llvm-project/clang/lib/AST/PrintfFormatString.cpp

1127 lines
36 KiB
C++

//== PrintfFormatString.cpp - Analysis of printf format strings --*- C++ -*-==//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// Handling of format string in printf and friends. The structure of format
// strings for fprintf() are described in C99 7.19.6.1.
//
//===----------------------------------------------------------------------===//
#include "FormatStringParsing.h"
#include "clang/AST/FormatString.h"
#include "clang/AST/OSLog.h"
#include "clang/Basic/TargetInfo.h"
#include "llvm/Support/Regex.h"
using clang::analyze_format_string::ArgType;
using clang::analyze_format_string::FormatStringHandler;
using clang::analyze_format_string::LengthModifier;
using clang::analyze_format_string::OptionalAmount;
using clang::analyze_format_string::ConversionSpecifier;
using clang::analyze_printf::PrintfSpecifier;
using namespace clang;
typedef clang::analyze_format_string::SpecifierResult<PrintfSpecifier>
PrintfSpecifierResult;
//===----------------------------------------------------------------------===//
// Methods for parsing format strings.
//===----------------------------------------------------------------------===//
using analyze_format_string::ParseNonPositionAmount;
static bool ParsePrecision(FormatStringHandler &H, PrintfSpecifier &FS,
const char *Start, const char *&Beg, const char *E,
unsigned *argIndex) {
if (argIndex) {
FS.setPrecision(ParseNonPositionAmount(Beg, E, *argIndex));
} else {
const OptionalAmount Amt = ParsePositionAmount(H, Start, Beg, E,
analyze_format_string::PrecisionPos);
if (Amt.isInvalid())
return true;
FS.setPrecision(Amt);
}
return false;
}
static bool ParseObjCFlags(FormatStringHandler &H, PrintfSpecifier &FS,
const char *FlagBeg, const char *E, bool Warn) {
StringRef Flag(FlagBeg, E - FlagBeg);
// Currently there is only one flag.
if (Flag == "tt") {
FS.setHasObjCTechnicalTerm(FlagBeg);
return false;
}
// Handle either the case of no flag or an invalid flag.
if (Warn) {
if (Flag == "")
H.HandleEmptyObjCModifierFlag(FlagBeg, E - FlagBeg);
else
H.HandleInvalidObjCModifierFlag(FlagBeg, E - FlagBeg);
}
return true;
}
static PrintfSpecifierResult ParsePrintfSpecifier(FormatStringHandler &H,
const char *&Beg,
const char *E,
unsigned &argIndex,
const LangOptions &LO,
const TargetInfo &Target,
bool Warn,
bool isFreeBSDKPrintf) {
using namespace clang::analyze_format_string;
using namespace clang::analyze_printf;
const char *I = Beg;
const char *Start = nullptr;
UpdateOnReturn <const char*> UpdateBeg(Beg, I);
// Look for a '%' character that indicates the start of a format specifier.
for ( ; I != E ; ++I) {
char c = *I;
if (c == '\0') {
// Detect spurious null characters, which are likely errors.
H.HandleNullChar(I);
return true;
}
if (c == '%') {
Start = I++; // Record the start of the format specifier.
break;
}
}
// No format specifier found?
if (!Start)
return false;
if (I == E) {
// No more characters left?
if (Warn)
H.HandleIncompleteSpecifier(Start, E - Start);
return true;
}
PrintfSpecifier FS;
if (ParseArgPosition(H, FS, Start, I, E))
return true;
if (I == E) {
// No more characters left?
if (Warn)
H.HandleIncompleteSpecifier(Start, E - Start);
return true;
}
if (*I == '{') {
++I;
unsigned char PrivacyFlags = 0;
StringRef MatchedStr;
do {
StringRef Str(I, E - I);
std::string Match = "^[[:space:]]*"
"(private|public|sensitive|mask\\.[^[:space:],}]*)"
"[[:space:]]*(,|})";
llvm::Regex R(Match);
SmallVector<StringRef, 2> Matches;
if (R.match(Str, &Matches)) {
MatchedStr = Matches[1];
I += Matches[0].size();
// Set the privacy flag if the privacy annotation in the
// comma-delimited segment is at least as strict as the privacy
// annotations in previous comma-delimited segments.
