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 char name[BUFSIZ];
  39
  40 void Initialise(int argc, char ** argv, Options * o)
  41 {
  42         srand(time(NULL));
  43         o->program = argv[0];
  44         o->master_addr = NULL;
  45         o->shell = "bash"; // choosing other shells seems to not work... for some reason
  46         o->logfile = NULL;
  47         o->outfile = NULL;
  48         o->verbosity = 2;
  49         o->port = 0;
  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         gethostname(name, sizeof(name));
  59         o->name = strdup(name);
  60
  61         o->master_pid = getpid();
  62
  63         ParseArguments(argc, argv, o);
  64
  65         o->endlen = (o->end != NULL) ? strlen(o->end) : 0;
  66
  67         if (!o->daemon)
  68         {
  69                 FILE * f = fopen(DAEMON_PID_FILE, "r");
  70                 if (f != NULL)
  71                 {
  72                         int daemon_pid;
  73                         fscanf(f, "%d", &daemon_pid);
  74                         fclose(f);
  75                         if (kill(daemon_pid, 0) != 0)
  76                         {
  77                                 error("Initialise", "There was a daemon [%d] running here, but it's gone for some reason.", daemon_pid);
  78                         }
  79                         o->daemon_wrapper = true;
  80
  81                 }
  82         }
  83         else
  84                 o->daemon_wrapper = false;
  85
  86         if (o->logfile != NULL)
  87         {
  88                 if (o->logfile[0] == '+')
  89                         freopen(o->logfile+1, "a", stderr);
  90                 else
  91                         freopen(o->logfile, "w", stderr);
  92
  93                 setbuf(stderr, NULL);
  94                 atexit(close_err);
  95         }
  96         if (o->outfile != NULL)
  97         {
  98                 if (o->outfile[0] == '+')
  99                         freopen(o->outfile+1, "a", stdout);
 100                 else
 101                         freopen(o->outfile, "w", stdout);
 102                 atexit(close_out);
 103         }
 104
 105         if (o->verbosity >= 3)
 106         {
 107                 char buffer[BUFSIZ]; getcwd(buffer, BUFSIZ);
 108                 char * type = (o->daemon) ? "daemon" : (o->daemon_wrapper) ? "wrapper" : (o->master_addr != NULL) ? "slave" : "interactive";
 109                 log_print(3, "Initialise", "Directory %s; type of instance: %s", buffer, type);
 110         }
 111         if (o->daemon_wrapper && o->interactive)
 112         {
 113                 log_print(1, "Initialise", "There is a daemonised swarm [%d] running in this directory.");
 114                 log_print(1, "Initialise", "You can only pass commands to the daemon by invoking %s -c [command]", options.program);
 115                 log_print(1, "Initialise", "Running `swarm -c \"#EXIT#\"' will quit the daemon, unless it is waiting on a BARRIER");
 116                 error("Initialise", "Can't run an interactive wrapper to a daemon");
 117         }
 118
 119 }
 120
 121 void ParseArguments(int argc, char ** argv, Options * o)
 122 {
 123
 124         for (int i = 1; i < argc; ++i)
 125         {
 126                 if (argv[i][0] == '-' && argv[i][2] == '\0')
 127                 {
 128
 129
 130
 131
 132
 133                         if (argv[i][1] == 'p')
 134                         {
 135                                 if (i >= argc-1)
 136                                         error("ParseArguments", "No argument following %s switch", argv[i]);
 137                                 o->port = atoi(argv[++i]);
 138                         }
 139                         else if (argv[i][1] == 'n')
 140                         {
 141                                 if (i >= argc-1)
 142                                         error("ParseArguments", "No argument following %s switch", argv[i]);
 143                                 o->nCPU = atoi(argv[++i]);
 144                         }
 145                         else if (argv[i][1] == 'r')
 146                         {
 147                                 if (i >= argc-1)
 148                                         error("ParseArguments", "No argument following %s switch", argv[i]);
 149                                 o->master_addr = argv[++i];
 150                                 char * p = strstr(o->master_addr, ":");
 151                                 if (p != NULL)
 152                                 {
 153                                         *(p-1) = '\0';
 154                                         o->port = atoi(p);
 155                                 }
 156                         }
 157                         else if (argv[i][1] == 'c')
 158                         {
 159
 160                                 if (i >= argc-1)
 161                                         error("ParseArguments", "No argument following %s switch", argv[i]);
 162
 163                                 if (!o->interactive)
 164                                         error("ParseArguments", "Can't use %s switch in combination with a script", argv[i]);
 165
 166                                 // insert terrible hack here
 167                                 o->interactive = false;
 168                                 FILE * f = fopen(COMMAND_FILE, "a");
 169                                 fprintf(f, "%s\n", argv[++i]);
 170                                 fclose(f);
 171                                 dup2(open(COMMAND_FILE, O_RDONLY), fileno(stdin));
