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authorManoj Srivastava <srivasta@debian.org>2003-12-03 10:38:02 +0000
committerManoj Srivastava <srivasta@debian.org>2003-12-03 10:38:02 +0000
commitedc848712307fe5c881364e12e520e9fe58d9969 (patch)
tree1c055587d094d006b61c425136149350f326f106 /parse.y
Initial import of the 2.5.4a branch
git-archimport-id: srivasta@debian.org--2003-primary/flex--upstream--2.5--base-0
Diffstat (limited to 'parse.y')
-rw-r--r--parse.y913
1 files changed, 913 insertions, 0 deletions
diff --git a/parse.y b/parse.y
new file mode 100644
index 0000000..c6d7eea
--- /dev/null
+++ b/parse.y
@@ -0,0 +1,913 @@
+/* parse.y - parser for flex input */
+
+%token CHAR NUMBER SECTEND SCDECL XSCDECL NAME PREVCCL EOF_OP
+%token OPTION_OP OPT_OUTFILE OPT_PREFIX OPT_YYCLASS
+
+%token CCE_ALNUM CCE_ALPHA CCE_BLANK CCE_CNTRL CCE_DIGIT CCE_GRAPH
+%token CCE_LOWER CCE_PRINT CCE_PUNCT CCE_SPACE CCE_UPPER CCE_XDIGIT
+
+%{
+/*-
+ * Copyright (c) 1990 The Regents of the University of California.
+ * All rights reserved.
+ *
+ * This code is derived from software contributed to Berkeley by
+ * Vern Paxson.
+ *
+ * The United States Government has rights in this work pursuant
+ * to contract no. DE-AC03-76SF00098 between the United States
+ * Department of Energy and the University of California.
+ *
+ * Redistribution and use in source and binary forms with or without
+ * modification are permitted provided that: (1) source distributions retain
+ * this entire copyright notice and comment, and (2) distributions including
+ * binaries display the following acknowledgement: ``This product includes
+ * software developed by the University of California, Berkeley and its
+ * contributors'' in the documentation or other materials provided with the
+ * distribution and in all advertising materials mentioning features or use
+ * of this software. Neither the name of the University nor the names of
+ * its contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
+ */
+
+/* $Header: /home/daffy/u0/vern/flex/RCS/parse.y,v 2.28 95/04/21 11:51:51 vern Exp $ */
+
+
+/* Some versions of bison are broken in that they use alloca() but don't
+ * declare it properly. The following is the patented (just kidding!)
+ * #ifdef chud to fix the problem, courtesy of Francois Pinard.
+ */
+#ifdef YYBISON
+/* AIX requires this to be the first thing in the file. What a piece. */
+# ifdef _AIX
+ #pragma alloca
+# endif
+#endif
+
+#include "flexdef.h"
+
+/* The remainder of the alloca() cruft has to come after including flexdef.h,
+ * so HAVE_ALLOCA_H is (possibly) defined.
+ */
+#ifdef YYBISON
+# ifdef __GNUC__
+# ifndef alloca
+# define alloca __builtin_alloca
+# endif
+# else
+# if HAVE_ALLOCA_H
+# include <alloca.h>
+# else
+# ifdef __hpux
+void *alloca ();
+# else
+# ifdef __TURBOC__
+# include <malloc.h>
+# else
+char *alloca ();
+# endif
+# endif
+# endif
+# endif
+#endif
+
+/* Bletch, ^^^^ that was ugly! */
+
+
+int pat, scnum, eps, headcnt, trailcnt, anyccl, lastchar, i, rulelen;
+int trlcontxt, xcluflg, currccl, cclsorted, varlength, variable_trail_rule;
+
+int *scon_stk;
+int scon_stk_ptr;
+
+static int madeany = false; /* whether we've made the '.' character class */
+int previous_continued_action; /* whether the previous rule's action was '|' */
+
+/* Expand a POSIX character class expression. */
+#define CCL_EXPR(func) \
+ { \
+ int c; \
+ for ( c = 0; c < csize; ++c ) \
+ if ( isascii(c) && func(c) ) \
+ ccladd( currccl, c ); \
+ }
+
+/* While POSIX defines isblank(), it's not ANSI C. */
+#define IS_BLANK(c) ((c) == ' ' || (c) == '\t')
+
+/* On some over-ambitious machines, such as DEC Alpha's, the default
+ * token type is "long" instead of "int"; this leads to problems with
+ * declaring yylval in flexdef.h. But so far, all the yacc's I've seen
+ * wrap their definitions of YYSTYPE with "#ifndef YYSTYPE"'s, so the
+ * following should ensure that the default token type is "int".
