It's possible for the HARDWARE\DEVICEMAP\SERIALCOMM key to not exist in
the registry if there are no serial ports at all and never have been, as
discovered on my rather minimalist gaming machine.
Handle that case gracefully and return an empty list.
RegOpenKeyEx() and RegQueryInfoKey() return system error codes directly,
not by setting the thread-local errno equivalent that is returned by
GetLastError().
When returning SP_ERR_FAIL, our API specifies that sp_last_error_code()
may be called immediately afterwards to get the system error code. In
this case that would not work, as it would call GetLastError() and miss
the directly-returned result.
We therefore need to call SetLastError() with the error code before
returning with SP_ERR_FAIL.
In platforms 21 and higher of the NDK, linux/serial.h is available,
which it was not before. This broke the build, because the configure
script would detect the availability of 'struct serial_struct' in that
header and set HAVE_STRUCT_SERIAL_STRUCT, but the #ifndef __ANDROID__
in libserialport_internal.h stopped us actually including the header.
This change fixes things to build with all versions of the NDK, and is
tested with builds for arm from versions 9 to 24.
Version 21 also added availability of tcdrain(), so we also use that
where available, and only use the direct ioctl() method on NDK < 21.
Fixes#1078.
serialport.c: In function 'get_time':
serialport.c:64:6: warning: implicit declaration of function 'clock_gettime' [-Wimplicit-function-declaration]
if (clock_gettime(CLOCK_MONOTONIC, &ts) == -1)
^
serialport.c:64:20: error: 'CLOCK_MONOTONIC' undeclared (first use in this function)
if (clock_gettime(CLOCK_MONOTONIC, &ts) == -1)
^
serialport.c:64:20: note: each undeclared identifier is reported only once for each function it appears in
serialport.c:65:17: error: 'CLOCK_REALTIME' undeclared (first use in this function)
clock_gettime(CLOCK_REALTIME, &ts);
^
serialport.c: At top level:
serialport.c:60:13: warning: 'get_time' defined but not used [-Wunused-function]
static void get_time(struct timeval *time)
^
In wc_to_utf8() in windows.c, the zero terminator is written to an invalid
array index, which results in 2 bytes being zeroed in a random place in the
stack. This sometimes causes a crash when running sp_list_ports() (depending
on string length and compiler optimisation settings).
sizeof(wc_str) returns the size in bytes, so cannot be used directly as an
index into that array, it should be divided by sizeof(WCHAR). Otherwise the
zero terminator index is approximately twice what it should be.
This fixes bug #1031.
readir() is threadsafe on both linux and freebsd anyway.
The rationale behind the readdir_r() deprecation is in the glibc manual:
https://www.gnu.org/software/libc/manual/html_node/Reading_002fClosing-Directory.html
This fixes the following warning with recent glibc:
linux.c: In function ‘list_ports’:
linux.c:197:2: warning: ‘readdir_r’ is deprecated [-Wdeprecated-declarations]
while (!readdir_r(dir, &entry, &result) && result) {
^~~~~
