/* Bison Grammar Scanner -*- C -*- Copyright (C) 2002, 2003, 2004, 2005, 2006, 2007, 2008 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 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. This program 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 this program. If not, see . */ %option debug nodefault nounput noyywrap never-interactive %option prefix="gram_" outfile="lex.yy.c" %{ /* Work around a bug in flex 2.5.31. See Debian bug 333231 . */ #undef gram_wrap #define gram_wrap() 1 #define FLEX_PREFIX(Id) gram_ ## Id #include "flex-scanner.h" #include "complain.h" #include "files.h" #include "gram.h" #include "quotearg.h" #include "reader.h" #include "uniqstr.h" #include #include #include "scan-gram.h" #define YY_DECL GRAM_LEX_DECL #define YY_USER_INIT \ code_start = scanner_cursor = loc->start; \ /* Location of 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)) /* A string representing the most recently saved token. */ static char *last_string; void gram_scanner_last_string_free (void) { STRING_FREE; } 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); static void unexpected_eof (boundary, char const *); static void unexpected_newline (boundary, char const *); %} /* A C-like comment in directives/rules. */ %x SC_YACC_COMMENT /* Strings and characters in directives/rules. */ %x SC_ESCAPED_STRING SC_ESCAPED_CHARACTER /* A identifier was just read in directives/rules. Special state to capture the sequence `identifier :'. */ %x SC_AFTER_IDENTIFIER /* Three types of user code: - prologue (code between `%{' `%}' in the first section, before %%); - actions, printers, union, etc, (between braced in the middle section); - epilogue (everything after the second %%). */ %x SC_PROLOGUE SC_BRACED_CODE SC_EPILOGUE /* C and C++ comments in code. */ %x SC_COMMENT SC_LINE_COMMENT /* Strings and characters in code. */ %x SC_STRING SC_CHARACTER letter [.abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ_] id {letter}({letter}|[0-9])* directive %{letter}({letter}|[0-9]|-)* 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>]+ /* Zero or more instances of backslash-newline. Following GCC, allow white space between the backslash and the newline. */ splice (\\[ \f\t\v]*\n)* %% %{ /* Nesting level of the current code in braces. */ int braces_level IF_LINT (= 0); /* Parent context state, when applicable. */ int context_state IF_LINT (= 0); /* Location of most recent identifier, when applicable. */ location id_loc IF_LINT (= empty_location); /* Where containing code started, when applicable. Its initial value is relevant only when yylex is invoked in the SC_EPILOGUE start condition. */ boundary code_start = scanner_cursor; /* Where containing comment or string or character literal started, when applicable. */ boundary token_start IF_LINT (= scanner_cursor); %} /*-----------------------. | Scanning white space. | `-----------------------*/ { /* Comments and white space. */ "," warn_at (*loc, _("stray `,' treated as white space")); [ \f\n\t\v] | "//".* ; "/*" { token_start = loc->start; context_state = YY_START; BEGIN SC_YACC_COMMENT; } /* #line directives are not documented, and may be withdrawn or modified in future versions of Bison. */ ^"#line "{int}" \"".*"\"\n" { handle_syncline (yytext + sizeof "#line " - 1, *loc); } } /*----------------------------. | Scanning Bison directives. | `----------------------------*/ { "%binary" return PERCENT_NONASSOC; "%code" return PERCENT_CODE; "%debug" return PERCENT_DEBUG; "%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" 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_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_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" return PERCENT_UNION; "%verbose" return PERCENT_VERBOSE; "%yacc" return PERCENT_YACC; {directive} { complain_at (*loc, _("invalid directive: %s"), quote (yytext)); } "=" return EQUAL; "|" return PIPE; ";" return SEMICOLON; "<*>" return TYPE_TAG_ANY; "<>" return TYPE_TAG_NONE; {id} { val->uniqstr = uniqstr_new (yytext); id_loc = *loc; BEGIN SC_AFTER_IDENTIFIER; } {int} { val->integer = scan_integer (yytext, 10, *loc); return INT; } 0[xX][0-9abcdefABCDEF]+ { val->integer = scan_integer (yytext, 