*
* This file is licenced under the 3-clause BSD Licence. See the file
* COPYING for full details.
+ *
+ * NOTES:
+ * - Remember, the coke machine echoes your text back to you!
*/
#include "common.h"
#include <stdio.h>
#include <fcntl.h>
#include <regex.h>
+#define READ_TIMEOUT 2 // 2 seconds for ReadChar
+#define TRACE_COKE 1
+
// === IMPORTS ===
// === PROTOTYPES ===
int Coke_InitHandler();
int Coke_CanDispense(int User, int Item);
int Coke_DoDispense(int User, int Item);
+ int WaitForColon();
+ int ReadLine(int len, char *output);
// === GLOBALS ===
tHandler gCoke_Handler = {
int Coke_InitHandler()
{
printf("connecting to coke machine...\n");
- giCoke_SerialFD = open(gsCoke_SerialPort, O_RDWR);
+
+ giCoke_SerialFD = InitSerial(gsCoke_SerialPort, 9600);
if( giCoke_SerialFD == -1 ) {
fprintf(stderr, "ERROR: Unable to open coke serial port ('%s')\n", gsCoke_SerialPort);
}
- CompileRegex(&gCoke_StatusRegex, "^slot\\s+(\\d)\\s+([^:]+):([a-zA-Z]+)\\s*", REG_EXTENDED);
+
+ CompileRegex(&gCoke_StatusRegex, "^slot\\s+([0-9]+)\\s+([^:]+):([a-zA-Z]+)\\s*", REG_EXTENDED);
return 0;
}
-int Coke_CanDispense(int User, int Item)
+int Coke_CanDispense(int UNUSED(User), int Item)
{
- char tmp[32], *status;
+ char tmp[40], *status;
regmatch_t matches[4];
int ret;
// Sanity please
if( Item < 0 || Item > 6 ) return -1; // -EYOURBAD
+ // Can't dispense if the machine is not connected
+ if( giCoke_SerialFD == -1 )
+ return -2;
+
+ #if TRACE_COKE
+ printf("Coke_CanDispense: Flushing\n");
+ #endif
+
+
+ // Wait for a prompt
+ ret = 0;
+ while( WaitForColon() && ret < 3 )
+ {
+ // Flush the input buffer
+ char tmpbuf[512];
+ read(giCoke_SerialFD, tmpbuf, sizeof(tmpbuf));
+ #if TRACE_COKE
+ printf("Coke_CanDispense: sending 'd7'\n");
+ #endif
+ write(giCoke_SerialFD, "d7\r\n", 4);
+ ret ++;
+ }
+
+ if( !(ret < 3) ) {
+ fprintf(stderr, "Coke machine timed out\n");
+ return -2; // -EMYBAD
+ }
+
+ // TODO: Handle "not ok" response to D7
+
+ #if TRACE_COKE
+ printf("Coke_CanDispense: sending 's%i'\n", Item);
+ #endif
+
// Ask the coke machine
- sprintf(tmp, "s%i\n", Item);
- write(giCoke_SerialFD, tmp, 2);
+ sprintf(tmp, "s%i\r\n", Item);
+ write(giCoke_SerialFD, tmp, 4);
+
+ #if TRACE_COKE
+ printf("Coke_CanDispense: reading response\n");
+ #endif
+ // Read from the machine (ignoring empty lines)
+ while( (ret = ReadLine(sizeof(tmp)-1, tmp)) == 0 );
+ printf("ret = %i, tmp = '%s'\n", ret, tmp);
+ // Read back-echoed lines
+ while( tmp[0] == ':' || tmp[1] != 'l' )
+ {
+ ret = ReadLine(sizeof(tmp)-1, tmp);
+ printf("ret = %i, tmp = '%s'\n", ret, tmp);
+ }
- // Read the response
- tmp[0] = '\0';
- ret = read(giCoke_SerialFD, tmp, sizeof(tmp)-1);
- //printf("ret = %i\n", ret);
+ // Catch an error
if( ret <= 0 ) {
fprintf(stderr, "Coke machine is not being chatty (read = %i)\n", ret);
+ if( ret == -1 ) {
+ perror("Coke Machine");
+ }
return -1;
}
+
+ #if TRACE_COKE
+ printf("Coke_CanDispense: wait for the prompt again\n");
+ #endif
+
+ // Eat rest of response
+ WaitForColon();
+
+ // Parse status response
ret = RunRegex(&gCoke_StatusRegex, tmp, sizeof(matches)/sizeof(matches[0]), matches, "Bad Response");
if( ret ) {
return -1;
}
+ // Get slot status
tmp[ matches[3].rm_eo ] = '\0';
