Flex version 2.5.3 from Vern Paxson at LBL.

1 files changed, 523 insertions, 4 deletions

diff --git a/usr.bin/lex/NEWS b/usr.bin/lex/NEWS
index aff90a3..e4ba93f 100644
--- a/usr.bin/lex/NEWS
+++ b/usr.bin/lex/NEWS
@@ -1,3 +1,525 @@
+Changes between release 2.5.3 (29May96) and release 2.5.2:
+
+	- Some serious bugs in yymore() have been fixed.  In particular,
+	  when using AT&T-lex-compatibility or %array, you can intermix
+	  calls to input(), unput(), and yymore().  (This still doesn't
+	  work for %pointer, and isn't likely to in the future.)
+
+	- A bug in handling NUL's in the input stream of scanners using
+	  REJECT has been fixed.
+
+	- The default main() in libfl.a now repeatedly calls yylex() until
+	  it returns 0, rather than just calling it once.
+
+	- Minor tweak for Windows NT Makefile, MISC/NT/Makefile.
+
+
+Changes between release 2.5.2 (25Apr95) and release 2.5.1:
+
+	- The --prefix configuration option now works.
+
+	- A bug that completely broke the "-Cf" table compression
+	  option has been fixed.
+
+	- A major headache involving "const" declarators and Solaris
+	  systems has been fixed.
+
+	- An octal escape sequence in a flex regular expression must
+	  now contain only the digits 0-7.
+
+	- You can now use "--" on the flex command line to mark the
+	  end of flex options.
+
+	- You can now specify the filename '-' as a synonym for stdin.
+
+	- By default, the scanners generated by flex no longer
+	  statically initialize yyin and yyout to stdin and stdout.
+	  This change is necessary because in some ANSI environments,
+	  stdin and stdout are not compile-time constant.  You can
+	  force the initialization using "%option stdinit" in the first
+	  section of your flex input.
+
+	- "%option nounput" now correctly omits the unput() routine
+	  from the output.
+
+	- "make clean" now removes config.log, config.cache, and the
+	  flex binary.  The fact that it removes the flex binary means
+	  you should take care if making changes to scan.l, to make
+	  sure you don't wind up in a bootstrap problem.
+
+	- In general, the Makefile has been reworked somewhat (thanks
+	  to Francois Pinard) for added flexibility - more changes will
+	  follow in subsequent releases.
+
+	- The .texi and .info files in MISC/texinfo/ have been updated,
+	  thanks also to Francois Pinard.
+
+	- The FlexLexer::yylex(istream* new_in, ostream* new_out) method
+	  now does not have a default for the first argument, to disambiguate
+	  it from FlexLexer::yylex().
+
+	- A bug in destructing a FlexLexer object before doing any scanning
+	  with it has been fixed.
+
+	- A problem with including FlexLexer.h multiple times has been fixed.
+
+	- The alloca() chud necessary to accommodate bison has grown
+	  even uglier, but hopefully more correct.
+
+	- A portability tweak has been added to accommodate compilers that
+	  use char* generic pointers.
+
+	- EBCDIC contact information in the file MISC/EBCDIC has been updated.
+
+	- An OS/2 Makefile and config.h for flex 2.5 is now available in
+	  MISC/OS2/, contributed by Kai Uwe Rommel.
+
+	- The descrip.mms file for building flex under VMS has been updated,
+	  thanks to Pat Rankin.
+
+	- The notes on building flex for the Amiga have been updated for
+	  flex 2.5, contributed by Andreas Scherer.
+
+
+Changes between release 2.5.1 (28Mar95) and release 2.4.7:
+
+	- A new concept of "start condition" scope has been introduced.
+	  A start condition scope is begun with:
+
+		<SCs>{
+
+	  where SCs is a list of one or more start conditions.  Inside
+	  the start condition scope, every rule automatically has the
+	  prefix <SCs> applied to it, until a '}' which matches the
+	  initial '{'.  So, for example:
+
+		<ESC>{
+			"\\n"	return '\n';
+			"\\r"	return '\r';
+			"\\f"	return '\f';
+			"\\0"	return '\0';
+		}
+
+	  is equivalent to:
+
+		<ESC>"\\n"	return '\n';
+		<ESC>"\\r"	return '\r';
+		<ESC>"\\f"	return '\f';
+		<ESC>"\\0"	return '\0';
+
+	  As indicated in this example, rules inside start condition scopes
+	  (and any rule, actually, other than the first) can be indented,
+	  to better show the extent of the scope.
