diff options
Diffstat (limited to 'lib/libc/gen/telldir.c')
| -rw-r--r-- | lib/libc/gen/telldir.c | 37 |
1 files changed, 37 insertions, 0 deletions
diff --git a/lib/libc/gen/telldir.c b/lib/libc/gen/telldir.c index d72b500..19cd6ee 100644 --- a/lib/libc/gen/telldir.c +++ b/lib/libc/gen/telldir.c @@ -101,9 +101,22 @@ _seekdir(dirp, loc) return; if (lp->loc_loc == dirp->dd_loc && lp->loc_seek == dirp->dd_seek) return; + + /* If it's within the same chunk of data, don't bother reloading. */ + if (lp->loc_seek == dirp->dd_seek) { + /* + * If we go back to 0 don't make the next readdir + * trigger a call to getdirentries(). + */ + if (lp->loc_loc == 0) + dirp->dd_flags |= __DTF_SKIPREAD; + dirp->dd_loc = lp->loc_loc; + return; + } (void) lseek(dirp->dd_fd, (off_t)lp->loc_seek, SEEK_SET); dirp->dd_seek = lp->loc_seek; dirp->dd_loc = 0; + dirp->dd_flags &= ~__DTF_SKIPREAD; /* current contents are invalid */ while (dirp->dd_loc < lp->loc_loc) { dp = _readdir_unlocked(dirp, 0); if (dp == NULL) @@ -112,6 +125,30 @@ _seekdir(dirp, loc) } /* + * After readdir returns the last entry in a block, a call to telldir + * returns a location that is after the end of that last entry. + * However, that location doesn't refer to a valid directory entry. + * Ideally, the call to telldir would return a location that refers to + * the first entry in the next block. That location is not known + * until the next block is read, so readdir calls this function after + * fetching a new block to fix any such telldir locations. + */ +void +_fixtelldir(DIR *dirp, long oldseek, long oldloc) +{ + struct ddloc *lp; + + lp = LIST_FIRST(&dirp->dd_td->td_locq); + if (lp != NULL) { + if (lp->loc_loc == oldloc && + lp->loc_seek == oldseek) { + lp->loc_seek = dirp->dd_seek; + lp->loc_loc = dirp->dd_loc; + } + } +} + +/* * Reclaim memory for telldir cookies which weren't used. */ void |