if (MatchedStr.startswith("mask")) {
StringRef MaskType = MatchedStr.substr(sizeof("mask.") - 1);
unsigned Size = MaskType.size();
if (Warn && (Size == 0 || Size > 8))
H.handleInvalidMaskType(MaskType);
FS.setMaskType(MaskType);
} else if (MatchedStr.equals("sensitive"))
PrivacyFlags = clang::analyze_os_log::OSLogBufferItem::IsSensitive;
else if (PrivacyFlags !=
clang::analyze_os_log::OSLogBufferItem::IsSensitive &&
MatchedStr.equals("private"))
PrivacyFlags = clang::analyze_os_log::OSLogBufferItem::IsPrivate;
else if (PrivacyFlags == 0 && MatchedStr.equals("public"))
PrivacyFlags = clang::analyze_os_log::OSLogBufferItem::IsPublic;
} else {
size_t CommaOrBracePos =
Str.find_if([](char c) { return c == ',' || c == '}'; });
if (CommaOrBracePos == StringRef::npos) {
// Neither a comma nor the closing brace was found.
if (Warn)
H.HandleIncompleteSpecifier(Start, E - Start);
return true;
}
I += CommaOrBracePos + 1;
}
// Continue until the closing brace is found.
} while (*(I - 1) == ',');
// Set the privacy flag.
switch (PrivacyFlags) {
case 0:
break;
case clang::analyze_os_log::OSLogBufferItem::IsPrivate:
FS.setIsPrivate(MatchedStr.data());
break;
case clang::analyze_os_log::OSLogBufferItem::IsPublic:
FS.setIsPublic(MatchedStr.data());
break;
case clang::analyze_os_log::OSLogBufferItem::IsSensitive:
FS.setIsSensitive(MatchedStr.data());
break;
default:
llvm_unreachable("Unexpected privacy flag value");
}
}
// Look for flags (if any).
bool hasMore = true;
for ( ; I != E; ++I) {
switch (*I) {
default: hasMore = false; break;
case '\'':
// FIXME: POSIX specific. Always accept?
FS.setHasThousandsGrouping(I);
break;
case '-': FS.setIsLeftJustified(I); break;
case '+': FS.setHasPlusPrefix(I); break;
case ' ': FS.setHasSpacePrefix(I); break;
case '#': FS.setHasAlternativeForm(I); break;
case '0': FS.setHasLeadingZeros(I); break;
}
if (!hasMore)
break;
}
if (I == E) {
// No more characters left?
if (Warn)
H.HandleIncompleteSpecifier(Start, E - Start);
return true;
}
// Look for the field width (if any).
if (ParseFieldWidth(H, FS, Start, I, E,
FS.usesPositionalArg() ? nullptr : &argIndex))
return true;
if (I == E) {
// No more characters left?
if (Warn)
H.HandleIncompleteSpecifier(Start, E - Start);
return true;
}
// Look for the precision (if any).
if (*I == '.') {
++I;
if (I == E) {
if (Warn)
H.HandleIncompleteSpecifier(Start, E - Start);
return true;
}
if (ParsePrecision(H, FS, Start, I, E,
FS.usesPositionalArg() ? nullptr : &argIndex))
return true;
if (I == E) {
// No more characters left?
if (Warn)
H.HandleIncompleteSpecifier(Start, E - Start);
return true;
}
}
if (ParseVectorModifier(H, FS, I, E, LO))
return true;
// Look for the length modifier.
if (ParseLengthModifier(FS, I, E, LO) && I == E) {
// No more characters left?
if (Warn)
H.HandleIncompleteSpecifier(Start, E - Start);
return true;
}
// Look for the Objective-C modifier flags, if any.
// We parse these here, even if they don't apply to
// the conversion specifier, and then emit an error
// later if the conversion specifier isn't '@'. This
// enables better recovery, and we don't know if
// these flags are applicable until later.
const char *ObjCModifierFlagsStart = nullptr,
*ObjCModifierFlagsEnd = nullptr;
if (*I == '[') {
ObjCModifierFlagsStart = I;
++I;
auto flagStart = I;
for (;; ++I) {
ObjCModifierFlagsEnd = I;
if (I == E) {
if (Warn)
H.HandleIncompleteSpecifier(Start, E - Start);
return true;
}
// Did we find the closing ']'?
if (*I == ']') {
if (ParseObjCFlags(H, FS, flagStart, I, Warn))
return true;
++I;
break;
}
// There are no separators defined yet for multiple
// Objective-C modifier flags. When those are
// defined, this is the place to check.
}
}
if (*I == '\0') {
// Detect spurious null characters, which are likely errors.