+
+	  Start condition scopes may be nested.
+
+	- The new %option directive can be used in the first section of
+	  a flex scanner to control scanner-generation options.  Most
+	  options are given simply as names, optionally preceded by the
+	  word "no" (with no intervening whitespace) to negate their
+	  meaning.  Some are equivalent to flex flags, so putting them
+	  in your scanner source is equivalent to always specifying
+	  the flag (%option's take precedence over flags):
+
+		7bit	-7 option
+		8bit	-8 option
+		align	-Ca option
+		backup	-b option
+		batch	-B option
+		c++	-+ option
+		caseful	opposite of -i option (caseful is the default);
+		case-sensitive	same as above
+		caseless	-i option;
+		case-insensitive	same as above
+		debug	-d option
+		default	opposite of -s option
+		ecs	-Ce option
+		fast	-F option
+		full	-f option
+		interactive	-I option
+		lex-compat	-l option
+		meta-ecs	-Cm option
+		perf-report	-p option
+		read	-Cr option
+		stdout	-t option
+		verbose	-v option
+		warn	opposite of -w option (so use "%option nowarn" for -w)
+
+		array	equivalent to "%array"
+		pointer	equivalent to "%pointer" (default)
+
+	  Some provide new features:
+
+		always-interactive	generate a scanner which always
+			considers its input "interactive" (no call to isatty()
+			will be made when the scanner runs)
+		main	supply a main program for the scanner, which
+			simply calls yylex().  Implies %option noyywrap.
+		never-interactive	generate a scanner which never
+			considers its input "interactive" (no call to isatty()
+			will be made when the scanner runs)
+		stack	if set, enable start condition stacks (see below)
+		stdinit	if unset ("%option nostdinit"), initialize yyin
+			and yyout statically to nil FILE* pointers, instead
+			of stdin and stdout
+		yylineno	if set, keep track of the current line
+			number in global yylineno (this option is expensive
+			in terms of performance).  The line number is available
+			to C++ scanning objects via the new member function
+			lineno().
+		yywrap	if unset ("%option noyywrap"), scanner does not
+			call yywrap() upon EOF but simply assumes there
+			are no more files to scan
+
+	  Flex scans your rule actions to determine whether you use the
+	  REJECT or yymore features (this is not new).  Two %options can be
+	  used to override its decision, either by setting them to indicate
+	  the feature is indeed used, or unsetting them to indicate it
+	  actually is not used:
+
+		reject
+		yymore
+
+	  Three %option's take string-delimited values, offset with '=':
+
+		outfile="<name>"	equivalent to -o<name>
+		prefix="<name>"		equivalent to -P<name>
+		yyclass="<name>"	set the name of the C++ scanning class
+					(see below)
+
+	  A number of %option's are available for lint purists who
+	  want to suppress the appearance of unneeded routines in
+	  the generated scanner.  Each of the following, if unset,
+	  results in the corresponding routine not appearing in the
+	  generated scanner:
+
+		input, unput
+		yy_push_state, yy_pop_state, yy_top_state
+		yy_scan_buffer, yy_scan_bytes, yy_scan_string
+
+	  You can specify multiple options with a single %option directive,
+	  and multiple directives in the first section of your flex input file.
+
+	- The new function:
+
+		YY_BUFFER_STATE yy_scan_string( const char *str )
+
+	  returns a YY_BUFFER_STATE (which also becomes the current input
+	  buffer) for scanning the given string, which occurs starting
+	  with the next call to yylex().  The string must be NUL-terminated.
+	  A related function:
+
+		YY_BUFFER_STATE yy_scan_bytes( const char *bytes, int len )
+
+	  creates a buffer for scanning "len" bytes (including possibly NUL's)
+	  starting at location "bytes".
