-/* dnsmasq is Copyright (c) 2000-2014 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2015 Simon Kelley
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
#ifdef HAVE_INOTIFY
#include <sys/inotify.h>
-
-#ifdef HAVE_DHCP
-static void check_for_dhcp_inotify(struct inotify_event *in, time_t now);
-#endif
-
+#include <sys/param.h> /* For MAXSYMLINKS */
/* the strategy is to set a inotify on the directories containing
resolv files, for any files in the directory which are close-write
static char *inotify_buffer;
#define INOTIFY_SZ (sizeof(struct inotify_event) + NAME_MAX + 1)
+/* If path is a symbolic link, return the path it
+ points to, made absolute if relative.
+ If path doesn't exist or is not a symlink, return NULL.
+ Return value is malloc'ed */
+static char *my_readlink(char *path)
+{
+ ssize_t rc;
+ size_t size = 64;
+ char *buf;
+
+ while (1)
+ {
+ buf = safe_malloc(size);
+ rc = readlink(path, buf, size);
+
+ if (rc == -1)
+ {
+ /* Not link or doesn't exist. */
+ if (errno == EINVAL || errno == ENOENT)
+ return NULL;
+ else
+ die(_("cannot access path %s: %s"), path, EC_MISC);
+ }
+ else if (rc < size-1)
+ {
+ char *d;
+
+ buf[rc] = 0;
+ if (buf[0] != '/' && ((d = strrchr(path, '/'))))
+ {
+ /* Add path to relative link */
+ char *new_buf = safe_malloc((d - path) + strlen(buf) + 2);
+ *(d+1) = 0;
+ strcpy(new_buf, path);
+ strcat(new_buf, buf);
+ free(buf);
+ buf = new_buf;
+ }
+ return buf;
+ }
+
+ /* Buffer too small, increase and retry */
+ size += 64;
+ free(buf);
+ }
+}
+
void inotify_dnsmasq_init()
{
struct resolvc *res;
-
inotify_buffer = safe_malloc(INOTIFY_SZ);
daemon->inotifyfd = inotify_init1(IN_NONBLOCK | IN_CLOEXEC);
for (res = daemon->resolv_files; res; res = res->next)
{
- char *d = NULL, *path;
-
- if (!(path = realpath(res->name, NULL)))
+ char *d, *new_path, *path = safe_malloc(strlen(res->name) + 1);
+ int links = MAXSYMLINKS;
+
+ strcpy(path, res->name);
+
+ /* Follow symlinks until we reach a non-symlink, or a non-existant file. */
+ while ((new_path = my_readlink(path)))
{
- /* realpath will fail if the file doesn't exist, but
- dnsmasq copes with missing files, so fall back
- and assume that symlinks are not in use in that case. */
- if (errno == ENOENT)
- path = res->name;
- else
- die(_("cannot cannonicalise resolv-file %s: %s"), res->name, EC_MISC);
+ if (links-- == 0)
+ die(_("too many symlinks following %s"), res->name, EC_MISC);
+ free(path);
+ path = new_path;
}
-
+
+ res->wd = -1;
+
if ((d = strrchr(path, '/')))
{
*d = 0; /* make path just directory */
if (res->wd == -1 && errno == ENOENT)
die(_("directory %s for resolv-file is missing, cannot poll"), res->name, EC_MISC);
-
- if (res->wd == -1)
- die(_("failed to create inotify for %s: %s"), res->name, EC_MISC);
- }
+ }
+
+ if (res->wd == -1)
+ die(_("failed to create inotify for %s: %s"), res->name, EC_MISC);
+
}
}
-int inotify_check(time_t now)
+
+/* initialisation for dynamic-dir. Set inotify watch for each directory, and read pre-existing files */
+void set_dynamic_inotify(int flag, int total_size, struct crec **rhash, int revhashsz)
{
- int hit = 0;
+ struct hostsfile *ah;
- while (1)
+ for (ah = daemon->dynamic_dirs; ah; ah = ah->next)
{
- int rc;
- char *p;
- struct resolvc *res;
- struct inotify_event *in;
-
- while ((rc = read(daemon->inotifyfd, inotify_buffer, INOTIFY_SZ)) == -1 && errno == EINTR);
-
- if (rc <= 0)
- break;
-
- for (p = inotify_buffer; rc - (p - inotify_buffer) >= (int)sizeof(struct inotify_event); p += sizeof(struct inotify_event) + in->len)
+ DIR *dir_stream = NULL;
+ struct dirent *ent;
+ struct stat buf;
+
+ if (!(ah->flags & flag))
+ continue;
+
+ if (stat(ah->fname, &buf) == -1 || !(S_ISDIR(buf.st_mode)))
{
- in = (struct inotify_event*)p;
-
- for (res = daemon->resolv_files; res; res = res->next)
- if (res->wd == in->wd && in->len != 0 && strcmp(res->file, in->name) == 0)
- hit = 1;
-
-#ifdef HAVE_DHCP
- if (daemon->dhcp || daemon->doing_dhcp6)
- check_for_dhcp_inotify(in, now);
-#endif
+ my_syslog(LOG_ERR, _("bad dynamic directory %s: %s"),
+ ah->fname, strerror(errno));
+ continue;
}
- }
- return hit;
-}
-
-#ifdef HAVE_DHCP
