lib: Abstract parsing of distribute lists

Abstract the parsing of distribute lists so that we
don't have as much cut-n-paste code.

This is a setup commit for future work.  In effect
current distribute-list handling is all kinds of messed up

a) eigrp and babel both attempt to use distribute-lists, they just plain
don't work.
b) `distribute-list` is only sent to rip.  `ipv6 distribute-list`
is sent to ripngd.  If you use `distribute-list` under `router ripng`
it sends the command to rip but ripd is in the wrong mode and it
never works.
c) Should ripngd care about v4 and v6 specific distribute-lists?
This dichotomy was added for babel but babel has been broke
about this since day 1( see a ).

All in all we need to unwind this whole mess.  Make distribute-list
commands specific to the daemons( so that we can be in the right
sub-mode ).  But the parsing is going to be the same across all
daemons.  So let's provide that functionality in `lib/distribute.c`

Signed-off-by: Donald Sharp <sharpd@nvidia.com>

diff --git a/lib/distribute.c b/lib/distribute.c
index 60bd0a47bb0c00f2f7f01da7b004a5834ff35c2e..bc402798d68391f67cefdc1474e3441a3d813c64 100644 (file)
--- a/lib/distribute.c
+++ b/lib/distribute.c
@@ -240,6 +240,40 @@ static int distribute_list_prefix_unset(struct distribute_ctx *ctx,
        return 1;
 }
 
+static enum distribute_type distribute_direction(const char *dir, bool v4)
+{
+       if (dir[0] == 'i') {
+               if (v4)
+                       return DISTRIBUTE_V4_IN;
+               else
+                       return DISTRIBUTE_V6_IN;
+       } else if (dir[0] == 'o') {
+               if (v4)
+                       return DISTRIBUTE_V4_OUT;
+               else
+                       return DISTRIBUTE_V6_OUT;
+       }
+
+       assert(!"Expecting in or out only, fix your code");
+
+       __builtin_unreachable();
+}
+
+static int distribute_list_parser(bool prefix, bool v4, const char *dir,
+                                 const char *list, const char *ifname)
+{
+       enum distribute_type type = distribute_direction(dir, v4);
+       struct distribute_ctx *ctx = listnode_head(dist_ctx_list);
+
+       void (*distfn)(struct distribute_ctx *, const char *,
+                      enum distribute_type, const char *) =
+               prefix ? &distribute_list_prefix_set : &distribute_list_set;
+
+       distfn(ctx, ifname, type, list);
+
+       return CMD_SUCCESS;
+}
+
 DEFUN (distribute_list,
        distribute_list_cmd,
        "distribute-list [prefix] WORD <in|out> [WORD]",
@@ -250,28 +284,14 @@ DEFUN (distribute_list,
        "Filter outgoing routing updates\n"
        "Interface name\n")
 {
+       const char *ifname = NULL;
        int prefix = (argv[1]->type == WORD_TKN) ? 1 : 0;
-       /* Check of distribute list type. */
-       enum distribute_type type = argv[2 + prefix]->arg[0] == 'i'
-                                           ? DISTRIBUTE_V4_IN
-                                           : DISTRIBUTE_V4_OUT;
 
-       /* Set appropriate function call */
-       void (*distfn)(struct distribute_ctx *, const char *,
-                      enum distribute_type, const char *) =
-               prefix ? &distribute_list_prefix_set : &distribute_list_set;
-       struct distribute_ctx *ctx =
-               (struct distribute_ctx *)listnode_head(dist_ctx_list);
-
-       /* if interface is present, get name */
-       const char *ifname = NULL;
        if (argv[argc - 1]->type == VARIABLE_TKN)
                ifname = argv[argc - 1]->arg;
 
-       /* Get interface name corresponding distribute list. */
-       distfn(ctx, ifname, type, argv[1 + prefix]->arg);
-
-       return CMD_SUCCESS;
+       return distribute_list_parser(prefix, true, argv[2 + prefix]->arg,
+                                     argv[1 + prefix]->arg, ifname);
 }
 
 DEFUN (ipv6_distribute_list,
@@ -285,25 +305,33 @@ DEFUN (ipv6_distribute_list,
        "Filter outgoing routing updates\n"
        "Interface name\n")
 {
+       const char *ifname = NULL;
        int prefix = (argv[2]->type == WORD_TKN) ? 1 : 0;
-       /* Check of distribute list type. */
-       enum distribute_type type = argv[3 + prefix]->arg[0] == 'i'
-                                           ? DISTRIBUTE_V6_IN
-                                           : DISTRIBUTE_V6_OUT;
-
-       /* Set appropriate function call */
-       void (*distfn)(struct distribute_ctx *, const char *,
-                      enum distribute_type, const char *) =
-               prefix ? &distribute_list_prefix_set : &distribute_list_set;
-       struct distribute_ctx *ctx = listnode_head(dist_ctx_list);
 
