MDEV-25726 get rid of cmake comment hack in sql_yacc.yy

and replace it with equally unsightly %ifdef/%endif hack
also, support %else, it's nice

.gitignore

@@ -198,6 +198,7 @@ sql/mysqld
 sql/sql_builtin.cc
 sql/sql_yacc.cc
 sql/sql_yacc.hh
+sql/sql_yacc_mariadb.yy
 sql/sql_yacc_ora.cc
 sql/sql_yacc_ora.hh
 sql/sql_yacc_ora.yy

sql/CMakeLists.txt

@@ -66,16 +66,17 @@ ADD_CUSTOM_COMMAND(
 )
 
 ADD_CUSTOM_COMMAND(
-  OUTPUT ${CMAKE_CURRENT_BINARY_DIR}/sql_yacc_ora.yy
-  COMMAND ${CMAKE_COMMAND}
+  OUTPUT ${CMAKE_CURRENT_BINARY_DIR}/sql_yacc_mariadb.yy
+         ${CMAKE_CURRENT_BINARY_DIR}/sql_yacc_ora.yy
+  COMMAND ${CMAKE_COMMAND} "-DVAL1=ORACLE" "-DVAL2=MARIADB"
+   "-DOUT1=${CMAKE_CURRENT_BINARY_DIR}/sql_yacc_ora.yy"
+   "-DOUT2=${CMAKE_CURRENT_BINARY_DIR}/sql_yacc_mariadb.yy"
    "-DIN=${CMAKE_CURRENT_SOURCE_DIR}/sql_yacc.yy"
-   "-DOUT=${CMAKE_CURRENT_BINARY_DIR}/sql_yacc_ora.yy"
-   -P ${CMAKE_CURRENT_SOURCE_DIR}/gen_sql_yacc_ora_yy.cmake
+   -P ${CMAKE_CURRENT_SOURCE_DIR}/gen_yy_files.cmake
   DEPENDS ${CMAKE_CURRENT_SOURCE_DIR}/sql_yacc.yy
+          ${CMAKE_CURRENT_SOURCE_DIR}/gen_yy_files.cmake
 )
 
-ADD_CUSTOM_TARGET(gen_sql_yacc_ora_yy DEPENDS ${CMAKE_CURRENT_BINARY_DIR}/sql_yacc_ora.yy)
-
 ADD_DEFINITIONS(-DMYSQL_SERVER -DHAVE_EVENT_SCHEDULER)
 
 IF(SSL_DEFINES)
@@ -350,10 +351,13 @@ IF (NOT BISON_FOUND)
       MESSAGE(FATAL_ERROR ${ERRMSG})
   ENDIF()
 ELSE()
-  BISON_TARGET(gen_sql_yacc ${CMAKE_CURRENT_SOURCE_DIR}/sql_yacc.yy ${CMAKE_CURRENT_BINARY_DIR}/sql_yacc.cc
-             COMPILE_FLAGS "-p MYSQL")
-  BISON_TARGET(gen_sql_yacc_ora ${CMAKE_CURRENT_BINARY_DIR}/sql_yacc_ora.yy ${CMAKE_CURRENT_BINARY_DIR}/sql_yacc_ora.cc
-             COMPILE_FLAGS "-p ORA")
+  BISON_TARGET(gen_mariadb_cc_hh ${CMAKE_CURRENT_BINARY_DIR}/sql_yacc_mariadb.yy
+                                 ${CMAKE_CURRENT_BINARY_DIR}/sql_yacc.cc
+                    DEFINES_FILE ${CMAKE_CURRENT_BINARY_DIR}/sql_yacc.hh
+               COMPILE_FLAGS "-p MYSQL -S ${CMAKE_CURRENT_SOURCE_DIR}/myskel.m4")
+  BISON_TARGET(gen_oracle_cc_hh ${CMAKE_CURRENT_BINARY_DIR}/sql_yacc_ora.yy
+                                ${CMAKE_CURRENT_BINARY_DIR}/sql_yacc_ora.cc
+               COMPILE_FLAGS "-p ORA -S ${CMAKE_CURRENT_SOURCE_DIR}/myskel.m4")
 ENDIF()
 
