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Diffstat (limited to 'src/scan-gram.l')
| -rw-r--r-- | src/scan-gram.l | 1167 |
1 files changed, 1167 insertions, 0 deletions
diff --git a/src/scan-gram.l b/src/scan-gram.l new file mode 100644 index 00000000..cf704c77 --- /dev/null +++ b/src/scan-gram.l @@ -0,0 +1,1167 @@ +/* Bison Grammar Scanner -*- C -*- + + Copyright (C) 2002, 2003, 2004, 2005, 2006 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 2 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, write to the Free Software + Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA + 02110-1301 USA +*/ + +%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 + <http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=333231>. */ +#undef gram_wrap +#define gram_wrap() 1 + +#include "system.h" + +#include <mbswidth.h> +#include <quote.h> + +#include "complain.h" +#include "files.h" +#include "getargs.h" +#include "gram.h" +#include "quotearg.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; \ + 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 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. */ +char *last_string; + +/* 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 STRING_FINISH \ + do { \ + obstack_1grow (&obstack_for_string, '\0'); \ + last_string = obstack_finish (&obstack_for_string); \ + } while (0) + +#define STRING_FREE \ + obstack_free (&obstack_for_string, last_string) + +void +scanner_last_string_free (void) +{ + 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; + +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++; + + /* 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 (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 SC_LINE_COMMENT SC_YACC_COMMENT +%x SC_STRING SC_CHARACTER +%x SC_AFTER_IDENTIFIER +%x SC_ESCAPED_STRING SC_ESCAPED_CHARACTER +%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]+ + +/* 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); + + /* 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. | + `-----------------------*/ + +<INITIAL,SC_AFTER_IDENTIFIER,SC_PRE_CODE> +{ + /* 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. | + `----------------------------*/ +<INITIAL> +{ + "%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; + "%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; + "%term" return PERCENT_TOKEN; + "%token" return PERCENT_TOKEN; + "%token"[-_]"table" return PERCENT_TOKEN_TABLE; + "%type" return PERCENT_TYPE; + "%union" token_type = PERCENT_UNION; BEGIN SC_PRE_CODE; + "%verbose" return PERCENT_VERBOSE; + "%yacc" return PERCENT_YACC; + + {directive} { + complain_at (*loc, _("invalid directive: %s"), quote (yytext)); + } + + "=" return EQUAL; + "|" rule_length = 0; return PIPE; + ";" return SEMICOLON; + + {id} { + val->symbol = symbol_get (yytext, *loc); + id_loc = *loc; + increment_rule_length (*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. */ + "{" { + 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. */ + "<"{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)); + } + + <<EOF>> { + loc->start = loc->end = scanner_cursor; + yyterminate (); + } +} + + + /*-----------------------------------------------------------------. + | Scanning after an identifier, checking whether a colon is next. | + `-----------------------------------------------------------------*/ + +<SC_AFTER_IDENTIFIER> +{ + ":" { + 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_eof (token_start, "*/"); BEGIN context_state; +} + + + /*------------------------------------------------------------. + | Scanning a C comment. The initial `/ *' is already eaten. | + `------------------------------------------------------------*/ + +<SC_COMMENT> +{ + "*"{splice}"/" STRING_GROW; BEGIN context_state; + <<EOF>> unexpected_eof (token_start, "*/"); BEGIN context_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; +} + + + /*------------------------------------------------. + | Scanning a Bison string, including its escapes. | + | The initial quote is already eaten. | + `------------------------------------------------*/ + +<SC_ESCAPED_STRING> +{ + "\"" { + 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; + <<EOF>> unexpected_eof (token_start, "\""); BEGIN INITIAL; +} + + /*----------------------------------------------------------. + | Scanning a Bison character