X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/75d1fe16112a39706f26ac0d4d2784162e49f874..276f48df88293dc0a67237d1124a26e0f9ee82fb:/src/scan-gram.l diff --git a/src/scan-gram.l b/src/scan-gram.l index ddc50e19..cf704c77 100644 --- a/src/scan-gram.l +++ b/src/scan-gram.l @@ -1,5 +1,6 @@ /* Bison Grammar Scanner -*- C -*- - Copyright (C) 2002 Free Software Foundation, Inc. + + Copyright (C) 2002, 2003, 2004, 2005, 2006 Free Software Foundation, Inc. This file is part of Bison, the GNU Compiler Compiler. @@ -15,100 +16,201 @@ 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., 59 Temple Place, Suite 330, Boston, MA - 02111-1307 USA + Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA + 02110-1301 USA */ -%option debug nodefault noyywrap nounput never-interactive stack +%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 + #include "system.h" + +#include +#include + #include "complain.h" -#include "quote.h" +#include "files.h" #include "getargs.h" #include "gram.h" +#include "quotearg.h" #include "reader.h" - -/* Each time we match a string, move the end cursor to its end. */ -#define YY_USER_ACTION LOCATION_COLUMNS (*yylloc, yyleng) -#define YY_LINES LOCATION_LINES (*yylloc, yyleng); lineno += yyleng; -#define YY_STEP LOCATION_STEP (*yylloc) - - -/* STRING_OBSTACK -- Used to store all the characters that we need to +#include "uniqstr.h" + +#define YY_USER_INIT \ + do \ + { \ + scanner_cursor.file = current_file; \ + scanner_cursor.line = 1; \ + scanner_cursor.column = 1; \ + code_start = scanner_cursor; \ + } \ + while (0) + +/* Pacify "gcc -Wmissing-prototypes" when flex 2.5.31 is used. */ +int gram_get_lineno (void); +FILE *gram_get_in (void); +FILE *gram_get_out (void); +int gram_get_leng (void); +char *gram_get_text (void); +void gram_set_lineno (int); +void gram_set_in (FILE *); +void gram_set_out (FILE *); +int gram_get_debug (void); +void gram_set_debug (int); +int gram_lex_destroy (void); + +/* Location of scanner cursor. */ +boundary scanner_cursor; + +static void adjust_location (location *, char const *, size_t); +#define YY_USER_ACTION adjust_location (loc, 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)) + + +/* OBSTACK_FOR_STRING -- Used to store all the characters that we need to keep (to construct ID, STRINGS etc.). Use the following macros to use it. - Use YY_OBS_GROW to append what has just been matched, and - YY_OBS_FINISH to end the string (it puts the ending 0). - YY_OBS_FINISH also stores this string in LAST_STRING, which can be - used, and which is used by YY_OBS_FREE to free the last string. */ + Use STRING_GROW to append what has just been matched, and + STRING_FINISH to end the string (it puts the ending 0). + STRING_FINISH also stores this string in LAST_STRING, which can be + used, and which is used by STRING_FREE to free the last string. */ -static struct obstack string_obstack; +static struct obstack obstack_for_string; + +/* A string representing the most recently saved token. */ char *last_string; -#define YY_OBS_GROW \ - obstack_grow (&string_obstack, yytext, yyleng) +/* The location of the most recently saved token, if it was a + BRACED_CODE token; otherwise, this has an unspecified value. */ +location last_braced_code_loc; + +#define STRING_GROW \ + obstack_grow (&obstack_for_string, yytext, yyleng) -#define YY_OBS_FINISH \ +#define STRING_FINISH \ do { \ - obstack_1grow (&string_obstack, '\0'); \ - last_string = obstack_finish (&string_obstack); \ + obstack_1grow (&obstack_for_string, '\0'); \ + last_string = obstack_finish (&obstack_for_string); \ } while (0) -#define YY_OBS_FREE \ - do { \ - obstack_free (&string_obstack, last_string); \ - } while (0) +#define STRING_FREE \ + obstack_free (&obstack_for_string, last_string) void scanner_last_string_free (void) { - YY_OBS_FREE; + STRING_FREE; } +/* Within well-formed rules, RULE_LENGTH