diff options
Diffstat (limited to 'libjack/shm.c')
| -rw-r--r-- | libjack/shm.c | 205 |
1 files changed, 106 insertions, 99 deletions
diff --git a/libjack/shm.c b/libjack/shm.c index f3401c7..c5e24f2 100644 --- a/libjack/shm.c +++ b/libjack/shm.c @@ -12,22 +12,22 @@ /* Copyright (C) 2001-2003 Paul Davis - + This program is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. - + This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. - + You should have received a copy of the GNU Lesser General Public License - along with this program; if not, write to the Free Software + along with this program; if not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. - -*/ + + */ #include <config.h> @@ -58,13 +58,13 @@ static jack_shmtype_t jack_shmtype = shm_SYSV; #endif /* interface-dependent forward declarations */ -static int jack_access_registry (jack_shm_info_t *ri); -static int jack_create_registry (jack_shm_info_t *ri); -static void jack_remove_shm (jack_shm_id_t *id); +static int jack_access_registry(jack_shm_info_t *ri); +static int jack_create_registry(jack_shm_info_t *ri); +static void jack_remove_shm(jack_shm_id_t *id); /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * - * common interface-independent section - * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */ +* common interface-independent section +* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */ /* The JACK SHM registry is a chunk of memory for keeping track of the * shared memory used by each active JACK server. This allows the @@ -74,10 +74,10 @@ static void jack_remove_shm (jack_shm_id_t *id); */ /* per-process global data for the SHM interfaces */ -static jack_shm_id_t registry_id; /* SHM id for the registry */ -static jack_shm_info_t registry_info = { /* SHM info for the registry */ - .index = JACK_SHM_NULL_INDEX, - .attached_at = MAP_FAILED +static jack_shm_id_t registry_id; /* SHM id for the registry */ +static jack_shm_info_t registry_info = { /* SHM info for the registry */ + .index = JACK_SHM_NULL_INDEX, + .attached_at = MAP_FAILED }; /* pointers to registry header and array */ @@ -121,29 +121,29 @@ semaphore_init () key_t semkey = JACK_SEMAPHORE_KEY; struct sembuf sbuf; int create_flags = IPC_CREAT | IPC_EXCL - | S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH; + | S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH; /* Get semaphore ID associated with this key. */ - if ((semid = semget(semkey, 0, 0)) == -1) { + if ((semid = semget (semkey, 0, 0)) == -1) { /* Semaphore does not exist - Create. */ - if ((semid = semget(semkey, 1, create_flags)) != -1) { + if ((semid = semget (semkey, 1, create_flags)) != -1) { /* Initialize the semaphore, allow one owner. */ sbuf.sem_num = 0; sbuf.sem_op = 1; sbuf.sem_flg = 0; - if (semop(semid, &sbuf, 1) == -1) { + if (semop (semid, &sbuf, 1) == -1) { semaphore_error ("semop"); } } else if (errno == EEXIST) { - if ((semid = semget(semkey, 0, 0)) == -1) { + if ((semid = semget (semkey, 0, 0)) == -1) { semaphore_error ("semget"); } } else { - semaphore_error ("semget creation"); + semaphore_error ("semget creation"); } } } @@ -156,21 +156,22 @@ semaphore_add (int value) sbuf.sem_num = 0; sbuf.sem_op = value; sbuf.sem_flg = SEM_UNDO; - if (semop(semid, &sbuf, 1) == -1) { + if (semop (semid, &sbuf, 1) == -1) { semaphore_error ("semop"); } } -static void +static void jack_shm_lock_registry (void) { - if (semid == -1) + if (semid == -1) { semaphore_init (); + } semaphore_add (-1); } -static void +static void jack_shm_unlock_registry (void) { semaphore_add (1); @@ -188,12 +189,11 @@ jack_shm_init_registry () jack_shm_header->protocol = jack_protocol_version; jack_shm_header->type = jack_shmtype; jack_shm_header->size = JACK_SHM_REGISTRY_SIZE; - jack_shm_header->hdr_len = sizeof (jack_shm_header_t); - jack_shm_header->entry_len = sizeof (jack_shm_registry_t); + jack_shm_header->hdr_len = sizeof(jack_shm_header_t); + jack_shm_header->entry_len = sizeof(jack_shm_registry_t); - for (i = 0; i < MAX_SHM_ID; ++i) { + for (i = 0; i < MAX_SHM_ID; ++i) jack_shm_registry[i].index = i; - } } static int @@ -205,10 +205,10 @@ jack_shm_validate_registry () && (jack_shm_header->protocol == jack_protocol_version) && (jack_shm_header->type == jack_shmtype) && (jack_shm_header->size == JACK_SHM_REGISTRY_SIZE) - && (jack_shm_header->hdr_len == sizeof (jack_shm_header_t)) - && (jack_shm_header->entry_len == sizeof (jack_shm_registry_t))) { + && (jack_shm_header->hdr_len == sizeof(jack_shm_header_t)) + && (jack_shm_header->entry_len == sizeof(jack_shm_registry_t))) { - return 0; /* registry OK */ + return 0; /* registry OK */ } return -1; @@ -233,7 +233,7 @@ jack_shm_validate_registry () static void jack_set_server_prefix (const char *server_name) { - snprintf (jack_shm_server_prefix, sizeof (jack_shm_server_prefix), + snprintf (jack_shm_server_prefix, sizeof(jack_shm_server_prefix), "/jack-%d:%s:", getuid (), server_name); } @@ -246,9 +246,10 @@ jack_server_initialize_shm (int new_registry) { int rc; - if (jack_shm_header) - return 0; /* already initialized */ + if (jack_shm_header) { + return 0; /* already initialized */ + } jack_shm_lock_registry (); rc = jack_access_registry (®istry_info); @@ -259,14 +260,15 @@ jack_server_initialize_shm (int new_registry) } switch (rc) { - case ENOENT: /* registry does not exist */ + case ENOENT: /* registry does not exist */ rc = jack_create_registry (®istry_info); break; - case 0: /* existing registry */ - if (jack_shm_validate_registry () == 0) + case 0: /* existing registry */ + if (jack_shm_validate_registry () == 0) { break; - /* else it was invalid, so fall through */ - case EINVAL: /* bad registry */ + } + /* else it was invalid, so fall through */ + case EINVAL: /* bad registry */ /* Apparently, this registry was created by an older * JACK version. Delete it so we can try again. */ jack_release_shm (®istry_info); @@ -280,7 +282,7 @@ jack_server_initialize_shm (int new_registry) #endif } break; - default: /* failure return code */ + default: /* failure return code */ break; } @@ -300,9 +302,10 @@ jack_initialize_shm (const char *server_name) { int rc; - if (jack_shm_header) - return 0; /* already initialized */ + if (jack_shm_header) { + return 0; /* already initialized */ + } jack_set_server_prefix (server_name); jack_shm_lock_registry (); @@ -322,9 +325,10 @@ void jack_destroy_shm (jack_shm_info_t* si) { /* must NOT have the registry locked */ - if (si->index == JACK_SHM_NULL_INDEX) - return; /* segment not allocated */ + if (si->index == JACK_SHM_NULL_INDEX) { + return; /* segment not allocated */ + } jack_remove_shm (&jack_shm_registry[si->index].id); jack_release_shm_info (si->index); } @@ -341,7 +345,7 @@ jack_get_free_shm_info () break; } } - + if (i < MAX_SHM_ID) { si = &jack_shm_registry[i]; } @@ -356,21 +360,21 @@ jack_release_shm_entry (jack_shm_registry_index_t