diff --git a/src/general/ipc_sem.c b/src/general/ipc_sem.c new file mode 100644 index 0000000..8f69586 --- /dev/null +++ b/src/general/ipc_sem.c @@ -0,0 +1,123 @@ +#ifndef _XOPEN_SOURCE +#define _XOPEN_SOURCE 700 +#endif +#include +#include +#include +#include +#include +#include +#include +#include +#include "test.h" + +static const char path[] = "."; +static const int id = 'x'; + +#define T(f) do{ \ + if ((f)+1 == 0) \ + error("%s failed: %s\n", #f, strerror(errno)); \ +}while(0) + +#define EQ(a,b,fmt) do{ \ + if ((a) != (b)) \ + error("%s == %s failed: " fmt "\n", #a, #b, a, b); \ +}while(0) + +static void inc() +{ + time_t t; + key_t k; + int semid, semval, sempid, semncnt, semzcnt; + struct semid_ds semid_ds; + union semun { + int val; + struct semid_ds *buf; + unsigned short *array; + } arg; + struct sembuf sops; + + T(t = time(0)); + T(k = ftok(path, id)); + + /* make sure we get a clean semaphore id */ + T(semid = semget(k, 1, IPC_CREAT|0666)); + T(semctl(semid, 0, IPC_RMID)); + T(semid = semget(k, 1, IPC_CREAT|IPC_EXCL|0666)); + + if (test_status) + exit(test_status); + + /* check IPC_EXCL */ + errno = 0; + if (semget(k, 1, IPC_CREAT|IPC_EXCL|0666) != -1 || errno != EEXIST) + error("semget(IPC_CREAT|IPC_EXCL) should have failed with EEXIST, got %s\n", strerror(errno)); + + /* check if msgget initilaized the msqid_ds structure correctly */ + arg.buf = &semid_ds; + T(semctl(semid, 0, IPC_STAT, arg)); + EQ(semid_ds.sem_perm.cuid, geteuid(), "got %d, want %d"); + EQ(semid_ds.sem_perm.uid, geteuid(), "got %d, want %d"); + EQ(semid_ds.sem_perm.cgid, getegid(), "got %d, want %d"); + EQ(semid_ds.sem_perm.gid, getegid(), "got %d, want %d"); + EQ(semid_ds.sem_perm.mode & 0x1ff, 0666, "got %o, want %o"); + EQ(semid_ds.sem_nsems, 1, "got %d, want %d"); + EQ((long)semid_ds.sem_otime, 0, "got %ld, want %d"); + if (semid_ds.sem_ctime < t) + error("semid_ds.sem_ctime >= t failed: got %ld, want %ld\n", (long)semid_ds.sem_ctime, (long)t); + + /* test sem_op > 0 */ + sops.sem_num = 0; + sops.sem_op = 1; + sops.sem_flg = 0; + T(semop(semid, &sops, 1)); + T(semval = semctl(semid, 0, GETVAL)); + EQ(semval, 1, "got %d, want %d"); + T(sempid = semctl(semid, 0, GETPID)); + EQ(sempid, getpid(), "got %d, want %d"); + T(semncnt = semctl(semid, 0, GETNCNT)); + EQ(semncnt, 0, "got %d, want %d"); + T(semzcnt = semctl(semid, 0, GETZCNT)); + EQ(semzcnt, 0, "got %d, want %d"); +} + +static void dec() +{ + key_t k; + int semid, semval; + struct sembuf sops; + + T(k = ftok(path, id)); + T(semid = semget(k, 0, 0)); + + /* test sem_op < 0 */ + sops.sem_num = 0; + sops.sem_op = -1; + sops.sem_flg = 0; + T(semop(semid, &sops, 1)); + T(semval = semctl(semid, 0, GETVAL)); + EQ(semval, 0, "got %d, want %d"); + + /* cleanup */ + T(semctl(semid, 0, IPC_RMID)); +} + +int main(void) +{ + int p; + int status; + + inc(); + p = fork(); + if (p == -1) + error("fork failed: %s\n", strerror(errno)); + else if (p == 0) + dec(); + else { + T(waitpid(p, &status, 0)); + if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) + error("child exit status: %d\n", status); + } + return test_status; +} + diff --git a/src/general/test.h b/src/general/test.h index a6a7706..a17c185 100644 --- a/src/general/test.h +++ b/src/general/test.h @@ -2,6 +2,7 @@ #include #define error(...) test_error(__FILE__, __LINE__, __VA_ARGS__) +/* TODO: not thread-safe nor fork-safe */ static int test_status; static int test_error(const char *n, int l, const char *s, ...)