is the number of values in + the current rule so far, which says where to find `$0' with respect + to the top of the stack. It is not the same as the rule->length in + the case of mid rule actions. + + Outside of well-formed rules, RULE_LENGTH has an undefined value. */ +static int rule_length; -/* This is only to avoid GCC warnings. */ -#define YY_USER_INIT if (yycontrol) {;}; +static void rule_length_overflow (location) __attribute__ ((__noreturn__)); +/* Increment the rule length by one, checking for overflow. */ +static inline void +increment_rule_length (location loc) +{ + rule_length++; -static int braces_level = 0; -static int percent_percent_count = 0; + /* Don't allow rule_length == INT_MAX, since that might cause + confusion with strtol if INT_MAX == LONG_MAX. */ + if (rule_length == INT_MAX) + rule_length_overflow (loc); +} -static void handle_dollar PARAMS ((char *cp)); -static void handle_at PARAMS ((char *cp)); +static void handle_dollar (int token_type, char *cp, location loc); +static void handle_at (int token_type, char *cp, location 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); +static void unexpected_eof (boundary, char const *); +static void unexpected_newline (boundary, char const *); %} -%x SC_COMMENT +%x SC_COMMENT SC_LINE_COMMENT SC_YACC_COMMENT %x SC_STRING SC_CHARACTER +%x SC_AFTER_IDENTIFIER %x SC_ESCAPED_STRING SC_ESCAPED_CHARACTER -%x SC_BRACED_CODE SC_PROLOGUE SC_EPILOGUE +%x SC_PRE_CODE SC_BRACED_CODE SC_PROLOGUE SC_EPILOGUE -id [.a-zA-Z][.a-zA-Z_0-9]* -int [0-9]+ -eols (\n|\r|\n\r|\r\n)+ -blanks [ \t\f]+ +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)* %% %{ - /* At each yylex invocation, mark the current position as the - start of the next token. */ -#define TR_POS 0 -#if TR_POS - fprintf (stderr, "FOO1: "); - LOCATION_PRINT (stderr, *yylloc); - fprintf (stderr, "\n"); -#endif - YY_STEP; -#if TR_POS - fprintf (stderr, "BAR1: "); - LOCATION_PRINT (stderr, *yylloc); - fprintf (stderr, "\n"); -#endif + /* 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); + + /* 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); + + /* 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. | `----------------------------*/ @@ -116,21 +218,34 @@ blanks [ \t\f]+ { "%binary" return PERCENT_NONASSOC; "%debug" return PERCENT_DEBUG; + "%default"[-_]"prec" return PERCENT_DEFAULT_PREC; "%define" return PERCENT_DEFINE; "%defines" return PERCENT_DEFINES; + "%destructor" token_type = PERCENT_DESTRUCTOR; BEGIN SC_PRE_CODE; + "%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" token_type = PERCENT_INITIAL_ACTION; BEGIN SC_PRE_CODE; + "%glr-parser" return PERCENT_GLR_PARSER; "%left" return PERCENT_LEFT; + "%lex-param" token_type = PERCENT_LEX_PARAM; BEGIN SC_PRE_CODE; "%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; - "%prec" return PERCENT_PREC; + "%parse-param" token_type = PERCENT_PARSE_PARAM; BEGIN SC_PRE_CODE; + "%prec" rule_length--; return PERCENT_PREC; + "%printer" token_type = PERCENT_PRINTER; BEGIN SC_PRE_CODE; "%pure"[-_]"parser" return PERCENT_PURE_PARSER; + "%require" return PERCENT_REQUIRE; "%right" return PERCENT_RIGHT; "%skeleton" return PERCENT_SKELETON; "%start" return PERCENT_START; @@ -138,172 +253,192 @@ blanks [ \t\f]+ "%token" return PERCENT_TOKEN; "%token"[-_]"table" return PERCENT_TOKEN_TABLE; "%type" return PERCENT_TYPE; - "%union" return PERCENT_UNION; + "%union" token_type = PERCENT_UNION; BEGIN SC_PRE_CODE; "%verbose" return PERCENT_VERBOSE; "%yacc" return PERCENT_YACC; + {directive} { + complain_at (*loc, _("invalid directive: %s"), quote (yytext)); + } + "=" return EQUAL; - ":" return COLON; - "|" return PIPE; + "|" rule_length = 0; return PIPE; ";" return SEMICOLON; - {eols} YY_LINES; YY_STEP; - {blanks} YY_STEP; - {id} { - yylval->symbol = getsym (yytext); - return ID; + {id} { + val->symbol = symbol_get (yytext, *loc); + id_loc = *loc; + increment_rule_length (*loc); + BEGIN SC_AFTER_IDENTIFIER; } - {int} yylval->integer = strtol (yytext, 0, 10); return INT; + {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. */ - \' YY_OBS_GROW; yy_push_state (SC_ESCAPED_CHARACTER); + "'" STRING_GROW; token_start = loc->start; BEGIN SC_ESCAPED_CHARACTER; /* Strings. */ - \" YY_OBS_GROW; yy_push_state (SC_ESCAPED_STRING); - - /* Comments. */ - "/*" yy_push_state (SC_COMMENT); - "//".