src/server/handler_door.c

   1 /*
   2  * OpenDispense 2
   3  * UCC (University [of WA] Computer Club) Electronic Accounting System
   4  *
   5  * handler_door.c - Door Relay code
   6  *
   7  * This file is licenced under the 3-clause BSD Licence. See the file
   8  * COPYING for full details.
   9  */
  10 #define DEBUG   1
  11
  12 #include "common.h"
  13 #include <stdio.h>
  14 #include <string.h>
  15 #include <unistd.h>
  16 #include <sys/stat.h>
  17 #include <fcntl.h>
  18 #include <signal.h>
  19 #include <unistd.h>
  20 #include <pty.h>
  21 #include <pthread.h>
  22 #include <semaphore.h>
  23 #include <errno.h>
  24 #include <stdbool.h>
  25
  26 #define DOOR_UNLOCKED_DELAY     10      // Time in seconds before the door re-locks
  27
  28 // === IMPORTS ===
  29
  30 // === PROTOTYPES ===
  31 void*   Door_Lock(void* Unused);
  32  int    Door_InitHandler();
  33  int    Door_CanDispense(int User, int Item);
  34  int    Door_DoDispense(int User, int Item);
  35
  36 // === GLOBALS ===
  37 tHandler        gDoor_Handler = {
  38         "door",
  39         Door_InitHandler,
  40         Door_CanDispense,
  41         Door_DoDispense
  42 };
  43 char    *gsDoor_SerialPort;     // Set from config in main.c
  44 sem_t   gDoor_UnlockSemaphore;
  45 pthread_t       gDoor_LockThread;
  46 bool    gbDoor_LockThreadStarted;
  47
  48 // === CODE ===
  49 void* Door_Lock(void* Unused __attribute__((unused)))
  50 {
  51         while(1)
  52         {
  53                 sem_wait(&gDoor_UnlockSemaphore);
  54
  55                 int door_serial_handle = InitSerial(gsDoor_SerialPort, 9600);
  56                 if(door_serial_handle < 0)
  57                 {
  58                         fprintf(stderr, "Unable to open door serial '%s'\n", gsDoor_SerialPort);
  59                         perror("Opening door port");
  60                 }
  61
  62                 // Disable local echo
  63                 {
  64                         struct termios  info;
  65                         tcgetattr(door_serial_handle, &info);
  66                         info.c_cflag &= ~CLOCAL;
  67                         tcsetattr(door_serial_handle, TCSANOW, &info);
  68                 }
  69
  70                 if(write(door_serial_handle, "\xff\x01\x01", 3) != 3)   // Relay ON
  71                 {
  72                         fprintf(stderr, "Failed to write Relay ON (unlock) command, errstr: %s", strerror(errno));
  73                 }
  74
  75                 sleep(DOOR_UNLOCKED_DELAY);
  76
  77                 if(write(door_serial_handle, "\xff\x01\x00", 3) != 3)   // Relay OFF
  78                 {
  79                         fprintf(stderr, "Failed to write Relay OFF (lock) command, errstr: %s", strerror(errno));
  80                 }
  81
  82                 close(door_serial_handle);
  83         }
  84 }
  85
  86 int Door_InitHandler(void)
  87 {
  88         // Thread started later
  89
  90         return 0;
  91 }
  92
  93 /**
  94  */
  95 int Door_CanDispense(int User, int Item)
  96 {
  97         #if DEBUG
  98         printf("Door_CanDispense: (User=%i,Item=%i)\n", User, Item);
  99         #endif
 100         // Sanity please
 101         if( Item != 0 ) return -1;
 102
 103         if( !(Bank_GetFlags(User) & USER_FLAG_DOORGROUP) )
 104         {
 105                 #if DEBUG
 106                 printf("Door_CanDispense: User %i not in door\n", User);
 107                 #endif
 108                 return 1;
 109         }
 110
 111         #if DEBUG
 112         printf("Door_CanDispense: User %i can open the door\n", User);
 113         #endif
 114
 115         return 0;
 116 }
 117
 118 /**
 119  * \brief Actually do a dispense from the coke machine
 120  */
 121 int Door_DoDispense(int User, int Item)
 122 {
 123         #if DEBUG
 124         printf("Door_DoDispense: (User=%i,Item=%i)\n", User, Item);
 125         #endif
 126
 127         // Sanity please
 128         if( Item != 0 ) return -1;
 129
 130         // Check if user is in door
 131         if( !(Bank_GetFlags(User) & USER_FLAG_DOORGROUP) )
 132         {
 133                 #if DEBUG
 134                 printf("Door_CanDispense: User %i not in door\n", User);
 135                 #endif
 136                 return 1;
 137         }
 138
 139         // Door thread spun up here because program is forked after thread created
 140         if( !gbDoor_LockThreadStarted )
 141         {
 142                 // Initialize semaphore, triggers door lock release if semaphore is greater than 0
 143                 sem_init(&gDoor_UnlockSemaphore, 0, 0);
 144
 145                 pthread_create(&gDoor_LockThread, NULL, &Door_Lock, NULL);
 146         }
 147
 148         if(sem_post(&gDoor_UnlockSemaphore))
 149         {
 150                 perror("Failed to post \"Unlock Door\" semaphore, sem_post returned");
 151                 return -1;
 152         }
 153
 154         #if DEBUG
 155         printf("Door_DoDispense: User %i opened door\n", User);
 156         #endif
 157
 158         return 0;
 159 }