blob: a7a60f2ef2971018934267d14e6150a7482c0072 [file] [log] [blame]
// Protocol Buffers - Google's data interchange format
// Copyright 2023 Google LLC. All rights reserved.
//
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file or at
// https://developers.google.com/open-source/licenses/bsd
#include "upb/message/internal/compare_unknown.h"
#include <stdlib.h>
#include "upb/base/string_view.h"
#include "upb/mem/alloc.h"
#include "upb/wire/eps_copy_input_stream.h"
#include "upb/wire/reader.h"
#include "upb/wire/types.h"
// Must be last.
#include "upb/port/def.inc"
typedef struct upb_UnknownFields upb_UnknownFields;
typedef struct {
uint32_t tag;
union {
uint64_t varint;
uint64_t uint64;
uint32_t uint32;
upb_StringView delimited;
upb_UnknownFields* group;
} data;
} upb_UnknownField;
struct upb_UnknownFields {
size_t size;
size_t capacity;
upb_UnknownField* fields;
};
typedef struct {
upb_EpsCopyInputStream stream;
upb_Arena* arena;
upb_UnknownField* tmp;
size_t tmp_size;
int depth;
upb_UnknownCompareResult status;
jmp_buf err;
} upb_UnknownField_Context;
UPB_NORETURN static void upb_UnknownFields_OutOfMemory(
upb_UnknownField_Context* ctx) {
ctx->status = kUpb_UnknownCompareResult_OutOfMemory;
UPB_LONGJMP(ctx->err, 1);
}
static void upb_UnknownFields_Grow(upb_UnknownField_Context* ctx,
upb_UnknownField** base,
upb_UnknownField** ptr,
upb_UnknownField** end) {
size_t old = (*ptr - *base);
size_t new = UPB_MAX(4, old * 2);
*base = upb_Arena_Realloc(ctx->arena, *base, old * sizeof(**base),
new * sizeof(**base));
if (!*base) upb_UnknownFields_OutOfMemory(ctx);
*ptr = *base + old;
*end = *base + new;
}
// We have to implement our own sort here, since qsort() is not an in-order
// sort. Here we use merge sort, the simplest in-order sort.
static void upb_UnknownFields_Merge(upb_UnknownField* arr, size_t start,
size_t mid, size_t end,
upb_UnknownField* tmp) {
memcpy(tmp, &arr[start], (end - start) * sizeof(*tmp));
upb_UnknownField* ptr1 = tmp;
upb_UnknownField* end1 = &tmp[mid - start];
upb_UnknownField* ptr2 = &tmp[mid - start];
upb_UnknownField* end2 = &tmp[end - start];
upb_UnknownField* out = &arr[start];
while (ptr1 < end1 && ptr2 < end2) {
if (ptr1->tag <= ptr2->tag) {
*out++ = *ptr1++;
} else {
*out++ = *ptr2++;
}
}
if (ptr1 < end1) {
memcpy(out, ptr1, (end1 - ptr1) * sizeof(*out));
} else if (ptr2 < end2) {
memcpy(out, ptr1, (end2 - ptr2) * sizeof(*out));
}
}
static void upb_UnknownFields_SortRecursive(upb_UnknownField* arr, size_t start,
size_t end, upb_UnknownField* tmp) {
if (end - start > 1) {
size_t mid = start + ((end - start) / 2);
upb_UnknownFields_SortRecursive(arr, start, mid, tmp);
upb_UnknownFields_SortRecursive(arr, mid, end, tmp);
upb_UnknownFields_Merge(arr, start, mid, end, tmp);
}
}
static void upb_UnknownFields_Sort(upb_UnknownField_Context* ctx,
upb_UnknownFields* fields) {
if (ctx->tmp_size < fields->size) {
const int oldsize = ctx->tmp_size * sizeof(*ctx->tmp);
ctx->tmp_size = UPB_MAX(8, ctx->tmp_size);
while (ctx->tmp_size < fields->size) ctx->tmp_size *= 2;
const int newsize = ctx->tmp_size * sizeof(*ctx->tmp);
ctx->tmp = upb_grealloc(ctx->tmp, oldsize, newsize);
}
upb_UnknownFields_SortRecursive(fields->fields, 0, fields->size, ctx->tmp);
}
static upb_UnknownFields* upb_UnknownFields_DoBuild(
upb_UnknownField_Context* ctx, const char** buf) {
upb_UnknownField* arr_base = NULL;
upb_UnknownField* arr_ptr = NULL;
upb_UnknownField* arr_end = NULL;
const char* ptr = *buf;
uint32_t last_tag = 0;
bool sorted = true;
while (!upb_EpsCopyInputStream_IsDone(&ctx->stream, &ptr)) {
uint32_t tag;
ptr = upb_WireReader_ReadTag(ptr, &tag);
UPB_ASSERT(tag <= UINT32_MAX);
int wire_type = upb_WireReader_GetWireType(tag);
if (wire_type == kUpb_WireType_EndGroup) break;
if (tag < last_tag) sorted = false;
last_tag = tag;
if (arr_ptr == arr_end) {
upb_UnknownFields_Grow(ctx, &arr_base, &arr_ptr, &arr_end);
}
upb_UnknownField* field = arr_ptr;
field->tag = tag;
arr_ptr++;
switch (wire_type) {
case kUpb_WireType_Varint:
ptr = upb_WireReader_ReadVarint(ptr, &field->data.varint);
break;
case kUpb_WireType_64Bit:
ptr = upb_WireReader_ReadFixed64(ptr, &field->data.uint64);
break;
case kUpb_WireType_32Bit:
ptr = upb_WireReader_ReadFixed32(ptr, &field->data.uint32);
break;
case kUpb_WireType_Delimited: {
int size;
ptr = upb_WireReader_ReadSize(ptr, &size);
const char* s_ptr = ptr;
ptr = upb_EpsCopyInputStream_ReadStringAliased(&ctx->stream, &s_ptr,
size);
field->data.delimited.data = s_ptr;
field->data.delimited.size = size;
break;
}
case kUpb_WireType_StartGroup:
if (--ctx->depth == 0) {
ctx->status = kUpb_UnknownCompareResult_MaxDepthExceeded;
UPB_LONGJMP(ctx->err, 1);
}
field->data.group = upb_UnknownFields_DoBuild(ctx, &ptr);
ctx->depth++;
break;
default:
UPB_UNREACHABLE();
}
}
*buf = ptr;
upb_UnknownFields* ret = upb_Arena_Malloc(ctx->arena, sizeof(*ret));
if (!ret) upb_UnknownFields_OutOfMemory(ctx);
ret->fields = arr_base;
ret->size = arr_ptr - arr_base;
ret->capacity = arr_end - arr_base;
if (!sorted) {
upb_UnknownFields_Sort(ctx, ret);
}
return ret;
}
// Builds a upb_UnknownFields data structure from the binary data in buf.
