[alsa-devel] [PATCH] aplay: Adjust buffer sizes to fix snprintf warnings

[Rosen Penev]

It also reduces compiled size slightly.

aplay.c: In function 'capture':
aplay.c:3055:34: error: '-01' directive output may be truncated writing 3
bytes into a region of size between 1 and 4097 [-Werror=format-truncation=
]
 3055 |    snprintf(namebuf, namelen, "%s-01", buf);
      |                                  ^~~
aplay.c:3055:4: note: 'snprintf' output between 4 and 4100 bytes into a
destination of size 4097
 3055 |    snprintf(namebuf, namelen, "%s-01", buf);
      |    ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
aplay.c:3053:34: error: '-01.' directive output may be truncated writing 4
bytes into a region of size between 1 and 4097 [-Werror=format-truncation=
]
 3053 |    snprintf(namebuf, namelen, "%s-01.%s", buf, s);
      |                                  ^~~~
aplay.c:3053:4: note: 'snprintf' output 5 or more bytes (assuming 4101)
into a destination of size 4097
 3053 |    snprintf(namebuf, namelen, "%s-01.%s", buf, s);
      |    ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
aplay.c:3065:34: error: '%02i' directive output may be truncated writing
between 2 and 10 bytes into a region of size between 0 and 4096 [-Werror=
format-truncation=]
 3065 |   snprintf(namebuf, namelen, "%s-%02i", buf, filecount);
      |                                  ^~~~
aplay.c:3065:30: note: directive argument in the range [1, 2147483647]
 3065 |   snprintf(namebuf, namelen, "%s-%02i", buf, filecount);
      |                              ^~~~~~~~~
aplay.c:3065:3: note: 'snprintf' output between 4 and 4108 bytes into a
destination of size 4097
 3065 |   snprintf(namebuf, namelen, "%s-%02i", buf, filecount);
      |   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
aplay.c:3063:34: error: '%02i' directive output may be truncated writing
between 2 and 10 bytes into a region of size between 0 and 4096 [-Werror=
format-truncation=]
 3063 |   snprintf(namebuf, namelen, "%s-%02i.%s", buf, filecount, s);
      |                                  ^~~~
aplay.c:3063:30: note: directive argument in the range [1, 2147483647]
 3063 |   snprintf(namebuf, namelen, "%s-%02i.%s", buf, filecount, s);
      |                              ^~~~~~~~~~~~
aplay.c:3063:3: note: 'snprintf' output 5 or more bytes (assuming 4109)
into a destination of size 4097
 3063 |   snprintf(namebuf, namelen, "%s-%02i.%s", buf, filecount, s);

Signed-off-by: Rosen Penev <rosenp at gmail.com>
---
 aplay/aplay.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/aplay/aplay.c b/aplay/aplay.c
index 9c5a11b..1a887e4 100644
--- a/aplay/aplay.c
+++ b/aplay/aplay.c
@@ -3017,7 +3017,7 @@ static int new_capture_file(char *name, char *namebuf, size_t namelen,
 			    int filecount)
 {
 	char *s;
-	char buf[PATH_MAX+1];
+	char buf[PATH_MAX-10];
 	time_t t;
 	struct tm *tmp;
 
@@ -3124,7 +3124,7 @@ static void capture(char *orig_name)
 	int tostdout=0;		/* boolean which describes output stream */
 	int filecount=0;	/* number of files written */
 	char *name = orig_name;	/* current filename */
-	char namebuf[PATH_MAX+1];
+	char namebuf[PATH_MAX+2];
 	off64_t count, rest;		/* number of bytes to capture */
 	struct stat statbuf;
 
-- 
2.23.0