+ */
+#define YYSTYPE int
+
+%}
+
+%%
+goal : initlex sect1 sect1end sect2 initforrule
+ { /* add default rule */
+ int def_rule;
+
+ pat = cclinit();
+ cclnegate( pat );
+
+ def_rule = mkstate( -pat );
+
+ /* Remember the number of the default rule so we
+ * don't generate "can't match" warnings for it.
+ */
+ default_rule = num_rules;
+
+ finish_rule( def_rule, false, 0, 0 );
+
+ for ( i = 1; i <= lastsc; ++i )
+ scset[i] = mkbranch( scset[i], def_rule );
+
+ if ( spprdflt )
+ add_action(
+ "YY_FATAL_ERROR( \"flex scanner jammed\" )" );
+ else
+ add_action( "ECHO" );
+
+ add_action( ";\n\tYY_BREAK\n" );
+ }
+ ;
+
+initlex :
+ { /* initialize for processing rules */
+
+ /* Create default DFA start condition. */
+ scinstal( "INITIAL", false );
+ }
+ ;
+
+sect1 : sect1 startconddecl namelist1
+ | sect1 options
+ |
+ | error
+ { synerr( "unknown error processing section 1" ); }
+ ;
+
+sect1end : SECTEND
+ {
+ check_options();
+ scon_stk = allocate_integer_array( lastsc + 1 );
+ scon_stk_ptr = 0;
+ }
+ ;
+
+startconddecl : SCDECL
+ { xcluflg = false; }
+
+ | XSCDECL
+ { xcluflg = true; }
+ ;
+
+namelist1 : namelist1 NAME
+ { scinstal( nmstr, xcluflg ); }
+
+ | NAME
+ { scinstal( nmstr, xcluflg ); }
+
+ | error
+ { synerr( "bad start condition list" ); }
+ ;
+
+options : OPTION_OP optionlist
+ ;
+
+optionlist : optionlist option
+ |
+ ;
+
+option : OPT_OUTFILE '=' NAME
+ {
+ outfilename = copy_string( nmstr );
+ did_outfilename = 1;
+ }
+ | OPT_PREFIX '=' NAME
+ { prefix = copy_string( nmstr ); }
+ | OPT_YYCLASS '=' NAME
+ { yyclass = copy_string( nmstr ); }
+ ;
+
+sect2 : sect2 scon initforrule flexrule '\n'
+ { scon_stk_ptr = $2; }
+ | sect2 scon '{' sect2 '}'
+ { scon_stk_ptr = $2; }
+ |
+ ;
+
+initforrule :
+ {
+ /* Initialize for a parse of one rule. */
+ trlcontxt = variable_trail_rule = varlength = false;
+ trailcnt = headcnt = rulelen = 0;
+ current_state_type = STATE_NORMAL;
+ previous_continued_action = continued_action;
+ in_rule = true;
+
+ new_rule();
+ }
+ ;
+
+flexrule : '^' rule
+ {
+ pat = $2;
+ finish_rule( pat, variable_trail_rule,
+ headcnt, trailcnt );
+
+ if ( scon_stk_ptr > 0 )
+ {
+ for ( i = 1; i <= scon_stk_ptr; ++i )
+ scbol[scon_stk[i]] =
+ mkbranch( scbol[scon_stk[i]],
+ pat );
+ }
+
+ else
+ {
+ /* Add to all non-exclusive start conditions,
+ * including the default (0) start condition.
