avformat/internal: Add ff_get_frame_filename

It's similar to av_get_frame_filename2 but with int64_t number
support. Make av_get_frame_filename* a wrapper over
ff_get_frame_filename.

Co-authored-by: Filip Mašić <shoutplenty@gmail.com>
Signed-off-by: Zhao Zhili <zhilizhao@tencent.com>

libavformat/internal.h

@@ -745,6 +745,22 @@ void ff_format_set_url(AVFormatContext *s, char *url);
  */
 int ff_match_url_ext(const char *url, const char *extensions);
 
+/**
+ * Return in 'buf' the path with '%d' replaced by a number.
+ *
+ * Also handles the '%0nd' format where 'n' is the total number
+ * of digits and '%%'.
+ *
+ * @param buf destination buffer
+ * @param buf_size destination buffer size
+ * @param path path with substitution template
+ * @param number the number to substitute
+ * @param flags AV_FRAME_FILENAME_FLAGS_*
+ * @return 0 if OK, -1 on format error
+ */
+int ff_get_frame_filename(char *buf, int buf_size, const char *path,
+                          int64_t number, int flags);
+
 struct FFOutputFormat;
 struct FFInputFormat;
 void avpriv_register_devices(const struct FFOutputFormat * const o[],

libavformat/utils.c

@@ -280,7 +280,7 @@ uint64_t ff_parse_ntp_time(uint64_t ntp_ts)
     return (sec * 1000000) + usec;
 }
 
-int av_get_frame_filename2(char *buf, int buf_size, const char *path, int number, int flags)
+int ff_get_frame_filename(char *buf, int buf_size, const char *path, int64_t number, int flags)
 {
     const char *p;
     char *q, buf1[20], c;
@@ -313,7 +313,7 @@ int av_get_frame_filename2(char *buf, int buf_size, const char *path, int number
                 percentd_found = 1;
                 if (number < 0)
                     nd += 1;
-                snprintf(buf1, sizeof(buf1), "%0*d", nd, number);
+                snprintf(buf1, sizeof(buf1), "%0*" PRId64, nd, number);
                 len = strlen(buf1);
                 if ((q - buf + len) > buf_size - 1)
                     goto fail;
@@ -338,9 +338,14 @@ fail:
     return -1;
 }
 
+int av_get_frame_filename2(char *buf, int buf_size, const char *path, int number, int flags)
+{
+    return ff_get_frame_filename(buf, buf_size, path, number, flags);
+}
+
 int av_get_frame_filename(char *buf, int buf_size, const char *path, int number)
 {
-    return av_get_frame_filename2(buf, buf_size, path, number, 0);
+    return ff_get_frame_filename(buf, buf_size, path, number, 0);
 }
 
 void av_url_split(char *proto, int proto_size,