/* -*- mode: C; c-file-style: "gnu" -*- */ /* dbus-marshal-recursive.c Marshalling routines for recursive types * * Copyright (C) 2004, 2005 Red Hat, Inc. * * Licensed under the Academic Free License version 2.1 * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA * */ #include "dbus-marshal-recursive.h" #include "dbus-marshal-basic.h" #include "dbus-signature.h" #include "dbus-internals.h" /** * @addtogroup DBusMarshal * @{ */ /** turn this on to get deluged in TypeReader verbose spam */ #define RECURSIVE_MARSHAL_READ_TRACE 0 /** turn this on to get deluged in TypeWriter verbose spam */ #define RECURSIVE_MARSHAL_WRITE_TRACE 0 static void free_fixups (DBusList **fixups) { DBusList *link; link = _dbus_list_get_first_link (fixups); while (link != NULL) { DBusList *next; next = _dbus_list_get_next_link (fixups, link); dbus_free (link->data); _dbus_list_free_link (link); link = next; } *fixups = NULL; } static void apply_and_free_fixups (DBusList **fixups, DBusTypeReader *reader) { DBusList *link; #if RECURSIVE_MARSHAL_WRITE_TRACE if (*fixups) _dbus_verbose (" %d FIXUPS to apply\n", _dbus_list_get_length (fixups)); #endif link = _dbus_list_get_first_link (fixups); while (link != NULL) { DBusList *next; next = _dbus_list_get_next_link (fixups, link); if (reader) { DBusArrayLenFixup *f; f = link->data; #if RECURSIVE_MARSHAL_WRITE_TRACE _dbus_verbose (" applying FIXUP to reader %p at pos %d new_len = %d old len %d\n", reader, f->len_pos_in_reader, f->new_len, _dbus_marshal_read_uint32 (reader->value_str, f->len_pos_in_reader, reader->byte_order, NULL)); #endif _dbus_marshal_set_uint32 ((DBusString*) reader->value_str, f->len_pos_in_reader, f->new_len, reader->byte_order); } dbus_free (link->data); _dbus_list_free_link (link); link = next; } *fixups = NULL; } /** * Virtual table for a type reader. */ struct DBusTypeReaderClass { const char *name; /**< name for debugging */ int id; /**< index in all_reader_classes */ dbus_bool_t types_only; /**< only iterates over types, not values */ void (* recurse) (DBusTypeReader *sub, DBusTypeReader *parent); /**< recurse with this reader as sub */ dbus_bool_t (* check_finished) (const DBusTypeReader *reader); /**< check whether reader is at the end */ void (* next) (DBusTypeReader *reader, int current_type); /**< go to the next value */ void (* init_from_mark) (DBusTypeReader *reader, const DBusTypeMark *mark); /**< uncompress from a mark */ }; static int element_type_get_alignment (const DBusString *str, int pos) { return _dbus_type_get_alignment (_dbus_first_type_in_signature (str, pos)); } static void reader_init (DBusTypeReader *reader, int byte_order, const DBusString *type_str, int type_pos, const DBusString *value_str, int value_pos) { reader->byte_order = byte_order; reader->finished = FALSE; reader->type_str = type_str; reader->type_pos = type_pos; reader->value_str = value_str; reader->value_pos = value_pos; } static void base_reader_recurse (DBusTypeReader *sub, DBusTypeReader *parent) { /* point subreader at the same place as parent */ reader_init (sub, parent->byte_order, parent->type_str, parent->type_pos, parent->value_str, parent->value_pos); } static void struct_or_dict_entry_types_only_reader_recurse (DBusTypeReader *sub, DBusTypeReader *parent) { base_reader_recurse (sub, parent); _dbus_assert (_dbus_string_get_byte (sub->type_str, sub->type_pos) == DBUS_STRUCT_BEGIN_CHAR || _dbus_string_get_byte (sub->type_str, sub->type_pos) == DBUS_DICT_ENTRY_BEGIN_CHAR); sub->type_pos += 1; } static void struct_or_dict_entry_reader_recurse (DBusTypeReader *sub, DBusTypeReader *parent) { struct_or_dict_entry_types_only_reader_recurse (sub, parent); /* struct and dict entry have 8 byte alignment */ sub->value_pos = _DBUS_ALIGN_VALUE (sub->value_pos, 8); } static void array_types_only_reader_recurse (DBusTypeReader *sub, DBusTypeReader *parent) { base_reader_recurse (sub, parent); /* point type_pos at the array element type */ sub->type_pos += 1; /* Init with values likely to crash things if misused */ sub->u.array.start_pos = _DBUS_INT_MAX; sub->array_len_offset = 7; } /** compute position of array length given array_len_offset, which is the offset back from start_pos to end of the len */ #define ARRAY_READER_LEN_POS(reader) \ ((reader)->u.array.start_pos - ((int)(reader)->array_len_offset) - 4) static int array_reader_get_array_len (const DBusTypeReader *reader) { dbus_uint32_t array_len; int len_pos; len_pos = ARRAY_READER_LEN_POS (reader); _dbus_assert (_DBUS_ALIGN_VALUE (len_pos, 4) == (unsigned) len_pos); array_len = _dbus_unpack_uint32 (reader->byte_order, _dbus_string_get_const_data_len (reader->value_str, len_pos, 4)); #if RECURSIVE_MARSHAL_READ_TRACE _dbus_verbose (" reader %p len_pos %d array len %u len_offset %d\n", reader, len_pos, array_len, reader->array_len_offset); #endif _dbus_assert (reader->u.array.start_pos - len_pos - 4 < 8); return array_len; } static void array_reader_recurse (DBusTypeReader *sub, DBusTypeReader *parent) { int alignment; int len_pos; array_types_only_reader_recurse (sub, parent); sub->value_pos = _DBUS_ALIGN_VALUE (sub->value_pos, 4); len_pos = sub->value_pos; sub->value_pos += 4; /* for the length */ alignment = element_type_get_alignment (sub->type_str, sub->type_pos); sub->value_pos = _DBUS_ALIGN_VALUE (sub->value_pos, alignment); sub->u.array.start_pos = sub->value_pos; _dbus_assert ((sub->u.array.start_pos - (len_pos + 4)) < 8); /* only 3 bits in array_len_offset */ sub->array_len_offset = sub->u.array.start_pos - (len_pos + 4); #if RECURSIVE_MARSHAL_READ_TRACE _dbus_verbose (" type reader %p array start = %d len_offset = %d array len = %d array element type = %s\n", sub, sub->u.array.start_pos, sub->array_len_offset, array_reader_get_array_len (sub), _dbus_type_to_string (_dbus_first_type_in_signature (sub->type_str, sub->type_pos))); #endif } static void variant_reader_recurse (DBusTypeReader *sub, DBusTypeReader *parent) { int sig_len; int contained_alignment; base_reader_recurse (sub, parent); /* Variant is 1 byte sig length (without nul), signature with nul, * padding to 8-boundary, then values */ sig_len = _dbus_string_get_byte (sub->value_str, sub->value_pos); sub->type_str = sub->value_str; sub->type_pos = sub->value_pos + 1; sub->value_pos = sub->type_pos + sig_len + 1; contained_alignment = _dbus_type_get_alignment (_dbus_first_type_in_signature (sub->type_str, sub->type_pos)); sub->value_pos = _DBUS_ALIGN_VALUE (sub->value_pos, contained_alignment); #if RECURSIVE_MARSHAL_READ_TRACE _dbus_verbose (" type reader %p variant containing '%s'\n", sub, _dbus_string_get_const_data_len (sub->type_str, sub->type_pos, 0)); #endif } static dbus_bool_t array_reader_check_finished (const DBusTypeReader *reader) { int end_pos; /* return the array element type if elements remain, and * TYPE_INVALID otherwise */ end_pos = reader->u.array.start_pos + array_reader_get_array_len (reader); _dbus_assert (reader->value_pos <= end_pos); _dbus_assert (reader->value_pos >= reader->u.array.start_pos); return reader->value_pos == end_pos; } static void skip_one_complete_type (const DBusString *type_str, int *type_pos) { _dbus_type_signature_next (_dbus_string_get_const_data (type_str), type_pos); } /** * Skips to the next "complete" type inside a type signature. * The signature is read starting at type_pos, and the next * type position is stored in the same variable. * * @param type_str a type signature (must be valid) * @param type_pos an integer position in the type signtaure (in and out) */ void _dbus_type_signature_next (const char *type_str, int *type_pos) { const unsigned char *p; const unsigned char *start; _dbus_assert (type_str != NULL); _dbus_assert (type_pos != NULL); start = type_str; p = start + *type_pos; _dbus_assert (*p != DBUS_STRUCT_END_CHAR); _dbus_assert (*p != DBUS_DICT_ENTRY_END_CHAR); while (*p == DBUS_TYPE_ARRAY) ++p; _dbus_assert (*p != DBUS_STRUCT_END_CHAR); _dbus_assert (*p != DBUS_DICT_ENTRY_END_CHAR); if (*p == DBUS_STRUCT_BEGIN_CHAR) { int depth; depth = 1; while (TRUE) { _dbus_assert (*p != DBUS_TYPE_INVALID); ++p; _dbus_assert (*p != DBUS_TYPE_INVALID); if (*p == DBUS_STRUCT_BEGIN_CHAR) depth += 1; else if (*p == DBUS_STRUCT_END_CHAR) { depth -= 1; if (depth == 0) { ++p; break; } } } } else if (*p == DBUS_DICT_ENTRY_BEGIN_CHAR) { int depth; depth = 1; while (TRUE) { _dbus_assert (*p != DBUS_TYPE_INVALID); ++p; _dbus_assert (*p != DBUS_TYPE_INVALID); if (*p == DBUS_DICT_ENTRY_BEGIN_CHAR) depth += 1; else if (*p == DBUS_DICT_ENTRY_END_CHAR) { depth -= 1; if (depth == 0) { ++p; break; } } } } else { ++p; } *type_pos = (int) (p - start); } static int find_len_of_complete_type (const DBusString *type_str, int type_pos) { int end; end = type_pos; skip_one_complete_type (type_str, &end); return end - type_pos; } static void base_reader_next (DBusTypeReader *reader, int current_type) { switch (current_type) { case DBUS_TYPE_DICT_ENTRY: case DBUS_TYPE_STRUCT: case DBUS_TYPE_VARIANT: /* Scan forward over the entire container contents */ { DBusTypeReader sub; if (reader->klass->types_only && current_type == DBUS_TYPE_VARIANT) ; else { /* Recurse into the struct or variant */ _dbus_type_reader_recurse (reader, &sub); /* Skip everything in this subreader */ while (_dbus_type_reader_next (&sub)) { /* nothing */; } } if (!reader->klass->types_only) reader->value_pos = sub.value_pos; /* Now we are at the end of this container; for variants, the * subreader's type_pos is totally inapplicable (it's in the * value string) but we know that we increment by one past the * DBUS_TYPE_VARIANT */ if (current_type == DBUS_TYPE_VARIANT) reader->type_pos += 1; else reader->type_pos = sub.type_pos; } break; case DBUS_TYPE_ARRAY: { if (!reader->klass->types_only) _dbus_marshal_skip_array (reader->value_str, _dbus_first_type_in_signature (reader->type_str, reader->type_pos + 1), reader->byte_order, &reader->value_pos); skip_one_complete_type (reader->type_str, &reader->type_pos); } break; default: if (!reader->klass->types_only) _dbus_marshal_skip_basic (reader->value_str, current_type, reader->byte_order, &reader->value_pos); reader->type_pos += 1; break; } } static void struct_reader_next (DBusTypeReader *reader, int current_type) { int t; base_reader_next (reader, current_type); /* for STRUCT containers we return FALSE at the end of the struct, * for INVALID we return FALSE at the end of the signature. * In both cases we arrange for get_current_type() to return INVALID * which is defined to happen iff we're at the end (no more next()) */ t = _dbus_string_get_byte (reader->type_str, reader->type_pos); if (t == DBUS_STRUCT_END_CHAR) { reader->type_pos += 1; reader->finished = TRUE; } } static void dict_entry_reader_next (DBusTypeReader *reader, int current_type) { int t; base_reader_next (reader, current_type); /* for STRUCT containers we return FALSE at the end of the struct, * for INVALID we return FALSE at the end of the signature. * In both cases we arrange for get_current_type() to return INVALID * which is defined to happen iff we're at the end (no more next()) */ t = _dbus_string_get_byte (reader->type_str, reader->type_pos); if (t == DBUS_DICT_ENTRY_END_CHAR) { reader->type_pos += 1; reader->finished = TRUE; } } static void array_types_only_reader_next (DBusTypeReader *reader, int current_type) { /* We have one "element" to be iterated over * in each array, which is its element type. * So the finished flag indicates whether we've * iterated over it yet or not. */ reader->finished = TRUE; } static void array_reader_next (DBusTypeReader *reader, int current_type) { /* Skip one array element */ int end_pos; end_pos = reader->u.array.start_pos + array_reader_get_array_len (reader); #if RECURSIVE_MARSHAL_READ_TRACE _dbus_verbose (" reader %p array next START start_pos = %d end_pos = %d value_pos = %d current_type = %s\n", reader, reader->u.array.start_pos, end_pos, reader->value_pos, _dbus_type_to_string (current_type)); #endif _dbus_assert (reader->value_pos < end_pos); _dbus_assert (reader->value_pos >= reader->u.array.start_pos); switch (_dbus_first_type_in_signature (reader->type_str, reader->type_pos)) { case DBUS_TYPE_DICT_ENTRY: case DBUS_TYPE_STRUCT: case DBUS_TYPE_VARIANT: { DBusTypeReader sub; /* Recurse into the struct or variant */ _dbus_type_reader_recurse (reader, &sub); /* Skip everything in this element */ while (_dbus_type_reader_next (&sub)) { /* nothing */; } /* Now we are at the end of this element */ reader->value_pos = sub.value_pos; } break; case DBUS_TYPE_ARRAY: { _dbus_marshal_skip_array (reader->value_str, _dbus_first_type_in_signature (reader->type_str, reader->type_pos + 1), reader->byte_order, &reader->value_pos); } break; default: { _dbus_marshal_skip_basic (reader->value_str, current_type, reader->byte_order, &reader->value_pos); } break; } #if RECURSIVE_MARSHAL_READ_TRACE _dbus_verbose (" reader %p array next END start_pos = %d end_pos = %d value_pos = %d current_type = %s\n", reader, reader->u.array.start_pos, end_pos, reader->value_pos, _dbus_type_to_string (current_type)); #endif _dbus_assert (reader->value_pos <= end_pos); if (reader->value_pos == end_pos) { skip_one_complete_type (reader->type_str, &reader->type_pos); } } static void array_init_from_mark (DBusTypeReader *reader, const DBusTypeMark *mark) { /* Fill in the array-specific fields from the mark. The general * fields are already filled in. */ reader->u.array.start_pos = mark->array_start_pos; reader->array_len_offset = mark->array_len_offset; } static const DBusTypeReaderClass body_reader_class = { "body", 0, FALSE, NULL, /* body is always toplevel, so doesn't get recursed into */ NULL, base_reader_next, NULL }; static const DBusTypeReaderClass body_types_only_reader_class = { "body types", 1, TRUE, NULL, /* body is always toplevel, so doesn't get recursed into */ NULL, base_reader_next, NULL }; static const DBusTypeReaderClass struct_reader_class = { "struct", 2, FALSE, struct_or_dict_entry_reader_recurse, NULL, struct_reader_next, NULL }; static const DBusTypeReaderClass struct_types_only_reader_class = { "struct types", 3, TRUE, struct_or_dict_entry_types_only_reader_recurse, NULL, struct_reader_next, NULL }; static const DBusTypeReaderClass dict_entry_reader_class = { "dict_entry", 4, FALSE, struct_or_dict_entry_reader_recurse, NULL, dict_entry_reader_next, NULL }; static const DBusTypeReaderClass dict_entry_types_only_reader_class = { "dict_entry types", 5, TRUE, struct_or_dict_entry_types_only_reader_recurse, NULL, dict_entry_reader_next, NULL }; static const DBusTypeReaderClass array_reader_class = { "array", 6, FALSE, array_reader_recurse, array_reader_check_finished, array_reader_next, array_init_from_mark }; static const DBusTypeReaderClass array_types_only_reader_class = { "array types", 7, TRUE, array_types_only_reader_recurse, NULL, array_types_only_reader_next, NULL }; static const DBusTypeReaderClass variant_reader_class = { "variant", 8, FALSE, variant_reader_recurse, NULL, base_reader_next, NULL }; static const DBusTypeReaderClass const * all_reader_classes[] = { &body_reader_class, &body_types_only_reader_class, &struct_reader_class, &struct_types_only_reader_class, &dict_entry_reader_class, &dict_entry_types_only_reader_class, &array_reader_class, &array_types_only_reader_class, &variant_reader_class }; /** * Initializes a type reader. * * @param reader the reader * @param byte_order the byte order of the block to read * @param type_str the signature of the block to read * @param type_pos location of signature * @param value_str the string containing values block * @param value_pos start of values block */ void _dbus_type_reader_init (DBusTypeReader *reader, int byte_order, const DBusString *type_str, int type_pos, const DBusString *value_str, int value_pos) { reader->klass = &body_reader_class; reader_init (reader, byte_order, type_str, type_pos, value_str, value_pos); #if RECURSIVE_MARSHAL_READ_TRACE _dbus_verbose (" type reader %p init type_pos = %d value_pos = %d remaining sig '%s'\n", reader, reader->type_pos, reader->value_pos, _dbus_string_get_const_data_len (reader->type_str, reader->type_pos, 0)); #endif } /** * Initializes a type reader that's been compressed into a * DBusTypeMark. The args have to be the same as those passed in to * create the original #DBusTypeReader. * * @param reader the reader * @param byte_order the byte order of the value block * @param type_str string containing the type signature * @param value_str string containing the values block * @param mark the mark to decompress from */ void _dbus_type_reader_init_from_mark (DBusTypeReader *reader, int byte_order, const DBusString *type_str, const DBusString *value_str, const DBusTypeMark *mark) { reader->klass = all_reader_classes[mark->container_type]; reader_init (reader, byte_order, mark->type_pos_in_value_str ? value_str : type_str, mark->type_pos, value_str, mark->value_pos); if (reader->klass->init_from_mark) (* reader->klass->init_from_mark) (reader, mark); #if RECURSIVE_MARSHAL_READ_TRACE _dbus_verbose (" type reader %p init from mark type_pos = %d value_pos = %d remaining sig '%s'\n", reader, reader->type_pos, reader->value_pos, _dbus_string_get_const_data_len (reader->type_str, reader->type_pos, 0)); #endif } /** * Like _dbus_type_reader_init() but the iteration is over the * signature, not over values. * * @param reader the reader * @param type_str the signature string * @param type_pos location in the signature string */ void _dbus_type_reader_init_types_only (DBusTypeReader *reader, const DBusString *type_str, int type_pos) { reader->klass = &body_types_only_reader_class; reader_init (reader, DBUS_COMPILER_BYTE_ORDER /* irrelevant */, type_str, type_pos, NULL, _DBUS_INT_MAX /* crashes if we screw up */); #if RECURSIVE_MARSHAL_READ_TRACE _dbus_verbose (" type reader %p init types only type_pos = %d remaining sig '%s'\n", reader, reader->type_pos, _dbus_string_get_const_data_len (reader->type_str, reader->type_pos, 0)); #endif } /** * Like _dbus_type_reader_init_from_mark() but only iterates over * the signature, not the values. * * @param reader the reader * @param type_str the signature string * @param mark the mark to decompress from */ void _dbus_type_reader_init_types_only_from_mark (DBusTypeReader *reader, const DBusString *type_str, const DBusTypeMark *mark) { reader->klass = all_reader_classes[mark->container_type]; _dbus_assert (reader->klass->types_only); _dbus_assert (!mark->type_pos_in_value_str); reader_init (reader, DBUS_COMPILER_BYTE_ORDER, /* irrelevant */ type_str, mark->type_pos, NULL, _DBUS_INT_MAX /* crashes if we screw up */); if (reader->klass->init_from_mark) (* reader->klass->init_from_mark) (reader, mark); #if RECURSIVE_MARSHAL_READ_TRACE _dbus_verbose (" type reader %p init types only from mark type_pos = %d remaining sig '%s'\n", reader, reader->type_pos, _dbus_string_get_const_data_len (reader->type_str, reader->type_pos, 0)); #endif } /** * Compresses a type reader into a #DBusTypeMark, useful for example * if you want to cache a bunch of positions in a block of values. * * @param reader the reader * @param mark the mark to init */ void _dbus_type_reader_save_mark (const DBusTypeReader *reader, DBusTypeMark *mark) { mark->type_pos_in_value_str = (reader->type_str == reader->value_str); mark->container_type = reader->klass->id; _dbus_assert (all_reader_classes[reader->klass->id] == reader->klass); mark->type_pos = reader->type_pos; mark->value_pos = reader->value_pos; /* these are just junk if the reader isn't really an array of course */ mark->array_len_offset = reader->array_len_offset; mark->array_start_pos = reader->u.array.start_pos; } /** * Gets the type of the value the reader is currently pointing to; * or for a types-only reader gets the type it's currently pointing to. * If the reader is at the end of a block or end of a container such * as an array, returns #DBUS_TYPE_INVALID. * * @param reader the reader */ int _dbus_type_reader_get_current_type (const DBusTypeReader *reader) { int t; if (reader->finished || (reader->klass->check_finished && (* reader->klass->check_finished) (reader))) t = DBUS_TYPE_INVALID; else t = _dbus_first_type_in_signature (reader->type_str, reader->type_pos); _dbus_assert (t != DBUS_STRUCT_END_CHAR); _dbus_assert (t != DBUS_STRUCT_BEGIN_CHAR); _dbus_assert (t != DBUS_DICT_ENTRY_END_CHAR); _dbus_assert (t != DBUS_DICT_ENTRY_BEGIN_CHAR); #if 0 _dbus_verbose (" type reader %p current type_pos = %d type = %s\n", reader, reader->type_pos, _dbus_type_to_string (t)); #endif return t; } /** * Gets the type of an element of the array the reader is currently * pointing to. It's an error to call this if * _dbus_type_reader_get_current_type() doesn't return #DBUS_TYPE_ARRAY * for this reader. * * @param reader the reader */ int _dbus_type_reader_get_element_type (const DBusTypeReader *reader) { int element_type; _dbus_assert (_dbus_type_reader_get_current_type (reader) == DBUS_TYPE_ARRAY); element_type = _dbus_first_type_in_signature (reader->type_str, reader->type_pos + 1); return element_type; } /** * Gets the current position in the value block * @param reader the reader */ int _dbus_type_reader_get_value_pos (const DBusTypeReader *reader) { return reader->value_pos; } /** * Get the address of the marshaled value in the data being read. The * address may not be aligned; you have to align it to the type of the * value you want to read. Most of the demarshal routines do this for * you. * * @param reader the reader * @param value_location the address of the marshaled value */ void _dbus_type_reader_read_raw (const DBusTypeReader *reader, const unsigned char **value_location) { _dbus_assert (!reader->klass->types_only); *value_location = _dbus_string_get_const_data_len (reader->value_str, reader->value_pos, 0); } /** * Reads a basic-typed value, as with _dbus_marshal_read_basic(). * * @param reader the reader * @param value the address of the value */ void _dbus_type_reader_read_basic (const DBusTypeReader *reader, void *value) { int t; _dbus_assert (!reader->klass->types_only); t = _dbus_type_reader_get_current_type (reader); _dbus_marshal_read_basic (reader->value_str, reader->value_pos, t, value, reader->byte_order, NULL); #if RECURSIVE_MARSHAL_READ_TRACE _dbus_verbose (" type reader %p read basic type_pos = %d value_pos = %d remaining sig '%s'\n", reader, reader->type_pos, reader->value_pos, _dbus_string_get_const_data_len (reader->type_str, reader->type_pos, 0)); #endif } /** * Returns the number of values remaining in the current array reader. * * @param reader the reader to read from * @returns the number of elements remaining in the array */ int _dbus_type_reader_get_array_length (const DBusTypeReader *reader) { _dbus_assert (!reader->klass->types_only); _dbus_assert (reader->klass == &array_reader_class); return array_reader_get_array_len (reader); } /** * Reads a block of fixed-length basic values, from the current point * in an array to the end of the array. Does not work for arrays of * string or container types. * * This function returns the array in-place; it does not make a copy, * and it does not swap the bytes. * * If you ask for #DBUS_TYPE_DOUBLE you will get a "const double*" back * and the "value" argument should be a "const double**" and so on. * * @param reader the reader to read from * @param value place to return the array values * @param n_elements place to return number of array elements */ void _dbus_type_reader_read_fixed_multi (const DBusTypeReader *reader, void *value, int *n_elements) { int element_type; int end_pos; int remaining_len; int alignment; int total_len; _dbus_assert (!reader->klass->types_only); _dbus_assert (reader->klass == &array_reader_class); element_type = _dbus_first_type_in_signature (reader->type_str, reader->type_pos); _dbus_assert (element_type != DBUS_TYPE_INVALID); /* why we don't use get_current_type() */ _dbus_assert (dbus_type_is_fixed (element_type)); alignment = _dbus_type_get_alignment (element_type); _dbus_assert (reader->value_pos >= reader->u.array.start_pos); total_len = array_reader_get_array_len (reader); end_pos = reader->u.array.start_pos + total_len; remaining_len = end_pos - reader->value_pos; #if RECURSIVE_MARSHAL_READ_TRACE _dbus_verbose ("end_pos %d total_len %d remaining_len %d value_pos %d\n", end_pos, total_len, remaining_len, reader->value_pos); #endif _dbus_assert (remaining_len <= total_len); if (remaining_len == 0) *(const DBusBasicValue**) value = NULL; else *(const DBusBasicValue**) value = (void*) _dbus_string_get_const_data_len (reader->value_str, reader->value_pos, remaining_len); *n_elements = remaining_len / alignment; _dbus_assert ((remaining_len % alignment) == 0); #if RECURSIVE_MARSHAL_READ_TRACE _dbus_verbose (" type reader %p read fixed array type_pos = %d value_pos = %d remaining sig '%s'\n", reader, reader->type_pos, reader->value_pos, _dbus_string_get_const_data_len (reader->type_str, reader->type_pos, 0)); #endif } /** * Initialize a new reader pointing to the first type and * corresponding value that's a child of the current container. It's * an error to call this if the current type is a non-container. * * Note that DBusTypeReader traverses values, not types. So if you * have an empty array of array of int, you can't recurse into it. You * can only recurse into each element. * * @param reader the reader * @param sub a reader to init pointing to the first child */ void _dbus_type_reader_recurse (DBusTypeReader *reader, DBusTypeReader *sub) { int t; t = _dbus_first_type_in_signature (reader->type_str, reader->type_pos); switch (t) { case DBUS_TYPE_STRUCT: if (reader->klass->types_only) sub->klass = &struct_types_only_reader_class; else sub->klass = &struct_reader_class; break; case DBUS_TYPE_DICT_ENTRY: if (reader->klass->types_only) sub->klass = &dict_entry_types_only_reader_class; else sub->klass = &dict_entry_reader_class; break; case DBUS_TYPE_ARRAY: if (reader->klass->types_only) sub->klass = &array_types_only_reader_class; else sub->klass = &array_reader_class; break; case DBUS_TYPE_VARIANT: if (reader->klass->types_only) _dbus_assert_not_reached ("can't recurse into variant typecode"); else sub->klass = &variant_reader_class; break; default: _dbus_verbose ("recursing into type %s\n", _dbus_type_to_string (t)); #ifndef DBUS_DISABLE_CHECKS if (t == DBUS_TYPE_INVALID) _dbus_warn ("You can't recurse into an empty array or off the end of a message body\n"); #endif /* DBUS_DISABLE_CHECKS */ _dbus_assert_not_reached ("don't yet handle recursing into this type"); } _dbus_assert (sub->klass == all_reader_classes[sub->klass->id]); (* sub->klass->recurse) (sub, reader); #if RECURSIVE_MARSHAL_READ_TRACE _dbus_verbose (" type reader %p RECURSED type_pos = %d value_pos = %d remaining sig '%s'\n", sub, sub->type_pos, sub->value_pos, _dbus_string_get_const_data_len (sub->type_str, sub->type_pos, 0)); #endif } /** * Skip to the next value on this "level". e.g. the next field in a * struct, the next value in an array. Returns FALSE at the end of the * current container. * * @param reader the reader * @returns FALSE if nothing more to read at or below this level */ dbus_bool_t _dbus_type_reader_next (DBusTypeReader *reader) { int t; t = _dbus_type_reader_get_current_type (reader); #if RECURSIVE_MARSHAL_READ_TRACE _dbus_verbose (" type reader %p START next() { type_pos = %d value_pos = %d remaining sig '%s' current_type = %s\n", reader, reader->type_pos, reader->value_pos, _dbus_string_get_const_data_len (reader->type_str, reader->type_pos, 0), _dbus_type_to_string (t)); #endif if (t == DBUS_TYPE_INVALID) return FALSE; (* reader->klass->next) (reader, t); #if RECURSIVE_MARSHAL_READ_TRACE _dbus_verbose (" type reader %p END next() type_pos = %d value_pos = %d remaining sig '%s' current_type = %s\n", reader, reader->type_pos, reader->value_pos, _dbus_string_get_const_data_len (reader->type_str, reader->type_pos, 0), _dbus_type_to_string (_dbus_type_reader_get_current_type (reader))); #endif return _dbus_type_reader_get_current_type (reader) != DBUS_TYPE_INVALID; } /** * Check whether there's another value on this "level". e.g. the next * field in a struct, the next value in an array. Returns FALSE at the * end of the current container. * * You probably don't want to use this; it makes for an awkward for/while * loop. A nicer one is "while ((current_type = get_current_type()) != INVALID)" * * @param reader