+ */
+
+ for ( i = 1; i <= lastsc; ++i )
+ if ( ! scxclu[i] )
+ scbol[i] = mkbranch( scbol[i],
+ pat );
+ }
+
+ if ( ! bol_needed )
+ {
+ bol_needed = true;
+
+ if ( performance_report > 1 )
+ pinpoint_message(
+ "'^' operator results in sub-optimal performance" );
+ }
+ }
+
+ | rule
+ {
+ pat = $1;
+ finish_rule( pat, variable_trail_rule,
+ headcnt, trailcnt );
+
+ if ( scon_stk_ptr > 0 )
+ {
+ for ( i = 1; i <= scon_stk_ptr; ++i )
+ scset[scon_stk[i]] =
+ mkbranch( scset[scon_stk[i]],
+ pat );
+ }
+
+ else
+ {
+ for ( i = 1; i <= lastsc; ++i )
+ if ( ! scxclu[i] )
+ scset[i] =
+ mkbranch( scset[i],
+ pat );
+ }
+ }
+
+ | EOF_OP
+ {
+ if ( scon_stk_ptr > 0 )
+ build_eof_action();
+
+ else
+ {
+ /* This EOF applies to all start conditions
+ * which don't already have EOF actions.
+ */
+ for ( i = 1; i <= lastsc; ++i )
+ if ( ! sceof[i] )
+ scon_stk[++scon_stk_ptr] = i;
+
+ if ( scon_stk_ptr == 0 )
+ warn(
+ "all start conditions already have <<EOF>> rules" );
+
+ else
+ build_eof_action();
+ }
+ }
+
+ | error
+ { synerr( "unrecognized rule" ); }
+ ;
+
+scon_stk_ptr :
+ { $$ = scon_stk_ptr; }
+ ;
+
+scon : '<' scon_stk_ptr namelist2 '>'
+ { $$ = $2; }
+
+ | '<' '*' '>'
+ {
+ $$ = scon_stk_ptr;
+
+ for ( i = 1; i <= lastsc; ++i )
+ {
+ int j;
+
+ for ( j = 1; j <= scon_stk_ptr; ++j )
+ if ( scon_stk[j] == i )
+ break;
+
+ if ( j > scon_stk_ptr )
+ scon_stk[++scon_stk_ptr] = i;
+ }
+ }
+
+ |
+ { $$ = scon_stk_ptr; }
+ ;
+
+namelist2 : namelist2 ',' sconname
+
+ | sconname
+
+ | error
+ { synerr( "bad start condition list" ); }
+ ;
+
+sconname : NAME
+ {
+ if ( (scnum = sclookup( nmstr )) == 0 )
+ format_pinpoint_message(
+ "undeclared start condition %s",
+ nmstr );
+ else
+ {
+ for ( i = 1; i <= scon_stk_ptr; ++i )
+ if ( scon_stk[i] == scnum )
+ {
+ format_warn(
+ "<%s> specified twice",
+ scname[scnum] );
+ break;
+ }
+
+ if ( i > scon_stk_ptr )
+ scon_stk[++scon_stk_ptr] = scnum;
+ }
+ }
+ ;
+
+rule : re2 re
+ {
+ if ( transchar[lastst[$2]] != SYM_EPSILON )
+ /* Provide final transition \now/ so it
+ * will be marked as a trailing context
+ * state.
+ */
+ $2 = link_machines( $2,
+ mkstate( SYM_EPSILON ) );
+
+ mark_beginning_as_normal( $2 );
+ current_state_type = STATE_NORMAL;
+
+ if ( previous_continued_action )
+ {
+ /* We need to treat this as variable trailing
+ * context so that the backup does not happen
+ * in the action but before the action switch
+ * statement. If the backup happens in the
+ * action, then the rules "falling into" this
+ * one's action will *also* do the backup,
+ * erroneously.
+ */
+ if ( ! varlength || headcnt != 0 )
+ warn(
+ "trailing context made variable due to preceding '|' action" );
+
+ /* Mark as variable. */
+ varlength = true;
+ headcnt = 0;
+ }
+
+ if ( lex_compat || (varlength && headcnt == 0) )
+ { /* variable trailing context rule */
+ /* Mark the first part of the rule as the
+ * accepting "head" part of a trailing
+ * context rule.
