support multiline data output from scripts run under the grapher

This is accompanied by support for multiline output in hover text.

* grapher/StapParser.cxx (ioCallback): Read data 'til the end of line
  character, not just '\n'. Be careful to use I/O functions that don't
  treat '\n' specially.
* grapher/StapParser.hxx: ditto
* grapher/CairoWidget.cxx (CairoTextBox::draw): Perform line breaks
  for hover text.
* testsuite/systemtap.examples/general/grapher.stp: Do multiline
  output of keyboard events. Also, fix longstanding breaking in the
  pty probe.

1 files changed, 13 insertions, 5 deletions

diff --git a/testsuite/systemtap.examples/general/grapher.stp b/testsuite/systemtap.examples/general/grapher.stp
index e8655b37..c1c60437 100755
--- a/testsuite/systemtap.examples/general/grapher.stp
+++ b/testsuite/systemtap.examples/general/grapher.stp
@@ -8,7 +8,7 @@ printf ("%%DataSet:pty 50 0000ff discreet\n");
 printf ("cpu %%Title:CPU utilization\n");
 printf ("cpu %%XAxisTitle:Time\n");
 printf ("cpu %%YAxisTitle:Percent\n");
-
+printf ("%%LineEnd:0\n");
 }
 
 # CPU utilization
@@ -26,17 +26,25 @@ function qsq_util_reset(q) {
 
 probe timer.ms(100) {  # collect utilization percentages frequently
   foreach (q in qnames)
-    printf("cpu %d %d\n", gettimeofday_ms(), qsq_util_reset(q))
+    printf("cpu %d %d%c", gettimeofday_ms(), qsq_util_reset(q), 0)
 }
 
 probe kernel.function("kbd_event") {
  if ($event_type == 1 && $value)
-   printf("kbd %d %d\n", gettimeofday_ms(), $event_code)
+   printf("kbd %d %d\n0x%x%c", gettimeofday_ms(), $event_code, $event_code, 0)
 }
 
 probe kernel.function("pty_write") {
- if (count > 0)
-  printf("pty %d %.5s\n", gettimeofday_ms(), buf)
+    if ($count > 0) {
+            printf("pty %d ", gettimeofday_ms())
+            str = kernel_string($buf)
+            for (i = 0; i < $count; ++i) {
+                # yes it's gross
+                c = substr(str, i, 1)
+                printf("%s\n", text_str(c))
+            }
+            printf("%c", 0)
+    }
 }