ovsdb-idl: Change interface to conditional monitoring.

Most users of OVSDB react to whatever is currently in their view of the
database, as opposed to keeping track of changes and reacting to those
changes individually.  The interface to conditional monitoring was
different, in that it expected the client to say what to add or remove from
monitoring instead of what to monitor.  This seemed reasonable at the time,
but in practice it turns out that the usual approach actually works better,
because the condition is generally a function of the data visible in the
database.  This commit changes the approach.

This commit also changes the meaning of an empty condition for a table.
Previously, an empty condition meant to replicate every row.  Now, an empty
condition means to replicate no rows.  This is more convenient for code
that gradually constructs conditions, because it does not need special
cases for replicating nothing.

This commit also changes the internal implementation of conditions from
linked lists to arrays.  I just couldn't see an advantage to using linked
lists.

Signed-off-by: Ben Pfaff <blp@ovn.org>
Acked-by: Liran Schour <lirans@il.ibm.com>

1 files changed, 12 insertions, 191 deletions

diff --git a/ovsdb/ovsdb-idlc.in b/ovsdb/ovsdb-idlc.in
index cf6cd5845..f1c7a3598 100755
--- a/ovsdb/ovsdb-idlc.in
+++ b/ovsdb/ovsdb-idlc.in
@@ -243,7 +243,7 @@ bool %(s)s_is_updated(const struct %(s)s *, enum %(s)s_column_id);
                 print 'void %(s)s_update_%(c)s_delvalue(const struct %(s)s *, ' % {'s': structName, 'c': columnName},
                 print '%(valtype)s);' % {'valtype':column.type.key.to_const_c_type(prefix)}
 
-            print 'void %(s)s_add_clause_%(c)s(struct ovsdb_idl *idl, enum ovsdb_function function,' % {'s': structName, 'c': columnName},
+            print 'void %(s)s_add_clause_%(c)s(struct ovsdb_idl_condition *, enum ovsdb_function function,' % {'s': structName, 'c': columnName},
             if column.type.is_smap():
                 args = ['const struct smap *']
             else:
@@ -252,22 +252,7 @@ bool %(s)s_is_updated(const struct %(s)s *, enum %(s)s_column_id);
                 args = ['%(type)s%(name)s' % member for member in members]
             print '%s);' % ', '.join(args)
 
-        print 'void %s_add_clause_true(struct ovsdb_idl *idl);' % structName
-        print 'void %s_add_clause_false(struct ovsdb_idl *idl);' % structName
-
-        print
-        for columnName, column in sorted_columns(table):
-            print 'void %(s)s_remove_clause_%(c)s(struct ovsdb_idl *idl, enum ovsdb_function function,' % {'s': structName, 'c': columnName},
-            if column.type.is_smap():
-                args = ['const struct smap *']
-            else:
-                comment, members = cMembers(prefix, tableName, columnName,
-                                            column, True, refTable=False)
-                args = ['%(type)s%(name)s' % member for member in members]
-            print '%s);' % ', '.join(args)
-
-        print 'void %s_remove_clause_true(struct ovsdb_idl *idl);' % structName
-        print 'void %s_remove_clause_false(struct ovsdb_idl *idl);' % structName
+            print 'void %(s)s_set_condition(struct ovsdb_idl *, struct ovsdb_idl_condition *);' % {'s': structName},
 
         print
 
@@ -870,7 +855,7 @@ void
             if type.is_smap():
                 print comment
                 print """void
-%(s)s_add_clause_%(c)s(struct ovsdb_idl *idl, enum ovsdb_function function, const struct smap *%(c)s)
+%(s)s_add_clause_%(c)s(struct ovsdb_idl_condition *cond, enum ovsdb_function function, const struct smap *%(c)s)
 {
     struct ovsdb_datum datum;
 
