diff options
Diffstat (limited to 'src/xz/file_io.h')
| -rw-r--r-- | src/xz/file_io.h | 34 |
1 files changed, 28 insertions, 6 deletions
diff --git a/src/xz/file_io.h b/src/xz/file_io.h index b0bbe11a..58bf7b5e 100644 --- a/src/xz/file_io.h +++ b/src/xz/file_io.h @@ -11,13 +11,22 @@ /////////////////////////////////////////////////////////////////////////////// // Some systems have suboptimal BUFSIZ. Use a bit bigger value on them. +// We also need that IO_BUFFER_SIZE is a multiple of 8 (sizeof(uint64_t)) #if BUFSIZ <= 1024 # define IO_BUFFER_SIZE 8192 #else -# define IO_BUFFER_SIZE BUFSIZ +# define IO_BUFFER_SIZE (BUFSIZ & ~7U) #endif +/// is_sparse() accesses the buffer as uint64_t for maximum speed. +/// Use an union to make sure that the buffer is properly aligned. +typedef union { + uint8_t u8[IO_BUFFER_SIZE]; + uint64_t u64[IO_BUFFER_SIZE / sizeof(uint64_t)]; +} io_buf; + + typedef struct { /// Name of the source filename (as given on the command line) or /// pointer to static "(stdin)" when reading from standard input. @@ -33,15 +42,24 @@ typedef struct { /// File descriptor of the target file int dest_fd; + /// True once end of the source file has been detected. + bool src_eof; + + /// If true, we look for long chunks of zeros and try to create + /// a sparse file. + bool dest_try_sparse; + + /// This is used only if dest_try_sparse is true. This holds the + /// number of zero bytes we haven't written out, because we plan + /// to make that byte range a sparse chunk. + off_t dest_pending_sparse; + /// Stat of the source file. struct stat src_st; /// Stat of the destination file. struct stat dest_st; - /// True once end of the source file has been detected. - bool src_eof; - } file_pair; @@ -49,6 +67,10 @@ typedef struct { extern void io_init(void); +/// \brief Disable creation of sparse files when decompressing +extern void io_no_sparse(void); + + /// \brief Opens a file pair extern file_pair *io_open(const char *src_name); @@ -72,7 +94,7 @@ extern void io_close(file_pair *pair, bool success); /// \return On success, number of bytes read is returned. On end of /// file zero is returned and pair->src_eof set to true. /// On error, SIZE_MAX is returned and error message printed. -extern size_t io_read(file_pair *pair, uint8_t *buf, size_t size); +extern size_t io_read(file_pair *pair, io_buf *buf, size_t size); /// \brief Writes a buffer to the destination file @@ -83,4 +105,4 @@ extern size_t io_read(file_pair *pair, uint8_t *buf, size_t size); /// /// \return On success, zero is returned. On error, -1 is returned /// and error message printed. -extern bool io_write(const file_pair *pair, const uint8_t *buf, size_t size); +extern bool io_write(file_pair *pair, const io_buf *buf, size_t size); |