Merge branch 'dev' of github.com:mdbtools/mdbtools into merge-166

src/sql/Makefile.am

@@ -3,7 +3,7 @@ BUILT_SOURCES = parser.h
 AM_YFLAGS = -d -o parser.c
 lib_LTLIBRARIES	=	libmdbsql.la
 libmdbsql_la_SOURCES=	mdbsql.c parser.y lexer.l 
-libmdbsql_la_LDFLAGS = -version-info 2:0:0 -export-symbols-regex '^mdb_sql_'
+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)

src/sql/lexer.l

@@ -72,6 +72,8 @@ null		{ return NUL; }
 ">"		{ return GT; }
 like		{ return LIKE; }
 limit		{ return LIMIT; }
+top		{ return TOP; }
+percent		{ return PERCENT; }
 count		{ return COUNT; }
 strptime	{ return STRPTIME; }
 [ \t\r]	;

src/sql/mdbsql.c

@@ -73,6 +73,7 @@ MdbSQL *sql;
 	sql->sarg_stack = NULL;
 	sql->max_rows = -1;
 	sql->limit = -1;
+	sql->limit_percent = 0;
 
 	return sql;
 }
@@ -189,12 +190,26 @@ MdbHandle *mdb_sql_open(MdbSQL *sql, char *db_name)
 
 #ifdef HAVE_WORDEXP
 	wordexp_t words;
+	int need_free_words = 0;
 
-	if (wordexp(db_name, &words, 0)==0) {
-		if (words.we_wordc>0) 
-			db_namep = words.we_wordv[0];
+	switch (wordexp(db_name, &words, 0))
+	{
+		case 0:
+			if (words.we_wordc>0)
+			{
+				db_namep = words.we_wordv[0];
+			}
+			need_free_words = 1;
+			break;
+		case WRDE_NOSPACE:
+			// If the error was WRDE_NOSPACE, then perhaps part of the result was allocated.
+			need_free_words = 1;
+			break;
+		default:
+			// Some other error
+			need_free_words = 0;
+			break;
 	}
-	
 #endif
 
 	sql->mdb = mdb_open(db_namep, MDB_NOFLAGS);
@@ -208,7 +223,10 @@ MdbHandle *mdb_sql_open(MdbSQL *sql, char *db_name)
 	}
 
 #ifdef HAVE_WORDEXP
-	wordfree(&words);
+	if ( need_free_words )
+	{
+		wordfree(&words);
+	}
 #endif	
 
 	return sql->mdb;
@@ -502,12 +520,23 @@ int mdb_sql_add_column(MdbSQL *sql, char *column_name)
 	sql->num_columns++;
 	return 0;
 }
-int mdb_sql_add_limit(MdbSQL *sql, char *limit)
+int mdb_sql_add_limit(MdbSQL *sql, char *limit, int percent)
 {
 	sql->limit = atoi(limit);
+	sql->limit_percent = percent;
+
+	if (sql->limit_percent && (sql->limit < 0 || sql->limit > 100)) {
+		return 1;
+	}
+
 	return 0;
 }
 
+int mdb_sql_get_limit(MdbSQL *sql)
+{
+	return sql->limit;
+}
+
 int mdb_sql_add_function1(MdbSQL *sql, char *func_name, char *arg1)
 {
 	fprintf(stderr, "calling function %s with %s", func_name, arg1);
@@ -833,6 +862,13 @@ int found = 0;
 
 	sql->cur_table = table;
 	mdb_index_scan_init(mdb, table);
+
+	/* We know how many rows there are, so convert limit percentage
+	 * to an row count */
+	if (sql->limit != -1 && sql->limit_percent) {
+		sql->limit = (int)((double)table->num_rows / 100 * sql->limit);
+		sql->limit_percent = 0;
+	}
 }
 
 void 

src/sql/parser.y

@@ -62,7 +62,7 @@ typedef struct sql_context
 
 %token <name> IDENT NAME PATH STRING NUMBER
 %token SELECT FROM WHERE CONNECT DISCONNECT TO LIST TABLES AND OR NOT LIMIT COUNT STRPTIME
-%token DESCRIBE TABLE
+%token DESCRIBE TABLE TOP PERCENT
 %token LTEQ GTEQ LIKE IS NUL
 
 %type <name> database
@@ -91,7 +91,7 @@ stmt:
 	;
 
 query:
-	SELECT column_list FROM table where_clause limit_clause {
+	SELECT top_clause column_list FROM table where_clause limit_clause {
 	                mdb_sql_select(parser_ctx->mdb);
 		}
 	|	CONNECT TO database { 
@@ -108,6 +108,17 @@ query:
 		}
 	;
 
+top_clause:
+	/* empty */
+	|	TOP NUMBER { mdb_sql_add_limit(parser_ctx->mdb, $2, 0); free($2); }
+	|	TOP NUMBER PERCENT {
+			if (mdb_sql_add_limit(parser_ctx->mdb, $2, 1)) {
+				yyerror(NULL, parser_ctx, "Percent values must be between 0 and 100");
+			}
+			free($2);
+		}
+	;
+
 where_clause:
 	/* empty */
 	| WHERE sarg_list
@@ -115,7 +126,14 @@ where_clause:
 
 limit_clause:
 	/* empty */
-	| LIMIT NUMBER { mdb_sql_add_limit(parser_ctx->mdb, $2); free($2); }
+	| LIMIT NUMBER {
+			if (mdb_sql_get_limit(parser_ctx->mdb) != -1) {
+				yyerror(NULL, parser_ctx, "Can not have TOP and LIMIT clauses");
+			} else {
+				mdb_sql_add_limit(parser_ctx->mdb, $2, 0);
+			}
+			free($2);
+		}
 	;
 
 sarg_list: