bp = find_beginning_of_line(buf, scanp);
- if (*bp != '\n') {
- strbuf_splice(&sb, 0, 0, buf, endp - buf);
- if (pos)
- break; /* need to fill another block */
- scanp = buf - 1; /* leave loop */
- } else {
+ if (*bp == '\n') {
/*
- * (bp + 1) thru endp is the beginning of the
- * current line we have in sb
+ * The newline is the end of the previous line,
+ * so we know we have complete line starting
+ * at (bp + 1). Prefix it onto any prior data
+ * we collected for the line and process it.
*/
strbuf_splice(&sb, 0, 0, bp + 1, endp - (bp + 1));
scanp = bp;
endp = bp + 1;
+ ret = show_one_reflog_ent(&sb, fn, cb_data);
+ strbuf_reset(&sb);
+ if (ret)
+ break;
+ } else if (!pos) {
+ /*
+ * We are at the start of the buffer, and the
+ * start of the file; there is no previous
+ * line, and we have everything for this one.
+ * Process it, and we can end the loop.
+ */
+ strbuf_splice(&sb, 0, 0, buf, endp - buf);
+ ret = show_one_reflog_ent(&sb, fn, cb_data);
+ strbuf_reset(&sb);
+ break;
}
- ret = show_one_reflog_ent(&sb, fn, cb_data);
- strbuf_reset(&sb);
- if (ret)
+
+ if (bp == buf) {
+ /*
+ * We are at the start of the buffer, and there
+ * is more file to read backwards. Which means
+ * we are in the middle of a line. Note that we
+ * may get here even if *bp was a newline; that
+ * just means we are at the exact end of the
+ * previous line, rather than some spot in the
+ * middle.
+ *
+ * Save away what we have to be combined with
+ * the data from the next read.
+ */
+ strbuf_splice(&sb, 0, 0, buf, endp - buf);
break;
+ }
}
}
'
+# Triggering the bug detected by this test requires a newline to fall
+# exactly BUFSIZ-1 bytes from the end of the file. We don't know
+# what that value is, since it's platform dependent. However, if
+# we choose some value N, we also catch any D which divides N evenly
+# (since we will read backwards in chunks of D). So we choose 8K,
+# which catches glibc (with an 8K BUFSIZ) and *BSD (1K).
+#
+# Each line is 114 characters, so we need 75 to still have a few before the
+# last 8K. The 89-character padding on the final entry lines up our
+# newline exactly.
+test_expect_success 'parsing reverse reflogs at BUFSIZ boundaries' '
+ git checkout -b reflogskip &&
+ z38=00000000000000000000000000000000000000 &&
+ ident="abc <xyz> 0000000001 +0000" &&
+ for i in $(test_seq 1 75); do
+ printf "$z38%02d $z38%02d %s\t" $i $(($i+1)) "$ident" &&
+ if test $i = 75; then
+ for j in $(test_seq 1 89); do
+ printf X
+ done
+ else
+ printf X
+ fi &&
+ printf "\n"
+ done >.git/logs/refs/heads/reflogskip &&
+ git rev-parse reflogskip@{73} >actual &&
+ echo ${z38}03 >expect &&
+ test_cmp expect actual
+'
+
test_done