journal: return -ECHILD after a fork

A few asserts are replaced with 'return -EINVAL'. I think that
assert should not be used to check argument in public functions.

Fields in struct sd_journal are rearranged to make it less
swiss-cheesy.
This commit is contained in:
Zbigniew Jędrzejewski-Szmek 2013-06-26 19:55:48 -04:00
parent daabe5491e
commit a65f06bb27
4 changed files with 93 additions and 17 deletions

5
TODO
View File

@ -126,7 +126,7 @@ Features:
* document systemd-journal-flush.service properly
* chane systemd-journal-flush into a service that stays around during
* change systemd-journal-flush into a service that stays around during
boot, and causes the journal to be moved back to /run on shutdown,
so that we don't keep /var busy. This needs to happen synchronously,
hence doing this via signals is not going to work.
@ -134,9 +134,6 @@ Features:
* allow implementation of InaccessibleDirectories=/ plus
ReadOnlyDirectories=... for whitelisting files for a service.
* libsystemd-journal:
- return ECHILD as soon as somebody tries to reuse a journal object across a fork()
* libsystemd-bus:
- default policy (allow uid == 0 and our own uid)
- enforce alignment of pointers passed in

View File

@ -131,6 +131,13 @@
can be rotated at any moment, and the opening of
specific files is inherently racy.</para>
<para><varname>sd_journal</varname> objects cannot be
used in the child after a fork. Functions which take a
journal object as an argument
(<function>sd_journal_next()</function> and others)
will return <constant>-ECHILD</constant> after a fork.
</para>
<para><function>sd_journal_close()</function> will
close the journal context allocated with
<function>sd_journal_open()</function> or

View File

@ -97,8 +97,6 @@ struct Directory {
};
struct sd_journal {
int flags;
char *path;
Hashmap *files;
@ -109,27 +107,29 @@ struct sd_journal {
JournalFile *current_file;
uint64_t current_field;
Hashmap *directories_by_path;
Hashmap *directories_by_wd;
int inotify_fd;
Match *level0, *level1, *level2;
pid_t original_pid;
int inotify_fd;
unsigned current_invalidate_counter, last_invalidate_counter;
usec_t last_process_usec;
char *unique_field;
JournalFile *unique_file;
uint64_t unique_offset;
int flags;
bool on_network;
bool no_new_files;
size_t data_threshold;
Set *errors;
Hashmap *directories_by_path;
Hashmap *directories_by_wd;
usec_t last_process_usec;
Set *errors;
};
char *journal_make_match_string(sd_journal *j);

