Initial commit

1 files changed, 94 insertions, 0 deletions

diff --git a/src/strings.cc b/src/strings.cc
new file mode 100644
index 0000000..1d74dee
--- /dev/null
+++ b/src/strings.cc
@@ -0,0 +1,94 @@
+// -*- mode: c++; c-basic-offset: 2; -*-
+
+#include "common.hh"
+
+#include "character.hh"
+#include "strings.hh"
+
+// static
+void Strings::trim(std::string const& str, size_t* start, size_t* end) {
+  assert(start && end);
+  assert(*start <= *end);
+  assert(*end <= str.size());
+  while (*start < *end && Character::isspace(str, *start)) ++(*start);
+  while (*end > *start && Character::isspace(str, *end - 1)) --(*end);
+}
+
+// static
+std::string Strings::trim(std::string const& str) {
+  return trim(str, 0, str.size());
+}
+
+// static
+std::string Strings::trim(std::string const& str, size_t start, size_t end) {
+  auto s = start, e = end;
+  trim(str, &s, &e);
+  return str.substr(s, e - s);
+}
+
+// static
+std::string Strings::quote(std::string const& str) {
+  return quote(str, 0, str.size());
+}
+
+// static
+std::string Strings::quote(std::string const& str, size_t start, size_t end) {
+  assert(start <= end);
+  assert(end <= str.size());
+  auto i = start;
+  while (i < end) {
+    auto c = str[i];
+    if (c == '"' || c == '\\') break;
+    ++i;
+  }
+  std::string ret("\"");
+  if (i == end) {
+    ret.append(str.substr(start, end - start));
+  } else {
+    ret.append(str.substr(start, i - start));
+    while (true) {
+      ret.push_back('\\');
+      auto j = i++;
+      while (i < end) {
+        auto c = str[i];
+        if (c == '"' || c == '\\') break;
+        ++i;
+      }
+      ret.append(str.substr(j, i - j));
+      if (i == end) break;
+    }
+  }
+  ret.push_back('"');
+  return ret;
+}
+
+// static
+std::string Strings::unquote(std::string const& str) {
+  return unquote(str, 0, str.size());
+}
+
+// static
+std::string Strings::unquote(std::string const& str, size_t start, size_t end) {
+  assert(start < end - 1);
+  assert(end <= str.size());
+  assert(str[start] == '"' && str[end - 1] == '"');
+  ++start;
+  --end;
+  auto i = start;
+  while (i < end && str[i] != '\\') ++i;
+  if (i == end) return str.substr(start, end - start);
+  std::string ret(str.substr(start, i - start));
+  while (true) {
+    ++i;  // skip backslash
+    if (i == end) {
+      assert(false);
+      ret.push_back('\\');
+      break;
+    }
+    auto j = i++;
+    while (i < end && str[i] != '\\') ++i;
+    ret.append(str.substr(j, i - j));
+    if (i == end) break;
+  }
+  return ret;
+}