From 4f4201976d71d51cd2579facbef203856e32297c Mon Sep 17 00:00:00 2001
From: Yuxuan Shui <yshuiv7@gmail.com>
Date: Thu, 1 Nov 2018 11:12:20 +0000
Subject: [PATCH] Fix signedness of x properties

Signed-off-by: Yuxuan Shui <yshuiv7@gmail.com>
---
 src/common.h  | 24 ++++++++++++------------
 src/compton.c |  2 +-
 src/types.h   |  8 ++++----
 src/win.c     | 13 ++++---------
 src/x.c       |  6 +++---
 5 files changed, 24 insertions(+), 29 deletions(-)

diff --git a/src/common.h b/src/common.h
index 6fb85d6..d853863 100644
--- a/src/common.h
+++ b/src/common.h
@@ -224,13 +224,13 @@ typedef struct {
 
 /// Structure representing Window property value.
 typedef struct winprop {
-  // All pointers have the same length, right?
-  // I wanted to use anonymous union but it's a GNU extension...
   union {
-    unsigned char *p8;
-    short *p16;
-    long *p32;
-  } data;
+    void *ptr;
+    uint8_t *p8;
+    int16_t *p16;
+    int32_t *p32;
+    uint32_t *c32; // 32bit cardinal
+  };
   unsigned long nitems;
   Atom type;
   int format;
@@ -1570,9 +1570,9 @@ winprop_get_int(winprop_t prop) {
     return 0;
 
   switch (prop.format) {
-    case 8:   tgt = *(prop.data.p8);    break;
-    case 16:  tgt = *(prop.data.p16);   break;
-    case 32:  tgt = *(prop.data.p32);   break;
+    case 8:   tgt = *(prop.p8);    break;
+    case 16:  tgt = *(prop.p16);   break;
+    case 32:  tgt = *(prop.p32);   break;
     default:  assert(0);
               break;
   }
@@ -1592,9 +1592,9 @@ wid_get_text_prop(session_t *ps, Window wid, Atom prop,
 static inline void
 free_winprop(winprop_t *pprop) {
   // Empty the whole structure to avoid possible issues
-  if (pprop->data.p8) {
-    cxfree(pprop->data.p8);
-    pprop->data.p8 = NULL;
+  if (pprop->ptr) {
+    cxfree(pprop->ptr);
+    pprop->ptr = NULL;
   }
   pprop->nitems = 0;
 }
diff --git a/src/compton.c b/src/compton.c
index c37d11c..e976431 100644
--- a/src/compton.c
+++ b/src/compton.c
@@ -912,7 +912,7 @@ get_root_tile(session_t *ps) {
         get_atom(ps, background_props_str[p]),
         1L, XCB_ATOM_PIXMAP, 32);
     if (prop.nitems) {
-      pixmap = *prop.data.p32;
+      pixmap = *prop.p32;
       fill = false;
       free_winprop(&prop);
       break;
diff --git a/src/types.h b/src/types.h
index 1c6114f..f9bf14c 100644
--- a/src/types.h
+++ b/src/types.h
@@ -24,10 +24,10 @@ typedef struct {
 
 /// A structure representing margins around a rectangle.
 typedef struct {
-  int top;
-  int left;
-  int bottom;
-  int right;
+  unsigned int top;
+  unsigned int left;
+  unsigned int bottom;
+  unsigned int right;
 } margin_t;
 
 typedef uint32_t opacity_t;
diff --git a/src/win.c b/src/win.c
index c2d23d2..a1e3d09 100644
--- a/src/win.c
+++ b/src/win.c
@@ -251,7 +251,7 @@ wintype_t wid_get_prop_wintype(session_t *ps, Window wid) {
 
   for (unsigned i = 0; i < prop.nitems; ++i) {
     for (wintype_t j = 1; j < NUM_WINTYPES; ++j) {
-      if (ps->atoms_wintypes[j] == (Atom)prop.data.p32[i]) {
+      if (ps->atoms_wintypes[j] == (xcb_atom_t)prop.p32[i]) {
         free_winprop(&prop);
         return j;
       }
@@ -271,12 +271,7 @@ bool wid_get_opacity_prop(session_t *ps, Window wid, opacity_t def,
   winprop_t prop = wid_get_prop(ps, wid, ps->atom_opacity, 1L, XCB_ATOM_CARDINAL, 32);
 
   if (prop.nitems) {
-    // sanitize the opacity data, if opacity is out of bounds,
-    // assuming they are opaque
-    if (*prop.data.p32 < 0 || *prop.data.p32 > OPAQUE)
-      *out = OPAQUE;
-    else
-      *out = *prop.data.p32;
+    *out = *prop.c32;
     ret = true;
   }
 
@@ -405,7 +400,7 @@ void win_update_prop_shadow_raw(session_t *ps, win *w) {
   if (!prop.nitems) {
     w->prop_shadow = -1;
   } else {
-    w->prop_shadow = *prop.data.p32;
+    w->prop_shadow = *prop.c32;
   }
 
   free_winprop(&prop);
@@ -1236,7 +1231,7 @@ win_update_frame_extents(session_t *ps, win *w, Window client) {
     4L, XCB_ATOM_CARDINAL, 32);
 
   if (prop.nitems == 4) {
-    const long * const extents = prop.data.p32;
+    const uint32_t * const extents = prop.c32;
     const bool changed = w->frame_extents.left != extents[0] ||
                          w->frame_extents.right != extents[1] ||
                          w->frame_extents.top != extents[2] ||
diff --git a/src/x.c b/src/x.c
index 7e8aa3d..25dfedd 100644
--- a/src/x.c
+++ b/src/x.c
@@ -40,7 +40,7 @@ wid_get_prop_adv(const session_t *ps, Window w, Atom atom, long offset,
       && (!rformat || format == rformat)
       && (8 == format || 16 == format || 32 == format)) {
       return (winprop_t) {
-        .data.p8 = data,
+        .ptr = data,
         .nitems = nitems,
         .type = type,
         .format = format,
@@ -50,7 +50,7 @@ wid_get_prop_adv(const session_t *ps, Window w, Atom atom, long offset,
   cxfree(data);
 
   return (winprop_t) {
-    .data.p8 = NULL,
+    .ptr = NULL,
     .nitems = 0,
     .type = AnyPropertyType,
     .format = 0
@@ -70,7 +70,7 @@ wid_get_prop_window(session_t *ps, Window wid, Atom aprop) {
 
   // Return it
   if (prop.nitems) {
-    p = *prop.data.p32;
+    p = *prop.p32;
   }
 
   free_winprop(&prop);