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Diffstat (limited to 'src/lib/shm_du_map.c')
-rw-r--r--src/lib/shm_du_map.c767
1 files changed, 0 insertions, 767 deletions
diff --git a/src/lib/shm_du_map.c b/src/lib/shm_du_map.c
deleted file mode 100644
index 9ca282b9..00000000
--- a/src/lib/shm_du_map.c
+++ /dev/null
@@ -1,767 +0,0 @@
-/*
- * Ouroboros - Copyright (C) 2016
- *
- * Shared memory map for data units
- *
- * Dimitri Staessens <dimitri.staessens@intec.ugent.be>
- * Sander Vrijders <sander.vrijders@intec.ugent.be>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 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 General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
- */
-
-#include <ouroboros/config.h>
-#include <ouroboros/errno.h>
-#include <ouroboros/shm_du_map.h>
-#include <ouroboros/shm_ap_rbuff.h>
-#include <ouroboros/time_utils.h>
-
-#include <pthread.h>
-#include <sys/mman.h>
-#include <fcntl.h>
-#include <unistd.h>
-#include <stdlib.h>
-#include <string.h>
-#include <signal.h>
-#include <sys/stat.h>
-
-#define OUROBOROS_PREFIX "shm_du_map"
-
-#include <ouroboros/logs.h>
-
-#define SHM_BLOCKS_SIZE (SHM_BUFFER_SIZE * SHM_DU_BUFF_BLOCK_SIZE)
-#define SHM_FILE_SIZE (SHM_BLOCKS_SIZE + 3 * sizeof (size_t) \
- + sizeof(pthread_mutex_t) + 2 * sizeof(pthread_cond_t) \
- + sizeof(pid_t))
-
-#define get_head_ptr(dum) \
-((struct shm_du_buff *)(dum->shm_base + (*dum->ptr_head * \
- SHM_DU_BUFF_BLOCK_SIZE)))
-
-#define get_tail_ptr(dum) \
-((struct shm_du_buff *)(dum->shm_base + (*dum->ptr_tail * \
- SHM_DU_BUFF_BLOCK_SIZE)))
-
-#define idx_to_du_buff_ptr(dum, idx) \
- ((struct shm_du_buff *)(dum->shm_base + (idx * SHM_DU_BUFF_BLOCK_SIZE)))
-
-#define block_ptr_to_idx(dum, sdb) \
- (((uint8_t *)sdb - dum->shm_base) / SHM_DU_BUFF_BLOCK_SIZE)
-
-#define shm_map_used(dum)((*dum->ptr_head + SHM_BUFFER_SIZE - *dum->ptr_tail)\
- & (SHM_BUFFER_SIZE - 1))
-#define shm_map_free(dum, i)(shm_map_used(dum) + i < SHM_BUFFER_SIZE)
-
-#define shm_map_empty(dum) (*dum->ptr_tail == *dum->ptr_head)
-
-struct shm_du_buff {
- size_t size;
-#ifdef SHM_DU_MAP_MULTI_BLOCK
- size_t blocks;
-#endif
- size_t du_head;
- size_t du_tail;
- pid_t dst_api;
-};
-
-struct shm_du_map {
- uint8_t * shm_base; /* start of blocks */
- size_t * ptr_head; /* start of ringbuffer head */
- size_t * ptr_tail; /* start of ringbuffer tail */
- pthread_mutex_t * lock; /* lock all free space in shm */
- size_t * choked; /* stale sdu detection */
- pthread_cond_t * healthy; /* du map is healthy */
- pthread_cond_t * full; /* run sanitizer when buffer full */
- pid_t * api; /* api of the irmd owner */
- int fd;
-};
-
-static void garbage_collect(struct shm_du_map * dum)
-{
-#ifdef SHM_DU_MAP_MULTI_BLOCK
- struct shm_du_buff * sdb;
- while (!shm_map_empty(dum) && (sdb = get_tail_ptr(dum))->dst_api == -1)
- *dum->ptr_tail = (*dum->ptr_tail + sdb->blocks)
- & (SHM_BUFFER_SIZE - 1);
-#else
- while (!shm_map_empty(dum) && get_tail_ptr(dum)->dst_api == -1)
- *dum->ptr_tail =
- (*dum->ptr_tail + 1) & (SHM_BUFFER_SIZE - 1);
-
-#endif
-}
-
-static void clean_sdus(struct shm_du_map * dum, pid_t api, bool exit)
-{
- size_t idx = *dum->ptr_tail;
- struct shm_du_buff * buf;
-
- while (idx != *dum->ptr_head) {
- buf = idx_to_du_buff_ptr(dum, idx);
- if (buf->dst_api == api)
- buf->dst_api = -1;
-#ifdef SHM_DU_MAP_MULTI_BLOCK
- idx = (idx + buf->blocks) & (SHM_BUFFER_SIZE - 1);
-#else
- idx = (idx + 1) & (SHM_BUFFER_SIZE - 1);
-#endif
- }
-
- garbage_collect(dum);
-
- if (!exit && kill(api, 0) == 0) {
- struct shm_ap_rbuff * rb;
- rb = shm_ap_rbuff_open(api);
- if (rb != NULL) {
- shm_ap_rbuff_reset(rb);
- shm_ap_rbuff_close(rb);
- }
- }
-
- *dum->choked = 0;
-}
-
-struct shm_du_map * shm_du_map_create()
-{
- struct shm_du_map * dum;
- int shm_fd;
- uint8_t * shm_base;
- pthread_mutexattr_t mattr;
- pthread_condattr_t cattr;
-
- dum = malloc(sizeof *dum);
- if (dum == NULL) {
- LOG_DBGF("Could not allocate struct.");
- return NULL;
- }
-
- shm_fd = shm_open(SHM_DU_MAP_FILENAME, O_CREAT | O_EXCL | O_RDWR, 0666);
- if (shm_fd == -1) {
- LOG_DBGF("Failed creating shared memory map.");
- free(dum);
- return NULL;
- }
-
- if (fchmod(shm_fd, 0666)) {
- LOG_DBGF("Failed to chmod shared memory map.");
- free(dum);
- return NULL;
- }
-
- if (ftruncate(shm_fd, SHM_FILE_SIZE - 1) < 0) {
- LOG_DBGF("Failed to extend shared memory map.");
- free(dum);
- return NULL;
- }
-
- if (write(shm_fd, "", 1) != 1) {
- LOG_DBGF("Failed to finalise extension of shared memory map.");
- free(dum);
- return NULL;
- }
-
- shm_base = mmap(NULL,
- SHM_FILE_SIZE,
- PROT_READ | PROT_WRITE,
- MAP_SHARED,
- shm_fd,
- 0);
-
- if (shm_base == MAP_FAILED) {
- LOG_DBGF("Failed to map shared memory.");
- if (shm_unlink(SHM_DU_MAP_FILENAME) == -1)
- LOG_DBGF("Failed to remove invalid shm.");
-
- free(dum);
- return NULL;
- }
-
- dum->shm_base = shm_base;
- dum->ptr_head = (size_t *)
- ((uint8_t *) dum->shm_base + SHM_BLOCKS_SIZE);
- dum->ptr_tail = dum->ptr_head + 1;
- dum->lock = (pthread_mutex_t *) (dum->ptr_tail + 1);
- dum->choked = (size_t *) (dum->lock + 1);
- dum->healthy = (pthread_cond_t *) (dum->choked + 1);
- dum->full = dum->healthy + 1;
- dum->api = (pid_t *) (dum->full + 1);
-
- pthread_mutexattr_init(&mattr);
- pthread_mutexattr_setpshared(&mattr, PTHREAD_PROCESS_SHARED);
- pthread_mutexattr_setrobust(&mattr, PTHREAD_MUTEX_ROBUST);
- pthread_mutex_init(dum->lock, &mattr);
-
- pthread_condattr_init(&cattr);
- pthread_condattr_setpshared(&cattr, PTHREAD_PROCESS_SHARED);
- pthread_cond_init(dum->full, &cattr);
- pthread_cond_init(dum->healthy, &cattr);
-
- *dum->ptr_head = 0;
- *dum->ptr_tail = 0;
-
- *dum->choked = 0;
-
- *dum->api = getpid();
-
- dum->fd = shm_fd;
-
- return dum;
-}
-
-struct shm_du_map * shm_du_map_open()
-{
- struct shm_du_map * dum;
- int shm_fd;
- uint8_t * shm_base;
-
- dum = malloc(sizeof *dum);
- if (dum == NULL) {
- LOG_DBGF("Could not allocate struct.");
- return NULL;
- }
-
- shm_fd = shm_open(SHM_DU_MAP_FILENAME, O_RDWR, 0666);
- if (shm_fd < 0) {
- LOG_DBGF("Failed opening shared memory.");
- free(dum);
- return NULL;
- }
-
- shm_base = mmap(NULL,
- SHM_FILE_SIZE,
- PROT_READ | PROT_WRITE,
- MAP_SHARED,
- shm_fd,
- 0);
- if (shm_base == MAP_FAILED) {
- LOG_DBGF("Failed to map shared memory.");
- if (close(shm_fd) == -1)
- LOG_DBGF("Failed to close invalid shm.");
- if (shm_unlink(SHM_DU_MAP_FILENAME) == -1)
- LOG_DBGF("Failed to unlink invalid shm.");
- free(dum);
- return NULL;
- }
-
- dum->shm_base = shm_base;
- dum->ptr_head = (size_t *)
- ((uint8_t *) dum->shm_base + SHM_BLOCKS_SIZE);
- dum->ptr_tail = dum->ptr_head + 1;
- dum->lock = (pthread_mutex_t *) (dum->ptr_tail + 1);
- dum->choked = (size_t *) (dum->lock + 1);
- dum->healthy = (pthread_cond_t *) (dum->choked + 1);
- dum->full = dum->healthy + 1;
- dum->api = (pid_t *) (dum->full + 1);
-
- dum->fd = shm_fd;
-
- return dum;
-}
-
-void * shm_du_map_sanitize(void * o)
-{
- struct shm_du_map * dum = (struct shm_du_map *) o;
- struct timespec intv
- = {SHM_DU_TIMEOUT_MICROS / MILLION,
- (SHM_DU_TIMEOUT_MICROS % MILLION) * 1000};
-
- pid_t api;
-
- if (dum == NULL)
- return (void *) -1;
- if (pthread_mutex_lock(dum->lock) == EOWNERDEAD) {
- LOG_WARN("Recovering dead mutex.");
- pthread_mutex_consistent(dum->lock);
- }
-
- pthread_cleanup_push((void (*)(void *)) pthread_mutex_unlock,
- (void *) dum->lock);
-
- while (true) {
- int ret = 0;
- struct timespec now;
- struct timespec dl;
-
- if (pthread_cond_wait(dum->full, dum->lock) == EOWNERDEAD) {
- LOG_WARN("Recovering dead mutex.");
- pthread_mutex_consistent(dum->lock);
- }
-
- *dum->choked = 1;
-
- garbage_collect(dum);
-
- if (shm_map_empty(dum))
- continue;
-
- api = get_tail_ptr(dum)->dst_api;
-
- if (kill(api, 0)) {
- LOG_DBGF("Dead process %d left stale sdu.", api);
- clean_sdus(dum, api, false);
- continue;
- }
-
- clock_gettime(CLOCK_REALTIME, &now);
- ts_add(&now, &intv, &dl);
- while (*dum->choked) {
- ret = pthread_cond_timedwait(dum->healthy,
- dum->lock,
- &dl);
- if (!ret)
- continue;
-
- if (ret == EOWNERDEAD) {
- LOG_WARN("Recovering dead mutex.");
- pthread_mutex_consistent(dum->lock);
- }
-
- if (ret == ETIMEDOUT) {
- LOG_DBGF("SDU timed out (dst: %d).", api);
- clean_sdus(dum, api, false);
- }
- }
- }
-
- pthread_cleanup_pop(true);
-
- return (void *) 0;
-}
-
-void shm_du_map_close_on_exit(struct shm_du_map * dum)
-{
- if (dum == NULL) {
- LOG_DBGF("Bogus input. Bugging out.");
- return;
- }
-
- clean_sdus(dum, getpid(), true);
-
- if (close(dum->fd) < 0)
- LOG_DBGF("Couldn't close shared memory.");
-
- if (munmap(dum->shm_base, SHM_FILE_SIZE) == -1)
- LOG_DBGF("Couldn't unmap shared memory.");
-
- free(dum);
-}
-
-void shm_du_map_close(struct shm_du_map * dum)
-{
- if (dum == NULL) {
- LOG_DBGF("Bogus input. Bugging out.");
- return;
- }
-
- if (close(dum->fd) < 0)
- LOG_DBGF("Couldn't close shared memory.");
-
- if (munmap(dum->shm_base, SHM_FILE_SIZE) == -1)
- LOG_DBGF("Couldn't unmap shared memory.");
-
- free(dum);
-}
-
-void shm_du_map_destroy(struct shm_du_map * dum)
-{
- if (dum == NULL) {
- LOG_DBGF("Bogus input. Bugging out.");
- return;
- }
-
- if (getpid() != *dum->api && kill(*dum->api, 0) == 0) {
- LOG_DBGF("Only IRMd can destroy %s.", SHM_DU_MAP_FILENAME);
- return;
- }
-
- if (close(dum->fd) < 0)
- LOG_DBGF("Couldn't close shared memory.");
-
- if (munmap(dum->shm_base, SHM_FILE_SIZE) == -1)
- LOG_DBGF("Couldn't unmap shared memory.");
-
- if (shm_unlink(SHM_DU_MAP_FILENAME) == -1)
- LOG_DBGF("Failed to unlink shm.");
-
- free(dum);
-}
-
-ssize_t shm_du_map_write(struct shm_du_map * dum,
- pid_t dst_api,
- size_t headspace,
- size_t tailspace,
- uint8_t * data,
- size_t len)
-{
- struct shm_du_buff * sdb;
- size_t size = headspace + len + tailspace;
-#ifdef SHM_DU_MAP_MULTI_BLOCK
- long blocks = 0;
- long padblocks = 0;
-#endif
- int sz = size + sizeof *sdb;
- uint8_t * write_pos;
- ssize_t idx = -1;
-
- if (dum == NULL || data == NULL) {
- LOG_DBGF("Bogus input, bugging out.");
- return -1;
- }
-
-#ifndef SHM_DU_MAP_MULTI_BLOCK
- if (sz > SHM_DU_BUFF_BLOCK_SIZE) {
- LOG_DBGF("Multi-block SDU's disabled. Dropping.");
- return -1;
- }
-#endif
- if (pthread_mutex_lock(dum->lock) == EOWNERDEAD) {
- LOG_DBGF("Recovering dead mutex.");
- pthread_mutex_consistent(dum->lock);
- }
-#ifdef SHM_DU_MAP_MULTI_BLOCK
- while (sz > 0) {
- sz -= SHM_DU_BUFF_BLOCK_SIZE;
- ++blocks;
- }
-
- if (blocks + *dum->ptr_head > SHM_BUFFER_SIZE)
- padblocks = SHM_BUFFER_SIZE - *dum->ptr_head;
-
- if (!shm_map_free(dum, (blocks + padblocks))) {
-#else
- if (!shm_map_free(dum, 1)) {
-#endif
- pthread_cond_signal(dum->full);
- pthread_mutex_unlock(dum->lock);
- return -1;
- }
-
-#ifdef SHM_DU_MAP_MULTI_BLOCK
- if (padblocks) {
- sdb = get_head_ptr(dum);
- sdb->size = 0;
- sdb->blocks = padblocks;
- sdb->dst_api = -1;
- sdb->du_head = 0;
- sdb->du_tail = 0;
-
- *dum->ptr_head = 0;
- }
-#endif
- sdb = get_head_ptr(dum);
- sdb->size = size;
- sdb->dst_api = dst_api;
- sdb->du_head = headspace;
- sdb->du_tail = sdb->du_head + len;
-#ifdef SHM_DU_MAP_MULTI_BLOCK
- sdb->blocks = blocks;
-#endif
- write_pos = ((uint8_t *) (sdb + 1)) + headspace;
-
- memcpy(write_pos, data, len);
-
- idx = *dum->ptr_head;
-#ifdef SHM_DU_MAP_MULTI_BLOCK
- *dum->ptr_head = (*dum->ptr_head + blocks) & (SHM_BUFFER_SIZE - 1);
-#else
- *dum->ptr_head = (*dum->ptr_head + 1) & (SHM_BUFFER_SIZE - 1);
-#endif
- pthread_mutex_unlock(dum->lock);
-
- return idx;
-}
-
-ssize_t shm_du_map_write_b(struct shm_du_map * dum,
- pid_t dst_api,
- size_t headspace,
