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cobalt / cobalt / 175e9c896d40cc39319fd3595f921d451f1e13aa / . / src / third_party / protobuf-3 / src / google / protobuf / stubs / structurally_valid.cc
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// Copyright 2005-2008 Google Inc. All Rights Reserved.
// Author: jrm@google.com (Jim Meehan)
#include <google/protobuf/stubs/common.h>
#include <google/protobuf/stubs/stringpiece.h>
namespace google {
namespace protobuf {
namespace internal {
// These four-byte entries compactly encode how many bytes 0..255 to delete
// in making a string replacement, how many bytes to add 0..255, and the offset
// 0..64k-1 of the replacement string in remap_string.
struct RemapEntry {
uint8 delete_bytes;
uint8 add_bytes;
uint16 bytes_offset;
};
// Exit type codes for state tables. All but the first get stuffed into
// signed one-byte entries. The first is only generated by executable code.
// To distinguish from next-state entries, these must be contiguous and
// all <= kExitNone
typedef enum {
kExitDstSpaceFull = 239,
kExitIllegalStructure, // 240
kExitOK, // 241
kExitReject, // ...
kExitReplace1,
kExitReplace2,
kExitReplace3,
kExitReplace21,
kExitReplace31,
kExitReplace32,
kExitReplaceOffset1,
kExitReplaceOffset2,
kExitReplace1S0,
kExitSpecial,
kExitDoAgain,
kExitRejectAlt,
kExitNone // 255
} ExitReason;
// This struct represents one entire state table. The three initialized byte
// areas are state_table, remap_base, and remap_string. state0 and state0_size
// give the byte offset and length within state_table of the initial state --
// table lookups are expected to start and end in this state, but for
// truncated UTF-8 strings, may end in a different state. These allow a quick
// test for that condition. entry_shift is 8 for tables subscripted by a full
// byte value and 6 for space-optimized tables subscripted by only six
// significant bits in UTF-8 continuation bytes.
typedef struct {
const uint32 state0;
const uint32 state0_size;
const uint32 total_size;
const int max_expand;
const int entry_shift;
const int bytes_per_entry;
const uint32 losub;
const uint32 hiadd;
const uint8* state_table;
const RemapEntry* remap_base;
const uint8* remap_string;
const uint8* fast_state;
} UTF8StateMachineObj;
typedef UTF8StateMachineObj UTF8ScanObj;
#define X__ (kExitIllegalStructure)
#define RJ_ (kExitReject)
#define S1_ (kExitReplace1)
#define S2_ (kExitReplace2)
#define S3_ (kExitReplace3)
#define S21 (kExitReplace21)
#define S31 (kExitReplace31)
#define S32 (kExitReplace32)
#define T1_ (kExitReplaceOffset1)
#define T2_ (kExitReplaceOffset2)
#define S11 (kExitReplace1S0)
#define SP_ (kExitSpecial)
#define D__ (kExitDoAgain)
#define RJA (kExitRejectAlt)
// Entire table has 9 state blocks of 256 entries each
static const unsigned int utf8acceptnonsurrogates_STATE0 = 0; // state[0]
static const unsigned int utf8acceptnonsurrogates_STATE0_SIZE = 256; // =[1]
static const unsigned int utf8acceptnonsurrogates_TOTAL_SIZE = 2304;
static const unsigned int utf8acceptnonsurrogates_MAX_EXPAND_X4 = 0;
static const unsigned int utf8acceptnonsurrogates_SHIFT = 8;
static const unsigned int utf8acceptnonsurrogates_BYTES = 1;
static const unsigned int utf8acceptnonsurrogates_LOSUB = 0x20202020;
static const unsigned int utf8acceptnonsurrogates_HIADD = 0x00000000;
static const uint8 utf8acceptnonsurrogates[] = {
// state[0] 0x000000 Byte 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,
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,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, 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,
2, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 7, 3, 3,
4, 5, 5, 5, 6, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
// state[1] 0x000080 Byte 2 of 2
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
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,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
// state[2] 0x000000 Byte 2 of 3
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
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,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
// state[3] 0x001000 Byte 2 of 3
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
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,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