the reader * @returns FALSE if nothing more to read at or below this level */ dbus_bool_t _dbus_type_reader_has_next (const DBusTypeReader *reader) { /* Not efficient but works for now. */ DBusTypeReader copy; copy = *reader; return _dbus_type_reader_next (©); } /** * Gets the string and range of said string containing the signature * of the current value. Essentially a more complete version of * _dbus_type_reader_get_current_type() (returns the full type * rather than only the outside of the onion). * * Note though that the first byte in a struct signature is * #DBUS_STRUCT_BEGIN_CHAR while the current type will be * #DBUS_TYPE_STRUCT so it isn't true that the first byte of the * signature is always the same as the current type. Another * difference is that this function will still return a signature when * inside an empty array; say you recurse into empty array of int32, * the signature is "i" but the current type will always be * #DBUS_TYPE_INVALID since there are no elements to be currently * pointing to. * * @param reader the reader * @param str_p place to return the string with the type in it * @param start_p place to return start of the type * @param len_p place to return the length of the type */ void _dbus_type_reader_get_signature (const DBusTypeReader *reader, const DBusString **str_p, int *start_p, int *len_p) { *str_p = reader->type_str; *start_p = reader->type_pos; *len_p = find_len_of_complete_type (reader->type_str, reader->type_pos); } typedef struct { DBusString replacement; int padding; } ReplacementBlock; static dbus_bool_t replacement_block_init (ReplacementBlock *block, DBusTypeReader *reader) { if (!_dbus_string_init (&block->replacement)) return FALSE; /* % 8 is the padding to have the same align properties in * our replacement string as we do at the position being replaced */ block->padding = reader->value_pos % 8; if (!_dbus_string_lengthen (&block->replacement, block->padding)) goto oom; return TRUE; oom: _dbus_string_free (&block->replacement); return FALSE; } static dbus_bool_t replacement_block_replace (ReplacementBlock *block, DBusTypeReader *reader, const DBusTypeReader *realign_root) { DBusTypeWriter writer; DBusTypeReader realign_reader; DBusList *fixups; int orig_len; _dbus_assert (realign_root != NULL); orig_len = _dbus_string_get_length (&block->replacement); realign_reader = *realign_root; #if RECURSIVE_MARSHAL_WRITE_TRACE _dbus_verbose ("INITIALIZING replacement block writer %p at value_pos %d\n", &writer, _dbus_string_get_length (&block->replacement)); #endif _dbus_type_writer_init_values_only (&writer, realign_reader.byte_order, realign_reader.type_str, realign_reader.type_pos, &block->replacement, _dbus_string_get_length (&block->replacement)); _dbus_assert (realign_reader.value_pos <= reader->value_pos); #if RECURSIVE_MARSHAL_WRITE_TRACE _dbus_verbose ("COPYING from reader at value_pos %d to writer %p starting after value_pos %d\n", realign_reader.value_pos, &writer, reader->value_pos); #endif fixups = NULL; if (!_dbus_type_writer_write_reader_partial (&writer, &realign_reader, reader, block->padding, _dbus_string_get_length (&block->replacement) - block->padding, &fixups)) goto oom; #if RECURSIVE_MARSHAL_WRITE_TRACE _dbus_verbose ("REPLACEMENT at padding %d len %d\n", block->padding, _dbus_string_get_length (&block->replacement) - block->padding); _dbus_verbose_bytes_of_string (&block->replacement, block->padding, _dbus_string_get_length (&block->replacement) - block->padding); _dbus_verbose ("TO BE REPLACED at value_pos = %d (align pad %d) len %d realign_reader.value_pos %d\n", reader->value_pos, reader->value_pos % 8, realign_reader.value_pos - reader->value_pos, realign_reader.value_pos); _dbus_verbose_bytes_of_string (reader->value_str, reader->value_pos, realign_reader.value_pos - reader->value_pos); #endif /* Move the replacement into position * (realign_reader should now be at the end of the block to be replaced) */ if (!_dbus_string_replace_len (&block->replacement, block->padding, _dbus_string_get_length (&block->replacement) - block->padding, (DBusString*) reader->value_str, reader->value_pos, realign_reader.value_pos - reader->value_pos)) goto oom; /* Process our fixups now that we can't have an OOM error */ apply_and_free_fixups (&fixups, reader); return TRUE; oom: _dbus_string_set_length (&block->replacement, orig_len); free_fixups (&fixups); return FALSE; } static void replacement_block_free (ReplacementBlock *block) { _dbus_string_free (&block->replacement); } /* In the variable-length case, we have to fix alignment after we insert. * The strategy is as follows: * * - pad a new string to have the same alignment as the * start of the current basic value * - write the new basic value * - copy from the original reader to the new string, * which will fix the alignment of types following * the new value * - this copy has to start at realign_root, * but not really write anything until it * passes the value being set * - as an optimization, we can stop copying * when the source and dest values are both * on an 8-boundary, since we know all following * padding and alignment will be identical * - copy the new string back to the original * string, replacing the relevant part of the * original string * - now any arrays in the original string that * contained the replaced string may have the * wrong length; so we have to fix that */ static dbus_bool_t reader_set_basic_variable_length (DBusTypeReader *reader, int current_type, const void *value, const DBusTypeReader *realign_root) { dbus_bool_t retval; ReplacementBlock block; DBusTypeWriter writer; _dbus_assert (realign_root != NULL); retval = FALSE; if (!replacement_block_init (&block, reader)) return FALSE; /* Write the new basic value */ #if RECURSIVE_MARSHAL_WRITE_TRACE _dbus_verbose ("INITIALIZING writer %p to write basic value at value_pos %d of replacement string\n", &writer, _dbus_string_get_length (&block.replacement)); #endif _dbus_type_writer_init_values_only (&writer, reader->byte_order, reader->type_str, reader->type_pos, &block.replacement, _dbus_string_get_length (&block.replacement)); #if RECURSIVE_MARSHAL_WRITE_TRACE _dbus_verbose ("WRITING basic value to writer %p (replacement string)\n", &writer); #endif if (!_dbus_type_writer_write_basic (&writer, current_type, value)) goto out; if (!replacement_block_replace (&block, reader, realign_root)) goto out; retval = TRUE; out: replacement_block_free (&block); return retval; } static void reader_set_basic_fixed_length (DBusTypeReader *reader, int current_type, const void *value) { _dbus_marshal_set_basic ((DBusString*) reader->value_str, reader->value_pos, current_type, value, reader->byte_order, NULL, NULL); } /** * Sets a new value for the basic type value pointed to by the reader, * leaving the reader valid to continue reading. Any other readers * will be invalidated if you set a variable-length type such as a * string. * * The provided realign_root is the reader to start from when * realigning the data that follows the newly-set value. The reader * parameter must point to a value below the realign_root parameter. * If the type being set is fixed-length, then realign_root may be * #NULL. Only values reachable from realign_root will be realigned, * so if your string contains other values you will need to deal with * those somehow yourself. It is OK if realign_root is the same * reader as the reader parameter, though if you aren't setting the * root it may not be such a good idea. * * @todo DBusTypeReader currently takes "const" versions of the type * and value strings, and this function modifies those strings by * casting away the const, which is of course bad if we want to get * picky. (To be truly clean you'd have an object which contained the * type and value strings and set_basic would be a method on that * object... this would also make DBusTypeReader the same thing as * DBusTypeMark. But since DBusMessage is effectively that object for * D-BUS it doesn't seem worth creating some random object.) * * @todo optimize this by only rewriting until the old and new values * are at the same alignment. Frequently this should result in only * replacing the value that's immediately at hand. * * @param reader reader indicating where to set a new value * @param value address of the value to set * @param realign_root realign from here * @returns #FALSE if not enough memory */ dbus_bool_t _dbus_type_reader_set_basic (DBusTypeReader *reader, const void *value, const DBusTypeReader *realign_root) { int current_type; _dbus_assert (!reader->klass->types_only); _dbus_assert (reader->value_str == realign_root->value_str); _dbus_assert (reader->value_pos >= realign_root->value_pos); current_type = _dbus_type_reader_get_current_type (reader); #if RECURSIVE_MARSHAL_WRITE_TRACE _dbus_verbose (" SET BASIC type reader %p type_pos = %d value_pos = %d remaining sig '%s' realign_root = %p with value_pos %d current_type = %s\n", reader, reader->type_pos, reader->value_pos, _dbus_string_get_const_data_len (reader->type_str, reader->type_pos, 0), realign_root, realign_root ? realign_root->value_pos : -1, _dbus_type_to_string (current_type)); _dbus_verbose_bytes_of_string (realign_root->value_str, realign_root->value_pos, _dbus_string_get_length (realign_root->value_str) - realign_root->value_pos); #endif _dbus_assert (dbus_type_is_basic (current_type)); if (dbus_type_is_fixed (current_type)) { reader_set_basic_fixed_length (reader, current_type, value); return