Enable SQL engine without flex and Bison installed

Flex and Bison are only really needed by package maintainers to generate
new C files. So check in the generated files, enable SQL by default, and
allow disabling with --disable-sql.

.gitignore

@@ -25,9 +25,6 @@ libmdbsql.pc
 libtool
 src/extras/mdb-hexdump
 src/odbc/unittest
-src/sql/lexer.c
-src/sql/parser.c
-src/sql/parser.h
 src/util/mdb-array
 src/util/mdb-count
 src/util/mdb-export

README.md

@@ -67,11 +67,6 @@ First, you must have reasonably current installations of:
 * [automake](https://www.gnu.org/software/automake/)
 * [autoconf](https://www.gnu.org/software/autoconf/) (version >= 2.58)
 
-If you want to build the SQL engine, you'll need
-[bison](https://www.gnu.org/software/bison/) (version >= 3.0) or
-[byacc](https://invisible-island.net/byacc/byacc.html), and
-[flex](https://github.com/westes/flex).
-
 If you want to build the ODBC driver, you'll need `unixodbc-dev` (version
 2.2.10 or above) or [iodbc](http://www.iodbc.org/dataspace/doc/iodbc/wiki/iodbcWiki/WelcomeVisitors).
 
@@ -123,7 +118,7 @@ enivornment variables. Or, you can disable GLib entirely with the
 `--disable-glib` flag, in which case MDB Tools will use an internal
 implementation of GLib's functions.
 
-configure can be passed any of the following flags to turn on other 
+configure can be passed any of the following flags to turn on or off other
 capabilities.  Note that the options `--with-unixodbc` and `--with-iodbc` are
 mutually exclusive.
 
