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/*
* upb - a minimalist implementation of protocol buffers.
*
* Copyright (c) 2008-2011 Google Inc. See LICENSE for details.
* Author: Josh Haberman <jhaberman@gmail.com>
*/
#include <inttypes.h>
#include <setjmp.h>
#include <stddef.h>
#include <stdlib.h>
#include "upb/bytestream.h"
#include "upb/pb/decoder.h"
#include "upb/pb/varint.h"
#define UPB_NONDELIMITED (0xffffffffffffffffULL)
/* upb_pbdecoder ****************************************************************/
struct dasm_State;
typedef struct {
const upb_fielddef *f;
uint64_t end_ofs;
uint32_t group_fieldnum; // UINT32_MAX for non-groups.
bool is_sequence; // frame represents seq or submsg/str? (f might be both).
bool is_packed; // true for packed primitive sequences.
} frame;
struct upb_pbdecoder {
// Where we push parsed data (not owned).
upb_sink *sink;
// Current input buffer and its stream offset.
const char *buf, *ptr, *end, *checkpoint;
uint64_t bufstart_ofs;
// Buffer for residual bytes not parsed from the previous buffer.
char residual[16];
char *residual_end;
// Stores the user buffer passed to our decode function.
const char *buf_param;
size_t size_param;
// Equal to size_param while we are in the residual buf, 0 otherwise.
size_t userbuf_remaining;
// Used to temporarily store the return value before calling longjmp().
size_t ret;
// End of the delimited region, relative to ptr, or NULL if not in this buf.
const char *delim_end;
#ifdef UPB_USE_JIT_X64
// For JIT, which doesn't do bounds checks in the middle of parsing a field.
const char *jit_end, *effective_end; // == MIN(jit_end, delim_end)
// Used momentarily by the generated code to store a value while a user
// function is called.
uint32_t tmp_len;
const void *saved_rbp;
#endif
// Our internal stack.
frame *top, *limit;
frame stack[UPB_MAX_NESTING];
// For exiting the decoder on error.
jmp_buf exitjmp;
};
typedef struct {
// The top-level handlers that this plan calls into. We own a ref.
const upb_handlers *dest_handlers;
#ifdef UPB_USE_JIT_X64
// JIT-generated machine code (else NULL).
char *jit_code;
size_t jit_size;
char *debug_info;
// For storing upb_jitmsginfo, which contains per-msg runtime data needed
// by the JIT.
// Maps upb_handlers* -> upb_jitmsginfo.
upb_inttable msginfo;
// The following members are used only while the JIT is being built.
// This pointer is allocated by dasm_init() and freed by dasm_free().
struct dasm_State *dynasm;
// For storing pclabel bases while we are building the JIT.
// Maps (upb_handlers* or upb_fielddef*) -> int32 pclabel_base
upb_inttable pclabels;
// This is not the same as len(pclabels) because the table only contains base
// offsets for each def, but each def can have many pclabels.
