diff options
| author | Zbigniew Jędrzejewski-Szmek <zbyszek@in.waw.pl> | 2014-01-25 23:35:28 -0500 |
|---|---|---|
| committer | Zbigniew Jędrzejewski-Szmek <zbyszek@in.waw.pl> | 2014-01-27 23:17:02 -0500 |
| commit | 65b3903ff576488eaabb51d3c4fbf9c73d867d7c (patch) | |
| tree | 0343e9d79057f6ca67acb87d6cc06f45ab7a1384 /src/shared/missing.h | |
| parent | 8e33886ec582336564ae11b80023abe93d7599c0 (diff) | |
journal: guarantee async-signal-safety in sd_journald_sendv
signal(7) provides a list of functions which may be called from a
signal handler. Other functions, which only call those functions and
don't access global memory and are reentrant are also safe.
sd_j_sendv was mostly OK, but would call mkostemp and writev in a
fallback path, which are unsafe.
Being able to call sd_j_sendv in a async-signal-safe way is important
because it allows it be used in signal handlers.
Safety is achieved by replacing mkostemp with open(O_TMPFILE) and an
open-coded writev replacement which uses write. Unfortunately,
O_TMPFILE is only available on kernels >= 3.11. When O_TMPFILE is
unavailable, an open-coded mkostemp is used.
https://bugzilla.gnome.org/show_bug.cgi?id=722889
Diffstat (limited to 'src/shared/missing.h')
| -rw-r--r-- | src/shared/missing.h | 16 |
1 files changed, 10 insertions, 6 deletions
diff --git a/src/shared/missing.h b/src/shared/missing.h index 6c038d9f08..4e62100030 100644 --- a/src/shared/missing.h +++ b/src/shared/missing.h @@ -301,25 +301,29 @@ static inline int name_to_handle_at(int fd, const char *name, struct file_handle #endif #ifndef CIFS_MAGIC_NUMBER -#define CIFS_MAGIC_NUMBER 0xFF534D42 +# define CIFS_MAGIC_NUMBER 0xFF534D42 #endif #ifndef TFD_TIMER_CANCEL_ON_SET -#define TFD_TIMER_CANCEL_ON_SET (1 << 1) +# define TFD_TIMER_CANCEL_ON_SET (1 << 1) #endif #ifndef SO_REUSEPORT -#define SO_REUSEPORT 15 +# define SO_REUSEPORT 15 #endif #ifndef EVIOCREVOKE -#define EVIOCREVOKE _IOW('E', 0x91, int) +# define EVIOCREVOKE _IOW('E', 0x91, int) #endif #ifndef DRM_IOCTL_SET_MASTER -#define DRM_IOCTL_SET_MASTER _IO('d', 0x1e) +# define DRM_IOCTL_SET_MASTER _IO('d', 0x1e) #endif #ifndef DRM_IOCTL_DROP_MASTER -#define DRM_IOCTL_DROP_MASTER _IO('d', 0x1f) +# define DRM_IOCTL_DROP_MASTER _IO('d', 0x1f) +#endif + +#ifndef TMP_MAX +# define TMP_MAX 238328 #endif |