diff --git a/include/ziparchive/zip_archive.h b/include/ziparchive/zip_archive.h index ac3d79288..18774948f 100644 --- a/include/ziparchive/zip_archive.h +++ b/include/ziparchive/zip_archive.h @@ -152,7 +152,10 @@ int32_t StartIteration(ZipArchiveHandle handle, void** cookie_ptr, int32_t Next(void* cookie, ZipEntry* data, ZipEntryName *name); /* - * Uncompress and write an entry to a file descriptor. + * Uncompress and write an entry to an open file identified by |fd|. + * |entry->uncompressed_length| bytes will be written to the file at + * its current offset, and the file will be truncated at the end of + * the uncompressed data. * * Returns 0 on success and negative values on failure. */ diff --git a/libziparchive/zip_archive.cc b/libziparchive/zip_archive.cc index dddff1fb5..2b827b3af 100644 --- a/libziparchive/zip_archive.cc +++ b/libziparchive/zip_archive.cc @@ -1007,13 +1007,21 @@ int32_t ExtractEntryToFile(ZipArchiveHandle handle, ZipEntry* entry, int fd) { const int32_t declared_length = entry->uncompressed_length; - int result = TEMP_FAILURE_RETRY(ftruncate(fd, declared_length)); - if (result == -1) { - ALOGW("Zip: unable to truncate file to %ud", declared_length); + const off64_t current_offset = lseek64(fd, 0, SEEK_CUR); + if (current_offset == -1) { + ALOGW("Zip: unable to seek to current location on fd %d: %s", fd, + strerror(errno)); return kIoError; } - android::FileMap* map = MapFileSegment(fd, 0, declared_length, + int result = TEMP_FAILURE_RETRY(ftruncate(fd, declared_length + current_offset)); + if (result == -1) { + ALOGW("Zip: unable to truncate file to %lld: %s", declared_length + current_offset, + strerror(errno)); + return kIoError; + } + + android::FileMap* map = MapFileSegment(fd, current_offset, declared_length, false, kTempMappingFileName); if (map == NULL) { return kMmapFailed; diff --git a/libziparchive/zip_archive_test.cc b/libziparchive/zip_archive_test.cc index 55cb755f3..022be5b6f 100644 --- a/libziparchive/zip_archive_test.cc +++ b/libziparchive/zip_archive_test.cc @@ -16,8 +16,12 @@ #include "ziparchive/zip_archive.h" -#include "getopt.h" +#include +#include #include +#include +#include + #include static std::string test_data_dir; @@ -136,6 +140,43 @@ TEST(ziparchive, ExtractToMemory) { CloseArchive(handle); } +TEST(ziparchive, ExtractToFile) { + char kTempFilePattern[] = "zip_archive_test_XXXXXX"; + int fd = mkstemp(kTempFilePattern); + ASSERT_NE(-1, fd); + const uint8_t data[8] = { '1', '2', '3', '4', '5', '6', '7', '8' }; + const ssize_t data_size = sizeof(data); + + ASSERT_EQ(data_size, TEMP_FAILURE_RETRY(write(fd, data, data_size))); + + ZipArchiveHandle handle; + ASSERT_EQ(0, OpenArchiveWrapper(kValidZip, &handle)); + + ZipEntry entry; + ASSERT_EQ(0, FindEntry(handle, "a.txt", &entry)); + ASSERT_EQ(0, ExtractEntryToFile(handle, &entry, fd)); + + + // Assert that the first 8 bytes of the file haven't been clobbered. + uint8_t read_buffer[data_size]; + ASSERT_EQ(0, lseek64(fd, 0, SEEK_SET)); + ASSERT_EQ(data_size, TEMP_FAILURE_RETRY(read(fd, read_buffer, data_size))); + ASSERT_EQ(0, memcmp(read_buffer, data, data_size)); + + // Assert that the remainder of the file contains the incompressed data. + std::vector uncompressed_data(entry.uncompressed_length); + ASSERT_EQ(static_cast(entry.uncompressed_length), + TEMP_FAILURE_RETRY( + read(fd, &uncompressed_data[0], entry.uncompressed_length))); + ASSERT_EQ(0, memcmp(&uncompressed_data[0], kATxtContents, + sizeof(kATxtContents))); + + // Assert that the total length of the file is sane + ASSERT_EQ(data_size + sizeof(kATxtContents), lseek64(fd, 0, SEEK_END)); + + close(fd); +} + int main(int argc, char** argv) { ::testing::InitGoogleTest(&argc, argv);