--- /dev/null
+/* pb_decode.c -- decode a protobuf using minimal resources
+ *
+ * 2011 Petteri Aimonen <jpa@kapsi.fi>
+ */
+
+/* Use the GCC warn_unused_result attribute to check that all return values
+ * are propagated correctly. On other compilers and gcc before 3.4.0 just
+ * ignore the annotation.
+ */
+#if !defined(__GNUC__) || ( __GNUC__ < 3) || (__GNUC__ == 3 && __GNUC_MINOR__ < 4)
+ #define checkreturn
+#else
+ #define checkreturn __attribute__((warn_unused_result))
+#endif
+
+#include "pb.h"
+#include "pb_decode.h"
+#include "pb_common.h"
+
+/**************************************
+ * Declarations internal to this file *
+ **************************************/
+
+typedef bool (*pb_decoder_t)(pb_istream_t *stream, const pb_field_t *field, void *dest) checkreturn;
+
+static bool checkreturn buf_read(pb_istream_t *stream, pb_byte_t *buf, size_t count);
+static bool checkreturn read_raw_value(pb_istream_t *stream, pb_wire_type_t wire_type, pb_byte_t *buf, size_t *size);
+static bool checkreturn decode_static_field(pb_istream_t *stream, pb_wire_type_t wire_type, pb_field_iter_t *iter);
+static bool checkreturn decode_callback_field(pb_istream_t *stream, pb_wire_type_t wire_type, pb_field_iter_t *iter);
+static bool checkreturn decode_field(pb_istream_t *stream, pb_wire_type_t wire_type, pb_field_iter_t *iter);
+static void iter_from_extension(pb_field_iter_t *iter, pb_extension_t *extension);
+static bool checkreturn default_extension_decoder(pb_istream_t *stream, pb_extension_t *extension, uint32_t tag, pb_wire_type_t wire_type);
+static bool checkreturn decode_extension(pb_istream_t *stream, uint32_t tag, pb_wire_type_t wire_type, pb_field_iter_t *iter);
+static bool checkreturn find_extension_field(pb_field_iter_t *iter);
+static void pb_field_set_to_default(pb_field_iter_t *iter);
+static void pb_message_set_to_defaults(const pb_field_t fields[], void *dest_struct);
+static bool checkreturn pb_dec_varint(pb_istream_t *stream, const pb_field_t *field, void *dest);
+static bool checkreturn pb_dec_uvarint(pb_istream_t *stream, const pb_field_t *field, void *dest);
+static bool checkreturn pb_dec_svarint(pb_istream_t *stream, const pb_field_t *field, void *dest);
+static bool checkreturn pb_dec_fixed32(pb_istream_t *stream, const pb_field_t *field, void *dest);
+static bool checkreturn pb_dec_fixed64(pb_istream_t *stream, const pb_field_t *field, void *dest);
+static bool checkreturn pb_dec_bytes(pb_istream_t *stream, const pb_field_t *field, void *dest);
+static bool checkreturn pb_dec_string(pb_istream_t *stream, const pb_field_t *field, void *dest);
+static bool checkreturn pb_dec_submessage(pb_istream_t *stream, const pb_field_t *field, void *dest);
+static bool checkreturn pb_dec_fixed_length_bytes(pb_istream_t *stream, const pb_field_t *field, void *dest);
+static bool checkreturn pb_skip_varint(pb_istream_t *stream);
+static bool checkreturn pb_skip_string(pb_istream_t *stream);
+
+#ifdef PB_ENABLE_MALLOC
+static bool checkreturn allocate_field(pb_istream_t *stream, void *pData, size_t data_size, size_t array_size);
+static bool checkreturn pb_release_union_field(pb_istream_t *stream, pb_field_iter_t *iter);
+static void pb_release_single_field(const pb_field_iter_t *iter);
+#endif
+
+/* --- Function pointers to field decoders ---
+ * Order in the array must match pb_action_t LTYPE numbering.
+ */
+static const pb_decoder_t PB_DECODERS[PB_LTYPES_COUNT] = {
+ &pb_dec_varint,
+ &pb_dec_uvarint,
+ &pb_dec_svarint,
+ &pb_dec_fixed32,
+ &pb_dec_fixed64,
+
+ &pb_dec_bytes,
+ &pb_dec_string,
+ &pb_dec_submessage,
+ NULL, /* extensions */
+ &pb_dec_fixed_length_bytes
+};
+
+/*******************************
+ * pb_istream_t implementation *
+ *******************************/
+
+static bool checkreturn buf_read(pb_istream_t *stream, pb_byte_t *buf, size_t count)
+{
+ size_t i;
+ const pb_byte_t *source = (const pb_byte_t*)stream->state;
+ stream->state = (pb_byte_t*)stream->state + count;
+
+ if (buf != NULL)
+ {
+ for (i = 0; i < count; i++)
+ buf[i] = source[i];
+ }
+
+ return true;
+}
+
+bool checkreturn pb_read(pb_istream_t *stream, pb_byte_t *buf, size_t count)
+{
+#ifndef PB_BUFFER_ONLY
+ if (buf == NULL && stream->callback != buf_read)
+ {
+ /* Skip input bytes */
+ pb_byte_t tmp[16];
+ while (count > 16)
+ {
+ if (!pb_read(stream, tmp, 16))
+ return false;
+
+ count -= 16;
+ }
+
+ return pb_read(stream, tmp, count);
+ }
+#endif
+
+ if (stream->bytes_left < count)
+ PB_RETURN_ERROR(stream, "end-of-stream");
+
+#ifndef PB_BUFFER_ONLY
+ if (!stream->callback(stream, buf, count))
+ PB_RETURN_ERROR(stream, "io error");
+#else
+ if (!buf_read(stream, buf, count))
+ return false;
+#endif
+
+ stream->bytes_left -= count;
+ return true;
+}
+
+/* Read a single byte from input stream. buf may not be NULL.