 IF(NOT CMAKE_CROSSCOMPILING OR DEFINED CMAKE_CROSSCOMPILING_EMULATOR)
@@ -377,11 +381,10 @@ ADD_CUSTOM_TARGET(
         DEPENDS
         ${CMAKE_CURRENT_BINARY_DIR}/lex_hash.h
         ${CMAKE_CURRENT_BINARY_DIR}/lex_token.h
+        ${CMAKE_CURRENT_BINARY_DIR}/sql_yacc.cc
         ${CMAKE_CURRENT_BINARY_DIR}/sql_yacc_ora.cc
 )
 
-ADD_DEPENDENCIES(GenServerSource gen_sql_yacc_ora_yy)
-
 IF(WIN32 OR HAVE_DLOPEN AND NOT DISABLE_SHARED)
   ADD_LIBRARY(udf_example MODULE udf_example.c udf_example.def)
   SET_TARGET_PROPERTIES(udf_example PROPERTIES PREFIX "")

sql/gen_sql_yacc_ora_yy.cmake

-
-file(READ "${IN}" yytmp)
-
-# Comment out sql_mode=DEFAULT rules and directives (e.g. %expect, %type)
-string(REPLACE  "/* Start SQL_MODE_DEFAULT_SPECIFIC */"
-                "/* Start SQL_MODE_DEFAULT_SPECIFIC"      yytmp "${yytmp}")
-string(REPLACE  "/* End SQL_MODE_DEFAULT_SPECIFIC */"
-                   "End SQL_MODE_DEFAULT_SPECIFIC */"     yytmp "${yytmp}")
-
-# Uncomment sql_mode=ORACLE rules and directives
-string(REPLACE  "/* Start SQL_MODE_ORACLE_SPECIFIC"
-                "/* Start SQL_MODE_ORACLE_SPECIFIC */"    yytmp "${yytmp}")
-string(REPLACE     "End SQL_MODE_ORACLE_SPECIFIC */"
-                "/* End SQL_MODE_ORACLE_SPECIFIC */"      yytmp "${yytmp}")
-file(WRITE "${OUT}" "${yytmp}")

sql/gen_yy_files.cmake

+if(POLICY CMP0054)
+  cmake_policy(SET CMP0054 NEW)
+endif()
+file(READ "${IN}" data)
+file(WRITE "${OUT1}" "")
+file(WRITE "${OUT2}" "")
+set(where 0)
+string(REGEX REPLACE "/\\* sql_yacc\\.yy \\*/" "/* DON'T EDIT THIS FILE. IT'S GENERATED.  EDIT sql_yacc.yy INSTEAD */" data "${data}")
+while(NOT data STREQUAL "")
+  string(REGEX MATCH "^(%[ie][^\n]*\n)|((%[^ie\n]|[^%\n])[^\n]*\n)+|\n+" line "${data}")
+  string(LENGTH "${line}" ll)
+  string(SUBSTRING "${data}" ${ll} -1 data)
+
+  if (line MATCHES "^%ifdef +${VAL1} *\n")
+    set(where 1)
+    set(line "\n")
+  elseif(line MATCHES "^%ifdef +${VAL2} *\n")
+    set(where 2)
+    set(line "\n")
+  elseif(line MATCHES "^%else( *| +.*)\n" AND where GREATER 0)
+    math(EXPR where "3-${where}")
+    set(line "\n")
+  elseif(line MATCHES "^%endif( *| +.*)\n")
+    set(where 0)
+    set(line "\n")
+  endif()
+  if(where STREQUAL 1)
+    file(APPEND "${OUT1}" "${line}")
+    string(REGEX REPLACE "[^\n]+" "" line "${line}")
+    file(APPEND "${OUT2}" "${line}")
+  elseif(where STREQUAL 2)
+    file(APPEND "${OUT2}" "${line}")
+    string(REGEX REPLACE "[^\n]+" "" line "${line}")
+    file(APPEND "${OUT1}" "${line}")
+  else()
+    file(APPEND "${OUT1}" "${line}")
+    file(APPEND "${OUT2}" "${line}")
+  endif()
+endwhile()