TRUE; } else { _dbus_assert (realign_root != NULL); return reader_set_basic_variable_length (reader, current_type, value, realign_root); } } /** * Recursively deletes any value pointed to by the reader, leaving the * reader valid to continue reading. Any other readers will be * invalidated. * * The provided realign_root is the reader to start from when * realigning the data that follows the newly-set value. * See _dbus_type_reader_set_basic() for more details on the * realign_root paramter. * * @todo for now this does not delete the typecodes associated with * the value, so this function should only be used for array elements. * * @param reader reader indicating where to delete a value * @param realign_root realign from here * @returns #FALSE if not enough memory */ dbus_bool_t _dbus_type_reader_delete (DBusTypeReader *reader, const DBusTypeReader *realign_root) { dbus_bool_t retval; ReplacementBlock block; _dbus_assert (realign_root != NULL); _dbus_assert (reader->klass == &array_reader_class); retval = FALSE; if (!replacement_block_init (&block, reader)) return FALSE; if (!replacement_block_replace (&block, reader, realign_root)) goto out; retval = TRUE; out: replacement_block_free (&block); return retval; } /** * Compares two readers, which must be iterating over the same value data. * Returns #TRUE if the first parameter is further along than the second parameter. * * @param lhs left-hand-side (first) parameter * @param rhs left-hand-side (first) parameter * @returns whether lhs is greater than rhs */ dbus_bool_t _dbus_type_reader_greater_than (const DBusTypeReader *lhs, const DBusTypeReader *rhs) { _dbus_assert (lhs->value_str == rhs->value_str); return lhs->value_pos > rhs->value_pos; } /* * * * DBusTypeWriter * * * */ /** * Initialize a write iterator, which is used to write out values in * serialized D-BUS format. * * The type_pos passed in is expected to be inside an already-valid, * though potentially empty, type signature. This means that the byte * after type_pos must be either #DBUS_TYPE_INVALID (aka nul) or some * other valid type. #DBusTypeWriter won't enforce that the signature * is already valid (you can append the nul byte at the end if you * like), but just be aware that you need the nul byte eventually and * #DBusTypeWriter isn't going to write it for you. * * @param writer the writer to init * @param byte_order the byte order to marshal into * @param type_str the string to write typecodes into * @param type_pos where to insert typecodes * @param value_str the string to write values into * @param value_pos where to insert values * */ void _dbus_type_writer_init (DBusTypeWriter *writer, int byte_order, DBusString *type_str, int type_pos, DBusString *value_str, int value_pos) { writer->byte_order = byte_order; writer->type_str = type_str; writer->type_pos = type_pos; writer->value_str = value_str; writer->value_pos = value_pos; writer->container_type = DBUS_TYPE_INVALID; writer->type_pos_is_expectation = FALSE; writer->enabled = TRUE; #if RECURSIVE_MARSHAL_WRITE_TRACE _dbus_verbose ("writer %p init remaining sig '%s'\n", writer, writer->type_str ? _dbus_string_get_const_data_len (writer->type_str, writer->type_pos, 0) : "unknown"); #endif } /** * Initialize a write iterator, with the signature to be provided * later. * * @param writer the writer to init * @param byte_order the byte order to marshal into * @param value_str the string to write values into * @param value_pos where to insert values * */ void _dbus_type_writer_init_types_delayed (DBusTypeWriter *writer, int byte_order, DBusString *value_str, int value_pos) { _dbus_type_writer_init (writer, byte_order, NULL, 0, value_str, value_pos); } /** * Adds type string to the writer, if it had none. * * @param writer the writer to init * @param type_str type string to add * @param type_pos type position * */ void _dbus_type_writer_add_types (DBusTypeWriter *writer, DBusString *type_str, int type_pos) { if (writer->type_str == NULL) /* keeps us from using this as setter */ { writer->type_str = type_str; writer->type_pos = type_pos; } } /** * Removes type string from the writer. * * @param writer the writer to remove from */ void _dbus_type_writer_remove_types (DBusTypeWriter *writer) { writer->type_str = NULL; writer->type_pos = -1; } /** * Like _dbus_type_writer_init(), except the type string * passed in should correspond to an existing signature that * matches what you're going to write out. The writer will * check what you write vs. this existing signature. * * @param writer the writer to init * @param byte_order the byte order to marshal into * @param type_str the string with signature * @param type_pos start of signature * @param value_str the string to write values into * @param value_pos where to insert values * */ void _dbus_type_writer_init_values_only (DBusTypeWriter *writer, int byte_order, const DBusString *type_str, int type_pos, DBusString *value_str, int value_pos) { _dbus_type_writer_init (writer, byte_order, (DBusString*)type_str, type_pos, value_str, value_pos); writer->type_pos_is_expectation = TRUE; } static dbus_bool_t _dbus_type_writer_write_basic_no_typecode (DBusTypeWriter *writer, int type, const void *value) { if (writer->enabled) return _dbus_marshal_write_basic (writer->value_str, writer->value_pos, type, value, writer->byte_order, &writer->value_pos); else return TRUE; } /* If our parent is an array, things are a little bit complicated. * * The parent must have a complete element type, such as * "i" or "aai" or "(ii)" or "a(ii)". There can't be * unclosed parens, or an "a" with no following type. * * To recurse, the only allowed operation is to recurse into the * first type in the element type. So for "i" you can't recurse, for * "ai" you can recurse into the array, for "(ii)" you can recurse * into the struct. * * If you recurse into the array for "ai", then you must specify * "i" for the element type of the array you recurse into. * * While inside an array at any level, we need to avoid writing to * type_str, since the type only appears once for the whole array, * it does not appear for each array element. * * While inside an array type_pos points to the expected next * typecode, rather than the next place we could write a typecode. */ static void writer_recurse_init_and_check (DBusTypeWriter *writer, int container_type, DBusTypeWriter *sub) { _dbus_type_writer_init (sub, writer->byte_order, writer->type_str, writer->type_pos, writer->value_str, writer->value_pos); sub->container_type = container_type; if (writer->type_pos_is_expectation || (sub->container_type == DBUS_TYPE_ARRAY || sub->container_type == DBUS_TYPE_VARIANT)) sub->type_pos_is_expectation = TRUE; else sub->type_pos_is_expectation = FALSE; sub->enabled = writer->enabled; #ifndef DBUS_DISABLE_CHECKS if (writer->type_pos_is_expectation && writer->type_str) { int expected; expected = _dbus_first_type_in_signature (writer->type_str, writer->type_pos); if (expected != sub->container_type) { _dbus_warn ("Writing an element of type %s, but the expected type here is %s\n", _dbus_type_to_string (sub->container_type), _dbus_type_to_string (expected)); _dbus_assert_not_reached ("bad array element or variant content written"); } } #endif /* DBUS_DISABLE_CHECKS */ #if RECURSIVE_MARSHAL_WRITE_TRACE _dbus_verbose (" type writer %p recurse parent %s type_pos = %d value_pos = %d is_expectation = %d remaining sig '%s' enabled = %d\n", writer, _dbus_type_to_string (writer->container_type), writer->type_pos, writer->value_pos, writer->type_pos_is_expectation, writer->type_str ? _dbus_string_get_const_data_len (writer->type_str, writer->type_pos, 0) : "unknown", writer->enabled); _dbus_verbose (" type writer %p recurse sub %s type_pos = %d value_pos = %d is_expectation = %d enabled = %d\n", sub, _dbus_type_to_string (sub->container_type), sub->type_pos, sub->value_pos, sub->type_pos_is_expectation, sub->enabled); #endif } static dbus_bool_t write_or_verify_typecode (DBusTypeWriter *writer, int typecode) { /* A subwriter inside an array or variant will have type_pos * pointing to the expected typecode; a writer not inside an array * or variant has type_pos pointing to the next place to insert a * typecode. */ #if RECURSIVE_MARSHAL_WRITE_TRACE _dbus_verbose (" type writer %p write_or_verify start type_pos = %d remaining sig '%s' enabled = %d\n", writer, writer->type_pos, writer->type_str ? _dbus_string_get_const_data_len (writer->type_str, writer->type_pos, 0) : "unknown", writer->enabled); #endif if (writer->type_str == NULL) return TRUE; if (writer->type_pos_is_expectation) { #ifndef DBUS_DISABLE_CHECKS { int expected; expected = _dbus_string_get_byte (writer->type_str, writer->type_pos); if (expected != typecode) { _dbus_warn ("Array or variant type requires that type %s be written, but %s was written\n", _dbus_type_to_string (expected), _dbus_type_to_string (typecode)); _dbus_assert_not_reached ("bad type inserted somewhere inside an array or variant"); } } #endif /* DBUS_DISABLE_CHECKS */ /* if immediately inside an array we'd always be appending an element, * so the expected type doesn't change; if inside a struct or something * below an array, we need to move through said struct or something. */ if (writer->container_type != DBUS_TYPE_ARRAY) writer->type_pos += 1; } else { if (!