say: Don't prepend ampersand erroneously.

Some logic in say.c for determining if we need
to also add an ampersand for file seperation was faulty,
as non-successful files would increment the count, causing
a leading ampersand to be added improperly.

This is fixed, and a unit test that captures this regression
is also added.

ASTERISK-30248 #close

Change-Id: I02c1d3a11d82fe4ea8b462070cbd1effb5834d2b

funcs/func_sayfiles.c

@@ -211,6 +211,15 @@ AST_TEST_DEFINE(test_SAYFILES_function)
 		res = AST_TEST_FAIL;
 	}
 
+	/* + should be ignored and there should not be a leading & */
+	ast_str_set(&expr, 0, "${SAYFILES(+18005551212,digits)}");
+	ast_str_substitute_variables(&result, 0, NULL, ast_str_buffer(expr));
+	if (strcmp(ast_str_buffer(result), "digits/1&digits/8&digits/0&digits/0&digits/5&digits/5&digits/5&digits/1&digits/2&digits/1&digits/2") != 0) {
+		ast_test_status_update(test, "SAYFILES(+18005551212,digits) test failed ('%s')\n",
+				ast_str_buffer(result));
+		res = AST_TEST_FAIL;
+	}
+
 	ast_str_set(&expr, 0, "${SAYFILES(35,number)}");
 	ast_str_substitute_variables(&result, 0, NULL, ast_str_buffer(expr));
 	if (strcmp(ast_str_buffer(result), "digits/30&digits/5") != 0) {

main/say.c

@@ -160,7 +160,7 @@ struct ast_str* ast_get_character_str(const char *str, const char *lang, enum as
 		}
 		if ((fn && ast_fileexists(fn, NULL, lang) > 0) ||
 			(snprintf(asciibuf + 13, sizeof(asciibuf) - 13, "%d", str[num]) > 0 && ast_fileexists(asciibuf, NULL, lang) > 0 && (fn = asciibuf))) {
-			ast_str_append(&filenames, 0, (num == 0 ? "%s" : "&%s"), fn);
+			ast_str_append(&filenames, 0, "%s%s", ast_str_strlen(filenames) ? "&" : "", fn);
 		}
 		if (upper || lower) {
 			continue;
@@ -282,7 +282,7 @@ struct ast_str* ast_get_phonetic_str(const char *str, const char *lang)
 			fn = fnbuf;
 		}
 		if (fn && ast_fileexists(fn, NULL, lang) > 0) {
-			ast_str_append(&filenames, 0, (num == 0 ? "%s" : "&%s"), fn);
+			ast_str_append(&filenames, 0, "%s%s", ast_str_strlen(filenames) ? "&" : "", fn);
 		}
 		num++;
 	}
@@ -336,7 +336,7 @@ struct ast_str* ast_get_digit_str(const char *str, const char *lang)
 			break;
 		}
 		if (fn && ast_fileexists(fn, NULL, lang) > 0) {
-			ast_str_append(&filenames, 0, (num == 0 ? "%s" : "&%s"), fn);
+			ast_str_append(&filenames, 0, "%s%s", ast_str_strlen(filenames) ? "&" : "", fn);
 		}
 		num++;
 	}