From 5210225f256d01938960d439bff9d809c2ff1809 Mon Sep 17 00:00:00 2001 From: Jiang Xin Date: Thu, 17 Jun 2021 11:17:24 +0800 Subject: [PATCH] sideband: don't lose clear-to-eol at packet boundary When "demultiplex_sideband()" sees a nonempty message ending with CR or LF on the sideband #2, it adds "suffix" string to clear to the end of the current line, which helps when relaying a progress display whose records are terminated with CRs. But if it sees a single LF, no clear-to-end suffix should be appended, because this single LF is used to end the progress display by moving to the next line, and the final progress display above should be preserved. However, the code forgot that depending on the length of the payload line, such a CR may fall exactly at the packet boundary and the number of bytes before the CR from the beginning of the packet could be zero. In such a case, the message that was terminated by the CR were leftover in the "scratch" buffer in the previous call to the function and we still need to clear to the end of the current line. Helped-by: Junio C Hamano Helped-by: Nicolas Pitre Signed-off-by: Jiang Xin Signed-off-by: Junio C Hamano --- sideband.c | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+) diff --git a/sideband.c b/sideband.c index 6f9e0267320..85bddfdcd4f 100644 --- a/sideband.c +++ b/sideband.c @@ -183,8 +183,31 @@ int demultiplex_sideband(const char *me, int status, while ((brk = strpbrk(b, "\n\r"))) { int linelen = brk - b; + /* + * For message accross packet boundary, there would have + * a nonempty "scratch" buffer from last call of this + * function, and there may have a leading CR/LF in "buf". + * For this case we should add a clear-to-eol suffix to + * clean leftover letters we previously have written on + * the same line. + */ + if (scratch->len && !linelen) + strbuf_addstr(scratch, suffix); + if (!scratch->len) strbuf_addstr(scratch, DISPLAY_PREFIX); + + /* + * A use case that we should not add clear-to-eol suffix + * to empty lines: + * + * For progress reporting we may receive a bunch of + * percentage updates followed by '\r' to remain on the + * same line, and at the end receive a single '\n' to + * move to the next line. We should preserve the final + * status report line by not appending clear-to-eol + * suffix to this single line break. + */ if (linelen > 0) { maybe_colorize_sideband(scratch, b, linelen); strbuf_addstr(scratch, suffix);