_dbus_string_insert_byte (writer->type_str, writer->type_pos, typecode)) return FALSE; writer->type_pos += 1; } #if RECURSIVE_MARSHAL_WRITE_TRACE _dbus_verbose (" type writer %p write_or_verify end type_pos = %d remaining sig '%s'\n", writer, writer->type_pos, _dbus_string_get_const_data_len (writer->type_str, writer->type_pos, 0)); #endif return TRUE; } static dbus_bool_t writer_recurse_struct_or_dict_entry (DBusTypeWriter *writer, int begin_char, const DBusString *contained_type, int contained_type_start, int contained_type_len, DBusTypeWriter *sub) { /* FIXME right now contained_type is ignored; we could probably * almost trivially fix the code so if it's present we * write it out and then set type_pos_is_expectation */ /* Ensure that we'll be able to add alignment padding and the typecode */ if (writer->enabled) { if (!_dbus_string_alloc_space (sub->value_str, 8)) return FALSE; } if (!write_or_verify_typecode (sub, begin_char)) _dbus_assert_not_reached ("failed to insert struct typecode after prealloc"); if (writer->enabled) { if (!_dbus_string_insert_bytes (sub->value_str, sub->value_pos, _DBUS_ALIGN_VALUE (sub->value_pos, 8) - sub->value_pos, '\0')) _dbus_assert_not_reached ("should not have failed to insert alignment padding for struct"); sub->value_pos = _DBUS_ALIGN_VALUE (sub->value_pos, 8); } return TRUE; } static dbus_bool_t writer_recurse_array (DBusTypeWriter *writer, const DBusString *contained_type, int contained_type_start, int contained_type_len, DBusTypeWriter *sub, dbus_bool_t is_array_append) { dbus_uint32_t value = 0; int alignment; int aligned; #ifndef DBUS_DISABLE_CHECKS if (writer->container_type == DBUS_TYPE_ARRAY && writer->type_str) { if (!_dbus_string_equal_substring (contained_type, contained_type_start, contained_type_len, writer->type_str, writer->u.array.element_type_pos + 1)) { _dbus_warn ("Writing an array of '%s' but this is incompatible with the expected type of elements in the parent array\n", _dbus_string_get_const_data_len (contained_type, contained_type_start, contained_type_len)); _dbus_assert_not_reached ("incompatible type for child array"); } } #endif /* DBUS_DISABLE_CHECKS */ if (writer->enabled && !is_array_append) { /* 3 pad + 4 bytes for the array length, and 4 bytes possible padding * before array values */ if (!_dbus_string_alloc_space (sub->value_str, 3 + 4 + 4)) return FALSE; } if (writer->type_str != NULL) { sub->type_pos += 1; /* move to point to the element type, since type_pos * should be the expected type for further writes */ sub->u.array.element_type_pos = sub->type_pos; } if (!writer->type_pos_is_expectation) { /* sub is a toplevel/outermost array so we need to write the type data */ /* alloc space for array typecode, element signature */ if (!_dbus_string_alloc_space (writer->type_str, 1 + contained_type_len)) return FALSE; if (!_dbus_string_insert_byte (writer->type_str, writer->type_pos, DBUS_TYPE_ARRAY)) _dbus_assert_not_reached ("failed to insert array typecode after prealloc"); if (!_dbus_string_copy_len (contained_type, contained_type_start, contained_type_len, sub->type_str, sub->u.array.element_type_pos)) _dbus_assert_not_reached ("should not have failed to insert array element typecodes"); } if (writer->type_str != NULL) { /* If the parent is an array, we hold type_pos pointing at the array element type; * otherwise advance it to reflect the array value we just recursed into */ if (writer->container_type != DBUS_TYPE_ARRAY) writer->type_pos += 1 + contained_type_len; else _dbus_assert (writer->type_pos_is_expectation); /* because it's an array */ } if (writer->enabled) { /* Write (or jump over, if is_array_append) the length */ sub->u.array.len_pos = _DBUS_ALIGN_VALUE (sub->value_pos, 4); if (is_array_append) { sub->value_pos += 4; } else { if (!_dbus_type_writer_write_basic_no_typecode (sub, DBUS_TYPE_UINT32, &value)) _dbus_assert_not_reached ("should not have failed to insert array len"); } _dbus_assert (sub->u.array.len_pos == sub->value_pos - 4); /* Write alignment padding for array elements * Note that we write the padding *even for empty arrays* * to avoid wonky special cases */ alignment = element_type_get_alignment (contained_type, contained_type_start); aligned = _DBUS_ALIGN_VALUE (sub->value_pos, alignment); if (aligned != sub->value_pos) { if (!is_array_append) { if (!_dbus_string_insert_bytes (sub->value_str, sub->value_pos, aligned - sub->value_pos, '\0')) _dbus_assert_not_reached ("should not have failed to insert alignment padding"); } sub->value_pos = aligned; } sub->u.array.start_pos = sub->value_pos; if (is_array_append) { dbus_uint32_t len; _dbus_assert (_DBUS_ALIGN_VALUE (sub->u.array.len_pos, 4) == (unsigned) sub->u.array.len_pos); len = _dbus_unpack_uint32 (sub->byte_order, _dbus_string_get_const_data_len (sub->value_str, sub->u.array.len_pos, 4)); sub->value_pos += len; } } else { /* not enabled, so we won't write the len_pos; set it to -1 to so indicate */ sub->u.array.len_pos = -1; sub->u.array.start_pos = sub->value_pos; } _dbus_assert (sub->u.array.len_pos < sub->u.array.start_pos); _dbus_assert (is_array_append || sub->u.array.start_pos == sub->value_pos); #if RECURSIVE_MARSHAL_WRITE_TRACE _dbus_verbose (" type writer %p recurse array done remaining sig '%s' array start_pos = %d len_pos = %d value_pos = %d\n", sub, sub->type_str ? _dbus_string_get_const_data_len (sub->type_str, sub->type_pos, 0) : "unknown", sub->u.array.start_pos, sub->u.array.len_pos, sub->value_pos); #endif return TRUE; } /* Variant value will normally have: * 1 byte signature length not including nul * signature typecodes (nul terminated) * padding to alignment of contained type * body according to signature * * The signature string can only have a single type * in it but that type may be complex/recursive. * * So a typical variant type with the integer 3 will have these * octets: * 0x1 'i' '\0' [1 byte padding to alignment boundary] 0x0 0x0 0x0 0x3 * * The main world of hurt for writing out a variant is that the type * string is the same string as the value string. Which means * inserting to the type string will move the value_pos; and it means * that inserting to the type string could break type alignment. */ static dbus_bool_t writer_recurse_variant (DBusTypeWriter *writer, const DBusString *contained_type, int contained_type_start, int contained_type_len, DBusTypeWriter *sub) { int contained_alignment; if (writer->enabled) { /* Allocate space for the worst case, which is 1 byte sig * length, nul byte at end of sig, and 7 bytes padding to * 8-boundary. */ if (!_dbus_string_alloc_space (sub->value_str, contained_type_len + 9)) return FALSE; } /* write VARIANT typecode to the parent's type string */ if (!write_or_verify_typecode (writer, DBUS_TYPE_VARIANT)) return FALSE; /* If not enabled, mark that we have no type_str anymore ... */ if (!writer->enabled) { sub->type_str = NULL; sub->type_pos = -1; return TRUE; } /* If we're enabled then continue ... */ if (!_dbus_string_insert_byte (sub->value_str, sub->value_pos, contained_type_len)) _dbus_assert_not_reached ("should not have failed to insert variant type sig len"); sub->value_pos += 1; /* Here we switch over to the expected type sig we're about to write */ sub->type_str = sub->value_str; sub->type_pos = sub->value_pos; if (!_dbus_string_copy_len (contained_type, contained_type_start, contained_type_len, sub->value_str, sub->value_pos)) _dbus_assert_not_reached ("should not have failed to insert variant type sig"); sub->value_pos += contained_type_len; if (!_dbus_string_insert_byte (sub->value_str, sub->value_pos, DBUS_TYPE_INVALID)) _dbus_assert_not_reached ("should not have failed to insert variant type nul termination"); sub->value_pos += 1; contained_alignment = _dbus_type_get_alignment (_dbus_first_type_in_signature (contained_type, contained_type_start)); if (!_dbus_string_insert_bytes (sub->value_str, sub->value_pos, _DBUS_ALIGN_VALUE (sub->value_pos, contained_alignment) - sub->value_pos, '\0')) _dbus_assert_not_reached ("should not have failed to insert alignment padding for variant body"); sub->value_pos = _DBUS_ALIGN_VALUE (sub->value_pos, contained_alignment); return TRUE; } static dbus_bool_t _dbus_type_writer_recurse_contained_len (DBusTypeWriter *writer, int container_type, const DBusString *contained_type, int contained_type_start, int contained_type_len, DBusTypeWriter *sub, dbus_bool_t is_array_append) { writer_recurse_init_and_check (writer, container_type, sub); switch (container_type) { case DBUS_TYPE_STRUCT: return writer_recurse_struct_or_dict_entry (writer, DBUS_STRUCT_BEGIN_CHAR, contained_type, contained_type_start, contained_type_len, sub); break; case DBUS_TYPE_DICT_ENTRY: return writer_recurse_struct_or_dict_entry (writer, DBUS_DICT_ENTRY_BEGIN_CHAR, contained_type, contained_type_start, contained_type_len, sub); break; case DBUS_TYPE_ARRAY: return writer_recurse_array (writer, contained_type, contained_type_start, contained_type_len, sub, is_array_append); break; case DBUS_TYPE_VARIANT: return writer_recurse_variant (writer, contained_type, contained_type_start, contained_type_len, sub); break; default: _dbus_assert_not_reached ("tried to recurse into type that doesn't support that"); return FALSE; break; } } /** * Opens a new container and writes out the initial information for that container. * * @param writer the writer * @param container_type the type of the container to open * @param contained_type the array element type or variant content type * @param contained_type_start position to look for the type * @param sub the new sub-writer to write container