Start pulling out pieces of the monolithic retain/release checker into
reusable and modular API pieces.
Start by pulling the logic for deriving the Cocoa naming convention
into a separate API, header, and source file.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@94662 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Checker/CocoaConventions.cpp b/lib/Checker/CocoaConventions.cpp
new file mode 100644
index 0000000..456b536
--- /dev/null
+++ b/lib/Checker/CocoaConventions.cpp
@@ -0,0 +1,129 @@
+//===- CocoaConventions.h - Special handling of Cocoa conventions -*- C++ -*--//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file defines
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/Checker/DomainSpecific/CocoaConventions.h"
+#include "llvm/ADT/StringExtras.h"
+
+using namespace clang;
+
+using llvm::StringRef;
+
+// The "fundamental rule" for naming conventions of methods:
+// (url broken into two lines)
+// http://developer.apple.com/documentation/Cocoa/Conceptual/
+// MemoryMgmt/Tasks/MemoryManagementRules.html
+//
+// "You take ownership of an object if you create it using a method whose name
+// begins with "alloc" or "new" or contains "copy" (for example, alloc,
+// newObject, or mutableCopy), or if you send it a retain message. You are
+// responsible for relinquishing ownership of objects you own using release
+// or autorelease. Any other time you receive an object, you must
+// not release it."
+//
+
+static bool isWordEnd(char ch, char prev, char next) {
+ return ch == '\0'
+ || (islower(prev) && isupper(ch)) // xxxC
+ || (isupper(prev) && isupper(ch) && islower(next)) // XXCreate
+ || !isalpha(ch);
+}
+
+static const char* parseWord(const char* s) {
+ char ch = *s, prev = '\0';
+ assert(ch != '\0');
+ char next = *(s+1);
+ while (!isWordEnd(ch, prev, next)) {
+ prev = ch;
+ ch = next;
+ next = *((++s)+1);
+ }
+ return s;
+}
+
+cocoa::NamingConvention cocoa::deriveNamingConvention(Selector S) {
+ IdentifierInfo *II = S.getIdentifierInfoForSlot(0);
+
+ if (!II)
+ return NoConvention;
+
+ const char *s = II->getNameStart();
+
+ // A method/function name may contain a prefix. We don't know it is there,
+ // however, until we encounter the first '_'.
+ bool InPossiblePrefix = true;
+ bool AtBeginning = true;
+ NamingConvention C = NoConvention;
+
+ while (*s != '\0') {
+ // Skip '_'.
+ if (*s == '_') {
+ if (InPossiblePrefix) {
+ // If we already have a convention, return it. Otherwise, skip
+ // the prefix as if it wasn't there.
+ if (C != NoConvention)
+ break;
+
+ InPossiblePrefix = false;
+ AtBeginning = true;
+ assert(C == NoConvention);
+ }
+ ++s;
+ continue;
+ }
+
+ // Skip numbers, ':', etc.
+ if (!isalpha(*s)) {
+ ++s;
+ continue;
+ }
+
+ const char *wordEnd = parseWord(s);
+ assert(wordEnd > s);
+ unsigned len = wordEnd - s;
+
+ switch (len) {
+ default:
+ break;
+ case 3:
+ // Methods starting with 'new' follow the create rule.
+ if (AtBeginning && StringRef(s, len).equals_lower("new"))
+ C = CreateRule;
+ break;
+ case 4:
+ // Methods starting with 'alloc' or contain 'copy' follow the
+ // create rule
+ if (C == NoConvention && StringRef(s, len).equals_lower("copy"))
+ C = CreateRule;
+ else // Methods starting with 'init' follow the init rule.
+ if (AtBeginning && StringRef(s, len).equals_lower("init"))
+ C = InitRule;
+ break;
+ case 5:
+ if (AtBeginning && StringRef(s, len).equals_lower("alloc"))
+ C = CreateRule;
+ break;
+ }
+
+ // If we aren't in the prefix and have a derived convention then just
+ // return it now.
+ if (!InPossiblePrefix && C != NoConvention)
+ return C;
+
+ AtBeginning = false;
+ s = wordEnd;
+ }
+
+ // We will get here if there wasn't more than one word
+ // after the prefix.
+ return C;
+}