From ba50ef22e3de777e6da86ec60582dd3b7844479a Mon Sep 17 00:00:00 2001
From: yizhi <946185759@qq.com>
Date: Wed, 6 Apr 2022 13:53:09 +0800
Subject: [PATCH] =?UTF-8?q?=E4=BF=AE=E5=A4=8D=E6=8D=A2=E8=A1=8C=E9=97=AE?=
 =?UTF-8?q?=E9=A2=98?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 package.json  |  2 +-
 src/reader.ts | 52 +++++++++++++++------------------------------------
 2 files changed, 16 insertions(+), 38 deletions(-)

diff --git a/package.json b/package.json
index 9e29a64..c3c5561 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "yizhi-multipart-reader",
-  "version": "1.0.2",
+  "version": "1.0.3",
   "description": "",
   "main": "dist/index.js",
   "types": "typing/index.d.ts",
diff --git a/src/reader.ts b/src/reader.ts
index 04bf468..9f01598 100644
--- a/src/reader.ts
+++ b/src/reader.ts
@@ -181,23 +181,12 @@ export class MultipartReader {
 		if (this.#boundary.compare(data, 0, this.#boundary.length) == 0) data = data.slice(this.#boundary.length)
 		else throw new Error('multipart body error')
 		//去除\r\n
-		if (data[0] == 13) {
-			data = data.slice(1)
-			if (data[0] == 10) data = data.slice(1)				// \r
-			else throw new Error('multipart body error')		// \r后面必须时\n
-		}
-		//去除\n
-		else if (data[0] == 10) data = data.slice(1)
-		//遇到 -- ， 可能就要结束了
-		else if (data[0] == 45 && data[1] == 45) {
-			//看看是否有换行，有换行表示结束
-			if (data[2] == 10 || (data[2] == 13 && data[3] == 10)) {
-				this.#saveHeader()
-				this.#state = ReadState.finish
-				return { left: null, exit: true }
-			}
-			//否则就当出错
-			else throw new Error('multipart body error')
+		if (data[0] == 13 && data[1] == 10) data = data.slice(2)
+		//遇到 --\r\n，表示读取完毕
+		else if (data[0] == 45 && data[1] == 45 && data[2] == 13 && data[3] == 10) {
+			this.#saveHeader()
+			this.#state = ReadState.finish
+			return { left: null, exit: true }
 		}
 		//上面的情况都不是，表示出错了
 		else throw new Error('multipart body error')
@@ -213,26 +202,20 @@ export class MultipartReader {
 		let endAt = 0
 		for (let i = 0; i < data.length; ++i) {
 			// 检测是不是两个连续换行
-			if (data[i] == 10) {
-				if (data[i + 1] == 10) {
-					endAt = i + 1
-					break
-				}
-				else if (data[i + 1] == 13 && data[i + 2] == 10) {
-					endAt = i + 2
-					break
-				}
+			if (data[i] == 13 && data[i + 1] == 10 && data[i + 2] == 13 && data[i + 3] == 10) {
+				endAt = i + 4
+				break
 			}
 		}
 		//如果头读取完成，则读取body
 		if (endAt) {
 			//取得头
-			const header = this.#headBuffer ? Buffer.concat([this.#headBuffer, data.slice(0, endAt + 1)]) : data.slice(0, endAt + 1)
+			const header = this.#headBuffer ? Buffer.concat([this.#headBuffer, data.slice(0, endAt)]) : data.slice(0, endAt)
 			this.#headBuffer = null
 			await this.#resolveHead((header + '').trim())
 			//读取内容
 			this.#state = ReadState.content
-			return { left: data.slice(endAt + 1), exit: false }
+			return { left: data.slice(endAt), exit: false }
 		}
 		//否则将内容缓存起来，下次处理
 		else {
@@ -244,15 +227,10 @@ export class MultipartReader {
 	//读取内容（头读取完后，就要读取内容了）
 	async #readContent(data: Buffer): Promise<IReadResult> {
 		for (let i = 0; i < data.length; ++i) {
-			//处理换行
-			let gotbr = 0
-			if (data[i] == 10) gotbr = 1
-			else if (data[i] == 13 && data[i + 1] == 10) gotbr = 2
-
 			//遇到换行，那么很有可能就遇到了分隔符
-			if (gotbr) {
+			if (data[i] == 13 && data[i + 1] == 10) {
 				//看看内容够不够，不够啦？先保存起来，剩下的下次处理
-				if (data.length - i - gotbr - 2 < this.#boundary.length) {			//-gotbr表示减去换行符，-2表示减去分隔符开始的--
+				if (data.length - i - 4 < this.#boundary.length) {			//-4表示减去分隔符开始的--以及换行符
 					// 保存数据
 					await this.#resolveData(data.slice(0, i))
 					//剩下的可能时分隔符的内容留着下次处理
@@ -261,13 +239,13 @@ export class MultipartReader {
 				//内容充足，处理内容
 				else {
 					//跳过换行符
-					i += gotbr
+					i += 2
 					//遇到了 -- ，后面很有可能时分隔符，瞧一眼
 					if (data[i] == 45 && data[i + 1] == 45) {
 						//看看是不是遇到了分隔符
 						if (this.#boundary.compare(data, i + 2, i + 2 + this.#boundary.length) == 0) {
 							//保存数据
-							await this.#resolveData(data.slice(0, i - gotbr))
+							await this.#resolveData(data.slice(0, i - 2))			//去除最后的\r\n进行读取
 							//接下来读取分隔符
 							this.#state = ReadState.boundary
 							return { left: data.slice(i), exit: false }