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authordimitri staessens <dimitri.staessens@intec.ugent.be>2016-08-30 21:25:23 +0200
committerdimitri staessens <dimitri.staessens@intec.ugent.be>2016-08-30 21:25:23 +0200
commit1071824054828b9be36f50416f858c49c9acd701 (patch)
tree303d3d61717d4d3018b8025a9825ff799da01c08 /src/lib/shm_rdrbuff.c
parent11ae1b5669356fbaf3405e77d36f517f8c1894cc (diff)
parent52db4952d80a10aae464274acdd7401267818b28 (diff)
downloadouroboros-1071824054828b9be36f50416f858c49c9acd701.tar.gz
ouroboros-1071824054828b9be36f50416f858c49c9acd701.zip
Merge branch 'be' of bitbucket.org:ouroboros-rina/ouroboros into be
Diffstat (limited to 'src/lib/shm_rdrbuff.c')
-rw-r--r--src/lib/shm_rdrbuff.c804
1 files changed, 804 insertions, 0 deletions
diff --git a/src/lib/shm_rdrbuff.c b/src/lib/shm_rdrbuff.c
new file mode 100644
index 00000000..d42dbea7
--- /dev/null
+++ b/src/lib/shm_rdrbuff.c
@@ -0,0 +1,804 @@
+/*
+ * Ouroboros - Copyright (C) 2016
+ *
+ * Random Deletion Ring Buffer 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_rdrbuff.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_rdrbuff"
+
+#include <ouroboros/logs.h>
+
+#define SHM_BLOCKS_SIZE (SHM_BUFFER_SIZE * SHM_RDRB_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(rdrb) \
+ ((struct shm_du_buff *)(rdrb->shm_base + (*rdrb->ptr_head * \
+ SHM_RDRB_BLOCK_SIZE)))
+
+#define get_tail_ptr(rdrb) \
+ ((struct shm_du_buff *)(rdrb->shm_base + (*rdrb->ptr_tail * \
+ SHM_RDRB_BLOCK_SIZE)))
+
+#define idx_to_du_buff_ptr(rdrb, idx) \
+ ((struct shm_du_buff *)(rdrb->shm_base + (idx * SHM_RDRB_BLOCK_SIZE)))
+
+#define block_ptr_to_idx(rdrb, sdb) \
+ (((uint8_t *)sdb - rdrb->shm_base) / SHM_RDRB_BLOCK_SIZE)
+
+#define shm_rdrb_used(rdrb) \
+ ((*rdrb->ptr_head + SHM_BUFFER_SIZE - *rdrb->ptr_tail) \
+ & (SHM_BUFFER_SIZE - 1))
+#define shm_rdrb_free(rdrb, i) \
+ (shm_rdrb_used(rdrb) + i < SHM_BUFFER_SIZE)
+
+#define shm_rdrb_empty(rdrb) \
+ (*rdrb->ptr_tail == *rdrb->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_rdrbuff {
+ 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 */
+ enum qos_cube qos; /* qos id which this buffer serves */
+ int fd;
+};
+
+static void garbage_collect(struct shm_rdrbuff * rdrb)
+{
+#ifdef SHM_RDRBUFF_MULTI_BLOCK
+ struct shm_du_buff * sdb;
+ while (!shm_rdrb_empty(rdrb) &&
+ (sdb = get_tail_ptr(rdrb))->dst_api == -1)
+ *rdrb->ptr_tail = (*rdrb->ptr_tail + sdb->blocks)
+ & (SHM_BUFFER_SIZE - 1);
+#else
+ while (!shm_rdrb_empty(rdrb) && get_tail_ptr(rdrb)->dst_api == -1)
+ *rdrb->ptr_tail =
+ (*rdrb->ptr_tail + 1) & (SHM_BUFFER_SIZE - 1);
+
+#endif
+}
+
+static void clean_sdus(struct shm_rdrbuff * rdrb, pid_t api)
+{
+ size_t idx = *rdrb->ptr_tail;
+ struct shm_du_buff * buf;
+
+ while (idx != *rdrb->ptr_head) {
+ buf = idx_to_du_buff_ptr(rdrb, idx);
