More test on object parsing

src/Internals/QuotedString.cpp

@@ -0,0 +1,119 @@
+/*
+ * Arduino JSON library
+ * Benoit Blanchon 2014 - MIT License
+ */
+
+#include "ArduinoJson/Internals/QuotedString.hpp"
+
+using namespace ArduinoJson::Internals;
+
+static inline char getSpecialChar(char c)
+{
+    // Optimized for code size on a 8-bit AVR
+
+    const char* p = "\"\"\\\\\bb\ff\nn\rr\tt\0";
+
+    while (p[0] && p[0] != c)
+    {
+        p += 2;
+    }
+
+    return p[1];
+}
+
+static inline size_t printCharTo(char c, Print* p)
+{
+    char specialChar = getSpecialChar(c);
+
+    return specialChar != 0
+        ? p->write('\\') + p->write(specialChar)
+        : p->write(c);
+}
+
+size_t QuotedString::printTo(const char* s, Print* p)
+{
+    if (!s) return p->print("null");
+    
+    size_t n = p->write('\"');
+
+    while (*s)
+    {
+        n += printCharTo(*s++, p);
+    }
+
+    return n + p->write('\"');
+}
+
+static char unescapeChar(char c)
+{
+    // Optimized for code size on a 8-bit AVR
+
+    const char* p = "b\bf\fn\nr\rt\t";
+
+    while (true)
+    {
+        if (p[0] == 0) return c;
+        if (p[0] == c) return p[1];
+        p += 2;
+    }
+}
+
+static inline bool isQuote(char c)
+{
+    return c == '\"' || c == '\'';
+}
+
+char* QuotedString::extractFrom(char* input, char** endPtr)
+{
+    char firstChar = *input;
+    char stopChar;
+    char* startPtr;
+
+    if (isQuote(firstChar))
+    {
+        stopChar = firstChar; // closing quote is the same as opening quote
+        startPtr = input + 1; // skip the quote
+    }
+    else
+    {
+        stopChar = ':'; // assume we're parsing a key in an object
+        startPtr = input; // no quote to skip
+    }
+
+    char* readPtr = startPtr;
+    char* writePtr = startPtr;
+    char c;
+
+    for (;;)
+    {
+        c = *readPtr++;
+
+        if (c == 0)
+        {
+            // premature ending
+            return 0;
+        }
+
+        if (c == stopChar)
+        {
+            // closing quote
+            break;
+        }
+
+        if (c == '\\')
+        {
+            // replace char
+            c = unescapeChar(*readPtr++);
+        }
+
+        *writePtr++ = c;
+    }
+
+    // end the string here
+    *writePtr = 0;
+
+    // update end ptr
+    *endPtr = readPtr;
+
+    return startPtr;
+}