uint32_t pclabel_count;
#endif
} decoderplan;
typedef struct {
uint8_t native_wire_type;
bool is_numeric;
} upb_decoder_typeinfo;
static const upb_decoder_typeinfo upb_decoder_types[] = {
{UPB_WIRE_TYPE_END_GROUP, false}, // ENDGROUP
{UPB_WIRE_TYPE_64BIT, true}, // DOUBLE
{UPB_WIRE_TYPE_32BIT, true}, // FLOAT
{UPB_WIRE_TYPE_VARINT, true}, // INT64
{UPB_WIRE_TYPE_VARINT, true}, // UINT64
{UPB_WIRE_TYPE_VARINT, true}, // INT32
{UPB_WIRE_TYPE_64BIT, true}, // FIXED64
{UPB_WIRE_TYPE_32BIT, true}, // FIXED32
{UPB_WIRE_TYPE_VARINT, true}, // BOOL
{UPB_WIRE_TYPE_DELIMITED, false}, // STRING
{UPB_WIRE_TYPE_START_GROUP, false}, // GROUP
{UPB_WIRE_TYPE_DELIMITED, false}, // MESSAGE
{UPB_WIRE_TYPE_DELIMITED, false}, // BYTES
{UPB_WIRE_TYPE_VARINT, true}, // UINT32
{UPB_WIRE_TYPE_VARINT, true}, // ENUM
{UPB_WIRE_TYPE_32BIT, true}, // SFIXED32
{UPB_WIRE_TYPE_64BIT, true}, // SFIXED64
{UPB_WIRE_TYPE_VARINT, true}, // SINT32
{UPB_WIRE_TYPE_VARINT, true}, // SINT64
};
static upb_selector_t getselector(const upb_fielddef *f,
upb_handlertype_t type) {
upb_selector_t selector;
bool ok = upb_getselector(f, type, &selector);
UPB_ASSERT_VAR(ok, ok);
return selector;
}
/* decoderplan ****************************************************************/
#ifdef UPB_USE_JIT_X64
// These defines are necessary for DynASM codegen.
// See dynasm/dasm_proto.h for more info.
#define Dst_DECL decoderplan *plan
#define Dst_REF (plan->dynasm)
#define Dst (plan)
// In debug mode, make DynASM do internal checks (must be defined before any
// dasm header is included.
#ifndef NDEBUG
#define DASM_CHECKS
#endif
#include "dynasm/dasm_proto.h"
#include "upb/pb/decoder_x64.h"
#endif
void freeplan(void *_p) {
decoderplan *p = _p;
upb_handlers_unref(p->dest_handlers, p);
#ifdef UPB_USE_JIT_X64
if (p->jit_code) upb_decoderplan_freejit(p);
#endif
free(p);
}
static decoderplan *getdecoderplan(const upb_handlers *h) {
if (upb_handlers_frametype(h) != upb_pbdecoder_getframetype())
return NULL;
upb_selector_t sel;
if (!upb_getselector(UPB_BYTESTREAM_BYTES, UPB_HANDLER_STRING, &sel))
return NULL;
return upb_handlers_gethandlerdata(h, sel);
}
bool upb_pbdecoder_isdecoder(const upb_handlers *h) {
return getdecoderplan(h) != NULL;
}
bool upb_pbdecoder_hasjitcode(const upb_handlers *h) {
#ifdef UPB_USE_JIT_X64
decoderplan *p = getdecoderplan(h);
if (!p) return false;
return p->jit_code != NULL;
#else
UPB_UNUSED(h);
return false;
#endif
}
const upb_handlers *upb_pbdecoder_getdesthandlers(const upb_handlers *h) {
decoderplan *p = getdecoderplan(h);
if (!p) return NULL;
return p->dest_handlers;
}
/* upb_pbdecoder ****************************************************************/
static bool in_residual_buf(const upb_pbdecoder *d, const char *p);
// It's unfortunate that we have to micro-manage the compiler this way,
// especially since this tuning is necessarily specific to one hardware
// configuration. But emperically on a Core i7, performance increases 30-50%
// with these annotations. Every instance where these appear, gcc 4.2.1 made
// the wrong decision and degraded performance in benchmarks.
#define FORCEINLINE static inline __attribute__((always_inline))
#define NOINLINE static __attribute__((noinline))
static upb_status *decoder_status(upb_pbdecoder *d) {
// TODO(haberman): encapsulate this access to pipeline->status, but not sure
// exactly what that interface should look like.
return &d->sink->pipeline_->status_;
}
UPB_NORETURN static void exitjmp(upb_pbdecoder *d) {
_longjmp(d->exitjmp, 1);
}
UPB_NORETURN static void abortjmp(upb_pbdecoder *d, const char *msg) {
d->ret = in_residual_buf(d, d->checkpoint) ? 0 : (d->checkpoint - d->buf);
upb_status_seterrliteral(decoder_status(d), msg);
exitjmp(d);
}
/* Buffering ******************************************************************/
// We operate on one buffer at a time, which is either the user's buffer passed
// to our "decode" callback or some residual bytes from the previous buffer.
