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Int64 file map serialization [skip ci]

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This commit is contained in:
Ali 2022-05-10 18:03:59 +04:00
parent 72923655e4
commit f3b744c0d9
1 changed files with 130 additions and 58 deletions
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188
submodules/Postbox/Sources/MediaBoxFile.swift
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@ -21,74 +21,146 @@ private final class MediaBoxFileMap {
return nil
}
var crc: UInt32 = 0
var count: Int32 = 0
var sum: Int32 = 0
var ranges: IndexSet = IndexSet()
guard fd.read(&crc, 4) == 4 else {
return nil
}
guard fd.read(&count, 4) == 4 else {
var firstUInt32: UInt32 = 0
guard fd.read(&firstUInt32, 4) == 4 else {
return nil
}
if count < 0 {
return nil
}
if count < 0 || length < 4 + 4 + count * 2 * 4 {
return nil
}
var truncationSizeValue: Int32 = 0
var data = Data(count: Int(4 + count * 2 * 4))
let dataCount = data.count
if !(data.withUnsafeMutableBytes { rawBytes -> Bool in
let bytes = rawBytes.baseAddress!.assumingMemoryBound(to: UInt8.self)
if firstUInt32 == 0x7bac1487 {
var crc: UInt32 = 0
guard fd.read(&crc, 4) == 4 else {
return nil
}
var count: Int32 = 0
var sum: Int64 = 0
var ranges: IndexSet = IndexSet()
guard fd.read(&count, 4) == 4 else {
return nil
}
if count < 0 {
return nil
}
if count < 0 || length < 4 + 4 + 8 + count * 2 * 8 {
return nil
}
var truncationSizeValue: Int32 = 0
var data = Data(count: Int(8 + count * 2 * 8))
let dataCount = data.count
if !(data.withUnsafeMutableBytes { rawBytes -> Bool in
let bytes = rawBytes.baseAddress!.assumingMemoryBound(to: UInt8.self)
guard fd.read(bytes, dataCount) == dataCount else {
return false
}
memcpy(&truncationSizeValue, bytes, 4)
let calculatedCrc = Crc32(bytes, Int32(dataCount))
if calculatedCrc != crc {
return false
}
var offset = 4
for _ in 0 ..< count {
var intervalOffset: Int32 = 0
var intervalLength: Int32 = 0
memcpy(&intervalOffset, bytes.advanced(by: offset), 4)
memcpy(&intervalLength, bytes.advanced(by: offset + 4), 4)
offset += 8
guard fd.read(bytes, dataCount) == dataCount else {
return false
}
ranges.insert(integersIn: Int(intervalOffset) ..< Int(intervalOffset + intervalLength))
memcpy(&truncationSizeValue, bytes, 8)
sum += intervalLength
let calculatedCrc = Crc32(bytes, Int32(dataCount))
if calculatedCrc != crc {
return false
}
var offset = 8
for _ in 0 ..< count {
var intervalOffset: Int64 = 0
var intervalLength: Int64 = 0
memcpy(&intervalOffset, bytes.advanced(by: offset), 8)
memcpy(&intervalLength, bytes.advanced(by: offset + 8), 8)
offset += 8 * 2
ranges.insert(integersIn: Int(intervalOffset) ..< Int(intervalOffset + intervalLength))
sum += intervalLength
}
return true
}) {
return nil
}
return true
}) {
return nil
}
self.sum = Int64(sum)
self.ranges = ranges
if truncationSizeValue == -1 {
self.truncationSize = nil
self.sum = sum
self.ranges = ranges
if truncationSizeValue == -1 {
self.truncationSize = nil
} else {
self.truncationSize = Int64(truncationSizeValue)
}
} else {
self.truncationSize = Int64(truncationSizeValue)
let crc: UInt32 = firstUInt32
var count: Int32 = 0
var sum: Int32 = 0
var ranges: IndexSet = IndexSet()
guard fd.read(&count, 4) == 4 else {
return nil
}
if count < 0 {
return nil
}
if count < 0 || length < 4 + 4 + count * 2 * 4 {
return nil
}
var truncationSizeValue: Int32 = 0
var data = Data(count: Int(4 + count * 2 * 4))
let dataCount = data.count
if !(data.withUnsafeMutableBytes { rawBytes -> Bool in
let bytes = rawBytes.baseAddress!.assumingMemoryBound(to: UInt8.self)
guard fd.read(bytes, dataCount) == dataCount else {
return false
}
memcpy(&truncationSizeValue, bytes, 4)
let calculatedCrc = Crc32(bytes, Int32(dataCount))
if calculatedCrc != crc {
return false
}
var offset = 4
for _ in 0 ..< count {
var intervalOffset: Int32 = 0
var intervalLength: Int32 = 0
memcpy(&intervalOffset, bytes.advanced(by: offset), 4)
memcpy(&intervalLength, bytes.advanced(by: offset + 4), 4)
offset += 8
ranges.insert(integersIn: Int(intervalOffset) ..< Int(intervalOffset + intervalLength))
sum += intervalLength
}
return true
}) {
return nil
}
self.sum = Int64(sum)
self.ranges = ranges
if truncationSizeValue == -1 {
self.truncationSize = nil
} else {
self.truncationSize = Int64(truncationSizeValue)
}
}
}
func serialize(to file: ManagedFile) {
file.seek(position: 0)
let buffer = WriteBuffer()
var magic: UInt32 = 0x7bac1487
buffer.write(&magic, offset: 0, length: 4)
var zero: Int32 = 0
buffer.write(&zero, offset: 0, length: 4)
@ -96,16 +168,16 @@ private final class MediaBoxFileMap {
var count: Int32 = Int32(rangeView.count)
buffer.write(&count, offset: 0, length: 4)
var truncationSizeValue: Int32 = Int32(self.truncationSize ?? -1)
buffer.write(&truncationSizeValue, offset: 0, length: 4)
var truncationSizeValue: Int64 = self.truncationSize ?? -1
buffer.write(&truncationSizeValue, offset: 0, length: 8)
for range in rangeView {
var intervalOffset = Int32(range.lowerBound)
var intervalLength = Int32(range.count)
buffer.write(&intervalOffset, offset: 0, length: 4)
buffer.write(&intervalLength, offset: 0, length: 4)
buffer.write(&intervalOffset, offset: 0, length: 8)
buffer.write(&intervalLength, offset: 0, length: 8)
}
var crc: UInt32 = Crc32(buffer.memory.advanced(by: 4 * 2), Int32(buffer.length - 4 * 2))
var crc: UInt32 = Crc32(buffer.memory.advanced(by: 4 + 4 + 4), Int32(buffer.length - (4 + 4 + 4)))
memcpy(buffer.memory, &crc, 4)
let written = file.write(buffer.memory, count: buffer.length)
assert(written == buffer.length)