fix software to compile properly on Windows XP x86

1 files changed, 539 insertions, 529 deletions

diff --git a/wlb.c b/wlb.c
index 2876d48..c69c49c 100644
--- a/wlb.c
+++ b/wlb.c
@@ -1,531 +1,541 @@
-#include <windows.h>
-#include <stdlib.h>
-#include <tchar.h>
-#include "sqlite3.h"
-#include "sha-2/sha-256.h"
-#define SHASIZ SIZE_OF_SHA_256_HASH
-
-/* TODO: "\\?\" trick?
- * Windows limits path lengths to 260 characters. Explorer on Windows XP
- * has this issue too.
- *
- * UTF issues?
- */
-
-/*************************************************************************
- *  Compatability defines for non-Unicode systems
- ************************************************************************/
-
-#ifdef UNICODE
-# define ENCODING SQLITE3_UTF16
-# define sqlite3_open_U sqlite3_open16
-# define sqlite3_errmsg_U sqlite3_errmsg16
-# define sqlite3_bind_text_U sqlite3_bind_text16
-#else
-# define ENCODING SQLITE3_UTF8
-# define sqlite3_open_U sqlite3_open
-# define sqlite3_errmsg_U sqlite3_errmsg
-# define sqlite3_bind_text_U sqlite3_bind_text
-#endif
-
-/****************
- * Globals
- ***************/
-
-sqlite3 *g_db = NULL;
-int g_verbose = 0;
-sqlite_int64 g_backup_id = -1;
-
-/********************
- * Utility Functions
- *******************/
-
-static void _log(TCHAR *msg, ...)
-{
-	va_list va;
-
-	if (g_verbose) {
-		va_start(va, emsg);
-		_tvprintf(emsg, va);
-		va_end(va);
-	}
-}
-/* String literals only */
-#define log(msg, ...) _log(TEXT(msg), __VA_ARGS__)
-
-static void _die(TCHAR *emsg, ...)
-{
-	va_list va;
-	va_start(va, emsg);
-	_tvprintf(emsg, va);
-	va_end(va);
-
-	sqlite3_close(g_db);
-	exit(1);
-}
-/* String literals only */
-#define die(emsg, ...) _die(TEXT(emsg), __VA_ARGS__)
-
-/**********************************
- * Database constants
- *********************************/
-
-/* 'wlb' in ASCII */
-#define UPPER_VERSION 0x776c62
-#define CUR_VERSION 0x776c6201
-#define S(s) #s
-#define INIT_SCRIPT "\
-BEGIN; \
-PRAGMA user_version = " S(CUR_VERSION) ";\
-CREATE TABLE chunks (\
-	rowid INTEGER PRIMARY KEY, \
-	sha256 TEXT UNIQUE NOT NULL, \
-	data BLOB NOT NULL\
-); \
-CREATE TABLE backup_ids (\
-	ts TEXT UNIQUE NOT NULL,\
-	rowid INTEGER PRIMARY KEY\
-); \
-CREATE TABLE backups (\
-	backup INTEGER NOT NULL REFERENCES backup_ids ON DELETE CASCADE, \
-	path TEXT NOT NULL, \
-	chunk INTEGER NOT NULL REFERENCES chunks ON DELETE RESTRICT\
-); \
-CREATE INDEX backups_paths ON backups (path); \
-CREATE INDEX backups_backup ON backups (backup); \
-CREATE INDEX backups_chunk ON backups (chunk);\
-COMMIT;"
-
-/* Check if the database version is correct. If it is not correct
- * and the create flag is enabled, then initialize a new database.
- */
-static void check_db_version(int did_not_exist)
-{
-	int user_version;
-	sqlite3_stmt *stmt;
-
-	/* DB did not exist beforehand: initialize DB */
-	if (did_not_exist) {
-		if (sqlite3_exec(g_db, INIT_SCRIPT, NULL, NULL, NULL) != SQLITE_OK)
-			die("Error initializing database: %s\n",
-			    sqlite3_errmsg_U(g_db));
-		log("Intialized database\n");
-		return;
-	}
-
-	/* DB existed beforehand: do version check */
-	if (sqlite3_prepare_v2(g_db, "PRAGMA user_version;", -1, &stmt, NULL)
-	                       != SQLITE_OK)
-		die("Error preparing user version check: %s\n",
-		    sqlite3_errmsg_U(g_db));
-	if (sqlite3_step(stmt) != SQLITE_ROW)
-		die("Error executing user version check: %s\n",
-		    sqlite3_errmsg_U(g_db));
-	user_version = sqlite3_column_int(stmt, 0);
-	sqlite3_finalize(stmt);
-
-	if (user_version != CUR_VERSION) {
-		die("Bad DB version found (expected %d), got %d\n",