H.HandleNullChar(I);
return true;
}
// Finally, look for the conversion specifier.
const char *conversionPosition = I++;
ConversionSpecifier::Kind k = ConversionSpecifier::InvalidSpecifier;
switch (*conversionPosition) {
default:
break;
// C99: 7.19.6.1 (section 8).
case '%': k = ConversionSpecifier::PercentArg; break;
case 'A': k = ConversionSpecifier::AArg; break;
case 'E': k = ConversionSpecifier::EArg; break;
case 'F': k = ConversionSpecifier::FArg; break;
case 'G': k = ConversionSpecifier::GArg; break;
case 'X': k = ConversionSpecifier::XArg; break;
case 'a': k = ConversionSpecifier::aArg; break;
case 'c': k = ConversionSpecifier::cArg; break;
case 'd': k = ConversionSpecifier::dArg; break;
case 'e': k = ConversionSpecifier::eArg; break;
case 'f': k = ConversionSpecifier::fArg; break;
case 'g': k = ConversionSpecifier::gArg; break;
case 'i': k = ConversionSpecifier::iArg; break;
case 'n':
// Not handled, but reserved in OpenCL.
if (!LO.OpenCL)
k = ConversionSpecifier::nArg;
break;
case 'o': k = ConversionSpecifier::oArg; break;
case 'p': k = ConversionSpecifier::pArg; break;
case 's': k = ConversionSpecifier::sArg; break;
case 'u': k = ConversionSpecifier::uArg; break;
case 'x': k = ConversionSpecifier::xArg; break;
// POSIX specific.
case 'C': k = ConversionSpecifier::CArg; break;
case 'S': k = ConversionSpecifier::SArg; break;
// Apple extension for os_log
case 'P':
k = ConversionSpecifier::PArg;
break;
// Objective-C.
case '@': k = ConversionSpecifier::ObjCObjArg; break;
// Glibc specific.
case 'm': k = ConversionSpecifier::PrintErrno; break;
// FreeBSD kernel specific.
case 'b':
if (isFreeBSDKPrintf)
k = ConversionSpecifier::FreeBSDbArg; // int followed by char *
break;
case 'r':
if (isFreeBSDKPrintf)
k = ConversionSpecifier::FreeBSDrArg; // int
break;
case 'y':
if (isFreeBSDKPrintf)
k = ConversionSpecifier::FreeBSDyArg; // int
break;
// Apple-specific.
case 'D':
if (isFreeBSDKPrintf)
k = ConversionSpecifier::FreeBSDDArg; // void * followed by char *
else if (Target.getTriple().isOSDarwin())
k = ConversionSpecifier::DArg;
break;
case 'O':
if (Target.getTriple().isOSDarwin())
k = ConversionSpecifier::OArg;
break;
case 'U':
if (Target.getTriple().isOSDarwin())
k = ConversionSpecifier::UArg;
break;
// MS specific.
case 'Z':
if (Target.getTriple().isOSMSVCRT())
k = ConversionSpecifier::ZArg;
break;
}
// Check to see if we used the Objective-C modifier flags with
// a conversion specifier other than '@'.
if (k != ConversionSpecifier::ObjCObjArg &&
k != ConversionSpecifier::InvalidSpecifier &&
ObjCModifierFlagsStart) {
H.HandleObjCFlagsWithNonObjCConversion(ObjCModifierFlagsStart,
ObjCModifierFlagsEnd + 1,
conversionPosition);
return true;
}
PrintfConversionSpecifier CS(conversionPosition, k);
FS.setConversionSpecifier(CS);
if (CS.consumesDataArgument() && !FS.usesPositionalArg())
FS.setArgIndex(argIndex++);
// FreeBSD kernel specific.
if (k == ConversionSpecifier::FreeBSDbArg ||
k == ConversionSpecifier::FreeBSDDArg)
argIndex++;
if (k == ConversionSpecifier::InvalidSpecifier) {
unsigned Len = I - Start;
if (ParseUTF8InvalidSpecifier(Start, E, Len)) {
CS.setEndScanList(Start + Len);
FS.setConversionSpecifier(CS);
}
// Assume the conversion takes one argument.
return !H.HandleInvalidPrintfConversionSpecifier(FS, Start, Len);
}
return PrintfSpecifierResult(Start, FS);
}
bool clang::analyze_format_string::ParsePrintfString(FormatStringHandler &H,
const char *I,
const char *E,
const LangOptions &LO,
const TargetInfo &Target,
bool isFreeBSDKPrintf) {
unsigned argIndex = 0;
// 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, true,
isFreeBSDKPrintf);
// 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 true;
// Did we exhaust the string or encounter an error that
// we can recover from?
if (!FSR.hasValue())
continue;
// We have a format specifier. Pass it to the callback.
if (!H.HandlePrintfSpecifier(FSR.getValue(), FSR.getStart(),
I - FSR.getStart(), Target))
return true;
}
assert(I == E && "Format string not exhausted");
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,
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;
}
bool clang::analyze_format_string::parseFormatStringHasFormattingSpecifiers(
const char *Begin, const char *End, const LangOptions &LO,
const TargetInfo &Target) {
unsigned ArgIndex = 0;
// Keep looking for a formatting specifier until we have exhausted the string.
