X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/2346344a0890851df35f466909b367cbcaee26a3..3208e3f4d9aff080a546685560536336f0852bcb:/src/scan-gram.l diff --git a/src/scan-gram.l b/src/scan-gram.l index dbe40b9c..5c0418c6 100644 --- a/src/scan-gram.l +++ b/src/scan-gram.l @@ -1,12 +1,13 @@ /* Bison Grammar Scanner -*- C -*- - Copyright (C) 2002, 2003, 2004, 2005, 2006 Free Software Foundation, Inc. + Copyright (C) 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009 + Free Software Foundation, Inc. This file is part of Bison, the GNU Compiler Compiler. - This program is free software; you can redistribute it and/or modify + This program 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 2 of the License, or + the Free Software Foundation, either version 3 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, @@ -15,10 +16,7 @@ GNU General Public License for more details. You should have received a copy of the GNU General Public License - along with this program; if not, write to the Free Software - Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA - 02110-1301 USA -*/ + along with this program. If not, see . */ %option debug nodefault nounput noyywrap never-interactive %option prefix="gram_" outfile="lex.yy.c" @@ -30,20 +28,19 @@ #define gram_wrap() 1 #define FLEX_PREFIX(Id) gram_ ## Id -#include "flex-scanner.h" +#include -#include "complain.h" -#include "files.h" -#include "getargs.h" /* yacc_flag */ -#include "gram.h" -#include "quotearg.h" -#include "reader.h" -#include "uniqstr.h" +#include +#include +#include +#include +#include +#include #include #include -#include "scan-gram.h" +#include #define YY_DECL GRAM_LEX_DECL @@ -51,15 +48,33 @@ code_start = scanner_cursor = loc->start; \ /* Location of scanner cursor. */ -boundary scanner_cursor; +static boundary scanner_cursor; #define YY_USER_ACTION location_compute (loc, &scanner_cursor, yytext, yyleng); static size_t no_cr_read (FILE *, char *, size_t); #define YY_INPUT(buf, result, size) ((result) = no_cr_read (yyin, buf, size)) +#define RETURN_PERCENT_FLAG(Value) \ + do { \ + val->uniqstr = uniqstr_new (Value); \ + return PERCENT_FLAG; \ + } while (0) + +#define ROLLBACK_CURRENT_TOKEN \ + do { \ + scanner_cursor.column -= mbsnwidth (yytext, yyleng, 0); \ + yyless (0); \ + } while (0) + /* A string representing the most recently saved token. */ -char *last_string; +static char *last_string; + +/* Bracketed identifier. */ +static uniqstr bracketed_id_str = 0; +static location bracketed_id_loc; +static boundary bracketed_id_start; +static int bracketed_id_context_state = 0; void gram_scanner_last_string_free (void) @@ -67,10 +82,6 @@ gram_scanner_last_string_free (void) STRING_FREE; } -/* The location of the most recently saved token, if it was a - BRACED_CODE token; otherwise, this has an unspecified value. */ -location gram_last_braced_code_loc; - static void handle_syncline (char *, location); static unsigned long int scan_integer (char const *p, int base, location loc); static int convert_ucn_to_byte (char const *hex_text); @@ -85,9 +96,8 @@ static void unexpected_newline (boundary, char const *); /* A identifier was just read in directives/rules. Special state to capture the sequence `identifier :'. */ %x SC_AFTER_IDENTIFIER - /* A keyword that should be followed by some code was read (e.g. - %printer). */ -%x SC_PRE_CODE + /* A complex tag, with nested angles brackets. */ +%x SC_TAG /* Three types of user code: - prologue (code between `%{' `%}' in the first section, before %%); @@ -98,16 +108,20 @@ static void unexpected_newline (boundary, char const *); %x SC_COMMENT SC_LINE_COMMENT /* Strings and characters in code. */ %x SC_STRING SC_CHARACTER + /* Bracketed identifiers support. */ +%x SC_BRACKETED_ID SC_RETURN_BRACKETED_ID -letter [.abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ_] +letter [-.abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ_] id {letter}({letter}|[0-9])* -directive %{letter}({letter}|[0-9]|-)* +directive %{id} int [0-9]+ /* POSIX says that a tag must be both an id and a C union member, but historically almost any character is allowed in a tag. We disallow - NUL and newline, as this simplifies our implementation. */ -tag [^\0\n>]+ + NUL, as this simplifies our implementation. We disallow angle + bracket to match them in nested pairs: several languages use them + for generics/template types. */ +tag [^\0<>]+ /* Zero or more instances of backslash-newline. Following GCC, allow white space between the backslash and the newline. */ @@ -115,15 +129,13 @@ splice (\\[ \f\t\v]*\n)* %% %{ - /* Nesting level of the current code in braces. */ - int braces_level IF_LINT (= 0); + /* Nesting level. Either for nested braces, or nested angle brackets + (but not mixed). */ + int nesting IF_LINT (= 0); /* Parent context state, when applicable. */ int context_state IF_LINT (= 0); - /* Token type to return, when applicable. */ - int token_type IF_LINT (= 0); - /* Location of most recent identifier, when applicable. */ location id_loc IF_LINT (= empty_location); @@ -142,7 +154,7 @@ splice (\\[ \f\t\v]*\n)* | Scanning white space. | `-----------------------*/ - + { /* Comments and white space. */ "," warn_at (*loc, _("stray `,' treated as white space")); @@ -165,48 +177,58 @@ splice (\\[ \f\t\v]*\n)* /*----------------------------. | Scanning Bison directives. | `----------------------------*/ + + /* For directives that are also command line options, the regex must be + "%..." + after "[-_]"s are removed, and the directive must match the --long + option name, with a single string argument. Otherwise, add exceptions + to ../build-aux/cross-options.pl. */ + { - "%binary" return PERCENT_NONASSOC; - "%debug" return PERCENT_DEBUG; - "%default"[-_]"prec" return PERCENT_DEFAULT_PREC; - "%define" return PERCENT_DEFINE; - "%defines" return PERCENT_DEFINES; - "%destructor" /* FIXME: Remove once %union handled differently. */ token_type = BRACED_CODE; return PERCENT_DESTRUCTOR; - "%dprec" return PERCENT_DPREC; - "%error"[-_]"verbose" return PERCENT_ERROR_VERBOSE; - "%expect" return PERCENT_EXPECT; - "%expect"[-_]"rr" return PERCENT_EXPECT_RR; - "%file-prefix" return PERCENT_FILE_PREFIX; + "%binary" return PERCENT_NONASSOC; + "%code" return PERCENT_CODE; + "%debug" RETURN_PERCENT_FLAG("parse.trace"); + "%default"[-_]"prec" return PERCENT_DEFAULT_PREC; + "%define" return PERCENT_DEFINE; + "%defines" return PERCENT_DEFINES; + "%destructor" return PERCENT_DESTRUCTOR; + "%dprec" return PERCENT_DPREC; + "%error"[-_]"verbose" return PERCENT_ERROR_VERBOSE; + "%expect" return PERCENT_EXPECT; + "%expect"[-_]"rr" return PERCENT_EXPECT_RR; + "%file-prefix" return PERCENT_FILE_PREFIX; "%fixed"[-_]"output"[-_]"files" return PERCENT_YACC; - "%initial-action" /* FIXME: Remove once %union handled differently. */ token_type = BRACED_CODE; return PERCENT_INITIAL_ACTION; - "%glr-parser" return PERCENT_GLR_PARSER; - "%left" return PERCENT_LEFT; - "%lex-param" /* FIXME: Remove once %union handled differently. */ token_type = BRACED_CODE; return PERCENT_LEX_PARAM; - "%locations" return PERCENT_LOCATIONS; - "%merge" return PERCENT_MERGE; - "%name"[-_]"prefix" return PERCENT_NAME_PREFIX; - "%no"[-_]"default"[-_]"prec" return PERCENT_NO_DEFAULT_PREC; - "%no"[-_]"lines" return PERCENT_NO_LINES; - "%nonassoc" return PERCENT_NONASSOC; - "%nondeterministic-parser" return PERCENT_NONDETERMINISTIC_PARSER; - "%nterm" return PERCENT_NTERM; - "%output" return PERCENT_OUTPUT; - "%parse-param" /* FIXME: Remove once %union handled differently. */ token_type = BRACED_CODE; return PERCENT_PARSE_PARAM; - "%prec" return