ustd/ustd.c

   1 #define _GNU_SOURCE
   2
   3 #include <sys/types.h>
   4 #include <sys/shm.h>
   5
   6 #include <stdlib.h>
   7 #include <stdio.h>
   8 #include <string.h>
   9
  10 #include "localerr.h"
  11 #include "ustcomm.h"
  12
  13 struct list_head buffers = LIST_HEAD_INIT(buffers);
  14
  15 struct buffer_info {
  16         char *name;
  17         pid_t pid;
  18
  19         int shmid;
  20         void *mem;
  21         int memlen;
  22
  23         int n_subbufs;
  24         int subbuf_size;
  25
  26         int file_fd; /* output file */
  27 };
  28
  29 int add_buffer(pid_t pid, char *bufname)
  30 {
  31         struct buffer_info *buf;
  32         char *send_msg;
  33         char *received_msg;
  34         int result;
  35
  36         buf = (struct buffer_info *) malloc(sizeof(struct buffer_info));
  37         if(buf == NULL) {
  38                 ERR("add_buffer: insufficient memory");
  39                 return -1;
  40         }
  41
  42         buf->name = bufname;
  43         buf->pid = pid;
  44
  45         /* get shmid */
  46         asprintf(&send_msg, "get_shmid %s", buf->name);
  47         send_message(pid, send_msg, &received_msg);
  48         free(send_msg);
  49         DBG("got buffer name %s", buf->name);
  50
  51         result = sscanf(received_msg, "%d", &buf->shmid);
  52         if(result != 1) {
  53                 ERR("unable to parse response to get_shmid");
  54                 return -1;
  55         }
  56         free(received_msg);
  57         DBG("got shmid %d", buf->shmid);
  58
  59         /* get n_subbufs */
  60         asprintf(&send_msg, "get_n_subbufs %s", buf->name);
  61         send_message(pid, send_msg, &received_msg);
  62         free(send_msg);
  63
  64         result = sscanf(received_msg, "%d", &buf->n_subbufs);
  65         if(result != 1) {
  66                 ERR("unable to parse response to get_n_subbufs");
  67                 return -1;
  68         }
  69         free(received_msg);
  70         DBG("got n_subbufs %d", buf->n_subbufs);
  71
  72         /* get subbuf size */
  73         asprintf(&send_msg, "get_subbuf_size %s", buf->name);
  74         send_message(pid, send_msg, &received_msg);
  75         free(send_msg);
  76
  77         result = sscanf(received_msg, "%d", &buf->subbuf_size);
  78         if(result != 1) {
  79                 ERR("unable to parse response to get_subbuf_size");
  80                 return -1;
  81         }
  82         free(received_msg);
  83         DBG("got subbuf_size %d", buf->subbuf_size);
  84
  85         /* attach memory */
  86         buf->mem = shmat(buf->shmid, NULL, 0);
  87         if(buf->mem == (void *) 0) {
  88                 perror("shmat");
  89                 return -1;
  90         }
  91         DBG("successfully attached memory");
  92
  93         return 0;
  94 }
  95
  96 int main(int argc, char **argv)
  97 {
  98         struct ustcomm_ustd ustd;
  99         int result;
 100
 101         result = ustcomm_init_ustd(&ustd);
 102         if(result == -1) {
 103                 ERR("failed to initialize socket");
 104                 return 1;
 105         }
 106
 107         for(;;) {
 108                 char *recvbuf;
 109
 110                 ustcomm_ustd_recv_message(&ustd, &recvbuf, NULL);
 111
 112                 if(!strncmp(recvbuf, "collect", 7)) {
 113                         pid_t pid;
 114                         char *bufname;
 115                         int result;
 116
 117                         result = sscanf(recvbuf, "%*s %d %50as", &pid, &bufname);
 118                         if(result != 2) {
 119                                 fprintf(stderr, "parsing error: %s\n", recvbuf);
 120                         }
 121
 122                         add_buffer(pid, bufname);
 123
 124                 }
 125
 126                 free(recvbuf);
 127         }
 128
 129         return 0;
 130 }