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-rw-r--r--src/traversal/xpath.cc1670
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diff --git a/src/traversal/xpath.cc b/src/traversal/xpath.cc
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--- /dev/null
+++ b/src/traversal/xpath.cc
@@ -0,0 +1,1670 @@
+/*
+ * Copyright (c) 2003-2007, John Wiegley. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ * - Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *
+ * - Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * - Neither the name of New Artisans LLC nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "xpath.h"
+#include "parser.h"
+
+namespace ledger {
+namespace xml {
+
+#ifndef THREADSAFE
+xpath_t::token_t * xpath_t::lookahead = NULL;
+#endif
+
+void xpath_t::initialize()
+{
+ lookahead = new xpath_t::token_t;
+}
+
+void xpath_t::shutdown()
+{
+ checked_delete(lookahead);
+ lookahead = NULL;
+}
+
+void xpath_t::token_t::parse_ident(std::istream& in)
+{
+ if (in.eof()) {
+ kind = TOK_EOF;
+ return;
+ }
+ assert(in.good());
+
+ char c = peek_next_nonws(in);
+
+ if (in.eof()) {
+ kind = TOK_EOF;
+ return;
+ }
+ assert(in.good());
+
+ kind = IDENT;
+ length = 0;
+
+ char buf[256];
+ READ_INTO_(in, buf, 255, c, length,
+ std::isalnum(c) || c == '_' || c == '.' || c == '-');
+
+ switch (buf[0]) {
+ case 'a':
+ if (std::strcmp(buf, "and") == 0)
+ kind = KW_AND;
+ break;
+ case 'd':
+ if (std::strcmp(buf, "div") == 0)
+ kind = KW_DIV;
+ break;
+ case 'e':
+ if (std::strcmp(buf, "eq") == 0)
+ kind = EQUAL;
+ break;
+ case 'f':
+ if (std::strcmp(buf, "false") == 0) {
+ kind = VALUE;
+ value = false;
+ }
+ break;
+ case 'g':
+ if (std::strcmp(buf, "gt") == 0)
+ kind = GREATER;
+ else if (std::strcmp(buf, "ge") == 0)
+ kind = GREATEREQ;
+ break;
+ case 'i':
+ if (std::strcmp(buf, "is") == 0)
+ kind = EQUAL;
+ break;
+ case 'l':
+ if (std::strcmp(buf, "lt") == 0)
+ kind = LESS;
+ else if (std::strcmp(buf, "le") == 0)
+ kind = LESSEQ;
+ break;
+ case 'm':
+ if (std::strcmp(buf, "mod") == 0)
+ kind = KW_MOD;
+ break;
+ case 'n':
+ if (std::strcmp(buf, "ne") == 0)
+ kind = NEQUAL;
+ break;
+ case 'o':
+ if (std::strcmp(buf, "or") == 0)
+ kind = KW_OR;
+ break;
+ case 't':
+ if (std::strcmp(buf, "true") == 0) {
+ kind = VALUE;
+ value = true;
+ }
+ break;
+ case 'u':
+ if (std::strcmp(buf, "union") == 0)
+ kind = KW_UNION;
+ break;
+ }
+
+ if (kind == IDENT)
+ value.set_string(buf);
+}
+
+void xpath_t::token_t::next(std::istream& in, flags_t flags)
+{
+ if (in.eof()) {
+ kind = TOK_EOF;
+ return;
+ }
+ assert(in.good());
+
+ char c = peek_next_nonws(in);
+
+ if (in.eof()) {
+ kind = TOK_EOF;
+ return;
+ }
+ assert(in.good());
+
+ symbol[0] = c;
+ symbol[1] = '\0';
+
+ length = 1;
+
+ if (! (flags & XPATH_PARSE_RELAXED) &&
+ (std::isalpha(c) || c == '_')) {
+ parse_ident(in);
+ return;
+ }
+
+ switch (c) {
+ case '@':
+ in.get(c);
+ kind = AT_SYM;
+ break;
+ case '$':
+ in.get(c);
+ kind = DOLLAR;
+ break;
+
+ case '(':
+ in.get(c);
+ kind = LPAREN;
+ break;
+ case ')':
+ in.get(c);
+ kind = RPAREN;
+ break;
+
+ case '[': {
+ in.get(c);
+ if (flags & XPATH_PARSE_ALLOW_DATE) {
+ char buf[256];
+ READ_INTO_(in, buf, 255, c, length, c != ']');
+ if (c != ']')
+ unexpected(c, ']');
+ in.get(c);
+ length++;
+ interval_t timespan(buf);
+ kind = VALUE;
+ value = timespan.next();
+ } else {
+ kind = LBRACKET;
+ }
+ break;
+ }
+
+ case ']': {
+ in.get(c);
+ kind = RBRACKET;
+ break;
+ }
+
+ case '\'':
+ case '"': {
+ char delim;
+ in.get(delim);
+ char buf[4096];
+ READ_INTO_(in, buf, 4095, c, length, c != delim);
+ if (c != delim)
+ unexpected(c, delim);
+ in.get(c);
+ length++;
+ kind = VALUE;
+ value.set_string(buf);
+ break;
+ }
+
+ case '{': {
+ in.get(c);
+ amount_t temp;
+ temp.parse(in, AMOUNT_PARSE_NO_MIGRATE);
+ in.get(c);
+ if (c != '}')
+ unexpected(c, '}');
+ length++;
+ kind = VALUE;
+ value = temp;
+ break;
+ }
+
+ case '!':
+ in.get(c);
+ c = in.peek();
+ if (c == '=') {
+ in.get(c);
+ symbol[1] = c;
+ symbol[2] = '\0';
+ kind = NEQUAL;
+ length = 2;
+ break;
+ }
+ kind = EXCLAM;
+ break;
+
+ case '-':
+ in.get(c);
+ kind = MINUS;
+ break;
+ case '+':
+ in.get(c);
+ kind = PLUS;
+ break;
+
+ case '*':
+ in.get(c);
+ kind = STAR;
+ break;
+
+ case '/':
+ in.get(c);
+ kind = SLASH;
+ break;
+
+ case '=':
+ in.get(c);
+ kind = EQUAL;
+ break;
+
+ case '<':
+ in.get(c);
+ if (in.peek() == '=') {
+ in.get(c);
+ symbol[1] = c;
+ symbol[2] = '\0';
+ kind = LESSEQ;
+ length = 2;
+ break;
+ }
+ kind = LESS;
+ break;
+
+ case '>':
+ in.get(c);
+ if (in.peek() == '=') {
+ in.get(c);
+ symbol[1] = c;
+ symbol[2] = '\0';
+ kind = GREATEREQ;
+ length = 2;
+ break;
+ }
+ kind = GREATER;
+ break;
+
+ case '|':
+ in.get(c);
+ kind = PIPE;
+ break;
+ case ',':
+ in.get(c);
+ kind = COMMA;
+ break;
+
+ case '.':
+ in.get(c);
+ c = in.peek();
+ if (c == '.') {
+ in.get(c);
+ length++;
+ kind = DOTDOT;
+ break;
+ }
+ else if (! std::isdigit(c)) {
+ kind = DOT;
+ break;
+ }
+ in.unget(); // put the first '.' back
+ // fall through...