PERCENT_PREC; - "%printer" /* FIXME: Remove once %union handled differently. */ token_type = BRACED_CODE; return PERCENT_PRINTER; - "%pure"[-_]"parser" return PERCENT_PURE_PARSER; - "%require" return PERCENT_REQUIRE; - "%right" return PERCENT_RIGHT; - "%skeleton" return PERCENT_SKELETON; - "%start" return PERCENT_START; - "%term" return PERCENT_TOKEN; - "%token" return PERCENT_TOKEN; - "%token"[-_]"table" return PERCENT_TOKEN_TABLE; - "%type" return PERCENT_TYPE; - "%union" token_type = PERCENT_UNION; BEGIN SC_PRE_CODE; - "%verbose" return PERCENT_VERBOSE; - "%yacc" return PERCENT_YACC; + "%initial-action" return PERCENT_INITIAL_ACTION; + "%glr-parser" return PERCENT_GLR_PARSER; + "%language" return PERCENT_LANGUAGE; + "%left" return PERCENT_LEFT; + "%lex-param" return PERCENT_LEX_PARAM; + "%locations" RETURN_PERCENT_FLAG("locations"); + "%merge" return PERCENT_MERGE; + "%name"[-_]"prefix" return PERCENT_NAME_PREFIX; + "%no"[-_]"default"[-_]"prec" return PERCENT_NO_DEFAULT_PREC; + "%no"[-_]"lines" return PERCENT_NO_LINES; + "%nonassoc" return PERCENT_NONASSOC; + "%nondeterministic-parser" return PERCENT_NONDETERMINISTIC_PARSER; + "%nterm" return PERCENT_NTERM; + "%output" return PERCENT_OUTPUT; + "%parse-param" return PERCENT_PARSE_PARAM; + "%prec" return PERCENT_PREC; + "%precedence" return PERCENT_PRECEDENCE; + "%printer" return PERCENT_PRINTER; + "%pure"[-_]"parser" RETURN_PERCENT_FLAG("api.pure"); + "%require" return PERCENT_REQUIRE; + "%right" return PERCENT_RIGHT; + "%skeleton" return PERCENT_SKELETON; + "%start" return PERCENT_START; + "%term" return PERCENT_TOKEN; + "%token" return PERCENT_TOKEN; + "%token"[-_]"table" return PERCENT_TOKEN_TABLE; + "%type" return PERCENT_TYPE; + "%union" return PERCENT_UNION; + "%verbose" return PERCENT_VERBOSE; + "%yacc" return PERCENT_YACC; {directive} { complain_at (*loc, _("invalid directive: %s"), quote (yytext)); @@ -217,8 +239,9 @@ splice (\\[ \f\t\v]*\n)* ";" return SEMICOLON; {id} { - val->symbol = symbol_get (yytext, *loc); + val->uniqstr = uniqstr_new (yytext); id_loc = *loc; + bracketed_id_str = NULL; BEGIN SC_AFTER_IDENTIFIER; } @@ -231,7 +254,13 @@ splice (\\[ \f\t\v]*\n)* return INT; } - /* Characters. We don't check there is only one. */ + /* Identifiers may not start with a digit. Yet, don't silently + accept "1FOO" as "1 FOO". */ + {int}{id} { + complain_at (*loc, _("invalid identifier: %s"), quote (yytext)); + } + + /* Characters. */ "'" STRING_GROW; token_start = loc->start; BEGIN SC_ESCAPED_CHARACTER; /* Strings. */ @@ -242,22 +271,26 @@ splice (\\[ \f\t\v]*\n)* /* Code in between braces. */ "{" { - if (current_rule && current_rule->action) - grammar_midrule_action (); STRING_GROW; - token_type = BRACED_CODE; - braces_level = 0; + nesting = 0; code_start = loc->start; BEGIN SC_BRACED_CODE; } /* A type. */ + "<*>" return TAG_ANY; + "<>" return TAG_NONE; "<"{tag}">" { obstack_grow (&obstack_for_string, yytext + 1, yyleng - 2); STRING_FINISH; val->uniqstr = uniqstr_new (last_string); STRING_FREE; - return TYPE; + return TAG; + } + "<" { + nesting = 0; + token_start = loc->start; + BEGIN SC_TAG; } "%%" { @@ -267,6 +300,13 @@ splice (\\[ \f\t\v]*\n)* return PERCENT_PERCENT; } + "[" { + bracketed_id_str = NULL; + bracketed_id_start = loc->start; + bracketed_id_context_state = YY_START; + BEGIN SC_BRACKETED_ID; + } + . { complain_at (*loc, _("invalid character: %s"), quote (yytext)); } @@ -278,31 +318,111 @@ splice (\\[ \f\t\v]*\n)* } + /*--------------------------------------------------------------. + | Supporting \0 complexifies our implementation for no expected | + | added value. | + `--------------------------------------------------------------*/ + + +{ + \0 complain_at (*loc, _("invalid null character")); +} + + /*-----------------------------------------------------------------. | Scanning