utf8: add function to align a string into given strbuf

Add strbuf_utf8_align() which will align a given string into a strbuf
as per given align_type and width. If the width is greater than the
string length then no alignment is performed.

Helped-by: Eric Sunshine <sunshine@sunshineco.com>
Mentored-by: Christian Couder <christian.couder@gmail.com>
Mentored-by: Matthieu Moy <matthieu.moy@grenoble-inp.fr>
Signed-off-by: Karthik Nayak <karthik.188@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/utf8.c b/utf8.c
index 28e6d76a425db4c16a8cc32e6f17c7aa72c2b1f0..00e10c86ad7ea7bcc2d53a90a2f608dd66d47462 100644 (file)
--- a/utf8.c
+++ b/utf8.c
@@ -644,3 +644,24 @@ int skip_utf8_bom(char **text, size_t len)
        *text += strlen(utf8_bom);
        return 1;
 }
+
+void strbuf_utf8_align(struct strbuf *buf, align_type position, unsigned int width,
+                      const char *s)
+{
+       int slen = strlen(s);
+       int display_len = utf8_strnwidth(s, slen, 0);
+       int utf8_compensation = slen - display_len;
+
+       if (display_len >= width) {
+               strbuf_addstr(buf, s);
+               return;
+       }
+
+       if (position == ALIGN_LEFT)
+               strbuf_addf(buf, "%-*s", width + utf8_compensation, s);
+       else if (position == ALIGN_MIDDLE) {
+               int left = (width - display_len) / 2;
+               strbuf_addf(buf, "%*s%-*s", left, "", width - left + utf8_compensation, s);
+       } else if (position == ALIGN_RIGHT)
+               strbuf_addf(buf, "%*s", width + utf8_compensation, s);
+}

diff --git a/utf8.h b/utf8.h
index 5a9e94bee62fd2ed62dcbc82aee12bfc6d75e254..7930b44f19c701cc671d9639289782abb1812034 100644 (file)
--- a/utf8.h
+++ b/utf8.h
@@ -55,4 +55,19 @@ int mbs_chrlen(const char **text, size_t *remainder_p, const char *encoding);
  */
 int is_hfs_dotgit(const char *path);
 
+typedef enum {
+       ALIGN_LEFT,
+       ALIGN_MIDDLE,
+       ALIGN_RIGHT
+} align_type;
+
+/*
+ * Align the string given and store it into a strbuf as per the
+ * 'position' and 'width'. If the given string length is larger than
+ * 'width' than then the input string is not truncated and no
+ * alignment is done.
+ */
+void strbuf_utf8_align(struct strbuf *buf, align_type position, unsigned int width,
+                      const char *s);
+
 #endif