From f88ec3114dfdb5f284367d7602a06dc021409616 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Petr=20P=C3=ADsa=C5=99?= <ppisar@redhat.com>
Date: Fri, 26 Jan 2024 10:36:07 +0100
Subject: [PATCH] Fix formatting a trailing backslash and a percent sign
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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 2f2b702..2184e4e 100644
--- a/src/time.c
+++ b/src/time.c
@@ -585,12 +585,13 @@ summarize (fp, fmt, command, resp)
 	      break;
 	    case '\0':
 	      putc ('?', fp);
-	      return;
+	      break;
 	    default:
 	      putc ('?', fp);
 	      putc (*fmt, fp);
 	    }
-	  ++fmt;
+	  if (*fmt != '\0')
+	    ++fmt;
 	  break;
 
 	case '\\':		/* Format escape.  */
@@ -605,12 +606,17 @@ 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