index) jack_shm_registry[index].size = 0; jack_shm_registry[index].allocator = 0; memset (&jack_shm_registry[index].id, 0, - sizeof (jack_shm_registry[index].id)); + sizeof(jack_shm_registry[index].id)); } void jack_release_shm_info (jack_shm_registry_index_t index) { /* must NOT have the registry locked */ - if (jack_shm_registry[index].allocator == getpid()) { + if (jack_shm_registry[index].allocator == getpid ()) { jack_shm_lock_registry (); jack_release_shm_entry (index); jack_shm_unlock_registry (); } } -/* Claim server_name for this process. +/* Claim server_name for this process. * * returns 0 if successful * EEXIST if server_name was already active for this user @@ -387,8 +391,9 @@ jack_register_server (const char *server_name, int new_registry) jack_info ("JACK compiled with %s SHM support.", JACK_SHM_TYPE); - if (jack_server_initialize_shm (new_registry)) + if (jack_server_initialize_shm (new_registry)) { return ENOMEM; + } jack_shm_lock_registry (); @@ -399,34 +404,35 @@ jack_register_server (const char *server_name, int new_registry) if (strncmp (jack_shm_header->server[i].name, jack_shm_server_prefix, - JACK_SERVER_NAME_SIZE) != 0) - continue; /* no match */ + JACK_SERVER_NAME_SIZE) != 0) { + continue; /* no match */ + } if (jack_shm_header->server[i].pid == my_pid) { jack_shm_unlock_registry (); - return 0; /* it's me */ + return 0; /* it's me */ } /* see if server still exists */ if (kill (jack_shm_header->server[i].pid, 0) == 0) { jack_shm_unlock_registry (); - return EEXIST; /* other server running */ + return EEXIST; /* other server running */ } /* it's gone, reclaim this entry */ memset (&jack_shm_header->server[i], 0, - sizeof (jack_shm_server_t)); + sizeof(jack_shm_server_t)); } /* find a free entry */ - for (i = 0; i < MAX_SERVERS; i++) { - if (jack_shm_header->server[i].pid == 0) + for (i = 0; i < MAX_SERVERS; i++) + if (jack_shm_header->server[i].pid == 0) { break; - } + } if (i >= MAX_SERVERS) { jack_shm_unlock_registry (); - return ENOSPC; /* out of space */ + return ENOSPC; /* out of space */ } /* claim it */ @@ -452,7 +458,7 @@ jack_unregister_server (const char *server_name /* unused */) for (i = 0; i < MAX_SERVERS; i++) { if (jack_shm_header->server[i].pid == my_pid) { memset (&jack_shm_header->server[i], 0, - sizeof (jack_shm_server_t)); + sizeof(jack_shm_server_t)); } } @@ -469,22 +475,23 @@ jack_cleanup_shm () pid_t my_pid = getpid (); jack_shm_lock_registry (); - + for (i = 0; i < MAX_SHM_ID; i++) { jack_shm_registry_t* r; r = &jack_shm_registry[i]; - memcpy (©, r, sizeof (jack_shm_info_t)); + memcpy (©, r, sizeof(jack_shm_info_t)); destroy = FALSE; /* ignore unused entries */ - if (r->allocator == 0) + if (r->allocator == 0) { continue; + } /* is this my shm segment? */ if (r->allocator == my_pid) { - /* allocated by this process, so unattach + /* allocated by this process, so unattach and destroy. */ jack_release_shm (©); destroy = TRUE; @@ -552,8 +559,8 @@ jack_resize_shm (jack_shm_info_t* si, jack_shmsize_t size) #ifdef USE_POSIX_SHM /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * - * POSIX interface-dependent functions - * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */ +* POSIX interface-dependent functions +* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */ /* gain addressability to existing SHM registry segment * @@ -569,7 +576,7 @@ jack_access_registry (jack_shm_info_t *ri) /* registry