From a001e41dd836cf99e12ed3fefb094066e220d149 Mon Sep 17 00:00:00 2001 From: Jade Mattsson Date: Thu, 24 Oct 2024 12:05:52 +1100 Subject: [PATCH] Add workaround for silently dropped console output. --- components/modules/console.c | 14 +++++++++++--- 1 file changed, 11 insertions(+), 3 deletions(-) diff --git a/components/modules/console.c b/components/modules/console.c index 8cda2aea..d92c6a92 100644 --- a/components/modules/console.c +++ b/components/modules/console.c @@ -171,7 +171,17 @@ static int retrying_write(const char *buf, size_t len) size_t written = 0; while (written < len) { - size_t n = fwrite(buf + written, 1, len - written, stdout); + // At least the USB-Serial-JTAG appears to silently drop characters + // sometimes when writing more than 255 bytes, so we break such strings + // up into multiple calls as a workaround. + const size_t MAX_LEN = 255; + size_t left = len - written; + size_t to_write = left > MAX_LEN ? MAX_LEN : left; + size_t n = fwrite(buf + written, 1, to_write, stdout); + // Additionally, we have to explicitly flush after each chunk we've written. + fflush(stdout); + fsync(fileno(stdout)); + if (n > 0) written += n; else if (ferror(stdout)) @@ -224,8 +234,6 @@ static int console_write(lua_State *L) retrying_write(&ch, 1); } } - fflush(stdout); - fsync(fileno(stdout)); return 0; }