+
+ default:
+ if (! (flags & XPATH_PARSE_RELAXED)) {
+ kind = UNKNOWN;
+ } else {
+ amount_t temp;
+ unsigned long pos = 0;
+
+ // When in relaxed parsing mode, we want to migrate commodity
+ // flags so that any precision specified by the user updates the
+ // current maximum displayed precision.
+ try {
+ pos = (long)in.tellg();
+
+ unsigned char parse_flags = 0;
+ if (flags & XPATH_PARSE_NO_MIGRATE)
+ parse_flags |= AMOUNT_PARSE_NO_MIGRATE;
+ if (flags & XPATH_PARSE_NO_REDUCE)
+ parse_flags |= AMOUNT_PARSE_NO_REDUCE;
+
+ temp.parse(in, parse_flags);
+
+ kind = VALUE;
+ value = temp;
+ }
+ catch (amount_error& err) {
+ // If the amount had no commodity, it must be an unambiguous
+ // variable reference
+
+ // jww (2007-04-19): There must be a more efficient way to do this!
+ if (std::strcmp(err.what(), "No quantity specified for amount") == 0) {
+ in.clear();
+ in.seekg(pos, std::ios::beg);
+
+ c = in.peek();
+ assert(! (std::isdigit(c) || c == '.'));
+ parse_ident(in);
+ } else {
+ throw;
+ }
+ }
+ }
+ break;
+ }
+}
+
+void xpath_t::token_t::rewind(std::istream& in)
+{
+ for (unsigned int i = 0; i < length; i++)
+ in.unget();
+}
+
+
+void xpath_t::token_t::unexpected()
+{
+ switch (kind) {
+ case TOK_EOF:
+ throw_(parse_error, "Unexpected end of expression");
+ case IDENT:
+ throw_(parse_error, "Unexpected symbol '" << value << "'");
+ case VALUE:
+ throw_(parse_error, "Unexpected value '" << value << "'");
+ default:
+ throw_(parse_error, "Unexpected operator '" << symbol << "'");
+ }
+}
+
+void xpath_t::token_t::unexpected(char c, char wanted)
+{
+ if ((unsigned char) c == 0xff) {
+ if (wanted)
+ throw_(parse_error, "Missing '" << wanted << "'");
+ else
+ throw_(parse_error, "Unexpected end");
+ } else {
+ if (wanted)
+ throw_(parse_error, "Invalid char '" << c <<
+ "' (wanted '" << wanted << "')");
+ else
+ throw_(parse_error, "Invalid char '" << c << "'");
+ }
+}
+
+
+void xpath_t::scope_t::define(const string& name, const value_t& val) {
+ define(name, op_t::wrap_value(val));
+}
+
+void xpath_t::symbol_scope_t::define(const string& name, ptr_op_t def)
+{
+ DEBUG("ledger.xpath.syms", "Defining '" << name << "' = " << def);
+
+ std::pair<symbol_map::iterator, bool> result
+ = symbols.insert(symbol_map::value_type(name, def));
+ if (! result.second) {
+ symbol_map::iterator i = symbols.find(name);
+ assert(i != symbols.end());
+ symbols.erase(i);
+
+ std::pair<symbol_map::iterator, bool> result2
+ = symbols.insert(symbol_map::value_type(name, def));
+ if (! result2.second)
+ throw_(compile_error,
+ "Redefinition of '" << name << "' in same scope");
+ }
+}
+
+namespace {
+ value_t xpath_fn_last(xpath_t::call_scope_t& scope)
+ {
+ xpath_t::context_scope_t& context(CONTEXT_SCOPE(scope));
+ return context.size();
+ }
+
+ value_t xpath_fn_position(xpath_t::call_scope_t& scope)
+ {
+ xpath_t::context_scope_t& context(CONTEXT_SCOPE(scope));
+ return context.index() + 1;
+ }
+
+ value_t xpath_fn_text(xpath_t::call_scope_t& scope)
+ {
+ xpath_t::context_scope_t& context(CONTEXT_SCOPE(scope));
+ return value_t(context.xml_node().to_value().to_string(), true);
+ }
+
+ value_t xpath_fn_type(xpath_t::call_scope_t& scope)
+ {
+ if (scope.size() == 0) {
+ xpath_t::context_scope_t& context(CONTEXT_SCOPE(scope));
+ return string_value(context.value().label());
+ }
+ else if (scope.size() == 1) {
+ return string_value(scope[0].label());
+ }
+ else {
+ assert(false);
+ return string_value("INVALID");
+ }
+ }
+}
+
+xpath_t::ptr_op_t
+xpath_t::symbol_scope_t::lookup(const string& name)
+{
+ switch (name[0]) {
+ case 'l':
+ if (name == "last")
+ return WRAP_FUNCTOR(bind(xpath_fn_last, _1));
+ break;
+
+ case 'p':
+ if (name == "position")
+ return WRAP_FUNCTOR(bind(xpath_fn_position, _1));
+ break;
+
+ case 't':
+ if (name == "text")
+ return WRAP_FUNCTOR(bind(xpath_fn_text, _1));
+ else if (name == "type")
+ return WRAP_FUNCTOR(bind(xpath_fn_type, _1));
+ break;
+ }
+
+ symbol_map::const_iterator i = symbols.find(name);
+ if (i != symbols.end())
+ return (*i).second;
+
+ return child_scope_t::lookup(name);
+}
+
+
+xpath_t::ptr_op_t
+xpath_t::parse_value_term(std::istream& in, flags_t tflags) const
+{
+ ptr_op_t node;
+
+ token_t& tok = next_token(in, tflags);
+
+ switch (tok.kind) {
