Merge commit 'a845651b' into thread-next

5 files changed, 124 insertions, 36 deletions

diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 7809fecd..0a758cff 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -134,21 +134,11 @@ docker_fedora-34-amd64:
     IMG_NAME: "fedora-34-amd64"
   <<: *docker_build
 
-docker_centos-7-amd64:
-  variables:
-    IMG_NAME: "centos-7-amd64"
-  <<: *docker_build
-
 docker_centos-8-amd64:
   variables:
     IMG_NAME: "centos-8-amd64"
   <<: *docker_build
 
-docker_ubuntu-14_04-amd64:
-  variables:
-    IMG_NAME: "ubuntu-14.04-amd64"
-  <<: *docker_build
-
 docker_ubuntu-16_04-amd64:
   variables:
     IMG_NAME: "ubuntu-16.04-amd64"
@@ -312,18 +302,10 @@ build-fedora-34-amd64:
   <<: *build-linux
   image: registry.nic.cz/labs/bird:fedora-33-amd64
 
-build-centos-7-amd64:
-  <<: *build-linux
-  image: registry.nic.cz/labs/bird:centos-7-amd64
-
 build-centos-8-amd64:
   <<: *build-linux
   image: registry.nic.cz/labs/bird:centos-8-amd64
 
-build-ubuntu-14_04-amd64:
-  <<: *build-linux
-  image: registry.nic.cz/labs/bird:ubuntu-14.04-amd64
-
 build-ubuntu-16_04-amd64:
   <<: *build-linux
   image: registry.nic.cz/labs/bird:ubuntu-16.04-amd64
@@ -466,14 +448,7 @@ pkg-fedora-33-amd64:
 pkg-fedora-34-amd64:
   <<: *pkg-rpm
   needs: [build-fedora-34-amd64]
-  image: registry.nic.cz/labs/bird:fedora-34-amd64
-
-pkg-centos-7-amd64:
-  <<: *pkg-rpm-wa
-  variables:
-    LC_ALL: en_US.UTF-8
-  needs: [build-centos-7-amd64]
-  image: registry.nic.cz/labs/bird:centos-7-amd64
+  image: registry.labs.nic.cz/labs/bird:fedora-34-amd64
 
 pkg-centos-8-amd64:
   <<: *pkg-rpm-wa
diff --git a/INSTALL b/INSTALL
index 7a179284..c1094ee5 100644
--- a/INSTALL
+++ b/INSTALL
@@ -27,9 +27,9 @@ Requirements
 
 For compiling BIRD you need these programs and libraries:
 
- - GNU C Compiler (or LLVM Clang)
+ - GNU C Compiler (or LLVM Clang) capable of compiling C11 code
  - GNU Make
- - GNU Bison
+ - GNU Bison (at least 3.0)
  - GNU M4
  - Flex
 
diff --git a/bird-gdb.py b/bird-gdb.py
index 62c0ec87..077703f9 100644
--- a/bird-gdb.py
+++ b/bird-gdb.py
@@ -122,7 +122,7 @@ class BIRDFLinePrinter(BIRDPrinter):
                         "n": n,
                         "code": str(self.val['items'][n]['fi_code']),
                     } if n % 8 == 0 else str(self.val['items'][n]['fi_code']) for n in range(cnt)]))
-        
+
 
 class BIRDFExecStackPrinter(BIRDPrinter):
     "Print BIRD's struct f_exec_stack"
@@ -140,6 +140,118 @@ class BIRDFExecStackPrinter(BIRDPrinter):
                     "n": n
                         } for n in range(cnt-1, -1, -1) ])
 
