src/options.c

   1 #include "options.h"
   2 #include <string.h>
   3 #include <stdlib.h>
   4 #include <time.h>
   5 #include <unistd.h>
   6 #include "log.h"
   7 #include <errno.h>
   8 #include <sys/types.h>
   9 #include <sys/stat.h>
  10 #include <fcntl.h>
  11 #include "daemon.h"
  12 #include <signal.h>
  13
  14
  15 void remove_command()
  16 {
  17         remove(COMMAND_FILE);
  18
  19 }
  20
  21 void remove_daemon()
  22 {
  23         remove(DAEMON_PID_FILE);
  24         remove(DAEMON_FIFO);
  25         remove(DAEMON_BARRIER_FIFO);
  26 }
  27
  28 void close_err()
  29 {
  30         fclose(stderr);
  31 }
  32
  33 void close_out()
  34 {
  35         fclose(stdout);
  36 }
  37
  38 void Initialise(int argc, char ** argv, Options * o)
  39 {
  40         srand(time(NULL));
  41         o->program = argv[0];
  42         o->master_addr = NULL;
  43         o->shell = "bash"; // choosing other shells seems to not work... for some reason
  44         o->logfile = NULL;
  45         o->outfile = NULL;
  46         o->verbosity = 2;
  47         o->port = 4000 + rand() % 1000;
  48         o->slavefile = "slaves.swarm";
  49         o->dummy_shell = false;
  50         o->append = NULL;
  51         o->prepend = NULL;
  52         o->end = "\a\a\a";
  53         o->nCPU = sysconf( _SC_NPROCESSORS_ONLN );
  54         o->daemon = false;
  55         o->encrypt = true;
  56         o->interactive = true;
  57
  58
  59         o->master_pid = getpid();
  60
  61         ParseArguments(argc, argv, o);
  62
  63         o->endlen = (o->end != NULL) ? strlen(o->end) : 0;
  64
  65         if (!o->daemon)
  66         {
  67                 FILE * f = fopen(DAEMON_PID_FILE, "r");
  68                 if (f != NULL)
  69                 {
  70                         int daemon_pid;
  71                         fscanf(f, "%d", &daemon_pid);
  72                         fclose(f);
  73                         if (kill(daemon_pid, 0) != 0)
  74                         {
  75                                 error("Initialise", "There was a daemon [%d] running here, but it's gone for some reason.", daemon_pid);
  76                         }
  77                         o->daemon_wrapper = true;
  78
  79                 }
  80         }
  81         else
  82                 o->daemon_wrapper = false;
  83
  84         if (o->logfile != NULL)
  85         {
  86                 if (o->logfile[0] == '+')
  87                         freopen(o->logfile+1, "a", stderr);
  88                 else
  89                         freopen(o->logfile, "w", stderr);
  90
  91                 setbuf(stderr, NULL);
  92                 atexit(close_err);
  93         }
  94         if (o->outfile != NULL)
  95         {
  96                 if (o->outfile[0] == '+')
  97                         freopen(o->outfile+1, "a", stdout);
  98                 else
  99                         freopen(o->outfile, "w", stdout);
 100                 atexit(close_out);
 101         }
 102
 103         if (o->verbosity >= 3)
 104         {
 105                 char buffer[BUFSIZ]; getcwd(buffer, BUFSIZ);
 106                 char * type = (o->daemon) ? "daemon" : (o->daemon_wrapper) ? "wrapper" : (o->master_addr != NULL) ? "slave" : "interactive";
 107                 log_print(3, "Initialise", "Directory %s; type of instance: %s", buffer, type);
 108         }
 109         if (o->daemon_wrapper && o->interactive)
 110         {
 111                 log_print(1, "Initialise", "There is a daemonised swarm [%d] running in this directory.");
 112                 log_print(1, "Initialise", "You can only pass commands to the daemon by invoking %s -c [command]", options.program);
 113                 log_print(1, "Initialise", "Running `swarm -c \"#EXIT#\"' will quit the daemon, unless it is waiting on a BARRIER");
 114                 error("Initialise", "Can't run an interactive wrapper to a daemon");
 115         }
 116
 117 }
 118
 119 void ParseArguments(int argc, char ** argv, Options * o)
 120 {
 121
 122         for (int i = 1; i < argc; ++i)
 123         {
 124                 if (argv[i][0] == '-' && argv[i][2] == '\0')
 125                 {
 126
 127
 128
 129
 130
 131                         if (argv[i][1] == 'p')
 132                         {
 133                                 if (i >= argc-1)
 134                                         error("ParseArguments", "No argument following %s switch", argv[i]);
 135                                 o->port = atoi(argv[++i]);
 136                         }
 137                         else if (argv[i][1] == 'n')
 138                         {
 139                                 if (i >= argc-1)
 140                                         error("ParseArguments", "No argument following %s switch", argv[i]);
 141                                 o->nCPU = atoi(argv[++i]);
 142                         }
 143                         else if (argv[i][1] == 'm')
 144                         {
 145                                 if (i >= argc-1)
 146                                         error("ParseArguments", "No argument following %s switch", argv[i]);
 147                                 o->master_addr = argv[++i];
 148                         }
 149                         else if (argv[i][1] == 'c')
 150                         {
 151
 152                                 if (i >= argc-1)
 153                                         error("ParseArguments", "No argument following %s switch", argv[i]);
 154
 155                                 if (!o->interactive)
 156                                         error("ParseArguments", "Can't use %s switch in combination with a script", argv[i]);
 157
 158                                 // insert terrible hack here
 159                                 o->interactive = false;
