X-Git-Url: http://git.efficios.com/?a=blobdiff_plain;f=src%2Fparam-parse%2Fparam-parse.c;fp=src%2Fparam-parse%2Fparam-parse.c;h=e2385ad81ada129606bf1300cf75eb225f8b5c98;hb=5869b17917abc1d8db6b6c1696e00b5f2ec24eda;hp=0000000000000000000000000000000000000000;hpb=9a04e1a93faf83759056240c9eea704cbaef181c;p=babeltrace.git diff --git a/src/param-parse/param-parse.c b/src/param-parse/param-parse.c new file mode 100644 index 00000000..e2385ad8 --- /dev/null +++ b/src/param-parse/param-parse.c @@ -0,0 +1,708 @@ +/* + * Copyright 2016-2019 Philippe Proulx + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to deal + * in the Software without restriction, including without limitation the rights + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell + * copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE + * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + */ + +#include +#include +#include +#include "common/assert.h" +#include +#include +#include +#include +#include "common/common.h" +#include +#include + +/* INI-style parsing FSM states */ +enum ini_parsing_fsm_state { + /* Expect a map key (identifier) */ + INI_EXPECT_MAP_KEY, + + /* Expect an equal character (`=`) */ + INI_EXPECT_EQUAL, + + /* Expect a value */ + INI_EXPECT_VALUE, + + /* Expect a comma character (`,`) */ + INI_EXPECT_COMMA, +}; + +/* INI-style parsing state variables */ +struct ini_parsing_state { + /* Lexical scanner (owned by this) */ + GScanner *scanner; + + /* Output map value object being filled (owned by this) */ + bt_value *params; + + /* Next expected FSM state */ + enum ini_parsing_fsm_state expecting; + + /* Last decoded map key (owned by this) */ + GString *last_map_key; + + /* Complete INI-style string to parse */ + const char *arg; + + /* Error buffer (weak) */ + GString *ini_error; +}; + +/* + * Appends an "expecting token" error to the INI-style parsing state's + * error buffer. + */ +static +void ini_append_error_expecting(struct ini_parsing_state *state, + GScanner *scanner, const char *expecting) +{ + size_t i; + size_t pos; + + g_string_append_printf(state->ini_error, "Expecting %s:\n", expecting); + + /* Only append error if there's one line */ + if (strchr(state->arg, '\n') || strlen(state->arg) == 0) { + return; + } + + g_string_append_printf(state->ini_error, "\n %s\n", state->arg); + pos = g_scanner_cur_position(scanner) + 4; + + if (!g_scanner_eof(scanner)) { + pos--; + } + + for (i = 0; i < pos; ++i) { + g_string_append_printf(state->ini_error, " "); + } + + g_string_append_printf(state->ini_error, "^\n\n"); +} + +static +void ini_append_oom_error(GString *error) +{ + BT_ASSERT(error); + g_string_append(error, "Out of memory\n"); +} + +/* + * Parses the next token as an unsigned integer. + */ +static +bt_value *ini_parse_uint(struct ini_parsing_state *state) +{ + bt_value *value = NULL; + GTokenType token_type = g_scanner_get_next_token(state->scanner); + + if (token_type != G_TOKEN_INT) { + ini_append_error_expecting(state, state->scanner, + "integer value"); + goto end; + } + + value = bt_value_integer_unsigned_create_init( + state->scanner->value.v_int64); + +end: + return value; +} + +/* + * Parses the next token as a number and returns its negation. + */ +static +bt_value *ini_parse_neg_number(struct ini_parsing_state *state) +{ + bt_value *value = NULL; + GTokenType token_type = g_scanner_get_next_token(state->scanner); + + switch (token_type) { + case G_TOKEN_INT: + { + /* Negative integer */ + uint64_t int_val = state->scanner->value.v_int64; + + if (int_val > (((uint64_t) INT64_MAX) + 1)) { + g_string_append_printf(state->ini_error, + "Integer value -%" PRIu64 " is outside the range of a 64-bit signed integer\n", + int_val); + } else { + value = bt_value_integer_signed_create_init( + -((int64_t) int_val)); + } + + break; + } + case G_TOKEN_FLOAT: + /* Negative floating point number */ + value = bt_value_real_create_init( + -state->scanner->value.v_float); + break; + default: + ini_append_error_expecting(state, state->scanner, "value"); + break; + } + + return value; +} + +static bt_value *ini_parse_value(struct ini_parsing_state *state); + +/* + * Parses the current and following tokens as an array. Arrays are + * formatted as an opening `[`, a list of comma-separated values, and a + * closing `]`. For convenience, this