From 2e2ed39dac9578862fb37d74e44cf4cf92c9b4bd Mon Sep 17 00:00:00 2001 From: Andreas Rheinhardt Date: Wed, 10 Mar 2021 02:34:14 +0100 Subject: dnn/dnn_backend_native: Avoid allocation for checking file magic Reviewed-by: Guo, Yejun Signed-off-by: Andreas Rheinhardt --- libavfilter/dnn/dnn_backend_native.c | 22 ++++++---------------- 1 file changed, 6 insertions(+), 16 deletions(-) (limited to 'libavfilter/dnn') diff --git a/libavfilter/dnn/dnn_backend_native.c b/libavfilter/dnn/dnn_backend_native.c index 3bc253c1ad..93fa6c6bcf 100644 --- a/libavfilter/dnn/dnn_backend_native.c +++ b/libavfilter/dnn/dnn_backend_native.c @@ -114,10 +114,10 @@ static DNNReturnType get_output_native(void *model, const char *input_name, int // For DEPTH_TO_SPACE layer: block_size DNNModel *ff_dnn_load_model_native(const char *model_filename, DNNFunctionType func_type, const char *options, AVFilterContext *filter_ctx) { +#define DNN_NATIVE_MAGIC "FFMPEGDNNNATIVE" DNNModel *model = NULL; - char header_expected[] = "FFMPEGDNNNATIVE"; - char *buf; - size_t size; + // sizeof - 1 to skip the terminating '\0' which is not written in the file + char buf[sizeof(DNN_NATIVE_MAGIC) - 1]; int version, header_size, major_version_expected = 1; NativeModel *native_model = NULL; AVIOContext *model_file_context; @@ -138,20 +138,10 @@ DNNModel *ff_dnn_load_model_native(const char *model_filename, DNNFunctionType f /** * check file header with string and version */ - size = sizeof(header_expected); - buf = av_malloc(size); - if (!buf) { + if (avio_read(model_file_context, buf, sizeof(buf)) != sizeof(buf) || + memcmp(buf, DNN_NATIVE_MAGIC, sizeof(buf))) goto fail; - } - - // size - 1 to skip the ending '\0' which is not saved in file - avio_get_str(model_file_context, size - 1, buf, size); - dnn_size = size - 1; - if (strncmp(buf, header_expected, size) != 0) { - av_freep(&buf); - goto fail; - } - av_freep(&buf); + dnn_size = sizeof(buf); version = (int32_t)avio_rl32(model_file_context); dnn_size += 4; -- cgit v1.2.3