sql/myskel.m4

+#
+# fix the #line directives in the generated .cc files
+# to refer to the original sql_yacc.yy
+#
+m4_define([yyfile],m4_bpatsubst(__file__,[[a-z.0-9]+$],sql_yacc.yy))
+
+m4_define([b4_syncline],
+[m4_if(m4_index([$2],[.yy]),[-1],
+[b4_sync_start([$1], [$2])[]dnl
+
+],[b4_sync_start([$1], ["yyfile"])[]dnl
+
+])])
+
+# try both paths for different bison versions
+m4_sinclude(skeletons/c-skel.m4)
+m4_sinclude(c-skel.m4)
+

sql/sql_lex.h

@@ -355,7 +355,7 @@ void binlog_unsafe_map_init();
 
 #ifdef MYSQL_SERVER
 /*
-  The following hack is needed because mysql_yacc.cc does not define
+  The following hack is needed because sql_yacc.cc does not define
   YYSTYPE before including this file
 */
 #ifdef MYSQL_YACC

sql/sql_yacc.yy

@@ -341,14 +341,11 @@ bool my_yyoverflow(short **a, YYSTYPE **b, size_t *yystacksize);
   We should not introduce any further shift/reduce conflicts.
 */
 
-/* Start SQL_MODE_DEFAULT_SPECIFIC */
+%ifdef MARIADB
 %expect 67
-/* End SQL_MODE_DEFAULT_SPECIFIC */
-
-
-/* Start SQL_MODE_ORACLE_SPECIFIC
+%else
 %expect 69
-End SQL_MODE_ORACLE_SPECIFIC */
+%endif
 
 
 /*
@@ -1766,7 +1763,7 @@ End SQL_MODE_ORACLE_SPECIFIC */
 %type <vers_history_point> history_point
 %type <vers_column_versioning> with_or_without_system
 
-/* Start SQL_MODE_DEFAULT_SPECIFIC */
+%ifdef MARIADB
 %type <NONE> sp_tail_standalone
 %type <NONE> sp_unlabeled_block_not_atomic
 %type <NONE> sp_proc_stmt_in_returns_clause
@@ -1778,10 +1775,7 @@ End SQL_MODE_ORACLE_SPECIFIC */
 %type <spblock> sp_decl_variable_list
 %type <spblock> sp_decl_variable_list_anchored
 %type <kwd> reserved_keyword_udt_param_type
-/* End SQL_MODE_DEFAULT_SPECIFIC */
-
-
-/* Start SQL_MODE_ORACLE_SPECIFIC
+%else
 %type <NONE> set_assign
 %type <spvar_mode> sp_opt_inout
 %type <NONE> sp_tail_standalone
@@ -1816,7 +1810,7 @@ End SQL_MODE_ORACLE_SPECIFIC */
 %type <lex> package_routine_lex
 %type <lex> package_specification_function
 %type <lex> package_specification_procedure
-End SQL_MODE_ORACLE_SPECIFIC */
+%endif ORACLE
 
 %%
 
@@ -17809,7 +17803,7 @@ _empty:
           /* Empty */
         ;
 
-/* Start SQL_MODE_DEFAULT_SPECIFIC */
+%ifdef MARIADB
 
 
 statement:
@@ -18208,10 +18202,10 @@ sp_unlabeled_block_not_atomic:
         ;
 
 
-/* End SQL_MODE_DEFAULT_SPECIFIC */
+%endif MARIADB
 
 
-/* Start SQL_MODE_ORACLE_SPECIFIC
+%ifdef ORACLE
 
 statement:
           verb_clause
@@ -19220,7 +19214,7 @@ sp_block_statements_and_exceptions:
           }
         ;
 
-End SQL_MODE_ORACLE_SPECIFIC */
+%endif ORACLE
 
 /**
   @} (end of group Parser)