View File

@ -50,6 +50,15 @@
#define DEFAULT_DATA_THRESHOLD (64*1024)
static bool journal_pid_changed(sd_journal *j) {
assert(j);
/* We don't support people creating a journal object and
* keeping it around over a fork(). Let's complain. */
return j->original_pid != getpid();
}
/* We return an error here only if we didn't manage to
memorize the real error. */
static int set_put_error(sd_journal *j, int r) {
@ -209,6 +218,8 @@ _public_ int sd_journal_add_match(sd_journal *j, const void *data, size_t size)
if (!j)
return -EINVAL;
if (journal_pid_changed(j))
return -ECHILD;
if (!data)
return -EINVAL;
@ -303,7 +314,10 @@ fail:
}
_public_ int sd_journal_add_conjunction(sd_journal *j) {
assert(j);
if (!j)
return -EINVAL;
if (journal_pid_changed(j))
return -ECHILD;
if (!j->level0)
return 0;
@ -321,7 +335,10 @@ _public_ int sd_journal_add_conjunction(sd_journal *j) {
}
_public_ int sd_journal_add_disjunction(sd_journal *j) {
assert(j);
if (!j)
return -EINVAL;
if (journal_pid_changed(j))
return -ECHILD;
if (!j->level0)
return 0;
@ -391,7 +408,6 @@ char *journal_make_match_string(sd_journal *j) {
}
_public_ void sd_journal_flush_matches(sd_journal *j) {
if (!j)
return;
@ -870,6 +886,8 @@ static int real_journal_next(sd_journal *j, direction_t direction) {
if (!j)
return -EINVAL;
if (journal_pid_changed(j))
return -ECHILD;
HASHMAP_FOREACH(f, j->files, i) {
bool found;
@ -922,6 +940,8 @@ static int real_journal_next_skip(sd_journal *j, direction_t direction, uint64_t
if (!j)
return -EINVAL;
if (journal_pid_changed(j))
return -ECHILD;
if (skip == 0) {
/* If this is not a discrete skip, then at least
@ -962,6 +982,8 @@ _public_ int sd_journal_get_cursor(sd_journal *j, char **cursor) {
if (!j)
return -EINVAL;
if (journal_pid_changed(j))
return -ECHILD;
if (!cursor)
return -EINVAL;
@ -1001,6 +1023,8 @@ _public_ int sd_journal_seek_cursor(sd_journal *j, const char *cursor) {
if (!j)
return -EINVAL;
if (journal_pid_changed(j))
return -ECHILD;
if (isempty(cursor))
return -EINVAL;
@ -1100,6 +1124,8 @@ _public_ int sd_journal_test_cursor(sd_journal *j, const char *cursor) {
if (!j)
return -EINVAL;
if (journal_pid_changed(j))
return -ECHILD;
if (isempty(cursor))
return -EINVAL;
@ -1178,6 +1204,8 @@ _public_ int sd_journal_test_cursor(sd_journal *j, const char *cursor) {
_public_ int sd_journal_seek_monotonic_usec(sd_journal *j, sd_id128_t boot_id, uint64_t usec) {
if (!j)
return -EINVAL;
if (journal_pid_changed(j))
return -ECHILD;
reset_location(j);
j->current_location.type = LOCATION_SEEK;
@ -1191,6 +1219,8 @@ _public_ int sd_journal_seek_monotonic_usec(sd_journal *j, sd_id128_t boot_id, u
_public_ int sd_journal_seek_realtime_usec(sd_journal *j, uint64_t usec) {
if (!j)
return -EINVAL;
if (journal_pid_changed(j))
return -ECHILD;
reset_location(j);
j->current_location.type = LOCATION_SEEK;
@ -1203,6 +1233,8 @@ _public_ int sd_journal_seek_realtime_usec(sd_journal *j, uint64_t usec) {
_public_ int sd_journal_seek_head(sd_journal *j) {
if (!j)
return -EINVAL;
if (journal_pid_changed(j))
return -ECHILD;
reset_location(j);
j->current_location.type = LOCATION_HEAD;
@ -1213,6 +1245,8 @@ _public_ int sd_journal_seek_head(sd_journal *j) {
_public_ int sd_journal_seek_tail(sd_journal *j) {
if (!j)
return -EINVAL;
if (journal_pid_changed(j))
return -ECHILD;
reset_location(j);
j->current_location.type = LOCATION_TAIL;
@ -1651,6 +1685,7 @@ static sd_journal *journal_new(int flags, const char *path) {
if (!j)
return NULL;
j->original_pid = getpid();
j->inotify_fd = -1;
j->flags = flags;
j->data_threshold = DEFAULT_DATA_THRESHOLD;
@ -1812,6 +1847,8 @@ _public_ int sd_journal_get_realtime_usec(sd_journal *j, uint64_t *ret) {