16, *loc); return INT; } /* Characters. We don't check there is only one. */ "'" STRING_GROW; token_start = loc->start; BEGIN SC_ESCAPED_CHARACTER; /* Strings. */ "\"" token_start = loc->start; BEGIN SC_ESCAPED_STRING; /* Prologue. */ "%{" code_start = loc->start; BEGIN SC_PROLOGUE; /* Code in between braces. */ "{" { STRING_GROW; braces_level = 0; code_start = loc->start; BEGIN SC_BRACED_CODE; } /* A type. */ "<"{tag}">" { obstack_grow (&obstack_for_string, yytext + 1, yyleng - 2); STRING_FINISH; val->uniqstr = uniqstr_new (last_string); STRING_FREE; return TYPE; } "%%" { static int percent_percent_count; if (++percent_percent_count == 2) BEGIN SC_EPILOGUE; return PERCENT_PERCENT; } . { complain_at (*loc, _("invalid character: %s"), quote (yytext)); } <> { loc->start = loc->end = scanner_cursor; yyterminate (); } } /*-----------------------------------------------------------------. | Scanning after an identifier, checking whether a colon is next. | `-----------------------------------------------------------------*/ { ":" { *loc = id_loc; BEGIN INITIAL; return ID_COLON; } . { scanner_cursor.column -= mbsnwidth (yytext, yyleng, 0); yyless (0); *loc = id_loc; BEGIN INITIAL; return ID; } <> { *loc = id_loc; BEGIN INITIAL; return ID; } } /*---------------------------------------------------------------. | Scanning a Yacc comment. The initial `/ *' is already eaten. | `---------------------------------------------------------------*/ { "*/" BEGIN context_state; .|\n ; <> unexpected_eof (token_start, "*/"); BEGIN context_state; } /*------------------------------------------------------------. | Scanning a C comment. The initial `/ *' is already eaten. | `------------------------------------------------------------*/ { "*"{splice}"/" STRING_GROW; BEGIN context_state; <> unexpected_eof (token_start, "*/"); BEGIN context_state; } /*--------------------------------------------------------------. | Scanning a line comment. The initial `//' is already eaten. | `--------------------------------------------------------------*/ { "\n" STRING_GROW; BEGIN context_state; {splice} STRING_GROW; <> BEGIN context_state; } /*------------------------------------------------. | Scanning a Bison string, including its escapes. | | The initial quote is already eaten. | `------------------------------------------------*/ { "\""|"\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; } } /*----------------------------------------------------------. | Scanning a Bison character literal, decoding its escapes. | | The initial quote is already eaten. | `----------------------------------------------------------*/ { "'"|"\n" { if (yytext[0] == '\n') unexpected_newline (token_start, "'"); STRING_GROW; STRING_FINISH; loc->start = token_start; val->character = last_string[1]; STRING_FREE; BEGIN INITIAL; return CHAR; } <> { unexpected_eof (token_start, "'"); STRING_FINISH; loc->start = token_start; if (strlen(last_string) > 1) val->character = last_string[1]; else val->character = last_string[0]; STRING_FREE; BEGIN INITIAL; return CHAR; } } { \0 complain_at (*loc, _("invalid null character")); } /*----------------------------. | Decode escaped characters. | `----------------------------*/ { \\[0-7]{1,3} { unsigned long int c = strtoul (yytext + 1, NULL, 8); if (UCHAR_MAX < c) complain_at (*loc, _("invalid escape sequence: %s"), quote (yytext)); else if (! c) complain_at (*loc, _("invalid null character: %s"), quote (yytext)); else obstack_1grow (&obstack_for_string, c); } \\x[0-9abcdefABCDEF]+ { verify (UCHAR_MAX < ULONG_MAX); unsigned long int c = strtoul (yytext + 2, NULL, 16); if (UCHAR_MAX < c) complain_at (*loc, _("invalid escape sequence: %s"), quote (yytext)); else if (! c) complain_at (*loc, _("invalid null character: %s"), quote (yytext)); else obstack_1grow (&obstack_for_string, c); } \\a obstack_1grow (&obstack_for_string, '\a'); \\b obstack_1grow (&obstack_for_string, '\b'); \\f obstack_1grow (&obstack_for_string, '\f'); \\n obstack_1grow (&obstack_for_string, '\n'); \\r obstack_1grow (&obstack_for_string, '\r'); \\t obstack_1grow (&obstack_for_string, '\t'); \\v obstack_1grow (&obstack_for_string, '\v'); /* \\[\"\'?\\] would be shorter, but it confuses xgettext. */ \\("\""|"'"|"?"