+ * This is an optimization for the varint decoding. */
+static bool checkreturn pb_readbyte(pb_istream_t *stream, pb_byte_t *buf)
+{
+ if (stream->bytes_left == 0)
+ PB_RETURN_ERROR(stream, "end-of-stream");
+
+#ifndef PB_BUFFER_ONLY
+ if (!stream->callback(stream, buf, 1))
+ PB_RETURN_ERROR(stream, "io error");
+#else
+ *buf = *(const pb_byte_t*)stream->state;
+ stream->state = (pb_byte_t*)stream->state + 1;
+#endif
+
+ stream->bytes_left--;
+
+ return true;
+}
+
+pb_istream_t pb_istream_from_buffer(const pb_byte_t *buf, size_t bufsize)
+{
+ pb_istream_t stream;
+ /* Cast away the const from buf without a compiler error. We are
+ * careful to use it only in a const manner in the callbacks.
+ */
+ union {
+ void *state;
+ const void *c_state;
+ } state;
+#ifdef PB_BUFFER_ONLY
+ stream.callback = NULL;
+#else
+ stream.callback = &buf_read;
+#endif
+ state.c_state = buf;
+ stream.state = state.state;
+ stream.bytes_left = bufsize;
+#ifndef PB_NO_ERRMSG
+ stream.errmsg = NULL;
+#endif
+ return stream;
+}
+
+/********************
+ * Helper functions *
+ ********************/
+
+bool checkreturn pb_decode_varint32(pb_istream_t *stream, uint32_t *dest)
+{
+ pb_byte_t byte;
+ uint32_t result;
+
+ if (!pb_readbyte(stream, &byte))
+ return false;
+
+ if ((byte & 0x80) == 0)
+ {
+ /* Quick case, 1 byte value */
+ result = byte;
+ }
+ else
+ {
+ /* Multibyte case */
+ uint_fast8_t bitpos = 7;
+ result = byte & 0x7F;
+
+ do
+ {
+ if (bitpos >= 32)
+ PB_RETURN_ERROR(stream, "varint overflow");
+
+ if (!pb_readbyte(stream, &byte))
+ return false;
+
+ result |= (uint32_t)(byte & 0x7F) << bitpos;
+ bitpos = (uint_fast8_t)(bitpos + 7);
+ } while (byte & 0x80);
+ }
+
+ *dest = result;
+ return true;
+}
+
+bool checkreturn pb_decode_varint(pb_istream_t *stream, uint64_t *dest)
+{
+ pb_byte_t byte;
+ uint_fast8_t bitpos = 0;
+ uint64_t result = 0;
+
+ do
+ {
+ if (bitpos >= 64)
+ PB_RETURN_ERROR(stream, "varint overflow");
+
+ if (!pb_readbyte(stream, &byte))
+ return false;
+
+ result |= (uint64_t)(byte & 0x7F) << bitpos;
+ bitpos = (uint_fast8_t)(bitpos + 7);
+ } while (byte & 0x80);
+
+ *dest = result;
+ return true;
+}
+
+bool checkreturn pb_skip_varint(pb_istream_t *stream)
+{
+ pb_byte_t byte;
+ do
+ {
+ if (!pb_read(stream, &byte, 1))
+ return false;
+ } while (byte & 0x80);
+ return true;
+}
+
+bool checkreturn pb_skip_string(pb_istream_t *stream)
+{
+ uint32_t length;
+ if (!pb_decode_varint32(stream, &length))
+ return false;
+
+ return pb_read(stream, NULL, length);
+}
+
+bool checkreturn pb_decode_tag(pb_istream_t *stream, pb_wire_type_t *wire_type, uint32_t *tag, bool *eof)
+{
+ uint32_t temp;
+ *eof = false;
+ *wire_type = (pb_wire_type_t) 0;
+ *tag = 0;
+
+ if (!pb_decode_varint32(stream, &temp))
+ {
+ if (stream->bytes_left == 0)
+ *eof = true;
+
+ return false;
+ }
+
+ if (temp == 0)
+ {
+ *eof = true; /* Special feature: allow 0-terminated messages. */
+ return false;
+ }
+
+ *tag = temp >> 3;
+ *wire_type = (pb_wire_type_t)(temp & 7);
+ return true;
+}
+
+bool checkreturn pb_skip_field(pb_istream_t *stream, pb_wire_type_t wire_type)
+{
+ switch (wire_type)
+ {
+ case PB_WT_VARINT: return pb_skip_varint(stream);
+ case PB_WT_64BIT: return pb_read(stream, NULL, 8);
+ case PB_WT_STRING: return pb_skip_string(stream);
+ case PB_WT_32BIT: return pb_read(stream, NULL, 4);
+ default: PB_RETURN_ERROR(stream, "invalid wire_type");
+ }
+}
+
+/* Read a raw value to buffer, for the purpose of passing it to callback as
+ * a substream. Size is maximum size on call, and actual size on return.
+ */
+static bool checkreturn read_raw_value(pb_istream_t *stream, pb_wire_type_t wire_type, pb_byte_t *buf, size_t *size)
+{
+ size_t max_size = *size;
+ switch (wire_type)
+ {
+ case PB_WT_VARINT:
+ *size = 0;
+ do
+ {
+ (*size)++;
+ if (*size > max_size) return false;
+ if (!pb_read(stream, buf, 1)) return false;
+ } while (*buf++ & 0x80);
+ return true;
+
+ case PB_WT_64BIT:
+ *size = 8;
+ return pb_read(stream, buf, 8);
+
+ case PB_WT_32BIT:
+ *size = 4;
+ return pb_read(stream, buf, 4);
+
+ default: PB_RETURN_ERROR(stream, "invalid wire_type");
+ }
+}
+
+/* Decode string length from stream and return a substream with limited length.
+ * Remember to close the substream using pb_close_string_substream().
