Diff: ConfigFile.cpp

Revision:

0:57f3e167586f

Child:

1:a802df951169

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/ConfigFile.cpp	Thu Jan 27 21:08:51 2011 +0000
@@ -0,0 +1,150 @@
+/*
+ * ConfigFile.cpp
+ * Simple Config file reader class
+ *
+ * Copyright (c) 2011 Peter Brier
+ *
+ *   This file is part of the LaOS project (see: http://wiki.protospace.nl/index.php/LaOS)
+ *
+ *   LaOS is free software: you can redistribute it and/or modify
+ *   it under the terms of the GNU General Public License as published by
+ *   the Free Software Foundation, either version 3 of the License, or
+ *   (at your option) any later version.
+ *
+ *   LaOS is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ *
+ *   You should have received a copy of the GNU General Public License
+ *   along with LaOS.  If not, see <http://www.gnu.org/licenses/>.
+ * 
+ */
+#include "ConfigFile.h"
+
+/// Make new config file object
+/** Open config file. 
+  * Note: the file handle is kept open during the lifetime of this object. 
+  * To close the file: destroy this ConfigFile object!
+  * @param file Filename of the configuration file.
+  */ 
+ConfigFile::ConfigFile(char *file) 
+{
+ // printf("ConfigFile(%s)\n\r", file);
+  fp = fopen(file,"rb");
+}
+
+ /**
+   * Destroy a config file (closes the file handle)
+   */
+ConfigFile::~ConfigFile() 
+{
+ // printf("~ConfigFile()\n\r");
+  if ( fp != NULL )
+    fclose(fp);
+}
+
+/** Read value. If file is not open, or key does not exist: copy default value (return false)
+  * @param key name of the key in the file
+  * @param value pointer to buffer that receives the value
+  * @param maxlen the maximum length of the value. If the actual value is longer, it is truncated
+  * @param def Default value. If the key is not found in the file, this value is copied. 
+  * @return "true" if the key is found "false" is key is not found (default value is returned)
+  */ 
+bool ConfigFile::Value(char *key, char *value,  size_t maxlen, char *def)
+{
+  int m=0,n=0,c,s=0;
+  if (fp == NULL)
+  {
+    strncpy(value, def, maxlen);
+    return false;
+  }
+  // printf("Value()\n\r");
+  n = strlen(key);
+  fseek(fp, 0L, SEEK_SET);
+  while( s != 99  ) 
+  {
+    c = fgetc(fp);
+    if ( c == EOF ) 
+      break;
+   // printf("%d: '%c'\n\r", s, c);
+    switch( s  )// sate machine
+    { 
+      case 0: // (re) start: note: no break; fall through to case 1
+        m=0; 
+        s=1;
+      case 1: // read key, skip spaces
+        if ( c == key[m] ) 
+          m++; 
+        else 
+          s = 0;
+        if ( c == ';' ) 
+          s = 10; 
+        else if ( c == ' ' || c == '\t' || c == '\n' || c == '\r') 
+        {
+          if ( n == m ) // key found
+          {
+            s = 2;
+            m = 0; 
+          }
+          else
+            s = 0;
+        }
+        break;
+      case 2: // key matched, skip whitepaces upto the first char
+        if ( c == ';' ) s = 99;
+        else if ( c != ' ' && c != '\t' ) 
+        { 
+          s = 3;
+          m = 1;
+          if ( m < maxlen) 
+            *value++ = c;
+        }
+        break;
+        
+      case 3: // copy value content, upto eol or comment
+        if ( m == maxlen || c == '\n' || c == '\r' || c == ';' ) 
+          s = 99;
+        else
+        {
+          m++;
+          *value++ = c;
+        }
+        break;         
+      case 10: // skip comments, upto eol or eof
+        if ( c == '\n' || c == '\r' ) s = 0;
+        break;
+     }
+  }
+  if ( s == 99 && m > 1) // key found, and value assigned
+  {
+     *value = 0; // terminate string
+    return true; 
+  }
+  else
+  {
+    strncpy(value, def, maxlen);
+    return false;
+  } 
+}
+
+
+/** Read Integer value. If file is not open, or key does not exist: copy default value (return false)
+  * @param key name of the key in the file
+  * @param value pointer to integer that receives the value
+  * @param def Default value. If the key is not found in the file, this value is copied. 
+  * @return "true" if the key is found "false" is key is not found (default value is returned)
+  */ 
+// Return int value
+bool ConfigFile::Value(char *key, int *value, int def)
+{
+  char val[16];
+  bool b = Value(key, val, 15, "");
+  if ( b )
+    *value = atoi(val);
+  else
+  {
+     *value = def;
+  }
+  return b;
+}