+ if (buf->dst_api == api)
+ buf->dst_api = -1;
+#ifdef SHM_RDRBUFF_MULTI_BLOCK
+ idx = (idx + buf->blocks) & (SHM_BUFFER_SIZE - 1);
+#else
+ idx = (idx + 1) & (SHM_BUFFER_SIZE - 1);
+#endif
+ }
+
+ garbage_collect(rdrb);
+
+ *rdrb->choked = 0;
+}
+
+static char * rdrb_filename(enum qos_cube qos)
+{
+ int chars = 0;
+ char * str;
+ int qm = QOS_MAX;
+
+ do {
+ qm /= 10;
+ ++chars;
+ } while (qm > 0);
+
+ str = malloc(strlen(SHM_RDRB_PREFIX) + chars + 2);
+ if (str == NULL) {
+ LOG_ERR("Failed to create shm_rdrbuff: Out of Memory.");
+ return NULL;
+ }
+
+ sprintf(str, "%s.%d", SHM_RDRB_PREFIX, (int) qos);
+
+ return str;
+}
+
+/* FIXME: create a ringbuffer for each qos cube in the system */
+struct shm_rdrbuff * shm_rdrbuff_create()
+{
+ struct shm_rdrbuff * rdrb;
+ int shm_fd;
+ uint8_t * shm_base;
+ pthread_mutexattr_t mattr;
+ pthread_condattr_t cattr;
+ enum qos_cube qos = QOS_CUBE_BE;
+ char * shm_rdrb_fn = rdrb_filename(qos);
+ if (shm_rdrb_fn == NULL) {
+ LOG_ERR("Could not create rdrbuff. Out of Memory");
+ return NULL;
+ }
+
+ rdrb = malloc(sizeof *rdrb);
+ if (rdrb == NULL) {
+ LOG_DBGF("Could not allocate struct.");
+ return NULL;
+ }
+
+ shm_fd = shm_open(shm_rdrb_fn, O_CREAT | O_EXCL | O_RDWR, 0666);
+ if (shm_fd == -1) {
+ LOG_DBGF("Failed creating shared memory map.");
+ free(shm_rdrb_fn);
+ free(rdrb);
+ return NULL;
+ }
+
+ if (fchmod(shm_fd, 0666)) {
+ LOG_DBGF("Failed to chmod shared memory map.");
+ free(shm_rdrb_fn);
+ free(rdrb);
+ return NULL;
+ }
+
+ if (ftruncate(shm_fd, SHM_FILE_SIZE - 1) < 0) {
+ LOG_DBGF("Failed to extend shared memory map.");
+ free(shm_rdrb_fn);
+ free(rdrb);
+ return NULL;
+ }
+
+ if (write(shm_fd, "", 1) != 1) {
+ LOG_DBGF("Failed to finalise extension of shared memory map.");
+ free(shm_rdrb_fn);
+ free(rdrb);
+ 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_rdrb_fn) == -1)
+ LOG_DBGF("Failed to remove invalid shm.");
+ free(shm_rdrb_fn);
+ free(rdrb);
+ return NULL;
+ }
+
+ rdrb->shm_base = shm_base;
+ rdrb->ptr_head = (size_t *)
+ ((uint8_t *) rdrb->shm_base + SHM_BLOCKS_SIZE);
+ rdrb->ptr_tail = rdrb->ptr_head + 1;
+ rdrb->lock = (pthread_mutex_t *) (rdrb->ptr_tail + 1);
+ rdrb->choked = (size_t *) (rdrb->lock + 1);
+ rdrb->healthy = (pthread_cond_t *) (rdrb->choked + 1);
+ rdrb->full = rdrb->healthy + 1;
+ rdrb->api = (pid_t *) (rdrb->full + 1);
+
+ pthread_mutexattr_init(&mattr);
+ pthread_mutexattr_setpshared(&mattr, PTHREAD_PROCESS_SHARED);
+ pthread_mutexattr_setrobust(&mattr, PTHREAD_MUTEX_ROBUST);
+ pthread_mutex_init(rdrb->lock, &mattr);
+
+ pthread_condattr_init(&cattr);
+ pthread_condattr_setpshared(&cattr, PTHREAD_PROCESS_SHARED);
+ pthread_cond_init(rdrb->full, &cattr);
+ pthread_cond_init(rdrb->healthy, &cattr);
+
+ *rdrb->ptr_head = 0;
+ *rdrb->ptr_tail = 0;
+
+ *rdrb->choked = 0;
