Allow the path to file to include symlinks

Symlinks are not followed below the root, to avoid potential recursions

Windows is an exception, since we don't have an 'lstat' equivalent

extract-xiso.c

@@ -352,6 +352,7 @@
 		#define lseek					_lseeki64
 		#define mkdir(a, b)				_mkdir(a)
 		#define stat					_stat64
+		#define lstat					_stat64
 		#define realpath(a, b)			_fullpath(b, a, _MAX_PATH)
 
 		#define bswap_16(x)				_byteswap_ushort(x)
@@ -986,35 +987,39 @@ int create_xiso( char *in_root_directory, const char *in_output_directory, dir_n
 	write_tree_context		wt_context = { 0 };
 	uint32_t				start_sector = 0;
 	int						i = 0, n = 0, xiso = -1, err = 0;
-	char				   *cwd = NULL, *iso_name = NULL, *xiso_path = NULL, *iso_dir = NULL, *real_path = NULL;
+	char				   *cwd = NULL, *iso_name = NULL, *xiso_path = NULL, *iso_dir = NULL, *real_path = NULL, *in_dir_path = NULL;
 
 	s_total_bytes = s_total_files = 0;
 
 	if ( ( cwd = getcwd( NULL, 0 ) ) == NULL ) mem_err();
-	if ( ! err ) {
-		if ( ! in_root ) {
-			i = (int)strlen(in_root_directory) - 1;
-			if ( in_root_directory[i] == '/' || in_root_directory[i] == '\\' ) in_root_directory[i] = 0;
-			if ((iso_dir = strrchr(in_root_directory, PATH_CHAR))) iso_dir++;
-			else iso_dir = in_root_directory;
-
-			iso_name = in_name ? in_name : iso_dir;
-		} else {
+	if (!err) {
+		if (!in_root) {
+			if ((in_dir_path = realpath(in_root_directory, NULL)) == NULL) misc_err("unable to get absolute path of %s: %s", in_root_directory, strerror(errno));
+			if (!err) {
+				// Remember not to free in_dir_path until iso_dir is not needed anymore
+				if ((iso_dir = strrchr(in_dir_path, PATH_CHAR)) != NULL) iso_dir++;
+				else iso_dir = in_dir_path;
+				iso_name = in_name ? in_name : iso_dir;
+			}
+		}
+		else {
 			iso_dir = iso_name = in_root_directory;
 		}
 	}
-	if ( ! err ) {
-		if ( ! *iso_dir ) iso_dir = PATH_CHAR_STR;
-		if ( ! iso_name || ! *iso_name ) iso_name = "root";
-		else if ( iso_name[ 1 ] == ':' ) { iso_name[ 1 ] = iso_name[ 0 ]; ++iso_name; }
-		if (!err && (real_path = realpath(in_output_directory ? in_output_directory : ".", NULL)) == NULL) misc_err("unable to get absolute path of %s: %s", real_path, strerror(errno));
+	if(!err) {
+		if (!iso_dir || !*iso_dir) iso_dir = PATH_CHAR_STR;
+		if (!iso_name || !*iso_name) iso_name = "root";
+		else if (iso_name[1] == ':') { iso_name[1] = iso_name[0]; ++iso_name; }
+
+		if (in_output_directory == NULL) in_output_directory = ".";
+		if (!err && (real_path = realpath(in_output_directory, NULL)) == NULL) misc_err("unable to get absolute path of %s: %s", in_output_directory, strerror(errno));
 		if (!err && (asprintf(&xiso_path, "%s%c%s%s", real_path, PATH_CHAR, iso_name, in_name ? "" : ".iso")) == -1) mem_err();
 		if (real_path) {
 			free(real_path);
 			real_path = NULL;
 		}
 
-		if (!err && !in_root && chdir(in_root_directory) == -1) chdir_err(in_root_directory);
+		if (!err && !in_root && chdir(in_dir_path) == -1) chdir_err(in_dir_path);
 	}
 	if ( ! err ) {
 		exiso_log( "\n%s %s%s:\n", in_root ? "rewriting" : "creating", iso_name, in_name ? "" : ".iso" );
@@ -1090,7 +1095,7 @@ int create_xiso( char *in_root_directory, const char *in_output_directory, dir_n
 	if ( ! err && write( xiso, XISO_HEADER_DATA, XISO_HEADER_DATA_LENGTH ) != XISO_HEADER_DATA_LENGTH ) write_err();
 
 	if ( ! err && ! in_root ) {
-		if ( chdir( ".." ) == -1 ) chdir_err( ".." );
+		if (chdir("..") == -1) chdir_err("..");
 	}
 	if (!err && (root.filename = strdup(iso_dir)) == NULL) mem_err();
 	if (!err) {
@@ -1138,6 +1143,11 @@ int create_xiso( char *in_root_directory, const char *in_output_directory, dir_n
 	if (root.filename) free(root.filename);
 	if (root.filename_cp1252) free(root.filename_cp1252);
 
+	if (in_dir_path) {
+		free(in_dir_path);
+		in_dir_path = NULL;
+	}
+
 	if ( cwd ) {
 		if ( chdir( cwd ) == -1 ) chdir_err( cwd );
 		free( cwd );
@@ -2032,7 +2042,7 @@ int generate_avl_tree_local( dir_node_avl **out_root, int *io_n ) {
 				avl->filename = NULL;
 			} else if ((avl->filename_cp1252 = getCP1252String(p->d_name)) == NULL) mem_err();
 		}
-		if ( ! err && stat( p->d_name, &sb ) == -1 ) read_err();
+		if ( ! err && lstat( p->d_name, &sb ) == -1 ) read_err();
 		if ( ! err ) {
 			if ( S_ISDIR( sb.st_mode ) ) {
 				empty_dir = false;