Added parser for command line parsing of a BACnet BitString. This is nice if you want to write Event Enable, for example. Expects the ASCII bits as "1011001" or "1,0,1,1,0,0,1" or "1 0 1 1 0 0 1".

bacnet-stack/src/bacapp.c

@@ -1467,9 +1467,9 @@ bool bacapp_parse_application_data(
                     (char *) argv);
                 break;
             case BACNET_APPLICATION_TAG_BIT_STRING:
-                /* FIXME: how to parse a bit string? */
-                status = false;
-                bitstring_init(&value->type.Bit_String);
+#if PRINT_ENABLED
+                status = bitstring_init_ascii(&value->type.Bit_String, argv);
+#endif
                 break;
             case BACNET_APPLICATION_TAG_ENUMERATED:
                 unsigned_long_value = strtoul(argv, NULL, 0);

bacnet-stack/src/bacstr.c

@@ -230,6 +230,53 @@ bool bitstring_same(
     return false;
 }
 
+#if PRINT_ENABLED
+/* converts an null terminated ASCII string to an bitstring.
+   Expects "1,0,1,0,1,1" or "101011" as the bits
+   returns true if successfully converted and fits; false if too long */
+bool bitstring_init_ascii(
+    BACNET_BIT_STRING * bit_string,
+    const char *ascii)
+{
+    bool status = false;        /* return value */
+    unsigned index = 0; /* offset into buffer */
+    uint8_t bit_number = 0;
+
+    if (bit_string) {
+        bitstring_init(bit_string);
+        if (ascii[0] == 0) {
+            /* nothing to decode, so success! */
+            status = true;
+        } else {
+            while (ascii[index] != 0) {
+                if (bit_number > bitstring_bits_capacity(bit_string)) {
+                    /* too long of a string */
+                    status = false;
+                    break;
+                }
+                if (ascii[index] == '1') {
+                    bitstring_set_bit(bit_string, bit_number, true);
+                    bit_number++;
+                    status = true;
+                } else if (ascii[index] == '0') {
+                    bitstring_set_bit(bit_string, bit_number, false);
+                    bit_number++;
+                    status = true;
+                } else {
+                    /* skip non-numeric or alpha */
+                    index++;
+                    continue;
+                }
+                /* next character */
+                index++;
+            }
+        }
+    }
+
+    return status;
+}
+#endif
+
 #define CHARACTER_STRING_CAPACITY (MAX_CHARACTER_STRING_BYTES - 1)
 /* returns false if the string exceeds capacity
    initialize by using value=NULL */