FormatStringHandler H;
while (Begin != End) {
const PrintfSpecifierResult &FSR =
ParsePrintfSpecifier(H, Begin, End, ArgIndex, LO, Target, false, false);
if (FSR.shouldStop())
break;
if (FSR.hasValue())
return true;
}
return false;
}
//===----------------------------------------------------------------------===//
// Methods on PrintfSpecifier.
//===----------------------------------------------------------------------===//
ArgType PrintfSpecifier::getScalarArgType(ASTContext &Ctx,
bool IsObjCLiteral) const {
if (CS.getKind() == ConversionSpecifier::cArg)
switch (LM.getKind()) {
case LengthModifier::None:
return Ctx.IntTy;
case LengthModifier::AsLong:
case LengthModifier::AsWide:
return ArgType(ArgType::WIntTy, "wint_t");
case LengthModifier::AsShort:
if (Ctx.getTargetInfo().getTriple().isOSMSVCRT())
return Ctx.IntTy;
LLVM_FALLTHROUGH;
default:
return ArgType::Invalid();
}
if (CS.isIntArg())
switch (LM.getKind()) {
case LengthModifier::AsLongDouble:
// GNU extension.
return Ctx.LongLongTy;
case LengthModifier::None:
case LengthModifier::AsShortLong:
return Ctx.IntTy;
case LengthModifier::AsInt32:
return ArgType(Ctx.IntTy, "__int32");
case LengthModifier::AsChar:
return ArgType::AnyCharTy;
case LengthModifier::AsShort: return Ctx.ShortTy;
case LengthModifier::AsLong: return Ctx.LongTy;
case LengthModifier::AsLongLong:
case LengthModifier::AsQuad:
return Ctx.LongLongTy;
case LengthModifier::AsInt64:
return ArgType(Ctx.LongLongTy, "__int64");
case LengthModifier::AsIntMax:
return ArgType(Ctx.getIntMaxType(), "intmax_t");
case LengthModifier::AsSizeT:
return ArgType::makeSizeT(ArgType(Ctx.getSignedSizeType(), "ssize_t"));
case LengthModifier::AsInt3264:
return Ctx.getTargetInfo().getTriple().isArch64Bit()
? ArgType(Ctx.LongLongTy, "__int64")
: ArgType(Ctx.IntTy, "__int32");
case LengthModifier::AsPtrDiff:
return ArgType::makePtrdiffT(
ArgType(Ctx.getPointerDiffType(), "ptrdiff_t"));
case LengthModifier::AsAllocate:
case LengthModifier::AsMAllocate:
case LengthModifier::AsWide:
return ArgType::Invalid();
}
if (CS.isUIntArg())
switch (LM.getKind()) {
case LengthModifier::AsLongDouble:
// GNU extension.
return Ctx.UnsignedLongLongTy;
case LengthModifier::None:
case LengthModifier::AsShortLong:
return Ctx.UnsignedIntTy;
case LengthModifier::AsInt32:
return ArgType(Ctx.UnsignedIntTy, "unsigned __int32");
case LengthModifier::AsChar: return Ctx.UnsignedCharTy;
case LengthModifier::AsShort: return Ctx.UnsignedShortTy;
case LengthModifier::AsLong: return Ctx.UnsignedLongTy;
case LengthModifier::AsLongLong:
case LengthModifier::AsQuad:
return Ctx.UnsignedLongLongTy;
case LengthModifier::AsInt64:
return ArgType(Ctx.UnsignedLongLongTy, "unsigned __int64");
case LengthModifier::AsIntMax:
return ArgType(Ctx.getUIntMaxType(), "uintmax_t");
case LengthModifier::AsSizeT:
return ArgType::makeSizeT(ArgType(Ctx.getSizeType(), "size_t"));
case LengthModifier::AsInt3264:
return Ctx.getTargetInfo().getTriple().isArch64Bit()
? ArgType(Ctx.UnsignedLongLongTy, "unsigned __int64")
: ArgType(Ctx.UnsignedIntTy, "unsigned __int32");
case LengthModifier::AsPtrDiff:
return ArgType::makePtrdiffT(
ArgType(Ctx.getUnsignedPointerDiffType(), "unsigned ptrdiff_t"));
case LengthModifier::AsAllocate:
case LengthModifier::AsMAllocate:
case LengthModifier::AsWide:
return ArgType::Invalid();
}
if (CS.isDoubleArg()) {
if (!VectorNumElts.isInvalid()) {
switch (LM.getKind()) {
case LengthModifier::AsShort:
return Ctx.HalfTy;
case LengthModifier::AsShortLong:
return Ctx.FloatTy;
case LengthModifier::AsLong:
default:
return Ctx.DoubleTy;
}
}
if (LM.getKind() == LengthModifier::AsLongDouble)
return Ctx.LongDoubleTy;
return Ctx.DoubleTy;
}
if (CS.getKind() == ConversionSpecifier::nArg) {
switch (LM.getKind()) {
case LengthModifier::None:
return ArgType::PtrTo(Ctx.IntTy);
case LengthModifier::AsChar:
return ArgType::PtrTo(Ctx.SignedCharTy);
case LengthModifier::AsShort:
return ArgType::PtrTo(Ctx.ShortTy);
case LengthModifier::AsLong:
return ArgType::PtrTo(Ctx.LongTy);
case LengthModifier::AsLongLong:
case LengthModifier::AsQuad:
return ArgType::PtrTo(Ctx.LongLongTy);
case LengthModifier::AsIntMax:
return ArgType::PtrTo(ArgType(Ctx.getIntMaxType(), "intmax_t"));
case LengthModifier::AsSizeT:
return ArgType::PtrTo(ArgType(Ctx.getSignedSizeType(), "ssize_t"));
case LengthModifier::AsPtrDiff:
return ArgType::PtrTo(ArgType(Ctx.getPointerDiffType(), "ptrdiff_t"));
case LengthModifier::AsLongDouble:
return ArgType(); // FIXME: Is this a known extension?
case LengthModifier::AsAllocate:
case LengthModifier::AsMAllocate:
case LengthModifier::AsInt32:
case LengthModifier::AsInt3264:
case LengthModifier::AsInt64:
case LengthModifier::AsWide:
return ArgType::Invalid();
case LengthModifier::AsShortLong:
llvm_unreachable("only used for OpenCL which doesn not handle nArg");
}
}
switch (CS.getKind()) {
case ConversionSpecifier::sArg:
if (LM.getKind() == LengthModifier::AsWideChar) {
if (IsObjCLiteral)
return ArgType(Ctx.getPointerType(Ctx.UnsignedShortTy.withConst()),
"const unichar *");
return ArgType(ArgType::WCStrTy, "wchar_t *");
}
if (LM.getKind() == LengthModifier::AsWide)
return ArgType(ArgType::WCStrTy, "wchar_t *");
return ArgType::CStrTy;
case ConversionSpecifier::SArg:
if (IsObjCLiteral)
return ArgType(Ctx.getPointerType(Ctx.UnsignedShortTy.withConst()),
"const unichar *");
if (Ctx.getTargetInfo().getTriple().isOSMSVCRT() &&
LM.getKind() == LengthModifier::AsShort)
return ArgType::CStrTy;
return ArgType(ArgType::WCStrTy, "wchar_t *");
case ConversionSpecifier::CArg:
if (IsObjCLiteral)
return ArgType(Ctx.UnsignedShortTy, "unichar");
if (Ctx.getTargetInfo().getTriple().isOSMSVCRT() &&
LM.getKind() == LengthModifier::AsShort)
return Ctx.IntTy;
return ArgType(Ctx.WideCharTy, "wchar_t");
case ConversionSpecifier::pArg:
case ConversionSpecifier::PArg:
return ArgType::CPointerTy;
case ConversionSpecifier::ObjCObjArg:
return ArgType::ObjCPointerTy;
default:
break;
}
// FIXME: Handle other cases.
return ArgType();
}
ArgType PrintfSpecifier::getArgType(ASTContext &Ctx,
bool IsObjCLiteral) const {
const PrintfConversionSpecifier &CS = getConversionSpecifier();
if (!CS.consumesDataArgument())
return ArgType::Invalid();
ArgType ScalarTy = getScalarArgType(Ctx, IsObjCLiteral);
if (!ScalarTy.isValid() || VectorNumElts.isInvalid())
return ScalarTy;
return ScalarTy.makeVectorType(Ctx, VectorNumElts.getConstantAmount());
}
bool PrintfSpecifier::fixType(QualType QT, const LangOptions &LangOpt,
ASTContext &Ctx, bool IsObjCLiteral) {
// %n is different from other conversion specifiers; don't try to fix it.
if (CS.getKind() == ConversionSpecifier::nArg)
return false;
// Handle Objective-C objects first. Note that while the '%@' specifier will
// not warn for structure pointer or void pointer arguments (because that's
// how CoreFoundation objects are implemented), we only show a fixit for '%@'
// if we know it's an object (block, id, class, or __attribute__((NSObject))).