+ */
+bool checkreturn pb_make_string_substream(pb_istream_t *stream, pb_istream_t *substream)
+{
+ uint32_t size;
+ if (!pb_decode_varint32(stream, &size))
+ return false;
+
+ *substream = *stream;
+ if (substream->bytes_left < size)
+ PB_RETURN_ERROR(stream, "parent stream too short");
+
+ substream->bytes_left = size;
+ stream->bytes_left -= size;
+ return true;
+}
+
+bool checkreturn pb_close_string_substream(pb_istream_t *stream, pb_istream_t *substream)
+{
+ if (substream->bytes_left) {
+ if (!pb_read(substream, NULL, substream->bytes_left))
+ return false;
+ }
+
+ stream->state = substream->state;
+
+#ifndef PB_NO_ERRMSG
+ stream->errmsg = substream->errmsg;
+#endif
+ return true;
+}
+
+/*************************
+ * Decode a single field *
+ *************************/
+
+static bool checkreturn decode_static_field(pb_istream_t *stream, pb_wire_type_t wire_type, pb_field_iter_t *iter)
+{
+ pb_type_t type;
+ pb_decoder_t func;
+
+ type = iter->pos->type;
+ func = PB_DECODERS[PB_LTYPE(type)];
+
+ switch (PB_HTYPE(type))
+ {
+ case PB_HTYPE_REQUIRED:
+ return func(stream, iter->pos, iter->pData);
+
+ case PB_HTYPE_OPTIONAL:
+ if (iter->pSize != iter->pData)
+ *(bool*)iter->pSize = true;
+ return func(stream, iter->pos, iter->pData);
+
+ case PB_HTYPE_REPEATED:
+ if (wire_type == PB_WT_STRING
+ && PB_LTYPE(type) <= PB_LTYPE_LAST_PACKABLE)
+ {
+ /* Packed array */
+ bool status = true;
+ pb_size_t *size = (pb_size_t*)iter->pSize;
+ pb_istream_t substream;
+ if (!pb_make_string_substream(stream, &substream))
+ return false;
+
+ while (substream.bytes_left > 0 && *size < iter->pos->array_size)
+ {
+ void *pItem = (char*)iter->pData + iter->pos->data_size * (*size);
+ if (!func(&substream, iter->pos, pItem))
+ {
+ status = false;
+ break;
+ }
+ (*size)++;
+ }
+
+ if (substream.bytes_left != 0)
+ PB_RETURN_ERROR(stream, "array overflow");
+ if (!pb_close_string_substream(stream, &substream))
+ return false;
+
+ return status;
+ }
+ else
+ {
+ /* Repeated field */
+ pb_size_t *size = (pb_size_t*)iter->pSize;
+ void *pItem = (char*)iter->pData + iter->pos->data_size * (*size);
+ if (*size >= iter->pos->array_size)
+ PB_RETURN_ERROR(stream, "array overflow");
+
+ (*size)++;
+ return func(stream, iter->pos, pItem);
+ }
+
+ case PB_HTYPE_ONEOF:
+ *(pb_size_t*)iter->pSize = iter->pos->tag;
+ if (PB_LTYPE(type) == PB_LTYPE_SUBMESSAGE)
+ {
+ /* We memset to zero so that any callbacks are set to NULL.
+ * Then set any default values. */
+ memset(iter->pData, 0, iter->pos->data_size);
+ pb_message_set_to_defaults((const pb_field_t*)iter->pos->ptr, iter->pData);
+ }
+ return func(stream, iter->pos, iter->pData);
+
+ default:
+ PB_RETURN_ERROR(stream, "invalid field type");
+ }
+}
+
+#ifdef PB_ENABLE_MALLOC
+/* Allocate storage for the field and store the pointer at iter->pData.
+ * array_size is the number of entries to reserve in an array.
+ * Zero size is not allowed, use pb_free() for releasing.
+ */
+static bool checkreturn allocate_field(pb_istream_t *stream, void *pData, size_t data_size, size_t array_size)
+{
+ void *ptr = *(void**)pData;
+
+ if (data_size == 0 || array_size == 0)
+ PB_RETURN_ERROR(stream, "invalid size");
+
+ /* Check for multiplication overflows.
+ * This code avoids the costly division if the sizes are small enough.
+ * Multiplication is safe as long as only half of bits are set
+ * in either multiplicand.
+ */
+ {
+ const size_t check_limit = (size_t)1 << (sizeof(size_t) * 4);
+ if (data_size >= check_limit || array_size >= check_limit)
+ {
+ const size_t size_max = (size_t)-1;
+ if (size_max / array_size < data_size)
+ {
+ PB_RETURN_ERROR(stream, "size too large");
+ }
+ }
+ }
+
+ /* Allocate new or expand previous allocation */
+ /* Note: on failure the old pointer will remain in the structure,
+ * the message must be freed by caller also on error return. */
+ ptr = pb_realloc(ptr, array_size * data_size);
+ if (ptr == NULL)
+ PB_RETURN_ERROR(stream, "realloc failed");
+
+ *(void**)pData = ptr;
+ return true;
+}
+
+/* Clear a newly allocated item in case it contains a pointer, or is a submessage. */
+static void initialize_pointer_field(void *pItem, pb_field_iter_t *iter)
+{
+ if (PB_LTYPE(iter->pos->type) == PB_LTYPE_STRING ||
+ PB_LTYPE(iter->pos->type) == PB_LTYPE_BYTES)
+ {
+ *(void**)pItem = NULL;
+ }
+ else if (PB_LTYPE(iter->pos->type) == PB_LTYPE_SUBMESSAGE)
+ {
+ pb_message_set_to_defaults((const pb_field_t *) iter->pos->ptr, pItem);
+ }
+}
+#endif
+
+static bool checkreturn decode_pointer_field(pb_istream_t *stream, pb_wire_type_t wire_type, pb_field_iter_t *iter)
+{
+#ifndef PB_ENABLE_MALLOC
+ PB_UNUSED(wire_type);
+ PB_UNUSED(iter);
+ PB_RETURN_ERROR(stream, "no malloc support");
+#else
+ pb_type_t type;
