When using SCPI over serial (over USB), we want the header without waiting
for the terminating newline, as otherwise the transfer may time out.
sr_scpi_get_data() will block until the message is complete.
g_get_monotonic_time() returns current time in microseconds, use the same
granularity for storing the read timeout.
There is also no need to check the timeout if data has just been read.
When nothing was received in a read attempt, we need not adjust the
buffered data's read position nor the glib string object's size. Skip
any processing for empty input, just keep checking for timeouts.
Routine sr_scpi_get_data() checks for free space in the receive buffer,
and resizes the buffer when free space drops below a threshold. The
previous logic assumed that the resize and the read logic would interact
in some specific way to achieve the desired operation.
Adjust the buffer resize such that more free space is pre-allocated, yet
the payload size of the buffer is not affected. This eliminates the
dependency of the optional resize logic from subsequent activity for
reception of data that is non-optional.
Add comments while we are here, outline the steps taken in the
sr_scpi_get_data() routine.
Undo the change which skips management activities when no data was
received. This change breaks the current implementation, and needs to
get deferred until a delicate interaction between the resize and the
read logic has been eliminated.
Slightly rephrase the SCPI code which parses the responses that carry
(binary) data blocks. Be explicit about NUL termination when parsing the
leading length spec in the response, obsoleting the array initializer.
Add lots of comments and group source code lines to better reflect
what's happening from the protocol's perspective.
Fix the returned error code in the path which reads responses of
excessive length in chunks. The previous implementation detected errors
but always returned code 0 (success).
When nothing was received in a read attempt, we need not adjust the
buffered data's read position nor the glib string object's size. Skip
any processing for empty input, just keep checking for timeouts.
Drop an initial assignment to a variable which never takes effect.
Add braces around the body of a more complex if block. Separate routines
from each other by exactly one empty line.
Binary block data is specified in IEEE 488.2. First character is '#',
followed by a single ascii digit denoting the the number of digits needed
for the length specification. Length is given in bytes.
This allows drivers to replace retrieval of comma separated ASCII values
with binary formats. See bug #791.
While some transports add a terminating (carriagereturn+)linefeed
unconditionally, the USBTMC transport does not. At least the R&S HMO1002
requires the linefeed and locks up otherwise. Fixes bug #784.
This changes the TCP and VXI transport from CR+LF to LF only.
Also fixes a possible memory leak for VXI, where the temporary command
buffer was not freed in case of a write error.
This fixes parts of bug #423.
The list of fixed warnings:
src/output/srzip.c:285:3: warning: Value stored to 'ret' is never read
ret = zip_append(o, logic->data, logic->unitsize, logic->length);
^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
src/scpi/scpi.c:610:2: warning: Value stored to 'ret' is never read
ret = SR_OK;
^ ~~~~~
src/scpi/scpi.c:667:2: warning: Value stored to 'ret' is never read
ret = SR_OK;
^ ~~~~~
src/dmm/vc870.c:410:2: warning: Value stored to 'info_local' is never read
info_local = (struct vc870_info *)info;
^ ~~~~~~~~~~~~~~~~~~~~~~~~~
src/hardware/conrad-digi-35-cpu/api.c:130:2: warning: Value stored to 'ret' is never read
ret = SR_OK;
^ ~~~~~
src/hardware/fx2lafw/api.c:658:2: warning: Value stored to 'timeout' is never read
timeout = fx2lafw_get_timeout(devc);
^ ~~~~~~~~~~~~~~~~~~~~~~~~~
src/hardware/gmc-mh-1x-2x/protocol.c:941:3: warning: Value stored to 'retc' is never read
retc = SR_ERR_ARG;
^ ~~~~~~~~~~
src/hardware/gmc-mh-1x-2x/api.c:168:2: warning: Value stored to 'model' is never read
model = METRAHIT_NONE;
^ ~~~~~~~~~~~~~
src/hardware/ikalogic-scanalogic2/api.c:325:2: warning: Value stored to 'ret' is never read
ret = SR_OK;
^ ~~~~~
src/hardware/openbench-logic-sniffer/api.c:185:3: warning: Value stored to 'devc' is never read
devc = sdi->priv;
^ ~~~~~~~~~
src/hardware/rigol-ds/api.c:813:3: warning: Value stored to 'devc' is never read
devc = sdi->priv;
^ ~~~~~~~~~
src/hardware/scpi-pps/api.c:405:2: warning: Value stored to 'ret' is never read
ret = SR_OK;
^ ~~~~~
src/hardware/yokogawa-dlm/api.c:239:2: warning: Value stored to 'ret' is never read
ret = SR_ERR_NA;
^ ~~~~~~~~~
Since Autoconf places some important feature flags only into the
configuration header, it is necessary to include it globally to
guarantee a consistent build.
A few of these were pretty serious, like missing arguments,
passing integers where a string was expected, and so on.
In some places, change the types used by the code rather than
just the format strings.
Move the include flags for files in the source tree from
configure.ac to Makefile.am where they belong. Also use
AM_CPPFLAGS instead of CFLAGS/CXXFLAGS to make sure the
files in the build/source tree are always picked up first.
Also, remove the include/libsigrok sub-directory from the
search path, thereby making the <libsigrok/> prefix mandatory
when building libsigrok itself. This matches the convention
already imposed on users of the library.
Some devices with more than one microcontroller report the firmware
version for each of them, giving us more than four tokens. When that
happens, sigrok aborts, even though it received a valid response.
This happens, for example with the Chroma 61604:
'Chroma ATE,61604,001060,1.25,1.34,1.20'
On a Hameg HMO1024 you get incomplete data because the USB transfer takes
longer than the scpi->read_timeout_ms of 1 second that is defined in
scpi_dev_inst_new(). Therefore reset the timeout in sr_scpi_get_string()
whenever the device sends a partial response.
Use g_malloc0() for small allocations and assume they always
succeed. Simplify error handling in a few places accordingly.
Don't always sanity-check parameters for non-public (SR_PRIV)
functions, we require the developers to invoke them correctly.
This allows further error handling simplifications.
libgpib is the userspace component to linux-gpib's kernel modules that
implement low-level interface drivers.
When libsigrok gets userspace GPIB interface drivers, that backend will
be the "official" scpi_gpib.
Sven Schnelle
Uwe Hermann
Stefan Brüns
Gerhard Sittig
Martin Ling
Bert Vermeulen
Daniel Elstner
Alexandru Gagniuc
Mathias Katzer
Soeren Apel