X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/e776192e4fcb3b34d8a279d7cc1ea153e96ae2e7..464c692789eba089bb21ebd3983ebeaa4a8d3312:/src/scan-gram.l diff --git a/src/scan-gram.l b/src/scan-gram.l index 02d47e5a..a2c61fd6 100644 --- a/src/scan-gram.l +++ b/src/scan-gram.l @@ -1,4 +1,5 @@ /* Bison Grammar Scanner -*- C -*- + Copyright (C) 2002 Free Software Foundation, Inc. This file is part of Bison, the GNU Compiler Compiler. @@ -19,101 +20,158 @@ 02111-1307 USA */ -%option debug nodefault noyywrap nounput never-interactive stack +%option debug nodefault noyywrap never-interactive %option prefix="gram_" outfile="lex.yy.c" %{ #include "system.h" + +#include <mbswidth.h> +#include <get-errno.h> +#include <quote.h> + #include "complain.h" -#include "quote.h" +#include "files.h" #include "getargs.h" #include "gram.h" #include "reader.h" +#include "uniqstr.h" + +#define YY_USER_INIT \ + do \ + { \ + scanner_cursor.file = current_file; \ + scanner_cursor.line = 1; \ + scanner_cursor.column = 1; \ + } \ + while (0) -/* Each time we match a string, move the end cursor to its end. */ -#define YY_USER_INIT \ -do { \ - LOCATION_RESET (*yylloc); \ - /* This is only to avoid GCC warnings. */ \ - if (yycontrol) {;}; \ -} while (0) +/* Location of scanner cursor. */ +boundary scanner_cursor; -#define YY_USER_ACTION LOCATION_COLUMNS (*yylloc, yyleng) -#define YY_LINES LOCATION_LINES (*yylloc, yyleng); lineno += yyleng; -#define YY_STEP LOCATION_STEP (*yylloc) +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)) -/* STRING_OBSTACK -- Used to store all the characters that we need to + +/* 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 obstack_for_string; + +/* A string representing the most recently saved token. */ +static char *last_string; -static struct obstack string_obstack; -char *last_string; -#define YY_OBS_GROW \ - obstack_grow (&string_obstack, yytext, yyleng) +#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. -static int braces_level = 0; -static int percent_percent_count = 0; + Outside of well-formed rules, RULE_LENGTH has an undefined value. */ +static int rule_length; -static void handle_dollar PARAMS ((braced_code_t code_kind, - char *cp, location_t location)); -static void handle_at PARAMS ((braced_code_t code_kind, - char *cp, location_t location)); +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 *args); +static int convert_ucn_to_byte (char const *hex_text); +static void unexpected_end_of_file (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 + +letter [.abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ_] +id {letter}({letter}|[0-9])* +directive %{letter}({letter}|[0-9]|-)* +int [0-9]+ -id [.a-zA-Z][.a-zA-Z_0-9]* -int [0-9]+ -eols (\n|\r|\n\r|\r\n)+ -blanks [ \t\f]+ +/* 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: %p: ", yylloc); - 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 (= *loc); + + /* Where containing code started, when applicable. */ + boundary code_start IF_LINT (= loc->start); + + /* Where containing comment or string or character literal started, + when applicable. */ + boundary token_start IF_LINT (= loc->start); %} + /*-----------------------. + | Scanning white space. | + `-----------------------*/ + +<INITIAL,SC_AFTER_IDENTIFIER,SC_PRE_CODE> +{ + [ \f\n\t\v] ; + "," warn_at (*loc, _("stray `,' treated as white space")); + + /* Comments. */ + "//".