+
+	  Note that both of these functions create and scan a *copy* of
+	  the string/bytes.  (This may be desirable, since yylex() modifies
+	  the contents of the buffer it is scanning.)  You can avoid the
+	  copy by using:
+
+		YY_BUFFER_STATE yy_scan_buffer( char *base, yy_size_t size )
+
+	  which scans in place the buffer starting at "base", consisting
+	  of "size" bytes, the last two bytes of which *must* be
+	  YY_END_OF_BUFFER_CHAR (these bytes are not scanned; thus, scanning
+	  consists of base[0] through base[size-2], inclusive).  If you
+	  fail to set up "base" in this manner, yy_scan_buffer returns a
+	  nil pointer instead of creating a new input buffer.
+
+	  The type yy_size_t is an integral type to which you can cast
+	  an integer expression reflecting the size of the buffer.
+
+	- Three new routines are available for manipulating stacks of
+	  start conditions:
+
+		void yy_push_state( int new_state )
+
+	  pushes the current start condition onto the top of the stack
+	  and BEGIN's "new_state" (recall that start condition names are
+	  also integers).
+
+		void yy_pop_state()
+
+	  pops the top of the stack and BEGIN's to it, and
+
+		int yy_top_state()
+
+	  returns the top of the stack without altering the stack's
+	  contents.
+
+	  The start condition stack grows dynamically and so has no built-in
+	  size limitation.  If memory is exhausted, program execution
+	  is aborted.
+
+	  To use start condition stacks, your scanner must include
+	  a "%option stack" directive.
+
+	- flex now supports POSIX character class expressions.  These
+	  are expressions enclosed inside "[:" and ":]" delimiters (which
+	  themselves must appear between the '[' and ']' of a character
+	  class; other elements may occur inside the character class, too).
+	  The expressions flex recognizes are:
+
+		[:alnum:] [:alpha:] [:blank:] [:cntrl:] [:digit:] [:graph:]	
+		[:lower:] [:print:] [:punct:] [:space:] [:upper:] [:xdigit:]
+
+	  These expressions all designate a set of characters equivalent to
+	  the corresponding isXXX function (for example, [:alnum:] designates
+	  those characters for which isalnum() returns true - i.e., any
+	  alphabetic or numeric).  Some systems don't provide isblank(),
+	  so flex defines [:blank:] as a blank or a tab.
+
+	  For example, the following character classes are all equivalent:
+
+		[[:alnum:]]
+		[[:alpha:][:digit:]
+		[[:alpha:]0-9]
+		[a-zA-Z0-9]
+
+	  If your scanner is case-insensitive (-i flag), then [:upper:]
+	  and [:lower:] are equivalent to [:alpha:].
+
+	- The promised rewrite of the C++ FlexLexer class has not yet
+	  been done.  Support for FlexLexer is limited at the moment to
+	  fixing show-stopper bugs, so, for example, the new functions
+	  yy_scan_string() & friends are not available to FlexLexer
+	  objects.
+
+	- The new macro
+
+		yy_set_interactive(is_interactive)
+
+	  can be used to control whether the current buffer is considered
+	  "interactive".  An interactive buffer is processed more slowly,
+	  but must be used when the scanner's input source is indeed
+	  interactive to avoid problems due to waiting to fill buffers
+	  (see the discussion of the -I flag in flex.1).  A non-zero value
+	  in the macro invocation marks the buffer as interactive, a zero
+	  value as non-interactive.  Note that use of this macro overrides
+	  "%option always-interactive" or "%option never-interactive".
+
+	  yy_set_interactive() must be invoked prior to beginning to
+	  scan the buffer.
+
+	- The new macro
+
+		yy_set_bol(at_bol)
+
+	  can be used to control whether the current buffer's scanning
+	  context for the next token match is done as though at the
+	  beginning of a line (non-zero macro argument; makes '^' anchored
+	  rules active) or not at the beginning of a line (zero argument,
+	  '^' rules inactive).
+
+	- Related to this change, the mechanism for determining when a scan is
+	  starting at the beginning of a line has changed.  It used to be
+	  that '^' was active iff the character prior to that at which the
+	  scan started was a newline.  The mechanism now is that '^' is
+	  active iff the last token ended in a newline (or the last call to
+	  input() returned a newline).  For most users, the difference in
+	  mechanisms is negligible.  Where it will make a difference,
+	  however, is if unput() or yyless() is used to alter the input
+	  stream.  When in doubt, use yy_set_bol().
+
+	- The new beginning-of-line mechanism involved changing some fairly
+	  twisted code, so it may have introduced bugs - beware ...
