ncd: add if module

blog_channels.txt

@@ -7,6 +7,7 @@ ncd_var 4
 ncd_list 4
 ncd_depend 4
 ncd_concat 4
+ncd_if 4
 ncd_net_backend_physical 4
 ncd_net_backend_badvpn 4
 ncd_net_dns 4

generated/blog_channel_ncd_if.h

@@ -0,0 +1,4 @@
+#ifdef BLOG_CURRENT_CHANNEL
+#undef BLOG_CURRENT_CHANNEL
+#endif
+#define BLOG_CURRENT_CHANNEL BLOG_CHANNEL_ncd_if

generated/blog_channels_defines.h

@@ -7,27 +7,28 @@
 #define BLOG_CHANNEL_ncd_list 6
 #define BLOG_CHANNEL_ncd_depend 7
 #define BLOG_CHANNEL_ncd_concat 8
-#define BLOG_CHANNEL_ncd_net_backend_physical 9
-#define BLOG_CHANNEL_ncd_net_backend_badvpn 10
-#define BLOG_CHANNEL_ncd_net_dns 11
-#define BLOG_CHANNEL_ncd_net_iptables 12
-#define BLOG_CHANNEL_ncd_net_ipv4_addr 13
-#define BLOG_CHANNEL_ncd_net_ipv4_dhcp 14
-#define BLOG_CHANNEL_ncd_net_ipv4_route 15
-#define BLOG_CHANNEL_StreamPeerIO 16
-#define BLOG_CHANNEL_DatagramPeerIO 17
-#define BLOG_CHANNEL_BReactor 18
-#define BLOG_CHANNEL_BSignal 19
-#define BLOG_CHANNEL_FragmentProtoAssembler 20
-#define BLOG_CHANNEL_BPredicate 21
-#define BLOG_CHANNEL_ServerConnection 22
-#define BLOG_CHANNEL_Listener 23
-#define BLOG_CHANNEL_DataProto 24
-#define BLOG_CHANNEL_FrameDecider 25
-#define BLOG_CHANNEL_BSocksClient 26
-#define BLOG_CHANNEL_BDHCPClientCore 27
-#define BLOG_CHANNEL_BDHCPClient 28
-#define BLOG_CHANNEL_NCDIfConfig 29
-#define BLOG_CHANNEL_BUnixSignal 30
-#define BLOG_CHANNEL_BProcess 31
-#define BLOG_NUM_CHANNELS 32
+#define BLOG_CHANNEL_ncd_if 9
+#define BLOG_CHANNEL_ncd_net_backend_physical 10
+#define BLOG_CHANNEL_ncd_net_backend_badvpn 11
+#define BLOG_CHANNEL_ncd_net_dns 12
+#define BLOG_CHANNEL_ncd_net_iptables 13
+#define BLOG_CHANNEL_ncd_net_ipv4_addr 14
+#define BLOG_CHANNEL_ncd_net_ipv4_dhcp 15
+#define BLOG_CHANNEL_ncd_net_ipv4_route 16
+#define BLOG_CHANNEL_StreamPeerIO 17
+#define BLOG_CHANNEL_DatagramPeerIO 18
+#define BLOG_CHANNEL_BReactor 19
+#define BLOG_CHANNEL_BSignal 20
+#define BLOG_CHANNEL_FragmentProtoAssembler 21
+#define BLOG_CHANNEL_BPredicate 22
+#define BLOG_CHANNEL_ServerConnection 23
+#define BLOG_CHANNEL_Listener 24
+#define BLOG_CHANNEL_DataProto 25
+#define BLOG_CHANNEL_FrameDecider 26
+#define BLOG_CHANNEL_BSocksClient 27
+#define BLOG_CHANNEL_BDHCPClientCore 28
+#define BLOG_CHANNEL_BDHCPClient 29
+#define BLOG_CHANNEL_NCDIfConfig 30
+#define BLOG_CHANNEL_BUnixSignal 31
+#define BLOG_CHANNEL_BProcess 32
+#define BLOG_NUM_CHANNELS 33

generated/blog_channels_list.h

@@ -7,6 +7,7 @@
 {.name = "ncd_list", .loglevel = 4},
 {.name = "ncd_depend", .loglevel = 4},
 {.name = "ncd_concat", .loglevel = 4},
+{.name = "ncd_if", .loglevel = 4},
 {.name = "ncd_net_backend_physical", .loglevel = 4},
 {.name = "ncd_net_backend_badvpn", .loglevel = 4},
 {.name = "ncd_net_dns", .loglevel = 4},

ncd/CMakeLists.txt

@@ -9,6 +9,7 @@ add_executable(badvpn-ncd
     modules/list.c
     modules/depend.c
     modules/concat.c
+    modules/if.c
     modules/net_backend_physical.c
     modules/net_backend_badvpn.c
     modules/net_dns.c

ncd/modules/if.c

@@ -0,0 +1,118 @@
+/**
+ * @file if.c
+ * @author Ambroz Bizjak <ambrop7@gmail.com>
+ * 
+ * @section LICENSE
+ * 
+ * This file is part of BadVPN.
+ * 
+ * BadVPN is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation.
+ * 
+ * BadVPN is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ * 
+ * @section DESCRIPTION
+ * 
+ * Conditional module.
+ * 
+ * Synopsis: if(string cond)
+ * Description: on initialization, transitions to UP state if cond equals "true", else
+ *      remains in the DOWN state indefinitely.
+ * 
+ * Synopsis: ifnot(string cond)
+ * Description: on initialization, transitions to UP state if cond does not equal "true", else
+ *      remains in the DOWN state indefinitely.
+ */
+
+#include <stdlib.h>
+#include <string.h>
+
+#include <ncd/NCDModule.h>
+
+#include <generated/blog_channel_ncd_if.h>
+
+#define ModuleLog(i, ...) NCDModuleInst_Backend_Log((i), BLOG_CURRENT_CHANNEL, __VA_ARGS__)
+
+struct instance {
+    NCDModuleInst *i;
+};
+
+static void * new_templ (NCDModuleInst *i, int not)
+{
+    // allocate instance
+    struct instance *o = malloc(sizeof(*o));
+    if (!o) {
+        ModuleLog(i, BLOG_ERROR, "failed to allocate instance");
+        goto fail0;
+    }
+    
+    // init arguments
+    o->i = i;
+    
+    // check arguments
+    NCDValue *arg;
+    if (!NCDValue_ListRead(i->args, 1, &arg)) {
+        ModuleLog(o->i, BLOG_ERROR, "wrong arity");
+        goto fail1;
+    }
+    if (NCDValue_Type(arg) != NCDVALUE_STRING) {
+        ModuleLog(o->i, BLOG_ERROR, "wrong type");
+        goto fail1;
+    }
+    
+    int c = !strcmp(NCDValue_StringValue(arg), "true");
+    if ((not && !c) || (!not && c)) {
+        NCDModuleInst_Backend_Event(o->i, NCDMODULE_EVENT_UP);
+    }
+    
+    return o;
+    
+fail1:
+    free(o);
+fail0:
+    return NULL;
+}
+
+static void * func_new (NCDModuleInst *i)
+{
+    return new_templ(i, 0);
+}
+
+static void * func_new_not (NCDModuleInst *i)
+{
+    return new_templ(i, 1);
+}
+
+static void func_free (void *vo)
+{
+    struct instance *o = vo;
+    
+    // free instance
+    free(o);
+}
+
+static const struct NCDModule modules[] = {
+    {
+        .type = "if",
+        .func_new = func_new,
+        .func_free = func_free
+    }, {
+        .type = "ifnot",
+        .func_new = func_new_not,
+        .func_free = func_free
+    }, {
+        .type = NULL
+    }
+};
+
+const struct NCDModuleGroup ncdmodule_if = {
+    .modules = modules
+};

ncd/modules/modules.h

@@ -31,6 +31,7 @@ extern const struct NCDModuleGroup ncdmodule_var;
 extern const struct NCDModuleGroup ncdmodule_list;
 extern const struct NCDModuleGroup ncdmodule_depend;
 extern const struct NCDModuleGroup ncdmodule_concat;
+extern const struct NCDModuleGroup ncdmodule_if;
 extern const struct NCDModuleGroup ncdmodule_net_backend_physical;
 extern const struct NCDModuleGroup ncdmodule_net_backend_badvpn;
 extern const struct NCDModuleGroup ncdmodule_net_dns;
@@ -44,6 +45,7 @@ static const struct NCDModuleGroup *ncd_modules[] = {
     &ncdmodule_list,
     &ncdmodule_depend,
     &ncdmodule_concat,
+    &ncdmodule_if,
     &ncdmodule_net_backend_physical,
     &ncdmodule_net_backend_badvpn,
     &ncdmodule_net_dns,