+ pb_decoder_t func;
+
+ type = iter->pos->type;
+ func = PB_DECODERS[PB_LTYPE(type)];
+
+ switch (PB_HTYPE(type))
+ {
+ case PB_HTYPE_REQUIRED:
+ case PB_HTYPE_OPTIONAL:
+ case PB_HTYPE_ONEOF:
+ if (PB_LTYPE(type) == PB_LTYPE_SUBMESSAGE &&
+ *(void**)iter->pData != NULL)
+ {
+ /* Duplicate field, have to release the old allocation first. */
+ pb_release_single_field(iter);
+ }
+
+ if (PB_HTYPE(type) == PB_HTYPE_ONEOF)
+ {
+ *(pb_size_t*)iter->pSize = iter->pos->tag;
+ }
+
+ if (PB_LTYPE(type) == PB_LTYPE_STRING ||
+ PB_LTYPE(type) == PB_LTYPE_BYTES)
+ {
+ return func(stream, iter->pos, iter->pData);
+ }
+ else
+ {
+ if (!allocate_field(stream, iter->pData, iter->pos->data_size, 1))
+ return false;
+
+ initialize_pointer_field(*(void**)iter->pData, iter);
+ return func(stream, iter->pos, *(void**)iter->pData);
+ }
+
+ case PB_HTYPE_REPEATED:
+ if (wire_type == PB_WT_STRING
+ && PB_LTYPE(type) <= PB_LTYPE_LAST_PACKABLE)
+ {
+ /* Packed array, multiple items come in at once. */
+ bool status = true;
+ pb_size_t *size = (pb_size_t*)iter->pSize;
+ size_t allocated_size = *size;
+ void *pItem;
+ pb_istream_t substream;
+
+ if (!pb_make_string_substream(stream, &substream))
+ return false;
+
+ while (substream.bytes_left)
+ {
+ if ((size_t)*size + 1 > allocated_size)
+ {
+ /* Allocate more storage. This tries to guess the
+ * number of remaining entries. Round the division
+ * upwards. */
+ allocated_size += (substream.bytes_left - 1) / iter->pos->data_size + 1;
+
+ if (!allocate_field(&substream, iter->pData, iter->pos->data_size, allocated_size))
+ {
+ status = false;
+ break;
+ }
+ }
+
+ /* Decode the array entry */
+ pItem = *(char**)iter->pData + iter->pos->data_size * (*size);
+ initialize_pointer_field(pItem, iter);
+ if (!func(&substream, iter->pos, pItem))
+ {
+ status = false;
+ break;
+ }
+
+ if (*size == PB_SIZE_MAX)
+ {
+#ifndef PB_NO_ERRMSG
+ stream->errmsg = "too many array entries";
+#endif
+ status = false;
+ break;
+ }
+
+ (*size)++;
+ }
+ if (!pb_close_string_substream(stream, &substream))
+ return false;
+
+ return status;
+ }
+ else
+ {
+ /* Normal repeated field, i.e. only one item at a time. */
+ pb_size_t *size = (pb_size_t*)iter->pSize;
+ void *pItem;
+
+ if (*size == PB_SIZE_MAX)
+ PB_RETURN_ERROR(stream, "too many array entries");
+
+ (*size)++;
+ if (!allocate_field(stream, iter->pData, iter->pos->data_size, *size))
+ return false;
+
+ pItem = *(char**)iter->pData + iter->pos->data_size * (*size - 1);
+ initialize_pointer_field(pItem, iter);
+ return func(stream, iter->pos, pItem);
+ }
+
+ default:
+ PB_RETURN_ERROR(stream, "invalid field type");
+ }
+#endif
+}
+
+static bool checkreturn decode_callback_field(pb_istream_t *stream, pb_wire_type_t wire_type, pb_field_iter_t *iter)
+{
+ pb_callback_t *pCallback = (pb_callback_t*)iter->pData;
+
+#ifdef PB_OLD_CALLBACK_STYLE
+ void *arg = pCallback->arg;
+#else
+ void **arg = &(pCallback->arg);
+#endif
+
+ if (pCallback->funcs.decode == NULL)
+ return pb_skip_field(stream, wire_type);
+
+ if (wire_type == PB_WT_STRING)
+ {
+ pb_istream_t substream;
+
+ if (!pb_make_string_substream(stream, &substream))
+ return false;
+
+ do
+ {
+ if (!pCallback->funcs.decode(&substream, iter->pos, arg))
+ PB_RETURN_ERROR(stream, "callback failed");
+ } while (substream.bytes_left);
+
+ if (!pb_close_string_substream(stream, &substream))
+ return false;
+
+ return true;
+ }
+ else
+ {
+ /* Copy the single scalar value to stack.
+ * This is required so that we can limit the stream length,
+ * which in turn allows to use same callback for packed and
+ * not-packed fields. */
+ pb_istream_t substream;
+ pb_byte_t buffer[10];
+ size_t size = sizeof(buffer);
+
+ if (!read_raw_value(stream, wire_type, buffer, &size))
+ return false;
+ substream = pb_istream_from_buffer(buffer, size);
+
+ return pCallback->funcs.decode(&substream, iter->pos, arg);
+ }
+}
+
+static bool checkreturn decode_field(pb_istream_t *stream, pb_wire_type_t wire_type, pb_field_iter_t *iter)
+{
+#ifdef PB_ENABLE_MALLOC
+ /* When decoding an oneof field, check if there is old data that must be
+ * released first. */
+ if (PB_HTYPE(iter->pos->type) == PB_HTYPE_ONEOF)
+ {
+ if (!pb_release_union_field(stream, iter))
+ return false;
+ }
+#endif
+
+ switch (PB_ATYPE(iter->pos->type))
+ {
+ case PB_ATYPE_STATIC:
+ return decode_static_field(stream, wire_type, iter);
+
+ case PB_ATYPE_POINTER:
+ return decode_pointer_field(stream, wire_type, iter);
+
+ case PB_ATYPE_CALLBACK:
+ return decode_callback_field(stream, wire_type, iter);
+
+ default:
+ PB_RETURN_ERROR(stream, "invalid field type");
+ }
+}
+
+static void iter_from_extension(pb_field_iter_t *iter, pb_extension_t *extension)
+{
+ /* Fake a field iterator for the extension field.
