ParmParse: Option to disable multi-line support

By default, ParmParse supports multi-line values. For example,
```
    plot_vars = dens vx vy vx
                energy entropy
```

This can be disabled by calling setMultiLineSupport(false) before
amrex::Initialize(). This can avoid errors in inputs like,
```
    algo.current_deposition = direct

    # Enable galilean
    psatd.use_default_v_galilean # Unfortunately we forgot = 1
```
With multi-line support, this is unfortunately equivalent to
```
    algo.current_deposition = direct psatd.use_default_v_galilean
```
With multi-line support disabled, it will abort. Note that even
after multi-line support is disabled, one is still allowed to have
```
    f = "x + y
         + sin(z)"
```
because here what's inside the pair of double quotes is considered a single
string.

Src/Base/AMReX_ParmParse.H

@@ -1052,6 +1052,37 @@ public:
  //! Returns [prefix.]* parameters.
  [[nodiscard]] static std::set<std::string> getEntries (const std::string& prefix = std::string());
 
+ /**
+ * \brief Control multi-line support
+ *
+ * By default, ParmParse supports multi-line values. For example,
+ \verbatim
+ plot_vars = dens vx vy vx
+ energy entropy
+ \endverbatim
+ * This can be disabled by calling this function setMultiLineSupport(false)
+ * before amrex::Initialize(). This can avoid errors in inputs like,
+ \verbatim
+ algo.current_deposition = direct
+
+ # Enable galilean
+ psatd.use_default_v_galilean # Unfortunately we forgot = 1
+ \endverbatim
+ * With multi-line support, this is equivalent to
+ \verbatim
+ algo.current_deposition = direct psatd.use_default_v_galilean
+ \endverbatim
+ * With multi-line support disabled, it will abort. Note that after
+ * multi-line support is disabled, one is still allowed to have
+ \verbatim
+ f = "x + y
+ + sin(z)"
+ \endverbatim
+ * because here what's inside the pair of double quotes is considered a
+ * single string.
+ */
+ static void setMultiLineSupport (bool b);
+
  struct PP_entry;
  using Table = std::list<PP_entry>;
  static void appendTable(ParmParse::Table& tab);

Src/Base/AMReX_ParmParse.cpp

@@ -15,6 +15,7 @@
 #include <iostream>
 #include <iterator>
 #include <list>
+#include <numeric>
 #include <regex>
 #include <set>
 #include <sstream>
@@ -33,8 +34,17 @@ static bool finalize_verbose = false;
 static bool finalize_verbose = true;
 #endif
 
+namespace {
+ bool g_multi_line_support = true;
+}
+
 std::string const ParmParse::FileKeyword = "FILE";
 
+void ParmParse::setMultiLineSupport (bool b)
+{
+ g_multi_line_support = b;
+}
+
 //
 // Used by constructor to build table.
 //
@@ -257,9 +267,10 @@ state_name[] =
  "LIST"
 };
 
-void
+int
 eat_garbage (const char*& str)
 {
+ int num_linefeeds = 0;
  for (;;)
  {
  if ( *str == 0 ) break; // NOLINT
@@ -271,31 +282,26 @@ eat_garbage (const char*& str)
  }
  continue;
  }
- else if ( isspace(*str) )
+ else if ( std::isspace(*str) )
  {
+ if (*str == '\n') { ++num_linefeeds; }
  str++;
  }
  else
  {
  break;
  }
  }
+ return num_linefeeds;
 }
 