if (QT->isObjCRetainableType()) {
if (!IsObjCLiteral)
return false;
CS.setKind(ConversionSpecifier::ObjCObjArg);
// Disable irrelevant flags
HasThousandsGrouping = false;
HasPlusPrefix = false;
HasSpacePrefix = false;
HasAlternativeForm = false;
HasLeadingZeroes = false;
Precision.setHowSpecified(OptionalAmount::NotSpecified);
LM.setKind(LengthModifier::None);
return true;
}
// Handle strings next (char *, wchar_t *)
if (QT->isPointerType() && (QT->getPointeeType()->isAnyCharacterType())) {
CS.setKind(ConversionSpecifier::sArg);
// Disable irrelevant flags
HasAlternativeForm = false;
HasLeadingZeroes = false;
// Set the long length modifier for wide characters
if (QT->getPointeeType()->isWideCharType())
LM.setKind(LengthModifier::AsWideChar);
else
LM.setKind(LengthModifier::None);
return true;
}
// If it's an enum, get its underlying type.
if (const EnumType *ETy = QT->getAs<EnumType>())
QT = ETy->getDecl()->getIntegerType();
const BuiltinType *BT = QT->getAs<BuiltinType>();
if (!BT) {
const VectorType *VT = QT->getAs<VectorType>();
if (VT) {
QT = VT->getElementType();
BT = QT->getAs<BuiltinType>();
VectorNumElts = OptionalAmount(VT->getNumElements());
}
}
// We can only work with builtin types.
if (!BT)
return false;
// Set length modifier
switch (BT->getKind()) {
case BuiltinType::Bool:
case BuiltinType::WChar_U:
case BuiltinType::WChar_S:
case BuiltinType::Char8: // FIXME: Treat like 'char'?
case BuiltinType::Char16:
case BuiltinType::Char32:
case BuiltinType::UInt128:
case BuiltinType::Int128:
case BuiltinType::Half:
case BuiltinType::BFloat16:
case BuiltinType::Float16:
case BuiltinType::Float128:
case BuiltinType::Ibm128:
case BuiltinType::ShortAccum:
case BuiltinType::Accum:
case BuiltinType::LongAccum:
case BuiltinType::UShortAccum:
case BuiltinType::UAccum:
case BuiltinType::ULongAccum:
case BuiltinType::ShortFract:
case BuiltinType::Fract:
case BuiltinType::LongFract:
case BuiltinType::UShortFract:
case BuiltinType::UFract:
case BuiltinType::ULongFract:
case BuiltinType::SatShortAccum:
case BuiltinType::SatAccum:
case BuiltinType::SatLongAccum:
case BuiltinType::SatUShortAccum:
case BuiltinType::SatUAccum:
case BuiltinType::SatULongAccum:
case BuiltinType::SatShortFract:
case BuiltinType::SatFract:
case BuiltinType::SatLongFract:
case BuiltinType::SatUShortFract:
case BuiltinType::SatUFract:
case BuiltinType::SatULongFract:
// Various types which are non-trivial to correct.
return false;
#define IMAGE_TYPE(ImgType, Id, SingletonId, Access, Suffix) \
case BuiltinType::Id:
#include "clang/Basic/OpenCLImageTypes.def"
#define EXT_OPAQUE_TYPE(ExtType, Id, Ext) \
case BuiltinType::Id:
#include "clang/Basic/OpenCLExtensionTypes.def"
#define SVE_TYPE(Name, Id, SingletonId) \
case BuiltinType::Id:
#include "clang/Basic/AArch64SVEACLETypes.def"
#define PPC_VECTOR_TYPE(Name, Id, Size) \
case BuiltinType::Id:
#include "clang/Basic/PPCTypes.def"
#define RVV_TYPE(Name, Id, SingletonId) case BuiltinType::Id:
#include "clang/Basic/RISCVVTypes.def"
#define SIGNED_TYPE(Id, SingletonId)
#define UNSIGNED_TYPE(Id, SingletonId)
#define FLOATING_TYPE(Id, SingletonId)
#define BUILTIN_TYPE(Id, SingletonId) \
case BuiltinType::Id:
#include "clang/AST/BuiltinTypes.def"
// Misc other stuff which doesn't make sense here.
return false;
case BuiltinType::UInt:
case BuiltinType::Int:
case BuiltinType::Float:
LM.setKind(VectorNumElts.isInvalid() ?
LengthModifier::None : LengthModifier::AsShortLong);
break;
case BuiltinType::Double:
LM.setKind(VectorNumElts.isInvalid() ?