|"\\") obstack_1grow (&obstack_for_string, yytext[1]); \\(u|U[0-9abcdefABCDEF]{4})[0-9abcdefABCDEF]{4} { int c = convert_ucn_to_byte (yytext); if (c < 0) complain_at (*loc, _("invalid escape sequence: %s"), quote (yytext)); else if (! c) complain_at (*loc, _("invalid null character: %s"), quote (yytext)); else obstack_1grow (&obstack_for_string, c); } \\(.|\n) { complain_at (*loc, _("unrecognized escape sequence: %s"), quote (yytext)); STRING_GROW; } } /*--------------------------------------------. | Scanning user-code characters and strings. | `--------------------------------------------*/ { {splice}|\\{splice}[^\n\[\]] STRING_GROW; } { "'" STRING_GROW; BEGIN context_state; \n unexpected_newline (token_start, "'"); BEGIN context_state; <> unexpected_eof (token_start, "'"); BEGIN context_state; } { "\"" STRING_GROW; BEGIN context_state; \n unexpected_newline (token_start, "\""); BEGIN context_state; <> unexpected_eof (token_start, "\""); BEGIN context_state; } /*---------------------------------------------------. | Strings, comments etc. can be found in user code. | `---------------------------------------------------*/ { "'" { STRING_GROW; context_state = YY_START; token_start = loc->start; BEGIN SC_CHARACTER; } "\"" { STRING_GROW; context_state = YY_START; token_start = loc->start; BEGIN SC_STRING; } "/"{splice}"*" { STRING_GROW; context_state = YY_START; token_start = loc->start; BEGIN SC_COMMENT; } "/"{splice}"/" { STRING_GROW; context_state = YY_START; BEGIN SC_LINE_COMMENT; } } /*-----------------------------------------------------------. | Scanning some code in braces (actions). The initial "{" is | | already eaten. | `-----------------------------------------------------------*/ { "{"|"<"{splice}"%" STRING_GROW; braces_level++; "%"{splice}">" STRING_GROW; braces_level--; "}" { obstack_1grow (&obstack_for_string, '}'); --braces_level; if (braces_level < 0) { STRING_FINISH; loc->start = code_start; val->code = last_string; BEGIN INITIAL; return BRACED_CODE; } } /* Tokenize `<<%' correctly (as `<<' `%') rather than incorrrectly (as `<' `<%'). */ "<"{splice}"<" STRING_GROW; <> { unexpected_eof (code_start, "}"); STRING_FINISH; loc->start = code_start; val->code = last_string; BEGIN INITIAL; return BRACED_CODE; } } /*--------------------------------------------------------------. | Scanning some prologue: from "%{" (already scanned) to "%}". | `--------------------------------------------------------------*/ { "%}" { STRING_FINISH; loc->start = code_start; val->chars = last_string; BEGIN INITIAL; return PROLOGUE; } <> { unexpected_eof (code_start, "%}"); STRING_FINISH; loc->start = code_start; val->chars = last_string; BEGIN INITIAL; return PROLOGUE; } } /*---------------------------------------------------------------. | Scanning the epilogue (everything after the second "%%", which | | has already been eaten). | `---------------------------------------------------------------*/ { <> { STRING_FINISH; loc->start = code_start; val->chars = last_string; BEGIN INITIAL; return EPILOGUE; } } /*-----------------------------------------------------. | By default, grow the string obstack with the input. | `-----------------------------------------------------*/ . | \n STRING_GROW; %% /* Read bytes from FP into buffer BUF of size SIZE. Return the number of bytes read. Remove '\r' from input, treating \r\n and isolated \r as \n. */ static size_t no_cr_read (FILE *fp, char *buf, size_t size) { size_t bytes_read = fread (buf, 1, size, fp); if (bytes_read) { char *w = memchr (buf, '\r', bytes_read); if (w) { char const *r = ++w; char const *lim = buf + bytes_read; for (;;) { /* Found an '\r'. Treat it like '\n', but ignore any '\n' that immediately follows. */ w[-1] = '\n'; if (r == lim) { int ch = getc (fp); if (ch != '\n' && ungetc (ch, fp) != ch) break; } else if (*r == '\n') r++; /* Copy until the next '\r'. */ do { if (r == lim) return w - buf; } while ((*w++ = *r++) != '\r'); } return w - buf; } } return bytes_read; } /*------------------------------------------------------. | Scan NUMBER for a base-BASE integer at location LOC. | `------------------------------------------------------*/ static unsigned