status = &tmp[ matches[3].rm_so ];
printf("Machine responded slot status '%s'\n", status);
+
+ #if TRACE_COKE
+ printf("Coke_CanDispense: done");
+ #endif
if( strcmp(status, "full") == 0 )
- return 1;
+ return 0;
- return 0;
+ return 1;
}
/**
* \brief Actually do a dispense from the coke machine
*/
-int Coke_DoDispense(int User, int Item)
+int Coke_DoDispense(int UNUSED(User), int Item)
{
- char tmp[32], *status;
- regmatch_t matches[4];
+ char tmp[32];
+ int ret;
// Sanity please
if( Item < 0 || Item > 6 ) return -1;
+ // Can't dispense if the machine is not connected
+ if( giCoke_SerialFD == -1 )
+ return -2;
+
+ #if TRACE_COKE
+ printf("Coke_DoDispense: flushing input\n");
+ #endif
+
+ // Wait for prompt
+ ret = 0;
+ while( WaitForColon() && ret < 3 )
+ {
+ // Flush the input buffer
+ char tmpbuf[512];
+ read(giCoke_SerialFD, tmpbuf, sizeof(tmpbuf));
+ #if TRACE_COKE
+ printf("Coke_DoDispense: sending 'd7'\n");
+ #endif
+ write(Item, "d7\r\n", 4);
+ }
+
+ #if TRACE_COKE
+ printf("Coke_DoDispense: sending 'd%i'\n", Item);
+ #endif
// Dispense
- sprintf(tmp, "d%i\n", Item);
- write(giCoke_SerialFD, tmp, 2);
+ sprintf(tmp, "d%i\r\n", Item);
+ write(giCoke_SerialFD, tmp, 4);
+
+ // Read empty lines and echo-backs
+ do {
+ ret = ReadLine(sizeof(tmp)-1, tmp);
+ if( ret == -1 ) return -1;
+ #if TRACE_COKE
+ printf("Coke_DoDispense: read %i '%s'\n", ret, tmp);
+ #endif
+ } while( ret == 0 || tmp[0] == ':' || tmp[0] == 'd' );
- // Get status
- read(giCoke_SerialFD, tmp, sizeof(tmp)-1);
- regexec(&gCoke_StatusRegex, tmp, sizeof(matches)/sizeof(matches[0]), matches, 0);
+ WaitForColon(); // Eat up rest of response
- tmp[ matches[3].rm_eo ] = '\0';
- status = &tmp[ matches[3].rm_so ];
+ #if TRACE_COKE
+ printf("Coke_DoDispense: done\n");
+ #endif
- printf("Machine responded slot status '%s'\n", status);
+ // TODO: Regex
+ if( strcmp(tmp, "ok") == 0 ) {
+ // We think dispense worked
+ // - The machine returns 'ok' if an empty slot is dispensed, even if
+ // it doesn't actually try to dispense (no sound)
+ return 0;
+ }
+
+ printf("Machine returned unknown value '%s'\n", tmp);
+
+ return -1;
+}
+
+char ReadChar()
+{
+ fd_set readfs;
+ char ch = 0;
+ int ret;
+ struct timeval timeout;
+
+ timeout.tv_sec = READ_TIMEOUT;
+ timeout.tv_usec = 0;
+
+ FD_ZERO(&readfs);
+ FD_SET(giCoke_SerialFD, &readfs);
+
+ ret = select(giCoke_SerialFD+1, &readfs, NULL, NULL, &timeout);
+ if( ret == 0 ) return 0; // Timeout
+ if( ret != 1 ) {
+ printf("readchar return %i\n", ret);
+ return 0;
+ }
+
+ ret = read(giCoke_SerialFD, &ch, 1);
+ if( ret != 1 ) {
+ printf("ret = %i\n", ret);
+ return 0;
+ }
+
+ return ch;
+}
+int WaitForColon()
+{
+ fd_set readfs;
+ char ch = 0;
+
+ FD_SET(giCoke_SerialFD, &readfs);
+
+ while( (ch = ReadChar()) != ':' && ch != 0);
+
+ if( ch == 0 ) return -1; // Timeout
+
return 0;
}
+int ReadLine(int len, char *output)
+{
+ char ch;
+ int i = 0;
+
+ for(;;)
+ {
+ ch = ReadChar();
+
+ if( i < len )
+ output[i++] = ch;
+
+ if( ch == '\0' ) {
+ break;
+ }
+ if( ch == '\n' || ch == '\r' ) {
+ if( i < len )
+ output[--i] = '\0';
+ break;
+ }
+ }
+
+ //printf("ReadLine: output=%s\n", output);
+
+ if( !ch ) return -1;
+ return i;
+}
+