after an identifier, checking whether a colon is next. | `-----------------------------------------------------------------*/ { + "[" { + if (bracketed_id_str) + { + ROLLBACK_CURRENT_TOKEN; + BEGIN SC_RETURN_BRACKETED_ID; + *loc = id_loc; + return ID; + } + else + { + bracketed_id_start = loc->start; + bracketed_id_context_state = YY_START; + BEGIN SC_BRACKETED_ID; + } + } ":" { + BEGIN (bracketed_id_str ? SC_RETURN_BRACKETED_ID : INITIAL); *loc = id_loc; - BEGIN INITIAL; return ID_COLON; } . { - scanner_cursor.column -= mbsnwidth (yytext, yyleng, 0); - yyless (0); + ROLLBACK_CURRENT_TOKEN; + BEGIN (bracketed_id_str ? SC_RETURN_BRACKETED_ID : INITIAL); *loc = id_loc; - BEGIN INITIAL; return ID; } <> { + BEGIN (bracketed_id_str ? SC_RETURN_BRACKETED_ID : INITIAL); *loc = id_loc; - BEGIN INITIAL; return ID; } } + /*--------------------------------. + | Scanning bracketed identifiers. | + `--------------------------------*/ + + +{ + {id} { + if (bracketed_id_str) + { + complain_at (*loc, _("unexpected identifier in bracketed name: %s"), + quote (yytext)); + } + else + { + bracketed_id_str = uniqstr_new (yytext); + bracketed_id_loc = *loc; + } + } + "]" { + BEGIN bracketed_id_context_state; + if (bracketed_id_str) + { + if (INITIAL == bracketed_id_context_state) + { + val->uniqstr = bracketed_id_str; + bracketed_id_str = 0; + *loc = bracketed_id_loc; + return BRACKETED_ID; + } + } + else + complain_at (*loc, _("an identifier expected")); + } + . { + complain_at (*loc, _("invalid character in bracketed name: %s"), + quote (yytext)); + } + <> { + BEGIN bracketed_id_context_state; + unexpected_eof (bracketed_id_start, "]"); + } +} + + +{ + . { + ROLLBACK_CURRENT_TOKEN; + val->uniqstr = bracketed_id_str; + bracketed_id_str = 0; + *loc = bracketed_id_loc; + BEGIN INITIAL; + return BRACKETED_ID; + } +} + /*---------------------------------------------------------------. | Scanning a Yacc comment. The initial `/ *' is already eaten. | @@ -346,15 +466,23 @@ splice (\\[ \f\t\v]*\n)* { - "\"" { + "\""|"\n" { + if (yytext[0] == '\n') + unexpected_newline (token_start, "\""); + STRING_FINISH; + loc->start = token_start; + val->chars = last_string; + BEGIN INITIAL; + return STRING; + } + <> { + unexpected_eof (token_start, "\""); STRING_FINISH; loc->start = token_start; val->chars = last_string; BEGIN INITIAL; return STRING; } - \n unexpected_newline (token_start, "\""); BEGIN INITIAL; - <> unexpected_eof (token_start, "\""); BEGIN INITIAL; } /*----------------------------------------------------------. @@ -364,30 +492,81 @@ splice (\\[ \f\t\v]*\n)* { - "'" { - unsigned char last_string_1; + "'"|"\n" { STRING_GROW; STRING_FINISH; loc->start = token_start; - val->symbol = symbol_get (quotearg_style (escape_quoting_style, - last_string), - *loc); - symbol_class_set (val->symbol, token_sym, *loc, false); - last_string_1 = last_string[1]; - symbol_user_token_number_set (val->symbol, last_string_1, *loc); + val->character = last_string[1]; + { + /* FIXME: Eventually, make these errors. */ + size_t length = strlen (last_string); + if (strlen (last_string) < 3) + warn_at (*loc, _("empty character literal")); + else if (strlen (last_string) > 3) + warn_at (*loc, _("extra characters in character literal")); + } + if (yytext[0] == '\n') + unexpected_newline (token_start, "'"); STRING_FREE; BEGIN INITIAL; - return ID; + return CHAR; + } + <> { + STRING_FINISH; + loc->start = token_start; + { + size_t length = strlen (last_string); + /* FIXME: Eventually, make these errors. */ + if (length < 2) + warn_at (*loc, _("empty character literal")); + else if (length > 2) + warn_at (*loc, _("extra characters in character literal")); + if (length > 1) + val->character = last_string[1]; + else + val->character = last_string[0]; + } + unexpected_eof (token_start, "'"); + STRING_FREE; + BEGIN