+
+ *rdrb->api = getpid();
+
+ rdrb->qos = qos;
+ rdrb->fd = shm_fd;
+
+ free(shm_rdrb_fn);
+
+ return rdrb;
+}
+
+/* FIXME: open a ringbuffer for each qos cube in the system */
+struct shm_rdrbuff * shm_rdrbuff_open()
+{
+ struct shm_rdrbuff * rdrb;
+ int shm_fd;
+ uint8_t * shm_base;
+
+ enum qos_cube qos = QOS_CUBE_BE;
+ char * shm_rdrb_fn = rdrb_filename(qos);
+ if (shm_rdrb_fn == NULL) {
+ LOG_ERR("Could not create rdrbuff. Out of Memory");
+ return NULL;
+ }
+
+ rdrb = malloc(sizeof *rdrb);
+ if (rdrb == NULL) {
+ LOG_DBGF("Could not allocate struct.");
+ return NULL;
+ }
+
+ shm_fd = shm_open(shm_rdrb_fn, O_RDWR, 0666);
+ if (shm_fd < 0) {
+ LOG_DBGF("Failed opening shared memory.");
+ free(shm_rdrb_fn);
+ free(rdrb);
+ 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_DBG("Failed to close invalid shm.");
+ if (shm_unlink(shm_rdrb_fn) == -1)
+ LOG_DBG("Failed to unlink invalid shm.");
+ free(shm_rdrb_fn);
+ free(rdrb);
+ return NULL;
+ }
+
+ rdrb->shm_base = shm_base;
+ rdrb->ptr_head = (size_t *)
+ ((uint8_t *) rdrb->shm_base + SHM_BLOCKS_SIZE);
+ rdrb->ptr_tail = rdrb->ptr_head + 1;
+ rdrb->lock = (pthread_mutex_t *) (rdrb->ptr_tail + 1);
+ rdrb->choked = (size_t *) (rdrb->lock + 1);
+ rdrb->healthy = (pthread_cond_t *) (rdrb->choked + 1);
+ rdrb->full = rdrb->healthy + 1;
+ rdrb->api = (pid_t *) (rdrb->full + 1);
+
+ rdrb->qos = qos;
+ rdrb->fd = shm_fd;
+
+ free(shm_rdrb_fn);
+
+ return rdrb;
+}
+
+void * shm_rdrbuff_sanitize(void * o)
+{
+ struct shm_rdrbuff * rdrb = (struct shm_rdrbuff *) o;
+ struct timespec intv
+ = {SHM_DU_TIMEOUT_MICROS / MILLION,
+ (SHM_DU_TIMEOUT_MICROS % MILLION) * 1000};
+
+ pid_t api;
+
+ if (rdrb == NULL)
+ return (void *) -1;
+
+ if (pthread_mutex_lock(rdrb->lock) == EOWNERDEAD) {
+ LOG_WARN("Recovering dead mutex.");
+ pthread_mutex_consistent(rdrb->lock);
+ }
+
+ pthread_cleanup_push((void (*)(void *)) pthread_mutex_unlock,
+ (void *) rdrb->lock);
+
+ while (true) {
+ int ret = 0;
+ struct timespec now;
+ struct timespec dl;
+
+ if (pthread_cond_wait(rdrb->full, rdrb->lock) == EOWNERDEAD) {
+ LOG_WARN("Recovering dead mutex.");
+ pthread_mutex_consistent(rdrb->lock);
+ }
+
+ *rdrb->choked = 1;
+
+ garbage_collect(rdrb);
+
+ if (shm_rdrb_empty(rdrb))
+ continue;
+
+ api = get_tail_ptr(rdrb)->dst_api;
+
+ if (kill(api, 0)) {
+ LOG_DBGF("Dead process %d left stale sdu.", api);
+ clean_sdus(rdrb, api);
+ continue;
+ }
+
+ clock_gettime(CLOCK_REALTIME, &now);
+ ts_add(&now, &intv, &dl);
+ while (*rdrb->choked) {
+ ret = pthread_cond_timedwait(rdrb->healthy,
+ rdrb->lock,
+ &dl);
+ if (!ret)
+ continue;
+
+ if (ret == EOWNERDEAD) {
+ LOG_WARN("Recovering dead mutex.");
+ pthread_mutex_consistent(rdrb->lock);
+ }
+
+ if (ret == ETIMEDOUT) {
+ LOG_DBGF("SDU timed out (dst: %d).", api);
+ clean_sdus(rdrb, api);
