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-rw-r--r--lib/antlr/src/ANTLRUtil.cpp163
1 files changed, 163 insertions, 0 deletions
diff --git a/lib/antlr/src/ANTLRUtil.cpp b/lib/antlr/src/ANTLRUtil.cpp
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+++ b/lib/antlr/src/ANTLRUtil.cpp
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+/* ANTLR Translator Generator
+ * Project led by Terence Parr at http://www.jGuru.com
+ * Software rights: http://www.antlr.org/license.html
+ *
+ * $Id$
+ */
+
+#include <antlr/config.hpp>
+#include <antlr/IOException.hpp>
+
+#include <iostream>
+#include <cctype>
+#include <string>
+
+#ifdef ANTLR_CXX_SUPPORTS_NAMESPACE
+namespace antlr {
+#endif
+
+/** Eat whitespace from the input stream
+ * @param is the stream to read from
+ */
+ANTLR_USE_NAMESPACE(std)istream& eatwhite( ANTLR_USE_NAMESPACE(std)istream& is )
+{
+ char c;
+ while( is.get(c) )
+ {
+#ifdef ANTLR_CCTYPE_NEEDS_STD
+ if( !ANTLR_USE_NAMESPACE(std)isspace(c) )
+#else
+ if( !isspace(c) )
+#endif
+ {
+ is.putback(c);
+ break;
+ }
+ }
+ return is;
+}
+
+/** Read a string enclosed by '"' from a stream. Also handles escaping of \".
+ * Skips leading whitespace.
+ * @param in the istream to read from.
+ * @returns the string read from file exclusive the '"'
+ * @throws IOException if string is badly formatted
+ */
+ANTLR_USE_NAMESPACE(std)string read_string( ANTLR_USE_NAMESPACE(std)istream& in )
+{
+ char ch;
+ ANTLR_USE_NAMESPACE(std)string ret("");
+ // States for a simple state machine...
+ enum { START, READING, ESCAPE, FINISHED };
+ int state = START;
+
+ eatwhite(in);
+
+ while( state != FINISHED && in.get(ch) )
+ {
+ switch( state )
+ {
+ case START:
+ // start state: check wether starting with " then switch to READING
+ if( ch != '"' )
+ throw IOException("string must start with '\"'");
+ state = READING;
+ continue;
+ case READING:
+ // reading state: look out for escape sequences and closing "
+ if( ch == '\\' ) // got escape sequence
+ {
+ state = ESCAPE;
+ continue;
+ }
+ if( ch == '"' ) // close quote -> stop
+ {
+ state = FINISHED;
+ continue;
+ }
+ ret += ch; // else append...
+ continue;
+ case ESCAPE:
+ switch(ch)
+ {
+ case '\\':
+ ret += ch;
+ state = READING;
+ continue;
+ case '"':
+ ret += ch;
+ state = READING;
+ continue;
+ case '0':
+ ret += '\0';
+ state = READING;
+ continue;
+ default: // unrecognized escape is not mapped
+ ret += '\\';
+ ret += ch;
+ state = READING;
+ continue;
+ }
+ }
+ }
+ if( state != FINISHED )
+ throw IOException("badly formatted string: "+ret);
+
+ return ret;
+}
+
+/* Read a ([A-Z][0-9][a-z]_)* kindoff thing. Skips leading whitespace.
+ * @param in the istream to read from.
+ */
+ANTLR_USE_NAMESPACE(std)string read_identifier( ANTLR_USE_NAMESPACE(std)istream& in )
+{
+ char ch;
+ ANTLR_USE_NAMESPACE(std)string ret("");
+
+ eatwhite(in);
+
+ while( in.get(ch) )
+ {
+#ifdef ANTLR_CCTYPE_NEEDS_STD
+ if( ANTLR_USE_NAMESPACE(std)isupper(ch) ||
+ ANTLR_USE_NAMESPACE(std)islower(ch) ||
+ ANTLR_USE_NAMESPACE(std)isdigit(ch) ||
+ ch == '_' )
+#else
+ if( isupper(ch) || islower(ch) || isdigit(ch) || ch == '_' )
+#endif
+ ret += ch;
+ else
+ {
+ in.putback(ch);
+ break;
+ }
+ }
+ return ret;
+}
+
+/** Read a attribute="value" thing. Leading whitespace is skipped.
+ * Between attribute and '=' no whitespace is allowed. After the '=' it is
+ * permitted.
+ * @param in the istream to read from.
+ * @param attribute string the attribute name is put in
+ * @param value string the value of the attribute is put in
+ * @throws IOException if something is fishy. E.g. malformed quoting
+ * or missing '='
+ */
+void read_AttributeNValue( ANTLR_USE_NAMESPACE(std)istream& in,
+ ANTLR_USE_NAMESPACE(std)string& attribute,
+ ANTLR_USE_NAMESPACE(std)string& value )
+{
+ attribute = read_identifier(in);
+
+ char ch;
+ if( in.get(ch) && ch == '=' )
+ value = read_string(in);
+ else
+ throw IOException("invalid attribute=value thing "+attribute);
+}
+
+#ifdef ANTLR_CXX_SUPPORTS_NAMESPACE
+}
+#endif