* ; + "/*" { + 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); + } +} + + /*----------------------------. | Scanning Bison directives. | `----------------------------*/ @@ -123,20 +181,25 @@ blanks [ \t\f]+ "%debug" return PERCENT_DEBUG; "%define" return PERCENT_DEFINE; "%defines" return PERCENT_DEFINES; - "%destructor" return PERCENT_DESTRUCTOR; + "%destructor" token_type = PERCENT_DESTRUCTOR; BEGIN SC_PRE_CODE; + "%dprec" return PERCENT_DPREC; "%error"[-_]"verbose" return PERCENT_ERROR_VERBOSE; "%expect" return PERCENT_EXPECT; "%file-prefix" return PERCENT_FILE_PREFIX; "%fixed"[-_]"output"[-_]"files" return PERCENT_YACC; + "%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"[-_]"lines" return PERCENT_NO_LINES; "%nonassoc" return PERCENT_NONASSOC; "%nterm" return PERCENT_NTERM; "%output" return PERCENT_OUTPUT; - "%prec" return PERCENT_PREC; - "%printer" return PERCENT_PRINTER; + "%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; "%right" return PERCENT_RIGHT; "%skeleton" return PERCENT_SKELETON; @@ -145,104 +208,140 @@ 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, *yylloc); - return ID; + {id} { + val->symbol = symbol_get (yytext, *loc); + id_loc = *loc; + rule_length++; + BEGIN SC_AFTER_IDENTIFIER; } - {int} yylval->integer = strtol (yytext, 0, 10); return INT; + {int} { + unsigned long num; + set_errno (0); + num = strtoul (yytext, 0, 10); + if (INT_MAX < num || get_errno ()) + { + complain_at (*loc, _("integer out of range: %s"), quote (yytext)); + num = INT_MAX; + } + val->integer = num; + 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; + "\"" STRING_GROW; 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); + "{" { + 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); + { + code_start = loc->start; + 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)); } } - /*------------------------------------------------------------. - | 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. | + `-----------------------------------------------------------------*/ -<SC_COMMENT,SC_STRING,SC_CHARACTER,SC_BRACED_CODE,SC_PROLOGUE,SC_EPILOGUE> +<SC_AFTER_IDENTIFIER> { - \[ if (YY_START != SC_COMMENT) obstack_sgrow (&string_obstack, "@<:@"); - \] 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; + } + <<EOF>> { + *loc = id_loc; + BEGIN INITIAL; + return ID; + } } + /*---------------------------------------------------------------. + | Scanning a Yacc comment. The initial `/ *' is already eaten. | + `---------------------------------------------------------------*/ + +<SC_YACC_COMMENT> +{ + "*/" BEGIN context_state; + .|\n ; + <<EOF>> unexpected_end_of_file (token_start, "*/"); +} + - /*-----------------------------------------------------------. - | Scanning a C comment. The initial `/ *' is already eaten. | - `-----------------------------------------------------------*/ + /*------------------------------------------------------------. + | Scanning a C comment. The initial `/ *' is already eaten. | + `------------------------------------------------------------*/ <SC_COMMENT> { - "*/" { /* End of the comment. */ - if (yy_top_state () == INITIAL) - { - YY_STEP; - } - else - { - YY_OBS_GROW; - } - yy_pop_state (); - } + "*"{splice}"/" STRING_GROW; BEGIN context_state; + <<EOF>> unexpected_end_of_file (token_start, "*/"); +} - [^\[\]*\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; - <<EOF>> { - LOCATION_PRINT (stderr, *yylloc); - fprintf (stderr, ": unexpected end of file in a comment\n"); - yy_pop_state (); - } + /*--------------------------------------------------------------. + | Scanning a line comment. The initial `//' is already eaten. | + `--------------------------------------------------------------*/ + +<SC_LINE_COMMENT> +{ + "\n" STRING_GROW; BEGIN context_state; + {splice} STRING_GROW; + <<EOF>> BEGIN context_state; } @@ -253,28 +352,18 @@ blanks [ \t\f]+ <SC_ESCAPED_STRING> { - \" { - assert (yy_top_state () == INITIAL); - YY_OBS_GROW; - YY_OBS_FINISH; - yylval->string = last_string; - yy_pop_state (); + "\"" { + STRING_GROW; + STRING_FINISH; + loc->start = token_start; + val->chars = last_string; + rule_length++; + BEGIN INITIAL; return STRING; } - [^\"\n\r\\]+ YY_OBS_GROW; - - {eols} obstack_1grow (&string_obstack, '\n'); YY_LINES; - - <<EOF>> { - 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 (); - return STRING; - } + .