WIP: sqlite3: Add decoder

See sqlite3.{go,jq} for TODO

Related to #27

format/all/all.go

@@ -26,6 +26,7 @@ import (
 	_ "github.com/wader/fq/format/png"
 	_ "github.com/wader/fq/format/protobuf"
 	_ "github.com/wader/fq/format/raw"
+	_ "github.com/wader/fq/format/sqlite3"
 	_ "github.com/wader/fq/format/tar"
 	_ "github.com/wader/fq/format/tiff"
 	_ "github.com/wader/fq/format/vorbis"

format/format.go

@@ -88,6 +88,8 @@ const (
 	WAV                 = "wav"
 	WEBP                = "webp"
 	ZIP                 = "zip"
+
+	SQLITE3 = "sqlite3"
 )
 
 // below are data types used to communicate between formats <FormatName>In/Out

format/sqlite3/sqlite3.go

@@ -0,0 +1,274 @@
+package sqlite3
+
+// https://www.sqlite.org/fileformat.html
+// https://sqlite.org/schematab.html
+
+// TODO: page overflow
+// TODO: format version
+// TODO: text encoding
+// TODO: table/column names
+// TODO: assert version and schema version?
+// TODO: ptrmap
+// TODO: how to represent NULL serials
+
+// CREATE TABLE sqlite_schema(
+// 	type text,
+// 	name text,
+// 	tbl_name text,
+// 	rootpage integer,
+// 	sql text
+// );
+// > A table with the name "sqlite_sequence" that is used to keep track of the maximum historical INTEGER PRIMARY KEY for a table using AUTOINCREMENT.
+// CREATE TABLE sqlite_sequence(name,seq);
+// > Tables with names of the form "sqlite_statN" where N is an integer. Such tables store database statistics gathered by the ANALYZE command and used by the query planner to help determine the best algorithm to use for each query.
+// CREATE TABLE sqlite_stat1(tbl,idx,stat);
+// Only if compiled with SQLITE_ENABLE_STAT2:
+// CREATE TABLE sqlite_stat2(tbl,idx,sampleno,sample);
+// Only if compiled with SQLITE_ENABLE_STAT3:
+// CREATE TABLE sqlite_stat3(tbl,idx,nEq,nLt,nDLt,sample);
+// Only if compiled with SQLITE_ENABLE_STAT4:
+// CREATE TABLE sqlite_stat4(tbl,idx,nEq,nLt,nDLt,sample);
+// TODO: sqlite_autoindex_TABLE_N index
+
+import (
+	"embed"
+
+	"github.com/wader/fq/format"
+	"github.com/wader/fq/format/registry"
+	"github.com/wader/fq/internal/num"
+	"github.com/wader/fq/pkg/decode"
+	"github.com/wader/fq/pkg/scalar"
+)
+
+//go:embed *.jq
+var sqlite3FS embed.FS
+
+func init() {
+	registry.MustRegister(decode.Format{
+		Name:        format.SQLITE3,
+		Description: "SQLite v3 database",
+		Groups:      []string{format.PROBE},
+		DecodeFn:    sqlite3Decode,
+		Files:       sqlite3FS,
+	})
+}
+
+const (
+	bTreeIndexInterior = 0x02
+	bTreeTableInterior = 0x05
+	bTreeIndexLeaf     = 0x0a
+	bTreeTableLeaf     = 0x0d
+)
+
+var bTreeTypeMap = scalar.UToScalar{
+	bTreeIndexInterior: scalar.S{Sym: "index_interior", Description: "Index interior b-tree page"},
+	bTreeTableInterior: scalar.S{Sym: "table_interior", Description: "Table interior b-tree page"},
+	bTreeIndexLeaf:     scalar.S{Sym: "index_leaf", Description: "Index leaf b-tree page"},
+	bTreeTableLeaf:     scalar.S{Sym: "table_leaf", Description: "Table leaf b-tree page"},
+}
+
+const (
+	textEncodingUTF8    = 1
+	textEncodingUTF16LE = 2
+	textEncodingUTF16BE = 3
+)
+
+var textEncodingMap = scalar.UToSymStr{
+	textEncodingUTF8:    "utf8",
+	textEncodingUTF16LE: "utf16le",
+	textEncodingUTF16BE: "utf16be",
+}
+
+var versionMap = scalar.UToSymStr{
+	1: "legacy",
+	2: "wal",
+}
+
+// TODO: all bits if nine bytes?
+// TODO: two complement on bit read count
+func varintDecode(d *decode.D) int64 {
+	var n uint64
+	for i := 0; i < 9; i++ {
+		v := d.U8()
+		n = n<<7 | v&0b0111_1111
+		if v&0b1000_0000 == 0 {
+			break
+		}
+	}
+	return num.TwosComplement(64, n)
+}
+
+func sqlite3DecodeSerialType(d *decode.D, typ int64) {
+	switch typ {
+	case 0:
+		d.FieldValueStr("value", "NULL", scalar.Description("null"))
+	case 1:
+		d.FieldS8("value", scalar.Description("8-bit integer"))
+	case 2:
+		d.FieldS16("value", scalar.Description("16-bit integer"))
+	case 3:
+		d.FieldS24("value", scalar.Description("24-bit integer"))
+	case 4:
+		d.FieldS32("value", scalar.Description("32-bit integer"))
+	case 5:
+		d.FieldS48("value", scalar.Description("48-bit integer"))
+	case 6:
+		d.FieldS64("value", scalar.Description("64-bit integer"))
+	case 7:
+		d.FieldF64("value", scalar.Description("64-bit float"))
+	case 8:
+		d.FieldValueU("value", 0, scalar.Description("constant 0"))
+	case 9:
+		d.FieldValueU("value", 1, scalar.Description("constant 1"))
+	case 10, 11:
+	default:
+		if typ%2 == 0 {
+			// N => 12 and even: (N-12)/2 bytes blob.
+			d.FieldRawLen("value", (typ-12)/2*8, scalar.Description("blob"))
+		} else {
+			// N => 13 and odd: (N-13)/2 bytes text
+			d.FieldUTF8("value", int(typ-13)/2, scalar.Description("text"))
+		}
+	}
+}
+
+func sqlite3CellFreeblockDecode(d *decode.D) uint64 {
+	nextOffset := d.FieldU16("next_offset")
+	if nextOffset == 0 {
+		return 0
+	}
+	// TODO: "header" is size bytes or offset+size? seems to be just size
+	// "size of the freeblock in bytes, including the 4-byte header"
+	size := d.FieldU16("size")
+	d.FieldRawLen("space", int64(size-4)*8)
+	return nextOffset
+}
+
+func sqlite3CellPayloadDecode(d *decode.D) {
+	lengthStart := d.Pos()
+	length := d.FieldSFn("length", varintDecode)
+	lengtbBits := d.Pos() - lengthStart
+	var serialTypes []int64
+	d.LenFn((length)*8-lengtbBits, func(d *decode.D) {
+		d.FieldArray("serials", func(d *decode.D) {
+			for !d.End() {
+				serialTypes = append(serialTypes, d.FieldSFn("serial", varintDecode))
+			}
+		})
+	})
+	d.FieldArray("contents", func(d *decode.D) {
+		for _, s := range serialTypes {
+			sqlite3DecodeSerialType(d, s)
+		}
+	})
+}
+
+func sqlite3Decode(d *decode.D, in interface{}) interface{} {
+	var pageSizeS *scalar.S
+	var databaseSizePages uint64
+
+	d.FieldStruct("header", func(d *decode.D) {
+		d.FieldUTF8("magic", 16, d.AssertStr("SQLite format 3\x00"))
+		pageSizeS = d.FieldScalarU16("page_size", scalar.UToSymU{1: 65536}) // in bytes. Must be a power of two between 512 and 32768 inclusive, or the value 1 representing a page size of 65536.
+		d.FieldU8("write_version", versionMap)                              // 1 for legacy; 2 for WAL.
+		d.FieldU8("read_version", versionMap)                               // . 1 for legacy; 2 for WAL.
+		d.FieldU8("unused_space")                                           // at the end of each page. Usually 0.
+		d.FieldU8("maximum_embedded_payload_fraction")                      // . Must be 64.
+		d.FieldU8("minimum_embedded_payload_fraction")                      // . Must be 32.
+		d.FieldU8("leaf_payload_fraction")                                  // . Must be 32.
+		d.FieldU32("file_change_counter")                                   //
+		databaseSizePages = d.FieldU32("database_size_pages")               // . The "in-header database size".
+		d.FieldU32("page_number_freelist")                                  // of the first freelist trunk page.
+		d.FieldU32("total_number_freelist")                                 // pages.
+		d.FieldU32("schema_cookie")                                         // .
+		d.FieldU32("schema_format_number")                                  // . Supported schema formats are 1, 2, 3, and 4.
+		d.FieldU32("default_page_cache_size")                               // .
+		d.FieldU32("page_number_largest_root_btree")                        // page when in auto-vacuum or incremental-vacuum modes, or zero otherwise.