-       /* if interface is present, get name */
-       const char *ifname = NULL;
        if (argv[argc - 1]->type == VARIABLE_TKN)
                ifname = argv[argc - 1]->arg;
 
-       /* Get interface name corresponding distribute list. */
-       distfn(ctx, ifname, type, argv[2 + prefix]->arg);
+       return distribute_list_parser(prefix, false, argv[3 + prefix]->arg,
+                                     argv[2 + prefix]->arg, ifname);
+}
+static int distribute_list_no_parser(struct vty *vty, bool prefix, bool v4,
+                                    const char *dir, const char *list,
+                                    const char *ifname)
+{
+       enum distribute_type type = distribute_direction(dir, v4);
+       struct distribute_ctx *ctx = listnode_head(dist_ctx_list);
+       int ret;
+
+       int (*distfn)(struct distribute_ctx *, const char *,
+                     enum distribute_type, const char *) =
+               prefix ? &distribute_list_prefix_unset : &distribute_list_unset;
+
+
+       ret = distfn(ctx, ifname, type, list);
+       if (!ret) {
+               vty_out(vty, "distribute list doesn't exist\n");
+               return CMD_WARNING_CONFIG_FAILED;
+       }
 
        return CMD_SUCCESS;
 }
@@ -319,31 +347,15 @@ DEFUN (no_distribute_list,
        "Filter outgoing routing updates\n"
        "Interface name\n")
 {
+       const char *ifname = NULL;
        int prefix = (argv[2]->type == WORD_TKN) ? 1 : 0;
-       int idx_alname = 2 + prefix;
-       int idx_disttype = idx_alname + 1;
-       enum distribute_type type =
-               argv[idx_disttype]->arg[0] == 'i' ?
-               DISTRIBUTE_V4_IN : DISTRIBUTE_V4_OUT;
 
-       /* Set appropriate function call */
-       int (*distfn)(struct distribute_ctx *, const char *,
-                      enum distribute_type, const char *) =
-               prefix ? &distribute_list_prefix_unset : &distribute_list_unset;
-       struct distribute_ctx *ctx = listnode_head(dist_ctx_list);
-
-       /* if interface is present, get name */
-       const char *ifname = NULL;
        if (argv[argc - 1]->type == VARIABLE_TKN)
                ifname = argv[argc - 1]->arg;
-       /* Get interface name corresponding distribute list. */
-       int ret = distfn(ctx, ifname, type, argv[2 + prefix]->arg);
 
-       if (!ret) {
-               vty_out(vty, "distribute list doesn't exist\n");
-               return CMD_WARNING_CONFIG_FAILED;
-       }
-       return CMD_SUCCESS;
+       return distribute_list_no_parser(vty, prefix, true,
+                                        argv[3 + prefix]->arg,
+                                        argv[2 + prefix]->arg, ifname);
 }
 
 DEFUN (no_ipv6_distribute_list,
@@ -358,33 +370,15 @@ DEFUN (no_ipv6_distribute_list,
        "Filter outgoing routing updates\n"
        "Interface name\n")
 {
-       int prefix = (argv[3]->type == WORD_TKN) ? 1 : 0;
-       int idx_alname = 3 + prefix;
-       int idx_disttype = idx_alname + 1;
-
-       enum distribute_type type =
-               argv[idx_disttype]->arg[0] == 'i' ?
-               DISTRIBUTE_V6_IN : DISTRIBUTE_V6_OUT;
-       struct distribute_ctx *ctx = listnode_head(dist_ctx_list);
-
-       /* Set appropriate function call */
-       int (*distfn)(struct distribute_ctx *, const char *,
-                      enum distribute_type, const char *) =
-               prefix ? &distribute_list_prefix_unset : &distribute_list_unset;
-
-       /* if interface is present, get name */
        const char *ifname = NULL;
+       int prefix = (argv[3]->type == WORD_TKN) ? 1 : 0;
 
        if (argv[argc - 1]->type == VARIABLE_TKN)
                ifname = argv[argc - 1]->arg;
-       /* Get interface name corresponding distribute list. */
-       int ret = distfn(ctx, ifname, type, argv[3 + prefix]->arg);
 
-       if (!ret) {
-               vty_out(vty, "distribute list doesn't exist\n");
-               return CMD_WARNING_CONFIG_FAILED;
-       }
-       return CMD_SUCCESS;
+       return distribute_list_no_parser(vty, prefix, false,
+                                        argv[4 + prefix]->arg,
+                                        argv[3 + prefix]->arg, ifname);
 }
 
 static int distribute_print(struct vty *vty, char *tab[], int is_prefix,