Fix "unsafe narrowing" warnings in absl, 5/n.

Addresses failures with the following, in some files:
-Wshorten-64-to-32
-Wimplicit-int-conversion
-Wsign-compare
-Wsign-conversion
-Wtautological-unsigned-zero-compare

(This specific CL focuses on .cc files in strings/internal/.)

Bug: chromium:1292951
PiperOrigin-RevId: 468215101
Change-Id: I07fa487bcf2cf62d403489c3be7a5997cdef8987

1 files changed, 19 insertions, 16 deletions

diff --git a/absl/strings/internal/str_format/arg.cc b/absl/strings/internal/str_format/arg.cc
index 02aeeebe..007e8e83 100644
--- a/absl/strings/internal/str_format/arg.cc
+++ b/absl/strings/internal/str_format/arg.cc
@@ -77,7 +77,7 @@ class IntDigits {
       v >>= 3;
     } while (v);
     start_ = p;
-    size_ = storage_ + sizeof(storage_) - p;
+    size_ = static_cast<size_t>(storage_ + sizeof(storage_) - p);
   }
 
   // Print the signed or unsigned integer as decimal.
@@ -86,7 +86,8 @@ class IntDigits {
   void PrintAsDec(T v) {
     static_assert(std::is_integral<T>::value, "");
     start_ = storage_;
-    size_ = numbers_internal::FastIntToBuffer(v, storage_) - storage_;
+    size_ = static_cast<size_t>(numbers_internal::FastIntToBuffer(v, storage_) -
+                                storage_);
   }
 
   void PrintAsDec(int128 v) {
@@ -115,7 +116,7 @@ class IntDigits {
     if (add_neg) {
       *--p = '-';
     }
-    size_ = storage_ + sizeof(storage_) - p;
+    size_ = static_cast<size_t>(storage_ + sizeof(storage_) - p);
     start_ = p;
   }
 
@@ -138,7 +139,7 @@ class IntDigits {
       ++p;
     }
     start_ = p;
-    size_ = storage_ + sizeof(storage_) - p;
+    size_ = static_cast<size_t>(storage_ + sizeof(storage_) - p);
   }
 
   // Print the unsigned integer as hex using uppercase.
@@ -154,7 +155,7 @@ class IntDigits {
       v >>= 4;
     } while (v);
     start_ = p;
-    size_ = storage_ + sizeof(storage_) - p;
+    size_ = static_cast<size_t>(storage_ + sizeof(storage_) - p);
   }
 
   // The printed value including the '-' sign if available.
@@ -208,10 +209,12 @@ string_view SignColumn(bool neg, const FormatConversionSpecImpl conv) {
   return {};
 }
 
-bool ConvertCharImpl(unsigned char v, const FormatConversionSpecImpl conv,
-                     FormatSinkImpl *sink) {
+bool ConvertCharImpl(char v,
+                     const FormatConversionSpecImpl conv,
+                     FormatSinkImpl* sink) {
   size_t fill = 0;
-  if (conv.width() >= 0) fill = conv.width();
+  if (conv.width() >= 0)
+    fill = static_cast<size_t>(conv.width());
   ReducePadding(1, &fill);
   if (!conv.has_left_flag()) sink->Append(fill, ' ');
   sink->Append(1, v);
@@ -225,7 +228,8 @@ bool ConvertIntImplInnerSlow(const IntDigits &as_digits,
   // Print as a sequence of Substrings:
   //   [left_spaces][sign][base_indicator][zeroes][formatted][right_spaces]
   size_t fill = 0;
-  if (conv.width() >= 0) fill = conv.width();
+  if (conv.width() >= 0)
+    fill = static_cast<size_t>(conv.width());
 
   string_view formatted = as_digits.without_neg_or_zero();
   ReducePadding(formatted, &fill);
@@ -236,10 +240,9 @@ bool ConvertIntImplInnerSlow(const IntDigits &as_digits,
   string_view base_indicator = BaseIndicator(as_digits, conv);
   ReducePadding(base_indicator, &fill);
 
-  int precision = conv.precision();
-  bool precision_specified = precision >= 0;
-  if (!precision_specified)
-    precision = 1;
+  bool precision_specified = conv.precision() >= 0;
+  size_t precision =
+      precision_specified ? static_cast<size_t>(conv.precision()) : size_t{1};
 
   if (conv.has_alt_flag() &&
       conv.conversion_char() == FormatConversionCharInternal::o) {
@@ -247,7 +250,7 @@ bool ConvertIntImplInnerSlow(const IntDigits &as_digits,
     //   "For o conversion, it increases the precision (if necessary) to
     //   force the first digit of the result to be zero."
     if (formatted.empty() || *formatted.begin() != '0') {
-      int needed = static_cast<int>(formatted.size()) + 1;
+      size_t needed = formatted.size() + 1;
       precision = std::max(precision, needed);
     }
   }
@@ -287,7 +290,7 @@ bool ConvertIntArg(T v, const FormatConversionSpecImpl conv,
   // FormatConversionChar is declared, but not defined.
   switch (static_cast<uint8_t>(conv.conversion_char())) {
     case static_cast<uint8_t>(FormatConversionCharInternal::c):
-      return ConvertCharImpl(static_cast<unsigned char>(v), conv, sink);
+      return ConvertCharImpl(static_cast<char>(v), conv, sink);
 
     case static_cast<uint8_t>(FormatConversionCharInternal::o):
       as_digits.PrintAsOct(static_cast<U>(v));
@@ -375,7 +378,7 @@ FormatConvertImpl(const char *v, const FormatConversionSpecImpl conv,
     len = std::strlen(v);
   } else {
     // If precision is set, we look for the NUL-terminator on the valid range.
-    len = std::find(v, v + conv.precision(), '\0') - v;
+    len = static_cast<size_t>(std::find(v, v + conv.precision(), '\0') - v);
   }
   return {ConvertStringArg(string_view(v, len), conv, sink)};
 }