From fb9187129c3d07ac6d0f7deaa27f1248394d8f91 Mon Sep 17 00:00:00 2001 From: Andreas Weis Date: Wed, 27 Apr 2016 08:15:17 +0200 Subject: avutil/log: added av_log_format_line2 which returns buffer length The new function behaves the same as av_log_format_line, but also forwards the return value from the underlying snprintf call. This will allow callers to accurately determine the size requirements for the line buffer. Signed-off-by: Andreas Weis Signed-off-by: Michael Niedermayer --- libavutil/log.h | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) (limited to 'libavutil/log.h') diff --git a/libavutil/log.h b/libavutil/log.h index 321748cd80..9b1d66f521 100644 --- a/libavutil/log.h +++ b/libavutil/log.h @@ -317,6 +317,23 @@ AVClassCategory av_default_get_category(void *ptr); void av_log_format_line(void *ptr, int level, const char *fmt, va_list vl, char *line, int line_size, int *print_prefix); +/** + * Format a line of log the same way as the default callback. + * @param line buffer to receive the formatted line; + * may be NULL if line_size is 0 + * @param line_size size of the buffer; at most line_size-1 characters will + * be written to the buffer, plus one null terminator + * @param print_prefix used to store whether the prefix must be printed; + * must point to a persistent integer initially set to 1 + * @return Returns a negative value if an error occured, otherwise returns + * the number of characters that would have been written for a + * sufficiently large buffer, not including the terminating null + * character. If the return value is not less than line_size, it means + * that the log message was truncated to fit the buffer. + */ +int av_log_format_line2(void *ptr, int level, const char *fmt, va_list vl, + char *line, int line_size, int *print_prefix); + #if FF_API_DLOG /** * av_dlog macros -- cgit v1.2.3