On Wed, 31 Jul 2024 10:46:08 +0200, Amadeusz Sławiński wrote:
On 6/19/2024 5:28 PM, Takashi Iwai wrote:
For making it easer for applications to create a virtual UMP Endpoint and UMP blocks, add two API helper functions.
snd_seq_create_ump_endpoint() creates (unsurprisingly) a UMP Endpoint, based on the given snd_ump_endpoint_info_t information. The number of (max) UMP groups belonging to this Endpoint has to be specified. This function sets up the Endpoint info on the sequencer client, and creates a MIDI 2.0 UMP port as well as UMP Group ports automatically. The name of the sequencer client is updated from the Endpoint name, too.
After creating a UMP Endpoint, create each UMP Block via snd_seq_create_ump_block() function with a snd_ump_block_info_t info. The associated groups for each block have to be specified there. The port names and capability bits are updated accordingly after setting each block information.
Signed-off-by: Takashi Iwai tiwai@suse.de
...
if (*blknames) {strlcat(blknames, ", ", sizeof(blknames));strlcat(blknames, (const char *)bp->name,sizeof(blknames));FYI, this seems to introduce build problems on systems that do not have strlcpy:
During build: seqmid.c: In function ‘update_group_ports’: seqmid.c:672:33: warning: implicit declaration of function ‘strlcat’; did you mean ‘strncat’? [-Wimplicit-function-declaration] 672 | strlcat(blknames, ", ", sizeof(blknames)); | ^~~~~~~ | strncat
And then during linking: /usr/bin/ld: seq/.libs/libseq.a(seqmid.o): in function `update_group_ports': /home/amade/workdir/avs/alsa-lib/src/seq/seqmid.c:672: undefined reference to `strlcat' /usr/bin/ld: /home/amade/workdir/avs/alsa-lib/src/seq/seqmid.c:673: undefined reference to `strlcat' collect2: error: ld returned 1 exit status
Thanks, I'll modify it to avoid strlcat() like below.
Takashi
-- 8< -- Subject: [PATCH] seq: Avoid strlcat()
strlcat() isn't available in every system, so better to avoid it. Rewrite the code without strlcat().
Fixes: 6167b8ce3e80 ("seq: Add API helper functions for creating UMP Endpoint and Blocks") Link: https://lore.kernel.org/0796c157-1ac3-47a3-9d54-ba86f59d64d5@linux.intel.com Signed-off-by: Takashi Iwai tiwai@suse.de --- src/seq/seqmid.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-)
diff --git a/src/seq/seqmid.c b/src/seq/seqmid.c index 08c62d5c24b8..b30db4075254 100644 --- a/src/seq/seqmid.c +++ b/src/seq/seqmid.c @@ -635,6 +635,7 @@ static void update_group_ports(snd_seq_t *seq, snd_ump_endpoint_info_t *ep) char blknames[64]; char name[64]; unsigned int caps = 0; + int len;
blknames[0] = 0; for (b = 0; b < ep->num_blocks; b++) { @@ -668,14 +669,13 @@ static void update_group_ports(snd_seq_t *seq, snd_ump_endpoint_info_t *ep)
if (!*bp->name) continue; - if (*blknames) { - strlcat(blknames, ", ", sizeof(blknames)); - strlcat(blknames, (const char *)bp->name, - sizeof(blknames)); - } else { + len = strlen(blknames); + if (len) + snprintf(blknames + len, sizeof(blknames) - len, + ", %s", bp->name); + else snd_strlcpy(blknames, (const char *)bp->name, sizeof(blknames)); - } }
if (!*blknames)