From 76a1f4ac381d583c1ece86e76c108e81bec3e3c2 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Iv=C3=A1n=20S=C3=A1nchez=20Ortega?= <ivan@mazemap.no>
Date: Tue, 21 Feb 2017 12:47:35 +0100
Subject: [PATCH 1/3] Accept #rgba and #rrggbbaa notation

---
 csscolorparser.js | 27 +++++++++++++++++++++------
 1 file changed, 21 insertions(+), 6 deletions(-)

diff --git a/csscolorparser.js b/csscolorparser.js
index 4dba075..e97759c 100644
--- a/csscolorparser.js
+++ b/csscolorparser.js
@@ -138,20 +138,35 @@ function parseCSSColor(css_str) {
 
   // #abc and #abc123 syntax.
   if (str[0] === '#') {
+    var iv = parseInt(str.substr(1), 16);  // TODO(deanm): Stricter parsing.
     if (str.length === 4) {
-      var iv = parseInt(str.substr(1), 16);  // TODO(deanm): Stricter parsing.
+      // #rgb
       if (!(iv >= 0 && iv <= 0xfff)) return null;  // Covers NaN.
       return [((iv & 0xf00) >> 4) | ((iv & 0xf00) >> 8),
-              (iv & 0xf0) | ((iv & 0xf0) >> 4),
-              (iv & 0xf) | ((iv & 0xf) << 4),
+               (iv & 0x0f0)       | ((iv & 0x0f0) >> 4),
+              ((iv & 0x00f) << 4) |  (iv & 0x00f),
               1];
     } else if (str.length === 7) {
-      var iv = parseInt(str.substr(1), 16);  // TODO(deanm): Stricter parsing.
+      // #rrggbb
       if (!(iv >= 0 && iv <= 0xffffff)) return null;  // Covers NaN.
       return [(iv & 0xff0000) >> 16,
-              (iv & 0xff00) >> 8,
-              iv & 0xff,
+              (iv & 0x00ff00) >> 8,
+               iv & 0x0000ff,
               1];
+    } else if (str.length === 5) {
+      // #rgba
+      if (!(iv >= 0 && iv <= 0xffff)) return null;  // Covers NaN.
+      return [((iv & 0xf000) >> 8) | ((iv & 0xf000) >> 12),
+              ((iv & 0x0f00) >> 4) | ((iv & 0x0f00) >> 8),
+               (iv & 0x00f0)       | ((iv & 0x00f0) >> 4),
+              ((iv & 0x000f) << 4  |  (iv & 0x000f)) / 256];
+    } else if (str.length === 9) {
+      // #rrggbbaa
+      if (!(iv >= 0 && iv <= 0xffffffff)) return null;  // Covers NaN.
+      return [(iv & 0xff000000) >> 24,
+              (iv & 0x00ff0000) >> 16,
+              (iv & 0x0000ff00) >> 8,
+              (iv & 0x000000ff) / 256];
     }
 
     return null;

From 1e15484d4aa53fe1c633b9f29d6ef8ad88754c19 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Iv=C3=A1n=20S=C3=A1nchez=20Ortega?= <ivan@mazemap.no>
Date: Tue, 21 Feb 2017 14:11:52 +0100
Subject: [PATCH 2/3] Work around complement-2 negative numers when
 right-shifting 32-bit ints

---
 csscolorparser.js | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/csscolorparser.js b/csscolorparser.js
index e97759c..c9c4159 100644
--- a/csscolorparser.js
+++ b/csscolorparser.js
@@ -163,10 +163,10 @@ function parseCSSColor(css_str) {
     } else if (str.length === 9) {
       // #rrggbbaa
       if (!(iv >= 0 && iv <= 0xffffffff)) return null;  // Covers NaN.
-      return [(iv & 0xff000000) >> 24,
-              (iv & 0x00ff0000) >> 16,
-              (iv & 0x0000ff00) >> 8,
-              (iv & 0x000000ff) / 256];
+      return [((iv & 0xff000000) >> 24) & 0xff,
+               (iv & 0x00ff0000) >> 16,
+               (iv & 0x0000ff00) >> 8,
+               (iv & 0x000000ff) / 256];
     }
 
     return null;

From 8e84a5b972054be1c2d1a15bd604dfd63380c91d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Iv=C3=A1n=20S=C3=A1nchez=20Ortega?= <ivan@mazemap.no>
Date: Tue, 21 Feb 2017 15:11:09 +0100
Subject: [PATCH 3/3] Divide alpha byte by 255, not by 256, because 0xff => 1.0

---
 csscolorparser.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/csscolorparser.js b/csscolorparser.js
index c9c4159..d1be6a1 100644
--- a/csscolorparser.js
+++ b/csscolorparser.js
@@ -159,14 +159,14 @@ function parseCSSColor(css_str) {
       return [((iv & 0xf000) >> 8) | ((iv & 0xf000) >> 12),
               ((iv & 0x0f00) >> 4) | ((iv & 0x0f00) >> 8),
                (iv & 0x00f0)       | ((iv & 0x00f0) >> 4),
-              ((iv & 0x000f) << 4  |  (iv & 0x000f)) / 256];
+              ((iv & 0x000f) << 4  |  (iv & 0x000f)) / 255];
     } else if (str.length === 9) {
       // #rrggbbaa
       if (!(iv >= 0 && iv <= 0xffffffff)) return null;  // Covers NaN.
       return [((iv & 0xff000000) >> 24) & 0xff,
                (iv & 0x00ff0000) >> 16,
                (iv & 0x0000ff00) >> 8,
-               (iv & 0x000000ff) / 256];
+               (iv & 0x000000ff) / 255];
     }
 
     return null;