diff options
Diffstat (limited to 'strbuf.c')
| -rw-r--r-- | strbuf.c | 33 |
1 files changed, 33 insertions, 0 deletions
@@ -710,3 +710,36 @@ char *xstrfmt(const char *fmt, ...) return ret; } + +void strbuf_addftime(struct strbuf *sb, const char *fmt, const struct tm *tm) +{ + size_t hint = 128; + size_t len; + + if (!*fmt) + return; + + strbuf_grow(sb, hint); + len = strftime(sb->buf + sb->len, sb->alloc - sb->len, fmt, tm); + + if (!len) { + /* + * strftime reports "0" if it could not fit the result in the buffer. + * Unfortunately, it also reports "0" if the requested time string + * takes 0 bytes. So our strategy is to munge the format so that the + * output contains at least one character, and then drop the extra + * character before returning. + */ + struct strbuf munged_fmt = STRBUF_INIT; + strbuf_addf(&munged_fmt, "%s ", fmt); + while (!len) { + hint *= 2; + strbuf_grow(sb, hint); + len = strftime(sb->buf + sb->len, sb->alloc - sb->len, + munged_fmt.buf, tm); + } + strbuf_release(&munged_fmt); + len--; /* drop munged space */ + } + strbuf_setlen(sb, sb->len + len); +} |