pcm: avoid calling pcm_hw->close() twice
It would result in a double free:
$ tinyplay example.wav
failed to open for pcm 0,0
*** glibc detected *** ./utils/tinyplay: double free or corruption (fasttop): 0x402dc258 ***
Aborted
$
The crash happens here:
Program received signal SIGABRT, Aborted.
0x40070e78 in raise () from /lib/libc.so.6
Missing separate debuginfos, use: debuginfo-install glibc-2.16-34.olpc.0.fc18.armv7hl libgcc-4.7.2-8.fc18.armv7hl
(gdb) bt
#0 0x40070e78 in raise () from /lib/libc.so.6
#1 0x400724b8 in abort () from /lib/libc.so.6
#2 0x400ad6e0 in ?? () from /lib/libc.so.6
#3 0x400b54e8 in ?? () from /lib/libc.so.6
#4 0x2a00486c in pcm_hw_close ()
#5 0x2a0032e0 in pcm_close ()
#6 0x2a0016b0 in ctx_init ()
#7 0x2a000c98 in main ()
(gdb)
The previous free was done here:
Breakpoint 1, 0x400b8b8c in free () from /lib/libc.so.6
(gdb) bt
#0 0x400b8b8c in free () from /lib/libc.so.6
#1 0x2a00486c in pcm_hw_close ()
#2 0x2a003674 in pcm_open ()
#3 0x2a0015e8 in ctx_init ()
#4 0x2a000c98 in main ()
(gdb)
diff --git a/src/pcm.c b/src/pcm.c
index c28e098..c3807a7 100644
--- a/src/pcm.c
+++ b/src/pcm.c
@@ -898,7 +898,7 @@
if (!pcm->snd_node || pcm_type != SND_NODE_TYPE_PLUGIN) {
oops(pcm, -ENODEV, "no device (hw/plugin) for card(%u), device(%u)",
card, device);
- return pcm;
+ goto fail_close;
}
pcm->ops = &plug_ops;
pcm->fd = pcm->ops->open(card, device, flags, &pcm->data, pcm->snd_node);
@@ -907,7 +907,7 @@
if (pcm->fd < 0) {
oops(pcm, errno, "cannot open device (%u) for card (%u)",
device, card);
- return pcm;
+ goto fail_close;
}
pcm->flags = flags;
@@ -954,9 +954,8 @@
if (pcm->snd_node)
snd_utils_close_dev_node(pcm->snd_node);
#endif
- pcm->ops->close(pcm->data);
- pcm->fd = -1;
- return pcm;
+ pcm_close(pcm);
+ return &bad_pcm;
}
/** Checks if a PCM file has been opened without error.