statefiles: create helper functions to write leases

Break statesfiles_write_state() into smaller parts, making it easier to
read and understand the logic of each part.

Signed-off-by: David Härdeman <[email protected]>
Link: https://github.com/openwrt/odhcpd/pull/302
Signed-off-by: Álvaro Fernández Rojas <[email protected]>

diff --git a/src/statefiles.c b/src/statefiles.c
index e90e7c6cdc2eddda4a2e8b800ae4b553615b88a1..86a36e59db4f415204317fecfd02450143ad6af7 100644 (file)
--- a/src/statefiles.c
+++ b/src/statefiles.c
@@ -93,6 +93,8 @@ struct write_ctxt {
        md5_ctx_t md5;
        struct dhcpv6_lease *c;
        struct interface *iface;
+       time_t now; // CLOCK_MONOTONIC
+       time_t wall_time;
        char *buf;
        int buf_len;
        int buf_idx;
@@ -221,13 +223,88 @@ err:
        close(fd);
 }
 
+static void statefiles_write_dhcpv6_lease(struct write_ctxt *ctxt)
+{
+       char duidbuf[DUID_HEXSTRLEN];
+
+       odhcpd_hexlify(duidbuf, ctxt->c->clid_data, ctxt->c->clid_len);
+
+       /* iface DUID iaid hostname lifetime assigned_host_id length [addrs...] */
+       ctxt->buf_idx = snprintf(ctxt->buf, ctxt->buf_len, "# %s %s %x %s%s %"PRId64" ",
+                                ctxt->iface->ifname, duidbuf, ntohl(ctxt->c->iaid),
+                                (ctxt->c->flags & OAF_BROKEN_HOSTNAME) ? "broken\\x20" : "",
+                                (ctxt->c->hostname ? ctxt->c->hostname : "-"),
+                                (ctxt->c->valid_until > ctxt->now ?
+                                 (int64_t)(ctxt->c->valid_until - ctxt->now + ctxt->wall_time) :
+                                 (INFINITE_VALID(ctxt->c->valid_until) ? -1 : 0)));
+
+       if (ctxt->c->flags & OAF_DHCPV6_NA)
+               ctxt->buf_idx += snprintf(ctxt->buf + ctxt->buf_idx, ctxt->buf_len - ctxt->buf_idx,
+                                         "%" PRIx64" %u ", ctxt->c->assigned_host_id, (unsigned)ctxt->c->length);
+       else
+               ctxt->buf_idx += snprintf(ctxt->buf + ctxt->buf_idx, ctxt->buf_len - ctxt->buf_idx,
+                                         "%" PRIx32" %u ", ctxt->c->assigned_subnet_id, (unsigned)ctxt->c->length);
+
+       if (INFINITE_VALID(ctxt->c->valid_until) || ctxt->c->valid_until > ctxt->now)
+               dhcpv6_ia_enum_addrs(ctxt->iface, ctxt->c, ctxt->now,
+                                    dhcpv6_write_ia_addr, ctxt);
+
+       ctxt->buf[ctxt->buf_idx - 1] = '\n';
+       fwrite(ctxt->buf, 1, ctxt->buf_idx, ctxt->fp);
+}
+
+static void statefiles_write_dhcpv4_lease(struct write_ctxt *ctxt, struct dhcpv4_lease *c)
+{
+       char ipbuf[INET6_ADDRSTRLEN];
+       char duidbuf[16];
+       odhcpd_hexlify(duidbuf, c->hwaddr, sizeof(c->hwaddr));
+
+       /* iface DUID iaid hostname lifetime assigned length [addrs...] */
+       ctxt->buf_idx = snprintf(ctxt->buf, ctxt->buf_len, "# %s %s ipv4 %s%s %"PRId64" %x 32 ",
+                                ctxt->iface->ifname, duidbuf,
+                                (c->flags & OAF_BROKEN_HOSTNAME) ? "broken\\x20" : "",
+                                (c->hostname ? c->hostname : "-"),
+                                (c->valid_until > ctxt->now ?
+                                 (int64_t)(c->valid_until - ctxt->now + ctxt->wall_time) :
+                                 (INFINITE_VALID(c->valid_until) ? -1 : 0)),
+                                ntohl(c->addr));
+
+       struct in_addr addr = {.s_addr = c->addr};
+       inet_ntop(AF_INET, &addr, ipbuf, sizeof(ipbuf) - 1);
+
+       if (c->hostname && !(c->flags & OAF_BROKEN_HOSTNAME)) {
+               fputs(ipbuf, ctxt->fp);
+
+               char b[256];
+               if (dn_expand(ctxt->iface->search,
+                             ctxt->iface->search + ctxt->iface->search_len,
+                             ctxt->iface->search, b, sizeof(b)) > 0)
+                       fprintf(ctxt->fp, "\t%s.%s", c->hostname, b);
+
+               fprintf(ctxt->fp, "\t%s\n", c->hostname);
+               md5_hash(ipbuf, strlen(ipbuf), &ctxt->md5);
+               md5_hash(c->hostname, strlen(c->hostname), &ctxt->md5);
+       }
+
+       ctxt->buf_idx += snprintf(ctxt->buf + ctxt->buf_idx,
+                                 ctxt->buf_len - ctxt->buf_idx,
+                                 "%s/32 ", ipbuf);
+       ctxt->buf[ctxt->buf_idx - 1] = '\n';
+       fwrite(ctxt->buf, 1, ctxt->buf_idx, ctxt->fp);
+}
+
 static bool statefiles_write_state(time_t now)
 {
-       struct write_ctxt ctxt;
+       char leasebuf[512];
+       struct write_ctxt ctxt = {
+               .fp = NULL,
+               .buf = leasebuf,
+               .buf_len = sizeof(leasebuf),
+               .now = now,
+               .wall_time = time(NULL),
+       };
        size_t tmp_statefile_strlen;
        char *tmp_statefile;
-       time_t wall_time = time(NULL);
-       char leasebuf[512];
        uint8_t newmd5[16];
        int fd;
 
