log -L: fix overlapping input ranges

diff --git a/strbuf.c b/strbuf.c
index 9a373bef70b7fdd434c02d1ca753fcc8f799ecc2..48e9abb5c2069bfc02a32747004bf51799dda0f1 100644 (file)
--- a/strbuf.c
+++ b/strbuf.c
@@ -204,6 +204,54 @@ void strbuf_addf(struct strbuf *sb, const char *fmt, ...)
        va_end(ap);
 }
 
+static void add_lines(struct strbuf *out,
+                       const char *prefix1,
+                       const char *prefix2,
+                       const char *buf, size_t size)
+{
+       while (size) {
+               const char *prefix;
+               const char *next = memchr(buf, '\n', size);
+               next = next ? (next + 1) : (buf + size);
+
+               prefix = (prefix2 && buf[0] == '\n') ? prefix2 : prefix1;
+               strbuf_addstr(out, prefix);
+               strbuf_add(out, buf, next - buf);
+               size -= next - buf;
+               buf = next;
+       }
+       strbuf_complete_line(out);
+}
+
+void strbuf_add_commented_lines(struct strbuf *out, const char *buf, size_t size)
+{
+       static char prefix1[3];
+       static char prefix2[2];
+
+       if (prefix1[0] != comment_line_char) {
+               sprintf(prefix1, "%c ", comment_line_char);
+               sprintf(prefix2, "%c", comment_line_char);
+       }
+       add_lines(out, prefix1, prefix2, buf, size);
+}
+
+void strbuf_commented_addf(struct strbuf *sb, const char *fmt, ...)
+{
+       va_list params;
+       struct strbuf buf = STRBUF_INIT;
+       int incomplete_line = sb->len && sb->buf[sb->len - 1] != '\n';
+
+       va_start(params, fmt);
+       strbuf_vaddf(&buf, fmt, params);
+       va_end(params);
+
+       strbuf_add_commented_lines(sb, buf.buf, buf.len);
+       if (incomplete_line)
+               sb->buf[--sb->len] = '\0';
+
+       strbuf_release(&buf);
+}
+
 void strbuf_vaddf(struct strbuf *sb, const char *fmt, va_list ap)
 {
        int len;
@@ -414,15 +462,7 @@ int strbuf_read_file(struct strbuf *sb, const char *path, size_t hint)
 void strbuf_add_lines(struct strbuf *out, const char *prefix,
                      const char *buf, size_t size)
 {
-       while (size) {
-               const char *next = memchr(buf, '\n', size);
-               next = next ? (next + 1) : (buf + size);
-               strbuf_addstr(out, prefix);
-               strbuf_add(out, buf, next - buf);
-               size -= next - buf;
-               buf = next;
-       }
-       strbuf_complete_line(out);
+       add_lines(out, prefix, NULL, buf, size);
 }
 
 void strbuf_addstr_xml_quoted(struct strbuf *buf, const char *s)