[flang-commits] [flang] [flang][runtime] Enforce proper termination of list-directed input va… (PR #66244)
via flang-commits
flang-commits at lists.llvm.org
Wed Sep 13 10:03:06 PDT 2023
llvmbot wrote:
<!--LLVM PR SUMMARY COMMENT-->
@llvm/pr-subscribers-flang-runtime
<details>
<summary>Changes</summary>
…lues
Emit an error at runtime when a list-directed input value is not followed by a value separator or end of record. Previously, the runtime I/O library was consuming as many input characters that were valid for the type of the value, and leaving any remaining characters for the next input edit, if any.
--
Full diff: https://github.com/llvm/llvm-project/pull/66244.diff
3 Files Affected:
- (modified) flang/include/flang/Runtime/iostat.h (+1)
- (modified) flang/runtime/edit-input.cpp (+107-32)
- (modified) flang/runtime/iostat.cpp (+2)
<pre>
diff --git a/flang/include/flang/Runtime/iostat.h b/flang/include/flang/Runtime/iostat.h
index faadaab8e90ffa9..0456e24f4e381ba 100644
--- a/flang/include/flang/Runtime/iostat.h
+++ b/flang/include/flang/Runtime/iostat.h
@@ -84,6 +84,7 @@ enum Iostat {
IostatBadFlushUnit,
IostatBadOpOnChildUnit,
IostatBadNewUnit,
+ IostatBadListDirectedInputSeparator,
};
const char *IostatErrorString(int);
diff --git a/flang/runtime/edit-input.cpp b/flang/runtime/edit-input.cpp
index 98627c9dd82750a..a89612ab74640fb 100644
--- a/flang/runtime/edit-input.cpp
+++ b/flang/runtime/edit-input.cpp
@@ -16,6 +16,49 @@
namespace Fortran::runtime::io {
+// Checks that a list-directed input value has been entirely consumed and
+// doesn't contain unparsed characters before the next value separator.
+static inline bool IsCharValueSeparator(const DataEdit &edit, char32_t ch) {
+ char32_t comma{
+ edit.modes.editingFlags & decimalComma ? char32_t{';'} : char32_t{','}};
+ return ch == ' ' || ch == '\t' || ch == '/' || ch == comma;
+}
+
+static inline bool IsListDirectedFieldComplete(
+ IoStatementState &io, const DataEdit &edit) {
+ std::size_t byteCount;
+ if (auto ch{io.GetCurrentChar(byteCount)}) {
+ return IsCharValueSeparator(edit, *ch);
+ } else {
+ return true; // end of record: ok
+ }
+}
+
+static bool CheckCompleteListDirectedField(
+ IoStatementState &io, const DataEdit &edit) {
+ if (edit.IsListDirected()) {
+ std::size_t byteCount;
+ if (auto ch{io.GetCurrentChar(byteCount)}) {
+ if (IsCharValueSeparator(edit, *ch)) {
+ return true;
+ } else {
+ const auto &connection{io.GetConnectionState()};
+ io.GetIoErrorHandler().SignalError(IostatBadListDirectedInputSeparator,
+ "invalid character (0x%x) after list-directed input value, "
+ "at column %d in record %d",
+ static_cast<unsigned>(*ch),
+ static_cast<int>(connection.positionInRecord + 1),
+ static_cast<int>(connection.currentRecordNumber));
+ return false;
+ }
+ } else {
+ return true; // end of record: ok
+ }
+ } else {
+ return true;
+ }
+}
+
template <int LOG2_BASE>
static bool EditBOZInput(
IoStatementState &io, const DataEdit &edit, void *n, std::size_t bytes) {
@@ -89,28 +132,29 @@ static bool EditBOZInput(
*data |= digit << shift;
shift -= LOG2_BASE;
}
- return true;
+ return CheckCompleteListDirectedField(io, edit);
}
static inline char32_t GetDecimalPoint(const DataEdit &edit) {
return edit.modes.editingFlags & decimalComma ? char32_t{','} : char32_t{'.'};
}
-// Prepares input from a field, and consumes the sign, if any.
-// Returns true if there's a '-' sign.
-static bool ScanNumericPrefix(IoStatementState &io, const DataEdit &edit,
+// Prepares input from a field, and returns the sign, if any, else '\0'.
