diff options
Diffstat (limited to 'src/libunixonacid/dd_commit.c')
-rw-r--r-- | src/libunixonacid/dd_commit.c | 68 |
1 files changed, 0 insertions, 68 deletions
diff --git a/src/libunixonacid/dd_commit.c b/src/libunixonacid/dd_commit.c deleted file mode 100644 index 1c940d2..0000000 --- a/src/libunixonacid/dd_commit.c +++ /dev/null @@ -1,68 +0,0 @@ -/* ISC license. */ - -#include <unistd.h> -#include <errno.h> -#include <stdio.h> -#include <string.h> -#include <skalibs/stralloc.h> -#include <skalibs/djbunix.h> -#include <skalibs/random.h> -#include <skalibs/unix-transactional.h> - -static char const *mybasename (char const *s, size_t len) -{ - size_t i = len ; - while (i--) if (s[i] == '/') return s + i + 1 ; - return s ; -} - -int dd_commit (dirdescriptor_t *dd) -{ - dirdescriptor_t zero = DIRDESCRIPTOR_ZERO ; - size_t len = strlen(dd->lnkfn) ; - size_t oldbase = dd->new.len ; - size_t newlnkbase ; - char const *lnkbn = mybasename(dd->lnkfn, len) ; - if (!sadirname(&dd->new, dd->lnkfn, len)) return 0 ; - if (!stralloc_catb(&dd->new, "/", 1)) goto fail ; - if (sareadlink(&dd->new, dd->lnkfn) < 0) - { - size_t lnkbnbase = dd->new.len ; - if (errno != EINVAL) goto fail ; - if (!stralloc_cats(&dd->new, lnkbn)) goto fail ; - if (!random_sauniquename(&dd->new, 8)) goto fail ; - if (!stralloc_0(&dd->new)) goto fail ; - if (rename(dd->lnkfn, dd->new.s + oldbase) < 0) goto fail ; - /* /!\ race condition right here: there's no lnkfn in the fs */ - if (symlink(dd->new.s + lnkbnbase, dd->lnkfn) < 0) /* now that's VERY BAD if it fails */ - { - int e = errno ; - rename(dd->new.s + oldbase, dd->lnkfn) ; /* attempt to revert to initial situation */ - errno = e ; - goto fail ; /* and hope for the best */ - } - } - if (!stralloc_0(&dd->new)) goto fail ; - newlnkbase = dd->new.len ; - if (!stralloc_catb(&dd->new, dd->lnkfn, len)) goto fail ; - if (!random_sauniquename(&dd->new, 8)) goto fail ; - if (!stralloc_0(&dd->new)) goto fail ; - if (symlink(dd->new.s, dd->new.s + newlnkbase) < 0) goto fail ; - if (rename(dd->new.s + newlnkbase, dd->lnkfn) < 0) - { - int e = errno ; - unlink(dd->new.s + newlnkbase) ; - errno = e ; - goto fail ; - } - fd_close(dd->fd) ; - dd->new.len = newlnkbase ; - rm_rf_in_tmp(&dd->new, oldbase) ; - stralloc_free(&dd->new) ; - *dd = zero ; - return 1 ; - - fail: - dd->new.len = oldbase ; - return 0 ; -} |