+ * It is not actually safe to advance this iterator, but decode_field
+ * will not even try to. */
+ const pb_field_t *field = (const pb_field_t*)extension->type->arg;
+ (void)pb_field_iter_begin(iter, field, extension->dest);
+ iter->pData = extension->dest;
+ iter->pSize = &extension->found;
+
+ if (PB_ATYPE(field->type) == PB_ATYPE_POINTER)
+ {
+ /* For pointer extensions, the pointer is stored directly
+ * in the extension structure. This avoids having an extra
+ * indirection. */
+ iter->pData = &extension->dest;
+ }
+}
+
+/* Default handler for extension fields. Expects a pb_field_t structure
+ * in extension->type->arg. */
+static bool checkreturn default_extension_decoder(pb_istream_t *stream,
+ pb_extension_t *extension, uint32_t tag, pb_wire_type_t wire_type)
+{
+ const pb_field_t *field = (const pb_field_t*)extension->type->arg;
+ pb_field_iter_t iter;
+
+ if (field->tag != tag)
+ return true;
+
+ iter_from_extension(&iter, extension);
+ extension->found = true;
+ return decode_field(stream, wire_type, &iter);
+}
+
+/* Try to decode an unknown field as an extension field. Tries each extension
+ * decoder in turn, until one of them handles the field or loop ends. */
+static bool checkreturn decode_extension(pb_istream_t *stream,
+ uint32_t tag, pb_wire_type_t wire_type, pb_field_iter_t *iter)
+{
+ pb_extension_t *extension = *(pb_extension_t* const *)iter->pData;
+ size_t pos = stream->bytes_left;
+
+ while (extension != NULL && pos == stream->bytes_left)
+ {
+ bool status;
+ if (extension->type->decode)
+ status = extension->type->decode(stream, extension, tag, wire_type);
+ else
+ status = default_extension_decoder(stream, extension, tag, wire_type);
+
+ if (!status)
+ return false;
+
+ extension = extension->next;
+ }
+
+ return true;
+}
+
+/* Step through the iterator until an extension field is found or until all
+ * entries have been checked. There can be only one extension field per
+ * message. Returns false if no extension field is found. */
+static bool checkreturn find_extension_field(pb_field_iter_t *iter)
+{
+ const pb_field_t *start = iter->pos;
+
+ do {
+ if (PB_LTYPE(iter->pos->type) == PB_LTYPE_EXTENSION)
+ return true;
+ (void)pb_field_iter_next(iter);
+ } while (iter->pos != start);
+
+ return false;
+}
+
+/* Initialize message fields to default values, recursively */
+static void pb_field_set_to_default(pb_field_iter_t *iter)
+{
+ pb_type_t type;
+ type = iter->pos->type;
+
+ if (PB_LTYPE(type) == PB_LTYPE_EXTENSION)
+ {
+ pb_extension_t *ext = *(pb_extension_t* const *)iter->pData;
+ while (ext != NULL)
+ {
+ pb_field_iter_t ext_iter;
+ ext->found = false;
+ iter_from_extension(&ext_iter, ext);
+ pb_field_set_to_default(&ext_iter);
+ ext = ext->next;
+ }
+ }
+ else if (PB_ATYPE(type) == PB_ATYPE_STATIC)
+ {
+ bool init_data = true;
+ if (PB_HTYPE(type) == PB_HTYPE_OPTIONAL && iter->pSize != iter->pData)
+ {
+ /* Set has_field to false. Still initialize the optional field
+ * itself also. */
+ *(bool*)iter->pSize = false;
+ }
+ else if (PB_HTYPE(type) == PB_HTYPE_REPEATED ||
+ PB_HTYPE(type) == PB_HTYPE_ONEOF)
+ {
+ /* REPEATED: Set array count to 0, no need to initialize contents.
+ ONEOF: Set which_field to 0. */
+ *(pb_size_t*)iter->pSize = 0;
+ init_data = false;
+ }
+
+ if (init_data)
+ {
+ if (PB_LTYPE(iter->pos->type) == PB_LTYPE_SUBMESSAGE)
+ {
+ /* Initialize submessage to defaults */
+ pb_message_set_to_defaults((const pb_field_t *) iter->pos->ptr, iter->pData);
+ }
+ else if (iter->pos->ptr != NULL)
+ {
+ /* Initialize to default value */
+ memcpy(iter->pData, iter->pos->ptr, iter->pos->data_size);
+ }
+ else
+ {
+ /* Initialize to zeros */
+ memset(iter->pData, 0, iter->pos->data_size);
+ }
+ }
+ }
+ else if (PB_ATYPE(type) == PB_ATYPE_POINTER)
+ {
+ /* Initialize the pointer to NULL. */
+ *(void**)iter->pData = NULL;
+
+ /* Initialize array count to 0. */
+ if (PB_HTYPE(type) == PB_HTYPE_REPEATED ||
+ PB_HTYPE(type) == PB_HTYPE_ONEOF)
+ {
+ *(pb_size_t*)iter->pSize = 0;
+ }
+ }
+ else if (PB_ATYPE(type) == PB_ATYPE_CALLBACK)
+ {
+ /* Don't overwrite callback */
+ }
+}
+
+static void pb_message_set_to_defaults(const pb_field_t fields[], void *dest_struct)
+{
+ pb_field_iter_t iter;
+
+ if (!pb_field_iter_begin(&iter, fields, dest_struct))
+ return; /* Empty message type */
+
+ do
+ {
+ pb_field_set_to_default(&iter);
+ } while (pb_field_iter_next(&iter));
+}
+
+/*********************
+ * Decode all fields *
+ *********************/
+
