diff options
| -rw-r--r-- | refs.c | 49 | ||||
| -rwxr-xr-x | t/t1410-reflog.sh | 30 |
2 files changed, 67 insertions, 12 deletions
@@ -3404,29 +3404,54 @@ int for_each_reflog_ent_reverse(const char *refname, each_reflog_ent_fn fn, void 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; + } } } if (!ret && sb.len) - ret = show_one_reflog_ent(&sb, fn, cb_data); + die("BUG: reverse reflog parser had leftover data"); fclose(logfp); strbuf_release(&sb); diff --git a/t/t1410-reflog.sh b/t/t1410-reflog.sh index 8cf446165e..779d4e3829 100755 --- a/t/t1410-reflog.sh +++ b/t/t1410-reflog.sh @@ -287,4 +287,34 @@ test_expect_success 'stale dirs do not cause d/f conflicts (reflogs off)' ' test_cmp expect actual ' +# 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 |