tape390/tape390_common.c

   1 /*************************************************************************
   2  *
   3  * File...........: s390-tools/tape390/tape390_common.c
   4  * Author(s)......: Frank Munzert <munzert@de.ibm.com>
   5  *                  Michael Holzheu <holzheu@de.ibm.com>
   6  *
   7  * Copyright IBM Corp. 2006,2007
   8  *
   9  *************************************************************************/
  10
  11 #include <sys/stat.h>
  12 #include <stdio.h>
  13 #include <fcntl.h>
  14 #include <stdlib.h>
  15 #include <string.h>
  16 #include "tape390_common.h"
  17
  18 #define PROC_DEVICES_FILE "/proc/devices"
  19 #define PROC_DEVICES_FILE_WIDTH 100
  20
  21 char *prog_name;        /* Name of tool */
  22
  23 /*
  24  * Set name of tool
  25  */
  26 void set_prog_name(char *name)
  27 {
  28         prog_name = name;
  29 }
  30
  31 /*
  32  * Check whether specified device node is tape device
  33  */
  34 int is_not_tape(char *device)
  35 {
  36         FILE* fh;
  37         char line[PROC_DEVICES_FILE_WIDTH];
  38         char last_line[PROC_DEVICES_FILE_WIDTH];
  39         int found = 0;
  40         struct stat stat_struct;
  41
  42         if (stat(device, &stat_struct)) {
  43                 ERRMSG("%s: Unable to get device status for "
  44                        "'%s'. \n", prog_name, device);
  45                 perror("");
  46                 return 1;
  47         }
  48         fh = fopen(PROC_DEVICES_FILE,"r");
  49         if (!fh) {
  50                 ERRMSG("%s: WARNING: Cannot check for tape in file "
  51                        PROC_DEVICES_FILE ".\n", prog_name);
  52                 perror("");
  53                 return(0); /* check not possible, just continue */
  54         }
  55         while (!found && (fscanf(fh, "%s", line) != EOF)) {
  56                 if (strcmp(line, "tape") == 0)
  57                         found = 1;
  58                 else
  59                         strcpy(last_line, line);
  60         }
  61         fclose(fh);
  62         if (found && (major(stat_struct.st_rdev) ==
  63                       (unsigned int) atoi(last_line)))
  64                 return (0);
  65         else {
  66                 ERRMSG("%s: '%s' is not a tape device. \n", prog_name, device);
  67                 return 1;
  68         }
  69 }
  70
  71 /*
  72  * Open the tape device
  73  */
  74 int open_tape(char *device)
  75 {
  76         int fd;
  77         fd = open(device,O_RDONLY);
  78         if (fd < 0) {
  79                 ERRMSG("%s: Cannot open device %s.\n",
  80                         prog_name,device);
  81                 perror("");
  82                 exit(EXIT_MISUSE);
  83         }
  84         return fd;
  85 }