STMClientResponse.h

00001 #ifndef _STM_CLIENT_RESPONSE_H_
00002 #define _STM_CLIENT_RESPONSE_H_
00003 
00004 #if _MSC_VER
00005 #define PACKED
00006 #else
00007 #define PACKED __attribute__ ((__packed__))
00008 #endif
00009 
00010 #include <mbed.h>
00011 #include <string> 
00012 
00013 typedef struct PACKED {
00014   uint16_t cmd;            // command to execute
00015   uint16_t argc;           // number of arguments
00016   uint32_t value;          // callback to invoke, NULL if none; or response value
00017   uint8_t  args[0];
00018 } STMClientPacket;
00019 
00020 class STMClientResponse {
00021   public:
00022     // Create a response from a packet, this is done internally in STMClient
00023     STMClientResponse(STMClientPacket* packet);
00024     STMClientResponse(void *packet);
00025 
00026     // Accessors to the response fields
00027     uint16_t argc() { return _cmd->argc; }
00028     uint16_t cmd() { return _cmd->cmd; }
00029     uint32_t value() { return _cmd->value; }
00030 
00031     // Return the length of the next argument
00032     uint16_t argLen() { return *(uint16_t*)_arg_ptr; }
00033     // Pop one argument from the response, returns the actual length. Returns -1 if there is
00034     // no arg left.
00035     int16_t popArg(void* data, uint16_t maxLen);
00036     // Pop one argument as a poiner from the response, returns the actual length.
00037     int16_t popArgPtr(void **data);
00038     // Pop one argument into a string buffer and append a null character. The buffer needs to
00039     // be large enough (argLen()+1)
00040     void popChar(char* buffer);
00041     // Pop one argument into a String buffer
00042     string popString();
00043     // Pop one argument into a String buffer
00044     void popString(string* data);
00045 
00046   private:
00047     uint16_t _arg_num;
00048     uint8_t* _arg_ptr;
00049     STMClientPacket* _cmd;
00050 };
00051 
00052 #endif // _STM_CLIENT_RESPONSE_H_