Merge branch 'refs/heads/t/portable_io'

[paraslash.git] / ipc.c

diff --git a/ipc.c b/ipc.c
index b8a6fd0c3733d16faa0f35179329d563381c9ec8..3cc5c15695a76c0442b1ceb4da889c6f5b2baeb1 100644 (file)
--- a/ipc.c
+++ b/ipc.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2006-2014 Andre Noll <maan@systemlinux.org>
+ * Copyright (C) 2006 Andre Noll <maan@tuebingen.mpg.de>
  *
  * Licensed under the GPL v2. For licencing details see COPYING.
  */
@@ -68,7 +68,7 @@ static void para_semop(int id, struct sembuf *sops, int num)
  *
  * This function either succeeds or aborts.
  *
- * \sa semop(2), struct misc_meta_data.
+ * \sa semop(2), struct \ref misc_meta_data.
  */
 void mutex_lock(int id)
 {
@@ -94,7 +94,7 @@ void mutex_lock(int id)
  *
  * This function either succeeds or aborts.
  *
- * \sa semop(2), struct misc_meta_data.
+ * \sa semop(2), struct \ref misc_meta_data.
  */
 void mutex_unlock(int id)
 {
@@ -161,6 +161,27 @@ int shm_attach(int id, enum shm_attach_mode mode, void **result)
        return *result == (void *) -1? -ERRNO_TO_PARA_ERROR(errno) : 1;
 }
 
+/**
+ * Get the size of a shared memory segment.
+ *
+ * \param id The shared memory segment identifier.
+ * \param result Size in bytes is returned here, zero on errors.
+ *
+ * \return Standard.
+ *
+ * \sa shmctl(2).
+ */
+int shm_size(int id, size_t *result)
+{
+       struct shmid_ds ds; /* data structure */
+
+       *result = 0;
+       if (shmctl(id, IPC_STAT, &ds) < 0)
+               return -ERRNO_TO_PARA_ERROR(errno);
+       *result = ds.shm_segsz;
+       return 1;
+}
+
 /**
  * Detach a shared memory segment.
  *