[libc-commits] [libc] [libc] Add getgrent, setgrent, and endgrent entrypoints (PR #224372)

[Jeff Bailey via libc-commits]

================
@@ -0,0 +1,208 @@
+//===----------------------------------------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+///
+/// \file
+/// Unit tests for getgrent, setgrent, and endgrent.
+///
+//===----------------------------------------------------------------------===//
+
+#include "hdr/errno_macros.h"
+#include "hdr/types/gid_t.h"
+#include "hdr/types/size_t.h"
+#include "hdr/types/struct_group.h"
+#include "src/__support/libc_errno.h"
+#include "src/grp/endgrent.h"
+#include "src/grp/getgrent.h"
+#include "src/grp/grp_utils.h"
+#include "src/grp/setgrent.h"
+#include "test/UnitTest/Test.h"
+#include "test/src/grp/grp_test_utils.h"
+
+using LIBC_NAMESPACE::libc_errno;
+
+TEST_F(LlvmLibcGrpTest, GetGrentTestSuccess) {
+  constexpr char CONTENT[] = "root:x:0:root\n"
+                             "bin:x:1:bin,daemon\n"
+                             "wheel:x:10:root,admin,user1\n";
+  ScopedGroupFile test_file(libc_make_test_file_path("getgrent_success.test"),
+                            CONTENT);
+
+  struct group *grp = LIBC_NAMESPACE::getgrent();
+  ASSERT_NE(grp, nullptr);
+  EXPECT_STREQ(grp->gr_name, "root");
+  EXPECT_STREQ(grp->gr_passwd, "x");
+  EXPECT_EQ(grp->gr_gid, static_cast<gid_t>(0));
+  ASSERT_NE(grp->gr_mem, nullptr);
+  EXPECT_STREQ(grp->gr_mem[0], "root");
+  EXPECT_EQ(grp->gr_mem[1], nullptr);
+
+  grp = LIBC_NAMESPACE::getgrent();
+  ASSERT_NE(grp, nullptr);
+  EXPECT_STREQ(grp->gr_name, "bin");
+  EXPECT_STREQ(grp->gr_passwd, "x");
+  EXPECT_EQ(grp->gr_gid, static_cast<gid_t>(1));
+  ASSERT_NE(grp->gr_mem, nullptr);
+  EXPECT_STREQ(grp->gr_mem[0], "bin");
+  EXPECT_STREQ(grp->gr_mem[1], "daemon");
+  EXPECT_EQ(grp->gr_mem[2], nullptr);
+
+  grp = LIBC_NAMESPACE::getgrent();
+  ASSERT_NE(grp, nullptr);
+  EXPECT_STREQ(grp->gr_name, "wheel");
+  EXPECT_STREQ(grp->gr_passwd, "x");
+  EXPECT_EQ(grp->gr_gid, static_cast<gid_t>(10));
+  ASSERT_NE(grp->gr_mem, nullptr);
+  EXPECT_STREQ(grp->gr_mem[0], "root");
+  EXPECT_STREQ(grp->gr_mem[1], "admin");
+  EXPECT_STREQ(grp->gr_mem[2], "user1");
+  EXPECT_EQ(grp->gr_mem[3], nullptr);
+
+  // At EOF, getgrent returns nullptr without altering errno.
+  libc_errno = 0;
+  grp = LIBC_NAMESPACE::getgrent();
+  EXPECT_EQ(grp, nullptr);
+  ASSERT_ERRNO_SUCCESS();
+
+  LIBC_NAMESPACE::endgrent();
+}
+
+TEST_F(LlvmLibcGrpTest, GetGrentTestFailure) {
+  constexpr char CONTENT[] = "malformed_line_without_colons\n";
+  ScopedGroupFile test_file(libc_make_test_file_path("getgrent_failure.test"),
+                            CONTENT);
+
+  struct group *grp = LIBC_NAMESPACE::getgrent();
+  EXPECT_EQ(grp, nullptr);
+  ASSERT_ERRNO_EQ(EINVAL);
+
+  LIBC_NAMESPACE::endgrent();
+}
+
+TEST_F(LlvmLibcGrpTest, SetGrentTestHermetic) {
+  constexpr char CONTENT[] = "root:x:0:root\n"
+                             "bin:x:1:bin\n";
+  ScopedGroupFile test_file(libc_make_test_file_path("setgrent_hermetic.test"),
+                            CONTENT);
+
+  struct group *grp = LIBC_NAMESPACE::getgrent();
+  ASSERT_NE(grp, nullptr);