// state[4] 0x000000 Byte 2 of 4
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
// state[5] 0x040000 Byte 2 of 4
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
// state[6] 0x100000 Byte 2 of 4
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
// state[7] 0x00d000 Byte 2 of 3
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
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,
8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
// state[8] 0x00d800 Byte 3 of 3
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
RJ_, RJ_, RJ_, RJ_, RJ_, RJ_, RJ_, RJ_, RJ_, RJ_, RJ_, RJ_, RJ_, RJ_, RJ_, RJ_,
RJ_, RJ_, RJ_, RJ_, RJ_, RJ_, RJ_, RJ_, RJ_, RJ_, RJ_, RJ_, RJ_, RJ_, RJ_, RJ_,
RJ_, RJ_, RJ_, RJ_, RJ_, RJ_, RJ_, RJ_, RJ_, RJ_, RJ_, RJ_, RJ_, RJ_, RJ_, RJ_,
RJ_, RJ_, RJ_, RJ_, RJ_, RJ_, RJ_, RJ_, RJ_, RJ_, RJ_, RJ_, RJ_, RJ_, RJ_, RJ_,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__, X__,
};
// Remap base[0] = (del, add, string_offset)
static const RemapEntry utf8acceptnonsurrogates_remap_base[] = {
{0, 0, 0} };
// Remap string[0]
static const unsigned char utf8acceptnonsurrogates_remap_string[] = {
0 };
static const unsigned char utf8acceptnonsurrogates_fast[256] = {
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,
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,
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,
};
static const UTF8ScanObj utf8acceptnonsurrogates_obj = {
utf8acceptnonsurrogates_STATE0,
utf8acceptnonsurrogates_STATE0_SIZE,
utf8acceptnonsurrogates_TOTAL_SIZE,
utf8acceptnonsurrogates_MAX_EXPAND_X4,
utf8acceptnonsurrogates_SHIFT,
utf8acceptnonsurrogates_BYTES,
utf8acceptnonsurrogates_LOSUB,
utf8acceptnonsurrogates_HIADD,
utf8acceptnonsurrogates,
utf8acceptnonsurrogates_remap_base,
utf8acceptnonsurrogates_remap_string,
utf8acceptnonsurrogates_fast
};
#undef X__
#undef RJ_
#undef S1_
#undef S2_
#undef S3_
#undef S21
#undef S31
#undef S32
#undef T1_
#undef T2_
#undef S11
#undef SP_
#undef D__
#undef RJA
// Return true if current Tbl pointer is within state0 range
// Note that unsigned compare checks both ends of range simultaneously
static inline bool InStateZero(const UTF8ScanObj* st, const uint8* Tbl) {
const uint8* Tbl0 = &st->state_table[st->state0];
return (static_cast<uint32>(Tbl - Tbl0) < st->state0_size);
}
// Scan a UTF-8 string based on state table.
// Always scan complete UTF-8 characters
// Set number of bytes scanned. Return reason for exiting
int UTF8GenericScan(const UTF8ScanObj* st,
const char * str,
int str_length,
int* bytes_consumed) {
*bytes_consumed = 0;
if (str_length == 0) return kExitOK;
int eshift = st->entry_shift;
const uint8* isrc = reinterpret_cast<const uint8*>(str);
const uint8* src = isrc;
const uint8* srclimit = isrc + str_length;
const uint8* srclimit8 = srclimit - 7;
const uint8* Tbl_0 = &st->state_table[st->state0];
DoAgain:
// Do state-table scan
int e = 0;
uint8 c;
const uint8* Tbl2 = &st->fast_state[0];
const uint32 losub = st->losub;
const uint32 hiadd = st->hiadd;
// Check initial few bytes one at a time until 8-byte aligned
//----------------------------
while ((((uintptr_t)src & 0x07) != 0) &&
(src < srclimit) &&
Tbl2[src[0]] == 0) {
src++;
}
if (((uintptr_t)src & 0x07) == 0) {
// Do fast for groups of 8 identity bytes.
// This covers a lot of 7-bit ASCII ~8x faster then the 1-byte loop,
// including slowing slightly on cr/lf/ht
//----------------------------
while (src < srclimit8) {
uint32 s0123 = (reinterpret_cast<const uint32 *>(src))[0];
uint32 s4567 = (reinterpret_cast<const uint32 *>(src))[1];
src += 8;
// This is a fast range check for all bytes in [lowsub..0x80-hiadd)
uint32 temp = (s0123 - losub) | (s0123 + hiadd) |
(s4567 - losub) | (s4567 + hiadd);
if ((temp & 0x80808080) != 0) {
// We typically end up here on cr/lf/ht; src was incremented
int e0123 = (Tbl2[src[-8]] | Tbl2[src[-7]]) |
(Tbl2[src[-6]] | Tbl2[src[-5]]);
if (e0123 != 0) {
src -= 8;
break;
} // Exit on Non-interchange
e0123 = (Tbl2[src[-4]] | Tbl2[src[-3]]) |
(Tbl2[src[-2]] | Tbl2[src[-1]]);
if (e0123 != 0) {
src -= 4;
break;
} // Exit on Non-interchange
// Else OK, go around again
}
}
}
//----------------------------
// Byte-at-a-time scan
//----------------------------
const uint8* Tbl = Tbl_0;
while (src < srclimit) {
c = *src;
e = Tbl[c];
src++;
if (e >= kExitIllegalStructure) {break;}
Tbl = &Tbl_0[e << eshift];
}
//----------------------------
