From: Szabolcs Nagy <nsz@port70.net>
Date: Wed, 24 Oct 2012 00:11:03 +0000 (+0200)
Subject: general: simple sysv ipc sem test
X-Git-Url: http://nsz.repo.hu/git/?p=libc-test;a=commitdiff_plain;h=dc1a7ecaaebc597a1f63d87d1c023bb82efda536

general: simple sysv ipc sem test
---

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 <errno.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#include <sys/types.h>
+#include <sys/sem.h>
+#include <sys/wait.h>
+#include <unistd.h>
+#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 <stdarg.h>
 #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, ...)