@@ -132,6 +127,7 @@ mutually exclusive.
                  causes the unixODBC driver to be built.
 --with-iodbc     specifies the location of the iODBC driver manager and 
                  causes the iODBC driver to be built.
+--disable-sql    do not build the SQL engine
 ```
 
 A list of general options is available in the [INSTALL](./INSTALL) file, and

configure.ac

@@ -56,16 +56,15 @@ dnl ---------------------------------------------------------------------
 dnl Compile time options
 dnl ---------------------------------------------------------------------
 
-sql=true
-AC_MSG_CHECKING( Are we using flex )
+AC_MSG_CHECKING( for flex )
 if test "x$LEX" = "xflex"; then
 LFLAGS="$LFLAGS -i -8"
 AC_MSG_RESULT( yes );
 else
-AC_MSG_RESULT( no - SQL engine disable);
-sql=false
+AC_MSG_RESULT( no );
 fi
 
+AC_MSG_CHECKING( for bison 3.0+ )
 if $YACC -V | grep "bison.* 3[.]" >/dev/null 2>&1; then
     if $YACC -Wno-conflicts-sr -V >/dev/null 2>&1; then
         YFLAGS="$YFLAGS -Wno-conflicts-sr"
@@ -73,18 +72,19 @@ if $YACC -V | grep "bison.* 3[.]" >/dev/null 2>&1; then
     if $YACC -Wno-yacc -V >/dev/null 2>&1; then
         YFLAGS="$YFLAGS -Wno-yacc"
     fi
+    AC_MSG_RESULT( yes );
 else
-    AC_MSG_WARN([Bison 3.0+ is not available: SQL disabled.])
-    sql=false
+    AC_MSG_RESULT( no );
 fi
 
-if test "x$sql" = "xtrue"; then
-	CFLAGS="$CFLAGS -DSQL"
-	OPTDIRS="$OPTDIRS sql"
+AC_ARG_ENABLE(sql,
+  AS_HELP_STRING([--disable-sql], [disable SQL support]),
+  enable_sql="$enableval", [enable_sql=yes])
+if test "$enable_sql" = yes; then
+  OPTDIRS="$OPTDIRS sql"
 fi
+AM_CONDITIONAL(ENABLE_SQL, test "$enable_sql" = yes)
 
-AM_CONDITIONAL(SQL, test x$sql = xtrue)
-AC_SUBST(SQL)
 AC_SUBST(LFLAGS)
 
 CFLAGS="$CFLAGS -Wall -Werror"
@@ -182,8 +182,8 @@ if test "$with_unixodbc"; then
 fi
 
 if test "x$HAVE_ODBC" = "xtrue"; then
-	if test "x$sql" != "xtrue" ; then
-		AC_MSG_ERROR([ODBC requires flex and bison for the SQL engine])
+	if test "x$enable_sql" != "xtrue" ; then
+		AC_MSG_ERROR([ODBC requires the SQL engine to be enabled])
 	fi
 
 	AC_SUBST(ODBC_CFLAGS)
@@ -290,7 +290,7 @@ reset=$(tput sgr0 2>/dev/null)
 AC_MSG_NOTICE([])
 AC_MSG_NOTICE([${bold}MDB Tools $VERSION - Configuration summary${reset}])
 AC_MSG_NOTICE([])
-if test x$sql = xtrue; then summary=${bold_green}enabled; else summary=${bold_red}disabled; fi
+if test x$enable_sql = xyes; then summary=${bold_green}enabled; else summary=${bold_red}disabled; fi
 AC_MSG_NOTICE([   SQL             : ${summary}${reset}])
 if test x$HAVE_ODBC = xtrue; then summary=${bold_green}enabled; else summary=${bold_red}disabled; fi
 AC_MSG_NOTICE([   ODBC            : ${summary}${reset}])

doc/Makefile.am

@@ -4,9 +4,12 @@ PRODUCT = MDBTools
 
 dist_man_MANS =
 if ENABLE_MAN
-  dist_man_MANS += mdb-tables.1 mdb-ver.1 mdb-export.1 mdb-schema.1 mdb-sql.1 \
+  dist_man_MANS += mdb-tables.1 mdb-ver.1 mdb-export.1 mdb-schema.1 \
 	mdb-array.1 mdb-header.1 mdb-hexdump.1 mdb-parsecsv.1 mdb-prop.1 mdb-import.1 \
 	mdb-count.1 mdb-json.1 mdb-queries.1
+if ENABLE_SQL
+  dist_man_MANS += mdb-sql.1
+endif
 endif
 CLEANFILES = ${dist_man_MANS}
 EXTRA_DIST	= mdb-tables.txt mdb-ver.txt mdb-export.txt mdb-schema.txt mdb-sql.txt \

src/sql/Makefile.am

@@ -1,10 +1,9 @@
 AUTOMAKE_OPTIONS = subdir-objects
 BUILT_SOURCES = parser.h
-AM_YFLAGS = -d -o parser.c
+AM_YFLAGS = -d
 lib_LTLIBRARIES	=	libmdbsql.la
 libmdbsql_la_SOURCES=	mdbsql.c parser.y lexer.l 
 libmdbsql_la_LDFLAGS = -version-info $(VERSION_INFO) -export-symbols-regex '^mdb_sql_'
-CLEANFILES = parser.c parser.h lexer.c
 AM_CFLAGS	=	-I$(top_srcdir)/include $(GLIB_CFLAGS)
 LIBS	=	$(GLIB_LIBS)
 libmdbsql_la_LIBADD =	../libmdb/libmdb.la

src/sql/parser.h

@@ -0,0 +1,128 @@
+/* A Bison parser, made by GNU Bison 3.7.1.  */
+
+/* Bison interface for Yacc-like parsers in C
+
+   Copyright (C) 1984, 1989-1990, 2000-2015, 2018-2020 Free Software Foundation,
+   Inc.
+
+   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 3 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, see <http://www.gnu.org/licenses/>.  */
+
+/* As a special exception, you may create a larger work that contains
+   part or all of the Bison parser skeleton and distribute that work
+   under terms of your choice, so long as that work isn't itself a
+   parser generator using the skeleton or a modified version thereof
+   as a parser skeleton.  Alternatively, if you modify or redistribute
+   the parser skeleton itself, you may (at your option) remove this
