diff options
| -rw-r--r-- | libstore/rdwr.c | 36 |
1 files changed, 22 insertions, 14 deletions
diff --git a/libstore/rdwr.c b/libstore/rdwr.c index 26f713eb..bb3f3079 100644 --- a/libstore/rdwr.c +++ b/libstore/rdwr.c @@ -1,9 +1,7 @@ /* Store I/O - Copyright (C) 1995, 1996 Free Software Foundation, Inc. - + Copyright (C) 1995, 1996, 1997 Free Software Foundation, Inc. Written by Miles Bader <miles@gnu.ai.mit.edu> - This file is part of the GNU Hurd. The GNU Hurd is free software; you can redistribute it and/or @@ -18,7 +16,7 @@ You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., - 675 Mass Ave, Cambridge, MA 02139, USA. */ + 59 Temple Place - Suite 330, Boston, MA 02111, USA. */ #include <string.h> @@ -165,22 +163,28 @@ error_t store_read (struct store *store, off_t addr, size_t amount, void **buf, size_t *len) { - error_t err; size_t index; - off_t base; + off_t base, first_run_size; struct store_run *run, *runs_end; int block_shift = store->log2_block_size; store_read_meth_t read = store->class->read; addr = store_find_first_run (store, addr, &run, &runs_end, &base, &index); - if (addr < 0) - err = EIO; - else if ((run->length << block_shift) >= amount) + if (addr < 0 || run->start < 0) + return EIO; /* Reading from a hole. */ + + first_run_size = (run->length << block_shift); + if (first_run_size >= amount) /* The first run has it all... */ - err = (*read)(store, base + run->start + addr, index, amount, buf, len); + { + if (first_run_size < amount) + amount = first_run_size; + return (*read)(store, base + run->start + addr, index, amount, buf, len); + } else /* ARGH, we've got to split up the read ... This isn't fun. */ { + error_t err; int all; /* WHOLE_BUF and WHOLE_BUF_LEN will point to a buff that's large enough to hold the entire request. This is initially whatever the user @@ -205,7 +209,11 @@ store_read (struct store *store, to use the buffer space we so kindly gave it, bcopy it to that space. */ if (seg_buf != buf_end) - bcopy (seg_buf, buf_end, seg_buf_len); + { + bcopy (seg_buf, buf_end, seg_buf_len); + vm_deallocate (mach_task_self (), + (vm_address_t)seg_buf, seg_buf_len); + } buf_end += seg_buf_len; amount -= seg_buf_len; *all = (seg_buf_len == len); @@ -226,7 +234,7 @@ store_read (struct store *store, buf_end = whole_buf; - err = seg_read (base + run->start + addr, run->length << block_shift, &all); + err = seg_read (base + run->start + addr, first_run_size, &all); while (!err && all && amount > 0 && store_next_run (store, runs_end, &run, &base, &index)) { @@ -263,8 +271,8 @@ store_read (struct store *store, unused); *buf = whole_buf; } - } - return err; + return err; + } } |