Merge commit '60b30c036397cb5627fa374bb930794b225daa29' as 'lib/lufa'

[qmk_firmware.git] / lib / lufa / Projects / Webserver / Lib / DHCPCommon.c

diff --git a/lib/lufa/Projects/Webserver/Lib/DHCPCommon.c b/lib/lufa/Projects/Webserver/Lib/DHCPCommon.c
new file mode 100644 (file)
index 0000000..6d80f65
--- /dev/null
+++ b/lib/lufa/Projects/Webserver/Lib/DHCPCommon.c
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+/*
+             LUFA Library
+     Copyright (C) Dean Camera, 2017.
+
+  dean [at] fourwalledcubicle [dot] com
+           www.lufa-lib.org
+*/
+
+/*
+  Copyright 2017  Dean Camera (dean [at] fourwalledcubicle [dot] com)
+
+  Permission to use, copy, modify, distribute, and sell this
+  software and its documentation for any purpose is hereby granted
+  without fee, provided that the above copyright notice appear in
+  all copies and that both that the copyright notice and this
+  permission notice and warranty disclaimer appear in supporting
+  documentation, and that the name of the author not be used in
+  advertising or publicity pertaining to distribution of the
+  software without specific, written prior permission.
+
+  The author disclaims all warranties with regard to this
+  software, including all implied warranties of merchantability
+  and fitness.  In no event shall the author be liable for any
+  special, indirect or consequential damages or any damages
+  whatsoever resulting from loss of use, data or profits, whether
+  in an action of contract, negligence or other tortious action,
+  arising out of or in connection with the use or performance of
+  this software.
+*/
+
+/** \file
+ *
+ *  Common DHCP routines to manage DHCP packet data.
+ */
+
+#include "DHCPCommon.h"
+
+#if defined(ENABLE_DHCP_CLIENT) || defined(ENABLE_DHCP_SERVER) || defined(__DOXYGEN__)
+
+/** Sets the given DHCP option in the DHCP packet's option list. This automatically moves the
+ *  end of options terminator past the new option in the options list.
+ *
+ *  \param[in,out] DHCPOptionList  Pointer to the start of the DHCP packet's options list
+ *  \param[in]     Option          DHCP option to add to the list
+ *  \param[in]     DataLen         Size in bytes of the option data to add
+ *  \param[in]     OptionData      Buffer where the option's data is to be sourced from
+ *
+ *  \return Number of bytes added to the DHCP packet
+ */
+uint8_t DHCPCommon_SetOption(uint8_t* DHCPOptionList,
+                             const uint8_t Option,
+                             const uint8_t DataLen,
+                             void* const OptionData)
+{
+       /* Skip through the DHCP options list until the terminator option is found */
+       while (*DHCPOptionList != DHCP_OPTION_END)
+         DHCPOptionList += (DHCPOptionList[1] + 2);
+
+       /* Overwrite the existing terminator with the new option, add a new terminator at the end of the list */
+       DHCPOptionList[0] = Option;
+       DHCPOptionList[1] = DataLen;
+       memcpy(&DHCPOptionList[2], OptionData, DataLen);
+       DHCPOptionList[2 + DataLen] = DHCP_OPTION_END;
+
+       /* Calculate the total number of bytes added to the outgoing packet */
+       return (2 + DataLen);
+}
+
+/** Retrieves the given option's data (if present) from the DHCP packet's options list.
+ *
+ *  \param[in,out] DHCPOptionList  Pointer to the start of the DHCP packet's options list
+ *  \param[in]     Option          DHCP option to retrieve to the list
+ *  \param[out]    Destination     Buffer where the option's data is to be written to if found
+ *
+ *  \return Boolean \c true if the option was found in the DHCP packet's options list, \c false otherwise
+ */
+bool DHCPCommon_GetOption(const uint8_t* DHCPOptionList,
+                          const uint8_t Option,
+                          void* const Destination)
+{
+       /* Look through the incoming DHCP packet's options list for the requested option */
+       while (*DHCPOptionList != DHCP_OPTION_END)
+       {
+               /* Check if the current DHCP option in the packet is the one requested */
+               if (DHCPOptionList[0] == Option)
+               {
+                       /* Copy request option's data to the destination buffer */
+                       memcpy(Destination, &DHCPOptionList[2], DHCPOptionList[1]);
+
+                       /* Indicate that the requested option data was successfully retrieved */
+                       return true;
+               }
+
+               /* Skip to next DHCP option in the options list */
+               DHCPOptionList += (DHCPOptionList[1] + 2);
+       }
+
+       /* Requested option not found in the incoming packet's DHCP options list */
+       return false;
+}
+
+#endif
+