Rewrite XML_ErrorString to use a switch

This makes it a little easier to correlate each enumerator with its
error message, and the compiler should generate a lookup table anyway.

It also avoids running into Clang's -Wsign-compare warning when building
on Windows (where enum's are signed ints):

  error: comparison of integers of different signs: 'enum XML_Error'
  and 'unsigned int' [-Werror,-Wsign-compare]
  if (code > 0 && code < sizeof(message)/sizeof(message[0]))
                  ~~~~ ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

We ran into this when building Chromium on Windows using a recent version of
Clang.

diff --git a/expat/lib/xmlparse.c b/expat/lib/xmlparse.c
index b7e916c8390f023fc282218cd9f22681c6ba073a..8b93902920032fb298c8748cfb726762d92c8ff6 100644 (file)
--- a/expat/lib/xmlparse.c
+++ b/expat/lib/xmlparse.c
@@ -2308,51 +2308,90 @@ XML_DefaultCurrent(XML_Parser parser)
 const XML_LChar * XMLCALL
 XML_ErrorString(enum XML_Error code)
 {
-  static const XML_LChar* const message[] = {
-    0,
-    XML_L("out of memory"),
-    XML_L("syntax error"),
-    XML_L("no element found"),
-    XML_L("not well-formed (invalid token)"),
-    XML_L("unclosed token"),
-    XML_L("partial character"),
-    XML_L("mismatched tag"),
-    XML_L("duplicate attribute"),
-    XML_L("junk after document element"),
-    XML_L("illegal parameter entity reference"),
-    XML_L("undefined entity"),
-    XML_L("recursive entity reference"),
-    XML_L("asynchronous entity"),
-    XML_L("reference to invalid character number"),
-    XML_L("reference to binary entity"),
-    XML_L("reference to external entity in attribute"),
-    XML_L("XML or text declaration not at start of entity"),
-    XML_L("unknown encoding"),
-    XML_L("encoding specified in XML declaration is incorrect"),
-    XML_L("unclosed CDATA section"),
-    XML_L("error in processing external entity reference"),
-    XML_L("document is not standalone"),
-    XML_L("unexpected parser state - please send a bug report"),
-    XML_L("entity declared in parameter entity"),
-    XML_L("requested feature requires XML_DTD support in Expat"),
-    XML_L("cannot change setting once parsing has begun"),
-    XML_L("unbound prefix"),
-    XML_L("must not undeclare prefix"),
-    XML_L("incomplete markup in parameter entity"),
-    XML_L("XML declaration not well-formed"),
-    XML_L("text declaration not well-formed"),
-    XML_L("illegal character(s) in public id"),
-    XML_L("parser suspended"),
-    XML_L("parser not suspended"),
-    XML_L("parsing aborted"),
-    XML_L("parsing finished"),
-    XML_L("cannot suspend in external parameter entity"),
-    XML_L("reserved prefix (xml) must not be undeclared or bound to another namespace name"),
-    XML_L("reserved prefix (xmlns) must not be declared or undeclared"),
-    XML_L("prefix must not be bound to one of the reserved namespace names")
-  };
-  if (code > 0 && code < sizeof(message)/sizeof(message[0]))
-    return message[code];
+  switch (code) {
+  case XML_ERROR_NONE:
+    return NULL;
+  case XML_ERROR_NO_MEMORY:
+    return XML_L("out of memory");
+  case XML_ERROR_SYNTAX:
+    return XML_L("syntax error");
+  case XML_ERROR_NO_ELEMENTS:
+    return XML_L("no element found");
+  case XML_ERROR_INVALID_TOKEN:
+    return XML_L("not well-formed (invalid token)");
