jonmarkgo/ArduinoPusherClient — pull request #1 by lonnon (2012-09-06 18:10:48+00:00)
Title: Escape SSID, passphrase

The WiFly commands for setting SSID and passphrase (`set wlan ssid
` and `set wlan phrase `, respectively) use a dollar
sign ($) in place of the space character, presumably to work around
limitations in its command parser. Most code I've seen that uses the
WiFly RN-XV library works around this limitation simply by inserting
dollar signs into the string that makes up the SSID and passphrase:

const char mySSID[] = "here$be$spaces";
const char myPassword[] = "and$here$be$more";

This works fine for the password, because the only WiFly command that
uses it is `set wlan phrase `. However, the SSID is used
in two places in the various WiFly::join methods, once for setting the
SSID (`set wlan ssid `) and once for joining the wireless network
(`join `). The `join ` command does *not* use dollar signs
as space replacements; in fact, it expects to see space characters, and
using dollar signs results in a failed connection to a network whose
SSID contains spaces.

Long story short, this commit works around the problem by replacing
spaces with dollar signs where appropriate (when calling `set wlan ssid`
and `set wlan phrase`), but passes the SSID intact to the `join`
command. This means that code using the WiFly library can declare SSID
and passphrase strings in a more readable fashion:

const char mySSID[] = "here be spaces";
const char myPassword[] = "and here be more";

One caveat: if the passphrase actually contains dollar signs, this code
will fail to connect, because it will replace them with spaces. However,
the same thing will happen if you directly call the `set wlan phrase`
command in the WiFly command mode; it swaps $ for space already, so this
is known, if somewhat unexpected, behavior. Dollar signs aren't valid
characters in an SSID, so it shouldn't be a problem there.