+   special exception, which will cause the skeleton and the resulting
+   Bison output files to be licensed under the GNU General Public
+   License without this special exception.
+
+   This special exception was added by the Free Software Foundation in
+   version 2.2 of Bison.  */
+
+/* DO NOT RELY ON FEATURES THAT ARE NOT DOCUMENTED in the manual,
+   especially those whose name start with YY_ or yy_.  They are
+   private implementation details that can be changed or removed.  */
+
+#ifndef YY_YY_PARSER_H_INCLUDED
+# define YY_YY_PARSER_H_INCLUDED
+/* Debug traces.  */
+#ifndef YYDEBUG
+# define YYDEBUG 0
+#endif
+#if YYDEBUG
+extern int yydebug;
+#endif
+
+/* Token kinds.  */
+#ifndef YYTOKENTYPE
+# define YYTOKENTYPE
+  enum yytokentype
+  {
+    YYEMPTY = -2,
+    YYEOF = 0,                     /* "end of file"  */
+    YYerror = 256,                 /* error  */
+    YYUNDEF = 257,                 /* "invalid token"  */
+    IDENT = 258,                   /* IDENT  */
+    NAME = 259,                    /* NAME  */
+    PATH = 260,                    /* PATH  */
+    STRING = 261,                  /* STRING  */
+    NUMBER = 262,                  /* NUMBER  */
+    SELECT = 263,                  /* SELECT  */
+    FROM = 264,                    /* FROM  */
+    WHERE = 265,                   /* WHERE  */
+    CONNECT = 266,                 /* CONNECT  */
+    DISCONNECT = 267,              /* DISCONNECT  */
+    TO = 268,                      /* TO  */
+    LIST = 269,                    /* LIST  */
+    TABLES = 270,                  /* TABLES  */
+    AND = 271,                     /* AND  */
+    OR = 272,                      /* OR  */
+    NOT = 273,                     /* NOT  */
+    LIMIT = 274,                   /* LIMIT  */
+    COUNT = 275,                   /* COUNT  */
+    STRPTIME = 276,                /* STRPTIME  */
+    DESCRIBE = 277,                /* DESCRIBE  */
+    TABLE = 278,                   /* TABLE  */
+    TOP = 279,                     /* TOP  */
+    PERCENT = 280,                 /* PERCENT  */
+    LTEQ = 281,                    /* LTEQ  */
+    GTEQ = 282,                    /* GTEQ  */
+    LIKE = 283,                    /* LIKE  */
+    IS = 284,                      /* IS  */
+    NUL = 285,                     /* NUL  */
+    EQ = 286,                      /* EQ  */
+    LT = 287,                      /* LT  */
+    GT = 288                       /* GT  */
+  };
+  typedef enum yytokentype yytoken_kind_t;
+#endif
+
+/* Value type.  */
+#if ! defined YYSTYPE && ! defined YYSTYPE_IS_DECLARED
+union YYSTYPE
+{
+#line 55 "parser.y"
+
+	char *name;
+	double dval;
+	int ival;
+
+#line 103 "parser.h"
+
+};
+typedef union YYSTYPE YYSTYPE;
+# define YYSTYPE_IS_TRIVIAL 1
+# define YYSTYPE_IS_DECLARED 1
+#endif
+
+/* Location type.  */
+#if ! defined YYLTYPE && ! defined YYLTYPE_IS_DECLARED
+typedef struct YYLTYPE YYLTYPE;
+struct YYLTYPE
+{
+  int first_line;
+  int first_column;
+  int last_line;
+  int last_column;
+};
+# define YYLTYPE_IS_DECLARED 1
+# define YYLTYPE_IS_TRIVIAL 1
+#endif
+
+
+
+int yyparse (struct sql_context* parser_ctx);
+
+#endif /* !YY_YY_PARSER_H_INCLUDED  */

src/util/Makefile.am

@@ -1,12 +1,13 @@
 AUTOMAKE_OPTIONS = subdir-objects
 SUBDIRS = bash-completion
-bin_PROGRAMS	=	mdb-export mdb-array mdb-schema mdb-tables mdb-parsecsv mdb-header mdb-sql mdb-ver mdb-prop mdb-count mdb-queries mdb-json
+bin_PROGRAMS	=	mdb-export mdb-array mdb-schema mdb-tables mdb-parsecsv mdb-header mdb-ver mdb-prop mdb-count mdb-queries mdb-json
 noinst_PROGRAMS = mdb-import prtable prcat prdata prkkd prdump prole updrow prindex
 noinst_HEADERS = base64.h
 LIBS	=	$(GLIB_LIBS) @LIBS@
 DEFS = @DEFS@ -DLOCALEDIR=\"$(localedir)\"
 AM_CFLAGS	=	-I$(top_srcdir)/include $(GLIB_CFLAGS) -Wsign-compare
 LDADD	=	../libmdb/libmdb.la 
-if SQL
+if ENABLE_SQL
+bin_PROGRAMS	+=	mdb-sql
 mdb_sql_LDADD = ../libmdb/libmdb.la ../sql/libmdbsql.la $(LIBREADLINE)
 endif

src/util/mdb-sql.c

@@ -51,8 +51,6 @@ extern void clear_history ();
 void dump_results(FILE *out, MdbSQL *sql, char *delimiter);
 void dump_results_pp(FILE *out, MdbSQL *sql);
 
-#if SQL
-
 int headers = 1;
 int footers = 1;
 int pretty_print = 1;
@@ -516,11 +514,3 @@ main(int argc, char **argv)
 
 	return 0;
 }
-#else
-int main(int argc, char **argv)
-{
-	fprintf(stderr,"You must configure using --enable-sql to get SQL support\n");
-
-	return -1;
-}
-#endif