src/functional/ipc_shm.c

   1 #ifndef _XOPEN_SOURCE
   2 #define _XOPEN_SOURCE 700
   3 #endif
   4 #include <errno.h>
   5 #include <stdlib.h>
   6 #include <string.h>
   7 #include <time.h>
   8 #include <sys/types.h>
   9 #include <sys/shm.h>
  10 #include <sys/wait.h>
  11 #include <unistd.h>
  12 #include "test.h"
  13
  14 static const char path[] = ".";
  15 static const int id = 'h';
  16
  17 #define T(f) do{ \
  18         if ((f)+1 == 0) \
  19                 t_error("%s failed: %s\n", #f, strerror(errno)); \
  20 }while(0)
  21
  22 #define EQ(a,b,fmt) do{ \
  23         if ((a) != (b)) \
  24                 t_error("%s == %s failed: " fmt "\n", #a, #b, a, b); \
  25 }while(0)
  26
  27 static void set()
  28 {
  29         time_t t;
  30         key_t k;
  31         int shmid;
  32         struct shmid_ds shmid_ds;
  33         void *p;
  34
  35         T(t = time(0));
  36         T(k = ftok(path, id));
  37
  38         /* make sure we get a clean shared memory id */
  39         T(shmid = shmget(k, 100, IPC_CREAT|0666));
  40         T(shmctl(shmid, IPC_RMID, 0));
  41         T(shmid = shmget(k, 100, IPC_CREAT|IPC_EXCL|0666));
  42
  43         if (t_status)
  44                 exit(t_status);
  45
  46         /* check IPC_EXCL */
  47         errno = 0;
  48         if (shmget(k, 100, IPC_CREAT|IPC_EXCL|0666) != -1 || errno != EEXIST)
  49                 t_error("shmget(IPC_CREAT|IPC_EXCL) should have failed with EEXIST, got %s\n", strerror(errno));
  50
  51         /* check if shmget initilaized the msshmid_ds structure correctly */
  52         T(shmctl(shmid, IPC_STAT, &shmid_ds));
  53         EQ(shmid_ds.shm_perm.cuid, geteuid(), "got %d, want %d");
  54         EQ(shmid_ds.shm_perm.uid, geteuid(), "got %d, want %d");
  55         EQ(shmid_ds.shm_perm.cgid, getegid(), "got %d, want %d");
  56         EQ(shmid_ds.shm_perm.gid, getegid(), "got %d, want %d");
  57         EQ(shmid_ds.shm_perm.mode & 0x1ff, 0666, "got %o, want %o");
  58         EQ(shmid_ds.shm_segsz, 100, "got %d, want %d");
  59         EQ(shmid_ds.shm_lpid, 0, "got %d, want %d");
  60         EQ(shmid_ds.shm_cpid, getpid(), "got %d, want %d");
  61         EQ((int)shmid_ds.shm_nattch, 0, "got %d, want %d");
  62         EQ((long)shmid_ds.shm_atime, 0, "got %ld, want %d");
  63         EQ((long)shmid_ds.shm_dtime, 0, "got %ld, want %d");
  64         if (shmid_ds.shm_ctime < t)
  65                 t_error("shmid_ds.shm_ctime >= t failed: got %ld, want >= %ld\n", (long)shmid_ds.shm_ctime, (long)t);
  66         if (shmid_ds.shm_ctime > t+5)
  67                 t_error("shmid_ds.shm_ctime <= t+5 failed: got %ld, want <= %ld\n", (long)shmid_ds.shm_ctime, (long)t+5);
  68
  69         /* test attach */
  70         if ((p=shmat(shmid, 0, 0)) == 0)
  71                 t_error("shmat failed: %s\n", strerror(errno));
  72         T(shmctl(shmid, IPC_STAT, &shmid_ds));
  73         EQ((int)shmid_ds.shm_nattch, 1, "got %d, want %d");
  74         EQ(shmid_ds.shm_lpid, getpid(), "got %d, want %d");
  75         if (shmid_ds.shm_atime < t)
  76                 t_error("shm_atime is %ld want >= %ld\n", (long)shmid_ds.shm_atime, (long)t);
  77         if (shmid_ds.shm_atime > t+5)
  78                 t_error("shm_atime is %ld want <= %ld\n", (long)shmid_ds.shm_atime, (long)t+5);
  79         strcpy(p, "test data");
  80         T(shmdt(p));
  81 }
  82
  83 static void get()
  84 {
  85         key_t k;
  86         int shmid;
  87         void *p;
  88
  89         T(k = ftok(path, id));
  90         T(shmid = shmget(k, 0, 0));
  91
  92         errno = 0;
  93         if ((p=shmat(shmid, 0, SHM_RDONLY)) == 0)
  94                 t_error("shmat failed: %s\n", strerror(errno));
  95
  96         if (strcmp(p, "test data") != 0)
  97                 t_error("reading shared mem failed: got \"%.100s\" want \"test data\"\n", p);
  98
  99         /* cleanup */
 100         T(shmdt(p));
 101         T(shmctl(shmid, IPC_RMID, 0));
 102 }
 103
 104 int main(void)
 105 {
 106         int p;
 107         int status;
 108
 109         set();
 110         p = fork();
 111         if (p == -1)
 112                 t_error("fork failed: %s\n", strerror(errno));
 113         else if (p == 0)
 114                 get();
 115         else {
 116                 T(waitpid(p, &status, 0));
 117                 if (!WIFEXITED(status) || WEXITSTATUS(status) != 0)
 118                         t_error("child exit status: %d\n", status);
 119         }
 120         return t_status;
 121 }