@@ -252,89 +329,21 @@ static bool statefiles_write_state(time_t now)
        if (!ctxt.fp)
                goto err;
 
-       ctxt.buf = leasebuf;
-       ctxt.buf_len = sizeof(leasebuf);
        md5_begin(&ctxt.md5);
 
        avl_for_each_element(&interfaces, ctxt.iface, avl) {
                if (ctxt.iface->dhcpv6 == MODE_SERVER) {
-                       list_for_each_entry(ctxt.c, &ctxt.iface->ia_assignments, head) {
-                               if (!(ctxt.c->flags & OAF_BOUND))
-                                       continue;
-
-                               char duidbuf[DUID_HEXSTRLEN];
-
-                               odhcpd_hexlify(duidbuf, ctxt.c->clid_data, ctxt.c->clid_len);
-
-                               /* iface DUID iaid hostname lifetime assigned_host_id length [addrs...] */
-                               ctxt.buf_idx = snprintf(ctxt.buf, ctxt.buf_len, "# %s %s %x %s%s %"PRId64" ",
-                                                       ctxt.iface->ifname, duidbuf, ntohl(ctxt.c->iaid),
-                                                       (ctxt.c->flags & OAF_BROKEN_HOSTNAME) ? "broken\\x20" : "",
-                                                       (ctxt.c->hostname ? ctxt.c->hostname : "-"),
-                                                       (ctxt.c->valid_until > now ?
-                                                               (int64_t)(ctxt.c->valid_until - now + wall_time) :
-                                                               (INFINITE_VALID(ctxt.c->valid_until) ? -1 : 0)));
-
-                               if (ctxt.c->flags & OAF_DHCPV6_NA)
-                                       ctxt.buf_idx += snprintf(ctxt.buf + ctxt.buf_idx, ctxt.buf_len - ctxt.buf_idx,
-                                                                "%" PRIx64" %u ", ctxt.c->assigned_host_id, (unsigned)ctxt.c->length);
-                               else
-                                       ctxt.buf_idx += snprintf(ctxt.buf + ctxt.buf_idx, ctxt.buf_len - ctxt.buf_idx,
-                                                                "%" PRIx32" %u ", ctxt.c->assigned_subnet_id, (unsigned)ctxt.c->length);
-
-                               if (INFINITE_VALID(ctxt.c->valid_until) || ctxt.c->valid_until > now)
-                                       dhcpv6_ia_enum_addrs(ctxt.iface, ctxt.c, now,
-                                                               dhcpv6_write_ia_addr, &ctxt);
-
-                               ctxt.buf[ctxt.buf_idx - 1] = '\n';
-                               fwrite(ctxt.buf, 1, ctxt.buf_idx, ctxt.fp);
-                       }
+                       list_for_each_entry(ctxt.c, &ctxt.iface->ia_assignments, head)
+                               if (ctxt.c->flags & OAF_BOUND)
+                                       statefiles_write_dhcpv6_lease(&ctxt);
                }
 
