[PATCH 3/5] vircommand: Unify mass FD closing
We have two version of mass FD closing: one for FreeBSD (because
it has closefrom()) and the other for everything else. But now
that we have closefrom() wrapper even for Linux, we can unify
these two.
Signed-off-by: Michal Privoznik <mprivozn(a)redhat.com>
---
src/util/vircommand.c | 85 +++++++++++++------------------------------
1 file changed, 25 insertions(+), 60 deletions(-)
diff --git a/src/util/vircommand.c b/src/util/vircommand.c
index 49abb53c28..867f45b57b 100644
--- a/src/util/vircommand.c
+++ b/src/util/vircommand.c
@@ -526,60 +526,6 @@ virCommandMassCloseGetFDsGeneric(virCommand *cmd G_GNUC_UNUSED,
}
# endif /* !__linux__ */
-# ifdef __FreeBSD__
-
-static int
-virCommandMassClose(virCommand *cmd,
- int childin,
- int childout,
- int childerr)
-{
- int lastfd = -1;
- int fd = -1;
- size_t i;
-
- /*
- * Two phases of closing.
- *
- * The first (inefficient) phase iterates over FDs,
- * preserving certain FDs we need to pass down, and
- * closing others. The number of iterations is bounded
- * to the number of the biggest FD we need to preserve.
- *
- * The second (speedy) phase uses closefrom() to cull
- * all remaining FDs in the process.
- *
- * Usually the first phase will be fairly quick only
- * processing a handful of low FD numbers, and thus using
- * closefrom() is a massive win for high ulimit() NFILES
- * values.
- */
- lastfd = MAX(lastfd, childin);
- lastfd = MAX(lastfd, childout);
- lastfd = MAX(lastfd, childerr);
-
- for (i = 0; i < cmd->npassfd; i++)
- lastfd = MAX(lastfd, cmd->passfd[i].fd);
-
- for (fd = 0; fd <= lastfd; fd++) {
- if (fd == childin || fd == childout || fd == childerr)
- continue;
- if (!virCommandFDIsSet(cmd, fd)) {
- int tmpfd = fd;
- VIR_MASS_CLOSE(tmpfd);
- } else if (virSetInherit(fd, true) < 0) {
- virReportSystemError(errno, _("failed to preserve fd %1$d"), fd);
- return -1;
- }
- }
-
- closefrom(lastfd + 1);
-
- return 0;
-}
-
-# else /* ! __FreeBSD__ */
-
static int
virCommandMassClose(virCommand *cmd,
int childin,
@@ -588,7 +534,9 @@ virCommandMassClose(virCommand *cmd,
{
g_autoptr(virBitmap) fds = NULL;
int openmax = sysconf(_SC_OPEN_MAX);
+ int lastfd = -1;
int fd = -1;
+ size_t i;
/* In general, it is not safe to call malloc() between fork() and exec()
* because the child might have forked at the worst possible time, i.e.
@@ -605,16 +553,23 @@ virCommandMassClose(virCommand *cmd,
fds = virBitmapNew(openmax);
-# ifdef __linux__
+# ifdef __linux__
if (virCommandMassCloseGetFDsLinux(cmd, fds) < 0)
return -1;
-# else
+# else
if (virCommandMassCloseGetFDsGeneric(cmd, fds) < 0)
return -1;
-# endif
+# endif
+
+ lastfd = MAX(lastfd, childin);
+ lastfd = MAX(lastfd, childout);
+ lastfd = MAX(lastfd, childerr);
+
+ for (i = 0; i < cmd->npassfd; i++)
+ lastfd = MAX(lastfd, cmd->passfd[i].fd);
fd = virBitmapNextSetBit(fds, 2);
- for (; fd >= 0; fd = virBitmapNextSetBit(fds, fd)) {
+ for (; fd >= 0 && fd <= lastfd; fd = virBitmapNextSetBit(fds, fd)) {
if (fd == childin || fd == childout || fd == childerr)
continue;
if (!virCommandFDIsSet(cmd, fd)) {
@@ -626,11 +581,21 @@ virCommandMassClose(virCommand *cmd,
}
}
+ if (virCloseFrom(lastfd + 1) < 0) {
+ if (errno != ENOSYS)
+ return -1;
+
+ if (fd > 0) {
+ for (; fd >= 0; fd = virBitmapNextSetBit(fds, fd)) {
+ int tmpfd = fd;
+ VIR_MASS_CLOSE(tmpfd);
+ }
+ }
+ }
+
return 0;
}
-# endif /* ! __FreeBSD__ */
-
/*
* virExec:
--
2.41.0