+ }
+ }
+ }
+
+ pthread_cleanup_pop(true);
+
+ return (void *) 0;
+}
+
+void shm_rdrbuff_close(struct shm_rdrbuff * rdrb)
+{
+ if (rdrb == NULL) {
+ LOG_DBGF("Bogus input. Bugging out.");
+ return;
+ }
+
+ if (close(rdrb->fd) < 0)
+ LOG_DBGF("Couldn't close shared memory.");
+
+ if (munmap(rdrb->shm_base, SHM_FILE_SIZE) == -1)
+ LOG_DBGF("Couldn't unmap shared memory.");
+
+ free(rdrb);
+}
+
+void shm_rdrbuff_destroy(struct shm_rdrbuff * rdrb)
+{
+ char * shm_rdrb_fn;
+
+ if (rdrb == NULL) {
+ LOG_DBGF("Bogus input. Bugging out.");
+ return;
+ }
+
+ if (getpid() != *rdrb->api && kill(*rdrb->api, 0) == 0) {
+ LOG_DBG("Process %d tried to destroy active rdrb.", getpid());
+ return;
+ }
+
+ if (close(rdrb->fd) < 0)
+ LOG_DBG("Couldn't close shared memory.");
+
+ if (munmap(rdrb->shm_base, SHM_FILE_SIZE) == -1)
+ LOG_DBG("Couldn't unmap shared memory.");
+
+ shm_rdrb_fn = rdrb_filename(rdrb->qos);
+ if (shm_rdrb_fn == NULL) {
+ LOG_ERR("Could not create rdrbuff. Out of Memory");
+ return;
+ }
+
+ if (shm_unlink(shm_rdrb_fn) == -1)
+ LOG_DBG("Failed to unlink shm.");
+
+ free(rdrb);
+ free(shm_rdrb_fn);
+}
+
+ssize_t shm_rdrbuff_write(struct shm_rdrbuff * rdrb,
+ 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_RDRBUFF_MULTI_BLOCK
+ long blocks = 0;
+ long padblocks = 0;
+#endif
+ int sz = size + sizeof *sdb;
+ uint8_t * write_pos;
+ ssize_t idx = -1;
+
+ if (rdrb == NULL || data == NULL) {
+ LOG_DBGF("Bogus input, bugging out.");
+ return -1;
+ }
+
+#ifndef SHM_RDRBUFF_MULTI_BLOCK
+ if (sz > SHM_RDRB_BLOCK_SIZE) {
+ LOG_DBGF("Multi-block SDU's disabled. Dropping.");
+ return -1;
+ }
+#endif
+ if (pthread_mutex_lock(rdrb->lock) == EOWNERDEAD) {
+ LOG_DBGF("Recovering dead mutex.");
+ pthread_mutex_consistent(rdrb->lock);
+ }
+#ifdef SHM_RDRBUFF_MULTI_BLOCK
+ while (sz > 0) {
+ sz -= SHM_RDRB_BLOCK_SIZE;
+ ++blocks;
+ }
+
+ if (blocks + *rdrb->ptr_head > SHM_BUFFER_SIZE)
+ padblocks = SHM_BUFFER_SIZE - *rdrb->ptr_head;
+
+ if (!shm_rdrb_free(rdrb, (blocks + padblocks))) {
+#else
+ if (!shm_rdrb_free(rdrb, 1)) {
+#endif
+ pthread_cond_signal(rdrb->full);
+ pthread_mutex_unlock(rdrb->lock);
+ return -1;
+ }
+
+#ifdef SHM_RDRBUFF_MULTI_BLOCK
+ if (padblocks) {
+ sdb = get_head_ptr(rdrb);
+ sdb->size = 0;
+ sdb->blocks = padblocks;
+ sdb->dst_api = -1;
+ sdb->du_head = 0;
+ sdb->du_tail = 0;
+
+ *rdrb->ptr_head = 0;
+ }
+#endif
+ sdb = get_head_ptr(rdrb);
+ sdb->size = size;
+ sdb->dst_api = dst_api;
+ sdb->du_head = headspace;
+ sdb->du_tail = sdb->du_head + len;
+#ifdef SHM_RDRBUFF_MULTI_BLOCK
+ sdb->blocks = blocks;
+#endif
+ write_pos = ((uint8_t *) (sdb + 1)) + headspace;
+
+ memcpy(write_pos, data, len);
+
+ idx = *rdrb->ptr_head;
+#ifdef SHM_RDRBUFF_MULTI_BLOCK
+ *rdrb->ptr_head = (*rdrb->ptr_head + blocks) & (SHM_BUFFER_SIZE - 1);
+#else
