From 5f207112974349b289bb84162309faa6177fb98e Mon Sep 17 00:00:00 2001
From: Donough Liu <liudingming@bytedance.com>
Date: Wed, 20 Mar 2024 04:13:33 +0800
Subject: [PATCH] Better error message (#167)

---
 src/avutil/error.rs | 1 +
 src/error.rs        | 4 ++--
 2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/src/avutil/error.rs b/src/avutil/error.rs
index 5aa4d1f..68ac6b7 100644
--- a/src/avutil/error.rs
+++ b/src/avutil/error.rs
@@ -7,6 +7,7 @@ use std::ffi::{c_int, CStr};
 /// Return `Some(description)` on success, a negative value if a description for
 /// errnum cannot be found.
 pub fn err2str(errnum: c_int) -> Option<String> {
+    // mimicks `av_err2str()`
     const ERRBUF_SIZE: usize = AV_ERROR_MAX_STRING_SIZE as usize;
     let mut errbuf = [0u8; ERRBUF_SIZE];
     if unsafe { ffi::av_strerror(errnum, errbuf.as_mut_ptr() as _, ERRBUF_SIZE) } == 0 {
diff --git a/src/error.rs b/src/error.rs
index ed8ea8e..d74c8ff 100644
--- a/src/error.rs
+++ b/src/error.rs
@@ -6,13 +6,13 @@ use std::{
 };
 use thiserror::Error;
 
-use crate::{ffi, shared::AVERROR_EAGAIN};
+use crate::{avutil::err2str, ffi, shared::AVERROR_EAGAIN};
 
 /// All the error variants of rsmpeg.
 #[non_exhaustive]
 #[derive(Error, Debug, Eq, PartialEq)]
 pub enum RsmpegError {
-    #[error("AVERROR({0})")]
+    #[error("AVERROR({0}): `{}`", err2str(*.0).unwrap_or_else(|| "Unknown error code.".to_string()))]
     AVError(c_int),
     #[error("{0}")]
     CustomError(String),