+static char ScanNumericPrefix(IoStatementState &io, const DataEdit &edit,
std::optional<char32_t> &next, std::optional<int> &remaining) {
remaining = io.CueUpInput(edit);
next = io.NextInField(remaining, edit);
- bool negative{false};
+ char sign{'\0'};
if (next) {
- negative = *next == '-';
- if (negative || *next == '+') {
- io.SkipSpaces(remaining);
+ if (*next == '-' || *next == '+') {
+ sign = *next;
+ if (!edit.IsListDirected()) {
+ io.SkipSpaces(remaining);
+ }
next = io.NextInField(remaining, edit);
}
}
- return negative;
+ return sign;
}
bool EditIntegerInput(
@@ -141,9 +185,9 @@ bool EditIntegerInput(
}
std::optional<int> remaining;
std::optional<char32_t> next;
- bool negate{ScanNumericPrefix(io, edit, next, remaining)};
+ char sign{ScanNumericPrefix(io, edit, next, remaining)};
common::UnsignedInt128 value{0};
- bool any{negate};
+ bool any{!!sign};
bool overflow{false};
for (; next; next = io.NextInField(remaining, edit)) {
char32_t ch{*next};
@@ -178,13 +222,13 @@ bool EditIntegerInput(
return false;
}
auto maxForKind{common::UnsignedInt128{1} << ((8 * kind) - 1)};
- overflow |= value >= maxForKind && (value > maxForKind || !negate);
+ overflow |= value >= maxForKind && (value > maxForKind || sign != '-');
if (overflow) {
io.GetIoErrorHandler().SignalError(IostatIntegerInputOverflow,
"Decimal input overflows INTEGER(%d) variable", kind);
return false;
}
- if (negate) {
+ if (sign == '-') {
value = -value;
}
if (any || !io.GetConnectionState().IsAtEOF()) {
@@ -212,13 +256,17 @@ static int ScanRealInput(char *buffer, int bufferSize, IoStatementState &io,
}
++got;
}};
- if (ScanNumericPrefix(io, edit, next, remaining)) {
+ char sign{ScanNumericPrefix(io, edit, next, remaining)};
+ if (sign == '-') {
Put('-');
}
bool bzMode{(edit.modes.editingFlags & blankZero) != 0};
- if (!next || (!bzMode && *next == ' ')) { // empty/blank field means zero
- remaining.reset();
- if (!io.GetConnectionState().IsAtEOF()) {
+ if (!next || (!bzMode && *next == ' ')) {
+ if (!edit.IsListDirected() && !io.GetConnectionState().IsAtEOF()) {
+ // An empty/blank field means zero when not list-directed.
+ // A fixed-width field containing only a sign is also zero;
+ // this behavior isn't standard-conforming in F'2023 but it is
+ // required to pass FCVS.
Put('0');
}
return got;
@@ -286,6 +334,10 @@ static int ScanRealInput(char *buffer, int bufferSize, IoStatementState &io,
// the FCVS suite.
Put('0'); // emit at least one digit
}
+ // In list-directed input, a bad exponent is not consumed.
+ auto nextBeforeExponent{next};
+ auto startExponent{io.GetConnectionState().positionInRecord};
+ bool hasGoodExponent{false};
if (next &&
(*next == 'e' || *next == 'E' || *next == 'd' || *next == 'D' ||
*next == 'q' || *next == 'Q')) {
@@ -306,11 +358,13 @@ static int ScanRealInput(char *buffer, int bufferSize, IoStatementState &io,
}
for (exponent = 0; next; next = io.NextInField(remaining, edit)) {
if (*next >= '0' && *next <= '9') {
+ hasGoodExponent = true;
if (exponent < 10000) {
exponent = 10 * exponent + *next - '0';
}
} else if (*next == ' ' || *next == '\t') {
if (bzMode) {
+ hasGoodExponent = true;
exponent = 10 * exponent;
}
} else {
@@ -321,6 +375,11 @@ static int ScanRealInput(char *buffer, int bufferSize, IoStatementState &io,
exponent = -exponent;
}
}
+ if (!hasGoodExponent) {
+ // There isn't a good exponent; do not consume it.
+ next = nextBeforeExponent;
+ io.HandleAbsolutePosition(startExponent);
+ }
if (decimalPoint) {
exponent += *decimalPoint;
} else {
@@ -339,6 +398,7 @@ static int ScanRealInput(char *buffer, int bufferSize, IoStatementState &io,
// input value.
