diff options
author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 16:29:51 +0000 |
---|---|---|
committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 16:29:51 +0000 |
commit | 6e7a315eb67cb6c113cf37e1d66c4f11a51a2b3e (patch) | |
tree | 32451fa3cdd9321fb2591fada9891b2cb70a9cd1 /grub-core/script/lexer.c | |
parent | Initial commit. (diff) | |
download | grub2-upstream.tar.xz grub2-upstream.zip |
Adding upstream version 2.06.upstream/2.06upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'grub-core/script/lexer.c')
-rw-r--r-- | grub-core/script/lexer.c | 356 |
1 files changed, 356 insertions, 0 deletions
diff --git a/grub-core/script/lexer.c b/grub-core/script/lexer.c new file mode 100644 index 0000000..52004d0 --- /dev/null +++ b/grub-core/script/lexer.c @@ -0,0 +1,356 @@ +/* lexer.c - The scripting lexer. */ +/* + * GRUB -- GRand Unified Bootloader + * Copyright (C) 2005,2006,2007,2008,2009,2010 Free Software Foundation, Inc. + * + * GRUB is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation, either version 3 of the License, or + * (at your option) any later version. + * + * GRUB is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with GRUB. If not, see <http://www.gnu.org/licenses/>. + */ + +#include <config.h> + +#include <grub/parser.h> +#include <grub/misc.h> +#include <grub/mm.h> +#include <grub/script_sh.h> +#include <grub/i18n.h> +#include <grub/safemath.h> + +#define yytext_ptr char * +#include "grub_script.tab.h" +#include "grub_script.yy.h" + +void +grub_script_lexer_ref (struct grub_lexer_param *state) +{ + state->refs++; +} + +void +grub_script_lexer_deref (struct grub_lexer_param *state) +{ + state->refs--; +} + +/* Start recording all characters passing through the lexer. */ +unsigned +grub_script_lexer_record_start (struct grub_parser_param *parser) +{ + struct grub_lexer_param *lexer = parser->lexerstate; + + lexer->record++; + if (lexer->recording) + return lexer->recordpos; + + lexer->recordpos = 0; + lexer->recordlen = GRUB_LEXER_INITIAL_RECORD_SIZE; + lexer->recording = grub_malloc (lexer->recordlen); + if (!lexer->recording) + { + grub_script_yyerror (parser, 0); + lexer->recordlen = 0; + } + return lexer->recordpos; +} + +char * +grub_script_lexer_record_stop (struct grub_parser_param *parser, unsigned offset) +{ + int count; + char *result; + struct grub_lexer_param *lexer = parser->lexerstate; + + if (!lexer->record) + return 0; + + lexer->record--; + if (!lexer->recording) + return 0; + + count = lexer->recordpos - offset; + result = grub_script_malloc (parser, count + 1); + if (result) { + grub_strncpy (result, lexer->recording + offset, count); + result[count] = '\0'; + } + + if (lexer->record == 0) + { + grub_free (lexer->recording); + lexer->recording = 0; + lexer->recordlen = 0; + lexer->recordpos = 0; + } + return result; +} + +/* Record STR if input recording is enabled. */ +void +grub_script_lexer_record (struct grub_parser_param *parser, char *str) +{ + int len; + char *old; + struct grub_lexer_param *lexer = parser->lexerstate; + + if (!lexer->record || !lexer->recording) + return; + + len = grub_strlen (str); + if (lexer->recordpos + len + 1 > lexer->recordlen) + { + old = lexer->recording; + if (lexer->recordlen < len) + lexer->recordlen = len; + + if (grub_mul (lexer->recordlen, 2, &lexer->recordlen)) + goto fail; + + lexer->recording = grub_realloc (lexer->recording, lexer->recordlen); + if (!lexer->recording) + { + fail: + grub_free (old); + lexer->recordpos = 0; + lexer->recordlen = 0; + grub_script_yyerror (parser, 0); + return; + } + } + grub_strcpy (lexer->recording + lexer->recordpos, str); + lexer->recordpos += len; +} + +/* Read next line of input if necessary, and set yyscanner buffers. */ +int +grub_script_lexer_yywrap (struct grub_parser_param *parserstate, + const char *input) +{ + grub_size_t len = 0, sz; + char *p = 0; + char *line = 0; + YY_BUFFER_STATE buffer; + struct grub_lexer_param *lexerstate = parserstate->lexerstate; + + if (! lexerstate->refs && ! lexerstate->prefix && ! input) + return 1; + + if (! lexerstate->getline && ! input) + { + grub_script_yyerror (parserstate, N_("unexpected end of file")); + return 1; + } + + line = 0; + if (! input) + lexerstate->getline (&line, 1, lexerstate->getline_data); + else + line = grub_strdup (input); + + if (! line) + { + grub_script_yyerror (parserstate, N_("out of memory")); + return 1; + } + + len = grub_strlen (line); + + /* Ensure '\n' at the end. */ + if (line[0] == '\0') + { + grub_free (line); + line = grub_strdup ("\n"); + len = 1; + } + else if (len && line[len - 1] != '\n') + { + if (grub_add (len, 2, &sz)) + { + grub_free (line); + grub_script_yyerror (parserstate, N_("overflow is detected")); + return 1; + } + + p = grub_realloc (line, sz); + if (p) + { + p[len++] = '\n'; + p[len] = '\0'; + } + else + grub_free (line); + + line = p; + } + + if (! line) + { + grub_script_yyerror (parserstate, N_("out of memory")); + return 1; + } + + /* Prepend any left over unput-text. */ + if (lexerstate->prefix) + { + int plen = grub_strlen (lexerstate->prefix); + + p = grub_malloc (len + plen + 1); + if (! p) + { + grub_free (line); + return 1; + } + grub_strcpy (p, lexerstate->prefix); + lexerstate->prefix = 0; + + grub_strcpy (p + plen, line); + grub_free (line); + + line = p; + len = len + plen; + } + + buffer = yy_scan_string (line, lexerstate->yyscanner); + grub_free (line); + + if (! buffer) + { + grub_script_yyerror (parserstate, 0); + return 1; + } + return 0; +} + +struct grub_lexer_param * +grub_script_lexer_init (struct grub_parser_param *parser, char *script, + grub_reader_getline_t arg_getline, void *getline_data) +{ + struct grub_lexer_param *lexerstate; + + lexerstate = grub_zalloc (sizeof (*lexerstate)); + if (!lexerstate) + return 0; + + lexerstate->size = GRUB_LEXER_INITIAL_TEXT_SIZE; + lexerstate->text = grub_malloc (lexerstate->size); + if (!lexerstate->text) + { + grub_free (lexerstate); + return 0; + } + + lexerstate->getline = arg_getline; + lexerstate->getline_data = getline_data; + /* The other elements of lexerstate are all zeros already. */ + + if (yylex_init (&lexerstate->yyscanner)) + { + grub_free (lexerstate->text); + grub_free (lexerstate); + return 0; + } + + yyset_extra (parser, lexerstate->yyscanner); + parser->lexerstate = lexerstate; + + if (grub_script_lexer_yywrap (parser, script ?: "\n")) + { + parser->lexerstate = 0; + yylex_destroy (lexerstate->yyscanner); + grub_free (lexerstate->text); + grub_free (lexerstate); + return 0; + } + + return lexerstate; +} + +void +grub_script_lexer_fini (struct grub_lexer_param *lexerstate) +{ + if (!lexerstate) + return; + + yylex_destroy (lexerstate->yyscanner); + + grub_free (lexerstate->recording); + grub_free (lexerstate->text); + grub_free (lexerstate); +} + +int +grub_script_yylex (union YYSTYPE *value, + struct grub_parser_param *parserstate) +{ + char *str; + int token; + grub_script_arg_type_t type; + struct grub_lexer_param *lexerstate = parserstate->lexerstate; + + value->arg = 0; + if (parserstate->err) + return GRUB_PARSER_TOKEN_BAD; + + if (lexerstate->eof) + return GRUB_PARSER_TOKEN_EOF; + + /* + * Words with environment variables, like foo${bar}baz needs + * multiple tokens to be merged into a single grub_script_arg. We + * use two variables to achieve this: lexerstate->merge_start and + * lexerstate->merge_end + */ + + lexerstate->merge_start = 0; + lexerstate->merge_end = 0; + do + { + /* Empty lexerstate->text. */ + lexerstate->used = 1; + lexerstate->text[0] = '\0'; + + token = yylex (value, lexerstate->yyscanner); + if (token == GRUB_PARSER_TOKEN_BAD) + break; + + /* Merging feature uses lexerstate->text instead of yytext. */ + if (lexerstate->merge_start) + { + str = lexerstate->text; + type = lexerstate->type; + } + else + { + str = yyget_text (lexerstate->yyscanner); + type = GRUB_SCRIPT_ARG_TYPE_TEXT; + } + grub_dprintf("lexer", "token %u text [%s]\n", token, str); + + value->arg = grub_script_arg_add (parserstate, value->arg, type, str); + } + while (lexerstate->merge_start && !lexerstate->merge_end); + + if (!value->arg || parserstate->err) + return GRUB_PARSER_TOKEN_BAD; + + return token; +} + +void +grub_script_yyerror (struct grub_parser_param *state, const char *err) +{ + if (err) + grub_error (GRUB_ERR_INVALID_COMMAND, "%s", err); + + grub_print_error (); + state->err++; +} |