journal: add inotify watches by-fd instead of by-path

This is slightly nicer, since we actually watch the directories we opened and
enumerate. However, primarily this is preparation for adding support for
opening journal files by fd without specifying any path, to be added in a later
commit.
This commit is contained in:
Lennart Poettering 2016-04-25 00:18:27 +02:00
parent 4f4d6ee4be
commit 430fbf8e7f
3 changed files with 22 additions and 5 deletions

View File

@ -38,6 +38,7 @@
#include "mkdir.h"
#include "parse-util.h"
#include "path-util.h"
#include "stdio-util.h"
#include "string-util.h"
#include "strv.h"
#include "time-util.h"
@ -493,3 +494,17 @@ int get_files_in_directory(const char *path, char ***list) {
return n;
}
int inotify_add_watch_fd(int fd, int what, uint32_t mask) {
char path[strlen("/proc/self/fd/") + DECIMAL_STR_MAX(int) + 1];
int r;
/* This is like inotify_add_watch(), except that the file to watch is not referenced by a path, but by an fd */
xsprintf(path, "/proc/self/fd/%i", what);
r = inotify_add_watch(fd, path, mask);
if (r < 0)
return -errno;
return r;
}

View File

@ -72,3 +72,5 @@ union inotify_event_buffer {
struct inotify_event ev;
uint8_t raw[INOTIFY_EVENT_MAX];
};
int inotify_add_watch_fd(int fd, int what, uint32_t mask);

View File

@ -1420,10 +1420,10 @@ static int add_directory(sd_journal *j, const char *prefix, const char *dirname)
if (m->wd <= 0 && j->inotify_fd >= 0) {
m->wd = inotify_add_watch(j->inotify_fd, m->path,
IN_CREATE|IN_MOVED_TO|IN_MODIFY|IN_ATTRIB|IN_DELETE|
IN_DELETE_SELF|IN_MOVE_SELF|IN_UNMOUNT|IN_MOVED_FROM|
IN_ONLYDIR);
m->wd = inotify_add_watch_fd(j->inotify_fd, dirfd(d),
IN_CREATE|IN_MOVED_TO|IN_MODIFY|IN_ATTRIB|IN_DELETE|
IN_DELETE_SELF|IN_MOVE_SELF|IN_UNMOUNT|IN_MOVED_FROM|
IN_ONLYDIR);
if (m->wd > 0 && hashmap_put(j->directories_by_wd, INT_TO_PTR(m->wd), m) < 0)
inotify_rm_watch(j->inotify_fd, m->wd);
@ -1505,7 +1505,7 @@ static int add_root_directory(sd_journal *j, const char *p, bool missing_ok) {
if (m->wd <= 0 && j->inotify_fd >= 0) {
m->wd = inotify_add_watch(j->inotify_fd, m->path,
m->wd = inotify_add_watch_fd(j->inotify_fd, dirfd(d),
IN_CREATE|IN_MOVED_TO|IN_MODIFY|IN_ATTRIB|IN_DELETE|
IN_ONLYDIR);