- size_t tailspace,
- uint8_t * data,
- size_t len)
-{
- struct shm_du_buff * sdb;
- size_t size = headspace + len + tailspace;
-#ifdef SHM_DU_MAP_MULTI_BLOCK
- long blocks = 0;
- long padblocks = 0;
-#endif
- int sz = size + sizeof *sdb;
- uint8_t * write_pos;
- ssize_t idx = -1;
-
- if (dum == NULL || data == NULL) {
- LOG_DBGF("Bogus input, bugging out.");
- return -1;
- }
-
-#ifndef SHM_DU_MAP_MULTI_BLOCK
- if (sz > SHM_DU_BUFF_BLOCK_SIZE) {
- LOG_DBGF("Multi-block SDU's disabled. Dropping.");
- return -1;
- }
-#endif
- if (pthread_mutex_lock(dum->lock) == EOWNERDEAD) {
- LOG_DBGF("Recovering dead mutex.");
- pthread_mutex_consistent(dum->lock);
- }
-
- pthread_cleanup_push((void(*)(void *))pthread_mutex_unlock,
- (void *) dum->lock);
-
-#ifdef SHM_DU_MAP_MULTI_BLOCK
- while (sz > 0) {
- sz -= SHM_DU_BUFF_BLOCK_SIZE;
- ++blocks;
- }
-
- if (blocks + *dum->ptr_head > SHM_BUFFER_SIZE)
- padblocks = SHM_BUFFER_SIZE - *dum->ptr_head;
-
- while (!shm_map_free(dum, (blocks + padblocks))) {
-#else
- while (!shm_map_free(dum, 1)) {
-#endif
- pthread_cond_signal(dum->full);
- pthread_cond_wait(dum->healthy, dum->lock);
- }
-
-#ifdef SHM_DU_MAP_MULTI_BLOCK
- if (padblocks) {
- sdb = get_head_ptr(dum);
- sdb->size = 0;
- sdb->blocks = padblocks;
- sdb->dst_api = -1;
- sdb->du_head = 0;
- sdb->du_tail = 0;
-
- *dum->ptr_head = 0;
- }
-#endif
- sdb = get_head_ptr(dum);
- sdb->size = size;
- sdb->dst_api = dst_api;
- sdb->du_head = headspace;
- sdb->du_tail = sdb->du_head + len;
-#ifdef SHM_DU_MAP_MULTI_BLOCK
- sdb->blocks = blocks;
-#endif
- write_pos = ((uint8_t *) (sdb + 1)) + headspace;
-
- memcpy(write_pos, data, len);
-
- idx = *dum->ptr_head;
-#ifdef SHM_DU_MAP_MULTI_BLOCK
- *dum->ptr_head = (*dum->ptr_head + blocks) & (SHM_BUFFER_SIZE - 1);
-#else
- *dum->ptr_head = (*dum->ptr_head + 1) & (SHM_BUFFER_SIZE - 1);
-#endif
- pthread_cleanup_pop(true);
-
- return idx;
-}
-
-int shm_du_map_read(uint8_t ** dst,
- struct shm_du_map * dum,
- ssize_t idx)
-{
- size_t len = 0;
- struct shm_du_buff * sdb;
-
- if (idx > SHM_BUFFER_SIZE)
- return -1;
-
- if (pthread_mutex_lock(dum->lock) == EOWNERDEAD) {
- LOG_DBGF("Recovering dead mutex.");
- pthread_mutex_consistent(dum->lock);
- }
-
- if (shm_map_empty(dum)) {
- pthread_mutex_unlock(dum->lock);
- return -1;
- }
-
- sdb = idx_to_du_buff_ptr(dum, idx);
- len = sdb->du_tail - sdb->du_head;
- *dst = ((uint8_t *) (sdb + 1)) + sdb->du_head;
-
- pthread_mutex_unlock(dum->lock);
-
- return len;
-}
-
-int shm_du_map_remove(struct shm_du_map * dum, ssize_t idx)
-{
- if (idx > SHM_BUFFER_SIZE)
- return -1;
-
- if (pthread_mutex_lock(dum->lock) == EOWNERDEAD) {
- LOG_DBGF("Recovering dead mutex.");
- pthread_mutex_consistent(dum->lock);
- }
-
- if (shm_map_empty(dum)) {
- pthread_mutex_unlock(dum->lock);
- return -1;
- }
-
- idx_to_du_buff_ptr(dum, idx)->dst_api = -1;
-
- if (idx != *dum->ptr_tail) {
