run-in-simulavr.sh: implement G-code sending handshaking.

Now it waits for an "ok" before sending the next line, like all
the G-code sending hosts do. This allows sending arbitrarily long
G-codes. The 60 seconds simulated time limit is still in place to
avoid endless simulations.

The standard performance simulation now runs more G-code and
results in slightly different numbers accordingly:

cd testcases
./run-in-simulavr.sh short-moves.gcode smooth-curves.gcode triangle-odd.gcode

    FLASH  : 20540 bytes         144%        67%        33%      16%
    RAM    :  2188 bytes         214%       107%        54%      27%
    EEPROM :    32 bytes           4%         2%         2%       1%

short-moves.gcode statistics:
LED on occurences: 888.
LED on time minimum: 304 clock cycles.
LED on time maximum: 720 clock cycles.
LED on time average: 313.256 clock cycles.

smooth-curves.gcode statistics:
LED on occurences: 36511.
LED on time minimum: 304 clock cycles.
LED on time maximum: 706 clock cycles.
LED on time average: 349.172 clock cycles.

triangle-odd.gcode statistics:
LED on occurences: 1636.
LED on time minimum: 304 clock cycles.
LED on time maximum: 710 clock cycles.
LED on time average: 332.32 clock cycles.

testcases/run-in-simulavr.sh

@@ -20,10 +20,16 @@ fi
 
 
 # General preparation.
+PIPE_IN_FILE=$(mktemp -u)
+PIPE_OUT_FILE=$(mktemp -u)
 TRACEIN_FILE=$(mktemp)
 STATISTICS_FILE=$(mktemp)
 
-trap 'cat '${STATISTICS_FILE}'; rm -f '${TRACEIN_FILE}' '${STATISTICS_FILE} 0
+trap 'cat '${STATISTICS_FILE}'; rm -f '${PIPE_IN_FILE}' '${PIPE_OUT_FILE}' \
+     '${TRACEIN_FILE}' '${STATISTICS_FILE} 0
+
+mkfifo ${PIPE_IN_FILE} || exit 1
+mkfifo ${PIPE_OUT_FILE} || exit 1
 
 
 # Prepare statistics.
@@ -82,21 +88,36 @@ for GCODE_FILE in $*; do
   VEL_FILE="${FILE}.processed.vcd"
 
 
-  # We assume here queue and rx buffer are large enough to read
-  # the file in one chunk. If not, raise MOVEBUFFER_SIZE in config.h.
+  # Start the simulator and send the file line by line.
+  exec 3<>${PIPE_IN_FILE}
+  exec 4<>${PIPE_OUT_FILE}
+
   "${SIMULAVR}" -c vcd:${TRACEIN_FILE}:"${VCD_FILE}" \
                 -f ../build/teacup.elf \
-                -m 60000000000 -v < "${GCODE_FILE}" | \
-    while read -r LINE; do
+                -m 60000000000 -v <&3 >&4 2>&4 &
+
+  while read -rs -u 4 LINE; do
     echo "${LINE}"
     case "${LINE}" in
-        stop)
-          echo "Got \"stop\", killing $(basename ${SIMULAVR})."
+      *"Ran too long"*)
+        echo ">> SimulAVR ended."
+        break
+        ;;
+      "ok"*)
+        read LINE
+        echo ">> Sending ${LINE}"
+        echo "${LINE}" >&3
+        ;;
+      "stop")
+        echo ">> Got \"stop\", killing SimulAVR."
         killall -INT $(basename "${SIMULAVR}") 2> /dev/null || \
           killall -INT "lt-"$(basename "${SIMULAVR}")
         ;;
     esac
-    done 
+  done < "${GCODE_FILE}"
+
+  exec 3>&-
+  exec 4>&-
 
 
   # Make plottable files from VCD files.