X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=blobdiff_plain;f=ipc.c;h=85013a636cb3a7f634d190d9044808454274efd8;hp=576bfe5bcd815ee296da0b56d49a7f3ea5d97e4e;hb=23dd2200dd4fc74025ae87f5c2127f3b0ff71e9b;hpb=b307a25ed895caa33684302b502e9e0e70dc78b7 diff --git a/ipc.c b/ipc.c index 576bfe5b..85013a63 100644 --- a/ipc.c +++ b/ipc.c @@ -1,8 +1,4 @@ -/* - * Copyright (C) 2006-2011 Andre Noll - * - * Licensed under the GPL v2. For licencing details see COPYING. - */ +/* Copyright (C) 2006 Andre Noll , see file COPYING. */ /** \file ipc.c Inter-process communication and shared memory helpers. */ @@ -68,7 +64,7 @@ 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 +90,7 @@ 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 +157,27 @@ 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. * @@ -209,6 +226,7 @@ size_t shm_get_shmmax(void) buf[ret] = '\0'; shmmax = strtoul(buf, NULL, 10); } + close(fd); } } #elif defined SYSCTL_SHMMAX_VARIABLE @@ -221,7 +239,7 @@ size_t shm_get_shmmax(void) #endif if (shmmax == 0) { PARA_WARNING_LOG("unable to determine shmmax\n"); - shmmax = 65535; /* last ressort */ + shmmax = 65535; /* last resort */ } PARA_INFO_LOG("shmmax: %zu\n", shmmax); return shmmax;