[FFmpeg-devel] [PATCH 2/7] avcodec/golomb: Make emitting error message in get_ue_golomb optional

[Andreas Rheinhardt]

This is designed for scenarios where the caller already checks that the
returned value is within a certain allowed range and returns an error
message if not.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt at gmail.com>
---
 libavcodec/golomb.h | 32 ++++++++++++++++++++++++--------
 1 file changed, 24 insertions(+), 8 deletions(-)

diff --git a/libavcodec/golomb.h b/libavcodec/golomb.h
index 5bfcfe085f..63069f63e5 100644
--- a/libavcodec/golomb.h
+++ b/libavcodec/golomb.h
@@ -47,12 +47,7 @@ extern const uint8_t ff_interleaved_ue_golomb_vlc_code[256];
 extern const  int8_t ff_interleaved_se_golomb_vlc_code[256];
 extern const uint8_t ff_interleaved_dirac_golomb_vlc_code[256];
 
-/**
- * Read an unsigned Exp-Golomb code in the range 0 to 8190.
- *
- * @returns the read value or a negative error code.
- */
-static inline int get_ue_golomb(GetBitContext *gb)
+static inline int get_ue_golomb_internal(GetBitContext *gb, int emit_error_msg)
 {
     unsigned int buf;
 
@@ -67,7 +62,8 @@ static inline int get_ue_golomb(GetBitContext *gb)
     } else {
         int log = 2 * av_log2(buf) - 31;
         if (log < 0) {
-            av_log(NULL, AV_LOG_ERROR, "Invalid UE golomb code\n");
+            if (emit_error_msg)
+                av_log(NULL, AV_LOG_ERROR, "Invalid UE golomb code\n");
             return AVERROR_INVALIDDATA;
         }
         buf >>= log;
@@ -92,7 +88,8 @@ static inline int get_ue_golomb(GetBitContext *gb)
         LAST_SKIP_BITS(re, gb, 32 - log);
         CLOSE_READER(re, gb);
         if (log < 7) {
-            av_log(NULL, AV_LOG_ERROR, "Invalid UE golomb code\n");
+            if (emit_error_msg)
+                av_log(NULL, AV_LOG_ERROR, "Invalid UE golomb code\n");
             return AVERROR_INVALIDDATA;
         }
         buf >>= log;
@@ -103,6 +100,25 @@ static inline int get_ue_golomb(GetBitContext *gb)
 #endif
 }
 
+/**
+ * Read an unsigned Exp-Golomb code in the range 0 to 8190.
+ *
+ * @returns the read value or a negative error code.
+ */
+static inline int get_ue_golomb(GetBitContext *gb)
+{
+    return get_ue_golomb_internal(gb, 1);
+}
+
+/**
+ * Variant of get_ue_golomb that does not emit an error message
+ * if the number is outside the permissible range.
+ */
+static inline int get_ue_golomb2(GetBitContext *gb)
+{
+    return get_ue_golomb_internal(gb, 0);
+}
+
 /**
  * Read an unsigned Exp-Golomb code in the range 0 to UINT32_MAX-1.
  */
-- 
2.20.1