -rw-r--r-- | vpp/vlib/vlib/lex.c | 271 |
1 files changed, 271 insertions, 0 deletions
diff --git a/vpp/vlib/vlib/lex.c b/vpp/vlib/vlib/lex.c new file mode 100644 index 00000000..1cc8f167 --- /dev/null +++ b/vpp/vlib/vlib/lex.c @@ -0,0 +1,271 @@ +/* + * Copyright (c) 2015 Cisco and/or its affiliates. + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at: + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ +#include <vlib/vlib.h> +#include <vlib/lex.h> + +vlib_lex_main_t vlib_lex_main; + +#define LEX_DEBUG 0 + +u8 * +format_vlib_lex_token (u8 * s, va_list * args) +{ + vlib_lex_main_t *lm = va_arg (*args, vlib_lex_main_t *); + vlib_lex_token_t *t = va_arg (*args, vlib_lex_token_t *); + + if (t->token == VLIB_LEX_word) + s = format (s, "%s", t->value.as_pointer); + else + s = format (s, "%s", lm->lex_token_names[t->token]); + return s; +} + +void +vlib_lex_get_token (vlib_lex_main_t * lm, vlib_lex_token_t * rv) +{ + u8 c; + vlib_lex_table_t *t; + vlib_lex_table_entry_t *e; + uword tv; + + if (PREDICT_FALSE (lm->pushback_sp >= 0)) + { + rv[0] = lm->pushback_vector[lm->pushback_sp--]; + return; + } + + rv->value.as_uword = ~0; + + while (1) + { + if (PREDICT_FALSE (lm->current_index >= vec_len (lm->input_vector))) + { + rv->token = VLIB_LEX_eof; + return; + } + + t = vec_elt_at_index (lm->lex_tables, lm->current_table_index); + c = (lm->input_vector[lm->current_index++]) & 0x7f; + e = &t->entries[c]; + lm->current_table_index = e->next_table_index; + + switch (e->action) + { + case VLIB_LEX_IGNORE: + continue; + + case VLIB_LEX_START_NUMBER: + lm->current_token_value = 0; + /* fallthru */ + + case VLIB_LEX_ADD_TO_NUMBER: + lm->current_number_base = e->token; + lm->current_token_value *= lm->current_number_base; + tv = c - '0'; + if (tv >= lm->current_number_base) + { + tv = 10 + c - 'A'; + if (tv >= lm->current_number_base) + tv = 10 + c - 'a'; + } + lm->current_token_value += tv; + continue; + + case VLIB_LEX_ADD_TO_TOKEN: + vec_add1 (lm->token_buffer, c); + continue; + + case VLIB_LEX_KEYWORD_CHECK: + { + uword *p; + + vec_add1 (lm->token_buffer, 0); + + /* It's either a keyword or just a word. */ + p = hash_get_mem (lm->lex_keywords, lm->token_buffer); + if (p) + { + rv->token = p[0]; + if (LEX_DEBUG > 0) + clib_warning ("keyword '%s' token %s", + lm->token_buffer, + lm->lex_token_names[rv->token]); + } + else + { + /* it's a WORD */ + rv->token = VLIB_LEX_word; + rv->value.as_pointer = vec_dup (lm->token_buffer); + if (LEX_DEBUG > 0) + clib_warning ("%s, value '%s'", + lm->lex_token_names[VLIB_LEX_word], + rv->value.as_pointer); + } + _vec_len (lm->token_buffer) = 0; + + /* Rescan the character which terminated the keyword/word. */ + lm->current_index--; + return; + } + + case VLIB_LEX_RETURN_AND_RESCAN: + ASSERT (lm->current_index); + lm->current_index--; + /* note flow-through */ + + case VLIB_LEX_RETURN: + rv->token = e->token; + rv->value.as_uword = lm->current_token_value; + lm->current_token_value = ~0; + if (LEX_DEBUG > 0) + { + clib_warning + ("table %s char '%c'(0x%02x) next table %s return %s", + t->name, c, c, lm->lex_tables[e->next_table_index].name, + lm->lex_token_names[e->token]); + if (rv->token == VLIB_LEX_number) + clib_warning (" numeric value 0x%x (%d)", rv->value, + rv->value); + } + return; + } + } +} + +u16 +vlib_lex_add_token (vlib_lex_main_t * lm, char *token_name) +{ + uword *p; + u16 rv; + + p = hash_get_mem (lm->lex_tokens_by_name, token_name); + + if (p) + return p[0]; + + rv = vec_len (lm->lex_token_names); + hash_set_mem (lm->lex_tokens_by_name, token_name, rv); + vec_add1 (lm->lex_token_names, token_name); + + return rv; +} + +static u16 +add_keyword (vlib_lex_main_t * lm, char *keyword, char *token_name) +{ + uword *p; + u16 token; + + p = hash_get_mem (lm->lex_keywords, keyword); + + ASSERT (p == 0); + + token = vlib_lex_add_token (lm, token_name); + + hash_set_mem (lm->lex_keywords, keyword, token); + return token; +} + +u16 +vlib_lex_find_or_add_keyword (vlib_lex_main_t * lm, char *keyword, + char *token_name) +{ + uword *p = hash_get_mem (lm->lex_keywords, keyword); + return p ? p[0] : add_keyword (lm, keyword, token_name); +} + +void +vlib_lex_set_action_range (u32 table_index, u8 lo, u8 hi, u16 action, + u16 token, u32 next_table_index) +{ + int i; + vlib_lex_main_t *lm = &vlib_lex_main; + vlib_lex_table_t *t = pool_elt_at_index (lm->lex_tables, table_index); + + for (i = lo; i <= hi; i++) + { + ASSERT (i < ARRAY_LEN (t->entries)); + t->entries[i].action = action; + t->entries[i].token = token; + t->entries[i].next_table_index = next_table_index; + } +} + +u16 +vlib_lex_add_table (char *name) +{ + vlib_lex_main_t *lm = &vlib_lex_main; + vlib_lex_table_t *t; + uword *p; + + p = hash_get_mem (lm->lex_tables_by_name, name); + + ASSERT (p == 0); + + pool_get_aligned (lm->lex_tables, t, CLIB_CACHE_LINE_BYTES); + + t->name = name; + + hash_set_mem (lm->lex_tables_by_name, name, t - lm->lex_tables); + + vlib_lex_set_action_range (t - lm->lex_tables, 1, 0x7F, VLIB_LEX_IGNORE, ~0, + t - lm->lex_tables); + + vlib_lex_set_action_range (t - lm->lex_tables, 0, 0, VLIB_LEX_RETURN, + VLIB_LEX_eof, t - lm->lex_tables); + + return t - lm->lex_tables; +} + +void +vlib_lex_reset (vlib_lex_main_t * lm, u8 * input_vector) +{ + if (lm->pushback_vector) + _vec_len (lm->pushback_vector) = 0; + lm->pushback_sp = -1; + + lm->input_vector = input_vector; + lm->current_index = 0; +} + +static clib_error_t * +lex_onetime_init (vlib_main_t * vm) +{ + vlib_lex_main_t *lm = &vlib_lex_main; + + lm->lex_tables_by_name = hash_create_string (0, sizeof (uword)); + lm->lex_tokens_by_name = hash_create_string (0, sizeof (uword)); + lm->lex_keywords = hash_create_string (0, sizeof (uword)); + lm->pushback_sp = -1; + +#define _(f) { u16 tmp = vlib_lex_add_token (lm, #f); ASSERT (tmp == VLIB_LEX_##f); } + foreach_vlib_lex_global_token; +#undef _ + + vec_validate (lm->token_buffer, 127); + _vec_len (lm->token_buffer) = 0; + + return 0; +} + +VLIB_INIT_FUNCTION (lex_onetime_init); + +/* + * fd.io coding-style-patch-verification: ON + * + * Local Variables: + * eval: (c-set-style "gnu") + * End: + */ |