contents * @returns #FALSE if no memory */ dbus_bool_t _dbus_type_writer_recurse (DBusTypeWriter *writer, int container_type, const DBusString *contained_type, int contained_type_start, DBusTypeWriter *sub) { int contained_type_len; if (contained_type) contained_type_len = find_len_of_complete_type (contained_type, contained_type_start); else contained_type_len = 0; return _dbus_type_writer_recurse_contained_len (writer, container_type, contained_type, contained_type_start, contained_type_len, sub, FALSE); } /** * Append to an existing array. Essentially, the writer will read an * existing length at the write location; jump over that length; and * write new fields. On unrecurse(), the existing length will be * updated. * * @param writer the writer * @param contained_type element type * @param contained_type_start position of element type * @param sub the subwriter to init * @returns #FALSE if no memory */ dbus_bool_t _dbus_type_writer_append_array (DBusTypeWriter *writer, const DBusString *contained_type, int contained_type_start, DBusTypeWriter *sub) { int contained_type_len; if (contained_type) contained_type_len = find_len_of_complete_type (contained_type, contained_type_start); else contained_type_len = 0; return _dbus_type_writer_recurse_contained_len (writer, DBUS_TYPE_ARRAY, contained_type, contained_type_start, contained_type_len, sub, TRUE); } static int writer_get_array_len (DBusTypeWriter *writer) { _dbus_assert (writer->container_type == DBUS_TYPE_ARRAY); return writer->value_pos - writer->u.array.start_pos; } /** * Closes a container created by _dbus_type_writer_recurse() * and writes any additional information to the values block. * * @param writer the writer * @param sub the sub-writer created by _dbus_type_writer_recurse() * @returns #FALSE if no memory */ dbus_bool_t _dbus_type_writer_unrecurse (DBusTypeWriter *writer, DBusTypeWriter *sub) { /* type_pos_is_expectation never gets unset once set, or we'd get all hosed */ _dbus_assert (!writer->type_pos_is_expectation || (writer->type_pos_is_expectation && sub->type_pos_is_expectation)); #if RECURSIVE_MARSHAL_WRITE_TRACE _dbus_verbose (" type writer %p unrecurse type_pos = %d value_pos = %d is_expectation = %d container_type = %s\n", writer, writer->type_pos, writer->value_pos, writer->type_pos_is_expectation, _dbus_type_to_string (writer->container_type)); _dbus_verbose (" type writer %p unrecurse sub type_pos = %d value_pos = %d is_expectation = %d container_type = %s\n", sub, sub->type_pos, sub->value_pos, sub->type_pos_is_expectation, _dbus_type_to_string (sub->container_type)); #endif if (sub->container_type == DBUS_TYPE_STRUCT) { if (!write_or_verify_typecode (sub, DBUS_STRUCT_END_CHAR)) return FALSE; } else if (sub->container_type == DBUS_TYPE_DICT_ENTRY) { if (!write_or_verify_typecode (sub, DBUS_DICT_ENTRY_END_CHAR)) return FALSE; } else if (sub->container_type == DBUS_TYPE_ARRAY) { if (sub->u.array.len_pos >= 0) /* len_pos == -1 if we weren't enabled when we passed it */ { dbus_uint32_t len; /* Set the array length */ len = writer_get_array_len (sub); _dbus_marshal_set_uint32 (sub->value_str, sub->u.array.len_pos, len, sub->byte_order); #if RECURSIVE_MARSHAL_WRITE_TRACE _dbus_verbose (" filled in sub array len to %u at len_pos %d\n", len, sub->u.array.len_pos); #endif } #if RECURSIVE_MARSHAL_WRITE_TRACE else { _dbus_verbose (" not filling in sub array len because we were disabled when we passed the len\n"); } #endif } /* Now get type_pos right for the parent writer. Here are the cases: * * Cases !writer->type_pos_is_expectation: * (in these cases we want to update to the new insertion point) * * - if we recursed into a STRUCT then we didn't know in advance * what the types in the struct would be; so we have to fill in * that information now. * writer->type_pos = sub->type_pos * * - if we recursed into anything else, we knew the full array * type, or knew the single typecode marking VARIANT, so * writer->type_pos is already correct. * writer->type_pos should remain as-is * * - note that the parent is never an ARRAY or VARIANT, if it were * then type_pos_is_expectation would be TRUE. The parent * is thus known to be a toplevel or STRUCT. * * Cases where writer->type_pos_is_expectation: * (in these cases we want to update to next expected type to write) * * - we recursed from STRUCT into STRUCT and we didn't increment * type_pos in the parent just to stay consistent with the * !writer->type_pos_is_expectation case (though we could * special-case this in recurse_struct instead if we wanted) * writer->type_pos = sub->type_pos * * - we recursed from STRUCT into ARRAY or VARIANT and type_pos * for parent should have been incremented already * writer->type_pos should remain as-is * * - we recursed from ARRAY into a sub-element, so type_pos in the * parent is the element type and should remain the element type * for the benefit of the next child element * writer->type_pos should remain as-is * * - we recursed from VARIANT into its value, so type_pos in the * parent makes no difference since there's only one value * and we just finished writing it and won't use type_pos again * writer->type_pos should remain as-is * * * For all these, DICT_ENTRY is the same as STRUCT */ if (writer->type_str != NULL) { if ((sub->container_type == DBUS_TYPE_STRUCT || sub->container_type == DBUS_TYPE_DICT_ENTRY) && (writer->container_type == DBUS_TYPE_STRUCT || writer->container_type == DBUS_TYPE_DICT_ENTRY || writer->container_type == DBUS_TYPE_INVALID)) { /* Advance the parent to the next struct field */ writer->type_pos = sub->type_pos; } } writer->value_pos = sub->value_pos; #if RECURSIVE_MARSHAL_WRITE_TRACE _dbus_verbose (" type writer %p unrecursed type_pos = %d value_pos = %d remaining sig '%s'\n", writer, writer->type_pos, writer->value_pos, writer->type_str ? _dbus_string_get_const_data_len (writer->type_str, writer->type_pos, 0) : "unknown"); #endif return TRUE; } /** * Writes out a basic type. * * @param writer the writer * @param type the type to write * @param value the address of the value to write * @returns #FALSE if no memory */ dbus_bool_t _dbus_type_writer_write_basic (DBusTypeWriter *writer, int type, const void *value) { dbus_bool_t retval; /* First ensure that our type realloc will succeed */ if (!writer->type_pos_is_expectation && writer->type_str != NULL) { if (!_dbus_string_alloc_space (writer->type_str, 1)) return FALSE; } retval = FALSE; if (!_dbus_type_writer_write_basic_no_typecode (writer, type, value)) goto out; if (!write_or_verify_typecode (writer, type)) _dbus_assert_not_reached ("failed to write typecode after prealloc"); retval = TRUE; out: #if RECURSIVE_MARSHAL_WRITE_TRACE _dbus_verbose (" type writer %p basic type_pos = %d value_pos = %d is_expectation = %d enabled = %d\n", writer, writer->type_pos, writer->value_pos, writer->type_pos_is_expectation, writer->enabled); #endif return retval; } /** * Writes a block of fixed-length basic values, i.e. those that are * both dbus_type_is_fixed() and _dbus_type_is_basic(). The block * must be written inside an array. * * The value parameter should be the address of said array of values, * so e.g. if it's an array of double, pass in "const double**" * * @param writer the writer * @param element_type type of stuff in the array * @param value address of the array * @param n_elements number of elements in the array * @returns #FALSE if no memory */ dbus_bool_t _dbus_type_writer_write_fixed_multi (DBusTypeWriter *writer, int element_type, const void *value, int n_elements) { _dbus_assert (writer->container_type == DBUS_TYPE_ARRAY); _dbus_assert (dbus_type_is_fixed (element_type)); _dbus_assert (writer->type_pos_is_expectation); _dbus_assert (n_elements >= 0); #if RECURSIVE_MARSHAL_WRITE_TRACE _dbus_verbose (" type writer %p entering fixed multi type_pos = %d value_pos = %d n_elements %d\n", writer, writer->type_pos, writer->value_pos, n_elements); #endif if (!write_or_verify_typecode (writer, element_type)) _dbus_assert_not_reached ("OOM should not happen if only verifying typecode"); if (writer->enabled) { if (!_dbus_marshal_write_fixed_multi (writer->value_str, writer->value_pos, element_type, value, n_elements, writer->byte_order, &writer->value_pos)) return FALSE; } #if RECURSIVE_MARSHAL_WRITE_TRACE _dbus_verbose (" type writer %p fixed multi written new type_pos = %d new value_pos = %d n_elements %d\n", writer, writer->type_pos, writer->value_pos, n_elements); #endif return TRUE; } static void enable_if_after (DBusTypeWriter *writer, DBusTypeReader *reader, const DBusTypeReader *start_after) { if (start_after) { if (!writer->enabled && _dbus_type_reader_greater_than (reader, start_after)) { _dbus_type_writer_set_enabled (writer, TRUE); #if RECURSIVE_MARSHAL_WRITE_TRACE _dbus_verbose ("ENABLING writer %p at %d because reader at value_pos %d is after reader at value_pos %d\n", writer, writer->value_pos, reader->value_pos, start_after->value_pos); #endif } _dbus_assert ((!writer->enabled && !_dbus_type_reader_greater_than (reader, start_after)) || (writer->enabled && _dbus_type_reader_greater_than (reader, start_after))); } } static dbus_bool_t append_fixup (DBusList **fixups, const DBusArrayLenFixup *fixup) { DBusArrayLenFixup *f; f = dbus_new (DBusArrayLenFixup, 1); if (f == NULL) return FALSE; *f = *fixup; if (!