1 files changed, 99 insertions, 0 deletions
diff --git a/strbuf.c b/strbuf.c
index c606f339d6..9583875621 100644
--- a/strbuf.c
+++ b/strbuf.c
@@ -710,3 +710,102 @@ 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);
+}
+
+/*
+ * Returns the length of a line, without trailing spaces.
+ *
+ * If the line ends with newline, it will be removed too.
+ */
+static size_t cleanup(char *line, size_t len)
+{
+	while (len) {
+		unsigned char c = line[len - 1];
+		if (!isspace(c))
+			break;
+		len--;
+	}
+
+	return len;
+}
+
+/*
+ * Remove empty lines from the beginning and end
+ * and also trailing spaces from every line.
+ *
+ * Turn multiple consecutive empty lines between paragraphs
+ * into just one empty line.
+ *
+ * If the input has only empty lines and spaces,
+ * no output will be produced.
+ *
+ * If last line does not have a newline at the end, one is added.
+ *
+ * Enable skip_comments to skip every line starting with comment
+ * character.
+ */
+void strbuf_stripspace(struct strbuf *sb, int skip_comments)
+{
+	int empties = 0;
+	size_t i, j, len, newlen;
+	char *eol;
+
+	/* We may have to add a newline. */
+	strbuf_grow(sb, 1);
+
+	for (i = j = 0; i < sb->len; i += len, j += newlen) {
+		eol = memchr(sb->buf + i, '\n', sb->len - i);
+		len = eol ? eol - (sb->buf + i) + 1 : sb->len - i;
+
+		if (skip_comments && len && sb->buf[i] == comment_line_char) {
+			newlen = 0;
+			continue;
+		}
+		newlen = cleanup(sb->buf + i, len);
+
+		/* Not just an empty line? */
+		if (newlen) {
+			if (empties > 0 && j > 0)
+				sb->buf[j++] = '\n';
+			empties = 0;
+			memmove(sb->buf + j, sb->buf + i, newlen);
+			sb->buf[newlen + j++] = '\n';
+		} else {
+			empties++;
+		}
+	}
+
+	strbuf_setlen(sb, j);
+}