io: Make xmlOutputBufferCreate* not free encoder on error

Revert a530ff12 which was an inadvertent API change.

xmlIO.c

@@ -1509,7 +1509,7 @@ xmlAllocParserInputBuffer(xmlCharEncoding enc) {
 /**
  * Create a buffered parser output
  *
- * Consumes `encoder` even in error case.
+ * Consumes `encoder` but not in error case.
  *
  * @param encoder  the encoding converter or NULL
  * @returns the new parser output or NULL
@@ -1520,13 +1520,11 @@ xmlAllocOutputBuffer(xmlCharEncodingHandlerPtr encoder) {
 
     ret = (xmlOutputBufferPtr) xmlMalloc(sizeof(xmlOutputBuffer));
     if (ret == NULL) {
-        xmlCharEncCloseFunc(encoder);
 	return(NULL);
     }
     memset(ret, 0, sizeof(xmlOutputBuffer));
     ret->buffer = xmlBufCreate(MINLEN);
     if (ret->buffer == NULL) {
-        xmlCharEncCloseFunc(encoder);
         xmlFree(ret);
 	return(NULL);
     }
@@ -1535,7 +1533,8 @@ xmlAllocOutputBuffer(xmlCharEncodingHandlerPtr encoder) {
     if (encoder != NULL) {
         ret->conv = xmlBufCreate(MINLEN);
 	if (ret->conv == NULL) {
-            xmlOutputBufferClose(ret);
+            xmlBufFree(ret->buffer);
+            xmlFree(ret);
 	    return(NULL);
 	}
 
@@ -1778,7 +1777,6 @@ __xmlOutputBufferCreateFilename(const char *URI,
      * Allocate the Output buffer front-end.
      */
     ret = xmlAllocOutputBuffer(encoder);
-    encoder = NULL;
     if (ret == NULL)
         goto error;
 
@@ -1807,14 +1805,14 @@ __xmlOutputBufferCreateFilename(const char *URI,
     }
 
     if (ret->context == NULL) {
+        /* Don't free encoder */
+        ret->encoder = NULL;
         xmlOutputBufferClose(ret);
 	ret = NULL;
     }
 
 error:
     xmlFree(unescaped);
-    if (encoder != NULL)
-        xmlCharEncCloseFunc(encoder);
     return(ret);
 }
 
@@ -1824,7 +1822,7 @@ error:
  * Automatic support for ZLIB/Compress compressed document is provided
  * by default if found at compile-time.
  *
- * Consumes `encoder` even in error case.
+ * Consumes `encoder` but not in error case.
  *
  * @param URI  a C string containing the URI or filename
  * @param encoder  the encoding converter or NULL
@@ -1877,7 +1875,7 @@ xmlParserInputBufferCreateFile(FILE *file, xmlCharEncoding enc) {
  * Create a buffered output for the progressive saving to a `FILE *`
  * buffered C I/O.
  *
- * Consumes `encoder` even in error case.
+ * Consumes `encoder` but not in error case.
  *
  * @param file  a `FILE *`
  * @param encoder  the encoding converter or NULL
@@ -1888,7 +1886,6 @@ xmlOutputBufferCreateFile(FILE *file, xmlCharEncodingHandlerPtr encoder) {
     xmlOutputBufferPtr ret;
 
     if (file == NULL) {
-        xmlCharEncCloseFunc(encoder);
         return(NULL);
     }
 
@@ -1905,7 +1902,7 @@ xmlOutputBufferCreateFile(FILE *file, xmlCharEncodingHandlerPtr encoder) {
 /**
  * Create a buffered output for the progressive saving to a xmlBuffer
  *
- * Consumes `encoder` even in error case.
+ * Consumes `encoder` but not in error case.
  *
  * @param buffer  a xmlBufferPtr
  * @param encoder  the encoding converter or NULL
@@ -1917,7 +1914,6 @@ xmlOutputBufferCreateBuffer(xmlBufferPtr buffer,
     xmlOutputBufferPtr ret;
 
     if (buffer == NULL) {
-        xmlCharEncCloseFunc(encoder);
         return(NULL);
     }
 
@@ -2167,7 +2163,7 @@ xmlNewInputBufferString(const char *str, xmlParserInputFlags flags) {
  * Create a buffered output for the progressive saving
  * to a file descriptor
  *
- * Consumes `encoder` even in error case.
+ * Consumes `encoder` but not in error case.
  *
  * @param fd  a file descriptor number
  * @param encoder  the encoding converter or NULL
@@ -2178,7 +2174,6 @@ xmlOutputBufferCreateFd(int fd, xmlCharEncodingHandlerPtr encoder) {
     xmlOutputBufferPtr ret;
 
     if (fd < 0) {
-        xmlCharEncCloseFunc(encoder);
         return(NULL);
     }
 
@@ -2239,7 +2234,7 @@ xmlParserInputBufferCreateIO(xmlInputReadCallback   ioread,
  * Create a buffered output for the progressive saving
  * to an I/O handler
  *
- * Consumes `encoder` even in error case.
+ * Consumes `encoder` but not in error case.
  *
  * @param iowrite  an I/O write function
  * @param ioclose  an I/O close function
@@ -2254,7 +2249,6 @@ xmlOutputBufferCreateIO(xmlOutputWriteCallback   iowrite,
     xmlOutputBufferPtr ret;
 
     if (iowrite == NULL) {
-        xmlCharEncCloseFunc(encoder);
         return(NULL);
     }