Add safe_strtou32, safe_strtou64, and safe_strtod to numbers.h.

Change: 119099796

3 files changed, 169 insertions, 8 deletions

diff --git a/tensorflow/core/lib/strings/numbers.cc b/tensorflow/core/lib/strings/numbers.cc
index 9e3a6d5458..38a4b6698b 100644
--- a/tensorflow/core/lib/strings/numbers.cc
+++ b/tensorflow/core/lib/strings/numbers.cc
@@ -108,11 +108,13 @@ char SafeFirstChar(StringPiece str) {
   if (str.empty()) return '\0';
   return str[0];
 }
+void SkipSpaces(StringPiece* str) {
+  while (isspace(SafeFirstChar(*str))) str->remove_prefix(1);
+}
 }  // namespace
 
 bool safe_strto64(StringPiece str, int64* value) {
-  // Skip leading space.
-  while (isspace(SafeFirstChar(str))) str.remove_prefix(1);
+  SkipSpaces(&str);
 
   int64 vlimit = kint64max;
   int sign = 1;
@@ -145,9 +147,28 @@ bool safe_strto64(StringPiece str, int64* value) {
     } while (isdigit(SafeFirstChar(str)));
   }
 
-  // Skip trailing space.
-  while (isspace(SafeFirstChar(str))) str.remove_prefix(1);
+  SkipSpaces(&str);
+  if (!str.empty()) return false;
+
+  *value = result;
+  return true;
+}
+
+bool safe_strtou64(StringPiece str, uint64* value) {
+  SkipSpaces(&str);
+  if (!isdigit(SafeFirstChar(str))) return false;
+
+  int64 result = 0;
+  do {
+    int digit = SafeFirstChar(str) - '0';
+    if ((kuint64max - digit) / 10 < result) {
+      return false;
+    }
+    result = result * 10 + digit;
+    str.remove_prefix(1);
+  } while (isdigit(SafeFirstChar(str)));
 
+  SkipSpaces(&str);
   if (!str.empty()) return false;
 
   *value = result;
@@ -155,8 +176,7 @@ bool safe_strto64(StringPiece str, int64* value) {
 }
 
 bool safe_strto32(StringPiece str, int32* value) {
-  // Skip leading space.
-  while (isspace(SafeFirstChar(str))) str.remove_prefix(1);
+  SkipSpaces(&str);
 
   int64 vmax = kint32max;
   int sign = 1;
@@ -177,8 +197,7 @@ bool safe_strto32(StringPiece str, int32* value) {
     str.remove_prefix(1);
   } while (isdigit(SafeFirstChar(str)));
 
-  // Skip trailing space.
-  while (isspace(SafeFirstChar(str))) str.remove_prefix(1);
+  SkipSpaces(&str);
 
   if (!str.empty()) return false;
 
@@ -186,6 +205,26 @@ bool safe_strto32(StringPiece str, int32* value) {
   return true;
 }
 
+bool safe_strtou32(StringPiece str, uint32* value) {
+  SkipSpaces(&str);
+  if (!isdigit(SafeFirstChar(str))) return false;
+
+  int64 result = 0;
+  do {
+    result = result * 10 + SafeFirstChar(str) - '0';
+    if (result > kuint32max) {
+      return false;
+    }
+    str.remove_prefix(1);
+  } while (isdigit(SafeFirstChar(str)));
+
+  SkipSpaces(&str);
+  if (!str.empty()) return false;
+
+  *value = result;
+  return true;
+}
+
 bool safe_strtof(const char* str, float* value) {
   char* endptr;
   *value = strtof(str, &endptr);
@@ -197,6 +236,17 @@ bool safe_strtof(const char* str, float* value) {
   return *str != '\0' && *endptr == '\0';
 }
 
+bool safe_strtod(const char* str, double* value) {
+  char* endptr;
+  *value = strtod(str, &endptr);
+  while (isspace(*endptr)) ++endptr;
+  // Ignore range errors from strtod/strtof.
+  // The values it returns on underflow and
+  // overflow are the right fallback in a
+  // robust setting.
+  return *str != '\0' && *endptr == '\0';
+}
+
 char* FloatToBuffer(float value, char* buffer) {
   // FLT_DIG is 6 for IEEE-754 floats, which are used on almost all
   // platforms these days.  Just in case some system exists where FLT_DIG
diff --git a/tensorflow/core/lib/strings/numbers.h b/tensorflow/core/lib/strings/numbers.h
index 68ddc68ebb..69a9a78fde 100644
--- a/tensorflow/core/lib/strings/numbers.h
+++ b/tensorflow/core/lib/strings/numbers.h
@@ -97,16 +97,31 @@ bool HexStringToUint64(const StringPiece& s, uint64* v);
 // Return false with overflow or invalid input.
 bool safe_strto32(StringPiece str, int32* value);
 
+// Convert strings to unsigned 32bit integer values.
+// Leading and trailing spaces are allowed.
+// Return false with overflow or invalid input.
+bool safe_strtou32(StringPiece str, uint32* value);
+
 // Convert strings to 64bit integer values.
 // Leading and trailing spaces are allowed.
 // Return false with overflow or invalid input.
 bool safe_strto64(StringPiece str, int64* value);
 
+// Convert strings to unsigned 64bit integer values.
+// Leading and trailing spaces are allowed.
+// Return false with overflow or invalid input.
+bool safe_strtou64(StringPiece str, uint64* value);
+
 // Convert strings to floating point values.
 // Leading and trailing spaces are allowed.
 // Values may be rounded on over- and underflow.
 bool safe_strtof(const char* str, float* value);
 
