lib/gtkNode/src/gtkNode_cnode.c

   1 #include <string.h>
   2 #include "gtkNode.h"
   3
   4 #define CREATION 1
   5 #define REMNODE argv[1]
   6 #define REMHOST argv[2]
   7 #define REMREG argv[3]
   8 #define COOKIE argv[4]
   9 #define NODE_NAME argv[5]
  10 #define ERL_DIST_VSN atoi(argv[6])
  11
  12 static int fd;                  /* fd to remote Erlang node */
  13 static gchar* rem_regname;    /* process name on remote Erlang node */
  14
  15 int gn_start_cnode(char **argv) {
  16   extern ei_cnode ec;
  17   char rem_node_name[MAXATOMLEN] = "";  /* other node name */
  18   ei_x_buff xbuf;
  19   erlang_pid *self = ei_self(&ec);
  20
  21   strcat(rem_node_name,REMNODE);
  22   strcat(rem_node_name,"@");
  23   strcat(rem_node_name,REMHOST);
  24   rem_regname = g_strdup(REMREG);
  25   g_print("I am %s, you are %s\n", NODE_NAME, rem_node_name);
  26
  27   ei_set_compat_rel(ERL_DIST_VSN); /* erlnode version of dist. protocol */
  28
  29   if ( ei_connect_init(&ec, NODE_NAME, COOKIE, CREATION) < 0 )
  30     g_critical("ei_connect_init");
  31
  32   if ( (fd = ei_connect(&ec, rem_node_name)) < 0 )
  33     g_critical("ei_connect failed.\nwrong cookie? erl-dist version mismatch?");
  34
  35   self->num = fd;               /* bug?? in ei_reg_send_tmo */
  36
  37   ei_x_new_with_version(&xbuf);
  38   gn_wrap_ans("handshake", &xbuf);
  39   ei_x_encode_empty_list(&xbuf);
  40   gn_send(&xbuf);
  41   ei_x_free(&xbuf);
  42
  43   return fd;
  44 }
  45
  46 void gn_send(ei_x_buff *xbuf) {
  47   extern ei_cnode ec;
  48
  49   if ( ei_reg_send(&ec, fd, rem_regname, xbuf->buff, xbuf->index) )
  50     g_critical("bad send");
  51 }
  52
  53 static gboolean get_fpointer(char *cmd, ei_x_buff *xbuf, gpointer* poi) {
  54   extern GModule* gmod;
  55
  56   if ( ! g_module_supported() ) g_critical("gtkNode requires working gmodule");
  57
  58   if ( ! gmod ) gmod = g_module_open(NULL,0); /* "gtkNode_gtk.so" */
  59
  60   if ( g_module_symbol(gmod, cmd, poi) ) return TRUE;
  61
  62   g_warning("could not find '%s'.", cmd);
  63   gn_enc_2_error(xbuf, "no_such_function");
  64   ei_x_encode_atom(xbuf, cmd);
  65   return FALSE;
  66 }
  67
  68 static gboolean make_reply(ei_x_buff *xbuf, char *buff, int *index) {
  69   int k;
  70   gint arity;
  71   gchar cmd[MAXATOMLEN+1];
  72   gboolean (*funcp)(int, ei_x_buff *, char *, int *);
  73
  74   if ( ! ((arity = gn_get_tuple(xbuf, buff, index)) > -1) ||
  75        ! gn_check_arity(xbuf,2,arity)  ||
  76        ! gn_get_arg_gchar_fix(xbuf, buff, index, cmd) ||
  77        ! ((arity = gn_get_list(xbuf, buff, index)) > -1) )
  78     return FALSE;
  79
  80   if ( get_fpointer(cmd, xbuf, (gpointer *)&funcp) &&
  81        (*funcp)(arity, xbuf, buff, index) ) {
  82     g_assert( ei_decode_list_header(buff,index,&k) == 0 );
  83     g_assert( k == 0 );
  84     return TRUE;
  85   }
  86
  87   return FALSE;
  88 }
  89
  90 static void make_reply_list(ei_x_buff *xbuf, char *buff, int *index) {
  91
  92   gint arity, i;
  93
  94   if ( ! ((arity = gn_get_list(xbuf, buff, index)) > -1) )
  95     return;
  96
  97   gn_wrap_ans("reply",xbuf);
  98   for (i = 0; i < arity; i++) {
  99     ei_x_encode_list_header(xbuf, 1);
 100     if ( ! make_reply(xbuf, buff, index) )
 101       break;
 102   }
 103   ei_x_encode_empty_list(xbuf);
 104 }
 105
 106
 107 static void reply(erlang_msg *msg, ei_x_buff *recv_x_buf) {
 108   int i = 0;
 109   int version;
 110   ei_x_buff xbuf;
 111
 112   ei_decode_version(recv_x_buf->buff, &i, &version);
 113   ei_x_new_with_version(&xbuf);
 114   make_reply_list(&xbuf, recv_x_buf->buff, &i);
 115   gn_send(&xbuf);
 116   ei_x_free(&xbuf);
 117 }
 118
 119 /* called from gtk main loop when there's data on the cnode socket */
 120 gboolean gn_handle_read(GIOChannel *source,GIOCondition cond,gpointer data){
 121   erlang_msg msg;
 122   ei_x_buff xbuf;
 123
 124   /*   fd = g_io_channel_unix_get_fd(source); */
 125   ei_x_new_with_version(&xbuf);
 126   switch ( ei_xreceive_msg(fd, &msg, &xbuf) ){
 127   case ERL_TICK:
 128     break;                      /* ignore */
 129   case ERL_MSG:
 130     switch (msg.msgtype) {
 131     case ERL_SEND:
 132     case ERL_REG_SEND:
 133       reply(&msg, &xbuf);
 134       break;
 135     case ERL_LINK:
 136     case ERL_UNLINK:
 137     case ERL_GROUP_LEADER:
 138       break;                    /* ignore */
 139     case ERL_EXIT:
 140     case ERL_EXIT2:
 141     case ERL_NODE_LINK:
 142       gtk_main_quit();          /* crash and burn */
 143       return FALSE;
 144     }
 145     break;
 146   case ERL_ERROR:
 147     gtk_main_quit();            /* crash and burn */
 148     return FALSE;
 149   }
 150   ei_x_free(&xbuf);
 151   return TRUE;
 152 }