cmStringAlgorithms: Add cmCatViews and cmStrCat functions

1 files changed, 73 insertions, 0 deletions

diff --git a/Source/cmStringAlgorithms.cxx b/Source/cmStringAlgorithms.cxx
new file mode 100644
index 0000000000..5deb9b078d
--- /dev/null
+++ b/Source/cmStringAlgorithms.cxx
@@ -0,0 +1,73 @@
+/* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
+   file Copyright.txt or https://cmake.org/licensing for details.  */
+#include "cmStringAlgorithms.h"
+
+#include <algorithm>
+#include <cstdio>
+
+namespace {
+template <std::size_t N, typename T>
+inline void MakeDigits(cm::string_view& view, char (&digits)[N],
+                       const char* pattern, T value)
+{
+  int res = std::snprintf(digits, N, pattern, value);
+  if (res > 0 && res < static_cast<int>(N)) {
+    view = cm::string_view(digits, static_cast<std::size_t>(res));
+  }
+}
+} // unnamed namespace
+
+cmAlphaNum::cmAlphaNum(int val)
+{
+  MakeDigits(View_, Digits_, "%i", val);
+}
+
+cmAlphaNum::cmAlphaNum(unsigned int val)
+{
+  MakeDigits(View_, Digits_, "%u", val);
+}
+
+cmAlphaNum::cmAlphaNum(long int val)
+{
+  MakeDigits(View_, Digits_, "%li", val);
+}
+
+cmAlphaNum::cmAlphaNum(unsigned long int val)
+{
+  MakeDigits(View_, Digits_, "%lu", val);
+}
+
+cmAlphaNum::cmAlphaNum(long long int val)
+{
+  MakeDigits(View_, Digits_, "%lli", val);
+}
+
+cmAlphaNum::cmAlphaNum(unsigned long long int val)
+{
+  MakeDigits(View_, Digits_, "%llu", val);
+}
+
+cmAlphaNum::cmAlphaNum(float val)
+{
+  MakeDigits(View_, Digits_, "%g", static_cast<double>(val));
+}
+
+cmAlphaNum::cmAlphaNum(double val)
+{
+  MakeDigits(View_, Digits_, "%g", val);
+}
+
+std::string cmCatViews(std::initializer_list<cm::string_view> views)
+{
+  std::size_t total_size = 0;
+  for (cm::string_view const& view : views) {
+    total_size += view.size();
+  }
+
+  std::string result(total_size, '\0');
+  std::string::iterator sit = result.begin();
+  for (cm::string_view const& view : views) {
+    sit = std::copy_n(view.data(), view.size(), sit);
+  }
+  return result;
+}