Make builtin-rerere use of strbuf nicer and more efficient.

memory is now reused across hunks.

Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/builtin-rerere.c b/builtin-rerere.c
index 58288f61a3861df757f8299e168e847943915e6b..d331772e100d87592d091aa5ad9c38d36bea86c2 100644 (file)
--- a/builtin-rerere.c
+++ b/builtin-rerere.c
@@ -72,13 +72,9 @@ static int handle_file(const char *path,
        SHA_CTX ctx;
        char buf[1024];
        int hunk = 0, hunk_no = 0;
-       struct strbuf minus, plus;
-       struct strbuf *one = &minus, *two = +
+       struct strbuf one, two;
        FILE *f = fopen(path, "r");
-       FILE *out;
-
-       strbuf_init(&minus, 0);
-       strbuf_init(&plus,  0);
+       FILE *out = NULL;
 
        if (!f)
                return error("Could not open %s", path);
@@ -89,51 +85,48 @@ static int handle_file(const char *path,
                        fclose(f);
                        return error("Could not write %s", output);
                }
-       } else
-               out = NULL;
+       }
 
        if (sha1)
                SHA1_Init(&ctx);
 
+       strbuf_init(&one, 0);
+       strbuf_init(&two,  0);
        while (fgets(buf, sizeof(buf), f)) {
                if (!prefixcmp(buf, "<<<<<<< "))
                        hunk = 1;
                else if (!prefixcmp(buf, "======="))
                        hunk = 2;
                else if (!prefixcmp(buf, ">>>>>>> ")) {
-                       int one_is_longer = (one->len > two->len);
-                       int common_len = one_is_longer ? two->len : one->len;
-                       int cmp = memcmp(one->buf, two->buf, common_len);
+                       int cmp = strbuf_cmp(&one, &two);
 
                        hunk_no++;
                        hunk = 0;
-                       if ((cmp > 0) || ((cmp == 0) && one_is_longer)) {
-                               struct strbuf *swap = one;
-                               one = two;
-                               two = swap;
+                       if (cmp > 0) {
+                               strbuf_swap(&one, &two);
                        }
                        if (out) {
                                fputs("<<<<<<<\n", out);
-                               fwrite(one->buf, one->len, 1, out);
+                               fwrite(one.buf, one.len, 1, out);
                                fputs("=======\n", out);
-                               fwrite(two->buf, two->len, 1, out);
+                               fwrite(two.buf, two.len, 1, out);
                                fputs(">>>>>>>\n", out);
                        }
                        if (sha1) {
-                               SHA1_Update(&ctx, one->buf, one->len);
-                               SHA1_Update(&ctx, "\0", 1);
-                               SHA1_Update(&ctx, two->buf, two->len);
-                               SHA1_Update(&ctx, "\0", 1);
+                               SHA1_Update(&ctx, one.buf, one.len + 1);
+                               SHA1_Update(&ctx, two.buf, two.len + 1);
                        }
-                       strbuf_release(one);
-                       strbuf_release(two);
+                       strbuf_reset(&one);
+                       strbuf_reset(&two);
                } else if (hunk == 1)
-                       strbuf_addstr(one, buf);
+                       strbuf_addstr(&one, buf);
                else if (hunk == 2)
-                       strbuf_addstr(two, buf);
+                       strbuf_addstr(&two, buf);
                else if (out)
                        fputs(buf, out);
        }
+       strbuf_release(&one);
+       strbuf_release(&two);
 
        fclose(f);
        if (out)