diff options
| -rw-r--r-- | coreutils/uudecode.c | 17 |
1 files changed, 12 insertions, 5 deletions
diff --git a/coreutils/uudecode.c b/coreutils/uudecode.c index 751976a87..10e5a55de 100644 --- a/coreutils/uudecode.c +++ b/coreutils/uudecode.c @@ -286,13 +286,19 @@ int baseNUM_main(int argc UNUSED_PARAM, char **argv) } else { enum { SRC_BUF_SIZE = 3 * 5 * 32, /* this *MUST* be a multiple of 3 and 5 */ - DST_BUF_SIZE = 4 * ((SRC_BUF_SIZE + 2) / 3), + DST_BUF_SIZE = 8 * ((SRC_BUF_SIZE + 4) / 5), /* max growth on decode (base32 case) */ }; - char src_buf[SRC_BUF_SIZE]; - char dst_buf[DST_BUF_SIZE + 1]; - int src_fd = fileno(src_stream); - int rem = 0; + /* Use one buffer for both input and output: + * decoding reads input "left-to-right", + * it's safe to place source at the end of the buffer and + * overwrite it while decoding, just be careful to have a gap. + */ + char dst_buf[((DST_BUF_SIZE + /*gap:*/ 16) /*round up to 16:*/ | 0xf) + 1]; +#define src_buf (dst_buf + sizeof(dst_buf) - SRC_BUF_SIZE) + int src_fd, rem; + src_fd = fileno(src_stream); + rem = 0; while (1) { size_t size = full_read(src_fd, src_buf, SRC_BUF_SIZE); if ((ssize_t)size < 0) @@ -331,6 +337,7 @@ int baseNUM_main(int argc UNUSED_PARAM, char **argv) } } } +#undef src_buf } fflush_stdout_and_exit(EXIT_SUCCESS); |