must be locked */ int shm_fd; - strncpy (registry_id, "/jack-shm-registry", sizeof (registry_id)); + strncpy (registry_id, "/jack-shm-registry", sizeof(registry_id)); /* try to open an existing segment */ if ((shm_fd = shm_open (registry_id, O_RDWR, 0666)) < 0) { @@ -583,7 +590,7 @@ jack_access_registry (jack_shm_info_t *ri) } if ((ri->attached_at = mmap (0, JACK_SHM_REGISTRY_SIZE, - PROT_READ|PROT_WRITE, + PROT_READ | PROT_WRITE, MAP_SHARED, shm_fd, 0)) == MAP_FAILED) { jack_error ("cannot mmap shm registry segment (%s)", strerror (errno)); @@ -594,7 +601,7 @@ jack_access_registry (jack_shm_info_t *ri) /* set up global pointers */ ri->index = JACK_SHM_REGISTRY_INDEX; jack_shm_header = ri->attached_at; - jack_shm_registry = (jack_shm_registry_t *) (jack_shm_header + 1); + jack_shm_registry = (jack_shm_registry_t*)(jack_shm_header + 1); return 0; } @@ -612,9 +619,9 @@ jack_create_registry (jack_shm_info_t *ri) /* registry must be locked */ int shm_fd; - strncpy (registry_id, "/jack-shm-registry", sizeof (registry_id)); + strncpy (registry_id, "/jack-shm-registry", sizeof(registry_id)); - if ((shm_fd = shm_open (registry_id, O_RDWR|O_CREAT, 0666)) < 0) { + if ((shm_fd = shm_open (registry_id, O_RDWR | O_CREAT, 0666)) < 0) { int rc = errno; jack_error ("cannot create shm registry segment (%s)", strerror (errno)); @@ -633,7 +640,7 @@ jack_create_registry (jack_shm_info_t *ri) } if ((ri->attached_at = mmap (0, JACK_SHM_REGISTRY_SIZE, - PROT_READ|PROT_WRITE, + PROT_READ | PROT_WRITE, MAP_SHARED, shm_fd, 0)) == MAP_FAILED) { jack_error ("cannot mmap shm registry segment (%s)", strerror (errno)); @@ -645,7 +652,7 @@ jack_create_registry (jack_shm_info_t *ri) /* set up global pointers */ ri->index = JACK_SHM_REGISTRY_INDEX; jack_shm_header = ri->attached_at; - jack_shm_registry = (jack_shm_registry_t *) (jack_shm_header + 1); + jack_shm_registry = (jack_shm_registry_t*)(jack_shm_header + 1); /* initialize registry contents */ jack_shm_init_registry (); @@ -661,8 +668,8 @@ jack_remove_shm (jack_shm_id_t *id) the shm segment, so this failing is not an error. XXX it would be good to differentiate between these two conditions. - */ - shm_unlink ((char *) id); + */ + shm_unlink ((char*)id); } void @@ -681,7 +688,7 @@ jack_shmalloc (jack_shmsize_t size, jack_shm_info_t* si) jack_shm_registry_t* registry; int shm_fd; int rc = -1; - char name[SHM_NAME_MAX+1]; + char name[SHM_NAME_MAX + 1]; jack_shm_lock_registry (); @@ -697,14 +704,14 @@ jack_shmalloc (jack_shmsize_t size, jack_shm_info_t* si) * actual names. So, we construct a short name from the * registry index for uniqueness. */ - snprintf (name, sizeof (name), "/jack-%d", registry->index); + snprintf (name, sizeof(name), "/jack-%d", registry->index); - if (strlen (name) >= sizeof (registry->id)) { + if (strlen (name) >= sizeof(registry->id)) { jack_error ("shm segment name too long %s", name); goto unlock; } - if ((shm_fd = shm_open (name, O_RDWR|O_CREAT, 0666)) < 0) { + if ((shm_fd = shm_open (name, O_RDWR | O_CREAT, 0666)) < 0) { jack_error ("cannot create shm segment %s (%s)", name, strerror (errno)); goto unlock; @@ -720,13 +727,13 @@ jack_shmalloc (jack_shmsize_t size, jack_shm_info_t* si) close (shm_fd); registry->size = size; - strncpy (registry->id, name, sizeof (registry->id)); - registry->allocator = getpid(); + strncpy (registry->id, name, sizeof(registry->id)); + registry->allocator = getpid (); si->index = registry->index; - si->attached_at = MAP_FAILED; /* not attached */ - rc = 0; /* success */ + si->attached_at = MAP_FAILED; /* not attached */ + rc = 0; /* success */ - unlock: +unlock: jack_shm_unlock_registry (); return rc; } @@ -744,9 +751,9 @@ jack_attach_shm (jack_shm_info_t* si) return -1; } - if ((si->attached_at = mmap (0, registry->size, PROT_READ|PROT_WRITE, + if ((si->attached_at = mmap (0, registry->size, PROT_READ | PROT_WRITE, MAP_SHARED, shm_fd, 0)) == MAP_FAILED) { - jack_error ("cannot mmap shm segment %s (%s)", + jack_error ("cannot mmap shm segment %s (%s)", registry->id, strerror (errno)); close (shm_fd); @@ -761,8 +768,8 @@ jack_attach_shm (jack_shm_info_t* si) #else /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * - * System V interface-dependent functions - * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */ +* System V interface-dependent functions +* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */ /* gain addressability to existing SHM registry segment * @@ -784,15 +791,15 @@ jack_access_registry (jack_shm_info_t *ri) switch (errno) { - case ENOENT: /* segment does not exist */ + case ENOENT: /* segment does not exist */ return ENOENT; - case EINVAL: /* segment exists, but too small */ + case EINVAL: /* segment exists, but too small */ /* attempt minimum size access */ registry_id = shmget (JACK_SHM_REGISTRY_KEY, 1, 0666); return EINVAL; - default: /* or other error */ + default: /* or other error */ jack_error ("unable to access shm registry (%s)", strerror (errno)); return errno; @@ -808,7 +815,7 @@ jack_access_registry (jack_shm_info_t *ri) /* set up global pointers */ ri->index = JACK_SHM_REGISTRY_INDEX; jack_shm_header = ri->attached_at; - jack_shm_registry = (jack_shm_registry_t *) (jack_shm_header + 1); + jack_shm_registry = (jack_shm_registry_t*)(jack_shm_header + 1); return 0; } @@ -826,7 +833,7 @@ jack_create_registry (jack_shm_info_t *ri) /* registry must be locked */ if ((registry_id = shmget (JACK_SHM_REGISTRY_KEY, JACK_SHM_REGISTRY_SIZE, - 0666|IPC_CREAT)) < 0) { + 0666 | IPC_CREAT)) < 0) { jack_error ("cannot create shm registry segment (%s)", strerror (errno)); return errno; @@ -841,7 +848,7 @@ jack_create_registry (jack_shm_info_t *ri) /* set up global pointers */ ri->index = JACK_SHM_REGISTRY_INDEX; jack_shm_header = ri->attached_at; - jack_shm_registry = (jack_shm_registry_t *) (jack_shm_header + 1); + jack_shm_registry = (jack_shm_registry_t*)(jack_shm_header + 1); /* initialize registry contents */ jack_shm_init_registry (); @@ -853,11 +860,11 @@ static void jack_remove_shm (jack_shm_id_t *id) { /* registry may or may not be locked */ - /* this call can fail if we are attempting to + /* this call can fail if we are attempting to remove a segment that was already deleted - by the client. XXX i suppose the + by the client. XXX i suppose the function should take a "canfail" argument. - */ + */ shmctl (*id, IPC_RMID, NULL); } @@ -871,7 +878,7 @@ jack_release_shm (jack_shm_info_t* si) } int -jack_shmalloc (jack_shmsize_t size, jack_shm_info_t* si) +jack_shmalloc (jack_shmsize_t size, jack_shm_info_t* si) { int shmflags; int shmid; @@ -888,7 +895,7 @@ jack_shmalloc (jack_shmsize_t size, jack_shm_info_t* si) registry->size = size; registry->id = shmid; - registry->allocator = getpid(); + registry->allocator = getpid (); si->index = registry->index; si->attached_at = MAP_FAILED; /* not attached */ rc = 0; |