* YY_STEP; + "\"" token_start = loc->start; BEGIN SC_ESCAPED_STRING; /* Prologue. */ - "%{" yy_push_state (SC_PROLOGUE); + "%{" code_start = loc->start; BEGIN SC_PROLOGUE; /* Code in between braces. */ - "{" YY_OBS_GROW; ++braces_level; yy_push_state (SC_BRACED_CODE); + "{" { + if (current_rule && current_rule->action) + grammar_midrule_action (); + STRING_GROW; + token_type = BRACED_CODE; + braces_level = 0; + code_start = loc->start; + BEGIN SC_BRACED_CODE; + } /* A type. */ - "<"[^>]+">" { - obstack_grow (&string_obstack, yytext + 1, yyleng - 2); - YY_OBS_FINISH; - yylval->string = last_string; + "<"{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) - yy_push_state (SC_EPILOGUE); + BEGIN SC_EPILOGUE; return PERCENT_PERCENT; } - . { - LOCATION_PRINT (stderr, *yylloc); - fprintf (stderr, ": invalid character: `%c'\n", *yytext); - YY_STEP; + . { + complain_at (*loc, _("invalid character: %s"), quote (yytext)); + } + + <> { + loc->start = loc->end = scanner_cursor; + yyterminate (); } } - /*------------------------------------------------------------. - | Whatever the start condition (but those which correspond to | - | entity `swallowed' by Bison: SC_ESCAPED_STRING and | - | SC_ESCAPED_CHARACTER), no M4 character must escape as is. | - `------------------------------------------------------------*/ + /*-----------------------------------------------------------------. + | Scanning after an identifier, checking whether a colon is next. | + `-----------------------------------------------------------------*/ - + { - \[ if (YY_START != SC_COMMENT) obstack_sgrow (&string_obstack, "@<:@"); - \] if (YY_START != SC_COMMENT) obstack_sgrow (&string_obstack, "@:>@"); + ":" { + rule_length = 0; + *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. | + `---------------------------------------------------------------*/ - /*-----------------------------------------------------------. - | Scanning a C comment. The initial `/ *' is already eaten. | - `-----------------------------------------------------------*/ - - + { - "*/" { /* End of the comment. */ - if (yy_top_state () == INITIAL) - { - YY_STEP; - } - else - { - YY_OBS_GROW; - } - yy_pop_state (); - } + "*/" BEGIN context_state; + .|\n ; + <> unexpected_eof (token_start, "*/"); BEGIN context_state; +} - [^\[\]*\n\r]+ if (yy_top_state () != INITIAL) YY_OBS_GROW; - {eols} if (yy_top_state () != INITIAL) YY_OBS_GROW; YY_LINES; - . /* Stray `*'. */if (yy_top_state () != INITIAL) YY_OBS_GROW; - <> { - LOCATION_PRINT (stderr, *yylloc); - fprintf (stderr, ": unexpected end of file in a comment\n"); - yy_pop_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 C string, including its escapes. The initial `"' is | - | already eaten. | - `----------------------------------------------------------------*/ + /*--------------------------------------------------------------. + | Scanning a line comment. The initial `//' is already eaten. | + `--------------------------------------------------------------*/ - + { - \" { - assert (yy_top_state () == INITIAL); - YY_OBS_GROW; - YY_OBS_FINISH; - yylval->string = last_string; - yy_pop_state (); - return STRING; - } + "\n" STRING_GROW; BEGIN context_state; + {splice} STRING_GROW; + <> BEGIN context_state; +} - [^\"\n\r\\]+ YY_OBS_GROW; - {eols} obstack_1grow (&string_obstack, '\n'); YY_LINES; + /*------------------------------------------------. + | Scanning