From 48918f28d9b4e7f36258743035e940aa704a831f Mon Sep 17 00:00:00 2001
From: "Enrico Weigelt, metux IT consult" <info@metux.net>
Date: Wed, 24 Jul 2024 17:37:57 +0200
Subject: [PATCH] Xext: panoramiX: PanoramiXGetImage() reply payload in one
 block

Simplify writing reply payload into just one block.
This also makes further simplifications by subsequent patches easier.

Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
---
 Xext/panoramiXprocs.c | 49 ++++++++++++++++++-------------------------
 1 file changed, 20 insertions(+), 29 deletions(-)

diff --git a/Xext/panoramiXprocs.c b/Xext/panoramiXprocs.c
index 2cff60990..72982919a 100644
--- a/Xext/panoramiXprocs.c
+++ b/Xext/panoramiXprocs.c
@@ -1960,7 +1960,6 @@ PanoramiXGetImage(ClientPtr client)
     DrawablePtr pDraw;
     PanoramiXRes *draw;
     Bool isRoot;
-    char *pBuf;
     int i, x, y, w, h, format, rc;
     Mask plane = 0, planemask;
     int linesDone, nlines, linesPerBuf;
@@ -2032,7 +2031,6 @@ PanoramiXGetImage(ClientPtr client)
                                               IncludeInferiors);
     }
 
-
     if (format == ZPixmap) {
         widthBytesLine = PixmapBytePad(w, pDraw->depth);
         length = widthBytesLine * h;
@@ -2046,14 +2044,6 @@ PanoramiXGetImage(ClientPtr client)
 
     }
 
-    xGetImageReply rep = {
-        .type = X_Reply,
-        .sequenceNumber = client->sequence,
-        .visual = wVisual(((WindowPtr) pDraw)),
-        .depth = pDraw->depth,
-        .length = bytes_to_int32(length),
-    };
-
     if (widthBytesLine == 0 || h == 0)
         linesPerBuf = 0;
     else if (widthBytesLine >= XINERAMA_IMAGE_BUFSIZE)
@@ -2063,15 +2053,9 @@ PanoramiXGetImage(ClientPtr client)
         if (linesPerBuf > h)
             linesPerBuf = h;
     }
-    if (!(pBuf = calloc(linesPerBuf, widthBytesLine)))
-        return BadAlloc;
 
-    if (client->swapped) {
-        swaps(&rep.sequenceNumber);
-        swapl(&rep.length);
-        swapl(&rep.visual);
-    }
-    WriteToClient(client, sizeof(rep), &rep);
+    char *payload = calloc(1, length);
+    char *walk = payload;
 
     if (linesPerBuf == 0) {
         /* nothing to do */
@@ -2081,14 +2065,11 @@ PanoramiXGetImage(ClientPtr client)
         while (h - linesDone > 0) {
             nlines = min(linesPerBuf, h - linesDone);
 
-            if (pDraw->depth == 1)
-                memset(pBuf, 0, nlines * widthBytesLine);
-
             XineramaGetImageData(drawables, x, y + linesDone, w, nlines,
-                                 format, planemask, pBuf, widthBytesLine,
+                                 format, planemask, walk, widthBytesLine,
                                  isRoot);
 
-            WriteToClient(client, (int) (nlines * widthBytesLine), pBuf);
+            walk += nlines * widthBytesLine;
             linesDone += nlines;
         }
     }
@@ -2099,20 +2080,30 @@ PanoramiXGetImage(ClientPtr client)
                 while (h - linesDone > 0) {
                     nlines = min(linesPerBuf, h - linesDone);
 
-                    memset(pBuf, 0, nlines * widthBytesLine);
-
                     XineramaGetImageData(drawables, x, y + linesDone, w,
-                                         nlines, format, plane, pBuf,
+                                         nlines, format, plane, walk,
                                          widthBytesLine, isRoot);
 
-                    WriteToClient(client, (int)(nlines * widthBytesLine), pBuf);
-
+                    walk += nlines * widthBytesLine;
                     linesDone += nlines;
                 }
             }
         }
     }
-    free(pBuf);
+
+    xGetImageReply xgi = {
+        .type = X_Reply,
+        .sequenceNumber = client->sequence,
+        .visual = wVisual(((WindowPtr) pDraw)),
+        .depth = pDraw->depth,
+        .length = bytes_to_int32(length),
+    };
+
+    WriteReplyToClient(client, sizeof(xGetImageReply), &xgi);
+
+    if (length)
+        WriteToClient(client, length, payload);
+
     return Success;
 }