Objective-C. Under a special flag, -Wcstring-format-directive,

off by default, issue a warning if %s directive is used in
certain CF/NS formatting APIs, to assist user in deprecating
use of such %s in these APIs. rdar://18182443

llvm-svn: 217467

1 files changed, 45 insertions, 9 deletions

diff --git a/clang/lib/Analysis/PrintfFormatString.cpp b/clang/lib/Analysis/PrintfFormatString.cpp
index c6453b66549..146635b8870 100644
--- a/clang/lib/Analysis/PrintfFormatString.cpp
+++ b/clang/lib/Analysis/PrintfFormatString.cpp
@@ -54,7 +54,8 @@ static PrintfSpecifierResult ParsePrintfSpecifier(FormatStringHandler &H,
                                                   const char *E,
                                                   unsigned &argIndex,
                                                   const LangOptions &LO,
-                                                  const TargetInfo &Target) {
+                                                  const TargetInfo &Target,
+                                                  bool Warn) {
 
   using namespace clang::analyze_format_string;
   using namespace clang::analyze_printf;
@@ -83,7 +84,8 @@ static PrintfSpecifierResult ParsePrintfSpecifier(FormatStringHandler &H,
 
   if (I == E) {
     // No more characters left?
-    H.HandleIncompleteSpecifier(Start, E - Start);
+    if (Warn)
+      H.HandleIncompleteSpecifier(Start, E - Start);
     return true;
   }
 
@@ -93,7 +95,8 @@ static PrintfSpecifierResult ParsePrintfSpecifier(FormatStringHandler &H,
 
   if (I == E) {
     // No more characters left?
-    H.HandleIncompleteSpecifier(Start, E - Start);
+    if (Warn)
+      H.HandleIncompleteSpecifier(Start, E - Start);
     return true;
   }
 
@@ -118,7 +121,8 @@ static PrintfSpecifierResult ParsePrintfSpecifier(FormatStringHandler &H,
 
   if (I == E) {
     // No more characters left?
-    H.HandleIncompleteSpecifier(Start, E - Start);
+    if (Warn)
+      H.HandleIncompleteSpecifier(Start, E - Start);
     return true;
   }
 
@@ -129,7 +133,8 @@ static PrintfSpecifierResult ParsePrintfSpecifier(FormatStringHandler &H,
 
   if (I == E) {
     // No more characters left?
-    H.HandleIncompleteSpecifier(Start, E - Start);
+    if (Warn)
+      H.HandleIncompleteSpecifier(Start, E - Start);
     return true;
   }
 
@@ -137,7 +142,8 @@ static PrintfSpecifierResult ParsePrintfSpecifier(FormatStringHandler &H,
   if (*I == '.') {
     ++I;
     if (I == E) {
-      H.HandleIncompleteSpecifier(Start, E - Start);
+      if (Warn)
+        H.HandleIncompleteSpecifier(Start, E - Start);
       return true;
     }
 
@@ -147,7 +153,8 @@ static PrintfSpecifierResult ParsePrintfSpecifier(FormatStringHandler &H,
 
     if (I == E) {
       // No more characters left?
-      H.HandleIncompleteSpecifier(Start, E - Start);
+      if (Warn)
+        H.HandleIncompleteSpecifier(Start, E - Start);
       return true;
     }
   }
@@ -155,7 +162,8 @@ static PrintfSpecifierResult ParsePrintfSpecifier(FormatStringHandler &H,
   // Look for the length modifier.
   if (ParseLengthModifier(FS, I, E, LO) && I == E) {
     // No more characters left?
-    H.HandleIncompleteSpecifier(Start, E - Start);
+    if (Warn)
+      H.HandleIncompleteSpecifier(Start, E - Start);
     return true;
   }
 
@@ -239,7 +247,7 @@ bool clang::analyze_format_string::ParsePrintfString(FormatStringHandler &H,
   // Keep looking for a format specifier until we have exhausted the string.
   while (I != E) {
     const PrintfSpecifierResult &FSR = ParsePrintfSpecifier(H, I, E, argIndex,
-                                                            LO, Target);
+                                                            LO, Target, true);
     // Did a fail-stop error of any kind occur when parsing the specifier?
     // If so, don't do any more processing.
     if (FSR.shouldStop())
@@ -257,6 +265,34 @@ bool clang::analyze_format_string::ParsePrintfString(FormatStringHandler &H,
   return false;
 }
 
+bool clang::analyze_format_string::ParseFormatStringHasSArg(const char *I,
+                                                            const char *E,
+                                                            const LangOptions &LO,
+                                                            const TargetInfo &Target) {
+  
+  unsigned argIndex = 0;
+  
+  // Keep looking for a %s format specifier until we have exhausted the string.
+  FormatStringHandler H;
+  while (I != E) {
+    const PrintfSpecifierResult &FSR = ParsePrintfSpecifier(H, I, E, argIndex,
+                                                            LO, Target, false);
+    // Did a fail-stop error of any kind occur when parsing the specifier?
+    // If so, don't do any more processing.
+    if (FSR.shouldStop())
+      return false;
+    // Did we exhaust the string or encounter an error that
+    // we can recover from?
+    if (!FSR.hasValue())
+      continue;
+    const analyze_printf::PrintfSpecifier &FS = FSR.getValue();
+    // Return true if this a %s format specifier.
+    if (FS.getConversionSpecifier().getKind() == ConversionSpecifier::Kind::sArg)
+      return true;
+  }
+  return false;
+}
+
 //===----------------------------------------------------------------------===//
 // Methods on PrintfSpecifier.
 //===----------------------------------------------------------------------===//