-		    CUR_VERSION & 0xFF, user_version & 0xFF);
-	}
-}
-
-/* Initialize the backup ID used in this session.
- * This is only called if the user requests an archive of a directory.
- */
-static void initialize_backup_id(void)
-{
-	sqlite3_stmt *stmt;
-
-	if (sqlite3_prepare(g_db,
-	                    "INSERT INTO backup_ids (ts) VALUES (datetime()) RETURNING rowid;",
-	                    -1, &stmt, NULL) != SQLITE_OK) {
-		die("failed to prepare inserting timestamp: %s\n",
-		    sqlite3_errmsg_U(g_db));
-	}
-
-	if (sqlite3_step(stmt) != SQLITE_ROW)
-		die("failed to insert timestamp: %s\n",
-		    sqlite3_errmsg_U(g_db));
-	g_backup_id = sqlite3_column_int64(stmt, 0);
-	sqlite3_finalize(stmt);
-}
-
-/* Opens the DB and initializes it if it did not exist. */
-static void open_db(TCHAR *fn)
-{
-	int did_not_exist = GetFileAttributes(fn)
-	                    == INVALID_FILE_ATTRIBUTES;
-	char *errmsg;
-
-	if (sqlite3_open_U(fn, &g_db) != SQLITE_OK)
-		die("Error opening database %s: %s\n", argv[i],
-		    sqlite3_errmsg_U(g_db));
-	check_db_version(did_not_exist);
-
-	/* Store current timestamp */
-	if (sqlite3_exec(g_db, "BEGIN;" NULL, NULL, &errmsg) != SQLITE_OK)
-		die("failed to begin transaction: %s\n", errmsg);
-}
-
-/* Insert a backup record into the database.
- *
- * This part occurs after the file data has been inserted or identified
- * by SHA256 hash.
- */
-static int insert_backup_record(TCHAR *name, sqlite_int64 chunk_id)
-{
-	sqlite3_stmt *stmt;
-	int r = 0;
-
-	if (sqlite3_prepare(g_db,
-	                    "INSERT INTO backups (backup, path, chunk) VALUES (?,?,?);",
-	                    -1, &stmt, NULL) != SQLITE_OK) {
-		_tprintf("Could not prepare backup insert statement for %s: %s\n",
-		         name, sqlite3_errmsg_U(g_db));
-		return 0;
-	}
-
-	if (sqlite3_bind_int64(stmt, 1, g_backup_id) != SQLITE_OK) {
-		_tprintf("Could not bind backup id for %s: %s\n", name,
-		         sqlite3_errmsg_U(g_db));
-		goto end;
-	}
-
-	if (sqlite3_bind_text_U(stmt, 2, name) != SQLITE_OK) {
-		_tprintf("Could not bind path for %s: %s\n", name,
-		         sqlite3_errmsg_U(g_db));
-		goto end;
-	}
-
-	if (sqlite3_bind_int64(stmt, 3, chunk_id) != SQLITE_OK) {
-		_tprintf("Could not bind chunk for %s: %s\n", name,
-		         sqlite3_errmsg_U(g_db));
-		goto end;
-	}
-
-	if (sqlite3_step(stmt) != SQLITE_DONE) {
-		_tprintf("Error in inserting chunk for %s: %s\n", name,
-		         sqlite3_errmsg_U(g_db));
-		goto end;
-	}
-
-	r = 1;
-end:
-	sqlite3_finalize(stmt);
-	return r;
-}
-
-/* Write a file to a BLOB in ``chunks`` at row ``rowid``.
- *
- * Returns 0 on failure and 1 on success.
- */
-static int write_chunk(TCHAR *name, HANDLE f, sqlite_int64 rowid)
-{
-	sqlite3_blob *blob;
-	char buf[4096];
-	DWORD read = 0;
-	int has_written = 0;
-	int r = 0;
-
-	if (sqlite3_blob_open(g_db, "main", "chunks", "data", rowid, 1,
-	                      &blob) != SQLITE_OK) {
-		_tprintf("Could not open BLOB to write chunk for %s: %s\n",
-		         name, sqlite3_errmsg_U(g_db));
-		return 0;
-	}
-
-	for (;;) {
-		if (ReadFile(f, buf, sizeof(buf), &read, NULL) == FALSE) {
-			_tprintf("failed to read in %s for sha256 calculation\n",
-			         name);
-			goto end;
-		}
-
-		if (read == 0)
-			break;
-		if (sqlite3_blob_write(g_db, buf, read, has_written)
-		    != SQLITE_OK) {
-			_tprintf("Could not write to BLOB for %s: %s\n",
-			         name, sqlite3_errmsg_U(g_db));
-			goto end;
-		}
-
-		has_written += read;
-	}
-
-	r = 1;
-end:
-	sqlite3_blob_close(blob);
-	return r;
-}
-
-/* Insert a chunk with a specified SHA256 checksum into the database.
- *