+ case token_t::VALUE:
+ node = new op_t(op_t::VALUE);
+ node->set_value(tok.value);
+ break;
+
+ case token_t::IDENT: {
+#if 0
+#ifdef USE_BOOST_PYTHON
+ if (tok.value->as_string() == "lambda") // special
+ try {
+ char c, buf[4096];
+
+ std::strcpy(buf, "lambda ");
+ READ_INTO(in, &buf[7], 4000, c, true);
+
+ ptr_op_t eval = new op_t(op_t::O_EVAL);
+ ptr_op_t lambda = new op_t(op_t::FUNCTION);
+ lambda->functor = new python_functor_t(python_eval(buf));
+ eval->set_left(lambda);
+ ptr_op_t sym = new op_t(op_t::SYMBOL);
+ sym->name = new string("__ptr");
+ eval->set_right(sym);
+
+ node = eval;
+
+ goto done;
+ }
+ catch(const boost::python::error_already_set&) {
+ throw_(parse_error, "Error parsing lambda expression");
+ }
+#endif /* USE_BOOST_PYTHON */
+#endif
+
+ string ident = tok.value.as_string();
+
+ // An identifier followed by ( represents a function call
+ tok = next_token(in, tflags);
+ if (tok.kind == token_t::LPAREN) {
+ node = new op_t(op_t::FUNC_NAME);
+ node->set_string(ident);
+
+ ptr_op_t call_node(new op_t(op_t::O_CALL));
+ call_node->set_left(node);
+ call_node->set_right(parse_value_expr(in, tflags | XPATH_PARSE_PARTIAL));
+
+ tok = next_token(in, tflags);
+ if (tok.kind != token_t::RPAREN)
+ tok.unexpected(0xff, ')');
+
+ node = call_node;
+ } else {
+ if (std::isdigit(ident[0])) {
+ node = new op_t(op_t::ARG_INDEX);
+ node->set_long(lexical_cast<unsigned int>(ident.c_str()));
+ }
+ else if (optional<node_t::nameid_t> id =
+ document_t::lookup_builtin_id(ident)) {
+ node = new op_t(op_t::NODE_ID);
+ node->set_name(*id);
+ }
+ else {
+ node = new op_t(op_t::NODE_NAME);
+ node->set_string(ident);
+ }
+ push_token(tok);
+ }
+ break;
+ }
+
+ case token_t::AT_SYM: {
+ tok = next_token(in, tflags);
+ if (tok.kind != token_t::IDENT)
+ throw_(parse_error, "@ symbol must be followed by attribute name");
+
+ string ident = tok.value.as_string();
+ if (optional<node_t::nameid_t> id = document_t::lookup_builtin_id(ident)) {
+ node = new op_t(op_t::ATTR_ID);
+ node->set_name(*id);
+ }
+ else {
+ node = new op_t(op_t::ATTR_NAME);
+ node->set_string(ident);
+ }
+ break;
+ }
+
+ case token_t::DOLLAR:
+ tok = next_token(in, tflags);
+ if (tok.kind != token_t::IDENT)
+ throw parse_error("$ symbol must be followed by variable name");
+
+ node = new op_t(op_t::VAR_NAME);
+ node->set_string(tok.value.as_string());
+ break;
+
+ case token_t::DOT:
+ node = new op_t(op_t::NODE_ID);
+ node->set_name(document_t::CURRENT);
+ break;
+ case token_t::DOTDOT:
+ node = new op_t(op_t::NODE_ID);
+ node->set_name(document_t::PARENT);
+ break;
+ case token_t::SLASH:
+ node = new op_t(op_t::NODE_ID);
+ node->set_name(document_t::ROOT);
+ push_token();
+ break;
+ case token_t::STAR:
+ node = new op_t(op_t::NODE_ID);
+ node->set_name(document_t::ALL);
+ break;
+
+ case token_t::LPAREN:
+ node = new op_t(op_t::O_COMMA);
+ node->set_left(parse_value_expr(in, tflags | XPATH_PARSE_PARTIAL));
+ if (! node->left())
+ throw_(parse_error, tok.symbol << " operator not followed by argument");
+
+ tok = next_token(in, tflags);
+ if (tok.kind != token_t::RPAREN)
+ tok.unexpected(0xff, ')');
+ break;
+
+ default:
+ push_token(tok);
+ break;
+ }
+
+#if 0
+#ifdef USE_BOOST_PYTHON
+ done:
+#endif
+#endif
+ return node;
+}
+
+xpath_t::ptr_op_t
+xpath_t::parse_predicate_expr(std::istream& in, flags_t tflags) const
+{
+ ptr_op_t node(parse_value_term(in, tflags));
+
+ if (node) {
+ token_t& tok = next_token(in, tflags);
+ while (tok.kind == token_t::LBRACKET) {
+ ptr_op_t prev(node);
+ node = new op_t(op_t::O_PRED);
+ node->set_left(prev);
+ node->set_right(parse_value_expr(in, tflags | XPATH_PARSE_PARTIAL));
+ if (! node->right())
+ throw_(parse_error, "[ operator not followed by valid expression");
+
+ tok = next_token(in, tflags);
+ if (tok.kind != token_t::RBRACKET)
+ tok.unexpected(0xff, ']');
+
+ tok = next_token(in, tflags);
+ }
+
+ push_token(tok);
+ }
+
+ return node;
+}
+
+xpath_t::ptr_op_t
+xpath_t::parse_path_expr(std::istream& in, flags_t tflags) const
+{
+ ptr_op_t node(parse_predicate_expr(in, tflags));
+
+ if (node) {
+ token_t& tok = next_token(in, tflags);
+ if (tok.kind == token_t::SLASH) {
+ ptr_op_t prev(node);
+
+ tok = next_token(in, tflags);
+ node = new op_t(tok.kind == token_t::SLASH ?