+  case XML_ERROR_UNCLOSED_TOKEN:
+    return XML_L("unclosed token");
+  case XML_ERROR_PARTIAL_CHAR:
+    return XML_L("partial character");
+  case XML_ERROR_TAG_MISMATCH:
+    return XML_L("mismatched tag");
+  case XML_ERROR_DUPLICATE_ATTRIBUTE:
+    return XML_L("duplicate attribute");
+  case XML_ERROR_JUNK_AFTER_DOC_ELEMENT:
+    return XML_L("junk after document element");
+  case XML_ERROR_PARAM_ENTITY_REF:
+    return XML_L("illegal parameter entity reference");
+  case XML_ERROR_UNDEFINED_ENTITY:
+    return XML_L("undefined entity");
+  case XML_ERROR_RECURSIVE_ENTITY_REF:
+    return XML_L("recursive entity reference");
+  case XML_ERROR_ASYNC_ENTITY:
+    return XML_L("asynchronous entity");
+  case XML_ERROR_BAD_CHAR_REF:
+    return XML_L("reference to invalid character number");
+  case XML_ERROR_BINARY_ENTITY_REF:
+    return XML_L("reference to binary entity");
+  case XML_ERROR_ATTRIBUTE_EXTERNAL_ENTITY_REF:
+    return XML_L("reference to external entity in attribute");
+  case XML_ERROR_MISPLACED_XML_PI:
+    return XML_L("XML or text declaration not at start of entity");
+  case XML_ERROR_UNKNOWN_ENCODING:
+    return XML_L("unknown encoding");
+  case XML_ERROR_INCORRECT_ENCODING:
+    return XML_L("encoding specified in XML declaration is incorrect");
+  case XML_ERROR_UNCLOSED_CDATA_SECTION:
+    return XML_L("unclosed CDATA section");
+  case XML_ERROR_EXTERNAL_ENTITY_HANDLING:
+    return XML_L("error in processing external entity reference");
+  case XML_ERROR_NOT_STANDALONE:
+    return XML_L("document is not standalone");
+  case XML_ERROR_UNEXPECTED_STATE:
+    return XML_L("unexpected parser state - please send a bug report");
+  case XML_ERROR_ENTITY_DECLARED_IN_PE:
+    return XML_L("entity declared in parameter entity");
+  case XML_ERROR_FEATURE_REQUIRES_XML_DTD:
+    return XML_L("requested feature requires XML_DTD support in Expat");
+  case XML_ERROR_CANT_CHANGE_FEATURE_ONCE_PARSING:
+    return XML_L("cannot change setting once parsing has begun");
+  case XML_ERROR_UNBOUND_PREFIX:
+    return XML_L("unbound prefix");
+  case XML_ERROR_UNDECLARING_PREFIX:
+    return XML_L("must not undeclare prefix");
+  case XML_ERROR_INCOMPLETE_PE:
+    return XML_L("incomplete markup in parameter entity");
+  case XML_ERROR_XML_DECL:
+    return XML_L("XML declaration not well-formed");
+  case XML_ERROR_TEXT_DECL:
+    return XML_L("text declaration not well-formed");
+  case XML_ERROR_PUBLICID:
+    return XML_L("illegal character(s) in public id");
+  case XML_ERROR_SUSPENDED:
+    return XML_L("parser suspended");
+  case XML_ERROR_NOT_SUSPENDED:
+    return XML_L("parser not suspended");
+  case XML_ERROR_ABORTED:
+    return XML_L("parsing aborted");
+  case XML_ERROR_FINISHED:
+    return XML_L("parsing finished");
+  case XML_ERROR_SUSPEND_PE:
+    return XML_L("cannot suspend in external parameter entity");
+  case XML_ERROR_RESERVED_PREFIX_XML:
+    return XML_L("reserved prefix (xml) must not be undeclared or bound to another namespace name");
+  case XML_ERROR_RESERVED_PREFIX_XMLNS:
+    return XML_L("reserved prefix (xmlns) must not be declared or undeclared");
+  case XML_ERROR_RESERVED_NAMESPACE_URI:
+    return XML_L("prefix must not be bound to one of the reserved namespace names");
+  }
   return NULL;
 }