+ *
+ * By the way, we didn't do this at the
+ * beginning of this production because back
+ * then current_state_type was set up for a
+ * trail rule, and add_accept() can create
+ * a new state ...
+ */
+ add_accept( $1,
+ num_rules | YY_TRAILING_HEAD_MASK );
+ variable_trail_rule = true;
+ }
+
+ else
+ trailcnt = rulelen;
+
+ $$ = link_machines( $1, $2 );
+ }
+
+ | re2 re '$'
+ { synerr( "trailing context used twice" ); }
+
+ | re '$'
+ {
+ headcnt = 0;
+ trailcnt = 1;
+ rulelen = 1;
+ varlength = false;
+
+ current_state_type = STATE_TRAILING_CONTEXT;
+
+ if ( trlcontxt )
+ {
+ synerr( "trailing context used twice" );
+ $$ = mkstate( SYM_EPSILON );
+ }
+
+ else if ( previous_continued_action )
+ {
+ /* See the comment in the rule for "re2 re"
+ * above.
+ */
+ warn(
+ "trailing context made variable due to preceding '|' action" );
+
+ varlength = true;
+ }
+
+ if ( lex_compat || varlength )
+ {
+ /* Again, see the comment in the rule for
+ * "re2 re" above.
+ */
+ add_accept( $1,
+ num_rules | YY_TRAILING_HEAD_MASK );
+ variable_trail_rule = true;
+ }
+
+ trlcontxt = true;
+
+ eps = mkstate( SYM_EPSILON );
+ $$ = link_machines( $1,
+ link_machines( eps, mkstate( '\n' ) ) );
+ }
+
+ | re
+ {
+ $$ = $1;
+
+ if ( trlcontxt )
+ {
+ if ( lex_compat || (varlength && headcnt == 0) )
+ /* Both head and trail are
+ * variable-length.
+ */
+ variable_trail_rule = true;
+ else
+ trailcnt = rulelen;
+ }
+ }
+ ;
+
+
+re : re '|' series
+ {
+ varlength = true;
+ $$ = mkor( $1, $3 );
+ }
+
+ | series
+ { $$ = $1; }
+ ;
+
+
+re2 : re '/'
+ {
+ /* This rule is written separately so the
+ * reduction will occur before the trailing
+ * series is parsed.
+ */
+
+ if ( trlcontxt )
+ synerr( "trailing context used twice" );
+ else
+ trlcontxt = true;
+
+ if ( varlength )
+ /* We hope the trailing context is
+ * fixed-length.
+ */
+ varlength = false;
+ else
+ headcnt = rulelen;
+
+ rulelen = 0;
+
+ current_state_type = STATE_TRAILING_CONTEXT;
+ $$ = $1;
+ }
+ ;
+
+series : series singleton
+ {
+ /* This is where concatenation of adjacent patterns
+ * gets done.
+ */
+ $$ = link_machines( $1, $2 );
+ }
+
+ | singleton
+ { $$ = $1; }
+ ;
+
+singleton : singleton '*'
+ {
+ varlength = true;
+
+ $$ = mkclos( $1 );
+ }
+
+ | singleton '+'
+ {
+ varlength = true;
+ $$ = mkposcl( $1 );
+ }
+
+ | singleton '?'
+ {
+ varlength = true;
+ $$ = mkopt( $1 );
+ }
+
+ | singleton '{' NUMBER ',' NUMBER '}'
+ {
+ varlength = true;
+
+ if ( $3 > $5 || $3 < 0 )
+ {
+ synerr( "bad iteration values" );
+ $$ = $1;
+ }
+ else
+ {
+ if ( $3 == 0 )
+ {
+ if ( $5 <= 0 )
+ {
+ synerr(
+ "bad iteration values" );
+ $$ = $1;
+ }
+ else
+ $$ = mkopt(
+ mkrep( $1, 1, $5 ) );
+ }
+ else
+ $$ = mkrep( $1, $3, $5 );
+ }
+ }
+
+ | singleton '{' NUMBER ',' '}'
+ {
+ varlength = true;
+
+ if ( $3 <= 0 )
+ {
+ synerr( "iteration value must be positive" );
+ $$ = $1;
+ }
+
+ else
+ $$ = mkrep( $1, $3, INFINITY );
+ }
+
+ | singleton '{' NUMBER '}'
+ {
+ /* The singleton could be something like "(foo)",
+ * in which case we have no idea what its length
+ * is, so we punt here.
