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diff --git a/share/examples/sound/mmap.c b/share/examples/sound/mmap.c
new file mode 100644
--- /dev/null
+++ b/share/examples/sound/mmap.c
@@ -0,0 +1,217 @@
+/*
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
+ * Copyright (c) 2026 Goran Mekić
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <time.h>
+
+#include "oss.h"
+
+static int64_t
+gettime_ns(void)
+{
+ struct timespec ts;
+
+ if (clock_gettime(CLOCK_MONOTONIC, &ts) != 0)
+ err(1, "clock_gettime failed");
+ return ((int64_t)ts.tv_sec * 1000000000LL + ts.tv_nsec);
+}
+
+static void
+sleep_until_ns(int64_t target_ns)
+{
+ struct timespec ts;
+
+ ts.tv_sec = target_ns / 1000000000LL;
+ ts.tv_nsec = target_ns % 1000000000LL;
+ if (clock_nanosleep(CLOCK_MONOTONIC, TIMER_ABSTIME, &ts, NULL) != 0)
+ err(1, "clock_nanosleep failed");
+}
+
+static unsigned
+frame_stepping(unsigned sample_rate)
+{
+ return (16U * (1U + (sample_rate / 50000U)));
+}
+
+static int64_t
+update_map_progress(int fd, unsigned long request, int *map_pointer,
+ int64_t *map_progress, int buffer_bytes, int frag_size, int frame_size)
+{
+ count_info info = {};
+ unsigned delta, max_bytes, cycles;
+ int fragments;
+
+ if (ioctl(fd, request, &info) < 0)
+ err(1, "Failed to get mmap pointer");
+ if (info.ptr < 0 || info.ptr >= buffer_bytes)
+ errx(1, "Pointer out of bounds: %d", info.ptr);
+ if ((info.ptr % frame_size) != 0)
+ errx(1, "Pointer %d not aligned to frame size %d", info.ptr,
+ frame_size);
+ if (info.blocks < 0)
+ errx(1, "Invalid block count %d", info.blocks);
+
+ delta = (info.ptr + buffer_bytes - *map_pointer) % buffer_bytes;
+ max_bytes = (info.blocks + 1) * frag_size - 1;
+ if (max_bytes >= delta) {
+ cycles = max_bytes - delta;
+ cycles -= cycles % buffer_bytes;
+ delta += cycles;
+ }
+ fragments = delta / frag_size;
+ if (info.blocks < fragments || info.blocks > fragments + 1)
+ warnx("Pointer block mismatch: ptr=%d blocks=%d delta=%u",
+ info.ptr, info.blocks, delta);
+
+ *map_pointer = info.ptr;
+ *map_progress += delta;
+ return (*map_progress);
+}
+
+static void
+copy_ring(void *dstv, const void *srcv, int buffer_bytes, int offset,
+ int length)
+{
+ uint8_t *dst = dstv;
+ const uint8_t *src = srcv;
+ int first;
+
+ if (length <= 0)
+ return;
+ first = buffer_bytes - offset;
+ if (first > length)
+ first = length;
+ memcpy(dst + offset, src + offset, first);
+ if (first < length)
+ memcpy(dst, src, length - first);
+}
+
+int
+main(int argc, char *argv[])
+{
+ int ch, bytes;
+ int frag_size, frame_size, verbose = 0;
+ int map_pointer = 0;
+ unsigned step_frames;
+ int64_t frame_ns, start_ns, next_wakeup_ns;
+ int64_t read_progress = 0, write_progress = 0;
+ oss_syncgroup sync_group = { 0, 0, { 0 } };
+ struct config config_in = {
+ .device = "/dev/dsp",
+ .mode = O_RDONLY | O_EXCL | O_NONBLOCK,
+ .format = AFMT_S32_NE,
+ .sample_rate = 48000,
+ .mmap = 1,
+ };
+ struct config config_out = {
+ .device = "/dev/dsp",
+ .mode = O_WRONLY | O_EXCL | O_NONBLOCK,
+ .format = AFMT_S32_NE,
+ .sample_rate = 48000,
+ .mmap = 1,
+ };
+
+ while ((ch = getopt(argc, argv, "v")) != -1) {
+ switch (ch) {
+ case 'v':
+ verbose = 1;
+ break;
+ }
+ }
+ argc -= optind;
+ argv += optind;
+
+ if (!verbose)
+ printf("Use -v for verbose mode\n");
+ oss_init(&config_in);
+ oss_init(&config_out);
+ if (config_in.buffer_info.bytes != config_out.buffer_info.bytes)
+ errx(1,
+ "Input and output configurations have different buffer sizes");
+ bytes = config_in.buffer_info.bytes;
+ frag_size = config_in.buffer_info.fragsize;
+ frame_size = config_in.sample_size * config_in.audio_info.max_channels;
+ step_frames = frame_stepping(config_in.sample_rate);
+ frame_ns = 1000000000LL / config_in.sample_rate;
+ if (config_in.audio_info.max_channels !=
+ config_out.audio_info.max_channels)
+ errx(1,
+ "Input and output configurations have different number of channels");
+ if (frag_size != config_out.buffer_info.fragsize)
+ errx(1,
+ "Input and output configurations have different fragment sizes");
+ memset(config_out.buf, 0, bytes);
+
+ /* Configure and start sync group */
+ sync_group.mode = PCM_ENABLE_INPUT;
+ if (ioctl(config_in.fd, SNDCTL_DSP_SYNCGROUP, &sync_group) < 0)
+ err(1, "Failed to add input to syncgroup");
+ sync_group.mode = PCM_ENABLE_OUTPUT;
+ if (ioctl(config_out.fd, SNDCTL_DSP_SYNCGROUP, &sync_group) < 0)
+ err(1, "Failed to add output to syncgroup");
+ if (ioctl(config_in.fd, SNDCTL_DSP_SYNCSTART, &sync_group.id) < 0)
+ err(1, "Starting sync group failed");
+
+ start_ns = gettime_ns();
+ read_progress = update_map_progress(config_in.fd, SNDCTL_DSP_GETIPTR,
+ &map_pointer, &read_progress, bytes, frag_size, frame_size);
+ write_progress = read_progress;
+ next_wakeup_ns = start_ns;
+
+ /* Main loop */
+ for (;;) {
+ sleep_until_ns(next_wakeup_ns);
+ read_progress = update_map_progress(config_in.fd,
+ SNDCTL_DSP_GETIPTR, &map_pointer, &read_progress, bytes,
+ frag_size, frame_size);
+ if (read_progress > write_progress) {
+ int offset = write_progress % bytes;
+ int length = read_progress - write_progress;
+
+ copy_ring(config_out.buf, config_in.buf, bytes, offset,
+ length);
+ write_progress = read_progress;
+ if (verbose)
+ printf("copied %d bytes at %d (abs %lld)\n",
+ length, offset, (long long)write_progress);
+ }
+ next_wakeup_ns += (int64_t)step_frames * frame_ns;
+ if (next_wakeup_ns < gettime_ns())
+ next_wakeup_ns = gettime_ns();
+ }
+
+ /* Cleanup */
+ if (munmap(config_in.buf, bytes) != 0)
+ err(1, "Memory unmap failed");
+ config_in.buf = NULL;
+ if (munmap(config_out.buf, bytes) != 0)
+ err(1, "Memory unmap failed");
+ config_out.buf = NULL;
+ close(config_in.fd);
+ close(config_out.fd);
+
+ return (0);
+}

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