Implement and document %option yylmax to replace #define YYLMAX.

Test in tests/test-yylmax.

doc/flex.texi

@@ -1137,16 +1137,16 @@ for @code{%array}.
 
 The @code{%array} declaration defines @code{yytext} to be an array of
 @code{YYLMAX} characters, which defaults to a fairly large value.  You
-can change the size by simply #define'ing @code{YYLMAX} to a different
-value in the first section of your @code{flex} input.  As mentioned
-above, with @code{%pointer} yytext grows dynamically to accommodate
-large tokens.  While this means your @code{%pointer} scanner can
-accommodate very large tokens (such as matching entire blocks of
-comments), bear in mind that each time the scanner must resize
-@code{yytext} it also must rescan the entire token from the beginning,
-so matching such tokens can prove slow.  @code{yytext} presently does
-@emph{not} dynamically grow if a call to @code{unput()} results in too
-much text being pushed back; instead, a run-time error results.
+can change the size to a different value with @code{%option yylmax
+= NNN}.  As mentioned above, with @code{%pointer} yytext grows
+dynamically to accommodate large tokens.  While this means your
+@code{%pointer} scanner can accommodate very large tokens (such as
+matching entire blocks of comments), bear in mind that each time the
+scanner must resize @code{yytext} it also must rescan the entire token
+from the beginning, so matching such tokens can prove slow.
+@code{yytext} presently does @emph{not} dynamically grow if a call to
+@code{unput()} results in too much text being pushed back; instead, a
+run-time error results.
 
 @cindex %array, with C++
 Also note that you cannot use @code{%array} with C++ scanner classes
@@ -2398,11 +2398,11 @@ lengthened (you cannot append characters to the end).
 
 @cindex yytext, default array size
 @cindex array, default size for yytext
-@vindex YYLMAX
+@vindex yylmax
 If the special directive @code{%array} appears in the first section of
 the scanner description, then @code{yytext} is instead declared
-@code{char yytext[YYLMAX]}, where @code{YYLMAX} is a macro definition
-that you can redefine in the first section if you don't like the default
+to be an array of YYLMAX characters, where @code{YYLMAX} is a parameter
+that you can redefine with a @code{%yylmax} option if you don't like the default
 value (generally 8KB).  Using @code{%array} results in somewhat slower
 scanners, but the value of @code{yytext} becomes immune to calls to
 @code{unput()}, which potentially destroy its value when @code{yytext} is
@@ -5292,9 +5292,8 @@ its rules.  This error can also occur due to internal problems.
 @item
 @samp{token too large, exceeds YYLMAX}. your scanner uses @code{%array}
 and one of its rules matched a string longer than the @code{YYLMAX}
-constant (8K bytes by default).  You can increase the value by
-#define'ing @code{YYLMAX} in the definitions section of your @code{flex}
-input.
+constant (8K bytes by default).  You can increase the value with the
+@code{%yylmax} option.
 
 @item
 @samp{scanner requires -8 flag to use the character 'x'}. Your scanner
@@ -8721,10 +8720,13 @@ BEGIN: Replaced by yybegin()
 ECHO: Replaced by yyecho()
 
 @item
-REJECT: Replaced by yyreject()
+#define REJECT: Replaced by yyreject()
 
 @item
-YY_DECL: Replaced by the %yydecl directive.
+#define YY_DECL: Replaced by the %yydecl directive.
+
+@item
+#define YYLMAX: Replaced by the %yylmax option.
 @end itemize
 
 @node Indices,  , Appendices, Top

src/cpp-flex.skl

@@ -89,7 +89,10 @@ m4_define([[M4_HOOK_EOF_STATE_CASE_TERMINATE]], [[		yyterminate();
 m4_define([[M4_HOOK_CONST_DEFINE]], [[#define $1 $2
 ]])
 
-m4_define([[M4_HOOK_SET_YY_DECL]], [[#define YY_DECL $1]])
+m4_define([[M4_HOOK_SET_YY_DECL]], [[#define YY_DECL $1
+]])
+m4_define([[M4_HOOK_SET_YYLMAX]], [[#define YYLMAX $1
+]])
 
 %% [0.0] Make hook macros available to Flex
 

src/flexdef.h

@@ -352,6 +352,7 @@ struct ctrl_bundle_t {
        				// otherwise, use fread(). 
 	char *yyclass;		// yyFlexLexer subclass to use for YY_DECL
 	char *yydecl;		// user-specfied prototype for yylex.
+	int yylmax;		// Maximum buffer length if %array
 	bool yytext_is_array;	// if true (i.e., %array directive), then declare
 				// yytext as array instead of a character pointer.
 				// Nice and inefficient.
@@ -669,6 +670,7 @@ extern unsigned char *ccltbl;
 
 /* Variables for miscellaneous information:
  * nmstr - last NAME scanned by the scanner
+ * nmval - last numeric scanned by the scanner
  * sectnum - section number currently being parsed
  * nummt - number of empty nxt/chk table entries
  * hshcol - number of hash collisions detected by snstods
@@ -688,7 +690,7 @@ extern unsigned char *ccltbl;
  */
 
 extern char nmstr[MAXLINE];
-extern int sectnum, nummt, hshcol, dfaeql, numeps, eps2, num_reallocs;
+extern int sectnum, nummt, hshcol, dfaeql, numeps, eps2, num_reallocs, nmval;
 extern int tmpuses, totnst, peakpairs, numuniq, numdup, hshsave;
 extern int num_backing_up, bol_needed;
 

src/main.c

@@ -86,7 +86,7 @@ int     lastccl, *cclmap, *ccllen, *cclng, cclreuse;
 int     current_maxccls, current_max_ccl_tbl_size;
 unsigned char   *ccltbl;
 char    nmstr[MAXLINE];
-int     sectnum, nummt, hshcol, dfaeql, numeps, eps2, num_reallocs;
+int     sectnum, nummt, hshcol, dfaeql, numeps, eps2, num_reallocs, nmval;
 int     tmpuses, totnst, peakpairs, numuniq, numdup, hshsave;
 int     num_backing_up, bol_needed;
 int     end_of_buffer_state;
@@ -1288,6 +1288,10 @@ void readin (void)
 		out_str ("M4_HOOK_SET_YY_DECL(%s)\n", cp);
 	}
 
+	if (ctrl.yylmax != 0) {
+		out_dec ("M4_HOOK_SET_YYLMAX(%d)\n", ctrl.yylmax);
+	}
+	
 	/* Dump the user defined preproc directives. */
 	if (userdef_buf.elts)
 		outn ((char *) (userdef_buf.elts));

src/parse.y

@@ -2,7 +2,7 @@
 
 %token CHAR NUMBER SECTEND SCDECL XSCDECL NAME PREVCCL EOF_OP
 %token TOK_OPTION TOK_OUTFILE TOK_PREFIX TOK_YYCLASS TOK_HEADER_FILE TOK_EXTRA_TYPE
-%token TOK_TABLES_FILE
+%token TOK_TABLES_FILE TOK_YYLMAX TOK_NUMERIC
 
 %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
@@ -206,6 +206,8 @@ option		:  TOK_OUTFILE '=' NAME
 			{ ctrl.yyclass = xstrdup(nmstr); }
 		|  TOK_HEADER_FILE '=' NAME
 			{ env.headerfilename = xstrdup(nmstr); }
+		|  TOK_YYLMAX '=' TOK_NUMERIC
+		{ ctrl.yylmax = nmval; }
 	    |  TOK_TABLES_FILE '=' NAME
             { tablesext = true; tablesfilename = xstrdup(nmstr); }
 		;

src/scan.l

@@ -351,6 +351,7 @@ M4QEND      "]""]"
 	{WS}		option_sense = true;
 
 	"="		return '=';
+	[[:digit:]]+	{nmval = atoi(yytext); return TOK_NUMERIC;}
 
 	no		option_sense = ! option_sense;
 
@@ -450,6 +451,7 @@ M4QEND      "]""]"
 	outfile		return TOK_OUTFILE;
 	prefix		return TOK_PREFIX;
 	yyclass		return TOK_YYCLASS;
+	yylmax		return TOK_YYLMAX;
 	header(-file)?      return TOK_HEADER_FILE;
 	tables-file         return TOK_TABLES_FILE;
 	tables-verify   {

tests/test-yylmax

@@ -0,0 +1,14 @@
+#! /bin/sh
+# Test %yylmax option of flex in any cpp-based back end
+
+trap 'rm /tmp/td$$' EXIT HUP INT QUIT TERM 
+cat >/tmp/td$$ <<EOF
+%option yylmax=333
+%%
+%%
+EOF
+
+( ../src/flex -t /tmp/td$$  | grep "#define YYLMAX 333" >/dev/null ) || (echo "%yylmax test failed." >&2; exit 1)
+
+
+