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protobuf/upb/decode.c

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#include "upb/decode.h"
#include <setjmp.h>
#include <string.h>
#include "upb/decode.int.h"
#include "upb/upb.h"
#include "upb/upb.int.h"
/* Must be last. */
#include "upb/port_def.inc"
/* Maps descriptor type -> elem_size_lg2. */
static const uint8_t desctype_to_elem_size_lg2[] = {
-1, /* invalid descriptor type */
3, /* DOUBLE */
2, /* FLOAT */
3, /* INT64 */
3, /* UINT64 */
2, /* INT32 */
3, /* FIXED64 */
2, /* FIXED32 */
0, /* BOOL */
UPB_SIZE(3, 4), /* STRING */
UPB_SIZE(2, 3), /* GROUP */
UPB_SIZE(2, 3), /* MESSAGE */
UPB_SIZE(3, 4), /* BYTES */
2, /* UINT32 */
2, /* ENUM */
2, /* SFIXED32 */
3, /* SFIXED64 */
2, /* SINT32 */
3, /* SINT64 */
};
/* Maps descriptor type -> upb map size. */
static const uint8_t desctype_to_mapsize[] = {
-1, /* invalid descriptor type */
8, /* DOUBLE */
4, /* FLOAT */
8, /* INT64 */
8, /* UINT64 */
4, /* INT32 */
8, /* FIXED64 */
4, /* FIXED32 */
1, /* BOOL */
UPB_MAPTYPE_STRING, /* STRING */
sizeof(void *), /* GROUP */
sizeof(void *), /* MESSAGE */
UPB_MAPTYPE_STRING, /* BYTES */
4, /* UINT32 */
4, /* ENUM */
4, /* SFIXED32 */
8, /* SFIXED64 */
4, /* SINT32 */
8, /* SINT64 */
};
static const unsigned fixed32_ok = (1 << UPB_DTYPE_FLOAT) |
(1 << UPB_DTYPE_FIXED32) |
(1 << UPB_DTYPE_SFIXED32);
static const unsigned fixed64_ok = (1 << UPB_DTYPE_DOUBLE) |
(1 << UPB_DTYPE_FIXED64) |
(1 << UPB_DTYPE_SFIXED64);
/* Op: an action to be performed for a wire-type/field-type combination. */
#define OP_SCALAR_LG2(n) (n) /* n in [0, 2, 3] => op in [0, 2, 3] */
#define OP_STRING 4
#define OP_BYTES 5
#define OP_SUBMSG 6
/* Ops above are scalar-only. Repeated fields can use any op. */
#define OP_FIXPCK_LG2(n) (n + 5) /* n in [2, 3] => op in [7, 8] */
#define OP_VARPCK_LG2(n) (n + 9) /* n in [0, 2, 3] => op in [9, 11, 12] */
static const int8_t varint_ops[19] = {
-1, /* field not found */
-1, /* DOUBLE */
-1, /* FLOAT */
OP_SCALAR_LG2(3), /* INT64 */
OP_SCALAR_LG2(3), /* UINT64 */
OP_SCALAR_LG2(2), /* INT32 */
-1, /* FIXED64 */
-1, /* FIXED32 */
OP_SCALAR_LG2(0), /* BOOL */
-1, /* STRING */
-1, /* GROUP */
-1, /* MESSAGE */
-1, /* BYTES */
OP_SCALAR_LG2(2), /* UINT32 */
OP_SCALAR_LG2(2), /* ENUM */
-1, /* SFIXED32 */
-1, /* SFIXED64 */
OP_SCALAR_LG2(2), /* SINT32 */
OP_SCALAR_LG2(3), /* SINT64 */
};
static const int8_t delim_ops[37] = {
/* For non-repeated field type. */
-1, /* field not found */
-1, /* DOUBLE */
-1, /* FLOAT */
-1, /* INT64 */
-1, /* UINT64 */
-1, /* INT32 */
-1, /* FIXED64 */
-1, /* FIXED32 */
-1, /* BOOL */
OP_STRING, /* STRING */
-1, /* GROUP */
OP_SUBMSG, /* MESSAGE */
OP_BYTES, /* BYTES */
-1, /* UINT32 */
-1, /* ENUM */
-1, /* SFIXED32 */
-1, /* SFIXED64 */
-1, /* SINT32 */
-1, /* SINT64 */
/* For repeated field type. */
OP_FIXPCK_LG2(3), /* REPEATED DOUBLE */
OP_FIXPCK_LG2(2), /* REPEATED FLOAT */
OP_VARPCK_LG2(3), /* REPEATED INT64 */
