From 007e6ecefb0b43d0b9e7bf85f75ec050b5c520e5 Mon Sep 17 00:00:00 2001 From: Mark Wielaard Date: Sat, 7 Aug 2021 17:32:41 +0200 Subject: [PATCH] lex: accept zero codepoints in strings Zero characters (codepoints) are acceptable in strings. The current Lexer::parse_string skipped such zero codepoints by accidents. The zero codepoint was also used as error/skip indicator, but that is only true if the third argument of utf8_escape_pair is true (yes, it is called pair, but is a triple). Add a testcase that checks the (sub)strings are separated by zero chars. Since we cannot slice strings yet this uses extern "C" functions, printf and memchr. --- gcc/rust/lex/rust-lex.cc | 3 ++- .../rust/execute/torture/str-zero.rs | 26 +++++++++++++++++++ 2 files changed, 28 insertions(+), 1 deletion(-) create mode 100644 gcc/testsuite/rust/execute/torture/str-zero.rs diff --git a/gcc/rust/lex/rust-lex.cc b/gcc/rust/lex/rust-lex.cc index 0b8a8eae651..49b6b6d32a7 100644 --- a/gcc/rust/lex/rust-lex.cc +++ b/gcc/rust/lex/rust-lex.cc @@ -1827,7 +1827,8 @@ Lexer::parse_string (Location loc) else length += std::get<1> (utf8_escape_pair); - if (current_char32 != Codepoint (0)) + if (current_char32 != Codepoint (0) + || !std::get<2> (utf8_escape_pair)) str += current_char32; // required as parsing utf8 escape only changes current_char diff --git a/gcc/testsuite/rust/execute/torture/str-zero.rs b/gcc/testsuite/rust/execute/torture/str-zero.rs new file mode 100644 index 00000000000..e7fba0d1372 --- /dev/null +++ b/gcc/testsuite/rust/execute/torture/str-zero.rs @@ -0,0 +1,26 @@ +/* { dg-output "bar foo baz foobar\n" } */ +extern "C" +{ + fn printf(s: *const i8, ...); + fn memchr(s: *const i8, c: u8, n: usize) -> *const i8; +} + +pub fn main () -> i32 +{ + let f = "%s %s %s %s\n\0"; + let s = "bar\0\ + foo\ + \x00\ + baz\u{0000}\ + foobar\0"; + let cf = f as *const str as *const i8; + let cs = s as *const str as *const i8; + unsafe + { + let cs2 = memchr (cs, b'f', 5); + let cs3 = memchr (cs2, b'b', 5); + let cs4 = memchr (cs3, b'f', 5); + printf (cf, cs, cs2, cs3, cs4); + } + 0 +} -- 2.32.0