static bool CheckPathRestriction (TRI_aql_field_access_t* fieldAccess,
TRI_aql_context_t* const context,
TRI_aql_node_t* vertexCollection,
const char* lookFor,
char* name,
const size_t n) {
size_t len;
assert(fieldAccess);
assert(lookFor);
len = strlen(lookFor);
if (len == 0) {
return false;
}
if (n > fieldAccess->_variableNameLength + len &&
memcmp((void*) lookFor, (void*) name, len) == 0) {
// we'll now patch the collection hint
TRI_aql_collection_hint_t* hint;
// field name is collection.source.abc, e.g. users.source._id
LOG_DEBUG("optimising PATHS() field access %s", fieldAccess->_fullName);
// we can now modify this fieldaccess in place to collection.abc, e.g. users._id
// copy trailing \0 byte as well
memmove(name, name + len - 1, n - fieldAccess->_variableNameLength - len + 2);
// attach the modified fieldaccess to the collection
hint = (TRI_aql_collection_hint_t*) (TRI_AQL_NODE_DATA(vertexCollection));
hint->_ranges = TRI_AddAccessAql(context, hint->_ranges, fieldAccess);
return true;
}
return false;
}
static void OptimisePaths (const TRI_aql_node_t* const fcallNode,
TRI_aql_context_t* const context,
TRI_aql_field_access_t* fieldAccess) {
TRI_aql_collection_hint_t* hint;
TRI_aql_node_t* args;
TRI_aql_node_t* vertexCollection;
TRI_aql_node_t* edgeCollection;
TRI_aql_node_t* direction;
char* directionValue;
char* name;
const char* lookFor;
size_t len;
size_t n;
args = TRI_AQL_NODE_MEMBER(fcallNode, 0);
if (args == NULL) {
return;
}
vertexCollection = TRI_AQL_NODE_MEMBER(args, 0);
edgeCollection = TRI_AQL_NODE_MEMBER(args, 1);
direction = TRI_AQL_NODE_MEMBER(args, 2);
assert(vertexCollection);
assert(edgeCollection);
assert(direction);
assert(fieldAccess);
n = strlen(fieldAccess->_fullName);
name = fieldAccess->_fullName + fieldAccess->_variableNameLength;
directionValue = TRI_AQL_NODE_STRING(direction);
// try to optimise the vertex collection access
if (TRI_EqualString(directionValue, "outbound")) {
lookFor = ".source.";
len = strlen(lookFor);
}
else if (TRI_EqualString(directionValue, "inbound")) {
lookFor = ".destination.";
len = strlen(lookFor);
}
else {
lookFor = NULL;
len = 0;
}
if (len > 0 &&
n > fieldAccess->_variableNameLength + len &&
memcmp((void*) lookFor, (void*) name, len) == 0) {
// field name is collection.source.XXX, e.g. users.source._id
LOG_DEBUG("optimising PATHS() field access %s", fieldAccess->_fullName);
// we can now modify this fieldaccess in place to collection.XXX, e.g. users._id
// copy trailing \0 byte as well
memmove(name, name + len - 1, n - fieldAccess->_variableNameLength - len + 2);
// attach the modified fieldaccess to the collection
hint = (TRI_aql_collection_hint_t*) (TRI_AQL_NODE_DATA(vertexCollection));
hint->_ranges = TRI_AddAccessAql(context, hint->_ranges, fieldAccess);
}
}
static void PatchVariables (TRI_aql_statement_walker_t* const walker) {
TRI_aql_context_t* context = ((aql_optimiser_t*) walker->_data)->_context;
TRI_vector_pointer_t* ranges;
size_t i, n;
ranges = TRI_GetCurrentRangesStatementWalkerAql(walker);
if (ranges == NULL) {
// no ranges defined, exit early
return;
}
// iterate over all ranges found
n = ranges->_length;
for (i = 0; i < n; ++i) {
TRI_aql_field_access_t* fieldAccess;
TRI_aql_variable_t* variable;
TRI_aql_node_t* definingNode;
TRI_aql_node_t* expressionNode;
char* variableName;
size_t scopeCount;
bool isReference;
fieldAccess = (TRI_aql_field_access_t*) TRI_AtVectorPointer(ranges, i);
assert(fieldAccess);
assert(fieldAccess->_fullName);
assert(fieldAccess->_variableNameLength > 0);
variableName = TRI_DuplicateString2Z(TRI_UNKNOWN_MEM_ZONE, fieldAccess->_fullName, fieldAccess->_variableNameLength);
if (variableName == NULL) {
// out of memory!
TRI_SetErrorContextAql(context, TRI_ERROR_OUT_OF_MEMORY, NULL);
return;
}
isReference = (fieldAccess->_type == TRI_AQL_ACCESS_REFERENCE);
variable = TRI_GetVariableStatementWalkerAql(walker, variableName, &scopeCount);
TRI_FreeString(TRI_UNKNOWN_MEM_ZONE, variableName);
if (variable == NULL) {
continue;
}
if (isReference && scopeCount > 0) {
// unfortunately, the referenced variable is in an outer scope, so we cannot use it
continue;
}
// note: we must not modify outer variables of subqueries
// get the node that defines the variable
definingNode = variable->_definingNode;
assert(definingNode != NULL);
expressionNode = NULL;
switch (definingNode->_type) {
case TRI_AQL_NODE_LET:
expressionNode = TRI_AQL_NODE_MEMBER(definingNode, 1);
break;
case TRI_AQL_NODE_FOR:
expressionNode = TRI_AQL_NODE_MEMBER(definingNode, 1);
break;
default: {
}
}
if (expressionNode != NULL) {
if (expressionNode->_type == TRI_AQL_NODE_FCALL) {
// the defining node is a function call
// get the function name
TRI_aql_function_t* function = TRI_AQL_NODE_DATA(expressionNode);
if (function->optimise != NULL) {
// call the function's optimise callback
function->optimise(expressionNode, context, fieldAccess);
}
}
if (expressionNode->_type == TRI_AQL_NODE_COLLECTION) {
TRI_aql_collection_hint_t* hint = (TRI_aql_collection_hint_t*) (TRI_AQL_NODE_DATA(expressionNode));
// set new value
hint->_ranges = TRI_AddAccessAql(context, hint->_ranges, fieldAccess);
}
}
}
}