// How many bytes can be safely read from d->ptr.
static size_t bufleft(upb_pbdecoder *d) {
assert(d->end >= d->ptr);
return d->end - d->ptr;
}
// Overall offset of d->ptr.
uint64_t offset(const upb_pbdecoder *d) {
return d->bufstart_ofs + (d->ptr - d->buf);
}
// Advances d->ptr.
static void advance(upb_pbdecoder *d, size_t len) {
assert(bufleft(d) >= len);
d->ptr += len;
}
// Commits d->ptr progress; should be called when an entire atomic value
// (ie tag+value) has been successfully consumed.
static void checkpoint(upb_pbdecoder *d) {
d->checkpoint = d->ptr;
}
static bool in_buf(const char *p, const char *buf, const char *end) {
return p >= buf && p <= end;
}
static bool in_residual_buf(const upb_pbdecoder *d, const char *p) {
return in_buf(p, d->residual, d->residual_end);
}
// Calculates the delim_end value, which represents a combination of the
// current buffer and the stack, so must be called whenever either is updated.
static void set_delim_end(upb_pbdecoder *d) {
frame *f = d->top;
size_t delimlen = f->end_ofs - d->bufstart_ofs;
size_t buflen = d->end - d->buf;
d->delim_end = (f->end_ofs != UPB_NONDELIMITED && delimlen <= buflen) ?
d->buf + delimlen : NULL; // NULL if not in this buf.
}
static void switchtobuf(upb_pbdecoder *d, const char *buf, const char *end) {
d->ptr = buf;
d->buf = buf;
d->end = end;
set_delim_end(d);
#ifdef UPB_USE_JIT_X64
// If we start parsing a value, we can parse up to 20 bytes without
// having to bounds-check anything (2 10-byte varints). Since the
// JIT bounds-checks only *between* values (and for strings), the
// JIT bails if there are not 20 bytes available.
d->jit_end = d->end - 20;
#endif
}
static void suspendjmp(upb_pbdecoder *d) {
switchtobuf(d, d->residual, d->residual_end);
exitjmp(d);
}
static void advancetobuf(upb_pbdecoder *d, const char *buf, size_t len) {
assert(d->ptr == d->end);
d->bufstart_ofs += (d->ptr - d->buf);
switchtobuf(d, buf, buf + len);
}
static void skip(upb_pbdecoder *d, size_t bytes) {
size_t avail = bufleft(d);
size_t total_avail = avail + d->userbuf_remaining;
if (avail >= bytes) {
// Skipped data is all in current buffer.
advance(d, bytes);
} else if (total_avail >= bytes) {
// Skipped data is all in residual buf and param buffer.
assert(in_residual_buf(d, d->ptr));
advance(d, avail);
advancetobuf(d, d->buf_param, d->size_param);
d->userbuf_remaining = 0;
advance(d, bytes - avail);
} else {
// Skipped data extends beyond currently available buffers.
// TODO: we need to do a checkdelim() equivalent that pops any frames that
// we just skipped past.
d->bufstart_ofs = offset(d) + bytes;
d->residual_end = d->residual;
d->ret += bytes - total_avail;
suspendjmp(d);
}
}
static void consumebytes(upb_pbdecoder *d, void *buf, size_t bytes) {
assert(bytes <= bufleft(d));
memcpy(buf, d->ptr, bytes);
advance(d, bytes);
}
NOINLINE void getbytes_slow(upb_pbdecoder *d, void *buf, size_t bytes) {
const size_t avail = bufleft(d);
if (avail + d->userbuf_remaining >= bytes) {
// Remaining residual buffer and param buffer together can satisfy.
