Add basic tests for <link.h>.
The dl_iterate_phdr test is new, but the exidx test is largely copy & paste
from ndk_translation.
Bug: http://b/31556066
Test: ran tests
Change-Id: If754f1459ef1d789ee98a89cd2215188edca51da
diff --git a/tests/link_test.cpp b/tests/link_test.cpp
new file mode 100644
index 0000000..ac3ccb9
--- /dev/null
+++ b/tests/link_test.cpp
@@ -0,0 +1,119 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <gtest/gtest.h>
+
+#include <link.h>
+
+TEST(link, dl_iterate_phdr_early_exit) {
+ static size_t call_count = 0;
+ ASSERT_EQ(123, dl_iterate_phdr([](dl_phdr_info*, size_t, void*) { ++call_count; return 123; },
+ nullptr));
+ ASSERT_EQ(1u, call_count);
+}
+
+TEST(link, dl_iterate_phdr) {
+ struct Functor {
+ static int Callback(dl_phdr_info* i, size_t s, void* data) {
+ reinterpret_cast<Functor*>(data)->DoChecks(i, s);
+ return 0;
+ }
+ void DoChecks(dl_phdr_info* info, size_t s) {
+ ASSERT_EQ(sizeof(dl_phdr_info), s);
+
+ // TODO: why does the entry for the main executable have a null dlpi_addr and no name anyway?
+ if (++count == 1 && info->dlpi_addr == 0) return;
+
+ ASSERT_TRUE(info->dlpi_name != nullptr);
+
+ // Find the first PT_LOAD program header so we can find the ELF header.
+ for (ElfW(Half) i = 0; i < info->dlpi_phnum; ++i) {
+ const ElfW(Phdr)* phdr = reinterpret_cast<const ElfW(Phdr)*>(&info->dlpi_phdr[i]);
+ if (phdr->p_type == PT_LOAD) {
+ const ElfW(Ehdr)* ehdr = reinterpret_cast<const ElfW(Ehdr)*>(info->dlpi_addr +
+ phdr->p_vaddr);
+ // Does it look like an ELF file?
+ ASSERT_EQ(0, memcmp(ehdr, ELFMAG, SELFMAG));
+ // Does the e_phnum match what dl_iterate_phdr told us?
+ ASSERT_EQ(info->dlpi_phnum, ehdr->e_phnum);
+ break;
+ }
+ }
+ }
+ size_t count;
+ } f = {};
+ ASSERT_EQ(0, dl_iterate_phdr(Functor::Callback, &f));
+}
+
+#if __arm__
+static uintptr_t read_exidx_func(uintptr_t* entry) {
+ int32_t offset = *entry;
+ // Sign-extend from int31 to int32.
+ if ((offset & 0x40000000) != 0) {
+ offset += -0x7fffffff - 1;
+ }
+ return reinterpret_cast<uintptr_t>(entry) + offset;
+}
+__attribute__((__unused__)) static void another_function_in_same_ELF_file() {}
+#endif
+
+TEST(link, dl_unwind_find_exidx) {
+#if __arm__
+ int count = 0;
+ struct eit_entry_t {
+ uintptr_t one;
+ uintptr_t two;
+ };
+ eit_entry_t* entries = reinterpret_cast<eit_entry_t*>(dl_unwind_find_exidx(
+ reinterpret_cast<_Unwind_Ptr>(read_exidx_func), &count));
+ ASSERT_TRUE(entries != nullptr);
+ ASSERT_GT(count, 0);
+
+ // Sanity checks
+ uintptr_t func = reinterpret_cast<uintptr_t>(read_exidx_func);
+ bool found = false;
+ for (int i = 0; i < count; ++i) {
+ // Entries must have bit 31 clear.
+ ASSERT_TRUE((entries[i].one & (1<<31)) == 0);
+
+ uintptr_t exidx_func = read_exidx_func(&entries[i].one);
+
+ // If our function is compiled for thumb, exception table contains our address - 1.
+ if (func == exidx_func || func == exidx_func + 1) found = true;
+
+ // Entries must be sorted. Some addresses may appear twice if function
+ // is compiled for arm.
+ if (i > 0) {
+ EXPECT_GE(exidx_func, read_exidx_func(&entries[i - 1].one)) << i;
+ }
+ }
+ ASSERT_TRUE(found);
+#else
+ GTEST_LOG_(INFO) << "dl_unwind_find_exidx is an ARM-only API\n";
+#endif
+}