a Bison string, including its escapes. | + | The initial quote is already eaten. | + `------------------------------------------------*/ - <> { - LOCATION_PRINT (stderr, *yylloc); - fprintf (stderr, ": unexpected end of file in a string\n"); - assert (yy_top_state () == INITIAL); - YY_OBS_FINISH; - yylval->string = last_string; - yy_pop_state (); + +{ + "\"" { + STRING_FINISH; + loc->start = token_start; + val->chars = last_string; + increment_rule_length (*loc); + BEGIN INITIAL; return STRING; } + \n unexpected_newline (token_start, "\""); BEGIN INITIAL; + <> unexpected_eof (token_start, "\""); BEGIN INITIAL; } - /*---------------------------------------------------------------. - | Scanning a C character, decoding its escapes. The initial "'" | - | is already eaten. | - `---------------------------------------------------------------*/ + /*----------------------------------------------------------. + | Scanning a Bison character literal, decoding its escapes. | + | The initial quote is already eaten. | + `----------------------------------------------------------*/ { - \' { - YY_OBS_GROW; - assert (yy_top_state () == INITIAL); - { - YY_OBS_FINISH; - yylval->symbol = getsym (last_string); - symbol_class_set (yylval->symbol, token_sym); - symbol_user_token_number_set (yylval->symbol, last_string[1]); - YY_OBS_FREE; - yy_pop_state (); - return ID; - } + "'" { + unsigned char last_string_1; + 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); + STRING_FREE; + increment_rule_length (*loc); + BEGIN INITIAL; + return ID; } + \n unexpected_newline (token_start, "'"); BEGIN INITIAL; + <> unexpected_eof (token_start, "'"); BEGIN INITIAL; +} - [^\'\n\r\\] YY_OBS_GROW; - - {eols} obstack_1grow (&string_obstack, '\n'); YY_LINES; - - <> { - LOCATION_PRINT (stderr, *yylloc); - fprintf (stderr, ": unexpected end of file in a character\n"); - assert (yy_top_state () == INITIAL); - YY_OBS_FINISH; - yylval->string = last_string; - yy_pop_state (); - return CHARACTER; - } + +{ + \0 complain_at (*loc, _("invalid null character")); } @@ -313,89 +448,74 @@ blanks [ \t\f]+ { - \\[0-7]{3} { - long c = strtol (yytext + 1, 0, 8); - if (c > 255) - { - LOCATION_PRINT (stderr, *yylloc); - fprintf (stderr, ": invalid escape: %s\n", yytext); - YY_STEP; - } + \\[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 (&string_obstack, c); + obstack_1grow (&obstack_for_string, c); } - \\x[0-9a-fA-F]{2} { - obstack_1grow (&string_obstack, strtol (yytext + 2, 0, 16)); + \\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 (&string_obstack, '\a'); - \\b obstack_1grow (&string_obstack, '\b'); - \\f obstack_1grow (&string_obstack, '\f'); - \\n obstack_1grow (&string_obstack, '\n'); - \\r obstack_1grow (&string_obstack, '\r'); - \\t obstack_1grow (&string_obstack, '\t'); - \\v obstack_1grow (&string_obstack, '\v'); - \\[\\""] obstack_1grow (&string_obstack, yytext[1]); - \\. { - LOCATION_PRINT (stderr, *yylloc); - fprintf (stderr, ": unrecognized escape: %s\n", yytext); - YY_OBS_GROW; + \\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. | + `--------------------------------------------*/ - /*----------------------------------------------------------. - | Scanning a C character without decoding its escapes. The | - | initial "'" is already eaten. | - `----------------------------------------------------------*/ + +{ + {splice}|\\{splice}[^\n$@\[\]] STRING_GROW; +} { - \' { - YY_OBS_GROW; - assert (yy_top_state () != INITIAL); - yy_pop_state (); - } - - [^\[\]\'\n\r\\] YY_OBS_GROW; - \\. YY_OBS_GROW; - - {eols} YY_OBS_GROW; YY_LINES; - - <> { - LOCATION_PRINT (stderr, *yylloc); - fprintf (stderr, ": unexpected end of file in a character\n"); - assert (yy_top_state () != INITIAL); - yy_pop_state (); - } + "'" STRING_GROW; BEGIN context_state; + \n unexpected_newline (token_start, "'"); BEGIN