INITIAL; + return CHAR; } - \n unexpected_newline (token_start, "'"); BEGIN INITIAL; - <> unexpected_eof (token_start, "'"); BEGIN INITIAL; } - + /*-----------------------------------------------------------. + | Scanning a Bison nested tag. The initial angle bracket is | + | already eaten. | + `-----------------------------------------------------------*/ + + { - \0 complain_at (*loc, _("invalid null character")); -} + ">" { + --nesting; + if (nesting < 0) + { + STRING_FINISH; + loc->start = token_start; + val->uniqstr = uniqstr_new (last_string); + STRING_FREE; + BEGIN INITIAL; + return TAG; + } + STRING_GROW; + } + [^<>]+ STRING_GROW; + "<"+ STRING_GROW; nesting += yyleng; + + <> { + unexpected_eof (token_start, ">"); + STRING_FINISH; + loc->start = token_start; + val->uniqstr = uniqstr_new (last_string); + STRING_FREE; + BEGIN INITIAL; + return TAG; + } +} /*----------------------------. | Decode escaped characters. | @@ -498,62 +677,27 @@ splice (\\[ \f\t\v]*\n)* } - /*---------------------------------------------------------------. - | Scanning after %union etc., possibly followed by white space. | - | For %union only, allow arbitrary C code to appear before the | - | following brace, as an extension to POSIX. | - `---------------------------------------------------------------*/ - - -{ - . { - bool valid = yytext[0] == '{' || token_type == PERCENT_UNION; - scanner_cursor.column -= mbsnwidth (yytext, yyleng, 0); - yyless (0); - - if (valid) - { - braces_level = -1; - code_start = loc->start; - BEGIN SC_BRACED_CODE; - } - else - { - complain_at (*loc, _("missing `{' in %s"), - token_name (token_type)); - obstack_sgrow (&obstack_for_string, "{}"); - STRING_FINISH; - val->chars = last_string; - BEGIN INITIAL; - return token_type; - } - } - - <> unexpected_eof (scanner_cursor, "{}"); BEGIN INITIAL; -} - - /*---------------------------------------------------------------. - | Scanning some code in braces (%union and actions). The initial | - | "{" is already eaten. | - `---------------------------------------------------------------*/ + /*-----------------------------------------------------------. + | Scanning some code in braces (actions). The initial "{" is | + | already eaten. | + `-----------------------------------------------------------*/ { - "{"|"<"{splice}"%" STRING_GROW; braces_level++; - "%"{splice}">" STRING_GROW; braces_level--; + "{"|"<"{splice}"%" STRING_GROW; nesting++; + "%"{splice}">" STRING_GROW; nesting--; "}" { obstack_1grow (&obstack_for_string, '}'); - --braces_level; - if (braces_level < 0) + --nesting; + if (nesting < 0) { STRING_FINISH; loc->start = code_start; - val->chars = last_string; - gram_last_braced_code_loc = *loc; + val->code = last_string; BEGIN INITIAL; - return token_type; + return BRACED_CODE; } } @@ -561,7 +705,14 @@ splice (\\[ \f\t\v]*\n)* (as `<' `<%'). */ "<"{splice}"<" STRING_GROW; - <> unexpected_eof (code_start, "}"); BEGIN INITIAL; + <> { + unexpected_eof (code_start, "}"); + STRING_FINISH; + loc->start = code_start; + val->code = last_string; + BEGIN INITIAL; + return BRACED_CODE; + } } @@ -579,7 +730,14 @@ splice (\\[ \f\t\v]*\n)* return PROLOGUE; } - <> unexpected_eof (code_start, "%}"); BEGIN INITIAL; + <> { + unexpected_eof (code_start, "%}"); + STRING_FINISH; + loc->start = code_start; + val->chars = last_string; + BEGIN INITIAL; + return PROLOGUE; + } } @@ -751,7 +909,7 @@ handle_syncline (char *args, location loc) lineno = INT_MAX; } current_file = uniqstr_new (file); - boundary_set, (&scanner_cursor, current_file, lineno, 1); + boundary_set (&scanner_cursor, current_file, lineno, 1); } @@ -814,5 +972,5 @@ gram_scanner_free (void) { obstack_free (&obstack_for_string, 0); /* Reclaim Flex's buffers. */ - yy_delete_buffer (YY_CURRENT_BUFFER); + yylex_destroy (); }