diff options
Diffstat (limited to 'upb/pb/decoder.c')
-rw-r--r-- | upb/pb/decoder.c | 914 |
1 files changed, 563 insertions, 351 deletions
diff --git a/upb/pb/decoder.c b/upb/pb/decoder.c index 065c495..2bfc717 100644 --- a/upb/pb/decoder.c +++ b/upb/pb/decoder.c @@ -6,12 +6,101 @@ */ #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; @@ -39,12 +128,21 @@ static const upb_decoder_typeinfo upb_decoder_types[] = { {UPB_WIRE_TYPE_VARINT, true}, // SINT64 }; -/* upb_decoderplan ************************************************************/ +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 upb_decoderplan *plan +#define Dst_DECL decoderplan *plan #define Dst_REF (plan->dynasm) #define Dst (plan) @@ -58,39 +156,49 @@ static const upb_decoder_typeinfo upb_decoder_types[] = { #include "upb/pb/decoder_x64.h" #endif -upb_decoderplan *upb_decoderplan_new(const upb_handlers *h, bool allowjit) { - UPB_UNUSED(allowjit); - upb_decoderplan *p = malloc(sizeof(*p)); - assert(upb_handlers_isfrozen(h)); - p->handlers = h; - upb_handlers_ref(h, p); -#ifdef UPB_USE_JIT_X64 - p->jit_code = NULL; - if (allowjit) upb_decoderplan_makejit(p); -#endif - return p; -} - -void upb_decoderplan_unref(upb_decoderplan *p) { - // TODO: make truly refcounted. - upb_handlers_unref(p->handlers, p); +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); } -bool upb_decoderplan_hasjitcode(upb_decoderplan *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 - (void)p; + 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 ****************************************************************/ -/* upb_decoder ****************************************************************/ +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 @@ -100,98 +208,73 @@ bool upb_decoderplan_hasjitcode(upb_decoderplan *p) { #define FORCEINLINE static inline __attribute__((always_inline)) #define NOINLINE static __attribute__((noinline)) -UPB_NORETURN static void upb_decoder_exitjmp(upb_decoder *d) { - // Resumable decoder would back out to completed_ptr (and possibly get a - // previous buffer). - _longjmp(d->exitjmp, 1); +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 upb_decoder_exitjmp2(void *d) { - upb_decoder_exitjmp(d); + +UPB_NORETURN static void exitjmp(upb_pbdecoder *d) { + _longjmp(d->exitjmp, 1); } -UPB_NORETURN static void upb_decoder_abortjmp(upb_decoder *d, const char *msg) { - upb_status_seterrliteral(&d->status, msg); - upb_decoder_exitjmp(d); + +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 may be a subset of the currently -// loaded byteregion data. When data for the buffer is completely gone we pull -// the next one. When we've committed our progress we discard any previous -// buffers' regions. +// 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. -static size_t upb_decoder_bufleft(upb_decoder *d) { +// 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; } -static void upb_decoder_advance(upb_decoder *d, size_t len) { - assert(upb_decoder_bufleft(d) >= len); +// 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; } -uint64_t upb_decoder_offset(upb_decoder *d) { - return d->bufstart_ofs + (d->ptr - d->buf); +// 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; } -uint64_t upb_decoder_bufendofs(upb_decoder *d) { - return d->bufstart_ofs + (d->end - d->buf); +static