if (edit.descriptor == DataEdit::ListDirectedImaginaryPart) {
if (next && (*next == ' ' || *next == '\t')) {
+ io.SkipSpaces(remaining);
next = io.NextInField(remaining, edit);
}
if (!next) { // NextInField fails on separators like ')'
@@ -423,19 +483,26 @@ static bool TryFastPathRealInput(
return false;
}
}
- for (; p < limit && (*p == ' ' || *p == '\t'); ++p) {
- }
if (edit.descriptor == DataEdit::ListDirectedImaginaryPart) {
- // Need to consume a trailing ')' and any white space after
- if (p >= limit || *p != ')') {
+ // Need to consume a trailing ')', possibly with leading spaces
+ for (; p < limit && (*p == ' ' || *p == '\t'); ++p) {
+ }
+ if (p < limit && *p == ')') {
+ ++p;
+ } else {
+ return false;
+ }
+ } else if (edit.IsListDirected()) {
+ if (p < limit && !IsCharValueSeparator(edit, *p)) {
return false;
}
- for (++p; p < limit && (*p == ' ' || *p == '\t'); ++p) {
+ } else {
+ for (; p < limit && (*p == ' ' || *p == '\t'); ++p) {
+ }
+ if (edit.width && p < str + *edit.width) {
+ return false; // unconverted characters remain in fixed width field
}
}
- if (edit.width && p < str + *edit.width) {
- return false; // unconverted characters remain in fixed width field
- }
// Success on the fast path!
*reinterpret_cast<decimal::BinaryFloatingPointNumber<PRECISION> *>(n) =
converted.binary;
@@ -451,7 +518,7 @@ template <int KIND>
bool EditCommonRealInput(IoStatementState &io, const DataEdit &edit, void *n) {
constexpr int binaryPrecision{common::PrecisionOfRealKind(KIND)};
if (TryFastPathRealInput<binaryPrecision>(io, edit, n)) {
- return true;
+ return CheckCompleteListDirectedField(io, edit);
}
// Fast path wasn't available or didn't work; go the more general route
static constexpr int maxDigits{
@@ -465,7 +532,11 @@ bool EditCommonRealInput(IoStatementState &io, const DataEdit &edit, void *n) {
return false;
}
if (got == 0) {
- io.GetIoErrorHandler().SignalError(IostatBadRealInput);
+ const auto &connection{io.GetConnectionState()};
+ io.GetIoErrorHandler().SignalError(IostatBadRealInput,
+ "Bad real input data at column %d of record %d",
+ static_cast<int>(connection.positionInRecord + 1),
+ static_cast<int>(connection.currentRecordNumber));
return false;
}
bool hadExtra{got > maxDigits};
@@ -512,7 +583,11 @@ bool EditCommonRealInput(IoStatementState &io, const DataEdit &edit, void *n) {
converted.flags | decimal::Inexact);
}
if (*p) { // unprocessed junk after value
- io.GetIoErrorHandler().SignalError(IostatBadRealInput);
+ const auto &connection{io.GetConnectionState()};
+ io.GetIoErrorHandler().SignalError(IostatBadRealInput,
+ "Trailing characters after real input data at column %d of record %d",
+ static_cast<int>(connection.positionInRecord + 1),
+ static_cast<int>(connection.currentRecordNumber));
return false;
}
*reinterpret_cast<decimal::BinaryFloatingPointNumber<binaryPrecision> *>(n) =
@@ -525,7 +600,7 @@ bool EditCommonRealInput(IoStatementState &io, const DataEdit &edit, void *n) {
}
RaiseFPExceptions(converted.flags);
}
- return true;
+ return CheckCompleteListDirectedField(io, edit);
}
template <int KIND>
@@ -602,13 +677,13 @@ bool EditLogicalInput(IoStatementState &io, const DataEdit &edit, bool &x) {
"Bad character '%lc' in LOGICAL input field", *next);
return false;
}
- if (remaining) { // ignore the rest of the field
+ if (remaining) { // ignore the rest of a fixed-width field
io.HandleRelativePosition(*remaining);
} else if (edit.descriptor == DataEdit::ListDirected) {
while (io.NextInField(remaining, edit)) { // discard rest of field
}
}
- return true;
+ return CheckCompleteListDirectedField(io, edit);
}
// See 13.10.3.1 paragraphs 7-9 in Fortran 2018
@@ -800,7 +875,7 @@ bool EditCharacterInput(
}
// Pad the remainder of the input variable, if any.
std::fill_n(x, length, ' ');
- return true;
+ return CheckCompleteListDirectedField(io, edit);
}
template bool EditRealInput<2>(IoStatementState &, const DataEdit &, void *);
diff --git a/flang/runtime/iostat.cpp b/flang/runtime/iostat.cpp
index d786e505433f8ec..cc5641693a078a6 100644
--- a/flang/runtime/iostat.cpp
+++ b/flang/runtime/iostat.cpp
@@ -113,6 +113,8 @@ const char *IostatErrorString(int iostat) {
return "Impermissible I/O statement on child I/O unit";
case IostatBadNewUnit:
return "NEWUNIT= without FILE= or STATUS='SCRATCH'";
+ case IostatBadListDirectedInputSeparator:
+ return "List-directed input value has trailing unused characters";
default:
return nullptr;
}
</pre>
</details>
https://github.com/llvm/llvm-project/pull/66244
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