+bool checkreturn pb_decode_noinit(pb_istream_t *stream, const pb_field_t fields[], void *dest_struct)
+{
+ uint32_t fields_seen[(PB_MAX_REQUIRED_FIELDS + 31) / 32] = {0, 0};
+ const uint32_t allbits = ~(uint32_t)0;
+ uint32_t extension_range_start = 0;
+ pb_field_iter_t iter;
+
+ /* Return value ignored, as empty message types will be correctly handled by
+ * pb_field_iter_find() anyway. */
+ (void)pb_field_iter_begin(&iter, fields, dest_struct);
+
+ while (stream->bytes_left)
+ {
+ uint32_t tag;
+ pb_wire_type_t wire_type;
+ bool eof;
+
+ if (!pb_decode_tag(stream, &wire_type, &tag, &eof))
+ {
+ if (eof)
+ break;
+ else
+ return false;
+ }
+
+ if (!pb_field_iter_find(&iter, tag))
+ {
+ /* No match found, check if it matches an extension. */
+ if (tag >= extension_range_start)
+ {
+ if (!find_extension_field(&iter))
+ extension_range_start = (uint32_t)-1;
+ else
+ extension_range_start = iter.pos->tag;
+
+ if (tag >= extension_range_start)
+ {
+ size_t pos = stream->bytes_left;
+
+ if (!decode_extension(stream, tag, wire_type, &iter))
+ return false;
+
+ if (pos != stream->bytes_left)
+ {
+ /* The field was handled */
+ continue;
+ }
+ }
+ }
+
+ /* No match found, skip data */
+ if (!pb_skip_field(stream, wire_type))
+ return false;
+ continue;
+ }
+
+ if (PB_HTYPE(iter.pos->type) == PB_HTYPE_REQUIRED
+ && iter.required_field_index < PB_MAX_REQUIRED_FIELDS)
+ {
+ uint32_t tmp = ((uint32_t)1 << (iter.required_field_index & 31));
+ fields_seen[iter.required_field_index >> 5] |= tmp;
+ }
+
+ if (!decode_field(stream, wire_type, &iter))
+ return false;
+ }
+
+ /* Check that all required fields were present. */
+ {
+ /* First figure out the number of required fields by
+ * seeking to the end of the field array. Usually we
+ * are already close to end after decoding.
+ */
+ unsigned req_field_count;
+ pb_type_t last_type;
+ unsigned i;
+ do {
+ req_field_count = iter.required_field_index;
+ last_type = iter.pos->type;
+ } while (pb_field_iter_next(&iter));
+
+ /* Fixup if last field was also required. */
+ if (PB_HTYPE(last_type) == PB_HTYPE_REQUIRED && iter.pos->tag != 0)
+ req_field_count++;
+
+ if (req_field_count > 0)
+ {
+ /* Check the whole words */
+ for (i = 0; i < (req_field_count >> 5); i++)
+ {
+ if (fields_seen[i] != allbits)
+ PB_RETURN_ERROR(stream, "missing required field");
+ }
+
+ /* Check the remaining bits */
+ if (fields_seen[req_field_count >> 5] != (allbits >> (32 - (req_field_count & 31))))
+ PB_RETURN_ERROR(stream, "missing required field");
+ }
+ }
+
+ return true;
+}
+
+bool checkreturn pb_decode(pb_istream_t *stream, const pb_field_t fields[], void *dest_struct)
+{
+ bool status;
+ pb_message_set_to_defaults(fields, dest_struct);
+ status = pb_decode_noinit(stream, fields, dest_struct);
+
+#ifdef PB_ENABLE_MALLOC
+ if (!status)
+ pb_release(fields, dest_struct);
+#endif
+
+ return status;
+}
+
+bool pb_decode_delimited(pb_istream_t *stream, const pb_field_t fields[], void *dest_struct)
+{
+ pb_istream_t substream;
+ bool status;
+
+ if (!pb_make_string_substream(stream, &substream))
+ return false;
+
+ status = pb_decode(&substream, fields, dest_struct);
+
+ if (!pb_close_string_substream(stream, &substream))
+ return false;
+ return status;
+}
+
+#ifdef PB_ENABLE_MALLOC
+/* Given an oneof field, if there has already been a field inside this oneof,
+ * release it before overwriting with a different one. */
+static bool pb_release_union_field(pb_istream_t *stream, pb_field_iter_t *iter)
+{
+ pb_size_t old_tag = *(pb_size_t*)iter->pSize; /* Previous which_ value */
+ pb_size_t new_tag = iter->pos->tag; /* New which_ value */
+
+ if (old_tag == 0)
+ return true; /* Ok, no old data in union */
+
+ if (old_tag == new_tag)
+ return true; /* Ok, old data is of same type => merge */
+
+ /* Release old data. The find can fail if the message struct contains
+ * invalid data. */
+ if (!pb_field_iter_find(iter, old_tag))
+ PB_RETURN_ERROR(stream, "invalid union tag");
+
+ pb_release_single_field(iter);
+
+ /* Restore iterator to where it should be.
+ * This shouldn't fail unless the pb_field_t structure is corrupted. */
+ if (!pb_field_iter_find(iter, new_tag))
+ PB_RETURN_ERROR(stream, "iterator error");
+
+ return true;
+}
+
+static void pb_release_single_field(const pb_field_iter_t *iter)
+{
+ pb_type_t type;
+ type = iter->pos->type;
+
+ if (PB_HTYPE(type) == PB_HTYPE_ONEOF)
+ {
+ if (*(pb_size_t*)iter->pSize != iter->pos->tag)
+ return; /* This is not the current field in the union */
+ }
+
+ /* Release anything contained inside an extension or submsg.
