Commit 6f5c50fe7c for ffmpeg

commit 6f5c50fe7c0052b26852c012510d1b7d69f1c0a9
Author: Romain Beauxis <romain.beauxis@gmail.com>
Date:   Sun Sep 27 23:28:04 2026 -0500

    libavformat/tests: add ogg_pages

    Print the header fields of every page of an Ogg file, checking each
    page's checksum, so that tests can show the page structure a muxer
    writes.

diff --git a/libavformat/Makefile b/libavformat/Makefile
index 60b0e7f033..437c3edb5a 100644
--- a/libavformat/Makefile
+++ b/libavformat/Makefile
@@ -799,6 +799,7 @@ TESTPROGS-$(CONFIG_HTTP_PROTOCOL)        += http
 TESTPROGS-$(CONFIG_NETWORK)              += noproxy
 TESTPROGS-$(CONFIG_SRTP)                 += srtp
 TESTPROGS-$(CONFIG_IMF_DEMUXER)          += imf
+TESTPROGS-$(CONFIG_OGG_MUXER)            += ogg_pages

 TOOLS     = aviocat                                                     \
             ismindex                                                    \
diff --git a/libavformat/tests/.gitignore b/libavformat/tests/.gitignore
index 2be3cc8fac..f7f9a868c7 100644
--- a/libavformat/tests/.gitignore
+++ b/libavformat/tests/.gitignore
@@ -10,3 +10,4 @@
 /url
 /seek_utils
 /http
+/ogg_pages
diff --git a/libavformat/tests/ogg_pages.c b/libavformat/tests/ogg_pages.c
new file mode 100644
index 0000000000..4c6c18942f
--- /dev/null
+++ b/libavformat/tests/ogg_pages.c
@@ -0,0 +1,95 @@
+/*
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg 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.
+ *
+ * FFmpeg 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 FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <inttypes.h>
+#include <stdio.h>
+#include <string.h>
+
+#include "libavutil/crc.h"
+#include "libavutil/intreadwrite.h"
+
+#define OGG_PAGE_HEADER_SIZE 27
+#define OGG_PAGE_MAX_SIZE    (OGG_PAGE_HEADER_SIZE + 255 + 255 * 255)
+
+static uint8_t page[OGG_PAGE_MAX_SIZE];
+
+int main(int argc, char **argv)
+{
+    const AVCRC *crc_table = av_crc_get_table(AV_CRC_32_IEEE);
+    size_t nb_read;
+    long pos = 0;
+    int ret = 1;
+    FILE *file;
+
+    if (argc != 2) {
+        fprintf(stderr, "Usage: %s <file.ogg>\n"
+                "Print the header of every page and check its checksum.\n",
+                argv[0]);
+        return 1;
+    }
+
+    file = fopen(argv[1], "rb");
+    if (!file) {
+        perror(argv[1]);
+        return 1;
+    }
+
+    while ((nb_read = fread(page, 1, OGG_PAGE_HEADER_SIZE, file)) == OGG_PAGE_HEADER_SIZE) {
+        int nb_segments = page[26], body_size = 0, page_size;
+        uint32_t crc;
+
+        if (memcmp(page, "OggS", 4) ||
+            fread(page + OGG_PAGE_HEADER_SIZE, 1, nb_segments, file) != nb_segments) {
+            fprintf(stderr, "Invalid page at %ld\n", pos);
+            goto end;
+        }
+
+        for (int i = 0; i < nb_segments; i++)
+            body_size += page[OGG_PAGE_HEADER_SIZE + i];
+
+        page_size = OGG_PAGE_HEADER_SIZE + nb_segments + body_size;
+        if (fread(page + page_size - body_size, 1, body_size, file) != body_size) {
+            fprintf(stderr, "Truncated page at %ld\n", pos);
+            goto end;
+        }
+
+        crc = AV_RB32(page + 22);
+        AV_WB32(page + 22, 0);
+        if (av_crc(crc_table, 0, page, page_size) != crc) {
+            fprintf(stderr, "Checksum mismatch in page at %ld\n", pos);
+            goto end;
+        }
+
+        printf("pos=%ld serial=%"PRIu32" sequence=%"PRIu32" granule=%"PRId64
+               " flags=%c%c%c segments=%d size=%d\n",
+               pos, AV_RL32(page + 14), AV_RL32(page + 18),
+               (int64_t)AV_RL64(page + 6),
+               page[5] & 1 ? 'c' : '-', page[5] & 2 ? 'b' : '-',
+               page[5] & 4 ? 'e' : '-', nb_segments, body_size);
+
+        pos += page_size;
+    }
+
+    ret = nb_read || ferror(file);
+    if (ret)
+        fprintf(stderr, "Truncated page at %ld\n", pos);
+
+end:
+    fclose(file);
+    return ret;
+}