- * Returns 1 on success, 0 on failure. On success, ``rowid`` contains
- * the row in ``chunks`` that contains the data of ``f``.
- */
-static int insert_chunk(TCHAR *name, HANDLE f, sqlite_int64 *rowid,
-                        uint8_t sha256[SHASIZ])
-{
-	LARGE_INTEGER fsize = 0;
-	sqlite3_stmt *stmt;
-	int r = 0;
-
-	if (SetFilePointer(f, 0, NULL, FILE_BEGIN)
-	    == INVALID_SET_FILE_POINTER) {
-		_tprintf("rewind for %s failed\n", name);
-		return 0;
-	}
-
-	if (GetFileSizeEx(f, &fsize) == 0) {
-		_tprintf("Could not get the file size of %s\n", name);
-		return 0;
-	}
-
-	/* Chunks are fixed size in SQLite. They need to be pre-allocated
-	 * with the size of a file before a file can be written to it.
-	 */
-	if (sqlite3_prepare(g_db,
-	                    "INSERT INTO chunks (sha256, data) VALUES (hex(?), zeroblob(?)) RETURNING rowid;",
-	                    -1, stmt, NULL) != SQLITE_OK) {
-		_tprintf("Could not prepare chunk insertion for %s: %s\n",
-		         name, sqlite3_errmsg_U(g_db));
-		return 0;
-	}
-
-	if (sqlite3_bind_blob(stmt, 1, sha256, SHASIZ, SQLITE_TRANSIENT)
-	    != SQLITE_OK) {
-		_tprintf("Could not bind sha256 to statement for %s: %s\n",
-		         name, sqlite3_errmsg_U(g_db));
-		goto finalize;
-	}
-
-	if (sqlite3_bind_int64(stmt, 2, fsize) != SQLITE_OK) {
-		_tprintf("Could not bind file size to statement for %s: %s\n",
-		         name, sqlite3_errmsg_U(g_db));
-		goto finalize;
-	}
-
-	if (sqlite3_step(&stmt) != SQLITE_ROW)
-		_tprintf("Could not step chunk insertion statement for %s: %s\n",
-		         name, sqlite3_errmsg_U(g_db));
-		goto finalize;
-	}
-
-	*rowid = sqlite3_column_int64(stmt, 0);
-	r = write_chunk(name, f, *rowid);
-finalize:
-	sqlite3_finalize(stmt);
-	return r;
-}
-
-/* Check if the SHA256 checksum already exists in the database.
- *
- * If the checksum exists, ``rowid`` is filled with the row in ``chunks``
- * that contains that sha256 sum. If it does not exist, then ``rowid``
- * contains ``-1``.
- *
- * Returns 0 if an error occured, and 1 if no error occured.
- */
-static int check_sha256(TCHAR *name, uint8_t sha256[SHASIZ],
-                        sqlite_int64 *rowid)
-{
-	sqlite3_stmt *stmt;
-	int r = 0;
-
-	/* Since ``sha256`` is binary, use ``hex`` to convert the binary
-	 * string to a text representation.
-	 */
-	if (sqlite3_prepare_v2(g_db,
-	                       "SELECT rowid FROM chunks WHERE sha256 = hex(?);",
-	                       -1, &stmt, NULL) != SQLITE_OK) {
-		_tprintf("failed to prepare sha256 statement for %s: %s\n",
-		         name, sqlite_errmsg_U(g_db));
-		goto end;
-	}
-
-	if (sqlite3_bind_blob(&stmt, 1, sha256, SHASIZ, SQLITE_TRANSIENT)
-	    != SQLITE_OK) {
-		_tprintf("failed to bind sha256 value for %s: %s\n",
-		         name, sqlite_errmsg_U(g_db));
-		goto end;
-	}
-
-	switch (sqlite3_step(&stmt)) {
-	case SQLITE_ROW:
-		/* there is a sha256 value */
-		*rowid = sqlite3_column_int(stmt, 0);
-		break;
-	case SQLITE_DONE:
-		/* The chunk was never entered */
-		*rowid = -1;
-		break;
-	}
-
-	r = 1;
-end:
-	sqlite3_finalize(stmt);
-	return r;
-}
-
-/* Calculate the SHA256 checksum of the file in ``f``, and place a binary
- * representation of the checksum into ``shastr``.
- *
- * Returns 0 if there was an error, 1 for success.
- */
-static int calculate_sha256(TCHAR *name, HANDLE f, uint8_t sha256[SHASIZ])
-{
-	DWORD read = 0;
-	uint8_t buf[SIZE_OF_SHA_256_CHUNK * 64];
-	struct Sha_256 sha_state;
-	int i;
-
-	sha_256_init(&sha_state, sha256);
-	for (;;) {
-		if (ReadFile(f, buf, sizeof(buf), &read, NULL) == FALSE) {
-			_tprintf("failed to read in %s for sha256 calculation\n",