+		d.FieldU32("text_encoding", textEncodingMap)
+		d.FieldU32("user_version")                       // " as read and set by the user_version pragma.
+		d.FieldU32("incremental_vacuum_mode")            // False (zero) otherwise.
+		d.FieldU32("application_id")                     // " set by PRAGMA application_id.
+		d.FieldRawLen("reserved", 160, d.BitBufIsZero()) // for expansion. Must be zero.
+		d.FieldU32("version_valid_for")                  // number.
+		d.FieldU32("sqlite_version_number")              //
+	})
+
+	// TODO: nicer API for fallback?
+	pageSize := pageSizeS.ActualU()
+	if pageSizeS.Sym != nil {
+		pageSize = pageSizeS.SymU()
+	}
+
+	d.FieldArray("pages", func(d *decode.D) {
+		for i := uint64(0); i < databaseSizePages; i++ {
+			pageOffset := int64(pageSize) * int64(i)
+			d.SeekAbs(pageOffset * 8)
+			// skip header for first page
+			if i == 0 {
+				d.SeekRel(100 * 8)
+			}
+
+			d.FieldStruct("page", func(d *decode.D) {
+				typ := d.FieldU8("type", bTreeTypeMap)
+				startFreeblocks := d.FieldU16("start_freeblocks") // The two-byte integer at offset 1 gives the start of the first freeblock on the page, or is zero if there are no freeblocks.
+				pageCells := d.FieldU16("page_cells")             // The two-byte integer at offset 3 gives the number of cells on the page.
+				d.FieldU16("cell_start")                          // sThe two-byte integer at offset 5 designates the start of the cell content area. A zero value for this integer is interpreted as 65536.
+				d.FieldU8("cell_fragments")                       // The one-byte integer at offset 7 gives the number of fragmented free bytes within the cell content area.
+				switch typ {
+				case bTreeIndexInterior,
+					bTreeTableInterior:
+					d.FieldU32("right_pointer") // The four-byte page number at offset 8 is the right-most pointer. This value appears in the header of interior b-tree pages only and is omitted from all other pages.
+				}
+				var cellPointers []uint64
+				d.FieldArray("cells_pointers", func(d *decode.D) {
+					for i := uint64(0); i < pageCells; i++ {
+						cellPointers = append(cellPointers, d.FieldU16("pointer"))
+					}
+				})
+				if startFreeblocks != 0 {
+					d.FieldArray("freeblocks", func(d *decode.D) {
+						nextOffset := startFreeblocks
+						for nextOffset != 0 {
+							d.SeekAbs((pageOffset + int64(nextOffset)) * 8)
+							d.FieldStruct("freeblock", func(d *decode.D) {
+								nextOffset = sqlite3CellFreeblockDecode(d)
+							})
+						}
+					})
+				}
+				d.FieldArray("cells", func(d *decode.D) {
+					for _, p := range cellPointers {
+						d.FieldStruct("cell", func(d *decode.D) {
+							// TODO: SeekAbs with fn later?
+							d.SeekAbs((pageOffset + int64(p)) * 8)
+							switch typ {
+							case bTreeIndexInterior:
+								d.FieldU32("left_child")
+								payLoadLen := d.FieldSFn("payload_len", varintDecode)
+								d.LenFn(payLoadLen*8, func(d *decode.D) {
+									d.FieldStruct("payload", sqlite3CellPayloadDecode)
+								})
+							case bTreeTableInterior:
+								d.FieldU32("left_child")
+								d.FieldSFn("rowid", varintDecode)
+							case bTreeIndexLeaf:
+								payLoadLen := d.FieldSFn("payload_len", varintDecode)
+								d.LenFn(payLoadLen*8, func(d *decode.D) {
+									d.FieldStruct("payload", sqlite3CellPayloadDecode)
+								})
+							case bTreeTableLeaf:
+								payLoadLen := d.FieldSFn("payload_len", varintDecode)
+								d.FieldSFn("rowid", varintDecode)
+								d.LenFn(payLoadLen*8, func(d *decode.D) {
+									d.FieldStruct("payload", sqlite3CellPayloadDecode)
+								})
+							}
+						})
+					}
+				})
+			})
+		}
+	})
+
+	return nil
+}