LengthModifier::None : LengthModifier::AsLong);
break;
case BuiltinType::Char_U:
case BuiltinType::UChar:
case BuiltinType::Char_S:
case BuiltinType::SChar:
LM.setKind(LengthModifier::AsChar);
break;
case BuiltinType::Short:
case BuiltinType::UShort:
LM.setKind(LengthModifier::AsShort);
break;
case BuiltinType::Long:
case BuiltinType::ULong:
LM.setKind(LengthModifier::AsLong);
break;
case BuiltinType::LongLong:
case BuiltinType::ULongLong:
LM.setKind(LengthModifier::AsLongLong);
break;
case BuiltinType::LongDouble:
LM.setKind(LengthModifier::AsLongDouble);
break;
}
// Handle size_t, ptrdiff_t, etc. that have dedicated length modifiers in C99.
if (isa<TypedefType>(QT) && (LangOpt.C99 || LangOpt.CPlusPlus11))
namedTypeToLengthModifier(QT, LM);
// If fixing the length modifier was enough, we might be done.
if (hasValidLengthModifier(Ctx.getTargetInfo(), LangOpt)) {
// If we're going to offer a fix anyway, make sure the sign matches.
switch (CS.getKind()) {
case ConversionSpecifier::uArg:
case ConversionSpecifier::UArg:
if (QT->isSignedIntegerType())
CS.setKind(clang::analyze_format_string::ConversionSpecifier::dArg);
break;
case ConversionSpecifier::dArg:
case ConversionSpecifier::DArg:
case ConversionSpecifier::iArg:
if (QT->isUnsignedIntegerType() && !HasPlusPrefix)
CS.setKind(clang::analyze_format_string::ConversionSpecifier::uArg);
break;
default:
// Other specifiers do not have signed/unsigned variants.
break;
}
const analyze_printf::ArgType &ATR = getArgType(Ctx, IsObjCLiteral);
if (ATR.isValid() && ATR.matchesType(Ctx, QT))
return true;
}
// Set conversion specifier and disable any flags which do not apply to it.
// Let typedefs to char fall through to int, as %c is silly for uint8_t.
if (!isa<TypedefType>(QT) && QT->isCharType()) {
CS.setKind(ConversionSpecifier::cArg);
LM.setKind(LengthModifier::None);
Precision.setHowSpecified(OptionalAmount::NotSpecified);
HasAlternativeForm = false;
HasLeadingZeroes = false;
HasPlusPrefix = false;
}
// Test for Floating type first as LongDouble can pass isUnsignedIntegerType
else if (QT->isRealFloatingType()) {
CS.setKind(ConversionSpecifier::fArg);
}
else if (QT->isSignedIntegerType()) {
CS.setKind(ConversionSpecifier::dArg);
HasAlternativeForm = false;
}
else if (QT->isUnsignedIntegerType()) {
CS.setKind(ConversionSpecifier::uArg);
HasAlternativeForm = false;
HasPlusPrefix = false;
} else {
llvm_unreachable("Unexpected type");
}
return true;
}
void PrintfSpecifier::toString(raw_ostream &os) const {
// Whilst some features have no defined order, we are using the order
// appearing in the C99 standard (ISO/IEC 9899:1999 (E) 7.19.6.1)
os << "%";
// Positional args
if (usesPositionalArg()) {
os << getPositionalArgIndex() << "$";
}
// Conversion flags
if (IsLeftJustified) os << "-";
if (HasPlusPrefix) os << "+";
if (HasSpacePrefix) os << " ";
if (HasAlternativeForm) os << "#";
if (HasLeadingZeroes) os << "0";
// Minimum field width
FieldWidth.toString(os);
// Precision
Precision.toString(os);
// Vector modifier
if (!VectorNumElts.isInvalid())
os << 'v' << VectorNumElts.getConstantAmount();
// Length modifier
os << LM.toString();
// Conversion specifier
os << CS.toString();
}
bool PrintfSpecifier::hasValidPlusPrefix() const {
if (!HasPlusPrefix)
return true;
// The plus prefix only makes sense for signed conversions
switch (CS.getKind()) {
case ConversionSpecifier::dArg:
case ConversionSpecifier::DArg:
case ConversionSpecifier::iArg:
case ConversionSpecifier::fArg:
case ConversionSpecifier::FArg:
case ConversionSpecifier::eArg:
case ConversionSpecifier::EArg:
case ConversionSpecifier::gArg:
case ConversionSpecifier::GArg:
case ConversionSpecifier::aArg:
case ConversionSpecifier::AArg:
case ConversionSpecifier::FreeBSDrArg:
case ConversionSpecifier::FreeBSDyArg:
return true;
default:
return false;
}
}
bool PrintfSpecifier::hasValidAlternativeForm() const {
if (!HasAlternativeForm)
return true;
// Alternate form flag only valid with the oxXaAeEfFgG conversions
