From 0289c2a23213aeceb7c37bbab3a4f5827e36334a Mon Sep 17 00:00:00 2001
From: Jehan <jehan@girinstud.io>
Date: Sat, 28 Nov 2015 16:44:09 +0100
Subject: [PATCH] Differentiate ASCII and detection failure.

The lib used to return "" for both properly detected ASCII and
detection failure. And the tool would return "ascii/unknown".
Make a proper distinction between the 2 cases.
---
 README.md                   |  2 ++
 src/nsUniversalDetector.cpp | 12 ++++++++++--
 src/tools/uchardet.cpp      |  2 +-
 3 files changed, 13 insertions(+), 3 deletions(-)

diff --git a/README.md b/README.md
index 66606b9..ec7542e 100644
--- a/README.md
+++ b/README.md
@@ -45,6 +45,8 @@ Techniques used by universalchardet are described at http://www.mozilla.org/proj
   * French
     * ISO-8859-1
     * ISO-8859-15
+  * English
+    * ASCII
   * Others
     * WINDOWS-1252
 
diff --git a/src/nsUniversalDetector.cpp b/src/nsUniversalDetector.cpp
index f95244e..5e13b81 100644
--- a/src/nsUniversalDetector.cpp
+++ b/src/nsUniversalDetector.cpp
@@ -229,6 +229,12 @@ nsresult nsUniversalDetector::HandleData(const char* aBuf, PRUint32 aLen)
       mDone = PR_TRUE;
       mDetectedCharset = mEscCharSetProber->GetCharSetName();
     }
+    else
+    {
+      /* ASCII with the ESC character (or the sequence "~{") is still
+       * ASCII until proven otherwise. */
+      mDetectedCharset = "ASCII";
+    }
     break;
   case eHighbyte:
     for (i = 0; i < NUM_OF_CHARSET_PROBERS; i++)
@@ -246,8 +252,10 @@ nsresult nsUniversalDetector::HandleData(const char* aBuf, PRUint32 aLen)
     }
     break;
 
-  default:  //pure ascii
-    ;//do nothing here
+  default:
+    /* Pure ASCII */
+    mDetectedCharset = "ASCII";
+    break;
   }
   return NS_OK;
 }
diff --git a/src/tools/uchardet.cpp b/src/tools/uchardet.cpp
index 6ea5131..6f6468b 100644
--- a/src/tools/uchardet.cpp
+++ b/src/tools/uchardet.cpp
@@ -69,7 +69,7 @@ void detect(FILE * fp)
     if (*charset)
     	printf("%s\n", charset);
 	else
-		printf("ascii/unknown\n");
+		printf("unknown\n");
 	
     uchardet_delete(handle);
 }