// (We are only called from getbytes() which has already verified that
// the current buffer alone cannot satisfy).
assert(in_residual_buf(d, d->ptr));
consumebytes(d, buf, avail);
advancetobuf(d, d->buf_param, d->size_param);
consumebytes(d, buf + avail, bytes - avail);
d->userbuf_remaining = 0;
} else {
// There is not enough remaining data, save residual bytes (if any)
// starting at the last committed checkpoint and exit.
if (in_buf(d->checkpoint, d->buf_param, d->buf_param + d->size_param)) {
// Checkpoint was in user buf; old residual bytes not needed.
d->ptr = d->checkpoint;
size_t save = bufleft(d);
assert(save <= sizeof(d->residual));
memcpy(d->residual, d->ptr, save);
d->residual_end = d->residual + save;
d->bufstart_ofs = offset(d);
} else {
// Checkpoint was in residual buf; append user byte(s) to residual buf.
assert(d->checkpoint == d->residual);
assert((d->residual_end - d->residual) + d->size_param <=
sizeof(d->residual));
if (!in_residual_buf(d, d->ptr)) {
d->bufstart_ofs -= (d->residual_end - d->residual);
}
memcpy(d->residual_end, d->buf_param, d->size_param);
d->residual_end += d->size_param;
}
suspendjmp(d);
}
}
FORCEINLINE void getbytes(upb_pbdecoder *d, void *buf, size_t bytes) {
if (bufleft(d) >= bytes) {
// Buffer has enough data to satisfy.
consumebytes(d, buf, bytes);
} else {
getbytes_slow(d, buf, bytes);
}
}
FORCEINLINE uint8_t getbyte(upb_pbdecoder *d) {
uint8_t byte;
getbytes(d, &byte, 1);
return byte;
}
/* Decoding of wire types *****************************************************/
NOINLINE uint64_t decode_varint_slow(upb_pbdecoder *d) {
uint8_t byte = 0x80;
uint64_t u64 = 0;
int bitpos;
for(bitpos = 0; bitpos < 70 && (byte & 0x80); bitpos += 7) {
u64 |= ((uint64_t)((byte = getbyte(d)) & 0x7F)) << bitpos;
}
if(bitpos == 70 && (byte & 0x80))
abortjmp(d, "Unterminated varint");
return u64;
}
NOINLINE uint32_t decode_v32_slow(upb_pbdecoder *d) {
uint64_t u64 = decode_varint_slow(d);
if (u64 > UINT32_MAX) abortjmp(d, "Unterminated 32-bit varint");
return (uint32_t)u64;
}
// For tags and delimited lengths, which must be <=32bit and are usually small.
FORCEINLINE uint32_t decode_v32(upb_pbdecoder *d) {
// Nearly all will be either 1 byte (1-16) or 2 bytes (17-2048).
if (bufleft(d) >= 2) {
uint32_t ret = d->ptr[0] & 0x7f;
if ((d->ptr[0] & 0x80) == 0) {
advance(d, 1);
return ret;
}
ret |= (d->ptr[1] & 0x7f) << 7;
if ((d->ptr[1] & 0x80) == 0) {
advance(d, 2);
return ret;
}
}
return decode_v32_slow(d);
}
FORCEINLINE uint64_t decode_varint(upb_pbdecoder *d) {
if (bufleft(d) >= 10) {
// Fast case.
upb_decoderet r = upb_vdecode_fast(d->ptr);
if (r.p == NULL) abortjmp(d, "Unterminated varint");
advance(d, r.p - d->ptr);
return r.val;
} else {
// Slow case -- varint spans buffer seam.
return decode_varint_slow(d);
}
}
FORCEINLINE uint32_t decode_fixed32(upb_pbdecoder *d) {
uint32_t u32;
getbytes(d, &u32, 4);
return u32; // TODO: proper byte swapping for big-endian machines.