OP_VARPCK_LG2(3), /* REPEATED UINT64 */
OP_VARPCK_LG2(2), /* REPEATED INT32 */
OP_FIXPCK_LG2(3), /* REPEATED FIXED64 */
OP_FIXPCK_LG2(2), /* REPEATED FIXED32 */
OP_VARPCK_LG2(0), /* REPEATED BOOL */
OP_STRING, /* REPEATED STRING */
OP_SUBMSG, /* REPEATED GROUP */
OP_SUBMSG, /* REPEATED MESSAGE */
OP_BYTES, /* REPEATED BYTES */
OP_VARPCK_LG2(2), /* REPEATED UINT32 */
OP_VARPCK_LG2(2), /* REPEATED ENUM */
OP_FIXPCK_LG2(2), /* REPEATED SFIXED32 */
OP_FIXPCK_LG2(3), /* REPEATED SFIXED64 */
OP_VARPCK_LG2(2), /* REPEATED SINT32 */
OP_VARPCK_LG2(3), /* REPEATED SINT64 */
};
typedef union {
bool bool_val;
uint32_t uint32_val;
uint64_t uint64_val;
uint32_t size;
} wireval;
static const char *decode_msg(upb_decstate *d, const char *ptr, upb_msg *msg,
const upb_msglayout *layout);
UPB_NORETURN static void decode_err(upb_decstate *d) { UPB_LONGJMP(d->err, 1); }
const char *fastdecode_err(upb_decstate *d) {
longjmp(d->err, 1);
return NULL;
}
const uint8_t upb_utf8_offsets[] = {
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
2, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
4, 4, 4, 4, 4, 4, 4, 4, 0, 0, 0, 0, 0, 0, 0, 0,
};
static void decode_verifyutf8(upb_decstate *d, const char *buf, int len) {
if (!decode_verifyutf8_inl(buf, len)) decode_err(d);
}
static bool decode_reserve(upb_decstate *d, upb_array *arr, size_t elem) {
bool need_realloc = arr->size - arr->len < elem;
if (need_realloc && !_upb_array_realloc(arr, arr->len + elem, &d->arena)) {
decode_err(d);
}
return need_realloc;
}
typedef struct {
const char *ptr;
uint64_t val;
} decode_vret;
UPB_NOINLINE
static decode_vret decode_longvarint64(const char *ptr, uint64_t val) {
decode_vret ret = {NULL, 0};
uint64_t byte;
int i;
for (i = 1; i < 10; i++) {
byte = (uint8_t)ptr[i];
val += (byte - 1) << (i * 7);
if (!(byte & 0x80)) {
ret.ptr = ptr + i + 1;
ret.val = val;
return ret;
}
}
return ret;
}
UPB_FORCEINLINE
static const char *decode_varint64(upb_decstate *d, const char *ptr,
uint64_t *val) {
uint64_t byte = (uint8_t)*ptr;
if (UPB_LIKELY((byte & 0x80) == 0)) {
*val = byte;
return ptr + 1;
} else {
decode_vret res = decode_longvarint64(ptr, byte);
if (!res.ptr) decode_err(d);
*val = res.val;
return res.ptr;
}
}
UPB_FORCEINLINE
static const char *decode_tag(upb_decstate *d, const char *ptr,
uint32_t *val) {
uint64_t byte = (uint8_t)*ptr;
if (UPB_LIKELY((byte & 0x80) == 0)) {
*val = byte;
return ptr + 1;
} else {
const char *start = ptr;
decode_vret res = decode_longvarint64(ptr, byte);
ptr = res.ptr;
*val = res.val;
if (!ptr || *val > UINT32_MAX || ptr - start > 5) decode_err(d);
return ptr;
}
}
static void decode_munge(int type, wireval *val) {
switch (type) {
case UPB_DESCRIPTOR_TYPE_BOOL:
val->bool_val = val->uint64_val != 0;
break;
case UPB_DESCRIPTOR_TYPE_SINT32: {
uint32_t n = val->uint32_val;
val->uint32_val = (n >> 1) ^ -(int32_t)(n & 1);
break;
}
case UPB_DESCRIPTOR_TYPE_SINT64: {
uint64_t n = val->uint64_val;
