Package: speechd-up
Version: 0.5~20110719-9
SYMPTOMS
I ran into a failed assertion. When pressing certain Unicode
characters like U+20AC (EURO SIGN) or U+2192 (RIGHTWARDS ARROW) on the
console via a keyboard, speechd-up exits suddenly. The same happens
when moving the cursor over a Unicode character in a text editor or on
a readline prompt. I first ran into this under Buster.
DIAGNOSIS
>From strace:
...
write(2, "speechd-up: speechd-up.c:457: parse_buf: Assertion `bytes <=
BUF_SIZE' failed.\n", 79) = 79
...
WORKAROUND
The problem only manifests when speechd-up is started with the default
command line "speechd-up -l1". Putting this into
/etc/default/speechd-up prevents the bug from being triggered:
DAEMON_OPTS="$DAEMON_OPTS -D/dev/softsynthu -cUTF-8"
ANALYSIS
The error is in speechd-up.c:main():
750 ...
751 chars_read = read(fd, buf, BUF_SIZE);
752 if (chars_read < 0) {
753 ...
chars_read is declared as size_t, but read() returns ssize_t, thus a
failed read returning -1 (errno==11/EAGAIN in my case) triggers the
assertion in parse_buf().
The patch fixes the error and also adds code to retry the read after a
short delay.
--- speechd-up-0.5~20110719/speechd-up.c 2020-09-02 21:05:47.357273940 +0200
+++ speechd-up-0.5~20110719/speechd-up.c 2020-09-02 21:07:45.929271575 +0200
@@ -631,6 +631,7 @@
int main(int argc, char *argv[])
{
size_t chars_read;
+ ssize_t chars_read_signed;
char buf[BUF_SIZE + 1];
int ret;
@@ -748,11 +749,20 @@
close(fd);
return -1;
}
- chars_read = read(fd, buf, BUF_SIZE);
- if (chars_read < 0) {
- FATAL(5, "read() failed");
- close(fd);
- return -1;
+ chars_read_signed = read(fd, buf, BUF_SIZE);
+ if (chars_read_signed < 0) {
+ if (errno == EAGAIN) {
+ LOG(5, "read() failed with EAGAIN, retrying");
+ usleep(1000);
+ continue;
+ } else {
+ FATAL(5, "read() failed with %d,%s",
+ errno, strerror(errno));
+ close(fd);
+ return -1;
+ }
+ } else {
+ chars_read = chars_read_signed;
}
buf[chars_read] = 0;
LOG(5, "Main loop characters read = %d : (%s)", chars_read,