-			         name);
-			return 0;
-		}
-
-		/* ReadFile() reads 0 bytes on EOF. */
-		if (read == 0)
-			break;
-		sha_256_write(&sha_state, buf, read);
-	}
-
-	sha_256_close(&sha_state);
-	return 1;
-}
-
-/* Archive a file. */
-static void archive_file(TCHAR *name)
-{
-	HANDLE f;
-	sqlite_int64 chunks_rowid = -1;
-	uint8_t sha256[SHASIZ];
-	char *errstr;
-	int success = 0;
-
-	if (sqlite3_exec(g_db, "SAVEPOINT file;", NULL, NULL, &errstr)
-	    != SQLITE_OK)
-		die("failed to initialize file savepoint: %s\n", errstr);
-
-	f = CreateFile(name, GENERIC_READ, FILE_SHARE_READ, NULL,
-	                     OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
-	if (f == INVALID_HANDLE_VALUE) {
-		_tprintf("could not open %s\n", name);
-		goto end;
-	}
-
-	if (!calculate_sha256(name, f, sha256))
-		goto end;
-	if (!check_sha256(sha256, &chunks_rowid))
-		goto end;
-
-	if (chunks_rowid < 0) {
-		if (!insert_chunk(name, f, &chunks_rowid, sha256))
-			goto end;
-	}
-
-	if (!insert_backup_record(name, chunks_rowid))
-		goto end;
-	success = 1;
-
-	log("Archived %s\n", name);
-end:
-	if (sqlite3_exec(g_db, success ? "RELEASE file;" : "ROLLBACK TO file;", NULL, NULL,
-	                 &errstr) != SQLITE_OK)
-		die("failed to rollback file savepoint: %s\n", errstr);
-	CloseHandle(f);
-}
-
-/* Recursively archive a directory. */
-static void archive_directory(TCHAR *dirname)
-{
-	WIN32_FIND_DATA fdata;
-	HANDLE dhandle;
-	TCHAR pathname[PATH_MAX];
-	dhandle = FindFirstFile(dirname, &fdata);
-	if (dhandle == INVALID_HANDLE_VALUE) {
-		_tprintf("Failed to open directory %s\n", dirname);
-		return;
-	}
-
-	do {
-		/* Windows versions prior to 11 (!) include _snprintf() as
-		 * a non-standard version of snprintf(). _snprintf() will
-		 * return -1 if the string does not fit in the buffer.
-		 */
-		if (_sntprintf(pathname, PATH_MAX, "%s\\%s", dirname,
-		               fdata.cFileName) < 0) {
-			_tprintf("Pathname for %s\\%s too long\n", dirname,
-			         fdata.cFileName);
-			continue;
-		}
-
-		if (fdata.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY)
-			archive_directory(pathname);
-		else
-			archive_file(pathname);
-	} while (FindNextFile(dhandle, &fdata) != 0);
-
-	FindClose(dhandle);
-}
-
-/* Check if the path is a file or a directory, and either archive
- * the file or archive the entire directory recursively. */
-static void archive_file_or_directory(TCHAR *name)
-{
-	DWORD attr = GetFileAttributes(fn);
-	if (attr == INVALID_FILE_ATTRIBUTES) {
-		_tprintf(TEXT("failed to open %s\n"), name);
-		return;
-	}
-
-	if (g_backup_id < 0)
-		initialize_backup_id();
-
-	if (attr & FILE_ATTRIBUTE_DIRECTORY)
-		archive_directory(name);
-	else
-		archive_file(name);
-}
-
-/* Print instructions to console and exit. */
-static void usage(void)
-{
-	_tprintf(TEXT("\nwlb [\\V] [\\H] [\\D DBNAME] [\\A DIRECTORIES...]\n"));
-	_tprintf(TEXT("\\V: Verbose\n"));
-	_tprintf(TEXT("\\H: Display the help\n"));
-	_tprintf(TEXT("\\D: Database (create if does not exist)\n"));
-	_tprintf(TEXT("\\A: Archive directories\n"));
-	exit(0);
-}
-
-int _tmain(int argc, TCHAR *argv[])
-{
-	int i;
-
-	for (i = 1; i < argc; i++) {
-		if (_tcscmp(argv[i], TEXT("\\H")) == 0) {
-			usage();
-		} else if (_tcscmp(argv[i], TEXT("\\A")) == 0) {
-			i++;
-			archive_file_or_directory(argv[i]);
-		} else if (_tcscmp(argv[i], TEXT("\\D")) == 0) {
-			i++;
-			open_db(argv[i]);
-		} else if (_tcscmp(argv[i], TEXT("\\V")) == 0) {
-			g_verbose = 1;
-		} else {
-			usage();
-		}
-	}
-
-	if (g_db)
-		sqlite3_exec(g_db, "COMMIT;", NULL, NULL, NULL);
-	sqlite3_close(g_db);
+#include <windows.h>