val->uint64_val = (n >> 1) ^ -(int64_t)(n & 1);
break;
}
case UPB_DESCRIPTOR_TYPE_INT32:
case UPB_DESCRIPTOR_TYPE_UINT32:
if (!_upb_isle()) {
/* The next stage will memcpy(dst, &val, 4) */
val->uint32_val = val->uint64_val;
}
break;
}
}
static const upb_msglayout_field *upb_find_field(const upb_msglayout *l,
uint32_t field_number) {
static upb_msglayout_field none = {0, 0, 0, 0, 0, 0};
/* Lots of optimization opportunities here. */
int i;
if (l == NULL) return &none;
for (i = 0; i < l->field_count; i++) {
if (l->fields[i].number == field_number) {
return &l->fields[i];
}
}
return &none; /* Unknown field. */
}
static upb_msg *decode_newsubmsg(upb_decstate *d, const upb_msglayout *layout,
const upb_msglayout_field *field) {
const upb_msglayout *subl = layout->submsgs[field->submsg_index];
return _upb_msg_new_inl(subl, &d->arena);
}
UPB_NOINLINE
const char *decode_isdonefallback(upb_decstate *d, const char *ptr,
int overrun) {
ptr = decode_isdonefallback_inl(d, ptr, overrun);
if (ptr == NULL) {
decode_err(d);
}
return ptr;
}
static const char *decode_readstr(upb_decstate *d, const char *ptr, int size,
upb_strview *str) {
if (d->alias) {
str->data = ptr;
} else {
char *data = upb_arena_malloc(&d->arena, size);
if (!data) decode_err(d);
memcpy(data, ptr, size);
str->data = data;
}
str->size = size;
return ptr + size;
}
UPB_FORCEINLINE
static const char *decode_tosubmsg(upb_decstate *d, const char *ptr,
upb_msg *submsg, const upb_msglayout *layout,
const upb_msglayout_field *field, int size) {
const upb_msglayout *subl = layout->submsgs[field->submsg_index];
int saved_delta = decode_pushlimit(d, ptr, size);
if (--d->depth < 0) decode_err(d);
if (!decode_isdone(d, &ptr)) {
ptr = decode_msg(d, ptr, submsg, subl);
}
if (d->end_group != DECODE_NOGROUP) decode_err(d);
decode_poplimit(d, ptr, saved_delta);
d->depth++;
return ptr;
}
UPB_FORCEINLINE
static const char *decode_group(upb_decstate *d, const char *ptr,
upb_msg *submsg, const upb_msglayout *subl,
uint32_t number) {
if (--d->depth < 0) decode_err(d);
if (decode_isdone(d, &ptr)) {
decode_err(d);
}
ptr = decode_msg(d, ptr, submsg, subl);
if (d->end_group != number) decode_err(d);
d->end_group = DECODE_NOGROUP;
d->depth++;
return ptr;
}
UPB_FORCEINLINE
static const char *decode_togroup(upb_decstate *d, const char *ptr,
upb_msg *submsg, const upb_msglayout *layout,
const upb_msglayout_field *field) {
const upb_msglayout *subl = layout->submsgs[field->submsg_index];
return decode_group(d, ptr, submsg, subl, field->number);
}
static const char *decode_toarray(upb_decstate *d, const char *ptr,
upb_msg *msg, const upb_msglayout *layout,
const upb_msglayout_field *field, wireval val,
int op) {
upb_array **arrp = UPB_PTR_AT(msg, field->offset, void);
upb_array *arr = *arrp;
void *mem;
if (arr) {
decode_reserve(d, arr, 1);
} else {
size_t lg2 = desctype_to_elem_size_lg2[field->descriptortype];
arr = _upb_array_new(&d->arena, 4, lg2);
if (!arr) decode_err(d);
*arrp = arr;
}