                if (ctxt.iface->dhcpv4 == MODE_SERVER) {
                        struct dhcpv4_lease *c;
 
-                       list_for_each_entry(c, &ctxt.iface->dhcpv4_leases, head) {
-                               if (!(c->flags & OAF_BOUND))
-                                       continue;
-
-                               char ipbuf[INET6_ADDRSTRLEN];
-                               char duidbuf[16];
-                               odhcpd_hexlify(duidbuf, c->hwaddr, sizeof(c->hwaddr));
-
-                               /* iface DUID iaid hostname lifetime assigned length [addrs...] */
-                               ctxt.buf_idx = snprintf(ctxt.buf, ctxt.buf_len, "# %s %s ipv4 %s%s %"PRId64" %x 32 ",
-                                                       ctxt.iface->ifname, duidbuf,
-                                                       (c->flags & OAF_BROKEN_HOSTNAME) ? "broken\\x20" : "",
-                                                       (c->hostname ? c->hostname : "-"),
-                                                       (c->valid_until > now ?
-                                                               (int64_t)(c->valid_until - now + wall_time) :
-                                                               (INFINITE_VALID(c->valid_until) ? -1 : 0)),
-                                                       ntohl(c->addr));
-
-                               struct in_addr addr = {.s_addr = c->addr};
-                               inet_ntop(AF_INET, &addr, ipbuf, sizeof(ipbuf) - 1);
-
-                               if (c->hostname && !(c->flags & OAF_BROKEN_HOSTNAME)) {
-                                       fputs(ipbuf, ctxt.fp);
-
-                                       char b[256];
-                                       if (dn_expand(ctxt.iface->search,
-                                                       ctxt.iface->search + ctxt.iface->search_len,
-                                                       ctxt.iface->search, b, sizeof(b)) > 0)
-                                               fprintf(ctxt.fp, "\t%s.%s", c->hostname, b);
-
-                                       fprintf(ctxt.fp, "\t%s\n", c->hostname);
-                                       md5_hash(ipbuf, strlen(ipbuf), &ctxt.md5);
-                                       md5_hash(c->hostname, strlen(c->hostname), &ctxt.md5);
-                               }
-
-                               ctxt.buf_idx += snprintf(ctxt.buf + ctxt.buf_idx,
-                                                               ctxt.buf_len - ctxt.buf_idx,
-                                                               "%s/32 ", ipbuf);
-                               ctxt.buf[ctxt.buf_idx - 1] = '\n';
-                               fwrite(ctxt.buf, 1, ctxt.buf_idx, ctxt.fp);
-                       }
+                       list_for_each_entry(c, &ctxt.iface->dhcpv4_leases, head)
+                               if (c->flags & OAF_BOUND)
+                                       statefiles_write_dhcpv4_lease(&ctxt, c);
                }
        }