function supports an optional + * trailing comma after the last value. + * + * The current token of the parser must be the opening square bracket + * (`[`) of the array. + */ +static +bt_value *ini_parse_array(struct ini_parsing_state *state) +{ + bt_value *array_value; + GTokenType token_type; + + /* The `[` character must have already been ingested */ + BT_ASSERT(g_scanner_cur_token(state->scanner) == G_TOKEN_CHAR); + BT_ASSERT(g_scanner_cur_value(state->scanner).v_char == '['); + + array_value = bt_value_array_create (); + if (!array_value) { + ini_append_oom_error(state->ini_error); + goto error; + } + + token_type = g_scanner_get_next_token(state->scanner); + + /* While the current token is not a `]` */ + while (!(token_type == G_TOKEN_CHAR && + g_scanner_cur_value(state->scanner).v_char == ']')) { + bt_value *item_value; + bt_value_array_append_element_status append_status; + + /* Parse the item... */ + item_value = ini_parse_value(state); + if (!item_value) { + goto error; + } + + /* ... and add it to the result array */ + append_status = bt_value_array_append_element(array_value, + item_value); + BT_VALUE_PUT_REF_AND_RESET(item_value); + if (append_status < 0) { + goto error; + } + + /* + * Ingest the token following the value. It should be + * either a comma or closing square bracket. + */ + token_type = g_scanner_get_next_token(state->scanner); + if (token_type == G_TOKEN_CHAR && + g_scanner_cur_value(state->scanner).v_char == ',') { + /* + * Ingest the token following the comma. If it + * happens to be a closing square bracket, exit + * the loop and we are done (we allow trailing + * commas). Otherwise, we are ready for the next + * ini_parse_value() call. + */ + token_type = g_scanner_get_next_token(state->scanner); + } else if (token_type != G_TOKEN_CHAR || + g_scanner_cur_value(state->scanner).v_char != ']') { + ini_append_error_expecting(state, state->scanner, + "`,` or `]`"); + goto error; + } + } + + goto end; + +error: + BT_VALUE_PUT_REF_AND_RESET(array_value); + +end: + return array_value; +} + +/* + * Parses the current and following tokens as a map. Maps are + * formatted as an opening `{`, a list of comma-separated entries, and a + * closing `}`. And entry is a key (an unquoted string), an equal sign and + * a value. For convenience, this function supports an optional trailing comma + * after the last value. + * + * The current token of the parser must be the opening curly bracket + * (`{`) of the array. + */ +static +bt_value *ini_parse_map(struct ini_parsing_state *state) +{ + bt_value *map_value; + GTokenType token_type; + gchar *key = NULL; + + /* The `{` character must have already been ingested */ + BT_ASSERT(g_scanner_cur_token(state->scanner) == G_TOKEN_CHAR); + BT_ASSERT(g_scanner_cur_value(state->scanner).v_char == '{'); + + map_value = bt_value_map_create (); + if (!map_value) { + ini_append_oom_error(state->ini_error); + goto error; + } + + token_type = g_scanner_get_next_token(state->scanner); + + /* While the current token is not a `}` */ + while (!(token_type == G_TOKEN_CHAR && + g_scanner_cur_value(state->scanner).v_char == '}')) { + bt_value *entry_value; + bt_value_map_insert_entry_status insert_entry_status; + + /* Expect map key. */ + if (token_type != G_TOKEN_IDENTIFIER) { + ini_append_error_expecting(state, state->scanner, + "unquoted map key"); + goto error; + } + + g_free(key); + key = g_strdup(g_scanner_cur_value(state->scanner).v_identifier); + + token_type = g_scanner_get_next_token(state->scanner); + + /* Expect equal sign. */ + if (token_type != G_TOKEN_CHAR || + g_scanner_cur_value(state->scanner).v_char != '=') { + ini_append_error_expecting(state, + state->scanner, "'='"); + goto error; + } + + token_type = g_scanner_get_next_token(state->scanner); + + /* Parse the entry value... */ + entry_value = ini_parse_value(state); + if (!entry_value) { + goto error; + } + + /* ... and add it to the result map */ + insert_entry_status = + bt_value_map_insert_entry(map_value, key, entry_value); + BT_VALUE_PUT_REF_AND_RESET(entry_value); + if (insert_entry_status != BT_VALUE_MAP_INSERT_ENTRY_STATUS_OK) { + goto error; + } + + /* + * Ingest the token following the value. It should be + * either a comma or closing curly bracket. + */ + token_type = g_scanner_get_next_token(state->scanner); + if (token_type == G_TOKEN_CHAR && + g_scanner_cur_value(state->scanner).v_char == ',') { + /* + * Ingest the token following the comma. If it + * happens to be a closing curly bracket, exit + * the loop and we are done (we allow trailing + * commas). Otherwise, we are ready for the next + * ini_parse_value() call. + */ + token_type = g_scanner_get_next_token(state->scanner); + } else if (token_type != G_TOKEN_CHAR || + g_scanner_cur_value(state->scanner).v_char != '}') { + ini_append_error_expecting(state, state->scanner, + "`,` or `}`"); + goto error; + } + } + + goto end; +error: + BT_VALUE_PUT_REF_AND_RESET(map_value); + +end: + g_free(key); + + return map_value; +} + +/* + * Parses the current token (and the following ones if needed) as a + * value, returning it as a `bt_value *`. + */ +static +bt_value *ini_parse_value(struct ini_parsing_state *state) +{ + bt_value *value = NULL; + GTokenType token_type = state->scanner->token; + + switch (token_type) { + case G_TOKEN_CHAR: + if (state->scanner->value.v_char == '-') { + /* Negative number */ + value = ini_parse_neg_number(state); + } else if (state->scanner->value.v_char == '+') { + /* Unsigned integer */ + value = ini_parse_uint(state); + } else if (state->scanner->value.v_char == '[') { + /* Array */ + value = ini_parse_array(state); + } else if (state->scanner->value.v_char == '{') { + /* Map */ + value = ini_parse_map(state); + } else { + ini_append_error_expecting(state, state->scanner, "value"); + goto end; + } + + break; + case G_TOKEN_INT: + { + /* Positive, signed integer */ + uint64_t int_val = state->scanner->value.v_int64; + + if (int_val > INT64_MAX) { + g_string_append_printf(state->ini_error, + "Integer value %" PRIu64 " is outside the range of a 64-bit signed integer\n", + int_val); + goto end; + } else { + value = bt_value_integer_signed_create_init( + (int64_t) int_val); + } + + break; + } + case G_TOKEN_FLOAT: + /* Positive floating point number */ + value = bt_value_real_create_init(state->scanner->value.v_float); + break; + case G_TOKEN_STRING: + /* Quoted string */ + value = bt_value_string_create_init(state->scanner->value.v_string); + break; + case G_TOKEN_IDENTIFIER: + { + /* + * Using symbols would be appropriate here, but said + * symbols are allowed as map key, so it's easier to + * consider everything an identifier. + * + * If one of the known symbols is not recognized here, + * then fall back to creating a string value. + */ + const char *id = state->scanner->value.v_identifier; + + if (strcmp(id, "null") == 0 || strcmp(id, "NULL") == 0 || + strcmp(id, "nul") == 0) { + value = bt_value_null; + bt_value_get_ref(value); + } else if (strcmp(id, "true") == 0 || strcmp(id, "TRUE") == 0 || + strcmp(id, "yes") == 0 || + strcmp(id, "YES") == 0) { + value = bt_value_bool_create_init(true); + } else if (strcmp(id, "false") == 0 || + strcmp(id, "FALSE") == 0 || + strcmp(id, "no") == 0 || + strcmp(id, "NO") == 0) { + value = bt_value_bool_create_init(false); + } else { + value = bt_value_string_create_init(id); + } + break; + } + default: + /* Unset return value variable will trigger the error */ + ini_append_error_expecting(state, state->scanner, "value"); + break; + } + +end: + return value; +} + +/* + * Handles the current state of the INI parser. + * + * Returns 0 to continue, 1 to end, or a negative value on error. + */ +static +int ini_handle_state(struct ini_parsing_state *state) +{ + int ret = 0; + GTokenType token_type; + bt_value *value = NULL; + + token_type = g_scanner_get_next_token(state->scanner); + if (token_type == G_TOKEN_EOF) { + if (state->expecting != INI_EXPECT_COMMA) { + switch (state->expecting) { + case INI_EXPECT_EQUAL: + ini_append_error_expecting(state, + state->scanner, "`=`"); + break; + case INI_EXPECT_VALUE: + ini_append_error_expecting(state, + state->scanner, "value"); + break; + case INI_EXPECT_MAP_KEY: + ini_append_error_expecting(state, + state->scanner, "unquoted map key"); + break; + default: + break; + } + goto error; + } + + /* We're done! */ + ret = 1; + goto success; + } + + switch (state->expecting) { + case INI_EXPECT_MAP_KEY: + if (token_type != G_TOKEN_IDENTIFIER) { + ini_append_error_expecting(state, state->scanner, + "unquoted map key"); + goto error; + } + + g_string_assign(state->last_map_key, + state->scanner->value.v_identifier); + + if (bt_value_map_has_entry(state->params, + state->last_map_key->str)) { + g_string_append_printf(state->ini_error, + "Duplicate parameter key: `%s`\n", + state->last_map_key->str); + goto error; + } + + state->expecting = INI_EXPECT_EQUAL; + goto success; + case INI_EXPECT_EQUAL: + if (token_type != G_TOKEN_CHAR) { + ini_append_error_expecting(state, + state->scanner, "'='"); + goto error; + } + + if (state->scanner->value.v_char != '=') { + ini_append_error_expecting(state, + state->scanner, "'='"); + goto error; + } + + state->expecting = INI_EXPECT_VALUE; + goto success; + case INI_EXPECT_VALUE: + { + value = ini_parse_value(state); + if (!value) { + goto error; + } + + state->expecting = INI_EXPECT_COMMA; + goto success; + } + case INI_EXPECT_COMMA: + if (token_type != G_TOKEN_CHAR) { + ini_append_error_expecting(state, + state->scanner, "','"); + goto error; + } + + if (state->scanner->value.v_char != ',') { + ini_append_error_expecting(state, + state->scanner, "','"); + goto error; + } + + state->expecting = INI_EXPECT_MAP_KEY; + goto success; + default: + abort(); + } + +error: + ret = -1; + goto end; + +success: + if (value) { + if (bt_value_map_insert_entry(state->params, + state->last_map_key->str, value)) { + /* Only override return value on error */ + ret = -1; + } + } + +end: + BT_VALUE_PUT_REF_AND_RESET(value); + return ret; +} + +/* + * Converts an INI-style argument to an equivalent map value object. + * + * Return value is owned by the caller. + */ +BT_HIDDEN +bt_value *bt_param_parse(const char *arg, GString *ini_error) +{ + /* Lexical scanner configuration */ + GScannerConfig scanner_config = { + /* Skip whitespaces */ + .cset_skip_characters = " \t\n", + + /* Identifier syntax is: [a-zA-Z_][a-zA-Z0-9_.:-]* */ + .cset_identifier_first = + G_CSET_a_2_z + "_" + G_CSET_A_2_Z, + .cset_identifier_nth = + G_CSET_a_2_z + "_0123456789-.:" + G_CSET_A_2_Z, + + /* "hello" and "Hello" two different keys */ + .case_sensitive = TRUE, + + /* No comments */ + .cpair_comment_single = NULL, + .skip_comment_multi = TRUE, + .skip_comment_single = TRUE, + .scan_comment_multi = FALSE, + + /* + * Do scan identifiers, including 1-char identifiers, + * but NULL is a normal identifier. + */ + .scan_identifier = TRUE, + .scan_identifier_1char = TRUE, + .scan_identifier_NULL = FALSE, + + /* + * No specific symbols: null and boolean "symbols" are + * scanned as plain identifiers. + */ + .scan_symbols = FALSE, + .symbol_2_token = FALSE, + .scope_0_fallback = FALSE, + + /* + * Scan "0b"-, "0"-, and "0x"-prefixed integers, but not + * integers prefixed with "$". + */ + .scan_binary = TRUE, + .scan_octal = TRUE, + .scan_float = TRUE, + .scan_hex = TRUE, + .scan_hex_dollar = FALSE, + + /* Convert scanned numbers to integer tokens */ + .numbers_2_int = TRUE, + + /* Support both integers and floating point numbers */ + .int_2_float = FALSE, + + /* Scan integers as 64-bit signed integers */ + .store_int64 = TRUE, + + /* Only scan double-quoted strings */ + .scan_string_sq = FALSE, + .scan_string_dq = TRUE, + + /* Do not converter identifiers to string tokens */ + .identifier_2_string = FALSE, + + /* Scan characters as `G_TOKEN_CHAR` token */ + .char_2_token = FALSE, + }; + struct ini_parsing_state state = { + .scanner = NULL, + .params = NULL, + .expecting = INI_EXPECT_MAP_KEY, + .arg = arg, + .ini_error = ini_error, + }; + + BT_ASSERT(ini_error); + g_string_assign(ini_error, ""); + state.params = bt_value_map_create(); + if (!state.params) { + ini_append_oom_error(ini_error); + goto error; + } + + state.scanner = g_scanner_new(&scanner_config); + if (!state.scanner) { + ini_append_oom_error(ini_error); + goto error; + } + + state.last_map_key = g_string_new(NULL); + if (!state.last_map_key) { + ini_append_oom_error(ini_error); + goto error; + } + + /* Let the scan begin */ + g_scanner_input_text(state.scanner, arg, strlen(arg)); + + while (true) { + int ret = ini_handle_state(&state); + + if (ret < 0) { + /* Error */ + goto error; + } else if (ret > 0) { + /* Done */ + break; + } + } + + goto end; + +error: + BT_VALUE_PUT_REF_AND_RESET(state.params); + +end: + if (state.scanner) { + g_scanner_destroy(state.scanner); + } + + if (state.last_map_key) { + g_string_free(state.last_map_key, TRUE); + } + + return state.params; +}