+// Convert strings to double precision floating point values.
+// Leading and trailing spaces are allowed.
+// Values may be rounded on over- and underflow.
+bool safe_strtod(const char* str, double* value);
+
 // Converts from an int64 representing a number of bytes to a
 // human readable string representing the same number.
 // e.g. 12345678 -> "11.77MiB".
diff --git a/tensorflow/core/lib/strings/numbers_test.cc b/tensorflow/core/lib/strings/numbers_test.cc
index 88acd57852..52b77ac2f9 100644
--- a/tensorflow/core/lib/strings/numbers_test.cc
+++ b/tensorflow/core/lib/strings/numbers_test.cc
@@ -119,6 +119,39 @@ TEST(safe_strto32, Int32s) {
   EXPECT_EQ(false, safe_strto32(StringPiece(nullptr, 0), &result));
 }
 
+TEST(safe_strtou32, UInt32s) {
+  uint32 result;
+
+  EXPECT_TRUE(safe_strtou32("0", &result));
+  EXPECT_EQ(0, result);
+  EXPECT_TRUE(safe_strtou32("1", &result));
+  EXPECT_EQ(1, result);
+  EXPECT_TRUE(safe_strtou32("123", &result));
+  EXPECT_EQ(123, result);
+  EXPECT_TRUE(safe_strtou32("4294967295", &result));
+  EXPECT_EQ(4294967295, result);
+
+  // Invalid argument
+  EXPECT_FALSE(safe_strtou32(" 132as ", &result));
+  EXPECT_FALSE(safe_strtou32(" 132.2 ", &result));
+  EXPECT_FALSE(safe_strtou32(" -", &result));
+  EXPECT_FALSE(safe_strtou32("", &result));
+  EXPECT_FALSE(safe_strtou32("  ", &result));
+  EXPECT_FALSE(safe_strtou32("123 a", &result));
+  EXPECT_FALSE(safe_strtou32("123 456", &result));
+
+  // Overflow
+  EXPECT_FALSE(safe_strtou32("4294967296", &result));
+  EXPECT_FALSE(safe_strtou32("-1", &result));
+
+  // Check that the StringPiece's length is respected.
+  EXPECT_TRUE(safe_strtou32(StringPiece("123", 1), &result));
+  EXPECT_EQ(1, result);
+  EXPECT_TRUE(safe_strtou32(StringPiece(" 123", 3), &result));
+  EXPECT_EQ(12, result);
+  EXPECT_FALSE(safe_strtou32(StringPiece(nullptr, 0), &result));
+}
+
 TEST(safe_strto64, Int64s) {
   int64 result;
 
@@ -155,5 +188,68 @@ TEST(safe_strto64, Int64s) {
   EXPECT_EQ(false, safe_strto64(StringPiece(nullptr, 0), &result));
 }
 
+TEST(safe_strtou64, UInt64s) {
+  uint64 result;
+
+  EXPECT_TRUE(safe_strtou64("0", &result));
+  EXPECT_EQ(0, result);
+  EXPECT_TRUE(safe_strtou64("1", &result));
+  EXPECT_EQ(1, result);
+  EXPECT_TRUE(safe_strtou64("123", &result));
+  EXPECT_EQ(123, result);
+  EXPECT_TRUE(safe_strtou64("  345  ", &result));
+  EXPECT_EQ(345, result);
+  EXPECT_TRUE(safe_strtou64("18446744073709551615", &result));
+  EXPECT_EQ(18446744073709551615UL, result);
+
+  // Invalid argument
+  EXPECT_FALSE(safe_strtou64(" 132.2 ", &result));
+  EXPECT_FALSE(safe_strtou64(" 132.2 ", &result));
+  EXPECT_FALSE(safe_strtou64(" -", &result));
+  EXPECT_FALSE(safe_strtou64("", &result));
+  EXPECT_FALSE(safe_strtou64("  ", &result));
+  EXPECT_FALSE(safe_strtou64("123 a", &result));
+  EXPECT_FALSE(safe_strtou64("123 456", &result));
+
+  // Overflow
+  EXPECT_FALSE(safe_strtou64("18446744073709551616", &result));
+  EXPECT_FALSE(safe_strtou64("-1", &result));
+
+  // Check that the StringPiece's length is respected.
+  EXPECT_TRUE(safe_strtou64(StringPiece("123", 1), &result));
+  EXPECT_EQ(1, result);
+  EXPECT_TRUE(safe_strtou64(StringPiece(" 123", 3), &result));
+  EXPECT_EQ(12, result);
+  EXPECT_FALSE(safe_strtou64(StringPiece(nullptr, 0), &result));
+}
+
+TEST(safe_strtof, Float) {
+  float result = 0;
+
+  EXPECT_TRUE(safe_strtof("0.123456", &result));
+  EXPECT_EQ(0.123456f, result);
+  EXPECT_FALSE(safe_strtof("0.12345abc", &result));
+
+  // Overflow to infinity, underflow to 0.
+  EXPECT_TRUE(safe_strtof("1e39", &result));
+  EXPECT_EQ(std::numeric_limits<float>::infinity(), result);
+  EXPECT_TRUE(safe_strtof("1e-50", &result));
+  EXPECT_EQ(0, result);
+}
+
+TEST(safe_strtod, Double) {
+  double result = 0;
+
+  EXPECT_TRUE(safe_strtod("0.1234567890123", &result));
+  EXPECT_EQ(0.1234567890123, result);
+  EXPECT_FALSE(safe_strtod("0.1234567890123abc", &result));
+
+  // Overflow to infinity, underflow to 0.
+  EXPECT_TRUE(safe_strtod("1e310", &result));
+  EXPECT_EQ(std::numeric_limits<double>::infinity(), result);
+  EXPECT_TRUE(safe_strtod("1e-325", &result));
+  EXPECT_EQ(0, result);
+}
+
 }  // namespace strings
 }  // namespace tensorflow