switch (CS.getKind()) {
case ConversionSpecifier::oArg:
case ConversionSpecifier::OArg:
case ConversionSpecifier::xArg:
case ConversionSpecifier::XArg:
case ConversionSpecifier::aArg:
case ConversionSpecifier::AArg:
case ConversionSpecifier::eArg:
case ConversionSpecifier::EArg:
case ConversionSpecifier::fArg:
case ConversionSpecifier::FArg:
case ConversionSpecifier::gArg:
case ConversionSpecifier::GArg:
case ConversionSpecifier::FreeBSDrArg:
case ConversionSpecifier::FreeBSDyArg:
return true;
default:
return false;
}
}
bool PrintfSpecifier::hasValidLeadingZeros() const {
if (!HasLeadingZeroes)
return true;
// Leading zeroes flag only valid with the diouxXaAeEfFgG conversions
switch (CS.getKind()) {
case ConversionSpecifier::dArg:
case ConversionSpecifier::DArg:
case ConversionSpecifier::iArg:
case ConversionSpecifier::oArg:
case ConversionSpecifier::OArg:
case ConversionSpecifier::uArg:
case ConversionSpecifier::UArg:
case ConversionSpecifier::xArg:
case ConversionSpecifier::XArg:
case ConversionSpecifier::aArg:
case ConversionSpecifier::AArg:
case ConversionSpecifier::eArg:
case ConversionSpecifier::EArg:
case ConversionSpecifier::fArg:
case ConversionSpecifier::FArg:
case ConversionSpecifier::gArg:
case ConversionSpecifier::GArg:
case ConversionSpecifier::FreeBSDrArg:
case ConversionSpecifier::FreeBSDyArg:
return true;
default:
return false;
}
}
bool PrintfSpecifier::hasValidSpacePrefix() const {
if (!HasSpacePrefix)
return true;
// The space prefix only makes sense for signed conversions
switch (CS.getKind()) {
case ConversionSpecifier::dArg:
case ConversionSpecifier::DArg:
case ConversionSpecifier::iArg:
case ConversionSpecifier::fArg:
case ConversionSpecifier::FArg:
case ConversionSpecifier::eArg:
case ConversionSpecifier::EArg:
case ConversionSpecifier::gArg:
case ConversionSpecifier::GArg:
case ConversionSpecifier::aArg:
case ConversionSpecifier::AArg:
case ConversionSpecifier::FreeBSDrArg:
case ConversionSpecifier::FreeBSDyArg:
return true;
default:
return false;
}
}
bool PrintfSpecifier::hasValidLeftJustified() const {
if (!IsLeftJustified)
return true;
// The left justified flag is valid for all conversions except n
switch (CS.getKind()) {
case ConversionSpecifier::nArg:
return false;
default:
return true;
}
}
bool PrintfSpecifier::hasValidThousandsGroupingPrefix() const {
if (!HasThousandsGrouping)
return true;
switch (CS.getKind()) {
case ConversionSpecifier::dArg:
case ConversionSpecifier::DArg:
case ConversionSpecifier::iArg:
case ConversionSpecifier::uArg:
case ConversionSpecifier::UArg:
case ConversionSpecifier::fArg:
case ConversionSpecifier::FArg:
case ConversionSpecifier::gArg:
case ConversionSpecifier::GArg:
return true;
default:
return false;
}
}
bool PrintfSpecifier::hasValidPrecision() const {
if (Precision.getHowSpecified() == OptionalAmount::NotSpecified)
return true;
// Precision is only valid with the diouxXaAeEfFgGsP conversions
switch (CS.getKind()) {
case ConversionSpecifier::dArg:
case ConversionSpecifier::DArg:
case ConversionSpecifier::iArg:
case ConversionSpecifier::oArg:
case ConversionSpecifier::OArg:
case ConversionSpecifier::uArg:
case ConversionSpecifier::UArg:
case ConversionSpecifier::xArg:
case ConversionSpecifier::XArg:
case ConversionSpecifier::aArg:
case ConversionSpecifier::AArg:
case ConversionSpecifier::eArg:
case ConversionSpecifier::EArg:
case ConversionSpecifier::fArg:
case ConversionSpecifier::FArg:
case ConversionSpecifier::gArg:
case ConversionSpecifier::GArg:
case ConversionSpecifier::sArg:
case ConversionSpecifier::FreeBSDrArg:
case ConversionSpecifier::FreeBSDyArg:
case ConversionSpecifier::PArg:
return true;
default:
return false;
}
}
bool PrintfSpecifier::hasValidFieldWidth() const {
if (FieldWidth.getHowSpecified() == OptionalAmount::NotSpecified)
return true;
// The field width is valid for all conversions except n
switch (CS.getKind()) {
case ConversionSpecifier::nArg:
return false;
default:
return true;
}
}