-/* initialisation for dhcp-hostdir. Set inotify watch for each directory, and read pre-existing files */
-void set_dhcp_inotify(void)
-{
- struct hostsfile *ah;
-
- for (ah = daemon->inotify_hosts; ah; ah = ah->next)
- {
- DIR *dir_stream = NULL;
- struct dirent *ent;
- struct stat buf;
-
- if (stat(ah->fname, &buf) == -1 || !(S_ISDIR(buf.st_mode)))
- {
- my_syslog(LOG_ERR, _("bad directory in dhcp-hostsdir %s"), ah->fname);
- continue;
- }
-
+
if (!(ah->flags & AH_WD_DONE))
{
ah->wd = inotify_add_watch(daemon->inotifyfd, ah->fname, IN_CLOSE_WRITE | IN_MOVED_TO);
ah->flags |= AH_WD_DONE;
}
- /* Read contents of dir _after_ calling add_watch, in the ho[e of avoiding
+
+ /* Read contents of dir _after_ calling add_watch, in the hope of avoiding
a race which misses files being added as we start */
if (ah->wd == -1 || !(dir_stream = opendir(ah->fname)))
{
- my_syslog(LOG_ERR, _("failed to create inotify for %s"), ah->fname);
+ my_syslog(LOG_ERR, _("failed to create inotify for %s: %s"),
+ ah->fname, strerror(errno));
continue;
}
/* ignore non-regular files */
if (stat(path, &buf) != -1 && S_ISREG(buf.st_mode))
- option_read_hostsfile(path);
-
+ {
+ if (ah->flags & AH_HOSTS)
+ total_size = read_hostsfile(path, ah->index, total_size, rhash, revhashsz);
+#ifdef HAVE_DHCP
+ else if (ah->flags & (AH_DHCP_HST | AH_DHCP_OPT))
+ option_read_dynfile(path, ah->flags);
+#endif
+ }
+
free(path);
}
}
}
}
-static void check_for_dhcp_inotify(struct inotify_event *in, time_t now)
+int inotify_check(time_t now)
{
+ int hit = 0;
struct hostsfile *ah;
- /* ignore emacs backups and dotfiles */
- if (in->len == 0 ||
- in->name[in->len - 1] == '~' ||
- (in->name[0] == '#' && in->name[in->len - 1] == '#') ||
- in->name[0] == '.')
- return;
-
- for (ah = daemon->inotify_hosts; ah; ah = ah->next)
- if (ah->wd == in->wd)
- {
- size_t lendir = strlen(ah->fname);
- char *path;
-
- if ((path = whine_malloc(lendir + in->len + 2)))
- {
- strcpy(path, ah->fname);
- strcat(path, "/");
- strcat(path, in->name);
-
- if (option_read_hostsfile(path))
+ while (1)
+ {
+ int rc;
+ char *p;
+ struct resolvc *res;
+ struct inotify_event *in;
+
+ while ((rc = read(daemon->inotifyfd, inotify_buffer, INOTIFY_SZ)) == -1 && errno == EINTR);
+
+ if (rc <= 0)
+ break;
+
+ for (p = inotify_buffer; rc - (p - inotify_buffer) >= (int)sizeof(struct inotify_event); p += sizeof(struct inotify_event) + in->len)
+ {
+ in = (struct inotify_event*)p;
+
+ for (res = daemon->resolv_files; res; res = res->next)
+ if (res->wd == in->wd && in->len != 0 && strcmp(res->file, in->name) == 0)
+ hit = 1;
+
+ /* ignore emacs backups and dotfiles */
+ if (in->len == 0 ||
+ in->name[in->len - 1] == '~' ||
+ (in->name[0] == '#' && in->name[in->len - 1] == '#') ||
+ in->name[0] == '.')
+ continue;
+
+ for (ah = daemon->dynamic_dirs; ah; ah = ah->next)
+ if (ah->wd == in->wd)
{
- /* Propogate the consequences of loading a new dhcp-host */
- dhcp_update_configs(daemon->dhcp_conf);
- lease_update_from_configs();
- lease_update_file(now);
- lease_update_dns(1);
+ size_t lendir = strlen(ah->fname);
+ char *path;
+
+ if ((path = whine_malloc(lendir + in->len + 2)))
+ {
+ strcpy(path, ah->fname);
+ strcat(path, "/");
+ strcat(path, in->name);
+
+ my_syslog(LOG_INFO, _("inotify, new or changed file %s"), path);
+
+ if (ah->flags & AH_HOSTS)
+ {
+ read_hostsfile(path, ah->index, 0, NULL, 0);
+#ifdef HAVE_DHCP
+ if (daemon->dhcp || daemon->doing_dhcp6)
+ {
+ /* Propogate the consequences of loading a new dhcp-host */
+ dhcp_update_configs(daemon->dhcp_conf);
+ lease_update_from_configs();
+ lease_update_file(now);
+ lease_update_dns(1);
+ }
+#endif
+ }
+#ifdef HAVE_DHCP
+ else if (ah->flags & AH_DHCP_HST)
+ {
+ if (option_read_dynfile(path, AH_DHCP_HST))
+ {
+ /* Propogate the consequences of loading a new dhcp-host */
+ dhcp_update_configs(daemon->dhcp_conf);
+ lease_update_from_configs();
+ lease_update_file(now);
+ lease_update_dns(1);
+ }
+ }
+ else if (ah->flags & AH_DHCP_OPT)
+ option_read_dynfile(path, AH_DHCP_OPT);
+#endif
+
+ free(path);
+ }
}
-
- free(path);
- }
-
- return;
- }
+ }
+ }
+ return hit;
}
-#endif /* DHCP */
-
#endif /* INOTIFY */
projects / people / ms / dnsmasq.git / blobdiff