context_state; + <> unexpected_eof (token_start, "'"); BEGIN context_state; } - - /*----------------------------------------------------------------. - | Scanning a C string, without decoding its escapes. The initial | - | `"' is already eaten. | - `----------------------------------------------------------------*/ - { - \" { - assert (yy_top_state () != INITIAL); - YY_OBS_GROW; - yy_pop_state (); - } - - [^\[\]\"\n\r\\]+ YY_OBS_GROW; - \\. YY_OBS_GROW; - - {eols} YY_OBS_GROW; YY_LINES; - - <> { - LOCATION_PRINT (stderr, *yylloc); - fprintf (stderr, ": unexpected end of file in a string\n"); - assert (yy_top_state () != INITIAL); - yy_pop_state (); - } + "\"" STRING_GROW; BEGIN context_state; + \n unexpected_newline (token_start, "\""); BEGIN context_state; + <> unexpected_eof (token_start, "\""); BEGIN context_state; } @@ -405,15 +525,64 @@ blanks [ \t\f]+ { - /* Characters. We don't check there is only one. */ - \' YY_OBS_GROW; yy_push_state (SC_CHARACTER); + "'" { + 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; + } +} - /* Strings. */ - \" YY_OBS_GROW; yy_push_state (SC_STRING); - /* Comments. */ - "/*" YY_OBS_GROW; yy_push_state (SC_COMMENT); - "//".* YY_OBS_GROW; + /*---------------------------------------------------------------. + | 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; } @@ -424,37 +593,59 @@ blanks [ \t\f]+ { + "{"|"<"{splice}"%" STRING_GROW; braces_level++; + "%"{splice}">" STRING_GROW; braces_level--; "}" { - YY_OBS_GROW; - if (--braces_level == 0) + bool outer_brace = --braces_level < 0; + + /* As an undocumented Bison extension, append `;' before the last + brace in braced code, so that the user code can omit trailing + `;'. But do not append `;' if emulating Yacc, since Yacc does + not append one. + + FIXME: Bison should warn if a semicolon seems to be necessary + here, and should omit the semicolon if it seems unnecessary + (e.g., after ';', '{', or '}', each followed by comments or + white space). Such a warning shouldn't depend on --yacc; it + should depend on a new --pedantic option, which would cause + Bison to warn if it detects an extension to POSIX. --pedantic + should also diagnose other Bison extensions like %yacc. + Perhaps there should also be a GCC-style --pedantic-errors + option, so that such warnings are diagnosed as errors. */ + if (outer_brace && token_type == BRACED_CODE && ! yacc_flag) + obstack_1grow (&obstack_for_string, ';'); + + obstack_1grow (&obstack_for_string, '}'); + + if (outer_brace) { - yy_pop_state (); - YY_OBS_FINISH; - yylval->string = last_string; - return BRACED_CODE; + STRING_FINISH; + loc->start = code_start; + val->chars = last_string; + increment_rule_length (*loc); + last_braced_code_loc = *loc; + BEGIN INITIAL; + return token_type; } } - "{" YY_OBS_GROW; braces_level++; - - "$"("<"[^>]+">")?(-?[0-9]+|"$") { handle_dollar (yytext); } - "@"(-?[0-9]+|"$") { handle_at (yytext); } + /* Tokenize `<<%' correctly (as `<<' `%') rather than incorrrectly + (as `<' `<%'). */ + "<"{splice}"<" STRING_GROW; - [^$@\[\]/\'\"\{\}\n\r]+ YY_OBS_GROW; - {eols} YY_OBS_GROW; YY_LINES; + "$"("<"{tag}">")?(-?[0-9]+|"$") handle_dollar (token_type, yytext, *loc); + "@"(-?[0-9]+|"$") handle_at (token_type, yytext, *loc); - /* A lose $, or /, or etc. */ - . YY_OBS_GROW; - - <> { - LOCATION_PRINT (stderr, *yylloc); - fprintf (stderr, ": unexpected end of file in a braced code\n"); - yy_pop_state (); - YY_OBS_FINISH; - yylval->string = last_string; - return BRACED_CODE; + "$" { + warn_at (*loc, _("stray `$'")); + obstack_sgrow (&obstack_for_string, "$]["); + } + "@" { + warn_at (*loc, _("stray `@'")); + obstack_sgrow (&obstack_for_string, "@@"); } + <> unexpected_eof (code_start, "}"); BEGIN INITIAL; } @@ -465,71 +656,192 @@ blanks [ \t\f]+ { "%}" { - yy_pop_state (); - YY_OBS_FINISH; - yylval->string = last_string; - return PROLOGUE; - } - - [^%\[\]/\'\"\n\r]+ YY_OBS_GROW; - "%"+[^%\}\n\r]+ YY_OBS_GROW; - {eols} YY_OBS_GROW; YY_LINES; - - <> { - LOCATION_PRINT (stderr, *yylloc); - fprintf (stderr, ": unexpected end of file in a prologue\n"); - yy_pop_state (); - YY_OBS_FINISH; - yylval->string = last_string; + STRING_FINISH; + loc->start = code_start; + val->chars = last_string; + BEGIN INITIAL; return PROLOGUE; } + <> unexpected_eof (code_start, "%}"); BEGIN INITIAL; } /*---------------------------------------------------------------. | Scanning the epilogue (everything after the second "%%", which | - | has already been eaten. | + | has already been eaten). | `---------------------------------------------------------------*/ { - ([^\[\]]|{eols})+ YY_OBS_GROW; - <> { - yy_pop_state (); - YY_OBS_FINISH; - yylval->string = last_string; + STRING_FINISH; + loc->start = code_start; + val->chars = last_string; + BEGIN INITIAL; return EPILOGUE; } } + /*-----------------------------------------. + | Escape M4 quoting characters in C code. | + `-----------------------------------------*/ + + +{ + \$ obstack_sgrow (&obstack_for_string, "$]["); + \@ obstack_sgrow (&obstack_for_string, "@@"); + \[ obstack_sgrow (&obstack_for_string, "@{"); + \] obstack_sgrow (&obstack_for_string, "@}"); +} + + + /*-----------------------------------------------------. + | By default, grow the string obstack with the input. | + `-----------------------------------------------------*/ + +. | +\n STRING_GROW; + %% +/* Keeps track of the maximum number of semantic values to the left of + a handle (those referenced by $0, $-1, etc.) are required by the + semantic actions of this grammar. */ +int max_left_semantic_context = 0; + +/* If BUF is null, add BUFSIZE (which in this case must be less than + INT_MAX) to COLUMN; otherwise, add mbsnwidth (BUF, BUFSIZE, 0) to + COLUMN. If an overflow occurs, or might occur but is undetectable, + return INT_MAX. Assume COLUMN is nonnegative. */ + +static inline int +add_column_width (int column, char const *buf, size_t bufsize) +{ + size_t width; + unsigned int remaining_columns = INT_MAX - column; + + if (buf) + { + if (INT_MAX / 2 <= bufsize) + return INT_MAX; + width = mbsnwidth (buf, bufsize, 0); + } + else + width = bufsize; + + return width <= remaining_columns ? column + width : INT_MAX; +} + +/* Set *LOC and adjust scanner cursor to account for token TOKEN of + size SIZE. */ + +static void +adjust_location (location *loc, char const *token, size_t size) +{ + int line = scanner_cursor.line; + int column = scanner_cursor.column; + char const *p0 = token; + char const *p = token; + char const *lim = token + size; + + loc->start = scanner_cursor; + + for (p = token; p < lim; p++) + switch (*p) + { + case '\n': + line += line < INT_MAX; + column = 1; + p0 = p + 1; + break; + + case '\t': + column = add_column_width (column, p0, p - p0); + column = add_column_width (column, NULL, 8 - ((column - 1) & 7)); + p0 = p + 1; + break; + + default: + break; + } + + scanner_cursor.line = line; + scanner_cursor.column = column = add_column_width (column, p0, p - p0); + + loc->end = scanner_cursor; + + if (line == INT_MAX && loc->start.line != INT_MAX) + warn_at (*loc, _("line number overflow")); + if (column == INT_MAX && loc->start.column != INT_MAX) + warn_at (*loc, _("column number overflow")); +} + + +/* 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; +} + + /*------------------------------------------------------------------. -| CP is pointing to a wannabee semantic value (i.e., a `$'). | +| TEXT is pointing to a wannabee semantic value (i.e., a `$'). | | | | Possible inputs: $[]($|integer) | | | -| Output to the STRING_OBSTACK a reference to this semantic value. | +| Output to OBSTACK_FOR_STRING a reference to this semantic value. | `------------------------------------------------------------------*/ -static void -handle_dollar (char *cp) +static inline bool +handle_action_dollar (char *text, location loc) { const char *type_name = NULL; + char *cp = text + 1; - /* RULE_LENGTH is the number of values in the current rule so far, - which says where to find `$0' with respect to the top of the - stack. It is not the same as the rule->length in the case of mid - rule actions. */ - int rule_length = 0; - symbol_list *rhs; - for (rhs = current_rule->next; rhs; rhs = rhs->next) - ++rule_length; - - ++cp; + if (! current_rule) + return false; /* Get the type name if explicit. */ if (*cp == '<') @@ -544,93 +856,312 @@ handle_dollar (char *cp) if (*cp == '$') { if (!type_name) - type_name = get_type_name (0, current_rule); + type_name = symbol_list_n_type_name_get (current_rule, loc, 0); if (!type_name && typed) - complain (_("$$ of `%s' has no declared type"), - current_rule->sym->tag); + complain_at (loc, _("$$ of `%s' has no declared type"), + current_rule->sym->tag); if (!type_name) type_name = ""; - obstack_fgrow1 (&string_obstack, + obstack_fgrow1 (&obstack_for_string, "]b4_lhs_value([%s])[", type_name); + current_rule->used = true; } - else if (isdigit (*cp) || *cp == '-') + else { - int n = strtol (cp, &cp, 10); + long int num = strtol (cp, NULL, 10); - if (n > rule_length) - complain (_("invalid value: %s%d"), "$", n); - else + if (1 - INT_MAX + rule_length <= num && num <= rule_length) { - if (!type_name && n > 0) - type_name = get_type_name (n, current_rule); + int n = num; + if (max_left_semantic_context < 1 - n) + max_left_semantic_context = 1 - n; + if (!type_name && 0 < n) + type_name = symbol_list_n_type_name_get (current_rule, loc, n); if (!type_name && typed) - complain (_("$%d of `%s' has no declared type"), - n, current_rule->sym->tag); + complain_at (loc, _("$%d of `%s' has no declared type"), + n, current_rule->sym->tag); if (!type_name) type_name = ""; - obstack_fgrow3 (&string_obstack, - "]b4_rhs_value([%d], [%d], [%s])[", + obstack_fgrow3 (&obstack_for_string, + "]b4_rhs_value(%d, %d, [%s])[", rule_length, n, type_name); + symbol_list_n_used_set (current_rule, n, true); } + else + complain_at (loc, _("integer out of range: %s"), quote (text)); } - else + + return true; +} + + +/*----------------------------------------------------------------. +| Map `$?' onto the proper M4 symbol, depending on its TOKEN_TYPE | +| (are we in an action?). | +`----------------------------------------------------------------*/ + +static void +handle_dollar (int token_type, char *text, location loc) +{ + switch (token_type) { - char buf[] = "$c"; - buf[1] = *cp; - complain (_("%s is invalid"), quote (buf)); + case BRACED_CODE: + if (handle_action_dollar (text, loc)) + return; + break; + + case PERCENT_DESTRUCTOR: + case PERCENT_INITIAL_ACTION: + case PERCENT_PRINTER: + if (text[1] == '$') + { + obstack_sgrow (&obstack_for_string, "]b4_dollar_dollar["); + return; + } + break; + + default: + break; } + + complain_at (loc, _("invalid value: %s"), quote (text)); } -/*-------------------------------------------------------. -| CP is pointing to a location (i.e., a `@'). Output to | -| STRING_OBSTACK a reference to this location. | -`-------------------------------------------------------*/ -static void -handle_at (char *cp) +/*------------------------------------------------------. +| TEXT is a location token (i.e., a `@...'). Output to | +| OBSTACK_FOR_STRING a reference to this location. | +`------------------------------------------------------*/ + +static inline bool +handle_action_at (char *text, location loc) { - /* RULE_LENGTH is the number of values in the current rule so far, - which says where to find `$0' with respect to the top of the - stack. It is not the same as the rule->length in the case of mid - rule actions. */ - int rule_length = 0; - symbol_list *rhs; - for (rhs = current_rule->next; rhs; rhs = rhs->next) - ++rule_length; + char *cp = text + 1; + locations_flag = true; - locations_flag = 1; - ++cp; + if (! current_rule) + return false; if (*cp == '$') + obstack_sgrow (&obstack_for_string, "]b4_lhs_location["); + else { - obstack_sgrow (&string_obstack, "]b4_lhs_location["); + long int num = strtol (cp, NULL, 10); + + if (1 - INT_MAX + rule_length <= num && num <= rule_length) + { + int n = num; + obstack_fgrow2 (&obstack_for_string, "]b4_rhs_location(%d, %d)[", + rule_length, n); + } + else + complain_at (loc, _("integer out of range: %s"), quote (text)); } - else if (isdigit (*cp) || *cp == '-') + + return true; +} + + +/*----------------------------------------------------------------. +| Map `@?' onto the proper M4 symbol, depending on its TOKEN_TYPE | +| (are we in an action?). | +`----------------------------------------------------------------*/ + +static void +handle_at (int token_type, char *text, location loc) +{ + switch (token_type) { - int n = strtol (cp, &cp, 10); - if (n > rule_length) - complain (_("invalid value: %s%d"), "@", n); - else - obstack_fgrow2 (&string_obstack, "]b4_rhs_location([%d], [%d])[", - rule_length, n); + case BRACED_CODE: + handle_action_at (text, loc); + return; + + case PERCENT_INITIAL_ACTION: + case PERCENT_DESTRUCTOR: + case PERCENT_PRINTER: + if (text[1] == '$') + { + obstack_sgrow (&obstack_for_string, "]b4_at_dollar["); + return; + } + break; + + default: + break; } - else + + complain_at (loc, _("invalid value: %s"), quote (text)); +} + + +/*------------------------------------------------------. +| Scan NUMBER for a base-BASE integer at location LOC. | +`------------------------------------------------------*/ + +static unsigned long int +scan_integer (char const *number, int base, location loc) +{ + verify (INT_MAX < ULONG_MAX); + unsigned long int num = strtoul (number, NULL, base); + + if (INT_MAX < num) { - char buf[] = "@c"; - buf[1] = *cp; - complain (_("%s is invalid"), quote (buf)); + complain_at (loc, _("integer out of range: %s"), quote (number)); + num = INT_MAX; } + + return num; } + +/*------------------------------------------------------------------. +| Convert universal character name UCN to a single-byte character, | +| and return that character. Return -1 if UCN does not correspond | +| to a single-byte character. | +`------------------------------------------------------------------*/ + +static int +convert_ucn_to_byte (char const *ucn) +{ + verify (UCHAR_MAX <= INT_MAX); + unsigned long int code = strtoul (ucn + 2, NULL, 16); + + /* FIXME: Currently we assume Unicode-compatible unibyte characters + on ASCII hosts (i.e., Latin-1 on hosts with 8-bit bytes). On + non-ASCII hosts we support only the portable C character set. + These limitations should be removed once we add support for + multibyte characters. */ + + if (UCHAR_MAX < code) + return -1; + +#if ! ('$' == 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; + } + scanner_cursor.file = current_file = uniqstr_new (file); + scanner_cursor.line = lineno; + scanner_cursor.column = 1; +} + + +/*---------------------------------. +| Report a rule that is too long. | +`---------------------------------*/ + +static void +rule_length_overflow (location loc) +{ + fatal_at (loc, _("rule is too long")); +} + + +/*----------------------------------------------------------------. +| 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 scanner_initialize (void) { - obstack_init (&string_obstack); + obstack_init (&obstack_for_string); } +/*-----------------------------------------------. +| Free all the memory allocated to the scanner. | +`-----------------------------------------------*/ + void scanner_free (void) { - obstack_free (&string_obstack, 0); + obstack_free (&obstack_for_string, 0); + /* Reclaim Flex's buffers. */ + yy_delete_buffer (YY_CURRENT_BUFFER); }