+
+class BIRD:
+    def skip_back(t, i, v):
+        if isinstance(t, str):
+            t = gdb.lookup_type(t)
+        elif isinstance(t, gdb.Value):
+            t = gdb.lookup_type(t.string())
+        elif not isinstance(t, gdb.Type):
+            raise Exception(f"First argument of skip_back(t, i, v) must be a type, got {type(t)}")
+
+        t = t.strip_typedefs()
+        nullptr = gdb.Value(0).cast(t.pointer())
+
+        if isinstance(i, gdb.Value):
+            i = i.string()
+        elif not isinstance(i, str):
+            raise Exception(f"Second argument of skip_back(t, i, v) must be a item name, got {type(i)}")
+
+        if not isinstance(v, gdb.Value):
+            raise Exception(f"Third argument of skip_back(t, i, v) must be a value, got {type(v)}")
+        if v.type.code != gdb.TYPE_CODE_PTR and v.type.code != gdb.TYPE_CODE_REF:
+            raise Exception(f"Third argument of skip_back(t, i, v) must be a pointer, is {v.type} ({v.type.code})")
+        if v.type.target().strip_typedefs() != nullptr[i].type:
+            raise Exception(f"Third argument of skip_back(t, i, v) points to type {v.type.target().strip_typedefs()}, should be {nullptr[i].type}")
+
+        uintptr_t = gdb.lookup_type("uintptr_t")
+        taddr = v.dereference().address.cast(uintptr_t) - nullptr[i].address.cast(uintptr_t)
+        return gdb.Value(taddr).cast(t.pointer())
+
+    class skip_back_gdb(gdb.Function):
+        "Given address of a structure item, returns address of the structure, as the SKIP_BACK macro does"
+        def __init__(self):
+            gdb.Function.__init__(self, "SKIP_BACK")
+
+        def invoke(self, t, i, v):
+            return BIRD.skip_back(t, i, v)
+
+
+BIRD.skip_back_gdb()
+
+
+class BIRDList:
+    def __init__(self, val):
+        ltype = val.type.strip_typedefs()
+        if ltype.code != gdb.TYPE_CODE_UNION or ltype.tag != "list":
+            raise Exception(f"Not a list, is type {ltype}")
+
+        self.head = val["head"]
+        self.tail_node = val["tail_node"]
+
+        if str(self.head.address) == '0x0':
+            raise Exception("List head is NULL")
+
+        if str(self.tail_node["prev"].address) == '0x0':
+            raise Exception("List tail is NULL")
+
+    def walk(self, do):
+        cur = self.head
+        while cur.dereference() != self.tail_node:
+            do(cur)
+            cur = cur.dereference()["next"]
+
+
+class BIRDListLength(gdb.Function):
+    """Returns length of the list, as in
+    print $list_length(routing_tables)"""
+    def __init__(self):
+        super(BIRDListLength, self).__init__("list_length")
+
+    def count(self, _):
+        self.cnt += 1
+
+    def invoke(self, l):
+        self.cnt = 0
+        BIRDList(l).walk(self.count)
+        return self.cnt
+
+BIRDListLength()
+
+class BIRDListItem(gdb.Function):
+    """Returns n-th item of the list."""
+    def __init__(self):
+        super(BIRDListItem, self).__init__("list_item")
+
+    class BLException(Exception):
+        def __init__(self, node, msg):
+            Exception.__init__(self, msg)
+            self.node = node
+
+    def count(self, node):
+        if self.cnt == self.pos:
+            raise self.BLException(node, "Node found")
+
+        self.cnt += 1
+
+    def invoke(self, l, n, t=None, item="n"):
+        self.cnt = 0
+        self.pos = n
+        bl = BIRDList(l)
+        try:
+            bl.walk(self.count)
+        except self.BLException as e:
+            if t is None:
+                return e.node
+            else:
+                return BIRD.skip_back(t, item, e.node)
+
+        raise Exception("List too short")
+
+BIRDListItem()
+
+
 def register_printers(objfile):
     objfile.pretty_printers.append(BIRDFInstPrinter.lookup)
     objfile.pretty_printers.append(BIRDFValPrinter.lookup)
diff --git a/lib/birdlib.h b/lib/birdlib.h
index 25545fc3..bdf69309 100644
--- a/lib/birdlib.h
+++ b/lib/birdlib.h
@@ -15,7 +15,7 @@
 /* Ugly structure offset handling macros */
 
 #define OFFSETOF(s, i) ((size_t) &((s *)0)->i)
-#define SKIP_BACK(s, i, p) ((s *)((char *)p - OFFSETOF(s, i)))
+#define SKIP_BACK(s, i, p) ({ s *_ptr = ((s *)((char *)p - OFFSETOF(s, i))); ASSERT_DIE(&_ptr->i == p); _ptr; })
 #define BIRD_ALIGN(s, a) (((s)+a-1)&~(a-1))
 #define CPU_STRUCT_ALIGN  (MAX_(_Alignof(void*), _Alignof(u64)))
 #define BIRD_CPU_ALIGN(s) BIRD_ALIGN((s), CPU_STRUCT_ALIGN)
diff --git a/lib/lists.c b/lib/lists.c
index 200576cf..1aa58085 100644
--- a/lib/lists.c
+++ b/lib/lists.c
@@ -35,11 +35,12 @@ check_list(list *l, node *n)
   if (!l)
   {
     ASSERT_DIE(n);
-    ASSERT_DIE(n->prev);
 
-    do { n = n->prev; } while (n->prev);
+    node *nn = n;
+    while (nn->prev)
+      nn = nn->prev;
 
-    l = SKIP_BACK(list, head_node, n);
+    l = SKIP_BACK(list, head_node, nn);
   }
 
   int seen = 0;
@@ -60,7 +61,7 @@ check_list(list *l, node *n)
   }
 
   ASSERT_DIE(cur == &(l->tail_node));
-  ASSERT_DIE(!n || (seen == 1));
+  ASSERT_DIE(!n || (seen == 1) || (n == &l->head_node) || (n == &l->tail_node));
 
   return 1;
 }
@@ -120,7 +121,7 @@ add_head(list *l, node *n)
 LIST_INLINE void
 insert_node(node *n, node *after)
 {
-  EXPENSIVE_CHECK(check_list(l, after));
+  EXPENSIVE_CHECK(check_list(NULL, after));
   ASSUME(n->prev == NULL);
   ASSUME(n->next == NULL);
 
@@ -141,7 +142,7 @@ insert_node(node *n, node *after)
 LIST_INLINE void
 rem_node(node *n)
 {
-  EXPENSIVE_CHECK(check_list(NULL, n));
+  EXPENSIVE_CHECK((n == n->prev) && (n == n->next) || check_list(NULL, n));
 
   node *z = n->prev;
   node *x = n->next;