diff --git a/base/file.cpp b/base/file.cpp index f444c0c64..bcdfc5e99 100644 --- a/base/file.cpp +++ b/base/file.cpp @@ -149,5 +149,32 @@ bool WriteFully(int fd, const void* data, size_t byte_count) { return true; } +bool RemoveFileIfExists(const std::string& path, std::string* err) { + struct stat st; +#if defined(_WIN32) + //TODO: Windows version can't handle symbol link correctly. + int result = stat(path.c_str(), &st); + bool file_type_removable = (result == 0 && S_ISREG(st.st_mode)); +#else + int result = lstat(path.c_str(), &st); + bool file_type_removable = (result == 0 && (S_ISREG(st.st_mode) || S_ISLNK(st.st_mode))); +#endif + if (result == 0) { + if (!file_type_removable) { + if (err != nullptr) { + *err = "is not a regular or symbol link file"; + } + return false; + } + if (unlink(path.c_str()) == -1) { + if (err != nullptr) { + *err = strerror(errno); + } + return false; + } + } + return true; +} + } // namespace base } // namespace android diff --git a/base/file_test.cpp b/base/file_test.cpp index 1bf83a49f..17755bfed 100644 --- a/base/file_test.cpp +++ b/base/file_test.cpp @@ -96,3 +96,17 @@ TEST(file, WriteFully) { s.resize(1024); ASSERT_FALSE(android::base::ReadFully(tf.fd, &s[0], s.size())); } + +TEST(file, RemoveFileIfExist) { + TemporaryFile tf; + ASSERT_TRUE(tf.fd != -1); + close(tf.fd); + tf.fd = -1; + std::string err; + ASSERT_TRUE(android::base::RemoveFileIfExists(tf.path, &err)) << err; + ASSERT_TRUE(android::base::RemoveFileIfExists(tf.path)); + TemporaryDir td; + ASSERT_FALSE(android::base::RemoveFileIfExists(td.path)); + ASSERT_FALSE(android::base::RemoveFileIfExists(td.path, &err)); + ASSERT_EQ("is not a regular or symbol link file", err); +} diff --git a/base/include/android-base/file.h b/base/include/android-base/file.h index acd29b30e..486befcbb 100644 --- a/base/include/android-base/file.h +++ b/base/include/android-base/file.h @@ -37,6 +37,8 @@ bool WriteStringToFile(const std::string& content, const std::string& path, bool ReadFully(int fd, void* data, size_t byte_count); bool WriteFully(int fd, const void* data, size_t byte_count); +bool RemoveFileIfExists(const std::string& path, std::string* err = nullptr); + } // namespace base } // namespace android