+
+	- The macro YY_AT_BOL() returns true if the next token scanned from
+	  the current buffer will have '^' rules active, false otherwise.
+
+	- The new function
+
+		void yy_flush_buffer( struct yy_buffer_state* b )
+
+	  flushes the contents of the current buffer (i.e., next time
+	  the scanner attempts to match a token using b as the current
+	  buffer, it will begin by invoking YY_INPUT to fill the buffer).
+	  This routine is also available to C++ scanners (unlike some
+	  of the other new routines).
+
+	  The related macro
+
+		YY_FLUSH_BUFFER
+
+	  flushes the contents of the current buffer.
+
+	- A new "-ooutput" option writes the generated scanner to "output".
+	  If used with -t, the scanner is still written to stdout, but
+	  its internal #line directives (see previous item) use "output".
+
+	- Flex now generates #line directives relating the code it
+	  produces to the output file; this means that error messages
+	  in the flex-generated code should be correctly pinpointed.
+
+	- When generating #line directives, filenames with embedded '\'s
+	  have those characters escaped (i.e., turned into '\\').  This
+	  feature helps with reporting filenames for some MS-DOS and OS/2
+	  systems.
+
+	- The FlexLexer class includes two new public member functions:
+
+		virtual void switch_streams( istream* new_in = 0,
+						ostream* new_out = 0 )
+
+	  reassigns yyin to new_in (if non-nil) and yyout to new_out
+	  (ditto), deleting the previous input buffer if yyin is
+	  reassigned.  It is used by:
+
+		int yylex( istream* new_in = 0, ostream* new_out = 0 )
+
+	  which first calls switch_streams() and then returns the value
+	  of calling yylex().
+
+	- C++ scanners now have yy_flex_debug as a member variable of
+	  FlexLexer rather than a global, and member functions for testing
+	  and setting it.
+
+	- When generating a C++ scanning class, you can now use
+
+		%option yyclass="foo"
+
+	  to inform flex that you have derived "foo" as a subclass of
+	  yyFlexLexer, so flex will place your actions in the member
+	  function foo::yylex() instead of yyFlexLexer::yylex().  It also
+	  generates a yyFlexLexer::yylex() member function that generates a
+	  run-time error if called (by invoking yyFlexLexer::LexerError()).
+	  This feature is necessary if your subclass "foo" introduces some
+	  additional member functions or variables that you need to access
+	  from yylex().
+
+	- Current texinfo files in MISC/texinfo, contributed by Francois
+	  Pinard.
+
+	- You can now change the name "flex" to something else (e.g., "lex")
+	  by redefining $(FLEX) in the Makefile.
+
+	- Two bugs (one serious) that could cause "bigcheck" to fail have
+	  been fixed.
+
+	- A number of portability/configuration changes have been made
+	  for easier portability.
+
+	- You can use "YYSTATE" in your scanner as an alias for YY_START
+	  (for AT&T lex compatibility).
+
+	- input() now maintains yylineno.
+
+	- input() no longer trashes yytext.
+
+	- interactive scanners now read characters in YY_INPUT up to a
+	  newline, a large performance gain.
+
+	- C++ scanner objects now work with the -P option.  You include
+	  <FlexLexer.h> once per scanner - see comments in <FlexLexer.h>
+	  (or flex.1) for details.
+
+	- C++ FlexLexer objects now use the "cerr" stream to report -d output
+	  instead of stdio.
+
+	- The -c flag now has its full glorious POSIX interpretation (do
+	  nothing), rather than being interpreted as an old-style -C flag.
+
+	- Scanners generated by flex now include two #define's giving
+	  the major and minor version numbers (YY_FLEX_MAJOR_VERSION,
+	  YY_FLEX_MINOR_VERSION).  These can then be tested to see
+	  whether certain flex features are available.
+
+	- Scanners generated using -l lex compatibility now have the symbol
+	  YY_FLEX_LEX_COMPAT #define'd.
+
+	- When initializing (i.e., yy_init is non-zero on entry to yylex()),
+	  generated scanners now set yy_init to zero before executing
+	  YY_USER_INIT.  This means that you can set yy_init back to a
+	  non-zero value in YY_USER_INIT if you need the scanner to be
+	  reinitialized on the next call.
+
+	- You can now use "#line" directives in the first section of your
+	  scanner specification.