+ * This has to be done even if the submsg itself is statically
+ * allocated. */
+ if (PB_LTYPE(type) == PB_LTYPE_EXTENSION)
+ {
+ /* Release fields from all extensions in the linked list */
+ pb_extension_t *ext = *(pb_extension_t**)iter->pData;
+ while (ext != NULL)
+ {
+ pb_field_iter_t ext_iter;
+ iter_from_extension(&ext_iter, ext);
+ pb_release_single_field(&ext_iter);
+ ext = ext->next;
+ }
+ }
+ else if (PB_LTYPE(type) == PB_LTYPE_SUBMESSAGE)
+ {
+ /* Release fields in submessage or submsg array */
+ void *pItem = iter->pData;
+ pb_size_t count = 1;
+
+ if (PB_ATYPE(type) == PB_ATYPE_POINTER)
+ {
+ pItem = *(void**)iter->pData;
+ }
+
+ if (PB_HTYPE(type) == PB_HTYPE_REPEATED)
+ {
+ count = *(pb_size_t*)iter->pSize;
+
+ if (PB_ATYPE(type) == PB_ATYPE_STATIC && count > iter->pos->array_size)
+ {
+ /* Protect against corrupted _count fields */
+ count = iter->pos->array_size;
+ }
+ }
+
+ if (pItem)
+ {
+ while (count--)
+ {
+ pb_release((const pb_field_t*)iter->pos->ptr, pItem);
+ pItem = (char*)pItem + iter->pos->data_size;
+ }
+ }
+ }
+
+ if (PB_ATYPE(type) == PB_ATYPE_POINTER)
+ {
+ if (PB_HTYPE(type) == PB_HTYPE_REPEATED &&
+ (PB_LTYPE(type) == PB_LTYPE_STRING ||
+ PB_LTYPE(type) == PB_LTYPE_BYTES))
+ {
+ /* Release entries in repeated string or bytes array */
+ void **pItem = *(void***)iter->pData;
+ pb_size_t count = *(pb_size_t*)iter->pSize;
+ while (count--)
+ {
+ pb_free(*pItem);
+ *pItem++ = NULL;
+ }
+ }
+
+ if (PB_HTYPE(type) == PB_HTYPE_REPEATED)
+ {
+ /* We are going to release the array, so set the size to 0 */
+ *(pb_size_t*)iter->pSize = 0;
+ }
+
+ /* Release main item */
+ pb_free(*(void**)iter->pData);
+ *(void**)iter->pData = NULL;
+ }
+}
+
+void pb_release(const pb_field_t fields[], void *dest_struct)
+{
+ pb_field_iter_t iter;
+
+ if (!dest_struct)
+ return; /* Ignore NULL pointers, similar to free() */
+
+ if (!pb_field_iter_begin(&iter, fields, dest_struct))
+ return; /* Empty message type */
+
+ do
+ {
+ pb_release_single_field(&iter);
+ } while (pb_field_iter_next(&iter));
+}
+#endif
+
+/* Field decoders */
+
+bool pb_decode_svarint(pb_istream_t *stream, int64_t *dest)
+{
+ uint64_t value;
+ if (!pb_decode_varint(stream, &value))
+ return false;
+
+ if (value & 1)
+ *dest = (int64_t)(~(value >> 1));
+ else
+ *dest = (int64_t)(value >> 1);
+
+ return true;
+}
+
+bool pb_decode_fixed32(pb_istream_t *stream, void *dest)
+{
+ pb_byte_t bytes[4];
+
+ if (!pb_read(stream, bytes, 4))
+ return false;
+
+ *(uint32_t*)dest = ((uint32_t)bytes[0] << 0) |
+ ((uint32_t)bytes[1] << 8) |
+ ((uint32_t)bytes[2] << 16) |
+ ((uint32_t)bytes[3] << 24);
+ return true;
+}
+
+bool pb_decode_fixed64(pb_istream_t *stream, void *dest)
+{
+ pb_byte_t bytes[8];
+
+ if (!pb_read(stream, bytes, 8))
+ return false;
+
+ *(uint64_t*)dest = ((uint64_t)bytes[0] << 0) |
+ ((uint64_t)bytes[1] << 8) |
+ ((uint64_t)bytes[2] << 16) |
+ ((uint64_t)bytes[3] << 24) |
+ ((uint64_t)bytes[4] << 32) |
+ ((uint64_t)bytes[5] << 40) |
+ ((uint64_t)bytes[6] << 48) |
+ ((uint64_t)bytes[7] << 56);
+
+ return true;
+}
+
+static bool checkreturn pb_dec_varint(pb_istream_t *stream, const pb_field_t *field, void *dest)
+{
+ uint64_t value;
+ int64_t svalue;
+ int64_t clamped;
+ if (!pb_decode_varint(stream, &value))
+ return false;
+
+ /* See issue 97: Google's C++ protobuf allows negative varint values to
+ * be cast as int32_t, instead of the int64_t that should be used when
+ * encoding. Previous nanopb versions had a bug in encoding. In order to
+ * not break decoding of such messages, we cast <=32 bit fields to
+ * int32_t first to get the sign correct.