literal, decoding its escapes. | + | The initial quote is already eaten. | + `----------------------------------------------------------*/ + +<SC_ESCAPED_CHARACTER> +{ + "'" { + 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; + <<EOF>> unexpected_eof (token_start, "'"); BEGIN INITIAL; +} + +<SC_ESCAPED_CHARACTER,SC_ESCAPED_STRING> +{ + \0 complain_at (*loc, _("invalid null character")); +} + + + /*----------------------------. + | Decode escaped characters. | + `----------------------------*/ + +<SC_ESCAPED_STRING,SC_ESCAPED_CHARACTER> +{ + \\[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. | + `--------------------------------------------*/ + +<SC_CHARACTER,SC_STRING> +{ + {splice}|\\{splice}[^\n$@\[\]] STRING_GROW; +} + +<SC_CHARACTER> +{ + "'" STRING_GROW; BEGIN context_state; + \n unexpected_newline (token_start, "'"); BEGIN context_state; + <<EOF>> unexpected_eof (token_start, "'"); BEGIN context_state; +} + +<SC_STRING> +{ + "\"" STRING_GROW; BEGIN context_state; + \n unexpected_newline (token_start, "\""); BEGIN context_state; + <<EOF>> unexpected_eof (token_start, "\""); BEGIN context_state; +} + + + /*---------------------------------------------------. + | Strings, comments etc. can be found in user code. | + `---------------------------------------------------*/ + +<SC_BRACED_CODE,SC_PROLOGUE,SC_EPILOGUE> +{ + "'" { + 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 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); + + 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; + } + } + + <<EOF>> unexpected_eof (scanner_cursor, "{}"); BEGIN INITIAL; +} + + + /*---------------------------------------------------------------. + | Scanning some code in braces (%union and actions). The initial | + | "{" is already eaten. | + `---------------------------------------------------------------*/ + +<SC_BRACED_CODE> +{ + "{"|"<"{splice}"%" STRING_GROW; braces_level++; + "%"{splice}">" STRING_GROW; braces_level--; + "}" { + 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) + { + STRING_FINISH; + loc->start = code_start; + val->chars = last_string; + increment_rule_length (*loc); + last_braced_code_loc = *loc; + BEGIN INITIAL; + return token_type; + } + } + + /* Tokenize `<<%' correctly (as `<<' `%') rather than incorrrectly + (as `<' `<%'). */ + "<"{splice}"<" STRING_GROW; + + "$"("<"{tag}">")?(-?[0-9]+|"$") handle_dollar (token_type, yytext, *loc); + "@"(-?[0-9]+|"$") handle_at (token_type, yytext, *loc); + + "$" { + warn_at (*loc, _("stray `$'")); + obstack_sgrow (&obstack_for_string, "$]["); + } + "@" { + warn_at (*loc, _("stray `@'")); + obstack_sgrow (&obstack_for_string, "@@"); + } + + <<EOF>> unexpected_eof (code_start, "}"); BEGIN INITIAL; +} + + + /*--------------------------------------------------------------. + | Scanning some prologue: from "%{" (already scanned) to "%}". | + `--------------------------------------------------------------*/ + +<SC_PROLOGUE> +{ + "%}" { + STRING_FINISH; + loc->start = code_start; + val->chars = last_string; + BEGIN INITIAL; + return PROLOGUE; + } + + <<EOF>> unexpected_eof (code_start, "%}"); BEGIN INITIAL; +} + + + /*---------------------------------------------------------------. + | Scanning the epilogue (everything after the second "%%", which | + | has already been eaten). | + `---------------------------------------------------------------*/ + +<SC_EPILOGUE> +{ + <<EOF>> { + STRING_FINISH; + loc->start = code_start; + val->chars = last_string; + BEGIN INITIAL; + return EPILOGUE; + } +} + + + /*-----------------------------------------. + | Escape M4 quoting characters in C code. | + `-----------------------------------------*/ + +<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, "@}"); +} + + + /*-----------------------------------------------------. + | By default, grow the string obstack with the input. | + `-----------------------------------------------------*/ + +<SC_COMMENT,SC_LINE_COMMENT,SC_BRACED_CODE,SC_PROLOGUE,SC_EPILOGUE,SC_STRING,SC_CHARACTER,SC_ESCAPED_STRING,SC_ESCAPED_CHARACTER>. | +<SC_COMMENT,SC_LINE_COMMENT,SC_BRACED_CODE,SC_PROLOGUE,SC_EPILOGUE>\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; +} + + +/*------------------------------------------------------------------. +| TEXT is pointing to a wannabee semantic value (i.e., a `$'). | +| | +| Possible inputs: $[<TYPENAME>]($|integer) | +| | +| Output to OBSTACK_FOR_STRING a reference to this semantic value. | +`------------------------------------------------------------------*/ + +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 == '<') + { + type_name = ++cp; + while (*cp != '>') + ++cp; + *cp = '\0'; + ++cp; + } + + if (*cp == '$') + { + if (!type_name) + type_name = symbol_list_n_type_name_get (current_rule, loc, 0); + if (!type_name && typed) + complain_at (loc, _("$$ of `%s' has no declared type"), + current_rule->sym->tag); + if (!type_name) + type_name = ""; + obstack_fgrow1 (&obstack_for_string, + "]b4_lhs_value([%s])[", type_name); + current_rule->used = true; + } + else + { + long int num = strtol (cp, NULL, 10); + + if (1 - INT_MAX + rule_length <= num && num <= rule_length) + { + 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_at (loc, _("$%d of `%s' has no declared type"), + n, current_rule->sym->tag); + if (!type_name) + type_name = ""; + obstack_fgrow3 (&obstack_for_string, + "]b4_rhs_value(%d, %d, [%s])[", + rule_length, n, type_name); + symbol_list_n_used_set (current_rule, n, true); + } + else + complain_at (loc, _("integer out of range: %s"), quote (text)); + } + + return true; +} + + +/*----------------------------------------------------------------. +| Map `$?' 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) + { + case BRACED_CODE: + if (handle_action_dollar (text, loc)) + return; + break; + + case PERCENT_DESTRUCTOR: + case PERCENT_INITIAL_ACTION: + case PERCENT_PRINTER: + if (text[1] == '$') + { + obstack_sgrow (&obstack_for_string, "]b4_dollar_dollar["); + return; + } + break; + + default: + break; + } + + complain_at (loc, _("invalid value: %s"), quote (text)); +} + + +/*------------------------------------------------------. +| TEXT is a location token (i.e., a `@...'). Output to | +| OBSTACK_FOR_STRING a reference to this location. | +`------------------------------------------------------*/ + +static inline bool +handle_action_at (char *text, location loc) +{ + char *cp = text + 1; + locations_flag = true; + + if (! current_rule) + return false; + + if (*cp == '$') + obstack_sgrow (&obstack_for_string, "]b4_lhs_location["); + else + { + 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)); + } + + 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) + { + case BRACED_CODE: + handle_action_at (text, loc); + return; + + case PERCENT_INITIAL_ACTION: + case PERCENT_DESTRUCTOR: + case PERCENT_PRINTER: + if (text[1] == '$') + { + obstack_sgrow (&obstack_for_string, "]b4_at_dollar["); + return; + } + break; + + default: + break; + } + + complain_at (loc, _("invalid value: %s"), quote (text)); +} + + +/*------------------------------------------------------. +| Scan NUMBER for a base-BASE integer at location LOC. | +`------------------------------------------------------*/ + +static unsigned long int +scan_integer (char const *number, int base, location loc) +{ + verify (INT_MAX < ULONG_MAX); + unsigned long int num = strtoul (number, NULL, base); + + if (INT_MAX < num) + { + complain_at (loc, _("integer out of range: %s"), quote (number)); + num = INT_MAX; + } + + return num; +} + + +/*------------------------------------------------------------------. +| Convert universal character name UCN to a single-byte character, | +| and return that character. Return -1 if UCN does not correspond | +| to a single-byte character. | +`------------------------------------------------------------------*/ + +static int +convert_ucn_to_byte (char const *ucn) +{ + verify (UCHAR_MAX <= INT_MAX); + unsigned long int code = strtoul (ucn + 2, NULL, 16); + + /* FIXME: Currently we assume Unicode-compatible unibyte characters + on ASCII hosts (i.e., Latin-1 on hosts with 8-bit bytes). On + non-ASCII hosts we support only the portable C character set. + These limitations should be removed once we add support for + multibyte characters. */ + + if (UCHAR_MAX < code) + return -1; + +#if ! ('$' == 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 (&obstack_for_string); +} + + +/*-----------------------------------------------. +| Free all the memory allocated to the scanner. | +`-----------------------------------------------*/ + +void +scanner_free (void) +{ + obstack_free (&obstack_for_string, 0); + /* Reclaim Flex's buffers. */ + yy_delete_buffer (YY_CURRENT_BUFFER); +} |