}
FORCEINLINE uint64_t decode_fixed64(upb_pbdecoder *d) {
uint64_t u64;
getbytes(d, &u64, 8);
return u64; // TODO: proper byte swapping for big-endian machines.
}
static void push(upb_pbdecoder *d, const upb_fielddef *f, bool is_sequence,
bool is_packed, int32_t group_fieldnum, uint64_t end) {
frame *fr = d->top + 1;
if (fr >= d->limit) abortjmp(d, "Nesting too deep.");
fr->f = f;
fr->is_sequence = is_sequence;
fr->is_packed = is_packed;
fr->end_ofs = end;
fr->group_fieldnum = group_fieldnum;
d->top = fr;
set_delim_end(d);
}
static void push_msg(upb_pbdecoder *d, const upb_fielddef *f, uint64_t end) {
if (!upb_sink_startsubmsg(d->sink, getselector(f, UPB_HANDLER_STARTSUBMSG)))
abortjmp(d, "startsubmsg failed.");
int32_t group_fieldnum = (end == UPB_NONDELIMITED) ?
(int32_t)upb_fielddef_number(f) : -1;
push(d, f, false, false, group_fieldnum, end);
}
static void push_seq(upb_pbdecoder *d, const upb_fielddef *f, bool packed,
uint64_t end_ofs) {
if (!upb_sink_startseq(d->sink, getselector(f, UPB_HANDLER_STARTSEQ)))
abortjmp(d, "startseq failed.");
push(d, f, true, packed, -1, end_ofs);
}
static void push_str(upb_pbdecoder *d, const upb_fielddef *f, size_t len,
uint64_t end) {
if (!upb_sink_startstr(d->sink, getselector(f, UPB_HANDLER_STARTSTR), len))
abortjmp(d, "startseq failed.");
push(d, f, false, false, -1, end);
}
static void pop_submsg(upb_pbdecoder *d) {
upb_sink_endsubmsg(d->sink, getselector(d->top->f, UPB_HANDLER_ENDSUBMSG));
d->top--;
set_delim_end(d);
}
static void pop_seq(upb_pbdecoder *d) {
upb_sink_endseq(d->sink, getselector(d->top->f, UPB_HANDLER_ENDSEQ));
d->top--;
set_delim_end(d);
}
static void pop_string(upb_pbdecoder *d) {
upb_sink_endstr(d->sink, getselector(d->top->f, UPB_HANDLER_ENDSTR));
d->top--;
set_delim_end(d);
}
static void checkdelim(upb_pbdecoder *d) {
while (d->delim_end && d->ptr >= d->delim_end) {
// TODO(haberman): not sure what to do about this; if we detect this error
// we can possibly violate the promise that errors are always signaled by a
// short "parsed byte" count (because all bytes might have been successfully
// parsed prior to detecting this error).
// if (d->ptr > d->delim_end) abortjmp(d, "Bad submessage end");
if (d->top->is_sequence) {
pop_seq(d);
} else {
pop_submsg(d);
}
}
}
/* Decoding of .proto types ***************************************************/
// Technically, we are losing data if we see a 32-bit varint that is not
// properly sign-extended. We could detect this and error about the data loss,
// but proto2 does not do this, so we pass.