+#include <stdlib.h>

+#include <tchar.h>

+#include <winapi/winbase.h> /* Contains GetFileSizeEx */

+#ifndef UNICODE

+# include <stdio.h>

+#else

+# include <wchar.h>

+#endif

+#include "sqlite3.h"

+#include "sha-256.h"

+#define SHASIZ SIZE_OF_SHA_256_HASH

+

+/* TODO: "\\?\" trick?

+ * Windows limits path lengths to 260 characters. Explorer on Windows XP

+ * has this issue too.

+ *

+ * UTF issues?

+ */

+

+/*************************************************************************

+ *  Compatability defines for non-Unicode systems

+ ************************************************************************/

+

+#ifdef UNICODE

+# define ENCODING SQLITE3_UTF16

+# define sqlite3_open_U sqlite3_open16

+# define sqlite3_errmsg_U sqlite3_errmsg16

+# define sqlite3_bind_text_U sqlite3_bind_text16

+#else

+# define ENCODING SQLITE3_UTF8

+# define sqlite3_open_U sqlite3_open

+# define sqlite3_errmsg_U sqlite3_errmsg

+# define sqlite3_bind_text_U sqlite3_bind_text

+#endif

+

+/****************

+ * Globals

+ ***************/

+

+sqlite3 *g_db = NULL;

+int g_verbose = 0;

+sqlite_int64 g_backup_id = -1;

+

+/********************

+ * Utility Functions

+ *******************/

+

+static void _log(TCHAR *msg, ...)

+{

+	va_list va;

+

+	if (g_verbose) {

+		va_start(va, msg);

+		_vtprintf(msg, va);

+		va_end(va);

+	}

+}

+/* String literals only */

+#define log(msg, ...) _log(TEXT(msg), __VA_ARGS__)

+

+static void _die(TCHAR *emsg, ...)

+{

+	va_list va;

+	va_start(va, emsg);

+	_vtprintf(emsg, va);

+	va_end(va);

+

+	sqlite3_close(g_db);

+	exit(1);

+}

+/* String literals only */

+#define die(emsg, ...) _die(TEXT(emsg), __VA_ARGS__)

+

+/**********************************

+ * Database constants

+ *********************************/

+

+/* 'wlb' in ASCII */

+#define UPPER_VERSION 0x776c62

+#define CUR_VERSION 0x776c6201

+#define S(s) #s

+#define INIT_SCRIPT "\

+BEGIN; \

+PRAGMA user_version = " S(CUR_VERSION) ";\

+CREATE TABLE chunks (\

+	rowid INTEGER PRIMARY KEY, \

+	sha256 TEXT UNIQUE NOT NULL, \

+	data BLOB NOT NULL\

+); \

+CREATE TABLE backup_ids (\

+	ts TEXT UNIQUE NOT NULL,\

+	rowid INTEGER PRIMARY KEY\

+); \

+CREATE TABLE backups (\

+	backup INTEGER NOT NULL REFERENCES backup_ids ON DELETE CASCADE, \

+	path TEXT NOT NULL, \

+	chunk INTEGER NOT NULL REFERENCES chunks ON DELETE RESTRICT\

+); \

+CREATE INDEX backups_paths ON backups (path); \

+CREATE INDEX backups_backup ON backups (backup); \

+CREATE INDEX backups_chunk ON backups (chunk);\

+COMMIT;"

+

+/* Check if the database version is correct. If it is not correct

+ * and the create flag is enabled, then initialize a new database.

+ */

+static void check_db_version(int did_not_exist)

+{

+	int user_version;

+	sqlite3_stmt *stmt;

+

+	/* DB did not exist beforehand: initialize DB */

+	if (did_not_exist) {

+		if (sqlite3_exec(g_db, INIT_SCRIPT, NULL, NULL, NULL) != SQLITE_OK)

+			die("Error initializing database: %s\n",

+			    sqlite3_errmsg_U(g_db));

+		log("%s", "Intialized database\n");

+		return;

+	}

+

+	/* DB existed beforehand: do version check */

+	if (sqlite3_prepare_v2(g_db, "PRAGMA user_version;", -1, &stmt, NULL)

+	                       != SQLITE_OK)

+		die("Error preparing user version check: %s\n",

+		    sqlite3_errmsg_U(g_db));

+	if (sqlite3_step(stmt) != SQLITE_ROW)

+		die("Error executing user version check: %s\n",

+		    sqlite3_errmsg_U(g_db));

+	user_version = sqlite3_column_int(stmt, 0);

+	sqlite3_finalize(stmt);

+

+	if (user_version != CUR_VERSION) {

+		die("Bad DB version found (expected %d), got %d\n",

+		    CUR_VERSION & 0xFF, user_version & 0xFF);

+	}

+}

+

+/* Initialize the backup ID used in this session.

+ * This is only called if the user requests an archive of a directory.