switch (op) {
case OP_SCALAR_LG2(0):
case OP_SCALAR_LG2(2):
case OP_SCALAR_LG2(3):
/* Append scalar value. */
mem = UPB_PTR_AT(_upb_array_ptr(arr), arr->len << op, void);
arr->len++;
memcpy(mem, &val, 1 << op);
return ptr;
case OP_STRING:
decode_verifyutf8(d, ptr, val.size);
/* Fallthrough. */
case OP_BYTES: {
/* Append bytes. */
upb_strview *str = (upb_strview*)_upb_array_ptr(arr) + arr->len;
arr->len++;
return decode_readstr(d, ptr, val.size, str);
}
case OP_SUBMSG: {
/* Append submessage / group. */
upb_msg *submsg = decode_newsubmsg(d, layout, field);
*UPB_PTR_AT(_upb_array_ptr(arr), arr->len * sizeof(void *), upb_msg *) =
submsg;
arr->len++;
if (UPB_UNLIKELY(field->descriptortype == UPB_DTYPE_GROUP)) {
return decode_togroup(d, ptr, submsg, layout, field);
} else {
return decode_tosubmsg(d, ptr, submsg, layout, field, val.size);
}
}
case OP_FIXPCK_LG2(2):
case OP_FIXPCK_LG2(3): {
/* Fixed packed. */
int lg2 = op - OP_FIXPCK_LG2(0);
int mask = (1 << lg2) - 1;
size_t count = val.size >> lg2;
if ((val.size & mask) != 0) {
decode_err(d); /* Length isn't a round multiple of elem size. */
}
decode_reserve(d, arr, count);
mem = UPB_PTR_AT(_upb_array_ptr(arr), arr->len << lg2, void);
arr->len += count;
memcpy(mem, ptr, val.size); /* XXX: ptr boundary. */
return ptr + val.size;
}
case OP_VARPCK_LG2(0):
case OP_VARPCK_LG2(2):
case OP_VARPCK_LG2(3): {
/* Varint packed. */
int lg2 = op - OP_VARPCK_LG2(0);
int scale = 1 << lg2;
int saved_limit = decode_pushlimit(d, ptr, val.size);
char *out = UPB_PTR_AT(_upb_array_ptr(arr), arr->len << lg2, void);
while (!decode_isdone(d, &ptr)) {
wireval elem;
ptr = decode_varint64(d, ptr, &elem.uint64_val);
decode_munge(field->descriptortype, &elem);
if (decode_reserve(d, arr, 1)) {
out = UPB_PTR_AT(_upb_array_ptr(arr), arr->len << lg2, void);
}
arr->len++;
memcpy(out, &elem, scale);
out += scale;
}
decode_poplimit(d, ptr, saved_limit);
return ptr;
}
default:
UPB_UNREACHABLE();
}
}
static const char *decode_tomap(upb_decstate *d, const char *ptr, upb_msg *msg,
const upb_msglayout *layout,
const upb_msglayout_field *field, wireval val) {
upb_map **map_p = UPB_PTR_AT(msg, field->offset, upb_map *);
upb_map *map = *map_p;
upb_map_entry ent;
const upb_msglayout *entry = layout->submsgs[field->submsg_index];
if (!map) {
/* Lazily create map. */
const upb_msglayout *entry = layout->submsgs[field->submsg_index];
const upb_msglayout_field *key_field = &entry->fields[0];
const upb_msglayout_field *val_field = &entry->fields[1];
char key_size = desctype_to_mapsize[key_field->descriptortype];
char val_size = desctype_to_mapsize[val_field->descriptortype];
UPB_ASSERT(key_field->offset == 0);
UPB_ASSERT(val_field->offset == sizeof(upb_strview));
map = _upb_map_new(&d->arena, key_size, val_size);
*map_p = map;
}
/* Parse map entry. */
memset(&ent, 0, sizeof(ent));
if (entry->fields[1].descriptortype == UPB_DESCRIPTOR_TYPE_MESSAGE ||
entry->fields[1].descriptortype == UPB_DESCRIPTOR_TYPE_GROUP) {