|\n STRING_GROW; + <<EOF>> unexpected_end_of_file (token_start, "\""); } /*---------------------------------------------------------------. @@ -284,33 +373,23 @@ blanks [ \t\f]+ <SC_ESCAPED_CHARACTER> { - \' { - YY_OBS_GROW; - assert (yy_top_state () == INITIAL); - { - YY_OBS_FINISH; - yylval->symbol = getsym (last_string, *yylloc); - symbol_class_set (yylval->symbol, token_sym, *yylloc); - symbol_user_token_number_set (yylval->symbol, last_string[1], *yylloc); - 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 (last_string, *loc); + symbol_class_set (val->symbol, token_sym, *loc); + last_string_1 = last_string[1]; + symbol_user_token_number_set (val->symbol, last_string_1, *loc); + STRING_FREE; + rule_length++; + BEGIN INITIAL; + return ID; } - [^\'\n\r\\] YY_OBS_GROW; - - {eols} obstack_1grow (&string_obstack, '\n'); YY_LINES; - - <<EOF>> { - 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; - } + .|\n STRING_GROW; + <<EOF>> unexpected_end_of_file (token_start, "'"); } @@ -320,37 +399,46 @@ blanks [ \t\f]+ <SC_ESCAPED_STRING,SC_ESCAPED_CHARACTER> { - \\[0-7]{3} { - long c = strtol (yytext + 1, 0, 8); - if (c > 255) - { - LOCATION_PRINT (stderr, *yylloc); - fprintf (stderr, ": invalid escape: %s\n", quote (yytext)); - YY_STEP; - } + \\[0-7]{1,3} { + unsigned long c = strtoul (yytext + 1, 0, 8); + if (UCHAR_MAX < c) + complain_at (*loc, _("invalid escape sequence: %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]+ { + unsigned long c; + set_errno (0); + c = strtoul (yytext + 2, 0, 16); + if (UCHAR_MAX < c || get_errno ()) + complain_at (*loc, _("invalid escape sequence: %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]); + \\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 + obstack_1grow (&obstack_for_string, c); + } \\(.|\n) { - LOCATION_PRINT (stderr, *yylloc); - fprintf (stderr, ": unrecognized escape: %s\n", quote (yytext)); - YY_OBS_GROW; + complain_at (*loc, _("unrecognized escape sequence: %s"), quote (yytext)); + STRING_GROW; } - /* FLex wants this rule, in case of a `\<<EOF>>'. */ - \\ YY_OBS_GROW; } @@ -361,25 +449,9 @@ blanks [ \t\f]+ <SC_CHARACTER> { - \' { - YY_OBS_GROW; - assert (yy_top_state () != INITIAL); - yy_pop_state (); - } - - [^\[\]\'\n\r\\]+ YY_OBS_GROW; - \\(.|\n) YY_OBS_GROW; - /* FLex wants this rule, in case of a `\<<EOF>>'. */ - \\ YY_OBS_GROW; - - {eols} YY_OBS_GROW; YY_LINES; - - <<EOF>> { - 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; + \\{splice}[^$@\[\]] STRING_GROW; + <<EOF>> unexpected_end_of_file (token_start, "'"); } @@ -390,25 +462,9 @@ blanks [ \t\f]+ <SC_STRING> { - \" { - assert (yy_top_state () != INITIAL); - YY_OBS_GROW; - yy_pop_state (); - } - - [^\[\]\"\n\r\\]+ YY_OBS_GROW; - \\(.|\n) YY_OBS_GROW; - /* FLex wants this rule, in case of a `\<<EOF>>'. */ - \\ YY_OBS_GROW; - - {eols} YY_OBS_GROW; YY_LINES; - - <<EOF>> { - 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; + \\{splice}[^$@\[\]] STRING_GROW; + <<EOF>> unexpected_end_of_file (token_start, "\""); } @@ -418,18 +474,62 @@ blanks [ \t\f]+ <SC_BRACED_CODE,SC_PROLOGUE,SC_EPILOGUE> { - /* 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. | + `---------------------------------------------------------------*/ + +<SC_PRE_CODE> +{ + . { + bool valid = yytext[0] == '{' || token_type == PERCENT_UNION; + scanner_cursor.column -= mbsnwidth (yytext, yyleng, 0); + yyless (0); - /* Not comments. */ - "/" YY_OBS_GROW; + 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; + } + } } @@ -440,39 +540,49 @@ blanks [ \t\f]+ <SC_BRACED_CODE> { + "{"|"<"{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; + rule_length++; + loc->start = code_start; + val->chars = last_string; + BEGIN INITIAL; + return token_type; } } - "{" YY_OBS_GROW; braces_level++; - - "$"("<"[^>]+">")?