+ */

+static void initialize_backup_id(void)

+{

+	sqlite3_stmt *stmt;

+

+	if (sqlite3_prepare(g_db,

+	                    "INSERT INTO backup_ids (ts) VALUES (datetime()) RETURNING rowid;",

+	                    -1, &stmt, NULL) != SQLITE_OK) {

+		die("failed to prepare inserting timestamp: %s\n",

+		    sqlite3_errmsg_U(g_db));

+	}

+

+	if (sqlite3_step(stmt) != SQLITE_ROW)

+		die("failed to insert timestamp: %s\n",

+		    sqlite3_errmsg_U(g_db));

+	g_backup_id = sqlite3_column_int64(stmt, 0);

+	sqlite3_finalize(stmt);

+}

+

+/* Opens the DB and initializes it if it did not exist. */

+static void open_db(TCHAR *fn)

+{

+	int did_not_exist = GetFileAttributes(fn)

+	                    == INVALID_FILE_ATTRIBUTES;

+	char *errmsg;

+

+	if (sqlite3_open_U(fn, &g_db) != SQLITE_OK)

+		die("Error opening database %s: %s\n", fn,

+		    sqlite3_errmsg_U(g_db));

+	check_db_version(did_not_exist);

+

+	/* Store current timestamp */

+	if (sqlite3_exec(g_db, "BEGIN;", NULL, NULL, &errmsg) != SQLITE_OK)

+		die("failed to begin transaction: %s\n", errmsg);

+}

+

+/* Insert a backup record into the database.

+ *

+ * This part occurs after the file data has been inserted or identified

+ * by SHA256 hash.

+ */

+static int insert_backup_record(TCHAR *name, sqlite_int64 chunk_id)

+{

+	sqlite3_stmt *stmt;

+	int r = 0;

+

+	if (sqlite3_prepare(g_db,

+	                    "INSERT INTO backups (backup, path, chunk) VALUES (?,?,?);",

+	                    -1, &stmt, NULL) != SQLITE_OK) {

+		_tprintf("Could not prepare backup insert statement for %s: %s\n",

+		         name, sqlite3_errmsg_U(g_db));

+		return 0;

+	}

+

+	if (sqlite3_bind_int64(stmt, 1, g_backup_id) != SQLITE_OK) {

+		_tprintf("Could not bind backup id for %s: %s\n", name,

+		         sqlite3_errmsg_U(g_db));

+		goto end;

+	}

+

+	if (sqlite3_bind_text_U(stmt, 2, name, -1, SQLITE_TRANSIENT) != SQLITE_OK) {

+		_tprintf("Could not bind path for %s: %s\n", name,

+		         sqlite3_errmsg_U(g_db));

+		goto end;

+	}

+

+	if (sqlite3_bind_int64(stmt, 3, chunk_id) != SQLITE_OK) {

+		_tprintf("Could not bind chunk for %s: %s\n", name,

+		         sqlite3_errmsg_U(g_db));

+		goto end;

+	}

+

+	if (sqlite3_step(stmt) != SQLITE_DONE) {

+		_tprintf("Error in inserting chunk for %s: %s\n", name,

+		         sqlite3_errmsg_U(g_db));

+		goto end;

+	}

+

+	r = 1;

+end:

+	sqlite3_finalize(stmt);

+	return r;

+}

+

+/* Write a file to a BLOB in ``chunks`` at row ``rowid``.

+ *

+ * Returns 0 on failure and 1 on success.

+ */

+static int write_chunk(TCHAR *name, HANDLE f, sqlite_int64 rowid)

+{

+	sqlite3_blob *blob;

+	char buf[4096];

+	DWORD read = 0;

+	int has_written = 0;

+	int r = 0;

+

+	if (sqlite3_blob_open(g_db, "main", "chunks", "data", rowid, 1,

+	                      &blob) != SQLITE_OK) {

+		_tprintf("Could not open BLOB to write chunk for %s: %s\n",

+		         name, sqlite3_errmsg_U(g_db));

+		return 0;

+	}

+

+	for (;;) {

+		if (ReadFile(f, buf, sizeof(buf), &read, NULL) == FALSE) {

+			_tprintf("failed to read in %s for sha256 calculation\n",

+			         name);

+			goto end;

+		}

+

+		if (read == 0)

+			break;

+		if (sqlite3_blob_write(g_db, buf, read, has_written)

+		    != SQLITE_OK) {

+			_tprintf("Could not write to BLOB for %s: %s\n",

+			         name, sqlite3_errmsg_U(g_db));

+			goto end;

+		}

+

+		has_written += read;

+	}

+

+	r = 1;

+end:

+	sqlite3_blob_close(blob);

+	return r;

+}

+

+/* Insert a chunk with a specified SHA256 checksum into the database.

+ *

+ * Returns 1 on success, 0 on failure. On success, ``rowid`` contains

+ * the row in ``chunks`` that contains the data of ``f``.

