PATCH: Make ztrftime pass more things to strftime

[Mikael Magnusson <mikachu@xxxxxxxxx>]

I poked at this for an hour, and this is the first version that passes
make check and doesn't segfault randomly, so it is not very well tested,
to say the least. Opinions on the approach?

---
 Src/utils.c | 21 +++++++++++++++++++--
 1 file changed, 19 insertions(+), 2 deletions(-)

diff --git a/Src/utils.c b/Src/utils.c
index aea89c3..0e079c9 100644
--- a/Src/utils.c
+++ b/Src/utils.c
@@ -2887,7 +2887,7 @@ ztrftime(char *buf, int bufsize, char *fmt, struct tm *tm, long usec)
     int hr12;
 #ifdef HAVE_STRFTIME
     int decr;
-    char tmp[4];
+    char *fmtstart;
 #else
     static char *astr[] =
     {"Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"};
@@ -2903,7 +2903,11 @@ ztrftime(char *buf, int bufsize, char *fmt, struct tm *tm, long usec)
 	    int strip;
 	    int digs = 3;
 
+#ifdef HAVE_STRFTIME
+	    fmtstart =
+#endif
 	    fmt++;
+
 	    if (*fmt == '-') {
 		strip = 1;
 		fmt++;
@@ -2928,6 +2932,7 @@ ztrftime(char *buf, int bufsize, char *fmt, struct tm *tm, long usec)
 	     */
 	    if (ztrftimebuf(&bufsize, 2))
 		return -1;
+morefmt:
 	    switch (*fmt++) {
 	    case '.':
 		if (ztrftimebuf(&bufsize, digs))
@@ -3052,13 +3057,24 @@ ztrftime(char *buf, int bufsize, char *fmt, struct tm *tm, long usec)
 		if (fmt[-1] != '%')
 		    *buf++ = fmt[-1];
 #else
+	    case 'E':
+	    case 'O':
+	    case '^':
+	    case '#':
+	    case '_':
+	    case '0' ... '9':
+		goto morefmt;
 	    default:
 		/*
 		 * Remember we've already allowed for two characters
 		 * in the accounting in bufsize (but nowhere else).
 		 */
+		{
+		int size = fmt - fmtstart;
+		char *tmp = zhalloc(size + 1);
+		strncpy(tmp, fmtstart, size);
+		tmp[size] = '\0';
 		*buf = '\1';
-		sprintf(tmp, strip ? "%%-%c" : "%%%c", fmt[-1]);
 		if (!strftime(buf, bufsize + 2, tmp, tm))
 		{
 		    if (*buf) {
@@ -3070,6 +3086,7 @@ ztrftime(char *buf, int bufsize, char *fmt, struct tm *tm, long usec)
 		decr = strlen(buf);
 		buf += decr;
 		bufsize -= decr - 2;
+		}
 #endif
 		break;
 	    }
-- 
2.4.0