wip: config reader, reading input

[physics.git] / src / config / reader.cpp

diff --git a/src/config/reader.cpp b/src/config/reader.cpp
index ce35ab8..de6da20 100644 (file)
--- a/src/config/reader.cpp
+++ b/src/config/reader.cpp
@@ -30,6 +30,7 @@ char* configDir = "../configs/";
 /// ***** Private Method Headers *****
 
 void processLine(const string& str, keyMap* map);
+bool extractLine(const string& str, string* name, string* value);
 
 /// ***** Private Variables *****
 
@@ -68,5 +69,108 @@ void readConfigs(keyMap* map)
 
 void processLine(const string& str, keyMap* map)
 {
-    cout << str << endl;
+    string name;
+    string value;
+
+    bool extracted;
+
+    extracted = extractLine(str, &name, &value);
+
+    if(extracted)
+    {
+        cout << name << endl;
+        cout << value << endl;
+    }
+}
+
+/*
+ * Return true iff the string str, had a name and value extracted and saved in
+ * name and value. Otherwise return false and leave name and value alone.
+ */
+bool extractLine(const string& str, string* name, string* value)
+{
+    /*
+     * state    := 0 if eating leading name whitespace
+     *          := 1 if saving name
+     *          := 2 if eating trailing name whitespace
+     *          := 3 if eating leading value whitespace
+     *          := 4 if saving value
+     *          := 5 if all is done and well
+     */
+    int state = 0;
+
+    int char_pos = 0;
+
+    int name_start;
+    int name_end;
+
+    int value_start;
+    int value_end;
+
+    const char* c_str = str.c_str();
+
+    while(true)
+    {
+        if(c_str[char_pos] == 0 && state != 4)
+            return false;
+
+        switch (state)
+        {
+            case 0:
+                if(c_str[char_pos] != ' '
+                && c_str[char_pos] != '\t')
+                {
+                    state++;
+                    name_start = char_pos;
+                }
+                break;
+            case 1:
+                if(c_str[char_pos] == ' '
+                || c_str[char_pos] == '\t'
+                || c_str[char_pos] == '=')
+                {
+                    state++;
+                    name_end = char_pos;
+                }
+                if(c_str[char_pos] == '=')
+                    char_pos--; // decrement to stay on this char
+                break;
+            case 2:
+                if(c_str[char_pos] == '=')
+                {
+                    state++;
+                }
+                break;
+            case 3:
+                if(c_str[char_pos] != ' '
+                && c_str[char_pos] != '\t')
+                {
+                    state++;
+                    value_start = char_pos;
+                }
+                break;
+            case 4:
+                if(c_str[char_pos] == ' '
+                || c_str[char_pos] == '\t'
+                || c_str[char_pos] == 0)
+                {
+                    state++;
+                    value_end = char_pos;
+                }
+                break;
+        }
+
+        if(state == 5)
+            break;
+
+        char_pos++;
+    }
+
+    name->clear();
+    value->clear();
+
+    name->replace(0, 0, c_str, name_start, name_end-name_start);
+    value->replace(0, 0, c_str, value_start, value_end-value_start);
+
+    return true;
 }