#define T(type, sel, wt, name, convfunc) \
static void decode_ ## type(upb_pbdecoder *d, const upb_fielddef *f) { \
upb_sink_put ## name(d->sink, getselector(f, UPB_HANDLER_ ## sel), \
(convfunc)(decode_ ## wt(d))); \
} \
static double upb_asdouble(uint64_t n) { double d; memcpy(&d, &n, 8); return d; }
static float upb_asfloat(uint32_t n) { float f; memcpy(&f, &n, 4); return f; }
T(INT32, INT32, varint, int32, int32_t)
T(INT64, INT64, varint, int64, int64_t)
T(UINT32, UINT32, varint, uint32, uint32_t)
T(UINT64, UINT64, varint, uint64, uint64_t)
T(FIXED32, UINT32, fixed32, uint32, uint32_t)
T(FIXED64, UINT64, fixed64, uint64, uint64_t)
T(SFIXED32, INT32, fixed32, int32, int32_t)
T(SFIXED64, INT64, fixed64, int64, int64_t)
T(BOOL, BOOL, varint, bool, bool)
T(ENUM, INT32, varint, int32, int32_t)
T(DOUBLE, DOUBLE, fixed64, double, upb_asdouble)
T(FLOAT, FLOAT, fixed32, float, upb_asfloat)
T(SINT32, INT32, varint, int32, upb_zzdec_32)
T(SINT64, INT64, varint, int64, upb_zzdec_64)
#undef T
static void decode_GROUP(upb_pbdecoder *d, const upb_fielddef *f) {
push_msg(d, f, UPB_NONDELIMITED);
}
static void decode_MESSAGE(upb_pbdecoder *d, const upb_fielddef *f) {
uint32_t len = decode_v32(d);
push_msg(d, f, offset(d) + len);
}
static void decode_STRING(upb_pbdecoder *d, const upb_fielddef *f) {
uint32_t strlen = decode_v32(d);
if (strlen <= bufleft(d)) {
upb_sink_startstr(d->sink, getselector(f, UPB_HANDLER_STARTSTR), strlen);
if (strlen)
upb_sink_putstring(d->sink, getselector(f, UPB_HANDLER_STRING),
d->ptr, strlen);
upb_sink_endstr(d->sink, getselector(f, UPB_HANDLER_ENDSTR));
advance(d, strlen);
} else {
// Buffer ends in the middle of the string; need to push a decoder frame
// for it.
push_str(d, f, strlen, offset(d) + strlen);
if (bufleft(d)) {
upb_sink_putstring(d->sink, getselector(f, UPB_HANDLER_STRING),
d->ptr, bufleft(d));
advance(d, bufleft(d));
}
d->bufstart_ofs = offset(d);
d->residual_end = d->residual;
suspendjmp(d);
}
}
/* The main decoding loop *****************************************************/
static const upb_fielddef *decode_tag(upb_pbdecoder *d) {
while (1) {
uint32_t tag = decode_v32(d);
uint8_t wire_type = tag & 0x7;
uint32_t fieldnum = tag >> 3; const upb_fielddef *f = NULL;
const upb_handlers *h = upb_sinkframe_handlers(upb_sink_top(d->sink));
f = upb_msgdef_itof(upb_handlers_msgdef(h), fieldnum);
bool packed = false;
if (f) {
// Wire type check.
upb_descriptortype_t type = upb_fielddef_descriptortype(f);
if (wire_type == upb_decoder_types[type].native_wire_type) {
// Wire type is ok.
} else if ((wire_type == UPB_WIRE_TYPE_DELIMITED &&
upb_decoder_types[type].is_numeric)) {
// Wire type is ok (and packed).
packed = true;
} else {
f = NULL;
}
}
// There are no explicit "startseq" or "endseq" markers in protobuf
// streams, so we have to infer them by noticing when a repeated field
// starts or ends.
frame *fr = d->top;
if (fr->is_sequence && fr->f != f) {
pop_seq(d);
fr = d->top;
}
if (f && upb_fielddef_isseq(f) && !fr->is_sequence) {
if (packed) {
uint32_t len = decode_v32(d);
push_seq(d, f, true, offset(d) + len);
checkpoint(d);
} else {
push_seq(d, f, false, fr->end_ofs);
}
}
if (f) return f;
// Unknown field or ENDGROUP.