long int scan_integer (char const *number, int base, location loc) { verify (INT_MAX < ULONG_MAX); unsigned long int num = strtoul (number, NULL, base); if (INT_MAX < num) { complain_at (loc, _("integer out of range: %s"), quote (number)); num = INT_MAX; } return num; } /*------------------------------------------------------------------. | Convert universal character name UCN to a single-byte character, | | and return that character. Return -1 if UCN does not correspond | | to a single-byte character. | `------------------------------------------------------------------*/ static int convert_ucn_to_byte (char const *ucn) { verify (UCHAR_MAX <= INT_MAX); unsigned long int code = strtoul (ucn + 2, NULL, 16); /* FIXME: Currently we assume Unicode-compatible unibyte characters on ASCII hosts (i.e., Latin-1 on hosts with 8-bit bytes). On non-ASCII hosts we support only the portable C character set. These limitations should be removed once we add support for multibyte characters. */ if (UCHAR_MAX < code) return -1; #if ! ('$' == 0x24 && '@' == 0x40 && '`' == 0x60 && '~' == 0x7e) { /* A non-ASCII host. Use CODE to index into a table of the C basic execution character set, which is guaranteed to exist on all Standard C platforms. This table also includes '$', '@', and '`', which are not in the basic execution character set but which are unibyte characters on all the platforms that we know about. */ static signed char const table[] = { '\0', -1, -1, -1, -1, -1, -1, '\a', '\b', '\t', '\n', '\v', '\f', '\r', -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, ' ', '!', '"', '#', '$', '%', '&', '\'', '(', ')', '*', '+', ',', '-', '.', '/', '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', ':', ';', '<', '=', '>', '?', '@', 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z', '[', '\\', ']', '^', '_', '`', 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', '{', '|', '}', '~' }; code = code < sizeof table ? table[code] : -1; } #endif return code; } /*----------------------------------------------------------------. | Handle `#line INT "FILE"'. ARGS has already skipped `#line '. | `----------------------------------------------------------------*/ static void handle_syncline (char *args, location loc) { char *after_num; unsigned long int lineno = strtoul (args, &after_num, 10); char *file = strchr (after_num, '"') + 1; *strchr (file, '"') = '\0'; if (INT_MAX <= lineno) { warn_at (loc, _("line number overflow")); lineno = INT_MAX; } current_file = uniqstr_new (file); boundary_set (&scanner_cursor, current_file, lineno, 1); } /*----------------------------------------------------------------. | For a token or comment starting at START, report message MSGID, | | which should say that an end marker was found before | | the expected TOKEN_END. | `----------------------------------------------------------------*/ static void unexpected_end (boundary start, char const *msgid, char const *token_end) { location loc; loc.start = start; loc.end = scanner_cursor; complain_at (loc, _(msgid), token_end); } /*------------------------------------------------------------------------. | Report an unexpected EOF in a token or comment starting at START. | | An end of file was encountered and the expected TOKEN_END was missing. | `------------------------------------------------------------------------*/ static void unexpected_eof (boundary start, char const *token_end) { unexpected_end (start, N_("missing `%s' at end of file"), token_end); } /*----------------------------------------. | Likewise, but for unexpected newlines. | `----------------------------------------*/ static void unexpected_newline (boundary start, char const *token_end) { unexpected_end (start, N_("missing `%s' at end of line"), token_end); } /*-------------------------. | Initialize the scanner. | `-------------------------*/ void gram_scanner_initialize (void) { obstack_init (&obstack_for_string); } /*-----------------------------------------------. | Free all the memory allocated to the scanner. | `-----------------------------------------------*/ void gram_scanner_free (void) { obstack_free (&obstack_for_string, 0); /* Reclaim Flex's buffers. */ yylex_destroy (); }