+ *rdrb->ptr_head = (*rdrb->ptr_head + 1) & (SHM_BUFFER_SIZE - 1);
+#endif
+ pthread_mutex_unlock(rdrb->lock);
+
+ return idx;
+}
+
+ssize_t shm_rdrbuff_write_b(struct shm_rdrbuff * rdrb,
+ 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_RDRBUFF_MULTI_BLOCK
+ long blocks = 0;
+ long padblocks = 0;
+#endif
+ int sz = size + sizeof *sdb;
+ uint8_t * write_pos;
+ ssize_t idx = -1;
+
+ if (rdrb == NULL || data == NULL) {
+ LOG_DBGF("Bogus input, bugging out.");
+ return -1;
+ }
+
+#ifndef SHM_RDRBUFF_MULTI_BLOCK
+ if (sz > SHM_RDRB_BLOCK_SIZE) {
+ LOG_DBGF("Multi-block SDU's disabled. Dropping.");
+ return -1;
+ }
+#endif
+ if (pthread_mutex_lock(rdrb->lock) == EOWNERDEAD) {
+ LOG_DBGF("Recovering dead mutex.");
+ pthread_mutex_consistent(rdrb->lock);
+ }
+
+ pthread_cleanup_push((void(*)(void *))pthread_mutex_unlock,
+ (void *) rdrb->lock);
+
+#ifdef SHM_RDRBUFF_MULTI_BLOCK
+ while (sz > 0) {
+ sz -= SHM_RDRB_BLOCK_SIZE;
+ ++blocks;
+ }
+
+ if (blocks + *rdrb->ptr_head > SHM_BUFFER_SIZE)
+ padblocks = SHM_BUFFER_SIZE - *rdrb->ptr_head;
+
+ while (!shm_rdrb_free(rdrb, (blocks + padblocks))) {
+#else
+ while (!shm_rdrb_free(rdrb, 1)) {
+#endif
+ pthread_cond_signal(rdrb->full);
+ pthread_cond_wait(rdrb->healthy, rdrb->lock);
+ }
+
+#ifdef SHM_RDRBUFF_MULTI_BLOCK
+ if (padblocks) {
+ sdb = get_head_ptr(rdrb);
+ sdb->size = 0;
+ sdb->blocks = padblocks;
+ sdb->dst_api = -1;
+ sdb->du_head = 0;
+ sdb->du_tail = 0;
+
+ *rdrb->ptr_head = 0;
+ }
+#endif
+ sdb = get_head_ptr(rdrb);
+ sdb->size = size;
+ sdb->dst_api = dst_api;
+ sdb->du_head = headspace;
+ sdb->du_tail = sdb->du_head + len;
+#ifdef SHM_RDRBUFF_MULTI_BLOCK
+ sdb->blocks = blocks;
+#endif
+ write_pos = ((uint8_t *) (sdb + 1)) + headspace;
+
+ memcpy(write_pos, data, len);
+
+ idx = *rdrb->ptr_head;
+#ifdef SHM_RDRBUFF_MULTI_BLOCK
+ *rdrb->ptr_head = (*rdrb->ptr_head + blocks) & (SHM_BUFFER_SIZE - 1);
+#else
+ *rdrb->ptr_head = (*rdrb->ptr_head + 1) & (SHM_BUFFER_SIZE - 1);
+#endif
+ pthread_cleanup_pop(true);
+
+ return idx;
+}
+
+int shm_rdrbuff_read(uint8_t ** dst,
+ struct shm_rdrbuff * rdrb,
+ ssize_t idx)
+{
+ size_t len = 0;
+ struct shm_du_buff * sdb;
+
+ if (idx > SHM_BUFFER_SIZE)
+ return -1;
+
+ if (pthread_mutex_lock(rdrb->lock) == EOWNERDEAD) {
+ LOG_DBGF("Recovering dead mutex.");
+ pthread_mutex_consistent(rdrb->lock);
+ }
+
+ if (shm_rdrb_empty(rdrb)) {
+ pthread_mutex_unlock(rdrb->lock);
+ return -1;
+ }
+
+ sdb = idx_to_du_buff_ptr(rdrb, idx);
+ len = sdb->du_tail - sdb->du_head;
+ *dst = ((uint8_t *) (sdb + 1)) + sdb->du_head;
+
+ pthread_mutex_unlock(rdrb->lock);
+
+ return len;
+}
+
+int shm_rdrbuff_remove(struct shm_rdrbuff * rdrb, ssize_t idx)
+{
+ if (idx > SHM_BUFFER_SIZE)
+ return -1;
+
+ if (pthread_mutex_lock(rdrb->lock) == EOWNERDEAD) {
+ LOG_DBGF("Recovering dead mutex.");