if (fieldnum == 0 || fieldnum > UPB_MAX_FIELDNUMBER)
abortjmp(d, "Invalid field number");
switch (wire_type) {
case UPB_WIRE_TYPE_VARINT: decode_varint(d); break;
case UPB_WIRE_TYPE_32BIT: skip(d, 4); break;
case UPB_WIRE_TYPE_64BIT: skip(d, 8); break;
case UPB_WIRE_TYPE_DELIMITED: skip(d, decode_v32(d)); break;
case UPB_WIRE_TYPE_START_GROUP:
abortjmp(d, "Can't handle unknown groups yet");
case UPB_WIRE_TYPE_END_GROUP:
if (fieldnum != fr->group_fieldnum)
abortjmp(d, "Unmatched ENDGROUP tag");
pop_submsg(d);
break;
default:
abortjmp(d, "Invalid wire type");
}
// TODO: deliver to unknown field callback.
checkpoint(d);
checkdelim(d);
}
}
void *start(const upb_sinkframe *fr, size_t size_hint) {
UPB_UNUSED(size_hint);
upb_pbdecoder *d = upb_sinkframe_userdata(fr);
assert(d);
assert(d->sink);
upb_sink_startmsg(d->sink);
return d;
}
bool end(const upb_sinkframe *fr) {
upb_pbdecoder *d = upb_sinkframe_userdata(fr);
if (d->residual_end > d->residual) {
// We have preserved bytes.
upb_status_seterrliteral(decoder_status(d), "Unexpected EOF");
return false;
}
// We may need to dispatch a top-level implicit frame.
if (d->top == d->stack + 1 &&
d->top->is_sequence &&
!d->top->is_packed) {
assert(upb_sinkframe_depth(upb_sink_top(d->sink)) == 1);
pop_seq(d);
}
if (d->top != d->stack) {
upb_status_seterrliteral(
decoder_status(d), "Ended inside delimited field.");
return false;
}
upb_sink_endmsg(d->sink);
return true;
}
size_t decode(const upb_sinkframe *fr, const char *buf, size_t size) {
upb_pbdecoder *d = upb_sinkframe_userdata(fr);
decoderplan *plan = upb_sinkframe_handlerdata(fr);
UPB_UNUSED(plan);
assert(upb_sinkframe_handlers(upb_sink_top(d->sink)) == plan->dest_handlers);
if (size == 0) return 0;
// Assume we'll consume the whole buffer unless this is overwritten.
d->ret = size;
if (_setjmp(d->exitjmp)) {
// Hit end-of-buffer or error.
return d->ret;
}
d->buf_param = buf;
d->size_param = size;
if (d->residual_end > d->residual) {
// We have residual bytes from the last buffer.
d->userbuf_remaining = size;
} else {
d->userbuf_remaining = 0;
advancetobuf(d, buf, size);
if (d->top != d->stack &&
upb_fielddef_isstring(d->top->f) &&
!d->top->is_sequence) {
// Last buffer ended in the middle of a string; deliver more of it.
size_t len = d->top->end_ofs - offset(d);
if (size >= len) {
upb_sink_putstring(d->sink, getselector(d->top->f, UPB_HANDLER_STRING),
d->ptr, len);
advance(d, len);
pop_string(d);
} else {
upb_sink_putstring(d->sink, getselector(d->top->f, UPB_HANDLER_STRING),
d->ptr, size);
advance(d, size);
d->residual_end = d->residual;
advancetobuf(d, d->residual, 0);
return size;
}
}
}
checkpoint(d);
const upb_fielddef *f = d->top->f;
while(1) {
#ifdef UPB_USE_JIT_X64
upb_decoder_enterjit(d, plan);
checkpoint(d);
set_delim_end(d); // JIT doesn't keep this current.