+ */
+ varlength = true;
+
+ if ( $3 <= 0 )
+ {
+ synerr( "iteration value must be positive" );
+ $$ = $1;
+ }
+
+ else
+ $$ = link_machines( $1,
+ copysingl( $1, $3 - 1 ) );
+ }
+
+ | '.'
+ {
+ if ( ! madeany )
+ {
+ /* Create the '.' character class. */
+ anyccl = cclinit();
+ ccladd( anyccl, '\n' );
+ cclnegate( anyccl );
+
+ if ( useecs )
+ mkeccl( ccltbl + cclmap[anyccl],
+ ccllen[anyccl], nextecm,
+ ecgroup, csize, csize );
+
+ madeany = true;
+ }
+
+ ++rulelen;
+
+ $$ = mkstate( -anyccl );
+ }
+
+ | fullccl
+ {
+ if ( ! cclsorted )
+ /* Sort characters for fast searching. We
+ * use a shell sort since this list could
+ * be large.
+ */
+ cshell( ccltbl + cclmap[$1], ccllen[$1], true );
+
+ if ( useecs )
+ mkeccl( ccltbl + cclmap[$1], ccllen[$1],
+ nextecm, ecgroup, csize, csize );
+
+ ++rulelen;
+
+ $$ = mkstate( -$1 );
+ }
+
+ | PREVCCL
+ {
+ ++rulelen;
+
+ $$ = mkstate( -$1 );
+ }
+
+ | '"' string '"'
+ { $$ = $2; }
+
+ | '(' re ')'
+ { $$ = $2; }
+
+ | CHAR
+ {
+ ++rulelen;
+
+ if ( caseins && $1 >= 'A' && $1 <= 'Z' )
+ $1 = clower( $1 );
+
+ $$ = mkstate( $1 );
+ }
+ ;
+
+fullccl : '[' ccl ']'
+ { $$ = $2; }
+
+ | '[' '^' ccl ']'
+ {
+ cclnegate( $3 );
+ $$ = $3;
+ }
+ ;
+
+ccl : ccl CHAR '-' CHAR
+ {
+ if ( caseins )
+ {
+ if ( $2 >= 'A' && $2 <= 'Z' )
+ $2 = clower( $2 );
+ if ( $4 >= 'A' && $4 <= 'Z' )
+ $4 = clower( $4 );
+ }
+
+ if ( $2 > $4 )
+ synerr( "negative range in character class" );
+
+ else
+ {
+ for ( i = $2; i <= $4; ++i )
+ ccladd( $1, i );
+
+ /* Keep track if this ccl is staying in
+ * alphabetical order.
+ */
+ cclsorted = cclsorted && ($2 > lastchar);
+ lastchar = $4;
+ }
+
+ $$ = $1;
+ }
+
+ | ccl CHAR
+ {
+ if ( caseins && $2 >= 'A' && $2 <= 'Z' )
+ $2 = clower( $2 );
+
+ ccladd( $1, $2 );
+ cclsorted = cclsorted && ($2 > lastchar);
+ lastchar = $2;
+ $$ = $1;
+ }
+
+ | ccl ccl_expr
+ {
+ /* Too hard to properly maintain cclsorted. */
+ cclsorted = false;
+ $$ = $1;
+ }
+
+ |
+ {
+ cclsorted = true;
+ lastchar = 0;
+ currccl = $$ = cclinit();
+ }
+ ;
+
+ccl_expr: CCE_ALNUM { CCL_EXPR(isalnum) }
+ | CCE_ALPHA { CCL_EXPR(isalpha) }
+ | CCE_BLANK { CCL_EXPR(IS_BLANK) }
+ | CCE_CNTRL { CCL_EXPR(iscntrl) }
+ | CCE_DIGIT { CCL_EXPR(isdigit) }
+ | CCE_GRAPH { CCL_EXPR(isgraph) }
+ | CCE_LOWER { CCL_EXPR(islower) }
+ | CCE_PRINT { CCL_EXPR(isprint) }
+ | CCE_PUNCT { CCL_EXPR(ispunct) }
+ | CCE_SPACE { CCL_EXPR(isspace) }
+ | CCE_UPPER {
+ if ( caseins )
+ CCL_EXPR(islower)
+ else
+ CCL_EXPR(isupper)
+ }
+ | CCE_XDIGIT { CCL_EXPR(isxdigit) }
+ ;
+
+string : string CHAR
+ {
+ if ( caseins && $2 >= 'A' && $2 <= 'Z' )
+ $2 = clower( $2 );
+
+ ++rulelen;
+