@@ -880,8 +865,7 @@ void
         ovsdb_datum_init_empty(&datum);
     }
 
-    ovsdb_idl_condition_add_clause(idl,
-                                   &%(p)stable_%(tl)s,
+    ovsdb_idl_condition_add_clause(cond,
                                    function,
                                    &%(s)s_col_%(c)s,
                                    &datum);
@@ -911,7 +895,7 @@ void
 
             print comment
             print 'void'
-            print '%(s)s_add_clause_%(c)s(struct ovsdb_idl *idl, enum ovsdb_function function, %(args)s)' % \
+            print '%(s)s_add_clause_%(c)s(struct ovsdb_idl_condition *cond, enum ovsdb_function function, %(args)s)' % \
                 {'s': structName, 'c': columnName,
                  'args': ', '.join(['%(type)s%(name)s' % m for m in members])}
             print "{"
@@ -975,7 +959,7 @@ void
                 print "    ovsdb_datum_sort_unique(&datum, %s, %s);" % (
                     type.key.toAtomicType(), valueType)
 
-            print"""    ovsdb_idl_condition_add_clause(idl, &%(p)stable_%(tl)s,
+            print"""    ovsdb_idl_condition_add_clause(cond,
                           function,
                           &%(s)s_col_%(c)s,
                           &datum);\
@@ -990,177 +974,14 @@ void
                 print "    free(%s);" % var
             print "}"
 