+  EXPECT_STREQ(grp->gr_name, "root");
+
+  // Rewind the group database stream to the beginning.
+  LIBC_NAMESPACE::setgrent();
+
+  grp = LIBC_NAMESPACE::getgrent();
+  ASSERT_NE(grp, nullptr);
+  EXPECT_STREQ(grp->gr_name, "root");
+
+  LIBC_NAMESPACE::endgrent();
+}
+
+TEST_F(LlvmLibcGrpTest, ReopenAfterEndgrent) {
+  constexpr char CONTENT[] = "root:x:0:root\n"
+                             "bin:x:1:bin\n";
+  ScopedGroupFile test_file(libc_make_test_file_path("reopen_after_end.test"),
+                            CONTENT);
+
+  struct group *grp = LIBC_NAMESPACE::getgrent();
+  ASSERT_NE(grp, nullptr);
+  EXPECT_STREQ(grp->gr_name, "root");
+
+  LIBC_NAMESPACE::endgrent();
+
+  // endgrent closes the stream without invalidating the last returned pointer.
+  EXPECT_STREQ(grp->gr_name, "root");
+
+  // Subsequent getgrent after endgrent reopens the database from the start.
+  grp = LIBC_NAMESPACE::getgrent();
+  ASSERT_NE(grp, nullptr);
+  EXPECT_STREQ(grp->gr_name, "root");
+
+  LIBC_NAMESPACE::endgrent();
+}
+
+TEST_F(LlvmLibcGrpTest, FileOpenFailure) {
+  auto nonexistent_path = libc_make_test_file_path("getgrent_nonexistent.test");
+  LIBC_NAMESPACE::grp::TESTONLY_set_group_path(nonexistent_path);
+
+  struct group *grp = LIBC_NAMESPACE::getgrent();
+  EXPECT_EQ(grp, nullptr);
+  ASSERT_ERRNO_EQ(ENOENT);
+
+  // POSIX specifies that setgrent() sets errno on error.
+  libc_errno = 0;
+  LIBC_NAMESPACE::setgrent();
+  ASSERT_ERRNO_EQ(ENOENT);
+}
+
+TEST_F(LlvmLibcGrpTest, BlankLines) {
+  constexpr char CONTENT[] = "\n"
+                             "root:x:0:root\n"
+                             "\n"
+                             "\n"
+                             "bin:x:1:bin\n"
+                             "\n";
+  ScopedGroupFile test_file(libc_make_test_file_path("getgrent_blank.test"),
+                            CONTENT);
+
+  struct group *grp = LIBC_NAMESPACE::getgrent();
+  ASSERT_NE(grp, nullptr);
+  EXPECT_STREQ(grp->gr_name, "root");
+
+  grp = LIBC_NAMESPACE::getgrent();
+  ASSERT_NE(grp, nullptr);
+  EXPECT_STREQ(grp->gr_name, "bin");
+
+  // POSIX mandates that getgrent shall return null and not change errno on EOF.
+  libc_errno = ENOENT;
+  grp = LIBC_NAMESPACE::getgrent();
+  EXPECT_EQ(grp, nullptr);
+  ASSERT_ERRNO_EQ(ENOENT);
+
+  LIBC_NAMESPACE::endgrent();
+}
+
+TEST_F(LlvmLibcGrpTest, DynamicMemberAndLineGrowth) {
+  // Construct a record with 600 members (~3 KB), exercising both dynamic line
+  // growth and per-record sizing of the gr_mem pointer array.
+  constexpr size_t MEMBER_COUNT = 600;
+  constexpr size_t FILE_BUFFER_SIZE = 8192;
+  char content[FILE_BUFFER_SIZE];
+  size_t offset = 0;
+  constexpr char HEADER[] = "biggroup:x:2000:";
+  for (size_t i = 0; HEADER[i] != '\0'; ++i)
+    content[offset++] = HEADER[i];
+
+  for (size_t i = 0; i < MEMBER_COUNT; ++i) {
+    if (i > 0)
+      content[offset++] = ',';
+    content[offset++] = 'u';
+    content[offset++] = '0' + (i / 100) % 10;
+    content[offset++] = '0' + (i / 10) % 10;
+    content[offset++] = '0' + (i % 10);
----------------
kaladron wrote:

I've done the change.  EBCDICFTW! =)

https://github.com/llvm/llvm-project/pull/224372