First cut of sarg (search argument) support.

TODO

@@ -9,6 +9,8 @@ Things to Do
 . Get automake working
 . Check out text file unixODBC driver to see if it can be adapted to use
   libmdb (it already has a SQL parser).
-. Straighten out which functions in libmdb are meant to be used and which ones
-  should be static.
+. Straighten out which functions in libmdb are meant to be used and which   ones should be static.
 . Create an API reference for libmdb (maybe some man pages).
+. Sargs need to support all datatypes
+. Need a way to express logical relationships between sargs (tree)
+. Add support for index scanning when using sargs

src/include/mdbtools.h

@@ -69,6 +69,17 @@ enum {
 	MDB_REPID = 0x0f
 };
 
+/* SARG operators */
+enum {
+	MDB_EQUAL = 1,
+	MDB_GT,
+	MDB_LT,
+	MDB_GTEQ,
+	MDB_LTEQ,
+	MDB_ISNULL,
+	MDB_NOTNULL
+};
+
 /* hash to store registered backends */
 GHashTable	*mdb_backends;
 
@@ -129,9 +140,22 @@ typedef struct {
 	int		col_size;
 	void		*bind_ptr;
 	GHashTable	*properties;
+	int		num_sargs;
+	GPtrArray	*sargs;
 	unsigned char   is_fixed;
 } MdbColumn;
 
+typedef union {
+	int	i;
+	double	d;
+	char	s[256];
+} MdbAny;
+
+typedef struct {
+	int	op;
+	MdbAny	value;
+} MdbSarg;
+
 /* mem.c */
 extern void mdb_init();
 extern void mdb_exit();

src/libmdb/Makefile.in

@@ -20,7 +20,7 @@ INSTALL= @INSTALL@
 LIBLIST = libmdb.a
 
 INC = -I ../include `glib-config --cflags`
-OBJS = catalog.o mem.o file.o kkd.o table.o data.o dump.o backend.o money.o
+OBJS = catalog.o mem.o file.o kkd.o table.o data.o dump.o backend.o money.o sargs.o
 
 all: libmdb
 
@@ -53,5 +53,6 @@ file.o: file.c ../include/mdbtools.h
 kkd.o: kkd.c ../include/mdbtools.h
 mem.o: mem.c ../include/mdbtools.h
 table.o: table.c ../include/mdbtools.h
+sargs.o: sargs.c ../include/mdbtools.h
 money.o: money.c 
 

src/libmdb/data.c

@@ -20,6 +20,8 @@
 #include "mdbtools.h"
 
 char *mdb_money_to_string(MdbHandle *mdb, int start, char *s);
+static int _mdb_attempt_bind(MdbHandle *mdb, 
+	MdbColumn *col, unsigned char isnull, int offset, int len);
 
 #define MDB_DEBUG 0
 
@@ -92,7 +94,7 @@ int mdb_read_row(MdbTableDef *table, int row)
 {
 MdbHandle *mdb = table->entry->mdb;
 MdbColumn *col;
-int i, j;
+int i, j, rc;
 int num_cols, var_cols, fixed_cols;
 int row_start, row_end;
 int fixed_cols_found, var_cols_found;
@@ -102,6 +104,7 @@ int eod; /* end of data */
 int delflag, lookupflag;
 int bitmask_sz;
 unsigned char null_mask[33]; /* 256 columns max / 8 bits per byte */
+unsigned char isnull;
 
 	row_start = mdb_get_int16(mdb, 10+(row*2)); 
 	row_end = mdb_find_end_of_row(mdb, row);
@@ -157,13 +160,10 @@ unsigned char null_mask[33]; /* 256 columns max / 8 bits per byte */
 		col = g_ptr_array_index(table->columns,j);
 		if (mdb_is_fixed_col(col) &&
 		    ++fixed_cols_found <= fixed_cols) {
-			if (col->col_type == MDB_BOOL) {
-				mdb_xfer_bound_bool(mdb, col, mdb_is_null(null_mask, j+1));
-			} else if (mdb_is_null(null_mask, j+1)) {
-				mdb_xfer_bound_data(mdb, 0, col, 0);
-			} else {
-				mdb_xfer_bound_data(mdb,row_start + col_start, col, col->col_size);
-			}
+			isnull = mdb_is_null(null_mask, j+1); 
+			rc = _mdb_attempt_bind(mdb, col, isnull,
+				row_start + col_start, col->col_size);
+			if (!rc) return 0;
 			col_start += col->col_size;
 		}
 	}
@@ -208,19 +208,34 @@ unsigned char null_mask[33]; /* 256 columns max / 8 bits per byte */
 					- var_cols_found 
 					- 1 - num_of_jumps ] - col_start;
 