bool in_buf(const char *p, const char *buf, const char *end) { + return p >= buf && p <= end; } -static bool upb_decoder_islegalend(upb_decoder *d) { - if (d->top == d->stack) return true; - if (d->top - 1 == d->stack && - d->top->is_sequence && !d->top->is_packed) return true; - return false; +static bool in_residual_buf(const upb_pbdecoder *d, const char *p) { + return in_buf(p, d->residual, d->residual_end); } -// Calculates derived values that we cache for speed. These reflect a -// combination of the current buffer and the stack, so must be called whenever -// either is updated. -static void upb_decoder_setmsgend(upb_decoder *d) { - upb_decoder_frame *f = d->top; +// 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. - d->top_is_packed = f->is_packed; -} - -static void upb_decoder_skiptonewbuf(upb_decoder *d, uint64_t ofs) { - assert(ofs >= upb_decoder_offset(d)); - if (ofs > upb_byteregion_endofs(d->input)) - upb_decoder_abortjmp(d, "Unexpected EOF"); - d->buf = NULL; - d->ptr = NULL; - d->end = NULL; - d->delim_end = NULL; -#ifdef UPB_USE_JIT_X64 - d->jit_end = NULL; -#endif - d->bufstart_ofs = ofs; } -static bool upb_trypullbuf(upb_decoder *d) { - assert(upb_decoder_bufleft(d) == 0); - upb_decoder_skiptonewbuf(d, upb_decoder_offset(d)); - if (upb_byteregion_available(d->input, d->bufstart_ofs) == 0) { - switch (upb_byteregion_fetch(d->input)) { - case UPB_BYTE_OK: - assert(upb_byteregion_available(d->input, d->bufstart_ofs) > 0); - break; - case UPB_BYTE_EOF: return false; - case UPB_BYTE_ERROR: upb_decoder_abortjmp(d, "I/O error in input"); - // Decoder resuming is not yet supported. - case UPB_BYTE_WOULDBLOCK: - upb_decoder_abortjmp(d, "Input returned WOULDBLOCK"); - } - } - size_t len; - d->buf = upb_byteregion_getptr(d->input, d->bufstart_ofs, &len); - assert(len > 0); - d->ptr = d->buf; - d->end = d->buf + len; - upb_decoder_setmsgend(d); +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 @@ -199,172 +282,232 @@ static bool upb_trypullbuf(upb_decoder *d) { // JIT bails if there are not 20 bytes available. d->jit_end = d->end - 20; #endif - assert(upb_decoder_bufleft(d) > 0); - return true; } -static void upb_pullbuf(upb_decoder *d) { - if (!upb_trypullbuf(d)) upb_decoder_abortjmp(d, "Unexpected EOF"); +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(len >= 0); + 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); } -static void upb_decoder_checkpoint(upb_decoder *d) { - upb_byteregion_discard(d->input, upb_decoder_offset(d)); +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); + } } -static void upb_decoder_discardto(upb_decoder *d, uint64_t ofs) { - if (ofs <= upb_decoder_bufendofs(d)) { - upb_decoder_advance(d, ofs - upb_decoder_offset(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 { - upb_decoder_skiptonewbuf(d, ofs); + getbytes_slow(d, buf, bytes); } - upb_decoder_checkpoint(d); } -static void upb_decoder_discard(upb_decoder *d, size_t bytes) { - upb_decoder_discardto(d, upb_decoder_offset(d) + bytes); +FORCEINLINE uint8_t getbyte(upb_pbdecoder *d) { + uint8_t byte; + getbytes(d, &byte, 1); + return byte; } /* Decoding of wire types *****************************************************/ -NOINLINE uint64_t upb_decode_varint_slow(upb_decoder *d) { +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) { - if (upb_decoder_bufleft(d) == 0) upb_pullbuf(d); - u64 |= ((uint64_t)(byte = *d->ptr) & 0x7F) << bitpos; - upb_decoder_advance(d, 1); + u64 |= ((uint64_t)((byte = getbyte(d)) & 0x7F)) << bitpos; } if(bitpos == 70 && (byte & 0x80)) - upb_decoder_abortjmp(d, "Unterminated varint"); + 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 upb_decode_varint32(upb_decoder *d) { - const char *p = d->ptr; - uint32_t ret; - uint64_t u64; +FORCEINLINE uint32_t decode_v32(upb_pbdecoder *d) { // Nearly all will be either 1 byte (1-16) or 2 bytes (17-2048). - if (upb_decoder_bufleft(d) < 2) goto slow; // unlikely. - ret = *p & 0x7f; - if ((*(p++) & 0x80) == 0) goto done; // predictable if fields are in order - ret |= (*p & 0x7f) << 7; - if ((*(p++) & 0x80) == 0) goto done; // likely -slow: - u64 = upb_decode_varint_slow(d); - if (u64 > UINT32_MAX) upb_decoder_abortjmp(d, "Unterminated 32-bit varint"); - ret = (uint32_t)u64; - p = d->ptr; // Turn the next line into a nop. -done: - upb_decoder_advance(d, p - d->ptr); - return ret; -} - -// Returns true on success or false if we've hit a valid EOF. -FORCEINLINE bool upb_trydecode_varint32(upb_decoder *d, uint32_t *val) { - if (upb_decoder_bufleft(d) == 0 && - upb_decoder_islegalend(d) && - !upb_trypullbuf(d)) { - return false; + 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; + } } - *val = upb_decode_varint32(d); - return true; + return decode_v32_slow(d); } -FORCEINLINE uint64_t upb_decode_varint(upb_decoder *d) { - if (upb_decoder_bufleft(d) >= 10) { +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) upb_decoder_abortjmp(d, "Unterminated varint"); - upb_decoder_advance(d, r.p - d->ptr); + if (r.p == NULL) abortjmp(d, "Unterminated varint"); + advance(d, r.p - d->ptr); return r.val; - } else if (upb_decoder_bufleft(d) > 0) { - // Intermediate case -- worth it? - char tmpbuf[10]; - memset(tmpbuf, 0x80, 10); - memcpy(tmpbuf, d->ptr, upb_decoder_bufleft(d)); - upb_decoderet r = upb_vdecode_fast(tmpbuf); - if (r.p != NULL) { - upb_decoder_advance(d, r.p - tmpbuf); - return r.val; - } - } - // Slow case -- varint spans buffer seam. - return upb_decode_varint_slow(d); -} - -FORCEINLINE void upb_decode_fixed(upb_decoder *d, char *buf, size_t bytes) { - if (upb_decoder_bufleft(d) >= bytes) { - // Fast case. - memcpy(buf, d->ptr, bytes); - upb_decoder_advance(d, bytes); } else { - // Slow case. - size_t read = 0; - while (1) { - size_t avail = UPB_MIN(upb_decoder_bufleft(d), bytes - read); - memcpy(buf + read, d->ptr, avail); - upb_decoder_advance(d, avail); - read += avail; - if (read == bytes) break; - upb_pullbuf(d); - } + // Slow case -- varint spans buffer seam. + return decode_varint_slow(d); } } -FORCEINLINE uint32_t upb_decode_fixed32(upb_decoder *d) { +FORCEINLINE uint32_t decode_fixed32(upb_pbdecoder *d) { uint32_t u32; - upb_decode_fixed(d, (char*)&u32, sizeof(uint32_t)); + getbytes(d, &u32, 4); return u32; // TODO: proper byte swapping for big-endian machines. } -FORCEINLINE uint64_t upb_decode_fixed64(upb_decoder *d) { + +FORCEINLINE uint64_t decode_fixed64(upb_pbdecoder *d) { uint64_t u64; - upb_decode_fixed(d, (char*)&u64, sizeof(uint64_t)); + getbytes(d, &u64, 8); return u64; // TODO: proper byte swapping for big-endian machines. } -INLINE void upb_push_msg(upb_decoder *d, const upb_fielddef *f, uint64_t end) { - upb_decoder_frame *fr = d->top + 1; - if (!upb_sink_startsubmsg(&d->sink, f) || fr > d->limit) { - upb_decoder_abortjmp(d, "Nesting too deep."); - } +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 = false; - fr->is_packed = false; + fr->is_sequence = is_sequence; + fr->is_packed = is_packed; fr->end_ofs = end; - fr->group_fieldnum = end == UPB_NONDELIMITED ? - (int32_t)upb_fielddef_number(f) : -1; + fr->group_fieldnum = group_fieldnum; d->top = fr; - upb_decoder_setmsgend(d); + set_delim_end(d); } -INLINE void upb_push_seq(upb_decoder *d, const upb_fielddef *f, bool packed, - uint64_t end_ofs) { - upb_decoder_frame *fr = d->top + 1; - if (!upb_sink_startseq(&d->sink, f) || fr > d->limit) { - upb_decoder_abortjmp(d, "Nesting too deep."); - } - fr->f = f; - fr->is_sequence = true; - fr->group_fieldnum = -1; - fr->is_packed = packed; - fr->end_ofs = end_ofs; - d->top = fr; - upb_decoder_setmsgend(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); } -INLINE void upb_pop_submsg(upb_decoder *d) { - upb_sink_endsubmsg(&d->sink, d->top->f); +static void pop_submsg(upb_pbdecoder *d) { + upb_sink_endsubmsg(d->sink, getselector(d->top->f, UPB_HANDLER_ENDSUBMSG)); d->top--; - upb_decoder_setmsgend(d); + set_delim_end(d); } -INLINE void upb_pop_seq(upb_decoder *d) { - upb_sink_endseq(&d->sink, d->top->f); +static void pop_seq(upb_pbdecoder *d) { + upb_sink_endseq(d->sink, getselector(d->top->f, UPB_HANDLER_ENDSEQ)); d->top--; - upb_decoder_setmsgend(d); + 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); + } + } } @@ -374,95 +517,79 @@ INLINE void upb_pop_seq(upb_decoder *d) { // 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, wt, name, convfunc) \ - INLINE void upb_decode_ ## type(upb_decoder *d, const upb_fielddef *f) { \ - upb_sink_put ## name(&d->sink, f, (convfunc)(upb_decode_ ## wt(d))); \ +#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, varint, int32, int32_t) -T(INT64, varint, int64, int64_t) -T(UINT32, varint, uint32, uint32_t) -T(UINT64, varint, uint64, uint64_t) -T(FIXED32, fixed32, uint32, uint32_t) -T(FIXED64, fixed64, uint64, uint64_t) -T(SFIXED32, fixed32, int32, int32_t) -T(SFIXED64, fixed64, int64, int64_t) -T(BOOL, varint, bool, bool) -T(ENUM, varint, int32, int32_t) -T(DOUBLE, fixed64, double, upb_asdouble) -T(FLOAT, fixed32, float, upb_asfloat) -T(SINT32, varint, int32, upb_zzdec_32) -T(SINT64, varint, int64, upb_zzdec_64) +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 upb_decode_GROUP(upb_decoder *d, const upb_fielddef *f) { - upb_push_msg(d, f, UPB_NONDELIMITED); -} - -static void upb_decode_MESSAGE(upb_decoder *d, const upb_fielddef *f) { - uint32_t len = upb_decode_varint32(d); - upb_push_msg(d, f, upb_decoder_offset(d) + len); -} - -static void upb_decode_STRING(upb_decoder *d, const upb_fielddef *f) { - uint32_t strlen = upb_decode_varint32(d); - uint64_t offset = upb_decoder_offset(d); - uint64_t end = offset + strlen; - if (end > upb_byteregion_endofs(d->input)) - upb_decoder_abortjmp(d, "Unexpected EOF"); - upb_sink_startstr(&d->sink, f, strlen); - while (strlen > 0) { - if (upb_byteregion_available(d->input, offset) == 0) - upb_pullbuf(d); - size_t len; - const char *ptr = upb_byteregion_getptr(d->input, offset, &len); - len = UPB_MIN(len, strlen); - len = upb_sink_putstring(&d->sink, f, ptr, len); - if (len > strlen) - upb_decoder_abortjmp(d, "Skipped too many bytes."); - offset += len; - strlen -= len; - upb_decoder_discardto(d, offset); - } - upb_sink_endstr(&d->sink, f); +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); +} -/* The main decoding loop *****************************************************/ - -static void upb_decoder_checkdelim(upb_decoder *d) { - // TODO: This doesn't work for the case that no buffer is currently loaded - // (ie. d->buf == NULL) because delim_end is NULL even if we are at - // end-of-delim. Need to add a test that exercises this by putting a buffer - // seam in the middle of the final delimited value in a proto that we skip - // for some reason (like because it's unknown and we have no unknown field - // handler). - while (d->delim_end != NULL && d->ptr >= d->delim_end) { - if (d->ptr > d->delim_end) upb_decoder_abortjmp(d, "Bad submessage end"); - if (d->top->is_sequence) { - upb_pop_seq(d); - } else { - upb_pop_submsg(d); +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); } } -INLINE const upb_fielddef *upb_decode_tag(upb_decoder *d) { + +/* The main decoding loop *****************************************************/ + +static const upb_fielddef *decode_tag(upb_pbdecoder *d) { while (1) { - uint32_t tag; - if (!upb_trydecode_varint32(d, &tag)) return NULL; + 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_sink_tophandlers(&d->sink); + 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_fieldtype_t type = upb_fielddef_type(f); + 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 && @@ -477,18 +604,19 @@ INLINE const upb_fielddef *upb_decode_tag(upb_decoder *d) { // 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. - upb_decoder_frame *fr = d->top; + frame *fr = d->top; if (fr->is_sequence && fr->f != f) { - upb_pop_seq(d); + pop_seq(d); fr = d->top; } if (f && upb_fielddef_isseq(f) && !fr->is_sequence) { if (packed) { - uint32_t len = upb_decode_varint32(d); - upb_push_seq(d, f, true, upb_decoder_offset(d) + len); + uint32_t len = decode_v32(d); + push_seq(d, f, true, offset(d) + len); + checkpoint(d); } else { - upb_push_seq(d, f, false, fr->end_ofs); + push_seq(d, f, false, fr->end_ofs); } } @@ -496,118 +624,202 @@ INLINE const upb_fielddef *upb_decode_tag(upb_decoder *d) { // Unknown field or ENDGROUP. if (fieldnum == 0 || fieldnum > UPB_MAX_FIELDNUMBER) - upb_decoder_abortjmp(d, "Invalid field number"); + abortjmp(d, "Invalid field number"); switch (wire_type) { - case UPB_WIRE_TYPE_VARINT: upb_decode_varint(d); break; - case UPB_WIRE_TYPE_32BIT: upb_decoder_discard(d, 4); break; - case UPB_WIRE_TYPE_64BIT: upb_decoder_discard(d, 8); break; - case UPB_WIRE_TYPE_DELIMITED: - upb_decoder_discard(d, upb_decode_varint32(d)); break; + 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: - upb_decoder_abortjmp(d, "Can't handle unknown groups yet"); + abortjmp(d, "Can't handle unknown groups yet"); case UPB_WIRE_TYPE_END_GROUP: if (fieldnum != fr->group_fieldnum) - upb_decoder_abortjmp(d, "Unmatched ENDGROUP tag"); - upb_sink_endsubmsg(&d->sink, fr->f); - d->top--; - upb_decoder_setmsgend(d); + abortjmp(d, "Unmatched ENDGROUP tag"); + pop_submsg(d); break; default: - upb_decoder_abortjmp(d, "Invalid wire type"); + abortjmp(d, "Invalid wire type"); } // TODO: deliver to unknown field callback. - upb_decoder_checkpoint(d); - upb_decoder_checkdelim(d); + checkpoint(d); + checkdelim(d); } } -upb_success_t upb_decoder_decode(upb_decoder *d) { - assert(d->input); +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)) { - assert(!upb_ok(&d->status)); - return UPB_ERROR; + // 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; + } + } } - upb_sink_startmsg(&d->sink); - // Prime the buf so we can hit the JIT immediately. - upb_trypullbuf(d); + checkpoint(d); + const upb_fielddef *f = d->top->f; while(1) { #ifdef UPB_USE_JIT_X64 - upb_decoder_enterjit(d); - upb_decoder_checkpoint(d); - upb_decoder_setmsgend(d); + upb_decoder_enterjit(d, plan); + checkpoint(d); + set_delim_end(d); // JIT doesn't keep this current. #endif - upb_decoder_checkdelim(d); - if (!d->top_is_packed) f = upb_decode_tag(d); - if (!f) { - // Sucessful EOF. We may need to dispatch a top-level implicit frame. - if (d->top->is_sequence) { - assert(d->sink.top == d->sink.stack + 1); - upb_pop_seq(d); - } - assert(d->top == d->stack); - upb_sink_endmsg(&d->sink, &d->status); - return UPB_OK; + checkdelim(d); + if (!d->top->is_packed) { + f = decode_tag(d); } - switch (upb_fielddef_type(f)) { - case UPB_TYPE(DOUBLE): upb_decode_DOUBLE(d, f); break; - case UPB_TYPE(FLOAT): upb_decode_FLOAT(d, f); break; - case UPB_TYPE(INT64): upb_decode_INT64(d, f); break; - case UPB_TYPE(UINT64): upb_decode_UINT64(d, f); break; - case UPB_TYPE(INT32): upb_decode_INT32(d, f); break; - case UPB_TYPE(FIXED64): upb_decode_FIXED64(d, f); break; - case UPB_TYPE(FIXED32): upb_decode_FIXED32(d, f); break; - case UPB_TYPE(BOOL): upb_decode_BOOL(d, f); break; - case UPB_TYPE(STRING): - case UPB_TYPE(BYTES): upb_decode_STRING(d, f); break; - case UPB_TYPE(GROUP): upb_decode_GROUP(d, f); break; - case UPB_TYPE(MESSAGE): upb_decode_MESSAGE(d, f); break; - case UPB_TYPE(UINT32): upb_decode_UINT32(d, f); break; - case UPB_TYPE(ENUM): upb_decode_ENUM(d, f); break; - case UPB_TYPE(SFIXED32): upb_decode_SFIXED32(d, f); break; - case UPB_TYPE(SFIXED64): upb_decode_SFIXED64(d, f); break; - case UPB_TYPE(SINT32): upb_decode_SINT32(d, f); break; - case UPB_TYPE(SINT64): upb_decode_SINT64(d, f); break; - case UPB_TYPE_NONE: assert(false); break; + 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; } - upb_decoder_checkpoint(d); + checkpoint(d); } } -void upb_decoder_init(upb_decoder *d) { - upb_status_init(&d->status); - d->plan = NULL; - d->input = NULL; +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 upb_decoder_resetplan(upb_decoder *d, upb_decoderplan *p) { - d->plan = p; - d->input = NULL; - upb_sink_init(&d->sink, p->handlers); -} - -void upb_decoder_resetinput(upb_decoder *d, upb_byteregion *input, - void *c) { - assert(d->plan); - upb_status_clear(&d->status); - upb_sink_reset(&d->sink, c); - d->input = input; - +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; - - // Protect against assert in skiptonewbuf(). d->bufstart_ofs = 0; - d->ptr = NULL; - d->buf = NULL; - upb_decoder_skiptonewbuf(d, upb_byteregion_startofs(input)); + d->ptr = d->residual; + d->buf = d->residual; + d->end = d->residual; + d->residual_end = d->residual; } -void upb_decoder_uninit(upb_decoder *d) { - upb_status_uninit(&d->status); +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; } |