/* Create proactively to handle the case where it doesn't appear. */
ent.v.val = upb_value_ptr(_upb_msg_new(entry->submsgs[0], &d->arena));
}
ptr = decode_tosubmsg(d, ptr, &ent.k, layout, field, val.size);
_upb_map_set(map, &ent.k, map->key_size, &ent.v, map->val_size, &d->arena);
return ptr;
}
static const char *decode_tomsg(upb_decstate *d, const char *ptr, upb_msg *msg,
const upb_msglayout *layout,
const upb_msglayout_field *field, wireval val,
int op) {
void *mem = UPB_PTR_AT(msg, field->offset, void);
int type = field->descriptortype;
/* Set presence if necessary. */
if (field->presence < 0) {
/* Oneof case */
uint32_t *oneof_case = _upb_oneofcase_field(msg, field);
if (op == OP_SUBMSG && *oneof_case != field->number) {
memset(mem, 0, sizeof(void*));
}
*oneof_case = field->number;
} else if (field->presence > 0) {
_upb_sethas_field(msg, field);
}
/* Store into message. */
switch (op) {
case OP_SUBMSG: {
upb_msg **submsgp = mem;
upb_msg *submsg = *submsgp;
if (!submsg) {
submsg = decode_newsubmsg(d, layout, field);
*submsgp = submsg;
}
if (UPB_UNLIKELY(type == UPB_DTYPE_GROUP)) {
ptr = decode_togroup(d, ptr, submsg, layout, field);
} else {
ptr = decode_tosubmsg(d, ptr, submsg, layout, field, val.size);
}
break;
}
case OP_STRING:
decode_verifyutf8(d, ptr, val.size);
/* Fallthrough. */
case OP_BYTES:
return decode_readstr(d, ptr, val.size, mem);
case OP_SCALAR_LG2(3):
memcpy(mem, &val, 8);
break;
case OP_SCALAR_LG2(2):
memcpy(mem, &val, 4);
break;
case OP_SCALAR_LG2(0):
memcpy(mem, &val, 1);
break;
default:
UPB_UNREACHABLE();
}
return ptr;
}
UPB_FORCEINLINE
static bool decode_tryfastdispatch(upb_decstate *d, const char **ptr,
upb_msg *msg, const upb_msglayout *layout) {
#if UPB_FASTTABLE
if (layout && layout->table_mask != (unsigned char)-1) {
uint16_t tag = fastdecode_loadtag(*ptr);
intptr_t table = decode_totable(layout);
*ptr = fastdecode_tagdispatch(d, *ptr, msg, table, 0, tag);
return true;
}
#endif
return false;
}
UPB_NOINLINE
static const char *decode_msg(upb_decstate *d, const char *ptr, upb_msg *msg,
const upb_msglayout *layout) {
while (true) {
uint32_t tag;
const upb_msglayout_field *field;
int field_number;
int wire_type;
const char *field_start = ptr;
wireval val;
int op;
UPB_ASSERT(ptr < d->limit_ptr);
ptr = decode_tag(d, ptr, &tag);
field_number = tag >> 3;
wire_type = tag & 7;
field = upb_find_field(layout, field_number);
switch (wire_type) {
case UPB_WIRE_TYPE_VARINT:
ptr = decode_varint64(d, ptr, &val.uint64_val);
op = varint_ops[field->descriptortype];
decode_munge(field->descriptortype, &val);
break;
case UPB_WIRE_TYPE_32BIT:
memcpy(&val.uint32_val, ptr, 4);
val.uint32_val = _upb_be_swap32(val.uint32_val);
ptr += 4;
op = OP_SCALAR_LG2(2);
if (((1 << field->descriptortype) & fixed32_ok) == 0) goto unknown;
break;
case UPB_WIRE_TYPE_64BIT:
memcpy(&val.uint64_val, ptr, 8);
val.uint64_val = _upb_be_swap64(val.uint64_val);
ptr += 8;
op = OP_SCALAR_LG2(3);
