[PATCH] Fix formatting a trailing backslash and a percent sign

[Petr Písař]

There was a bug report that a trailing backslash leads to printing
a nul byte and an commandline:

$ /usr/bin/time -f 'abc\' sleep 1 2>&1 | hexdump -vC
00000000  61 62 63 3f 5c 00 73 6c  65 65 70 0a              |abc?\.sleep.|
0000000c

This patch fixes it.

A similar fix was already in place for a trailing percent sign, but it
was missing printing an implicit newline as mandated by
the documentation. This patch fixes it either.

Signed-off-by: Petr Písař <ppisar@redhat.com>
---
 src/time.c | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/src/time.c b/src/time.c
index 7b401bc..0d35f82 100644
--- a/src/time.c
+++ b/src/time.c
@@ -658,14 +658,15 @@ summarize (fp, fmt, command, resp)
 
             case '\0':
               putc ('?', fp);
-              return;
+              break;
 
             default:
               putc ('?', fp);
               putc (*fmt, fp);
             }
 
-          ++fmt;
+          if (*fmt != '\0')
+            ++fmt;
           break; /* end of "case '%'" */
 
         case '\\':             /* Format escape.  */
@@ -680,12 +681,17 @@ summarize (fp, fmt, command, resp)
             case '\\':
               putc ('\\', fp);
               break;
+            case '\0':
+              putc ('?', fp);
+              putc ('\\', fp);
+              break;
             default:
               putc ('?', fp);
               putc ('\\', fp);
               putc (*fmt, fp);
             }
-          ++fmt;
+          if (*fmt != '\0')
+            ++fmt;
           break;
 
         default:
-- 
2.43.0