liblp: Enable building on Windows.

Bug: 119689480
Test: builds when fastboot.exe uses liblp
Change-Id: I8ba2ad51d806c4650a0f35d41e4906b703d4661d

fs_mgr/liblp/Android.bp

@@ -39,6 +39,11 @@ cc_library {
         "libext4_utils",
         "libz",
     ],
+    target: {
+        windows: {
+            enabled: true,
+        },
+    },
     export_include_dirs: ["include"],
 }
 

fs_mgr/liblp/images.cpp

@@ -27,6 +27,12 @@
 namespace android {
 namespace fs_mgr {
 
+using android::base::unique_fd;
+
+#if defined(_WIN32)
+static const int O_NOFOLLOW = 0;
+#endif
+
 std::unique_ptr<LpMetadata> ReadFromImageFile(int fd) {
     std::unique_ptr<uint8_t[]> buffer = std::make_unique<uint8_t[]>(LP_METADATA_GEOMETRY_SIZE);
     if (SeekFile64(fd, 0, SEEK_SET) < 0) {
@@ -62,7 +68,7 @@ std::unique_ptr<LpMetadata> ReadFromImageBlob(const void* data, size_t bytes) {
 }
 
 std::unique_ptr<LpMetadata> ReadFromImageFile(const char* file) {
-    android::base::unique_fd fd(open(file, O_RDONLY | O_CLOEXEC));
+    unique_fd fd(open(file, O_RDONLY | O_CLOEXEC));
     if (fd < 0) {
         PERROR << __PRETTY_FUNCTION__ << " open failed: " << file;
         return nullptr;
@@ -84,7 +90,7 @@ bool WriteToImageFile(int fd, const LpMetadata& input) {
 }
 
 bool WriteToImageFile(const char* file, const LpMetadata& input) {
-    android::base::unique_fd fd(open(file, O_CREAT | O_RDWR | O_TRUNC | O_CLOEXEC, 0644));
+    unique_fd fd(open(file, O_CREAT | O_RDWR | O_TRUNC | O_CLOEXEC, 0644));
     if (fd < 0) {
         PERROR << __PRETTY_FUNCTION__ << " open failed: " << file;
         return false;
@@ -143,7 +149,7 @@ bool SparseBuilder::IsValid() const {
 }
 
 bool SparseBuilder::Export(const char* file) {
-    android::base::unique_fd fd(open(file, O_CREAT | O_RDWR | O_TRUNC | O_CLOEXEC, 0644));
+    unique_fd fd(open(file, O_CREAT | O_RDWR | O_TRUNC | O_CLOEXEC, 0644));
     if (fd < 0) {
         PERROR << "open failed: " << file;
         return false;
@@ -162,19 +168,15 @@ bool SparseBuilder::Export(const char* file) {
 }
 
 bool SparseBuilder::ExportFiles(const std::string& output_dir) {
-    android::base::unique_fd dir(open(output_dir.c_str(), O_CLOEXEC | O_DIRECTORY | O_NOFOLLOW));
-    if (dir < 0) {
-        PERROR << "open dir failed: " << output_dir;
-        return false;
-    }
-
     for (size_t i = 0; i < device_images_.size(); i++) {
         std::string name = GetBlockDevicePartitionName(metadata_.block_devices[i]);
-        std::string path = output_dir + "/super_" + name + ".img";
-        android::base::unique_fd fd(openat(
-                dir, path.c_str(), O_CREAT | O_RDWR | O_TRUNC | O_CLOEXEC | O_NOFOLLOW, 0644));
+        std::string file_name = "super_" + name + ".img";
+        std::string file_path = output_dir + "/" + file_name;
+
+        static const int kOpenFlags = O_CREAT | O_RDWR | O_TRUNC | O_CLOEXEC | O_NOFOLLOW;
+        unique_fd fd(open(file_path.c_str(), kOpenFlags, 0644));
         if (fd < 0) {
-            PERROR << "open failed: " << path;
+            PERROR << "open failed: " << file_path;
             return false;
         }
         // No gzip compression; sparseify; no checksum.

fs_mgr/liblp/partition_opener.cpp

@@ -19,8 +19,9 @@
 #if defined(__linux__)
 #include <linux/fs.h>
 #endif
+#if !defined(_WIN32)
 #include <sys/ioctl.h>
-#include <sys/stat.h>
+#endif
 #include <sys/types.h>
 #include <unistd.h>
 
@@ -84,7 +85,7 @@ bool GetBlockDeviceInfo(const std::string& block_device, BlockDeviceInfo* device
 
 unique_fd PartitionOpener::Open(const std::string& partition_name, int flags) const {
     std::string path = GetPartitionAbsolutePath(partition_name);
-    return unique_fd{open(path.c_str(), flags)};
+    return unique_fd{open(path.c_str(), flags | O_CLOEXEC)};
 }
 
 bool PartitionOpener::GetInfo(const std::string& partition_name, BlockDeviceInfo* info) const {

fs_mgr/liblp/utility.cpp

@@ -29,6 +29,7 @@ namespace android {
 namespace fs_mgr {
 
 bool GetDescriptorSize(int fd, uint64_t* size) {
+#if !defined(_WIN32)
     struct stat s;
     if (fstat(fd, &s) < 0) {
         PERROR << __PRETTY_FUNCTION__ << "fstat failed";
@@ -39,6 +40,7 @@ bool GetDescriptorSize(int fd, uint64_t* size) {
         *size = get_block_device_size(fd);
         return *size != 0;
     }
+#endif
 
     int64_t result = SeekFile64(fd, 0, SEEK_END);
     if (result == -1) {

fs_mgr/liblp/writer.cpp

@@ -235,6 +235,10 @@ static bool DefaultWriter(int fd, const std::string& blob) {
     return android::base::WriteFully(fd, blob.data(), blob.size());
 }
 
+#if defined(_WIN32)
+static const int O_SYNC = 0;
+#endif
+
 bool FlashPartitionTable(const IPartitionOpener& opener, const std::string& super_partition,
                          const LpMetadata& metadata) {
     android::base::unique_fd fd = opener.Open(super_partition, O_RDWR | O_SYNC);