// Exit posibilities:
// Some exit code, !state0, back up over last char
// Some exit code, state0, back up one byte exactly
// source consumed, !state0, back up over partial char
// source consumed, state0, exit OK
// For illegal byte in state0, avoid backup up over PREVIOUS char
// For truncated last char, back up to beginning of it
if (e >= kExitIllegalStructure) {
// Back up over exactly one byte of rejected/illegal UTF-8 character
src--;
// Back up more if needed
if (!InStateZero(st, Tbl)) {
do {
src--;
} while ((src > isrc) && ((src[0] & 0xc0) == 0x80));
}
} else if (!InStateZero(st, Tbl)) {
// Back up over truncated UTF-8 character
e = kExitIllegalStructure;
do {
src--;
} while ((src > isrc) && ((src[0] & 0xc0) == 0x80));
} else {
// Normal termination, source fully consumed
e = kExitOK;
}
if (e == kExitDoAgain) {
// Loop back up to the fast scan
goto DoAgain;
}
*bytes_consumed = src - isrc;
return e;
}
int UTF8GenericScanFastAscii(const UTF8ScanObj* st,
const char * str,
int str_length,
int* bytes_consumed) {
*bytes_consumed = 0;
if (str_length == 0) return kExitOK;
const uint8* isrc = reinterpret_cast<const uint8*>(str);
const uint8* src = isrc;
const uint8* srclimit = isrc + str_length;
const uint8* srclimit8 = srclimit - 7;
int n;
int rest_consumed;
int exit_reason;
do {
// Check initial few bytes one at a time until 8-byte aligned
while ((((uintptr_t)src & 0x07) != 0) &&
(src < srclimit) && (src[0] < 0x80)) {
src++;
}
if (((uintptr_t)src & 0x07) == 0) {
while ((src < srclimit8) &&
(((reinterpret_cast<const uint32*>(src)[0] |
reinterpret_cast<const uint32*>(src)[1]) & 0x80808080) == 0)) {
src += 8;
}
}
while ((src < srclimit) && (src[0] < 0x80)) {
src++;
}
// Run state table on the rest
n = src - isrc;
exit_reason = UTF8GenericScan(st, str + n, str_length - n, &rest_consumed);
src += rest_consumed;
} while ( exit_reason == kExitDoAgain );
*bytes_consumed = src - isrc;
return exit_reason;
}
// Hack: On some compilers the static tables are initialized at startup.
// We can't use them until they are initialized. However, some Protocol
// Buffer parsing happens at static init time and may try to validate
// UTF-8 strings. Since UTF-8 validation is only used for debugging
// anyway, we simply always return success if initialization hasn't
// occurred yet.
namespace {
bool module_initialized_ = false;
struct InitDetector {
InitDetector() {
module_initialized_ = true;
}
};
InitDetector init_detector;
} // namespace
bool IsStructurallyValidUTF8(const char* buf, int len) {
if (!module_initialized_) return true;
int bytes_consumed = 0;
UTF8GenericScanFastAscii(&utf8acceptnonsurrogates_obj,
buf, len, &bytes_consumed);
return (bytes_consumed == len);
}
int UTF8SpnStructurallyValid(const StringPiece& str) {
if (!module_initialized_) return str.size();
int bytes_consumed = 0;
UTF8GenericScanFastAscii(&utf8acceptnonsurrogates_obj,
str.data(), str.size(), &bytes_consumed);
return bytes_consumed;
}
// Coerce UTF-8 byte string in src_str to be
// a structurally-valid equal-length string by selectively
// overwriting illegal bytes with replace_char (typically blank).
// replace_char must be legal printable 7-bit Ascii 0x20..0x7e.
// src_str is read-only. If any overwriting is needed, a modified byte string
// is created in idst, length isrclen.
//
// Returns pointer to output buffer, isrc if no changes were made,
// or idst if some bytes were changed.
//
// Fast case: all is structurally valid and no byte copying is done.
//
char* UTF8CoerceToStructurallyValid(const StringPiece& src_str,
char* idst,
const char replace_char) {
const char* isrc = src_str.data();
const int len = src_str.length();
int n = UTF8SpnStructurallyValid(src_str);
if (n == len) { // Normal case -- all is cool, return
return const_cast<char*>(isrc);
} else { // Unusual case -- copy w/o bad bytes
const char* src = isrc;
const char* srclimit = isrc + len;
char* dst = idst;
memmove(dst, src, n); // Copy initial good chunk
src += n;
dst += n;
while (src < srclimit) { // src points to bogus byte or is off the end
dst[0] = replace_char; // replace one bad byte
src++;
dst++;
StringPiece str2(src, srclimit - src);
n = UTF8SpnStructurallyValid(str2); // scan the remainder
memmove(dst, src, n); // copy next good chunk
src += n;
dst += n;
}
}
return idst;
}
} // namespace internal
} // namespace protobuf
} // namespace google