+ op_t::O_RFIND : op_t::O_FIND);
+ if (tok.kind != token_t::SLASH)
+ push_token(tok);
+
+ node->set_left(prev);
+ node->set_right(parse_path_expr(in, tflags));
+ if (! node->right())
+ throw_(parse_error, "/ operator not followed by a valid term");
+ } else {
+ push_token(tok);
+ }
+ }
+
+ return node;
+}
+
+xpath_t::ptr_op_t
+xpath_t::parse_unary_expr(std::istream& in, flags_t tflags) const
+{
+ ptr_op_t node;
+
+ token_t& tok = next_token(in, tflags);
+
+ switch (tok.kind) {
+ case token_t::EXCLAM: {
+ ptr_op_t texpr(parse_path_expr(in, tflags));
+ if (! texpr)
+ throw_(parse_error,
+ tok.symbol << " operator not followed by argument");
+
+ // A very quick optimization
+ if (texpr->kind == op_t::VALUE) {
+ texpr->as_value().in_place_negate();
+ node = texpr;
+ } else {
+ node = new op_t(op_t::O_NOT);
+ node->set_left(texpr);
+ }
+ break;
+ }
+
+ case token_t::MINUS: {
+ ptr_op_t texpr(parse_path_expr(in, tflags));
+ if (! texpr)
+ throw_(parse_error,
+ tok.symbol << " operator not followed by argument");
+
+ // A very quick optimization
+ if (texpr->kind == op_t::VALUE) {
+ texpr->as_value().in_place_negate();
+ node = texpr;
+ } else {
+ node = new op_t(op_t::O_NEG);
+ node->set_left(texpr);
+ }
+ break;
+ }
+
+ default:
+ push_token(tok);
+ node = parse_path_expr(in, tflags);
+ break;
+ }
+
+ return node;
+}
+
+xpath_t::ptr_op_t
+xpath_t::parse_union_expr(std::istream& in, flags_t tflags) const
+{
+ ptr_op_t node(parse_unary_expr(in, tflags));
+
+ if (node) {
+ token_t& tok = next_token(in, tflags);
+ if (tok.kind == token_t::PIPE || tok.kind == token_t::KW_UNION) {
+ ptr_op_t prev(node);
+ node = new op_t(op_t::O_UNION);
+ node->set_left(prev);
+ node->set_right(parse_union_expr(in, tflags));
+ if (! node->right())
+ throw_(parse_error,
+ tok.symbol << " operator not followed by argument");
+ } else {
+ push_token(tok);
+ }
+ }
+
+ return node;
+}
+
+xpath_t::ptr_op_t
+xpath_t::parse_mul_expr(std::istream& in, flags_t tflags) const
+{
+ ptr_op_t node(parse_union_expr(in, tflags));
+
+ if (node) {
+ token_t& tok = next_token(in, tflags);
+ if (tok.kind == token_t::STAR || tok.kind == token_t::KW_DIV) {
+ ptr_op_t prev(node);
+ node = new op_t(tok.kind == token_t::STAR ?
+ op_t::O_MUL : op_t::O_DIV);
+ node->set_left(prev);
+ node->set_right(parse_mul_expr(in, tflags));
+ if (! node->right())
+ throw_(parse_error,
+ tok.symbol << " operator not followed by argument");
+
+ tok = next_token(in, tflags);
+ }
+ push_token(tok);
+ }
+
+ return node;
+}
+
+xpath_t::ptr_op_t
+xpath_t::parse_add_expr(std::istream& in, flags_t tflags) const
+{
+ ptr_op_t node(parse_mul_expr(in, tflags));
+
+ if (node) {
+ token_t& tok = next_token(in, tflags);
+ if (tok.kind == token_t::PLUS ||
+ tok.kind == token_t::MINUS) {
+ ptr_op_t prev(node);
+ node = new op_t(tok.kind == token_t::PLUS ?