+ $$ = link_machines( $1, mkstate( $2 ) );
+ }
+
+ |
+ { $$ = mkstate( SYM_EPSILON ); }
+ ;
+
+%%
+
+
+/* build_eof_action - build the "<<EOF>>" action for the active start
+ * conditions
+ */
+
+void build_eof_action()
+ {
+ register int i;
+ char action_text[MAXLINE];
+
+ for ( i = 1; i <= scon_stk_ptr; ++i )
+ {
+ if ( sceof[scon_stk[i]] )
+ format_pinpoint_message(
+ "multiple <<EOF>> rules for start condition %s",
+ scname[scon_stk[i]] );
+
+ else
+ {
+ sceof[scon_stk[i]] = true;
+ sprintf( action_text, "case YY_STATE_EOF(%s):\n",
+ scname[scon_stk[i]] );
+ add_action( action_text );
+ }
+ }
+
+ line_directive_out( (FILE *) 0, 1 );
+
+ /* This isn't a normal rule after all - don't count it as
+ * such, so we don't have any holes in the rule numbering
+ * (which make generating "rule can never match" warnings
+ * more difficult.
+ */
+ --num_rules;
+ ++num_eof_rules;
+ }
+
+
+/* format_synerr - write out formatted syntax error */
+
+void format_synerr( msg, arg )
+char msg[], arg[];
+ {
+ char errmsg[MAXLINE];
+
+ (void) sprintf( errmsg, msg, arg );
+ synerr( errmsg );
+ }
+
+
+/* synerr - report a syntax error */
+
+void synerr( str )
+char str[];
+ {
+ syntaxerror = true;
+ pinpoint_message( str );
+ }
+
+
+/* format_warn - write out formatted warning */
+
+void format_warn( msg, arg )
+char msg[], arg[];
+ {
+ char warn_msg[MAXLINE];
+
+ (void) sprintf( warn_msg, msg, arg );
+ warn( warn_msg );
+ }
+
+
+/* warn - report a warning, unless -w was given */
+
+void warn( str )
+char str[];
+ {
+ line_warning( str, linenum );
+ }
+
+/* format_pinpoint_message - write out a message formatted with one string,
+ * pinpointing its location
+ */
+
+void format_pinpoint_message( msg, arg )
+char msg[], arg[];
+ {
+ char errmsg[MAXLINE];
+
+ (void) sprintf( errmsg, msg, arg );
+ pinpoint_message( errmsg );
+ }
+
+
+/* pinpoint_message - write out a message, pinpointing its location */
+
+void pinpoint_message( str )
+char str[];
+ {
+ line_pinpoint( str, linenum );
+ }
+
+
+/* line_warning - report a warning at a given line, unless -w was given */
+
+void line_warning( str, line )
+char str[];
+int line;
+ {
+ char warning[MAXLINE];
+
+ if ( ! nowarn )
+ {
+ sprintf( warning, "warning, %s", str );
+ line_pinpoint( warning, line );
+ }
+ }
+
+
+/* line_pinpoint - write out a message, pinpointing it at the given line */
+
+void line_pinpoint( str, line )
+char str[];
+int line;
+ {
+ fprintf( stderr, "\"%s\", line %d: %s\n", infilename, line, str );
+ }
+
+
+/* yyerror - eat up an error message from the parser;
+ * currently, messages are ignore
+ */
+
+void yyerror( msg )
+char msg[];
+ {
+ }