+ */
+ if (field->data_size == sizeof(int64_t))
+ svalue = (int64_t)value;
+ else
+ svalue = (int32_t)value;
+
+ /* Cast to the proper field size, while checking for overflows */
+ if (field->data_size == sizeof(int64_t))
+ clamped = *(int64_t*)dest = svalue;
+ else if (field->data_size == sizeof(int32_t))
+ clamped = *(int32_t*)dest = (int32_t)svalue;
+ else if (field->data_size == sizeof(int_least16_t))
+ clamped = *(int_least16_t*)dest = (int_least16_t)svalue;
+ else if (field->data_size == sizeof(int_least8_t))
+ clamped = *(int_least8_t*)dest = (int_least8_t)svalue;
+ else
+ PB_RETURN_ERROR(stream, "invalid data_size");
+
+ if (clamped != svalue)
+ PB_RETURN_ERROR(stream, "integer too large");
+
+ return true;
+}
+
+static bool checkreturn pb_dec_uvarint(pb_istream_t *stream, const pb_field_t *field, void *dest)
+{
+ uint64_t value, clamped;
+ if (!pb_decode_varint(stream, &value))
+ return false;
+
+ /* Cast to the proper field size, while checking for overflows */
+ if (field->data_size == sizeof(uint64_t))
+ clamped = *(uint64_t*)dest = value;
+ else if (field->data_size == sizeof(uint32_t))
+ clamped = *(uint32_t*)dest = (uint32_t)value;
+ else if (field->data_size == sizeof(uint_least16_t))
+ clamped = *(uint_least16_t*)dest = (uint_least16_t)value;
+ else if (field->data_size == sizeof(uint_least8_t))
+ clamped = *(uint_least8_t*)dest = (uint_least8_t)value;
+ else
+ PB_RETURN_ERROR(stream, "invalid data_size");
+
+ if (clamped != value)
+ PB_RETURN_ERROR(stream, "integer too large");
+
+ return true;
+}
+
+static bool checkreturn pb_dec_svarint(pb_istream_t *stream, const pb_field_t *field, void *dest)
+{
+ int64_t value, clamped;
+ if (!pb_decode_svarint(stream, &value))
+ return false;
+
+ /* Cast to the proper field size, while checking for overflows */
+ if (field->data_size == sizeof(int64_t))
+ clamped = *(int64_t*)dest = value;
+ else if (field->data_size == sizeof(int32_t))
+ clamped = *(int32_t*)dest = (int32_t)value;
+ else if (field->data_size == sizeof(int_least16_t))
+ clamped = *(int_least16_t*)dest = (int_least16_t)value;
+ else if (field->data_size == sizeof(int_least8_t))
+ clamped = *(int_least8_t*)dest = (int_least8_t)value;
+ else
+ PB_RETURN_ERROR(stream, "invalid data_size");
+
+ if (clamped != value)
+ PB_RETURN_ERROR(stream, "integer too large");
+
+ return true;
+}
+
+static bool checkreturn pb_dec_fixed32(pb_istream_t *stream, const pb_field_t *field, void *dest)
+{
+ PB_UNUSED(field);
+ return pb_decode_fixed32(stream, dest);
+}
+
+static bool checkreturn pb_dec_fixed64(pb_istream_t *stream, const pb_field_t *field, void *dest)
+{
+ PB_UNUSED(field);
+ return pb_decode_fixed64(stream, dest);
+}
+
+static bool checkreturn pb_dec_bytes(pb_istream_t *stream, const pb_field_t *field, void *dest)
+{
+ uint32_t size;
+ size_t alloc_size;
+ pb_bytes_array_t *bdest;
+
+ if (!pb_decode_varint32(stream, &size))
+ return false;
+
+ if (size > PB_SIZE_MAX)
+ PB_RETURN_ERROR(stream, "bytes overflow");
+
+ alloc_size = PB_BYTES_ARRAY_T_ALLOCSIZE(size);
+ if (size > alloc_size)
+ PB_RETURN_ERROR(stream, "size too large");
+
+ if (PB_ATYPE(field->type) == PB_ATYPE_POINTER)
+ {
+#ifndef PB_ENABLE_MALLOC
+ PB_RETURN_ERROR(stream, "no malloc support");
+#else
+ if (!allocate_field(stream, dest, alloc_size, 1))
+ return false;
+ bdest = *(pb_bytes_array_t**)dest;
+#endif
+ }
+ else
+ {
+ if (alloc_size > field->data_size)
+ PB_RETURN_ERROR(stream, "bytes overflow");
+ bdest = (pb_bytes_array_t*)dest;
+ }
+
+ bdest->size = (pb_size_t)size;
+ return pb_read(stream, bdest->bytes, size);
+}
+
+static bool checkreturn pb_dec_string(pb_istream_t *stream, const pb_field_t *field, void *dest)
+{
+ uint32_t size;
+ size_t alloc_size;
+ bool status;
+ if (!pb_decode_varint32(stream, &size))
+ return false;
+
+ /* Space for null terminator */
+ alloc_size = size + 1;
+
+ if (alloc_size < size)
+ PB_RETURN_ERROR(stream, "size too large");
+
+ if (PB_ATYPE(field->type) == PB_ATYPE_POINTER)
+ {
+#ifndef PB_ENABLE_MALLOC
+ PB_RETURN_ERROR(stream, "no malloc support");
+#else
+ if (!allocate_field(stream, dest, alloc_size, 1))
+ return false;
+ dest = *(void**)dest;
+#endif
+ }
+ else
+ {
+ if (alloc_size > field->data_size)
+ PB_RETURN_ERROR(stream, "string overflow");
+ }
+
+ status = pb_read(stream, (pb_byte_t*)dest, size);
+ *((pb_byte_t*)dest + size) = 0;
+ return status;
+}
+
+static bool checkreturn pb_dec_submessage(pb_istream_t *stream, const pb_field_t *field, void *dest)
+{
+ bool status;
+ pb_istream_t substream;
+ const pb_field_t* submsg_fields = (const pb_field_t*)field->ptr;
+
+ if (!pb_make_string_substream(stream, &substream))
+ return false;
+
+ if (field->ptr == NULL)
+ PB_RETURN_ERROR(stream, "invalid field descriptor");
+
+ /* New array entries need to be initialized, while required and optional
+ * submessages have already been initialized in the top-level pb_decode. */
+ if (PB_HTYPE(field->type) == PB_HTYPE_REPEATED)
+ status = pb_decode(&substream, submsg_fields, dest);
+ else
+ status = pb_decode_noinit(&substream, submsg_fields, dest);
+
+ if (!pb_close_string_substream(stream, &substream))
+ return false;
+ return status;
+}
+
+static bool checkreturn pb_dec_fixed_length_bytes(pb_istream_t *stream, const pb_field_t *field, void *dest)
+{
+ uint32_t size;
+
+ if (!pb_decode_varint32(stream, &size))
+ return false;
+
+ if (size > PB_SIZE_MAX)
+ PB_RETURN_ERROR(stream, "bytes overflow");
+
+ if (size == 0)
+ {
+ /* As a special case, treat empty bytes string as all zeros for fixed_length_bytes. */
+ memset(dest, 0, field->data_size);
+ return true;
+ }
+
+ if (size != field->data_size)
+ PB_RETURN_ERROR(stream, "incorrect fixed length bytes size");
+
+ return pb_read(stream, (pb_byte_t*)dest, field->data_size);
+}
fnp / wl-app.git / blobdiff