(-?[0-9]+|"$") { handle_dollar (current_braced_code, - yytext, *yylloc); } - "@"(-?[0-9]+|"$") { handle_at (current_braced_code, - yytext, *yylloc); } - - [^$@\[\]/\'\"\{\}\n\r]+ YY_OBS_GROW; - {eols} YY_OBS_GROW; YY_LINES; - - /* A lose $, or /, or etc. */ - . YY_OBS_GROW; + /* Tokenize `<<%' correctly (as `<<' `%') rather than incorrrectly + (as `<' `<%'). */ + "<"{splice}"<" STRING_GROW; - <<EOF>> { - LOCATION_PRINT (stderr, *yylloc); - fprintf (stderr, ": unexpected end of file in a braced code\n"); - yy_pop_state (); - YY_OBS_FINISH; - yylval->string = last_string; - return BRACED_CODE; - } + "$"("<"{tag}">")?(-?[0-9]+|"$") handle_dollar (token_type, yytext, *loc); + "@"(-?[0-9]+|"$") handle_at (token_type, yytext, *loc); + <<EOF>> unexpected_end_of_file (code_start, "}"); } @@ -483,61 +593,152 @@ blanks [ \t\f]+ <SC_PROLOGUE> { "%}" { - yy_pop_state (); - YY_OBS_FINISH; - yylval->string = last_string; + STRING_FINISH; + loc->start = code_start; + val->chars = last_string; + BEGIN INITIAL; return PROLOGUE; } - [^%\[\]/\'\"\n\r]+ YY_OBS_GROW; - "%" YY_OBS_GROW; - {eols} YY_OBS_GROW; YY_LINES; - - <<EOF>> { - LOCATION_PRINT (stderr, *yylloc); - fprintf (stderr, ": unexpected end of file in a prologue\n"); - yy_pop_state (); - YY_OBS_FINISH; - yylval->string = last_string; - return PROLOGUE; - } + <<EOF>> unexpected_end_of_file (code_start, "%}"); } /*---------------------------------------------------------------. | Scanning the epilogue (everything after the second "%%", which | - | has already been eaten. | + | has already been eaten). | `---------------------------------------------------------------*/ <SC_EPILOGUE> { - ([^\[\]]|{eols})+ YY_OBS_GROW; - <<EOF>> { - yy_pop_state (); - YY_OBS_FINISH; - yylval->string = last_string; + STRING_FINISH; + loc->start = code_start; + val->chars = last_string; + BEGIN INITIAL; return EPILOGUE; } } + /*----------------------------------------------------------------. + | By default, grow the string obstack with the input, escaping M4 | + | quoting characters. | + `----------------------------------------------------------------*/ + +<SC_COMMENT,SC_LINE_COMMENT,SC_STRING,SC_CHARACTER,SC_BRACED_CODE,SC_PROLOGUE,SC_EPILOGUE> +{ + \$ obstack_sgrow (&obstack_for_string, "$]["); + \@ obstack_sgrow (&obstack_for_string, "@@"); + \[ obstack_sgrow (&obstack_for_string, "@{"); + \] obstack_sgrow (&obstack_for_string, "@}"); + .|\n STRING_GROW; +} + + %% +/* 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++; + column = 1; + p0 = p + 1; + break; + + case '\t': + column += mbsnwidth (p0, p - p0, 0); + column += 8 - ((column - 1) & 7); + p0 = p + 1; + break; + } + + scanner_cursor.line = line; + scanner_cursor.column = column + mbsnwidth (p0, p - p0, 0); + + loc->end = scanner_cursor; +} + + +/* 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 s = fread (buf, 1, size, fp); + if (s) + { + char *w = memchr (buf, '\r', s); + if (w) + { + char const *r = ++w; + char const *lim = buf + s; + + 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 s; +} + + /*------------------------------------------------------------------. | TEXT is pointing to a wannabee semantic value (i.e., a `$'). | | | | Possible inputs: $[<TYPENAME>]($|integer) | | | -| Output to the STRING_OBSTACK a reference to this semantic value. | +| Output to OBSTACK_FOR_STRING a reference to this semantic value. | `------------------------------------------------------------------*/ -static inline void -handle_action_dollar (char *text, location_t location) +static inline bool +handle_action_dollar (char *text, location loc) { const char *type_name = NULL; char *cp = text + 1; + if (! current_rule) + return false; + /* Get the type name if