Read expected buffer size (#17409)

* Read expected buffer size.

* Changed name.

4 files changed, 15 insertions, 14 deletions

diff --git a/routers/common/repo.go b/routers/common/repo.go
index af9170164e..b0e14b63f5 100644
--- a/routers/common/repo.go
+++ b/routers/common/repo.go
@@ -18,6 +18,7 @@ import (
 	"code.gitea.io/gitea/modules/log"
 	"code.gitea.io/gitea/modules/setting"
 	"code.gitea.io/gitea/modules/typesniffer"
+	"code.gitea.io/gitea/modules/util"
 )
 
 // ServeBlob download a git.Blob
@@ -42,8 +43,8 @@ func ServeBlob(ctx *context.Context, blob *git.Blob) error {
 // ServeData download file from io.Reader
 func ServeData(ctx *context.Context, name string, size int64, reader io.Reader) error {
 	buf := make([]byte, 1024)
-	n, err := reader.Read(buf)
-	if err != nil && err != io.EOF {
+	n, err := util.ReadAtMost(reader, buf)
+	if err != nil {
 		return err
 	}
 	if n >= 0 {
diff --git a/routers/web/repo/editor.go b/routers/web/repo/editor.go
index 1d18bfe9a9..f272583499 100644
--- a/routers/web/repo/editor.go
+++ b/routers/web/repo/editor.go
@@ -118,7 +118,7 @@ func editFile(ctx *context.Context, isNewFile bool) {
 		ctx.Data["FileName"] = blob.Name()
 
 		buf := make([]byte, 1024)
-		n, _ := dataRc.Read(buf)
+		n, _ := util.ReadAtMost(dataRc, buf)
 		buf = buf[:n]
 
 		// Only some file types are editable online as text.
@@ -751,7 +751,7 @@ func UploadFileToServer(ctx *context.Context) {
 	defer file.Close()
 
 	buf := make([]byte, 1024)
-	n, _ := file.Read(buf)
+	n, _ := util.ReadAtMost(file, buf)
 	if n > 0 {
 		buf = buf[:n]
 	}
diff --git a/routers/web/repo/lfs.go b/routers/web/repo/lfs.go
index 271c638553..5e24cfa3c0 100644
--- a/routers/web/repo/lfs.go
+++ b/routers/web/repo/lfs.go
@@ -25,6 +25,7 @@ import (
 	"code.gitea.io/gitea/modules/setting"
 	"code.gitea.io/gitea/modules/storage"
 	"code.gitea.io/gitea/modules/typesniffer"
+	"code.gitea.io/gitea/modules/util"
 )
 
 const (
@@ -271,7 +272,7 @@ func LFSFileGet(ctx *context.Context) {
 	}
 	defer dataRc.Close()
 	buf := make([]byte, 1024)
-	n, err := dataRc.Read(buf)
+	n, err := util.ReadAtMost(dataRc, buf)
 	if err != nil {
 		ctx.ServerError("Data", err)
 		return
@@ -296,10 +297,10 @@ func LFSFileGet(ctx *context.Context) {
 			break
 		}
 
-		buf := charset.ToUTF8WithFallbackReader(io.MultiReader(bytes.NewReader(buf), dataRc))
+		rd := charset.ToUTF8WithFallbackReader(io.MultiReader(bytes.NewReader(buf), dataRc))
 
 		// Building code view blocks with line number on server side.
-		fileContent, _ := io.ReadAll(buf)
+		fileContent, _ := io.ReadAll(rd)
 
 		var output bytes.Buffer
 		lines := strings.Split(string(fileContent), "\n")
diff --git a/routers/web/repo/view.go b/routers/web/repo/view.go
index 0777a10e7b..90be631c73 100644
--- a/routers/web/repo/view.go
+++ b/routers/web/repo/view.go
@@ -33,6 +33,7 @@ import (
 	"code.gitea.io/gitea/modules/setting"
 	"code.gitea.io/gitea/modules/structs"
 	"code.gitea.io/gitea/modules/typesniffer"
+	"code.gitea.io/gitea/modules/util"
 )
 
 const (
@@ -250,7 +251,7 @@ func renderDirectory(ctx *context.Context, treeLink string) {
 		defer dataRc.Close()
 
 		buf := make([]byte, 1024)
-		n, _ := dataRc.Read(buf)
+		n, _ := util.ReadAtMost(dataRc, buf)
 		buf = buf[:n]
 
 		st := typesniffer.DetectContentType(buf)
@@ -285,7 +286,7 @@ func renderDirectory(ctx *context.Context, treeLink string) {
 					defer dataRc.Close()
 
 					buf = make([]byte, 1024)
-					n, err = dataRc.Read(buf)
+					n, err = util.ReadAtMost(dataRc, buf)
 					if err != nil {
 						ctx.ServerError("Data", err)
 						return
@@ -377,7 +378,7 @@ func renderFile(ctx *context.Context, entry *git.TreeEntry, treeLink, rawLink st
 	ctx.Data["RawFileLink"] = rawLink + "/" + ctx.Repo.TreePath
 
 	buf := make([]byte, 1024)
-	n, _ := dataRc.Read(buf)
+	n, _ := util.ReadAtMost(dataRc, buf)
 	buf = buf[:n]
 
 	st := typesniffer.DetectContentType(buf)
@@ -409,10 +410,8 @@ func renderFile(ctx *context.Context, entry *git.TreeEntry, treeLink, rawLink st
 				defer dataRc.Close()
 
 				buf = make([]byte, 1024)
-				n, err = dataRc.Read(buf)
-				// Error EOF don't mean there is an error, it just means we read to
-				// the end
-				if err != nil && err != io.EOF {
+				n, err = util.ReadAtMost(dataRc, buf)
+				if err != nil {
 					ctx.ServerError("Data", err)
 					return
 				}