Re: [PATCH] perf tools: Fix error handling of lzma decompression

[Arnaldo Carvalho de Melo]

Em Sun, Aug 21, 2016 at 03:57:33PM +0800, Shawn Lin escreveu:
> lzma_decompress_to_file never actually close the file
> pointer, let's fix it.
> 
> Signed-off-by: Shawn Lin <shawn.lin@xxxxxxxxxxxxxx>

Thanks, I changed the logic a bit to shorten the patch, this is how it
ended up:


commit ffe67c2fabf128122b30fbf0ac498928e171b0b3
Author: Shawn Lin <shawn.lin@xxxxxxxxxxxxxx>
Date:   Sun Aug 21 15:57:33 2016 +0800

    perf tools: Fix error handling of lzma decompression
    
    lzma_decompress_to_file() never actually closes the file pointer, let's
    fix it.
    
    Signed-off-by: Shawn Lin <shawn.lin@xxxxxxxxxxxxxx>
    Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
    Link: http://lkml.kernel.org/r/1471766253-1964-1-git-send-email-shawn.lin@xxxxxxxxxxxxxx
    [ Make err = -1, the common case, set it to 0 before the error label ]
    Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>

diff --git a/tools/perf/util/lzma.c b/tools/perf/util/lzma.c
index 95a1acb61245..9ddea5cecd94 100644
--- a/tools/perf/util/lzma.c
+++ b/tools/perf/util/lzma.c
@@ -29,6 +29,7 @@ int lzma_decompress_to_file(const char *input, int output_fd)
 	lzma_action action = LZMA_RUN;
 	lzma_stream strm   = LZMA_STREAM_INIT;
 	lzma_ret ret;
+	int err = -1;
 
 	u8 buf_in[BUFSIZE];
 	u8 buf_out[BUFSIZE];
@@ -45,7 +46,7 @@ int lzma_decompress_to_file(const char *input, int output_fd)
 	if (ret != LZMA_OK) {
 		pr_err("lzma: lzma_stream_decoder failed %s (%d)\n",
 			lzma_strerror(ret), ret);
-		return -1;
+		goto err_fclose;
 	}
 
 	strm.next_in   = NULL;
@@ -60,7 +61,7 @@ int lzma_decompress_to_file(const char *input, int output_fd)
 
 			if (ferror(infile)) {
 				pr_err("lzma: read error: %s\n", strerror(errno));
-				return -1;
+				goto err_fclose;
 			}
 
 			if (feof(infile))
@@ -74,7 +75,7 @@ int lzma_decompress_to_file(const char *input, int output_fd)
 
 			if (writen(output_fd, buf_out, write_size) != write_size) {
 				pr_err("lzma: write error: %s\n", strerror(errno));
-				return -1;
+				goto err_fclose;
 			}
 
 			strm.next_out  = buf_out;
@@ -83,13 +84,15 @@ int lzma_decompress_to_file(const char *input, int output_fd)
 
 		if (ret != LZMA_OK) {
 			if (ret == LZMA_STREAM_END)
-				return 0;
+				break;
 
 			pr_err("lzma: failed %s\n", lzma_strerror(ret));
-			return -1;
+			goto err_fclose;
 		}
 	}
 
+	err = 0;
+err_fclose:
 	fclose(infile);
-	return 0;
+	return err;
 }

> 
>  tools/perf/util/lzma.c | 19 ++++++++++++-------
>  1 file changed, 12 insertions(+), 7 deletions(-)
> 
> diff --git a/tools/perf/util/lzma.c b/tools/perf/util/lzma.c
> index 95a1acb..a95d473 100644
> --- a/tools/perf/util/lzma.c
> +++ b/tools/perf/util/lzma.c
> @@ -29,6 +29,7 @@ int lzma_decompress_to_file(const char *input, int output_fd)
>  	lzma_action action = LZMA_RUN;
>  	lzma_stream strm   = LZMA_STREAM_INIT;
>  	lzma_ret ret;
> +	int err = 0;
>  
>  	u8 buf_in[BUFSIZE];
>  	u8 buf_out[BUFSIZE];
> @@ -45,7 +46,8 @@ int lzma_decompress_to_file(const char *input, int output_fd)
>  	if (ret != LZMA_OK) {
>  		pr_err("lzma: lzma_stream_decoder failed %s (%d)\n",
>  			lzma_strerror(ret), ret);
> -		return -1;
> +		err = -1;
> +		goto err_fclose;
>  	}
>  
>  	strm.next_in   = NULL;
> @@ -60,7 +62,8 @@ int lzma_decompress_to_file(const char *input, int output_fd)
>  
>  			if (ferror(infile)) {
>  				pr_err("lzma: read error: %s\n", strerror(errno));
> -				return -1;
> +				err = -1;
> +				goto err_fclose;
>  			}
>  
>  			if (feof(infile))
> @@ -74,7 +77,8 @@ int lzma_decompress_to_file(const char *input, int output_fd)
>  
>  			if (writen(output_fd, buf_out, write_size) != write_size) {
>  				pr_err("lzma: write error: %s\n", strerror(errno));
> -				return -1;
> +				err = -1;
> +				goto err_fclose;
>  			}
>  
>  			strm.next_out  = buf_out;
> @@ -83,13 +87,14 @@ int lzma_decompress_to_file(const char *input, int output_fd)
>  
>  		if (ret != LZMA_OK) {
>  			if (ret == LZMA_STREAM_END)
> -				return 0;
> +				goto err_fclose;
>  
>  			pr_err("lzma: failed %s\n", lzma_strerror(ret));
> -			return -1;
> +			err = -1;
> +			goto err_fclose;
>  		}
>  	}
> -
> +err_fclose:
>  	fclose(infile);
> -	return 0;
> +	return err;
>  }
> -- 
> 2.3.7
>