utf8: refactor `strbuf_utf8_replace` to not rely on preallocated buffer

[thirdparty/git.git] / utf8.c

diff --git a/utf8.c b/utf8.c
index 077daf4b20a76aef57b95767f1e8d77746fe71da..d8a16af87c969712aca773839e6686c43f0db0ba 100644 (file)
--- a/utf8.c
+++ b/utf8.c
@@ -365,26 +365,20 @@ void strbuf_add_wrapped_bytes(struct strbuf *buf, const char *data, int len,
 void strbuf_utf8_replace(struct strbuf *sb_src, int pos, int width,
                         const char *subst)
 {
-       struct strbuf sb_dst = STRBUF_INIT;
-       char *src = sb_src->buf;
-       char *end = src + sb_src->len;
-       char *dst;
-       int w = 0, subst_len = 0;
+       const char *src = sb_src->buf, *end = sb_src->buf + sb_src->len;
+       struct strbuf dst;
+       int w = 0;
 
-       if (subst)
-               subst_len = strlen(subst);
-       strbuf_grow(&sb_dst, sb_src->len + subst_len);
-       dst = sb_dst.buf;
+       strbuf_init(&dst, sb_src->len);
 
        while (src < end) {
+               const char *old;
                int glyph_width;
-               char *old;
                size_t n;
 
                while ((n = display_mode_esc_sequence_len(src))) {
-                       memcpy(dst, src, n);
+                       strbuf_add(&dst, src, n);
                        src += n;
-                       dst += n;
                }
 
                if (src >= end)
@@ -404,21 +398,19 @@ void strbuf_utf8_replace(struct strbuf *sb_src, int pos, int width,
 
                if (glyph_width && w >= pos && w < pos + width) {
                        if (subst) {
-                               memcpy(dst, subst, subst_len);
-                               dst += subst_len;
+                               strbuf_addstr(&dst, subst);
                                subst = NULL;
                        }
-                       w += glyph_width;
-                       continue;
+               } else {
+                       strbuf_add(&dst, old, src - old);
                }
-               memcpy(dst, old, src - old);
-               dst += src - old;
+
                w += glyph_width;
        }
-       strbuf_setlen(&sb_dst, dst - sb_dst.buf);
-       strbuf_swap(sb_src, &sb_dst);
+
+       strbuf_swap(sb_src, &dst);
 out:
-       strbuf_release(&sb_dst);
+       strbuf_release(&dst);
 }
 
 /*