static upb_UnknownFields* upb_UnknownFields_Build(upb_UnknownField_Context* ctx,
const char* ptr,
size_t size) {
upb_EpsCopyInputStream_Init(&ctx->stream, &ptr, size, true);
upb_UnknownFields* fields = upb_UnknownFields_DoBuild(ctx, &ptr);
UPB_ASSERT(upb_EpsCopyInputStream_IsDone(&ctx->stream, &ptr) &&
!upb_EpsCopyInputStream_IsError(&ctx->stream));
return fields;
}
// Compares two sorted upb_UnknownFields structures for equality.
static bool upb_UnknownFields_IsEqual(const upb_UnknownFields* uf1,
const upb_UnknownFields* uf2) {
if (uf1->size != uf2->size) return false;
for (size_t i = 0, n = uf1->size; i < n; i++) {
upb_UnknownField* f1 = &uf1->fields[i];
upb_UnknownField* f2 = &uf2->fields[i];
if (f1->tag != f2->tag) return false;
int wire_type = f1->tag & 7;
switch (wire_type) {
case kUpb_WireType_Varint:
if (f1->data.varint != f2->data.varint) return false;
break;
case kUpb_WireType_64Bit:
if (f1->data.uint64 != f2->data.uint64) return false;
break;
case kUpb_WireType_32Bit:
if (f1->data.uint32 != f2->data.uint32) return false;
break;
case kUpb_WireType_Delimited:
if (!upb_StringView_IsEqual(f1->data.delimited, f2->data.delimited)) {
return false;
}
break;
case kUpb_WireType_StartGroup:
if (!upb_UnknownFields_IsEqual(f1->data.group, f2->data.group)) {
return false;
}
break;
default:
UPB_UNREACHABLE();
}
}
return true;
}
static upb_UnknownCompareResult upb_UnknownField_DoCompare(
upb_UnknownField_Context* ctx, const char* buf1, size_t size1,
const char* buf2, size_t size2) {
upb_UnknownCompareResult ret;
// First build both unknown fields into a sorted data structure (similar
// to the UnknownFieldSet in C++).
upb_UnknownFields* uf1 = upb_UnknownFields_Build(ctx, buf1, size1);
upb_UnknownFields* uf2 = upb_UnknownFields_Build(ctx, buf2, size2);
// Now perform the equality check on the sorted structures.
if (upb_UnknownFields_IsEqual(uf1, uf2)) {
ret = kUpb_UnknownCompareResult_Equal;
} else {
ret = kUpb_UnknownCompareResult_NotEqual;
}
return ret;
}
static upb_UnknownCompareResult upb_UnknownField_Compare(
upb_UnknownField_Context* const ctx, const char* const buf1,
const size_t size1, const char* const buf2, const size_t size2) {
upb_UnknownCompareResult ret;
if (UPB_SETJMP(ctx->err) == 0) {
ret = upb_UnknownField_DoCompare(ctx, buf1, size1, buf2, size2);
} else {
ret = ctx->status;
UPB_ASSERT(ret != kUpb_UnknownCompareResult_Equal);
}
upb_Arena_Free(ctx->arena);
upb_gfree(ctx->tmp);
return ret;
}
upb_UnknownCompareResult UPB_PRIVATE(_upb_Message_UnknownFieldsAreEqual)(
const char* buf1, size_t size1, const char* buf2, size_t size2,
int max_depth) {
if (size1 == 0 && size2 == 0) return kUpb_UnknownCompareResult_Equal;
if (size1 == 0 || size2 == 0) return kUpb_UnknownCompareResult_NotEqual;
if (memcmp(buf1, buf2, size1) == 0) return kUpb_UnknownCompareResult_Equal;
upb_UnknownField_Context ctx = {
.arena = upb_Arena_New(),
.depth = max_depth,
.tmp = NULL,
.tmp_size = 0,
.status = kUpb_UnknownCompareResult_Equal,
};
if (!ctx.arena) return kUpb_UnknownCompareResult_OutOfMemory;
return upb_UnknownField_Compare(&ctx, buf1, size1, buf2, size2);
}