[libc-commits] [libc] [libc] implement mkstemp (PR #199220)

[Michael Jones via libc-commits]

================
@@ -0,0 +1,182 @@
+//===-- Unittests for mkstemp ---------------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#include "hdr/errno_macros.h"
+#include "hdr/fcntl_macros.h"
+#include "hdr/signal_macros.h"
+#include "src/stdlib/mkstemp.h"
+#include "src/string/strdup.h"
+#include "src/unistd/access.h"
+#include "src/unistd/close.h"
+#include "src/unistd/read.h"
+#include "src/unistd/unlink.h"
+#include "src/unistd/write.h"
+#include "test/UnitTest/ErrnoCheckingTest.h"
+#include "test/UnitTest/Test.h"
+
+using LlvmLibcMkstempTest = LIBC_NAMESPACE::testing::ErrnoCheckingTest;
+
+TEST_F(LlvmLibcMkstempTest, ValidTemplate) {
+  char *tmpl = LIBC_NAMESPACE::strdup(libc_make_test_file_path("tmp_XXXXXX"));
+  int fd = LIBC_NAMESPACE::mkstemp(tmpl);
+  ASSERT_GE(fd, 0);
+  LIBC_NAMESPACE::close(fd);
+  LIBC_NAMESPACE::unlink(tmpl);
+  ::free(tmpl);
+}
+
+TEST_F(LlvmLibcMkstempTest, TemplateModifiedInPlace) {
+  char *tmpl = LIBC_NAMESPACE::strdup(libc_make_test_file_path("tmp_XXXXXX"));
+  size_t len = 0;
+  while (tmpl[len] != '\0')
+    len++;
+  size_t count = 0;
+  for (size_t i = len; i > 0 && tmpl[i - 1] == 'X'; i--)
+    count++;
+  int fd = LIBC_NAMESPACE::mkstemp(tmpl);
+  ASSERT_GE(fd, 0);
+  bool modified = false;
+  for (size_t i = len - count; i < len; i++)
+    if (tmpl[i] != 'X') {
+      modified = true;
+      break;
+    }
+  EXPECT_TRUE(modified);
+  LIBC_NAMESPACE::close(fd);
+  LIBC_NAMESPACE::unlink(tmpl);
+  ::free(tmpl);
+}
+
+TEST_F(LlvmLibcMkstempTest, FileExists) {
+  char *tmpl = LIBC_NAMESPACE::strdup(libc_make_test_file_path("tmp_XXXXXX"));
+  int fd = LIBC_NAMESPACE::mkstemp(tmpl);
+  ASSERT_GE(fd, 0);
+  EXPECT_EQ(LIBC_NAMESPACE::access(tmpl, F_OK), 0);
+  LIBC_NAMESPACE::close(fd);
+  LIBC_NAMESPACE::unlink(tmpl);
+  ::free(tmpl);
+}
+
+TEST_F(LlvmLibcMkstempTest, FdIsWritable) {
+  char *tmpl = LIBC_NAMESPACE::strdup(libc_make_test_file_path("tmp_XXXXXX"));
+  int fd = LIBC_NAMESPACE::mkstemp(tmpl);
+  ASSERT_GE(fd, 0);
+  const char msg[] = "hello";
+  EXPECT_EQ(LIBC_NAMESPACE::write(fd, msg, 5), static_cast<ssize_t>(5));
+  LIBC_NAMESPACE::close(fd);
+  LIBC_NAMESPACE::unlink(tmpl);
+  ::free(tmpl);
+}
----------------
michaelrj-google wrote:

these tests can be combined, since they're effectively testing the same thing: Was the file opened correctly.

https://github.com/llvm/llvm-project/pull/199220