if (!j)
return -EINVAL;
if (journal_pid_changed(j))
return -ECHILD;
if (!ret)
return -EINVAL;
@ -1838,6 +1875,8 @@ _public_ int sd_journal_get_monotonic_usec(sd_journal *j, uint64_t *ret, sd_id12
if (!j)
return -EINVAL;
if (journal_pid_changed(j))
return -ECHILD;
f = j->current_file;
if (!f)
@ -1904,6 +1943,8 @@ _public_ int sd_journal_get_data(sd_journal *j, const char *field, const void **
if (!j)
return -EINVAL;
if (journal_pid_changed(j))
return -ECHILD;
if (!field)
return -EINVAL;
if (!data)
@ -2030,6 +2071,8 @@ _public_ int sd_journal_enumerate_data(sd_journal *j, const void **data, size_t
if (!j)
return -EINVAL;
if (journal_pid_changed(j))
return -ECHILD;
if (!data)
return -EINVAL;
if (!size)
@ -2080,6 +2123,8 @@ _public_ int sd_journal_get_fd(sd_journal *j) {
if (!j)
return -EINVAL;
if (journal_pid_changed(j))
return -ECHILD;
if (j->inotify_fd >= 0)
return j->inotify_fd;
@ -2107,6 +2152,8 @@ _public_ int sd_journal_get_events(sd_journal *j) {
if (!j)
return -EINVAL;
if (journal_pid_changed(j))
return -ECHILD;
fd = sd_journal_get_fd(j);
if (fd < 0)
@ -2120,6 +2167,8 @@ _public_ int sd_journal_get_timeout(sd_journal *j, uint64_t *timeout_usec) {
if (!j)
return -EINVAL;
if (journal_pid_changed(j))
return -ECHILD;
if (!timeout_usec)
return -EINVAL;
@ -2220,6 +2269,8 @@ _public_ int sd_journal_process(sd_journal *j) {
if (!j)
return -EINVAL;
if (journal_pid_changed(j))
return -ECHILD;
j->last_process_usec = now(CLOCK_MONOTONIC);
@ -2258,7 +2309,10 @@ _public_ int sd_journal_wait(sd_journal *j, uint64_t timeout_usec) {
int r;
uint64_t t;
assert(j);
if (!j)
return -EINVAL;
if (journal_pid_changed(j))
return -ECHILD;
if (j->inotify_fd < 0) {
@ -2307,6 +2361,8 @@ _public_ int sd_journal_get_cutoff_realtime_usec(sd_journal *j, uint64_t *from,
if (!j)
return -EINVAL;
if (journal_pid_changed(j))
return -ECHILD;
if (!from && !to)
return -EINVAL;
if (from == to)
@ -2348,6 +2404,8 @@ _public_ int sd_journal_get_cutoff_monotonic_usec(sd_journal *j, sd_id128_t boot
if (!j)
return -EINVAL;
if (journal_pid_changed(j))
return -ECHILD;
if (!from && !to)
return -EINVAL;
if (from == to)
@ -2405,6 +2463,8 @@ _public_ int sd_journal_get_usage(sd_journal *j, uint64_t *bytes) {
if (!j)
return -EINVAL;
if (journal_pid_changed(j))
return -ECHILD;
if (!bytes)
return -EINVAL;
@ -2426,6 +2486,8 @@ _public_ int sd_journal_query_unique(sd_journal *j, const char *field) {
if (!j)
return -EINVAL;
if (journal_pid_changed(j))
return -ECHILD;
if (isempty(field))
return -EINVAL;
if (!field_is_valid(field))
@ -2450,6 +2512,8 @@ _public_ int sd_journal_enumerate_unique(sd_journal *j, const void **data, size_
if (!j)
return -EINVAL;
if (journal_pid_changed(j))
return -ECHILD;
if (!data)
return -EINVAL;
if (!l)
@ -2562,6 +2626,8 @@ _public_ void sd_journal_restart_unique(sd_journal *j) {
_public_ int sd_journal_reliable_fd(sd_journal *j) {
if (!j)
return -EINVAL;
if (journal_pid_changed(j))
return -ECHILD;
return !j->on_network;
}
@ -2595,6 +2661,8 @@ _public_ int sd_journal_get_catalog(sd_journal *j, char **ret) {
if (!j)
return -EINVAL;
if (journal_pid_changed(j))
return -ECHILD;
if (!ret)
return -EINVAL;
@ -2632,6 +2700,8 @@ _public_ int sd_journal_get_catalog_for_message_id(sd_id128_t id, char **ret) {
_public_ int sd_journal_set_data_threshold(sd_journal *j, size_t sz) {
if (!j)
return -EINVAL;
if (journal_pid_changed(j))
return -ECHILD;
j->data_threshold = sz;
return 0;
@ -2640,6 +2710,8 @@ _public_ int sd_journal_set_data_threshold(sd_journal *j, size_t sz) {
_public_ int sd_journal_get_data_threshold(sd_journal *j, size_t *sz) {
if (!j)
return -EINVAL;
if (journal_pid_changed(j))
return -ECHILD;
if (!sz)
return -EINVAL;