From af191b4364ebecef36f0fdf120fa99273c134000 Mon Sep 17 00:00:00 2001
From: Alex Denes <caskd@redxen.eu>
Date: Sat, 9 Jan 2021 21:28:10 +0000
Subject: [PATCH] BUGFIX: Don't overwrite the FIFO buffer we're parsing

---
 src/main.c | 42 ++++++++++++++++++++++--------------------
 1 file changed, 22 insertions(+), 20 deletions(-)

diff --git a/src/main.c b/src/main.c
index 62ff16f..8e3a348 100644
--- a/src/main.c
+++ b/src/main.c
@@ -153,7 +153,6 @@ main(int argc, char* argv[])
 	setup_signals();
 	for (;;) {
 		ctime = time(NULL);
-		LOG(LOG_DEBUG, "Current time is: %lu", ctime);
 		if (connection.info.state == CONN_IDLE) nanosleep(&sleep, NULL);
 		if (!run || connection.info.state == CONN_CLOSING) {
 			signed long temp;
@@ -287,28 +286,32 @@ main(int argc, char* argv[])
 			}
 			if (buf.fifo.fd != -1) {
 				ssize_t brd, len;
-				/* Buffer writer */
+				/* FIFO reader */
 				if ((brd =
 				         read(buf.fifo.fd, buf.fifo.buffer + buf.fifo.append_pos, sizeof(buf.fifo.buffer) - buf.fifo.append_pos - 1))
 				    > 0) {
 					*(buf.fifo.buffer + (buf.fifo.append_pos += (size_t) brd)) = '\0';
-					LOG(LOG_DEBUG, "Read %li bytes from FIFO. Now appending at %li", brd, buf.fifo.append_pos);
+					LOG(LOG_DEBUG,
+					    "Read %li bytes from FIFO buffer. Now appending at %li with \"%s\" so far.",
+					    brd,
+					    buf.fifo.append_pos,
+					    buf.fifo.buffer);
+					connection.info.state = CONN_ACTIVE;
 				} else if (brd == -1 && errno != EAGAIN && errno != EWOULDBLOCK && errno != EINTR) {
-					LOG(LOG_ERROR, "Failed to read FIFO fifo. " ERRNOFMT, strerror(errno), errno);
+					LOG(LOG_ERROR, "Failed to read FIFO buffer. " ERRNOFMT, strerror(errno), errno);
 					connection.info.state = CONN_RECONNECTING;
 					continue;
 				}
 
 				memset((void*) &buffer, '\0', sizeof(IRC_Message));
 				if ((len = get_buffer_line(buf.fifo.buffer)) > 0) {
-					LOG(LOG_DEBUG, "Got FIFO message: %s", buf.fifo.buffer);
+					LOG(LOG_DEBUG, "Got IRC message: %s", buf.fifo.buffer);
 					if (Tok_mesg(buf.fifo.buffer, &buffer) == 1) {
-						LOG(LOG_DEBUG, "%s", "Tokenized FIFO message successfully.");
 						signed long temp;
-						if ((temp = Assm_mesg(buf.fifo.buffer, &buffer, sizeof(buf.fifo.buffer))) > 0) {
-							if (flush_buffer(buf.fifo.buffer, (size_t) temp, buf.send.fd) == -1) {
+						if ((temp = Assm_mesg(buf.send.buffer, &buffer, sizeof(buf.send.buffer))) > 0) {
+							if (flush_buffer(buf.send.buffer, (size_t) temp, buf.send.fd) == -1) {
 								LOG(LOG_WARN,
-								    "Couldn't send FIFO fifo to " ADDRFMT ". " ERRNOFMT,
+								    "Couldn't send FIFO contents to " ADDRFMT ". " ERRNOFMT,
 								    connection.data.address,
 								    connection.data.service,
 								    strerror(errno),
@@ -317,18 +320,17 @@ main(int argc, char* argv[])
 								continue;
 							}
 						}
-						for (long unsigned int x = 0; x < sizeof(buf.fifo.buffer) && *(buf.fifo.buffer + len + x); x++)
-							*(buf.fifo.buffer + x) = *(buf.fifo.buffer + x + len);
-						buf.fifo.append_pos -= (unsigned long) len;
-						*(buf.fifo.buffer + buf.fifo.append_pos) = '\0';
-					} else
-						LOG(LOG_WARN, "%s", "Received invalid IRC message (see RFC2812).");
-				} else if (len == -1) {
-					connection.info.state = CONN_RECONNECTING;
-				} else if (buf.fifo.append_pos == sizeof(buf.fifo.buffer) - 1) {
-					LOG(LOG_WARN, "%s. %s.", "FIFO buffer is full and no message could be parsed", "Discarding buffer");
+					} else {
+						LOG(LOG_WARN, "%s", "Received invalid IRC message on FIFO (see RFC2812).");
+					}
+					for (long unsigned int x = 0; x < sizeof(buf.fifo.buffer) && *(buf.fifo.buffer + len + x); x++)
+						*(buf.fifo.buffer + x) = *(buf.fifo.buffer + x + len);
+					buf.fifo.append_pos -= (unsigned long) len;
+					*(buf.fifo.buffer + buf.fifo.append_pos) = '\0';
+				} else if (buf.fifo.append_pos == sizeof(buf.fifo.fd) - 1) {
+					LOG(LOG_WARN, "%s.", "FIFO buffer is full and no message could be parsed. Cleared buffer.");
+					memset(buf.fifo.buffer, '\0', sizeof(buf.fifo));
 					buf.fifo.append_pos = 0;
-					*buf.fifo.buffer    = '\0';
 				}
 			} else {
 				char pathbuf[UIRCD_LIMITS_PATH];