 160                                 FILE * f = fopen(COMMAND_FILE, "a");
 161                                 fprintf(f, "%s\n", argv[++i]);
 162                                 fclose(f);
 163                                 dup2(open(COMMAND_FILE, O_RDONLY), fileno(stdin));
 164                                 atexit(remove_command);
 165                         }
 166                         else if (argv[i][1] == 's')
 167                         {
 168                                 if (i >= argc-1)
 169                                         error("ParseArguments", "No argument following %s switch", argv[i]);
 170
 171                                 o->shell = argv[++i]; // obviously this breaks things
 172                         }
 173                         else if (argv[i][1] == 'l')
 174                         {
 175                                 if (i >= argc-1)
 176                                         error("ParseArguments", "No argument following %s switch", argv[i]);
 177
 178                                 char * l = argv[++i];
 179                                 while (*l != '\0') if (*(l++) == ':') break;
 180                                 if (*l != '\0')
 181                                 {
 182                                         o->verbosity = atoi(l);
 183                                         *(l-1) = 0;
 184                                 }
 185                                 if (argv[i][0] != '\0')
 186                                         o->logfile = argv[i];
 187
 188                         }
 189                         else if (argv[i][1] == 'o')
 190                         {
 191                                 if (i >= argc-1)
 192                                         error("ParseArguments", "No argument following %s switch", argv[i]);
 193
 194                                 o->outfile = argv[++i];
 195                         }
 196                         else if (argv[i][1] == 'e')
 197                                 o->encrypt = true;
 198                         else if (argv[i][1] == 'u')
 199                                 o->encrypt = false;
 200                         else
 201                         {
 202                                 fprintf(stderr, "%s : Unrecognised switch \"%s\"\n", argv[0], argv[i]);
 203                                 exit(EXIT_FAILURE);
 204                         }
 205                 }
 206                 else if (strcmp(argv[i], "--daemon") == 0)
 207                 {
 208                         FILE * f = fopen(DAEMON_PID_FILE, "r");
 209                         if (f != NULL)
 210                         {
 211                                 int daemon_pid; fscanf(f, "%d\n", &daemon_pid);
 212                                 fclose(f);
 213
 214                                 if (kill(daemon_pid, 0) != 0)
 215                                 {
 216                                         if (errno == ESRCH)
 217                                         {
 218                                                 log_print(0, "ParseArguments", "It looks like a daemon [%d] failed to exit cleanly. Starting a new daemon.", daemon_pid);
 219                                                 remove_daemon();
 220                                         }
 221                                         else
 222                                         {
 223                                                 error("ParseArguments", "Couldn't determine whether a daemon [%d] was already running : %s", daemon_pid, strerror(errno));
 224                                         }
 225                                 }
 226                                 else
 227                                         error("ParseArguments", "A daemon is already running!");
 228                         }
 229
 230                         int pid = fork();
 231                         if (pid != 0)
 232                         {
 233                                 //setbuf(stdout, NULL);
 234                                 //fprintf(stdout, "%d\n", pid);
 235                                 exit(EXIT_SUCCESS); // fork off into daemon
 236                         }
 237                         atexit(remove_daemon);
 238
 239                         f = fopen(DAEMON_PID_FILE, "w");
 240                         if (f == NULL)
 241                                 error("ParseArguments", "Couldn't open %s : %s", DAEMON_PID_FILE, strerror(errno));
 242                         fprintf(f, "%d", getpid()); fclose(f);
 243
 244                         fprintf(stdout, "%d\n", getpid());
 245                         freopen("/dev/null", "w", stdout);
 246                         freopen("/dev/null", "w", stderr);
 247
 248                         mkfifo(DAEMON_FIFO, 0600);
 249                         mkfifo(DAEMON_BARRIER_FIFO, 0600);
 250                         freopen(DAEMON_FIFO, "r", stdin);
 251
 252                         o->daemon = true;
 253
 254
 255                 }
 256                 else if (o->interactive)
 257                 {
 258                         o->interactive = false;
 259                         dup2(open(argv[i], O_RDONLY), fileno(stdin)); // replace stdin
 260                 }
 261                 else
 262                 {
 263                         fprintf(stderr, "%s : Usage %s [options] [script]\n", argv[0], argv[0]);
 264                         fprintf(stderr, "%s : (extra argv[%d] %s)\n", argv[0], i, argv[i]);
 265                         exit(EXIT_FAILURE);
 266                 }
 267         }
 268 }
 269
 270
 271 char * strdup(const char * str)
 272 {
 273         int n = strlen(str) + 1;
 274         char * dup = (char*)(calloc(n, sizeof(char)));
 275         if (dup != NULL)
 276         {
 277                 strcpy(dup, str);
 278         }
 279         return dup;
 280 }
 281
 282