+ op_t::O_ADD : op_t::O_SUB);
+ node->set_left(prev);
+ node->set_right(parse_add_expr(in, tflags));
+ if (! node->right())
+ throw_(parse_error,
+ tok.symbol << " operator not followed by argument");
+
+ tok = next_token(in, tflags);
+ }
+ push_token(tok);
+ }
+
+ return node;
+}
+
+xpath_t::ptr_op_t
+xpath_t::parse_logic_expr(std::istream& in, flags_t tflags) const
+{
+ ptr_op_t node(parse_add_expr(in, tflags));
+
+ if (node) {
+ op_t::kind_t kind = op_t::LAST;
+ flags_t _flags = tflags;
+ token_t& tok = next_token(in, tflags);
+ switch (tok.kind) {
+ case token_t::EQUAL:
+ kind = op_t::O_EQ;
+ break;
+ case token_t::NEQUAL:
+ kind = op_t::O_NEQ;
+ break;
+ case token_t::LESS:
+ kind = op_t::O_LT;
+ break;
+ case token_t::LESSEQ:
+ kind = op_t::O_LTE;
+ break;
+ case token_t::GREATER:
+ kind = op_t::O_GT;
+ break;
+ case token_t::GREATEREQ:
+ kind = op_t::O_GTE;
+ break;
+ default:
+ push_token(tok);
+ break;
+ }
+
+ if (kind != op_t::LAST) {
+ ptr_op_t prev(node);
+ node = new op_t(kind);
+ node->set_left(prev);
+ node->set_right(parse_add_expr(in, _flags));
+
+ if (! node->right()) {
+ if (tok.kind == token_t::PLUS)
+ throw_(parse_error,
+ tok.symbol << " operator not followed by argument");
+ else
+ throw_(parse_error,
+ tok.symbol << " operator not followed by argument");
+ }
+ }
+ }
+
+ return node;
+}
+
+xpath_t::ptr_op_t
+xpath_t::parse_and_expr(std::istream& in, flags_t tflags) const
+{
+ ptr_op_t node(parse_logic_expr(in, tflags));
+
+ if (node) {
+ token_t& tok = next_token(in, tflags);
+ if (tok.kind == token_t::KW_AND) {
+ ptr_op_t prev(node);
+ node = new op_t(op_t::O_AND);
+ node->set_left(prev);
+ node->set_right(parse_and_expr(in, tflags));
+ if (! node->right())
+ throw_(parse_error,
+ tok.symbol << " operator not followed by argument");
+ } else {
+ push_token(tok);
+ }
+ }
+ return node;
+}
+
+xpath_t::ptr_op_t
+xpath_t::parse_or_expr(std::istream& in, flags_t tflags) const
+{
+ ptr_op_t node(parse_and_expr(in, tflags));
+
+ if (node) {
+ token_t& tok = next_token(in, tflags);
+ if (tok.kind == token_t::KW_OR) {
+ ptr_op_t prev(node);
+ node = new op_t(op_t::O_OR);
+ node->set_left(prev);
+ node->set_right(parse_or_expr(in, tflags));
+ if (! node->right())
+ throw_(parse_error,
+ tok.symbol << " operator not followed by argument");
+ } else {
+ push_token(tok);
+ }
+ }
+ return node;
+}
+
+xpath_t::ptr_op_t
+xpath_t::parse_value_expr(std::istream& in, flags_t tflags) const
+{
+ ptr_op_t node(parse_or_expr(in, tflags));
+
+ if (node) {
+ token_t& tok = next_token(in, tflags);
+ if (tok.kind == token_t::COMMA) {
+ ptr_op_t prev(node);
+ node = new op_t(op_t::O_COMMA);
+ node->set_left(prev);
+ node->set_right(parse_value_expr(in, tflags));
+ if (! node->right())
+ throw_(parse_error,
+ tok.symbol << " operator not followed by argument");
+ tok = next_token(in, tflags);
+ }
+
+ if (tok.kind != token_t::TOK_EOF) {
+ if (tflags & XPATH_PARSE_PARTIAL)
+ push_token(tok);
+ else
+ tok.unexpected();
+ }
+ }
+ else if (! (tflags & XPATH_PARSE_PARTIAL)) {
+ throw_(parse_error, "Failed to parse value expression");
+ }
+
+ return node;
+}
+
+xpath_t::ptr_op_t
+xpath_t::parse_expr(std::istream& in, flags_t tflags) const
+{
+ ptr_op_t node(parse_value_expr(in, tflags));
+
+ if (use_lookahead) {
+ use_lookahead = false;
+#ifdef THREADSAFE
+ lookahead.rewind(in);
+#else
+ lookahead->rewind(in);
+#endif
+ }
+#ifdef THREADSAFE
+ lookahead.clear();
+#else
+ lookahead->clear();
+#endif
+
+ return node;
+}
+
+
+xpath_t::ptr_op_t xpath_t::op_t::compile(scope_t& scope)
+{
+ switch (kind) {
+ case VAR_NAME:
+ case FUNC_NAME:
+ if (ptr_op_t def = scope.lookup(as_string())) {
+#if 1
+ return def;
+#else
+ // Aren't definitions compiled when they go in? Would
+ // recompiling here really add any benefit?