- pthread_mutex_unlock(dum->lock);
- return 0;
- }
-
- garbage_collect(dum);
-
- *dum->choked = 0;
-
- pthread_cond_broadcast(dum->healthy);
-
- pthread_mutex_unlock(dum->lock);
-
- return 0;
-}
-
-uint8_t * shm_du_buff_head_alloc(struct shm_du_map * dum,
- int idx,
- ssize_t size)
-{
- struct shm_du_buff * sdb;
- uint8_t * buf;
-
- if (dum == NULL)
- return NULL;
-
- if (idx < 0 || idx > SHM_BUFFER_SIZE)
- return NULL;
-
- if (pthread_mutex_lock(dum->lock) == EOWNERDEAD) {
- LOG_DBGF("Recovering dead mutex.");
- pthread_mutex_consistent(dum->lock);
- }
-
- sdb = idx_to_du_buff_ptr(dum, idx);
-
- if ((long) (sdb->du_head - size) < 0) {
- pthread_mutex_unlock(dum->lock);
- LOG_DBGF("Failed to allocate PCI headspace.");
- return NULL;
- }
-
- sdb->du_head -= size;
-
- buf = (uint8_t *) (sdb + 1) + sdb->du_head;
-
- pthread_mutex_unlock(dum->lock);
-
- return buf;
-}
-
-uint8_t * shm_du_buff_tail_alloc(struct shm_du_map * dum,
- int idx,
- ssize_t size)
-{
- struct shm_du_buff * sdb;
- uint8_t * buf;
-
- if (dum == NULL)
- return NULL;
-
- if (idx < 0 || idx > SHM_BUFFER_SIZE)
- return NULL;
-
- if (pthread_mutex_lock(dum->lock) == EOWNERDEAD) {
- LOG_DBGF("Recovering dead mutex.");
- pthread_mutex_consistent(dum->lock);
- }
-
- sdb = idx_to_du_buff_ptr(dum, idx);
-
- if (sdb->du_tail + size >= sdb->size) {
- pthread_mutex_unlock(dum->lock);
- LOG_DBGF("Failed to allocate PCI tailspace.");
- return NULL;
- }
-
- buf = (uint8_t *) (sdb + 1) + sdb->du_tail;
-
- sdb->du_tail += size;
-
- pthread_mutex_unlock(dum->lock);
-
- return buf;
-}
-
-int shm_du_buff_head_release(struct shm_du_map * dum,
- int idx,
- ssize_t size)
-{
- struct shm_du_buff * sdb;
-
- if (dum == NULL)
- return -1;
-
- if (idx < 0 || idx > SHM_BUFFER_SIZE)
- return -1;
-
- if (pthread_mutex_lock(dum->lock) == EOWNERDEAD) {
- LOG_DBGF("Recovering dead mutex.");
- pthread_mutex_consistent(dum->lock);
- }
-
- sdb = idx_to_du_buff_ptr(dum, idx);
-
- if (size > sdb->du_tail - sdb->du_head) {
- pthread_mutex_unlock(dum->lock);
- LOG_DBGF("Tried to release beyond sdu boundary.");
- return -EOVERFLOW;
- }
-
- sdb->du_head += size;
-
- pthread_mutex_unlock(dum->lock);
-
- return 0;
-}
-
-int shm_du_buff_tail_release(struct shm_du_map * dum,
- int idx,
- ssize_t size)
-{
- struct shm_du_buff * sdb;
-
- if (dum == NULL)
- return -1;
-
- if (idx < 0 || idx > SHM_BUFFER_SIZE)
- return -1;
-
- if (pthread_mutex_lock(dum->lock) == EOWNERDEAD) {
- LOG_DBGF("Recovering dead mutex.");
- pthread_mutex_consistent(dum->lock);
- }
-
- sdb = idx_to_du_buff_ptr(dum, idx);
-
- if (size > sdb->du_tail - sdb->du_head) {
- pthread_mutex_unlock(dum->lock);
- LOG_DBGF("Tried to release beyond sdu boundary.");
- return -EOVERFLOW;
- }
-
- sdb->du_tail -= size;
-
- pthread_mutex_unlock(dum->lock);
-
- return 0;
-}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-01 23:08:44 +0000