+ */

+static int insert_chunk(TCHAR *name, HANDLE f, sqlite_int64 *rowid,

+                        uint8_t sha256[SHASIZ])

+{

+	/* NOTE: Windows XP x86 does not support GetFilesizeEx() */

+	DWORD fsizeLow, fsizeHigh;

+	sqlite3_int64 fsize;

+	sqlite3_stmt *stmt;

+	int r = 0;

+

+	if (SetFilePointer(f, 0, NULL, FILE_BEGIN)

+	    == INVALID_SET_FILE_POINTER) {

+		_tprintf("rewind for %s failed\n", name);

+		return 0;

+	}

+

+	fsizeLow = GetFileSize(f, &fsizeHigh);

+	if (fsizeLow == INVALID_FILE_SIZE) {

+		_tprintf("Could not get the file size of %s\n", name);

+		return 0;

+	}

+	fsize = fsizeLow | (fsizeHigh << 32);

+

+	/* Chunks are fixed size in SQLite. They need to be pre-allocated

+	 * with the size of a file before a file can be written to it.

+	 */

+	if (sqlite3_prepare(g_db,

+	                    "INSERT INTO chunks (sha256, data) VALUES (hex(?), zeroblob(?)) RETURNING rowid;",

+	                    -1, &stmt, NULL) != SQLITE_OK) {

+		_tprintf("Could not prepare chunk insertion for %s: %s\n",

+		         name, sqlite3_errmsg_U(g_db));

+		return 0;

+	}

+

+	if (sqlite3_bind_blob(stmt, 1, sha256, SHASIZ, SQLITE_TRANSIENT)

+	    != SQLITE_OK) {

+		_tprintf("Could not bind sha256 to statement for %s: %s\n",

+		         name, sqlite3_errmsg_U(g_db));

+		goto finalize;

+	}

+

+	if (sqlite3_bind_int64(stmt, 2, fsize) != SQLITE_OK) {

+		_tprintf("Could not bind file size to statement for %s: %s\n",

+		         name, sqlite3_errmsg_U(g_db));

+		goto finalize;

+	}

+

+	if (sqlite3_step(stmt) != SQLITE_ROW) {

+		_tprintf("Could not step chunk insertion statement for %s: %s\n",

+		         name, sqlite3_errmsg_U(g_db));

+		goto finalize;

+	}

+

+	*rowid = sqlite3_column_int64(stmt, 0);

+	r = write_chunk(name, f, *rowid);

+finalize:

+	sqlite3_finalize(stmt);

+	return r;

+}

+

+/* Check if the SHA256 checksum already exists in the database.

+ *

+ * If the checksum exists, ``rowid`` is filled with the row in ``chunks``

+ * that contains that sha256 sum. If it does not exist, then ``rowid``

+ * contains ``-1``.

+ *

+ * Returns 0 if an error occured, and 1 if no error occured.

+ */

+static int check_sha256(TCHAR *name, uint8_t sha256[SHASIZ],

+                        sqlite_int64 *rowid)

+{

+	sqlite3_stmt *stmt;

+	int r = 0;

+

+	/* Since ``sha256`` is binary, use ``hex`` to convert the binary

+	 * string to a text representation.

+	 */

+	if (sqlite3_prepare_v2(g_db,

+	                       "SELECT rowid FROM chunks WHERE sha256 = hex(?);",

+	                       -1, &stmt, NULL) != SQLITE_OK) {

+		_tprintf("failed to prepare sha256 statement for %s: %s\n",

+		         name, sqlite3_errmsg_U(g_db));

+		goto end;

+	}

+

+	if (sqlite3_bind_blob(stmt, 1, sha256, SHASIZ, SQLITE_TRANSIENT)

+	    != SQLITE_OK) {

+		_tprintf("failed to bind sha256 value for %s: %s\n",

+		         name, sqlite3_errmsg_U(g_db));

+		goto end;

+	}

+

+	switch (sqlite3_step(stmt)) {

+	case SQLITE_ROW:

+		/* there is a sha256 value */

+		*rowid = sqlite3_column_int(stmt, 0);

+		break;

+	case SQLITE_DONE:

+		/* The chunk was never entered */

+		*rowid = -1;

+		break;

+	}

+

+	r = 1;

+end:

+	sqlite3_finalize(stmt);

+	return r;

+}

+

+/* Calculate the SHA256 checksum of the file in ``f``, and place a binary

+ * representation of the checksum into ``shastr``.

+ *

+ * Returns 0 if there was an error, 1 for success.

