replace substitute_newlines() object typecheck with object field

This is the more generic way, although I doubt this is really error
preventing. To me, it's not totally clear as to when
substitute_newlines() is forbidden and when not. Maybe someone (the
author?) can shed light on the internal algorithm of this feature.

src/conky.c

@@ -805,13 +805,8 @@ obj_loop_tail:
 #ifdef HAVE_ICONV
 			iconv_convert(&a, buff_in, p, p_max_size);
 #endif /* HAVE_ICONV */
-			if (obj->type != OBJ_text && obj->type != OBJ_execp && obj->type != OBJ_execpi
+			if (!obj->verbatim_output)
-#ifdef HAVE_LUA
-					&& obj->type != OBJ_lua && obj->type != OBJ_lua_parse
-#endif /* HAVE_LUA */
-					) {
 				substitute_newlines(p, a - 2);
-			}
 			p += a;
 			p_max_size -= a;
 			(*p) = 0;

src/core.c

@@ -563,6 +563,7 @@ struct text_object *construct_text_object(const char *s, const char *arg, long
 		obj->callbacks.free = &free_exec;
 	END OBJ(execp, 0)
 		scan_exec_arg(obj, arg);
+		obj->verbatim_output = 1;
 		obj->callbacks.print = &print_execp;
 		obj->callbacks.free = &free_exec;
 	END OBJ(execbar, 0)
@@ -599,6 +600,7 @@ struct text_object *construct_text_object(const char *s, const char *arg, long
 		obj->callbacks.free = &free_execi;
 	END OBJ_ARG(execpi, 0, "execpi needs arguments")
 		scan_execi_arg(obj, arg);
+		obj->verbatim_output = 1;
 		obj->callbacks.print = &print_execpi;
 		obj->callbacks.free = &free_execi;
 	END OBJ_ARG(texeci, 0, "texeci needs arguments")
@@ -1389,10 +1391,12 @@ struct text_object *construct_text_object(const char *s, const char *arg, long
 #ifdef HAVE_LUA
 	END OBJ_ARG(lua, 0, "lua needs arguments: <function name> [function parameters]")
 		obj->data.s = strndup(arg, text_buffer_size);
+		obj->verbatim_output = 1;
 		obj->callbacks.print = &print_lua;
 		obj->callbacks.free = &gen_free_opaque;
 	END OBJ_ARG(lua_parse, 0, "lua_parse needs arguments: <function name> [function parameters]")
 		obj->data.s = strndup(arg, text_buffer_size);
+		obj->verbatim_output = 1;
 		obj->callbacks.print = &print_lua_parse;
 		obj->callbacks.free = &gen_free_opaque;
 	END OBJ_ARG(lua_bar, 0, "lua_bar needs arguments: <height>,<width> <function name> [function parameters]")

src/text_object.c

@@ -26,10 +26,12 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  *
  */
+#define _GNU_SOURCE
 #include "text_object.h"
 #include "logging.h"
 #include <stdlib.h>
 #include <stdio.h>
+#include <string.h>
 
 void gen_free_opaque(struct text_object *obj)
 {
@@ -196,6 +198,7 @@ void obj_be_plain_text(struct text_object *obj, const char *text)
 {
 	obj->type = OBJ_text;
 	obj->data.s = strdup(text);
+	obj->verbatim_output = 1;
 
 	memset(&obj->callbacks, 0, sizeof(obj->callbacks));
 	obj->callbacks.print = &gen_print_obj_data_s;

src/text_object.h

@@ -516,6 +516,9 @@ struct text_object {
 		long l;			/* some long integer */
 	} data;
 
+	/* if non-zero, no substitute_newlines() is applied to object's output */
+	char verbatim_output;
+
 	void *special_data;
 	int type;
 	long line;