 PType
-getToken (const char*& str,
- std::string& ostr)
-{
-#define ERROR_MESS \
- amrex::ErrorStream() << "ParmParse::getToken(): invalid string = " << ostr << '\n'; \
- amrex::ErrorStream() << "STATE = " << state_name[state] \
- << ", next char = " << ch << '\n'; \
- amrex::ErrorStream() << ", rest of input = \n" << str << '\n'; \
- amrex::Abort()
+getToken (const char*& str, std::string& ostr, int& num_linefeeds)
+{
  //
  // Eat white space and comments.
  //
- eat_garbage(str);
+ num_linefeeds = eat_garbage(str);
  //
  // Check for end of file.
  //
@@ -343,7 +349,7 @@ getToken (const char*& str,
  str++;
  return pCloseBracket;
  }
- else if ( isalpha(ch) )
+ else if ( std::isalpha(ch) )
  {
  ostr += ch; str++;
  state = IDENTIFIER;
@@ -355,11 +361,11 @@ getToken (const char*& str,
  }
  break;
  case IDENTIFIER:
- if ( isalnum(ch) || ch == '_' || ch == '.' || ch == '[' || ch == ']' || ch == '+' || ch == '-' )
+ if ( std::isalnum(ch) || ch == '_' || ch == '.' || ch == '[' || ch == ']' || ch == '+' || ch == '-' )
  {
  ostr += ch; str++;
  }
- else if ( isspace(ch) || ch == '=' )
+ else if ( std::isspace(ch) || ch == '=' )
  {
  return pDefn;
  }
@@ -388,7 +394,7 @@ getToken (const char*& str,
  }
  break;
  case STRING:
- if ( isspace(ch) || ch == '=' )
+ if ( std::isspace(ch) || ch == '=' )
  {
  return pValue;
  }
@@ -409,10 +415,13 @@ getToken (const char*& str,
  }
  break;
  default:
- ERROR_MESS;
+ amrex::ErrorStream() << "ParmParse::getToken(): invalid string = " << ostr << '\n'
+ << "STATE = " << state_name[state]
+ << ", next char = " << ch << '\n'
+ << ", rest of input = \n" << str << '\n';
+ amrex::Abort();
  }
  }
-#undef ERROR_MESS
 }
 
 
@@ -676,12 +685,14 @@ bldTable (const char*& str,
  std::list<std::string> cur_list;
  ParmParse::Table cur_table;
  std::string tmp_str;
+ std::vector<int> cur_linefeeds;
 
  for (;;)
  {
  std::string tokname;
+ int num_linefeeds;
 
- PType token = getToken(str,tokname);
+ PType token = getToken(str,tokname, num_linefeeds);
 
  switch (token)
  {
@@ -692,6 +703,16 @@ bldTable (const char*& str,
  }
  AMREX_FALLTHROUGH;
  case pEOF:
+ if (! g_multi_line_support &&
+ std::reduce(cur_linefeeds.begin(), cur_linefeeds.end()) > 0)
+ {
+ std::string error_message("ParmParse: Multiple lines in ");
+ error_message.append(cur_name).append(" =");
+ for (auto const& x : cur_list) {
+ error_message.append(" ").append(x);
+ }
+ amrex::Abort(error_message);
+ }
  addDefn(cur_name,cur_list,tab);
  return;
  case pOpenBracket:
@@ -703,6 +724,17 @@ bldTable (const char*& str,
  {
  tmp_str = cur_list.back();
  cur_list.pop_back();
+ cur_linefeeds.pop_back();
+ if (! g_multi_line_support &&
+ std::reduce(cur_linefeeds.begin(), cur_linefeeds.end()) > 0)
+ {
+ std::string error_message("ParmParse: Multiple lines in ");
+ error_message.append(cur_name).append(" =");
+ for (auto const& x : cur_list) {
+ error_message.append(" ").append(x);
+ }
+ amrex::Abort(error_message);
+ }
  addDefn(cur_name, cur_list, tab);
  cur_name = tmp_str;
  }
@@ -716,14 +748,26 @@ bldTable (const char*& str,
  }
  if ( !cur_list.empty() )
  {
+ //
+ // Read one too far, remove last name on list.
+ //
  tmp_str = cur_list.back();
  cur_list.pop_back();
+ cur_linefeeds.pop_back();
+ if (! g_multi_line_support &&
+ std::reduce(cur_linefeeds.begin(), cur_linefeeds.end()) > 0)
+ {
+ std::string error_message("ParmParse: Multiple lines in ");
+ error_message.append(cur_name).append(" =");
+ for (auto const& x : cur_list) {
+ error_message.append(" ").append(x);
+ }
+ amrex::Abort(error_message);
+ }
  addDefn(cur_name,cur_list,tab);
  cur_name = tmp_str;
  }
- //
- // Read one too far, remove last name on list.
- //
+ cur_linefeeds.clear();
  break;
  case pDefn:
  if ( cur_name.empty() )
@@ -743,6 +787,7 @@ bldTable (const char*& str,
  amrex::Abort(msg.c_str());
  }
  cur_list.push_back(tokname);
+ cur_linefeeds.push_back(num_linefeeds);
  break;
  }
  }