 172                                 atexit(remove_command);
 173                         }
 174                         else if (argv[i][1] == 's')
 175                         {
 176                                 if (i >= argc-1)
 177                                         error("ParseArguments", "No argument following %s switch", argv[i]);
 178
 179                                 o->shell = argv[++i]; // obviously this breaks things
 180                         }
 181                         else if (argv[i][1] == 'l')
 182                         {
 183                                 if (i >= argc-1)
 184                                         error("ParseArguments", "No argument following %s switch", argv[i]);
 185
 186                                 char * l = argv[++i];
 187                                 while (*l != '\0') if (*(l++) == ':') break;
 188                                 if (*l != '\0')
 189                                 {
 190                                         o->verbosity = atoi(l);
 191                                         *(l-1) = 0;
 192                                 }
 193                                 if (argv[i][0] != '\0')
 194                                         o->logfile = argv[i];
 195
 196                         }
 197                         else if (argv[i][1] == 'o')
 198                         {
 199                                 if (i >= argc-1)
 200                                         error("ParseArguments", "No argument following %s switch", argv[i]);
 201
 202                                 o->outfile = argv[++i];
 203                         }
 204                         else if (argv[i][1] == 'e')
 205                                 o->encrypt = true;
 206                         else if (argv[i][1] == 'u')
 207                                 o->encrypt = false;
 208                         else
 209                         {
 210                                 fprintf(stderr, "%s : Unrecognised switch \"%s\"\n", argv[0], argv[i]);
 211                                 exit(EXIT_FAILURE);
 212                         }
 213                 }
 214                 else if (strcmp(argv[i], "--daemon") == 0)
 215                 {
 216                         FILE * f = fopen(DAEMON_PID_FILE, "r");
 217                         if (f != NULL)
 218                         {
 219                                 int daemon_pid; fscanf(f, "%d\n", &daemon_pid);
 220                                 fclose(f);
 221
 222                                 if (kill(daemon_pid, 0) != 0)
 223                                 {
 224                                         if (errno == ESRCH)
 225                                         {
 226                                                 log_print(0, "ParseArguments", "It looks like a daemon [%d] failed to exit cleanly. Starting a new daemon.", daemon_pid);
 227                                                 remove_daemon();
 228                                         }
 229                                         else
 230                                         {
 231                                                 error("ParseArguments", "Couldn't determine whether a daemon [%d] was already running : %s", daemon_pid, strerror(errno));
 232                                         }
 233                                 }
 234                                 else
 235                                         error("ParseArguments", "A daemon is already running!");
 236                         }
 237
 238                         int pid = fork();
 239                         if (pid != 0)
 240                         {
 241                                 //setbuf(stdout, NULL);
 242                                 //fprintf(stdout, "%d\n", pid);
 243                                 exit(EXIT_SUCCESS); // fork off into daemon
 244                         }
 245                         atexit(remove_daemon);
 246
 247                         f = fopen(DAEMON_PID_FILE, "w");
 248                         if (f == NULL)
 249                                 error("ParseArguments", "Couldn't open %s : %s", DAEMON_PID_FILE, strerror(errno));
 250                         fprintf(f, "%d", getpid()); fclose(f);
 251
 252                         fprintf(stdout, "%d\n", getpid());
 253                         freopen("/dev/null", "w", stdout);
 254                         freopen("/dev/null", "w", stderr);
 255
 256                         mkfifo(DAEMON_FIFO, 0600);
 257                         mkfifo(DAEMON_BARRIER_FIFO, 0600);
 258                         freopen(DAEMON_FIFO, "r", stdin);
 259
 260                         o->daemon = true;
 261
 262
 263                 }
 264                 else if (o->interactive)
 265                 {
 266                         o->interactive = false;
 267                         dup2(open(argv[i], O_RDONLY), fileno(stdin)); // replace stdin
 268                 }
 269                 else
 270                 {
 271                         fprintf(stderr, "%s : Usage %s [options] [script]\n", argv[0], argv[0]);
 272                         fprintf(stderr, "%s : (extra argv[%d] %s)\n", argv[0], i, argv[i]);
 273                         exit(EXIT_FAILURE);
 274                 }
 275         }
 276 }
 277
 278
 279 char * strdup(const char * str)
 280 {
 281         int n = strlen(str) + 1;
 282         char * dup = (char*)(calloc(n, sizeof(char)));
 283         if (dup != NULL)
 284         {
 285                 strcpy(dup, str);
 286         }
 287         return dup;
 288 }
 289
 290