diff --git a/libcxx/test/std/input.output/file.streams/fstreams/ifstream.members/offset_range.pass.cpp b/libcxx/test/std/input.output/file.streams/fstreams/ifstream.members/offset_range.pass.cpp new file mode 100644 index 0000000000000..5afd4465db31e --- /dev/null +++ b/libcxx/test/std/input.output/file.streams/fstreams/ifstream.members/offset_range.pass.cpp @@ -0,0 +1,82 @@ +//===----------------------------------------------------------------------===// +// +// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. +// See https://llvm.org/LICENSE.txt for license information. +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception +// +//===----------------------------------------------------------------------===// + +// + +// Test that we can seek using offsets larger than 32 bit, and that we can +// retrieve file offsets larger than 32 bit. + +// On MSVC targets, we only use the 32 bit fseek/ftell functions. For MinGW +// targets, we use fseeko/ftello, but the user needs to define +// _FILE_OFFSET_BITS=64 to make them 64 bit. +// +// XFAIL: target={{.*}}-windows{{.*}} + +// On 32 bit Android platforms, off_t is 32 bit by default. By defining +// _FILE_OFFSET_BITS=64, one gets a 64 bit off_t, but the corresponding +// 64 bit ftello/fseeko functions are only available since Android API 24 (7.0). +// (On 64 bit Android platforms, off_t has always been 64 bit.) +// +// XFAIL: target={{i686|arm.*}}-{{.+}}-android{{.*}} + +// Writing the >4 GB test file fails on 32 bit AIX. +// +// XFAIL: target=powerpc-{{.+}}-aix{{.*}} + +#include +#include +#include +#include + +#include "assert_macros.h" +#include "platform_support.h" +#include "test_macros.h" + +void test_tellg(std::streamoff total_size) { + std::vector data(8192); + for (std::size_t i = 0; i < data.size(); ++i) + data[i] = static_cast(i % (1 << 8 * sizeof(char))); + std::string p = get_temp_file_name(); + { + std::ofstream ofs; + ofs.open(p, std::ios::out | std::ios::binary); + assert(ofs.is_open()); + for (std::streamoff size = 0; size < total_size;) { + std::size_t n = std::min(static_cast(data.size()), total_size - size); + ofs.write(data.data(), n); + size += n; + } + assert(!ofs.fail()); + ofs.close(); + } + { + std::ifstream ifs; + ifs.open(p, std::ios::binary); + assert(ifs.is_open()); + std::streamoff in_off = ifs.tellg(); + TEST_REQUIRE(in_off == 0, "in_off not zero at start"); + ifs.seekg(total_size - 20, std::ios::beg); + in_off = ifs.tellg(); + TEST_REQUIRE(in_off == total_size - 20, "in_off incorrect after >32 bit seek"); + ifs.seekg(10, std::ios::cur); + in_off = ifs.tellg(); + TEST_REQUIRE(in_off == total_size - 10, "in_off incorrect after incremental seek"); + ifs.seekg(0, std::ios::end); + in_off = ifs.tellg(); + TEST_REQUIRE(in_off == total_size, "in_off incorrect after seek to end"); + } + std::remove(p.c_str()); +} + +int main(int, char**) { + // This test assumes and requires that std::streamoff is larger than + // 32 bit - this is not required in the standard itself. + static_assert(sizeof(std::streamoff) > 4, ""); + test_tellg(0x100000042ULL); + return 0; +}