From d848bcac4b1160f9e05a9acf5d00d0418285eec3 Mon Sep 17 00:00:00 2001
From: FRIGN <dev@frign.de>
Date: Sun, 21 Jun 2015 15:52:21 +0200
Subject: [PATCH] Fix parameter-usage in printf(1)

1) Don't default to a space for numeric conversions. Instead,
   set flag to 0 and work with it on a case-basis.
   This fixes the wrong output of "printf %d 20" which had a
   space prepended to it (" 20").
2) Add precision for doiuxX, which is zero-padding.
   This fixes the wrong output of "printf %.5d 20" to properly
   print "00020".

Thanks to emg for reporting these!
---
 printf.c | 23 +++++++++++++----------
 1 file changed, 13 insertions(+), 10 deletions(-)

diff --git a/printf.c b/printf.c
index 1335906..d5d852d 100644
--- a/printf.c
+++ b/printf.c
@@ -49,8 +49,8 @@ main(int argc, char *argv[])
 		}
 
 		/* flag */
-		for (flag = ' ', i++; strchr("#-+ 0", format[i]); i++) {
-			flag = format[i];
+		for (flag = '\0', i++; strchr("#-+ 0", format[i]); i++) {
+			if (!flag) flag = format[i];
 		}
 
 		/* field width */
@@ -135,18 +135,21 @@ main(int argc, char *argv[])
 				rarg = ereallocarray(NULL, utflen(arg) + 1, sizeof(*rarg));
 				utftorunestr(arg, rarg);
 				num = rarg[0];
-			} else
+			} else {
 				num = (strlen(arg) > 0) ? estrtonum(arg, LLONG_MIN, LLONG_MAX) : 0;
-			fmt = estrdup("%#*ll#");
-			fmt[1] = flag;
-			fmt[5] = format[i];
-			printf(fmt, width, num);
+			}
+			fmt = estrdup(flag ? "%#*.*ll#" : "%*.*ll#");
+			if (flag)
+				fmt[1] = flag;
+			fmt[flag ? 7 : 6] = format[i];
+			printf(fmt, width, precision, num);
 			free(fmt);
 			break;
 		case 'a': case 'A': case 'e': case 'E': case 'f': case 'F': case 'g': case 'G':
-			fmt = estrdup("%#*.*#");
-			fmt[1] = flag;
-			fmt[5] = format[i];
+			fmt = estrdup(flag ? "%#*.*#" : "%*.*#");
+			if (flag)
+				fmt[1] = flag;
+			fmt[flag ? 5 : 4] = format[i];
 			dou = (strlen(arg) > 0) ? estrtod(arg) : 0;
 			printf(fmt, width, precision, dou);
 			free(fmt);