+ return def->compile(scope);
+#endif
+ }
+ return this;
+
+ default:
+ break;
+ }
+
+ if (kind < TERMINALS)
+ return this;
+
+ ptr_op_t lhs(left()->compile(scope));
+ ptr_op_t rhs(right() ? right()->compile(scope) : ptr_op_t());
+
+ if (lhs == left() && (! rhs || rhs == right()))
+ return this;
+
+ ptr_op_t intermediate(copy(lhs, rhs));
+
+ if (lhs->is_value() && (! rhs || rhs->is_value()))
+ return wrap_value(intermediate->calc(scope));
+
+ return intermediate;
+}
+
+
+value_t xpath_t::op_t::current_value(scope_t& scope)
+{
+ xpath_t::context_scope_t& context(CONTEXT_SCOPE(scope));
+ return context.value();
+}
+
+node_t& xpath_t::op_t::current_xml_node(scope_t& scope)
+{
+ xpath_t::context_scope_t& context(CONTEXT_SCOPE(scope));
+ return context.xml_node();
+}
+
+namespace {
+ value_t select_nodes(xpath_t::scope_t& scope, const value_t& nodes,
+ xpath_t::ptr_op_t selection_path, bool recurse);
+
+ value_t select_recursively(xpath_t::scope_t& scope, node_t& xml_node,
+ xpath_t::ptr_op_t selection_path)
+ {
+ value_t result;
+
+ if (xml_node.is_parent_node()) {
+ parent_node_t& parent_node(xml_node.as_parent_node());
+ foreach (node_t * child, parent_node)
+ result.push_back(select_nodes(scope, child, selection_path, true));
+ }
+ return result;
+ }
+
+ value_t select_nodes(xpath_t::scope_t& scope, const value_t& nodes,
+ xpath_t::ptr_op_t selection_path, bool recurse)
+ {
+ if (nodes.is_null())
+ return NULL_VALUE;
+
+ value_t result;
+
+ if (! nodes.is_sequence()) {
+ xpath_t::context_scope_t node_scope(scope, nodes, 0, 1);
+ result.push_back(selection_path->calc(node_scope));
+
+ if (recurse && nodes.is_xml_node())
+ result.push_back(select_recursively(scope, *nodes.as_xml_node(),
+ selection_path));
+ } else {
+ std::size_t index = 0;
+ std::size_t size = nodes.as_sequence().size();
+
+ foreach (const value_t& node, nodes.as_sequence()) {
+ xpath_t::context_scope_t node_scope(scope, node, index, size);
+ result.push_back(selection_path->calc(node_scope));
+
+ if (recurse && nodes.is_xml_node())
+ result.push_back(select_recursively(scope, *node.as_xml_node(),
+ selection_path));
+
+ index++;
+ }
+ }
+ return result;
+ }
+}
+
+value_t xpath_t::op_t::calc(scope_t& scope)
+{
+ bool find_all_nodes = false;
+
+ switch (kind) {
+ case VALUE:
+ return as_value();
+
+ case VAR_NAME:
+ case FUNC_NAME:
+ if (ptr_op_t reference = compile(scope)) {
+ return reference->calc(scope);
+ } else {
+ throw_(calc_error, "No " << (kind == VAR_NAME ? "variable" : "function")
+ << " named '" << as_string() << "'");
+ }
+ break;
+
+ case FUNCTION:
+ // This should never be evaluated directly; it only appears as the
+ // left node of an O_CALL operator.
+ assert(false);
+ break;
+
+ case O_CALL: {
+ call_scope_t call_args(scope);
+
+ if (right())
+ call_args.set_args(right()->calc(scope));
+
+ ptr_op_t func = left();
+ string name;
+
+ if (func->kind == FUNC_NAME) {
+ name = func->as_string();
+ func = func->compile(scope);
+ }
+
+ if (func->kind != FUNCTION)
+ throw_(calc_error,
+ name.empty() ? string("Attempt to call non-function") :
+ (string("Attempt to call unknown function '") + name + "'"));
+
+ return func->as_function()(call_args);
+ }
+
+ case ARG_INDEX: {
+ call_scope_t& args(CALL_SCOPE(scope));
+
+ if (as_long() >= 0 && as_long() < args.size())
+ return args[as_long()];
+ else
+ throw_(calc_error, "Reference to non-existing argument");
+ break;
+ }
+
+ case O_FIND:
+ case O_RFIND:
+ return select_nodes(scope, left()->calc(scope), right(), kind == O_RFIND);
+
+ case O_PRED: {
+ value_t values = left()->calc(scope);
+
+ if (! values.is_null()) {
+ op_predicate pred(right());
+
+ if (! values.is_sequence()) {
+ context_scope_t value_scope(scope, values, 0, 1);
+ if (pred(value_scope))
+ return values;
+ return NULL_VALUE;
+ } else {
+ std::size_t index = 0;
+ std::size_t size = values.as_sequence().size();
+
+ value_t result;
+
+ foreach (const value_t& value, values.as_sequence()) {
+ context_scope_t value_scope(scope, value, index, size);
+ if (pred(value_scope))
+ result.push_back(value);
+ index++;
+ }
+ return result;
+ }
+ }
+ break;
+ }
+
+ case NODE_ID:
+ switch (as_name()) {
+ case document_t::CURRENT:
+ return current_value(scope);
+
+ case document_t::PARENT:
+ if (optional<parent_node_t&> parent = current_xml_node(scope).parent())
+ return &*parent;
+ else
+ throw_(std::logic_error, "Attempt to access parent of root node");
+ break;
+
+ case document_t::ROOT:
+ return &current_xml_node(scope).document();
+
+ case document_t::ALL:
+ find_all_nodes = true;
+ break;
+
+ default:
+ break; // pass down to the NODE_NAME case
+ }
+ // fall through...