explicit. */ if (*cp == '<') { @@ -551,137 +752,108 @@ handle_action_dollar (char *text, location_t location) if (*cp == '$') { if (!type_name) - type_name = symbol_list_n_type_name_get (current_rule, location, 0); + type_name = symbol_list_n_type_name_get (current_rule, loc, 0); if (!type_name && typed) - complain_at (location, _("$$ of `%s' has no declared type"), - symbol_tag_get (current_rule->sym)); + complain_at (loc, _("$$ 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); } - else if (isdigit (*cp) || *cp == '-') + else { - /* RULE_LENGTH is the number of values in the current rule so - far, which says where to find `$0' with respect to the top of - the stack. It is not the same as the rule->length in the - case of mid rule actions. */ - int rule_length = symbol_list_length (current_rule->next); - int n = strtol (cp, &cp, 10); - - if (n > rule_length) - complain_at (location, _("invalid value: %s%d"), "$", n); - else + long num; + set_errno (0); + num = strtol (cp, 0, 10); + + if (INT_MIN <= num && num <= rule_length && ! get_errno ()) { + int n = num; if (!type_name && n > 0) - type_name = symbol_list_n_type_name_get (current_rule, location, - n); + type_name = symbol_list_n_type_name_get (current_rule, loc, n); if (!type_name && typed) - complain_at (location, _("$%d of `%s' has no declared type"), - n, symbol_tag_get (current_rule->sym)); + complain_at (loc, _("$%d of `%s' has no declared type"), + n, current_rule->sym->tag); if (!type_name) type_name = ""; - obstack_fgrow3 (&string_obstack, + obstack_fgrow3 (&obstack_for_string, "]b4_rhs_value([%d], [%d], [%s])[", rule_length, n, type_name); } + else + complain_at (loc, _("integer out of range: %s"), quote (text)); } - else - { - complain_at (location, _("%s is invalid"), quote (text)); - } -} - -/*---------------------------------------------------------------. -| TEXT is expexted tp be $$ in some code associated to a symbol: | -| destructor or printer. | -`---------------------------------------------------------------*/ - -static inline void -handle_symbol_code_dollar (char *text, location_t location) -{ - char *cp = text + 1; - if (*cp == '$') - obstack_sgrow (&string_obstack, "]b4_dollar_dollar["); - else - complain_at (location, _("%s is invalid"), quote (text)); + return true; } /*-----------------------------------------------------------------. | Dispatch onto handle_action_dollar, or handle_destructor_dollar, | -| depending upon CODE_KIND. | +| depending upon TOKEN_TYPE. | `-----------------------------------------------------------------*/ static void -handle_dollar (braced_code_t braced_code_kind, - char *text, location_t location) +handle_dollar (int token_type, char *text, location loc) { - switch (braced_code_kind) + switch (token_type) { - case action_braced_code: - handle_action_dollar (text, location); + case BRACED_CODE: + if (handle_action_dollar (text, loc)) + return; + break; + + case PERCENT_DESTRUCTOR: + case PERCENT_PRINTER: + if (text[1] == '$') + { + obstack_sgrow (&obstack_for_string, "]b4_dollar_dollar["); + return; + } break; - case destructor_braced_code: - case printer_braced_code: - handle_symbol_code_dollar (text, location); + default: break; } + + complain_at (loc, _("invalid value: %s"), quote (text)); } /*------------------------------------------------------. | TEXT is a location token (i.e., a `@...'). Output to | -| STRING_OBSTACK a reference to this location. | +| OBSTACK_FOR_STRING a reference to this location. | `------------------------------------------------------*/ -static inline void -handle_action_at (char *text, location_t location) +static inline bool +handle_action_at (char *text, location loc) { char *cp = text + 1; locations_flag = 1; + if (! current_rule) + return false; + if (*cp == '$') - { - obstack_sgrow (&string_obstack, "]b4_lhs_location["); - } - else if (isdigit (*cp) || *cp == '-') - { - /* RULE_LENGTH is the number of values in the current rule so - far, which says where to find `$0' with respect to the top of - the stack. It is not the same as the rule->length in the - case of mid rule actions. */ - int rule_length = symbol_list_length (current_rule->next); - int n = strtol (cp, &cp, 10); - - if (n > rule_length) - complain_at (location, _("invalid value: %s%d"), "@", n); - else - obstack_fgrow2 (&string_obstack, "]b4_rhs_location([%d], [%d])[", - rule_length, n); - } + obstack_sgrow (&obstack_for_string, "]b4_lhs_location["); else { - complain_at (location, _("%s is invalid"), quote (text)); - } -} + long num; + set_errno (0); + num = strtol (cp, 0, 10); + if (INT_MIN <= num && num <= rule_length && ! get_errno ()) + { + int n = num; + obstack_fgrow2 (&obstack_for_string, "]b4_rhs_location([%d], [%d])[", + rule_length, n); + } + else + complain_at (loc, _("integer out of range: %s"), quote (text)); + } -/*---------------------------------------------------------------. -| TEXT is expexted tp be @$ in some code associated to a symbol: | -| destructor or printer. | -`---------------------------------------------------------------*/ - -static inline void -handle_symbol_code_at (char *text, location_t location) -{ - char *cp = text + 1; - if (*cp == '$') - obstack_sgrow (&string_obstack, "]b4_at_dollar["); - else - complain_at (location, _("%s is invalid"), quote (text)); + return true; } @@ -691,20 +863,126 @@ handle_symbol_code_at (char *text, location_t location) `-------------------------------------------------------------------*/ static void -handle_at (braced_code_t braced_code_kind, - char *text, location_t location) +handle_at (int token_type, char *text, location loc) { - switch (braced_code_kind) + switch (token_type) { - case action_braced_code: - handle_action_at (text, location); + case BRACED_CODE: + handle_action_at (text, loc); + return; + + case PERCENT_DESTRUCTOR: + case PERCENT_PRINTER: + if (text[1] == '$') + { + obstack_sgrow (&obstack_for_string, "]b4_at_dollar["); + return; + } break; - case destructor_braced_code: - case printer_braced_code: - handle_symbol_code_at (text, location); + default: break; } + + complain_at (loc, _("invalid value: %s"), quote (text)); +} + + +/*------------------------------------------------------------------. +| 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) +{ + unsigned long code = strtoul (ucn + 2, 0, 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) +{ + int lineno = strtol (args, &args, 10); + const char *file = NULL; + file = strchr (args, '"') + 1; + *strchr (file, '"') = 0; + scanner_cursor.file = current_file = xstrdup (file); + scanner_cursor.line = lineno; + scanner_cursor.column = 1; +} + + +/*------------------------------------------------------------------------. +| 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. | +| After reporting the problem, pretend that TOKEN_END was found. | +`------------------------------------------------------------------------*/ + +static void +unexpected_end_of_file (boundary start, char const *token_end) +{ + size_t i = strlen (token_end); + + location loc; + loc.start = start; + loc.end = scanner_cursor; + complain_at (loc, _("missing `%s' at end of file"), token_end); + + /* Adjust scanner cursor so that any later message does not count + the characters about to be inserted. */ + scanner_cursor.column -= i; + + while (i != 0) + unput (token_end[--i]); } @@ -715,7 +993,7 @@ handle_at (braced_code_t braced_code_kind, void scanner_initialize (void) { - obstack_init (&string_obstack); + obstack_init (&obstack_for_string); } @@ -726,5 +1004,7 @@ scanner_initialize (void) 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); }