-        print """\
-void
-%(s)s_add_clause_false(struct ovsdb_idl *idl)
-{
-    struct ovsdb_datum datum;
-
-    ovsdb_datum_init_empty(&datum);
-    ovsdb_idl_condition_add_clause(idl, &%(p)stable_%(tl)s, OVSDB_F_FALSE, NULL, &datum);
-}""" % {'s': structName,
-        'tl': tableName.lower(),
-        'p': prefix,
-        'P': prefix.upper()}
-
-        print """void
-%(s)s_add_clause_true(struct ovsdb_idl *idl)
-{
-    struct ovsdb_datum datum;
-
-    ovsdb_datum_init_empty(&datum);
-    ovsdb_idl_condition_add_clause(idl, &%(p)stable_%(tl)s, OVSDB_F_TRUE, NULL, &datum);
-}""" % {'s': structName,
-        'tl': tableName.lower(),
-        'p': prefix,
-        'P': prefix.upper()}
-
-        # Remove clause functions.
-        for columnName, column in sorted_columns(table):
-            type = column.type
-
-            comment, members = cMembers(prefix, tableName, columnName,
-                                        column, True, refTable=False)
-
-            if type.is_smap():
-                print comment
-                print """void
-%(s)s_remove_clause_%(c)s(struct ovsdb_idl *idl, enum ovsdb_function function, const struct smap *%(c)s)
-{
-    struct ovsdb_datum datum;
-
-    if (%(c)s) {
-        ovsdb_datum_from_smap(&datum, %(c)s);
-    } else {
-        ovsdb_datum_init_empty(&datum);
-    }
-
-    ovsdb_idl_condition_remove_clause(idl, &%(p)stable_%(tl)s,
-                                      function,
-                                      &%(s)s_col_%(c)s,
-                                      &datum);
-
-    ovsdb_datum_destroy(&datum, &%(s)s_col_%(c)s.type);
-}
-""" % {'tl': tableName.lower(),
-       'p': prefix,
-       'P': prefix.upper(),
-       's': structName,
-       'S': structName.upper(),
-       'c': columnName}
-                continue
-
-            keyVar = members[0]['name']
-            nVar = None
-            valueVar = None
-            if type.value:
-                valueVar = members[1]['name']
-                if len(members) > 2:
-                    nVar = members[2]['name']
-            else:
-                if len(members) > 1:
-                    nVar = members[1]['name']
-
-            print comment
-            print 'void'
-            print '%(s)s_remove_clause_%(c)s(struct ovsdb_idl *idl, enum ovsdb_function function, %(args)s)' % \
-                {'s': structName, 'c': columnName,
-                 'args': ', '.join(['%(type)s%(name)s' % m for m in members])}
-            print "{"
-            print "    struct ovsdb_datum datum;"
-            free = []
-            if type.n_min == 1 and type.n_max == 1:
-                print "    union ovsdb_atom key;"
-                if type.value:
-                    print "    union ovsdb_atom value;"
-                print
-                print "    datum.n = 1;"
-                print "    datum.keys = &key;"
-                print "    " + type.key.assign_c_value_casting_away_const("key.%s" % type.key.type.to_string(), keyVar, refTable=False)
-                if type.value:
-                    print "    datum.values = &value;"
-                    print "    "+ type.value.assign_c_value_casting_away_const("value.%s" % type.value.type.to_string(), valueVar, refTable=False)
-                else:
-                    print "    datum.values = NULL;"
-            elif type.is_optional_pointer():
-                print "    union ovsdb_atom key;"
-                print
-                print "    if (%s) {" % keyVar
-                print "        datum.n = 1;"
-                print "        datum.keys = &key;"
-                print "        " + type.key.assign_c_value_casting_away_const("key.%s" % type.key.type.to_string(), keyVar, refTable=False)
-                print "    } else {"
-                print "        datum.n = 0;"
-                print "        datum.keys = NULL;"
-                print "    }"
-                print "    datum.values = NULL;"
-            elif type.n_max == 1:
-                print "    union ovsdb_atom key;"
-                print
-                print "    if (%s) {" % nVar
-                print "        datum.n = 1;"
-                print "        datum.keys = &key;"
-                print "        " + type.key.assign_c_value_casting_away_const("key.%s" % type.key.type.to_string(), "*" + keyVar, refTable=False)
-                print "    } else {"
-                print "        datum.n = 0;"
-                print "        datum.keys = NULL;"
-                print "    }"
-                print "    datum.values = NULL;"
-            else:
-                print "    datum.n = %s;" % nVar
-                print "    datum.keys = %s ? xmalloc(%s * sizeof *datum.keys) : NULL;" % (nVar, nVar)
-                free += ['datum.keys']
-                if type.value:
-                    free += ['datum.values']
-                    print "    datum.values = xmalloc(%s * sizeof *datum.values);" % nVar
-                else:
-                    print "    datum.values = NULL;"
-                print "    for (size_t i = 0; i < %s; i++) {" % nVar
-                print "        " + type.key.assign_c_value_casting_away_const("datum.keys[i].%s" % type.key.type.to_string(), "%s[i]" % keyVar, refTable=False)
-                if type.value:
-                    print "        " + type.value.assign_c_value_casting_away_const("datum.values[i].%s" % type.value.type.to_string(), "%s[i]" % valueVar, refTable=False)
-                print "    }"
-                if type.value:
-                    valueType = type.value.toAtomicType()
-                else:
-                    valueType = "OVSDB_TYPE_VOID"
-                print "    ovsdb_datum_sort_unique(&datum, %s, %s);" % (
-                    type.key.toAtomicType(), valueType)
-
-            print"""    ovsdb_idl_condition_remove_clause(idl, &%(p)stable_%(tl)s,
-                          function,
-                          &%(s)s_col_%(c)s,
-                          &datum);\
-""" % {'tl': tableName.lower(),
-       'p': prefix,
-       'P': prefix.upper(),
-       's': structName,
-       'S': structName.upper(),
-       'c': columnName}
-            for var in free:
-                print "    free(%s);" % var
-            print "}"
-
-        print """void
-%(s)s_remove_clause_false(struct ovsdb_idl *idl)
-{
-    struct ovsdb_datum datum;
-
-    ovsdb_datum_init_empty(&datum);
-    ovsdb_idl_condition_remove_clause(idl, &%(p)stable_%(tl)s, OVSDB_F_FALSE, NULL, &datum);
-}
-
+        print """
 void
-%(s)s_remove_clause_true(struct ovsdb_idl *idl)
+%(s)s_set_condition(struct ovsdb_idl *idl, struct ovsdb_idl_condition *condition)
 {
-    struct ovsdb_datum datum;
-
-    ovsdb_datum_init_empty(&datum);
-    ovsdb_idl_condition_remove_clause(idl, &%(p)stable_%(tl)s, OVSDB_F_TRUE, NULL, &datum);
-}""" % {'s': structName,
-        'tl': tableName.lower(),
-        'p': prefix,
-        'P': prefix.upper(),}
+    ovsdb_idl_set_condition(idl, &%(p)stable_%(tl)s, condition);
+}""" % {'p': prefix,
+        's': structName,
+        'tl': tableName.lower()}
 
         # Table columns.
         for columnName, column in sorted_columns(table):