+
+ case NODE_NAME: {
+ node_t& current_node(current_xml_node(scope));
+
+ if (current_node.is_parent_node()) {
+ const bool have_name_id = kind == NODE_ID;
+
+ parent_node_t& parent(current_node.as_parent_node());
+
+ value_t result;
+ foreach (node_t * child, parent) {
+ if (find_all_nodes ||
+ ( have_name_id && as_name() == child->name_id()) ||
+ (! have_name_id && as_string() == child->name()))
+ result.push_back(child);
+ }
+ return result;
+ }
+ break;
+ }
+
+ case ATTR_ID:
+ case ATTR_NAME:
+ if (optional<value_t&> value =
+ kind == ATTR_ID ? current_xml_node(scope).get_attr(as_name()) :
+ current_xml_node(scope).get_attr(as_string()))
+ return *value;
+
+ break;
+
+ case O_NEQ:
+ return left()->calc(scope) != right()->calc(scope);
+ case O_EQ:
+ return left()->calc(scope) == right()->calc(scope);
+ case O_LT:
+ return left()->calc(scope) < right()->calc(scope);
+ case O_LTE:
+ return left()->calc(scope) <= right()->calc(scope);
+ case O_GT:
+ return left()->calc(scope) > right()->calc(scope);
+ case O_GTE:
+ return left()->calc(scope) >= right()->calc(scope);
+
+ case O_ADD:
+ return left()->calc(scope) + right()->calc(scope);
+ case O_SUB:
+ return left()->calc(scope) - right()->calc(scope);
+ case O_MUL:
+ return left()->calc(scope) * right()->calc(scope);
+ case O_DIV:
+ return left()->calc(scope) / right()->calc(scope);
+
+ case O_NEG:
+ assert(! right());
+ return left()->calc(scope).negate();
+
+ case O_NOT:
+ assert(! right());
+ return ! left()->calc(scope);
+
+ case O_AND:
+ return left()->calc(scope) && right()->calc(scope);
+ case O_OR:
+ return left()->calc(scope) || right()->calc(scope);
+
+ case O_COMMA:
+ case O_UNION: {
+ value_t result(left()->calc(scope));
+
+ ptr_op_t next = right();
+ while (next) {
+ ptr_op_t value_op;
+ if (next->kind == O_COMMA || next->kind == O_UNION) {
+ value_op = next->left();
+ next = next->right();
+ } else {
+ value_op = next;
+ next = NULL;
+ }
+
+ result.push_back(value_op->calc(scope));
+ }
+ return result;
+ }
+
+ case LAST:
+ default:
+ assert(false);
+ break;
+ }
+
+ return NULL_VALUE;
+}
+
+
+bool xpath_t::op_t::print(std::ostream& out, print_context_t& context) const
+{
+ bool found = false;
+
+ if (context.start_pos && this == context.op_to_find) {
+ *context.start_pos = (long)out.tellp() - 1;
+ found = true;
+ }
+
+ string symbol;
+
+ switch (kind) {
+ case VALUE: {
+ const value_t& value(as_value());
+ switch (value.type()) {
+ case value_t::VOID:
+ out << "<VOID>";
+ break;
+ case value_t::BOOLEAN:
+ if (value)
+ out << "1";
+ else
+ out << "0";
+ break;
+ case value_t::INTEGER:
+ out << value;
+ break;
+ case value_t::AMOUNT:
+ if (! context.relaxed)
+ out << '{';
+ out << value;
+ if (! context.relaxed)
+ out << '}';
+ break;
+ case value_t::BALANCE:
+ case value_t::BALANCE_PAIR:
+ assert(false);
+ break;
+ case value_t::DATETIME:
+ out << '[' << value << ']';
+ break;
+ case value_t::STRING:
+ out << '"' << value << '"';
+ break;
+
+ case value_t::XML_NODE:
+ out << '<' << value << '>';
+ break;
+ case value_t::POINTER:
+ out << '&' << value;
+ break;
+ case value_t::SEQUENCE:
+ out << '~' << value << '~';
+ break;
+ }
+ break;
+ }
+
+ case ATTR_ID:
+ out << '@';
+ // fall through...
+ case NODE_ID: {
+ context_scope_t& node_scope(CONTEXT_SCOPE(context.scope));
+ if (optional<const char *> name =
+ node_scope.xml_node().document().lookup_name(as_name()))
+ out << *name;
+ else
+ out << '#' << as_name();
+ break;
+ }
+
+ case NODE_NAME:
+ case FUNC_NAME:
+ out << as_string();
+ break;
+
+ case ATTR_NAME:
+ out << '@' << as_string();
+ break;
+
+ case VAR_NAME:
+ out << '$' << as_string();
+ break;
+
+ case FUNCTION:
+ out << "<FUNCTION>";
+ break;
+
+ case ARG_INDEX:
+ out << '@' << as_long();
+ break;
+
+ case O_NOT:
+ out << "!";
+ if (left() && left()->print(out, context))
+ found = true;
+ break;
+ case O_NEG:
+ out << "-";
+ if (left() && left()->print(out, context))
+ found = true;
+ break;
+
+ case O_UNION:
+ if (left() && left()->print(out, context))
+ found = true;
+ out << " | ";
+ if (right() && right()->print(out, context))
+ found = true;
+ break;
+
+ case O_ADD:
+ out << "(";
+ if (left() && left()->print(out, context))
+ found = true;
+ out << " + ";
+ if (right() && right()->print(out, context))
+ found = true;
+ out << ")";
+ break;
+ case O_SUB:
+ out << "(";
+ if (left() && left()->print(out, context))
+ found = true;
+ out << " - ";
+ if (right() && right()->print(out, context))
+ found = true;
+ out << ")";
+ break;
+ case O_MUL:
+ out << "(";
+ if (left() && left()->print(out, context))
+ found = true;
+ out << " * ";
+ if (right() && right()->print(out, context))
+ found = true;
+ out << ")";
+ break;
+ case O_DIV:
+ out << "(";
+ if (left() && left()->print(out, context))
+ found = true;
+ out << " / ";
+ if (right() && right()->print(out, context))
+ found = true;
+ out << ")";
+ break;
+
+ case O_NEQ:
+ out << "(";
+ if (left() && left()->print(out, context))
+ found = true;
+ out << " != ";
+ if (right() && right()->print(out, context))
+ found = true;
+ out << ")";
+ break;
+ case O_EQ:
+ out << "(";
+ if (left() && left()->print(out, context))
+ found = true;
+ out << " == ";
+ if (right() && right()->print(out, context))
+ found = true;
+ out << ")";
+ break;
+ case O_LT:
+ out << "(";
+ if (left() && left()->print(out, context))
+ found = true;
+ out << " < ";
+ if (right() && right()->print(out, context))
+ found = true;
+ out << ")";
+ break;
+ case O_LTE:
+ out << "(";
+ if (left() && left()->print(out, context))
+ found = true;
+ out << " <= ";
+ if (right() && right()->print(out, context))
+ found = true;
+ out << ")";
+ break;
+ case O_GT:
+ out << "(";
+ if (left() && left()->print(out, context))
+ found = true;
+ out << " > ";
+ if (right() && right()->print(out, context))
+ found = true;
+ out << ")";
+ break;
+ case O_GTE:
+ out << "(";
+ if (left() && left()->print(out, context))
+ found = true;
+ out << " >= ";
+ if (right() && right()->print(out, context))
+ found = true;
+ out << ")";
+ break;
+
+ case O_AND:
+ out << "(";
+ if (left() && left()->print(out, context))
+ found = true;
+ out << " & ";
+ if (right() && right()->print(out, context))
+ found = true;
+ out << ")";
+ break;
+ case O_OR:
+ out << "(";
+ if (left() && left()->print(out, context))
+ found = true;
+ out << " | ";
+ if (right() && right()->print(out, context))
+ found = true;
+ out << ")";
+ break;
+
+ case O_COMMA:
+ if (left() && left()->print(out, context))
+ found = true;
+ out << ", ";
+ if (right() && right()->print(out, context))
+ found = true;
+ break;
+
+ case O_CALL:
+ if (left() && left()->print(out, context))
+ found = true;
+ out << "(";
+ if (right() && right()->print(out, context))
+ found = true;
+ out << ")";
+ break;
+
+ case O_FIND:
+ if (left() && left()->print(out, context))
+ found = true;
+ out << "/";
+ if (right() && right()->print(out, context))
+ found = true;
+ break;
+ case O_RFIND:
+ if (left() && left()->print(out, context))
+ found = true;
+ out << "//";
+ if (right() && right()->print(out, context))
+ found = true;
+ break;
+ case O_PRED:
+ if (left() && left()->print(out, context))
+ found = true;
+ out << "[";
+ if (right() && right()->print(out, context))
+ found = true;
+ out << "]";
+ break;
+
+ case LAST:
+ default:
+ assert(false);
+ break;
+ }
+
+ if (! symbol.empty()) {
+ if (amount_t::current_pool->find(symbol))
+ out << '@';
+ out << symbol;
+ }
+
+ if (context.end_pos && this == context.op_to_find)
+ *context.end_pos = (long)out.tellp() - 1;
+
+ return found;
+}
+
+void xpath_t::op_t::dump(std::ostream& out, const int depth) const
+{
+ out.setf(std::ios::left);
+ out.width(10);
+ out << this << " ";
+
+ for (int i = 0; i < depth; i++)
+ out << " ";
+
+ switch (kind) {
+ case VALUE:
+ out << "VALUE - " << as_value();
+ break;
+
+ case NODE_NAME:
+ out << "NODE_NAME - " << as_string();
+ break;
+ case NODE_ID:
+ out << "NODE_ID - " << as_name();
+ break;
+
+ case ATTR_NAME:
+ out << "ATTR_NAME - " << as_string();
+ break;
+ case ATTR_ID:
+ out << "ATTR_ID - " << as_name();
+ break;
+
+ case FUNC_NAME:
+ out << "FUNC_NAME - " << as_string();
+ break;
+
+ case VAR_NAME:
+ out << "VAR_NAME - " << as_string();
+ break;
+
+ case ARG_INDEX:
+ out << "ARG_INDEX - " << as_long();
+ break;
+
+ case FUNCTION:
+ out << "FUNCTION";
+ break;
+
+ case O_CALL: out << "O_CALL"; break;
+
+ case O_NOT: out << "O_NOT"; break;
+ case O_NEG: out << "O_NEG"; break;
+
+ case O_UNION: out << "O_UNION"; break;
+
+ case O_ADD: out << "O_ADD"; break;
+ case O_SUB: out << "O_SUB"; break;
+ case O_MUL: out << "O_MUL"; break;
+ case O_DIV: out << "O_DIV"; break;
+
+ case O_NEQ: out << "O_NEQ"; break;
+ case O_EQ: out << "O_EQ"; break;
+ case O_LT: out << "O_LT"; break;
+ case O_LTE: out << "O_LTE"; break;
+ case O_GT: out << "O_GT"; break;
+ case O_GTE: out << "O_GTE"; break;
+
+ case O_AND: out << "O_AND"; break;
+ case O_OR: out << "O_OR"; break;
+
+ case O_COMMA: out << "O_COMMA"; break;
+
+ case O_FIND: out << "O_FIND"; break;
+ case O_RFIND: out << "O_RFIND"; break;
+ case O_PRED: out << "O_PRED"; break;
+
+ case LAST:
+ default:
+ assert(false);
+ break;
+ }
+
+ out << " (" << refc << ')' << std::endl;
+
+ if (kind > TERMINALS) {
+ if (left()) {
+ left()->dump(out, depth + 1);
+ if (right())
+ right()->dump(out, depth + 1);
+ } else {
+ assert(! right());
+ }
+ }
+}
+
+} // namespace xml
+
+
+value_t xml_command(xml::xpath_t::call_scope_t& args)
+{
+ assert(args.size() == 0);
+
+ value_t ostream = args.resolve("ostream");
+ std::ostream& outs(ostream.as_ref_lval<std::ostream>());
+
+ xml::xpath_t::context_scope_t& node_context(CONTEXT_SCOPE(args));
+ node_context.xml_node().print(outs);
+
+ return true;
+}
+
+} // namespace ledger
generated by cgit v1.2.3 (git 2.39.1) at 2025-01-10 12:47:36 +0000