format/sqlite3/sqlite3.jq

@@ -0,0 +1,41 @@
+
+# TODO: two columns tables are index tables?
+# TODO: why page numbers-1? 0 excluded as special?
+# TODO: traverse is wrong somehow
+# TODO:   chinook.db => [sqlite3_table("Track")] | length => 3496, should be 3503 rows
+
+def sqlite3_traverse($root; $page):
+  def _t:
+    ( . # debug({TRAVESE: .})
+    | if .type == "table_interior" or .type == "index_interior" then
+        ( $root.pages[.cells[].left_child-1, .right_pointer-1]
+        | _t
+        )
+      elif .type == "table_leaf" or .type == "index_leaf" then
+        ( .cells[]
+        )
+      end
+    );
+  ( $page
+  | _t
+  );
+
+def sqlite3_table($name):
+  ( . as $root
+  | ( first(
+        ( sqlite3_traverse($root; $root.pages[0])
+        | select(.payload.contents | .[0] == "table" and .[2] == $name)
+        )
+      )
+    ) as $table_start_cell
+  | ( first(
+        ( sqlite3_traverse($root; $root.pages[0])
+        | select(.payload.contents| .[0] == "index" and .[2] == $name)
+        )
+      )
+    ) as $index_start_cell
+  | sqlite3_traverse($root; $root.pages[$index_start_cell.payload.contents[3]-1]) as $index_row
+  | sqlite3_traverse($root; $root.pages[$table_start_cell.payload.contents[3]-1])
+  | first(select(.rowid == $index_row.payload.contents[1]))
+  | .payload.contents
+  );

format/sqlite3/testdata/test.sh

@@ -0,0 +1,3 @@
+#!/bin/sh
+
+cat test.sql | sqlite3 test.db

format/sqlite3/testdata/test.sql

@@ -0,0 +1,18 @@
+CREATE TABLE aaa (
+    cint int primary key,
+    cvarchar varchar(30),
+    ctext text,
+    creal real,
+    cblob blob
+);
+INSERT INTO "aaa" VALUES(0, 'var1', 'text1', 0, "blob1");
+INSERT INTO "aaa" VALUES(1, 'var2', 'test2', 1, "blob2");
+INSERT INTO "aaa" VALUES(128, 'var3', 'test3', 128, "blob3");
+INSERT INTO "aaa" VALUES(-128, 'var3', 'test3', -128, "blob3");
+INSERT INTO "aaa" VALUES(9223372036854775807, 'var4', 'test4', 9223372036854775807, "blob4");
+INSERT INTO "aaa" VALUES(-9223372036854775808, 'var5', 'test5', -9223372036854775808, "blob5");
+
+-- CREATE TABLE aaa (
+--     cint int primary key
+-- );
+-- INSERT INTO "aaa" VALUES(123);