+ */

+static int calculate_sha256(TCHAR *name, HANDLE f, uint8_t sha256[SHASIZ])

+{

+	DWORD read = 0;

+	uint8_t buf[SIZE_OF_SHA_256_CHUNK * 64];

+	struct Sha_256 sha_state;

+	int i;

+

+	sha_256_init(&sha_state, sha256);

+	for (;;) {

+		if (ReadFile(f, buf, sizeof(buf), &read, NULL) == FALSE) {

+			_tprintf("failed to read in %s for sha256 calculation\n",

+			         name);

+			return 0;

+		}

+

+		/* ReadFile() reads 0 bytes on EOF. */

+		if (read == 0)

+			break;

+		sha_256_write(&sha_state, buf, read);

+	}

+

+	sha_256_close(&sha_state);

+	return 1;

+}

+

+/* Archive a file. */

+static void archive_file(TCHAR *name)

+{

+	HANDLE f;

+	sqlite_int64 chunks_rowid = -1;

+	uint8_t sha256[SHASIZ];

+	char *errstr;

+	int success = 0;

+

+	if (sqlite3_exec(g_db, "SAVEPOINT file;", NULL, NULL, &errstr)

+	    != SQLITE_OK)

+		die("failed to initialize file savepoint: %s\n", errstr);

+

+	f = CreateFile(name, GENERIC_READ, FILE_SHARE_READ, NULL,

+	                     OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);

+	if (f == INVALID_HANDLE_VALUE) {

+		_tprintf("could not open %s\n", name);

+		goto end;

+	}

+

+	if (!calculate_sha256(name, f, sha256))

+		goto end;

+	if (!check_sha256(name, sha256, &chunks_rowid))

+		goto end;

+

+	if (chunks_rowid < 0) {

+		if (!insert_chunk(name, f, &chunks_rowid, sha256))

+			goto end;

+	}

+

+	if (!insert_backup_record(name, chunks_rowid))

+		goto end;

+	success = 1;

+

+	log("Archived %s\n", name);

+end:

+	if (sqlite3_exec(g_db, success ? "RELEASE file;" : "ROLLBACK TO file;", NULL, NULL,

+	                 &errstr) != SQLITE_OK)

+		die("failed to rollback file savepoint: %s\n", errstr);

+	CloseHandle(f);

+}

+

+/* Recursively archive a directory. */

+static void archive_directory(TCHAR *dirname)

+{

+	WIN32_FIND_DATA fdata;

+	HANDLE dhandle;

+	TCHAR pathname[PATH_MAX];

+	dhandle = FindFirstFile(dirname, &fdata);

+	if (dhandle == INVALID_HANDLE_VALUE) {

+		_tprintf("Failed to open directory %s\n", dirname);

+		return;

+	}

+

+	do {

+		/* Windows versions prior to 11 (!) include _snprintf() as

+		 * a non-standard version of snprintf(). _snprintf() will

+		 * return -1 if the string does not fit in the buffer.

+		 */

+		if (_sntprintf(pathname, PATH_MAX, "%s\\%s", dirname,

+		               fdata.cFileName) < 0) {

+			_tprintf("Pathname for %s\\%s too long\n", dirname,

+			         fdata.cFileName);

+			continue;

+		}

+

+		if (fdata.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY)

+			archive_directory(pathname);

+		else

+			archive_file(pathname);

+	} while (FindNextFile(dhandle, &fdata) != 0);

+

+	FindClose(dhandle);

+}

+

+/* Check if the path is a file or a directory, and either archive

+ * the file or archive the entire directory recursively. */

+static void archive_file_or_directory(TCHAR *name)

+{

+	DWORD attr = GetFileAttributes(name);

+	if (attr == INVALID_FILE_ATTRIBUTES) {

+		_tprintf(TEXT("failed to open %s\n"), name);

+		return;

+	}

+

+	if (g_backup_id < 0)

+		initialize_backup_id();

+

+	if (attr & FILE_ATTRIBUTE_DIRECTORY)

+		archive_directory(name);

+	else

+		archive_file(name);

+}

+

+/* Print instructions to console and exit. */

+static void usage(void)

+{

+	_tprintf(TEXT("\nwlb [\\V] [\\H] [\\D DBNAME] [\\A DIRECTORIES...]\n"));

+	_tprintf(TEXT("\\V: Verbose\n"));

+	_tprintf(TEXT("\\H: Display the help\n"));

+	_tprintf(TEXT("\\D: Database (create if does not exist)\n"));

+	_tprintf(TEXT("\\A: Archive directories\n"));

+	exit(0);

+}

+

+int _tmain(int argc, TCHAR *argv[])

+{

+	int i;

+

+	for (i = 1; i < argc; i++) {

+		if (_tcscmp(argv[i], TEXT("\\H")) == 0) {

+			usage();

+		} else if (_tcscmp(argv[i], TEXT("\\A")) == 0) {

+			i++;

+			archive_file_or_directory(argv[i]);

+		} else if (_tcscmp(argv[i], TEXT("\\D")) == 0) {

+			i++;

+			open_db(argv[i]);

+		} else if (_tcscmp(argv[i], TEXT("\\V")) == 0) {

+			g_verbose = 1;

+		} else {

+			usage();

+		}

+	}

+

+	if (g_db)

+		sqlite3_exec(g_db, "COMMIT;", NULL, NULL, NULL);

+	sqlite3_close(g_db);

 	return 0;
 }