From 9a44a20a9d25f7e5d38ff943fbbd51d0f305ce3f Mon Sep 17 00:00:00 2001 From: Kevin O'Connor Date: Fri, 13 Jan 2017 12:10:00 -0500 Subject: command: Check for reentrant calls to sendf() Allow sendf() to be called from irq and timer context - check for the case where sendf() is called while already in sendf() and simply discard those messages. This makes it safe to use output() debugging calls even in irq and timer context. Signed-off-by: Kevin O'Connor --- src/command.c | 15 ++++++++++++++- 1 file changed, 14 insertions(+), 1 deletion(-) (limited to 'src/command.c') diff --git a/src/command.c b/src/command.c index f11bfcc8..069dfe57 100644 --- a/src/command.c +++ b/src/command.c @@ -114,11 +114,22 @@ error: void _sendf(uint8_t parserid, ...) { + static uint8_t in_sendf; + irqstatus_t flag = irq_save(); + if (in_sendf) { + // This sendf call was made from an irq handler while the main + // code was already in sendf - just drop this sendf request. + irq_restore(flag); + return; + } + in_sendf = 1; + irq_restore(flag); + const struct command_encoder *cp = &command_encoders[parserid]; uint8_t max_size = READP(cp->max_size); char *buf = console_get_output(max_size + MESSAGE_MIN); if (!buf) - return; + goto done; char *p = &buf[MESSAGE_HEADER_SIZE]; if (max_size) { char *maxend = &p[max_size]; @@ -182,6 +193,8 @@ _sendf(uint8_t parserid, ...) *p++ = crc; *p++ = MESSAGE_SYNC; console_push_output(msglen); +done: + in_sendf = 0; return; error: shutdown("Message encode error"); -- cgit v1.2.3-70-g09d2