+ pthread_mutex_consistent(rdrb->lock);
+ }
+
+ if (shm_rdrb_empty(rdrb)) {
+ pthread_mutex_unlock(rdrb->lock);
+ return -1;
+ }
+
+ idx_to_du_buff_ptr(rdrb, idx)->dst_api = -1;
+
+ if (idx != *rdrb->ptr_tail) {
+ pthread_mutex_unlock(rdrb->lock);
+ return 0;
+ }
+
+ garbage_collect(rdrb);
+
+ *rdrb->choked = 0;
+
+ pthread_cond_broadcast(rdrb->healthy);
+
+ pthread_mutex_unlock(rdrb->lock);
+
+ return 0;
+}
+
+uint8_t * shm_du_buff_head_alloc(struct shm_rdrbuff * rdrb,
+ int idx,
+ ssize_t size)
+{
+ struct shm_du_buff * sdb;
+ uint8_t * buf;
+
+ if (rdrb == NULL)
+ return NULL;
+
+ if (idx < 0 || idx > SHM_BUFFER_SIZE)
+ return NULL;
+
+ if (pthread_mutex_lock(rdrb->lock) == EOWNERDEAD) {
+ LOG_DBGF("Recovering dead mutex.");
+ pthread_mutex_consistent(rdrb->lock);
+ }
+
+ sdb = idx_to_du_buff_ptr(rdrb, idx);
+
+ if ((long) (sdb->du_head - size) < 0) {
+ pthread_mutex_unlock(rdrb->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(rdrb->lock);
+
+ return buf;
+}
+
+uint8_t * shm_du_buff_tail_alloc(struct shm_rdrbuff * rdrb,
+ int idx,
+ ssize_t size)
+{
+ struct shm_du_buff * sdb;
+ uint8_t * buf;
+
+ if (rdrb == NULL)
+ return NULL;
+
+ if (idx < 0 || idx > SHM_BUFFER_SIZE)
+ return NULL;
+
+ if (pthread_mutex_lock(rdrb->lock) == EOWNERDEAD) {
+ LOG_DBGF("Recovering dead mutex.");
+ pthread_mutex_consistent(rdrb->lock);
+ }
+
+ sdb = idx_to_du_buff_ptr(rdrb, idx);
+
+ if (sdb->du_tail + size >= sdb->size) {
+ pthread_mutex_unlock(rdrb->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(rdrb->lock);
+
+ return buf;
+}
+
+int shm_du_buff_head_release(struct shm_rdrbuff * rdrb,
+ int idx,
+ ssize_t size)
+{
+ struct shm_du_buff * sdb;
+
+ if (rdrb == NULL)
+ return -1;
+
+ if (idx < 0 || idx > SHM_BUFFER_SIZE)
+ return -1;
+
+ if (pthread_mutex_lock(rdrb->lock) == EOWNERDEAD) {
+ LOG_DBGF("Recovering dead mutex.");
+ pthread_mutex_consistent(rdrb->lock);
+ }
+
+ sdb = idx_to_du_buff_ptr(rdrb, idx);
+
+ if (size > sdb->du_tail - sdb->du_head) {
+ pthread_mutex_unlock(rdrb->lock);
+ LOG_DBGF("Tried to release beyond sdu boundary.");
+ return -EOVERFLOW;
+ }
+
+ sdb->du_head += size;
+
+ pthread_mutex_unlock(rdrb->lock);
+
+ return 0;
+}
+
+int shm_du_buff_tail_release(struct shm_rdrbuff * rdrb,
+ int idx,
+ ssize_t size)
+{
+ struct shm_du_buff * sdb;
+
+ if (rdrb == NULL)
+ return -1;
+
+ if (idx < 0 || idx > SHM_BUFFER_SIZE)
+ return -1;
+
+ if (pthread_mutex_lock(rdrb->lock) == EOWNERDEAD) {
+ LOG_DBGF("Recovering dead mutex.");
+ pthread_mutex_consistent(rdrb->lock);
+ }
+
+ sdb = idx_to_du_buff_ptr(rdrb, idx);
+
+ if (size > sdb->du_tail - sdb->du_head) {
+ pthread_mutex_unlock(rdrb->lock);
+ LOG_DBGF("Tried to release beyond sdu boundary.");
+ return -EOVERFLOW;
+ }
+
+ sdb->du_tail -= size;
+
+ pthread_mutex_unlock(rdrb->lock);
+
+ return 0;
+}