_dbus_list_append (fixups, f)) { dbus_free (f); return FALSE; } _dbus_assert (f->len_pos_in_reader == fixup->len_pos_in_reader); _dbus_assert (f->new_len == fixup->new_len); return TRUE; } /* This loop is trivial if you ignore all the start_after nonsense, * so if you're trying to figure it out, start by ignoring that */ static dbus_bool_t writer_write_reader_helper (DBusTypeWriter *writer, DBusTypeReader *reader, const DBusTypeReader *start_after, int start_after_new_pos, int start_after_new_len, DBusList **fixups, dbus_bool_t inside_start_after) { int current_type; while ((current_type = _dbus_type_reader_get_current_type (reader)) != DBUS_TYPE_INVALID) { if (dbus_type_is_container (current_type)) { DBusTypeReader subreader; DBusTypeWriter subwriter; const DBusString *sig_str; int sig_start; int sig_len; dbus_bool_t enabled_at_recurse; dbus_bool_t past_start_after; int reader_array_len_pos; int reader_array_start_pos; dbus_bool_t this_is_start_after; /* type_pos is checked since e.g. in a struct the struct * and its first field have the same value_pos. * type_str will differ in reader/start_after for variants * where type_str is inside the value_str */ if (!inside_start_after && start_after && reader->value_pos == start_after->value_pos && reader->type_str == start_after->type_str && reader->type_pos == start_after->type_pos) this_is_start_after = TRUE; else this_is_start_after = FALSE; _dbus_type_reader_recurse (reader, &subreader); if (current_type == DBUS_TYPE_ARRAY) { reader_array_len_pos = ARRAY_READER_LEN_POS (&subreader); reader_array_start_pos = subreader.u.array.start_pos; } else { /* quiet gcc */ reader_array_len_pos = -1; reader_array_start_pos = -1; } _dbus_type_reader_get_signature (&subreader, &sig_str, &sig_start, &sig_len); #if RECURSIVE_MARSHAL_WRITE_TRACE _dbus_verbose ("about to recurse into %s reader at %d subreader at %d writer at %d start_after reader at %d write target len %d inside_start_after = %d this_is_start_after = %d\n", _dbus_type_to_string (current_type), reader->value_pos, subreader.value_pos, writer->value_pos, start_after ? start_after->value_pos : -1, _dbus_string_get_length (writer->value_str), inside_start_after, this_is_start_after); #endif if (!inside_start_after && !this_is_start_after) enable_if_after (writer, &subreader, start_after); enabled_at_recurse = writer->enabled; if (!_dbus_type_writer_recurse_contained_len (writer, current_type, sig_str, sig_start, sig_len, &subwriter, FALSE)) goto oom; #if RECURSIVE_MARSHAL_WRITE_TRACE _dbus_verbose ("recursed into subwriter at %d write target len %d\n", subwriter.value_pos, _dbus_string_get_length (subwriter.value_str)); #endif if (!writer_write_reader_helper (&subwriter, &subreader, start_after, start_after_new_pos, start_after_new_len, fixups, inside_start_after || this_is_start_after)) goto oom; #if RECURSIVE_MARSHAL_WRITE_TRACE _dbus_verbose ("about to unrecurse from %s subreader at %d writer at %d subwriter at %d write target len %d\n", _dbus_type_to_string (current_type), subreader.value_pos, writer->value_pos, subwriter.value_pos, _dbus_string_get_length (writer->value_str)); #endif if (!inside_start_after && !this_is_start_after) enable_if_after (writer, &subreader, start_after); past_start_after = writer->enabled; if (!_dbus_type_writer_unrecurse (writer, &subwriter)) goto oom; /* If we weren't enabled when we recursed, we didn't * write an array len; if we passed start_after * somewhere inside the array, then we need to generate * a fixup. */ if (start_after != NULL && !enabled_at_recurse && past_start_after && current_type == DBUS_TYPE_ARRAY && fixups != NULL) { DBusArrayLenFixup fixup; int bytes_written_after_start_after; int bytes_before_start_after; int old_len; /* this subwriter access is moderately unkosher since we * already unrecursed, but it works as long as unrecurse * doesn't break us on purpose */ bytes_written_after_start_after = writer_get_array_len (&subwriter); bytes_before_start_after = start_after->value_pos - reader_array_start_pos; fixup.len_pos_in_reader = reader_array_len_pos; fixup.new_len = bytes_before_start_after + start_after_new_len + bytes_written_after_start_after; _dbus_assert (_DBUS_ALIGN_VALUE (fixup.len_pos_in_reader, 4) == (unsigned) fixup.len_pos_in_reader); old_len = _dbus_unpack_uint32 (reader->byte_order, _dbus_string_get_const_data_len (reader->value_str, fixup.len_pos_in_reader, 4)); if (old_len != fixup.new_len && !append_fixup (fixups, &fixup)) goto oom; #if RECURSIVE_MARSHAL_WRITE_TRACE _dbus_verbose ("Generated fixup len_pos_in_reader = %d new_len = %d reader_array_start_pos = %d start_after->value_pos = %d bytes_before_start_after = %d start_after_new_len = %d bytes_written_after_start_after = %d\n", fixup.len_pos_in_reader, fixup.new_len, reader_array_start_pos, start_after->value_pos, bytes_before_start_after, start_after_new_len, bytes_written_after_start_after); #endif } } else { DBusBasicValue val; _dbus_assert (dbus_type_is_basic (current_type)); #if RECURSIVE_MARSHAL_WRITE_TRACE _dbus_verbose ("Reading basic value %s at %d\n", _dbus_type_to_string (current_type), reader->value_pos); #endif _dbus_type_reader_read_basic (reader, &val); #if RECURSIVE_MARSHAL_WRITE_TRACE _dbus_verbose ("Writing basic value %s at %d write target len %d inside_start_after = %d\n", _dbus_type_to_string (current_type), writer->value_pos, _dbus_string_get_length (writer->value_str), inside_start_after); #endif if (!inside_start_after) enable_if_after (writer, reader, start_after); if (!_dbus_type_writer_write_basic (writer, current_type, &val)) goto oom; #if RECURSIVE_MARSHAL_WRITE_TRACE _dbus_verbose ("Wrote basic value %s, new value_pos %d write target len %d\n", _dbus_type_to_string (current_type), writer->value_pos, _dbus_string_get_length (writer->value_str)); #endif } _dbus_type_reader_next (reader); } return TRUE; oom: if (fixups) apply_and_free_fixups (fixups, NULL); /* NULL for reader to apply to */ return FALSE; } /** * Iterate through all values in the given reader, writing a copy of * each value to the writer. The reader will be moved forward to its * end position. * * If a reader start_after is provided, it should be a reader for the * same data as the reader to be written. Only values occurring after * the value pointed to by start_after will be written to the writer. * * If start_after is provided, then the copy of the reader will be * partial. This means that array lengths will not have been copied. * The assumption is that you wrote a new version of the value at * start_after to the writer. You have to pass in the start position * and length of the new value. (If you are deleting the value * at start_after, pass in 0 for the length.) * * If the fixups parameter is non-#NULL, then any array length that * was read but not written due to start_after will be provided * as a #DBusArrayLenFixup. The fixup contains the position of the * array length in the source data, and the correct array length * assuming you combine the source data before start_after with * the written data at start_after and beyond. * * @param writer the writer to copy to * @param reader the reader to copy from * @param start_after #NULL or a reader showing where to start * @param start_after_new_pos the position of start_after equivalent in the target data * @param start_after_new_len the length of start_after equivalent in the target data * @param fixups list to append #DBusArrayLenFixup if the write was partial * @returns #FALSE if no memory */ dbus_bool_t _dbus_type_writer_write_reader_partial (DBusTypeWriter *writer, DBusTypeReader *reader, const DBusTypeReader *start_after, int start_after_new_pos, int start_after_new_len, DBusList **fixups) { DBusTypeWriter orig; int orig_type_len; int orig_value_len; int new_bytes; int orig_enabled; orig = *writer; orig_type_len = _dbus_string_get_length (writer->type_str); orig_value_len = _dbus_string_get_length (writer->value_str); orig_enabled = writer->enabled; if (start_after) _dbus_type_writer_set_enabled (writer, FALSE); if (!writer_write_reader_helper (writer, reader, start_after, start_after_new_pos, start_after_new_len, fixups, FALSE)) goto oom; _dbus_type_writer_set_enabled (writer, orig_enabled); return TRUE; oom: if (!writer->type_pos_is_expectation) { new_bytes = _dbus_string_get_length (writer->type_str) - orig_type_len; _dbus_string_delete (writer->type_str, orig.type_pos, new_bytes); } new_bytes = _dbus_string_get_length (writer->value_str) - orig_value_len; _dbus_string_delete (writer->value_str, orig.value_pos, new_bytes); *writer = orig; return FALSE; } /** * Iterate through all values in the given reader, writing a copy of * each value to the writer. The reader will be moved forward to its * end position. * * @param writer the writer to copy to * @param reader the reader to copy from * @returns #FALSE if no memory */ dbus_bool_t _dbus_type_writer_write_reader (DBusTypeWriter *writer, DBusTypeReader *reader) { return _dbus_type_writer_write_reader_partial (writer, reader, NULL, 0, 0, NULL); } /** * If disabled, a writer can still be iterated forward and recursed/unrecursed * but won't write any values. Types will still be written unless the * writer is a "values only" writer, because the writer needs access to * a valid signature to be able to iterate. * * @param writer the type writer * @param enabled #TRUE if values should be written */ void _dbus_type_writer_set_enabled (DBusTypeWriter *writer, dbus_bool_t enabled) { writer->enabled = enabled != FALSE; } /** @} */ /* end of DBusMarshal group */ /* tests in dbus-marshal-recursive-util.c */