+
+	- When generating full-table scanners (-Cf), flex now puts braces
+	  around each row of the 2-d array initialization, to silence warnings
+	  on over-zealous compilers.
+
+	- Improved support for MS-DOS.  The flex sources have been successfully
+	  built, unmodified, for Borland 4.02 (all that's required is a
+	  Borland Makefile and config.h file, which are supplied in
+	  MISC/Borland - contributed by Terrence O Kane).
+
+	- Improved support for Macintosh using Think C - the sources should
+	  build for this platform "out of the box".  Contributed by Scott
+	  Hofmann.
+
+	- Improved support for VMS, in MISC/VMS/, contributed by Pat Rankin.
+
+	- Support for the Amiga, in MISC/Amiga/, contributed by Andreas
+	  Scherer.  Note that the contributed files were developed for
+	  flex 2.4 and have not been tested with flex 2.5.
+
+	- Some notes on support for the NeXT, in MISC/NeXT, contributed
+	  by Raf Schietekat.
+
+	- The MISC/ directory now includes a preformatted version of flex.1
+	  in flex.man, and pre-yacc'd versions of parse.y in parse.{c,h}.
+
+	- The flex.1 and flexdoc.1 manual pages have been merged.  There
+	  is now just one document, flex.1, which includes an overview
+	  at the beginning to help you find the section you need.
+
+	- Documentation now clarifies that start conditions persist across
+	  switches to new input files or different input buffers.  If you
+	  want to e.g., return to INITIAL, you must explicitly do so.
+
+	- The "Performance Considerations" section of the manual has been
+	  updated.
+
+	- Documented the "yy_act" variable, which when YY_USER_ACTION is
+	  invoked holds the number of the matched rule, and added an
+	  example of using yy_act to profile how often each rule is matched.
+
+	- Added YY_NUM_RULES, a definition that gives the total number
+	  of rules in the file, including the default rule (even if you
+	  use -s).
+
+	- Documentation now clarifies that you can pass a nil FILE* pointer
+	  to yy_create_buffer() or yyrestart() if you've arrange YY_INPUT
+	  to not need yyin.
+
+	- Documentation now clarifies that YY_BUFFER_STATE is a pointer to
+	  an opaque "struct yy_buffer_state".
+
+	- Documentation now stresses that you gain the benefits of removing
+	  backing-up states only if you remove *all* of them.
+
+	- Documentation now points out that traditional lex allows you
+	  to put the action on a separate line from the rule pattern if
+	  the pattern has trailing whitespace (ugh!), but flex doesn't
+	  support this.
+
+	- A broken example in documentation of the difference between
+	  inclusive and exclusive start conditions is now fixed.
+
+	- Usage (-h) report now goes to stdout.
+
+	- Version (-V) info now goes to stdout.
+
+	- More #ifdef chud has been added to the parser in attempt to
+	  deal with bison's use of alloca().
+
+	- "make clean" no longer deletes emacs backup files (*~).
+
+	- Some memory leaks have been fixed.
+
+	- A bug was fixed in which dynamically-expanded buffers were
+	  reallocated a couple of bytes too small.
+
+	- A bug was fixed which could cause flex to read and write beyond
+	  the end of the input buffer.
+
+	- -S will not be going away.
+
+
 Changes between release 2.4.7 (03Aug94) and release 2.4.6:
 
 	- Fixed serious bug in reading multiple files.
@@ -24,7 +546,6 @@ Changes between release 2.4.6 (04Jan94) and release 2.4.5:
 	- The use of 'extern "C++"' in FlexLexer.h has been modified to
 	  get around an incompatibility with g++'s header files.
 
-
 Changes between release 2.4.5 (11Dec93) and release 2.4.4:
 
 	- Fixed bug breaking C++ scanners that use REJECT or variable
@@ -296,9 +817,7 @@ Changes between release 2.4.1 (30Nov93) and release 2.3.8:
 	- The skeleton file is no longer opened at run-time, but instead
 	  compiled into a large string array (thanks to John Gilmore and
 	  friends at Cygnus).  You can still use the -S flag to point flex
-	  at a different skeleton file, though if you use this option let
-	  me know, as I plan to otherwise do away with -S in the near
-	  future.
+	  at a different skeleton file.
 
 	- flex no longer uses a temporary file to store the scanner's
 	  actions.