-			if (col->col_type == MDB_BOOL) {
-				mdb_xfer_bound_bool(mdb, col, mdb_is_null(null_mask, j+1));
-			} else if (mdb_is_null(null_mask, j+1)) {
-				mdb_xfer_bound_data(mdb, 0, col, 0);
-			} else {
-				mdb_xfer_bound_data(mdb,row_start + col_start, col, len);
-			}
+			isnull = mdb_is_null(null_mask, j+1); 
+			rc = _mdb_attempt_bind(mdb, col, isnull,
+				row_start + col_start, len);
+			if (!rc) return 0;
 			col_start += len;
 		}
 	}
 
 	return 1;
 }
+static int _mdb_attempt_bind(MdbHandle *mdb, 
+	MdbColumn *col, 
+	unsigned char isnull, 
+	int offset, 
+	int len)
+{
+	if (col->col_type == MDB_BOOL) {
+		mdb_xfer_bound_bool(mdb, col, isnull);
+	} else if (isnull) {
+		mdb_xfer_bound_data(mdb, 0, col, 0);
+	} else {
+		if (!mdb_test_sargs(mdb, col, offset, len)) {
+			return 0;
+		}
+		mdb_xfer_bound_data(mdb, offset, col, len);
+	}
+	return 1;
+}
 int mdb_read_next_dpg(MdbTableDef *table)
 {
 MdbCatalogEntry *entry = table->entry;
@@ -242,6 +257,7 @@ int mdb_fetch_row(MdbTableDef *table)
 {
 MdbHandle *mdb = table->entry->mdb;
 int rows;
+int rc;
 
 	if (table->num_rows==0)
 		return 0;
@@ -253,18 +269,19 @@ int rows;
 		mdb_read_next_dpg(table);
 	}
 
-	rows = mdb_get_int16(mdb,8);
+	do { 
+		rows = mdb_get_int16(mdb,8);
 
-	/* if at end of page, find a new page */
-	if (table->cur_row >= rows) {
-		table->cur_row=0;
-		if (!mdb_read_next_dpg(table)) return 0;
-	}
+		/* if at end of page, find a new page */
+		if (table->cur_row >= rows) {
+			table->cur_row=0;
+			if (!mdb_read_next_dpg(table)) return 0;
+		}
 
-	mdb_read_row(table, 
-		table->cur_row);
+		rc = mdb_read_row(table, table->cur_row);
+		table->cur_row++;
+	} while (!rc);
 
-	table->cur_row++;
 	return 1;
 }
 void mdb_data_dump(MdbTableDef *table)

src/libmdb/sargs.c

@@ -0,0 +1,101 @@
+/* MDB Tools - A library for reading MS Access database file
+ * Copyright (C) 2000 Brian Bruns
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with this library; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ */
+
+#include "mdbtools.h"
+
+int mdb_test_int(MdbSarg *sarg, gint32 i)
+{
+	switch (sarg->op) {
+		case MDB_EQUAL:
+			if (sarg->value.i == i) return 1;
+			break;
+		case MDB_GT:
+			if (sarg->value.i < i) return 1;
+			break;
+		case MDB_LT:
+			if (sarg->value.i > i) return 1;
+			break;
+		case MDB_GTEQ:
+			if (sarg->value.i <= i) return 1;
+			break;
+		case MDB_LTEQ:
+			if (sarg->value.i >= i) return 1;
+			break;
+		default:
+			fprintf(stderr, "Calling mdb_test_sarg on unknown operator.  Add code to mdb_test_int() for operator %d\n",sarg->op);
+			break;
+	}
+	return 0;
+}
+int mdb_test_sarg(MdbHandle *mdb, MdbColumn *col, MdbSarg *sarg, int offset, int len)
+{
+	switch (col->col_type) {
+		case MDB_INT:
+			return mdb_test_int(sarg, mdb_get_int16(mdb, offset));
+			break;
+		case MDB_LONGINT:
+			return mdb_test_int(sarg, mdb_get_int32(mdb, offset));
+			break;
+		default:
+			fprintf(stderr, "Calling mdb_test_sarg on unknown type.  Add code to mdb_test_sarg() for type %d\n",col->col_type);
+			break;
+	}
+	return 1;
+}
+int mdb_test_sargs(MdbHandle *mdb, MdbColumn *col, int offset, int len)
+{
+MdbSarg *sarg;
+int i;
+
+	for (i=0;i<col->num_sargs;i++) {
+		sarg = g_ptr_array_index (col->sargs, i);
+		if (!mdb_test_sarg(mdb, col, sarg, offset, len)) {
+			/* sarg didn't match, no sense going on */
+			return 0;	
+		}
+	}
+
+	return 1;
+}
+int mdb_add_sarg(MdbColumn *col, MdbSarg *in_sarg)
+{
+MdbSarg *sarg;
+        if (!col->sargs) {
+		col->sargs = g_ptr_array_new();
+	}
+	sarg = g_memdup(in_sarg,sizeof(MdbSarg));
+        g_ptr_array_add(col->sargs, sarg);
+	col->num_sargs++;
+
+	return 1;
+}
+int mdb_add_sarg_by_name(MdbTableDef *table, char *colname, MdbSarg *in_sarg)
+{
+MdbColumn *col;
+int i;
+
+	for (i=0;i<table->num_cols;i++) {
+		col = g_ptr_array_index (table->columns, i);
+		if (!strcmp(col->name,colname)) {
+			return mdb_add_sarg(col, in_sarg);
+		}
+	}
+	/* else didn't find the column return 0! */
+	return 0;
+}