if (((1 << field->descriptortype) & fixed64_ok) == 0) goto unknown;
break;
case UPB_WIRE_TYPE_DELIMITED: {
int ndx = field->descriptortype;
uint64_t size;
if (_upb_isrepeated(field)) ndx += 18;
ptr = decode_varint64(d, ptr, &size);
if (size >= INT32_MAX ||
ptr - d->end + (int32_t)size > d->limit) {
decode_err(d); /* Length overflow. */
}
op = delim_ops[ndx];
val.size = size;
break;
}
case UPB_WIRE_TYPE_START_GROUP:
val.uint32_val = field_number;
op = OP_SUBMSG;
if (field->descriptortype != UPB_DTYPE_GROUP) goto unknown;
break;
case UPB_WIRE_TYPE_END_GROUP:
d->end_group = field_number;
return ptr;
default:
decode_err(d);
}
if (op >= 0) {
/* Parse, using op for dispatch. */
switch (field->label) {
case UPB_LABEL_REPEATED:
case _UPB_LABEL_PACKED:
ptr = decode_toarray(d, ptr, msg, layout, field, val, op);
break;
case _UPB_LABEL_MAP:
ptr = decode_tomap(d, ptr, msg, layout, field, val);
break;
default:
ptr = decode_tomsg(d, ptr, msg, layout, field, val, op);
break;
}
} else {
unknown:
/* Skip unknown field. */
if (field_number == 0) decode_err(d);
if (wire_type == UPB_WIRE_TYPE_DELIMITED) ptr += val.size;
if (msg) {
if (wire_type == UPB_WIRE_TYPE_START_GROUP) {
d->unknown = field_start;
d->unknown_msg = msg;
ptr = decode_group(d, ptr, NULL, NULL, field_number);
d->unknown_msg = NULL;
field_start = d->unknown;
}
if (!_upb_msg_addunknown(msg, field_start, ptr - field_start,
&d->arena)) {
decode_err(d);
}
} else if (wire_type == UPB_WIRE_TYPE_START_GROUP) {
ptr = decode_group(d, ptr, NULL, NULL, field_number);
}
}
if (decode_isdone(d, &ptr)) return ptr;
if (decode_tryfastdispatch(d, &ptr, msg, layout)) return ptr;
}
}
const char *fastdecode_generic(struct upb_decstate *d, const char *ptr,
upb_msg *msg, intptr_t table, uint64_t hasbits,
uint64_t data) {
(void)data;
*(uint32_t*)msg |= hasbits;
return decode_msg(d, ptr, msg, decode_totablep(table));
}
bool _upb_decode(const char *buf, size_t size, void *msg,
const upb_msglayout *l, upb_arena *arena, int options) {
bool ok;
upb_decstate state;
unsigned depth = (unsigned)options >> 16;
if (size == 0) {
return true;
} else if (size <= 16) {
memset(&state.patch, 0, 32);
memcpy(&state.patch, buf, size);
buf = state.patch;
state.end = buf + size;
state.limit = 0;
state.alias = false;
} else {
state.end = buf + size - 16;
state.limit = 16;
state.alias = options & UPB_DECODE_ALIAS;
}
state.limit_ptr = state.end;
state.unknown_msg = NULL;
state.depth = depth ? depth : 64;
state.end_group = DECODE_NOGROUP;
state.arena.head = arena->head;
state.arena.last_size = arena->last_size;
state.arena.parent = arena;
if (UPB_UNLIKELY(UPB_SETJMP(state.err))) {
ok = false;
} else {
if (!decode_tryfastdispatch(&state, &buf, msg, l)) {
decode_msg(&state, buf, msg, l);
}
ok = state.end_group == DECODE_NOGROUP;
}
arena->head.ptr = state.arena.head.ptr;
arena->head.end = state.arena.head.end;
return ok;
}
#undef OP_SCALAR_LG2
#undef OP_FIXPCK_LG2
#undef OP_VARPCK_LG2
#undef OP_STRING
#undef OP_SUBMSG