#endif
checkdelim(d);
if (!d->top->is_packed) {
f = decode_tag(d);
}
switch (upb_fielddef_descriptortype(f)) {
case UPB_DESCRIPTOR_TYPE_DOUBLE: decode_DOUBLE(d, f); break;
case UPB_DESCRIPTOR_TYPE_FLOAT: decode_FLOAT(d, f); break;
case UPB_DESCRIPTOR_TYPE_INT64: decode_INT64(d, f); break;
case UPB_DESCRIPTOR_TYPE_UINT64: decode_UINT64(d, f); break;
case UPB_DESCRIPTOR_TYPE_INT32: decode_INT32(d, f); break;
case UPB_DESCRIPTOR_TYPE_FIXED64: decode_FIXED64(d, f); break;
case UPB_DESCRIPTOR_TYPE_FIXED32: decode_FIXED32(d, f); break;
case UPB_DESCRIPTOR_TYPE_BOOL: decode_BOOL(d, f); break;
case UPB_DESCRIPTOR_TYPE_STRING: UPB_FALLTHROUGH_INTENDED;
case UPB_DESCRIPTOR_TYPE_BYTES: decode_STRING(d, f); break;
case UPB_DESCRIPTOR_TYPE_GROUP: decode_GROUP(d, f); break;
case UPB_DESCRIPTOR_TYPE_MESSAGE: decode_MESSAGE(d, f); break;
case UPB_DESCRIPTOR_TYPE_UINT32: decode_UINT32(d, f); break;
case UPB_DESCRIPTOR_TYPE_ENUM: decode_ENUM(d, f); break;
case UPB_DESCRIPTOR_TYPE_SFIXED32: decode_SFIXED32(d, f); break;
case UPB_DESCRIPTOR_TYPE_SFIXED64: decode_SFIXED64(d, f); break;
case UPB_DESCRIPTOR_TYPE_SINT32: decode_SINT32(d, f); break;
case UPB_DESCRIPTOR_TYPE_SINT64: decode_SINT64(d, f); break;
}
checkpoint(d);
}
}
void init(void *_d) {
upb_pbdecoder *d = _d;
d->limit = &d->stack[UPB_MAX_NESTING];
d->sink = NULL;
// reset() must be called before decoding; this is guaranteed by assert() in
// start().
}
void reset(void *_d) {
upb_pbdecoder *d = _d;
d->top = d->stack;
d->top->is_sequence = false;
d->top->is_packed = false;
d->top->group_fieldnum = UINT32_MAX;
d->top->end_ofs = UPB_NONDELIMITED;
d->bufstart_ofs = 0;
d->ptr = d->residual;
d->buf = d->residual;
d->end = d->residual;
d->residual_end = d->residual;
}
bool upb_pbdecoder_resetsink(upb_pbdecoder *d, upb_sink* sink) {
// TODO(haberman): typecheck the sink, and test whether the decoder is in the
// middle of decoding. Return false if either assumption is violated.
d->sink = sink;
reset(d);
return true;
}
const upb_frametype upb_pbdecoder_frametype = {
sizeof(upb_pbdecoder),
init,
NULL,
reset,
};
const upb_frametype *upb_pbdecoder_getframetype() {
return &upb_pbdecoder_frametype;
}
const upb_handlers *upb_pbdecoder_gethandlers(const upb_handlers *dest,
bool allowjit,
const void *owner) {
UPB_UNUSED(allowjit);
decoderplan *p = malloc(sizeof(*p));
assert(upb_handlers_isfrozen(dest));
p->dest_handlers = dest;
upb_handlers_ref(dest, p);
#ifdef UPB_USE_JIT_X64
p->jit_code = NULL;
if (allowjit) upb_decoderplan_makejit(p);
#endif
upb_handlers *h = upb_handlers_new(
UPB_BYTESTREAM, &upb_pbdecoder_frametype, owner);
upb_handlers_setstartstr(h, UPB_BYTESTREAM_BYTES, start, NULL, NULL);
upb_handlers_setstring(h, UPB_BYTESTREAM_BYTES, decode, p, freeplan);
upb_handlers_setendstr(h, UPB_BYTESTREAM_BYTES, end, NULL, NULL);
return h;
}
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