diff --git a/man/systemd.journal-fields.xml b/man/systemd.journal-fields.xml
index a0771f3c13..4d35cfb6dc 100644
--- a/man/systemd.journal-fields.xml
+++ b/man/systemd.journal-fields.xml
@@ -347,15 +347,16 @@
_LINE_BREAK=
- Only applies to _TRANSPORT=stdout records: indicates that the log message in the
- standard output/error stream was not terminated with a normal newline character (\n,
- i.e. ASCII 10). Specifically, when set this field is one of (in case the line was
- terminated by a NUL byte), (in case the maximum log line length was reached, as
- configured with LineMax= in
- journald.conf5) or
- (if this was the last log record of a stream and the stream ended without a final
- newline character). Note that this record is not generated when a normal newline character was used for
- marking the log line end.
+ Only applies to _TRANSPORT=stdout records: indicates that the log message
+ in the standard output/error stream was not terminated with a normal newline character
+ (\n, i.e. ASCII 10). Specifically, when set this field is one of
+ (in case the line was terminated by a NUL byte), (in
+ case the maximum log line length was reached, as configured with LineMax= in
+ journald.conf5),
+ (if this was the last log record of a stream and the stream ended without a
+ final newline character), or (if the process which generated the log
+ output changed in the middle of a line). Note that this record is not generated when a normal
+ newline character was used for marking the log line end.
diff --git a/src/journal/journald-stream.c b/src/journal/journald-stream.c
index 4dadbd62be..241e2572e6 100644
--- a/src/journal/journald-stream.c
+++ b/src/journal/journald-stream.c
@@ -58,6 +58,9 @@ typedef enum LineBreak {
LINE_BREAK_NUL,
LINE_BREAK_LINE_MAX,
LINE_BREAK_EOF,
+ LINE_BREAK_PID_CHANGE,
+ _LINE_BREAK_MAX,
+ _LINE_BREAK_INVALID = -1,
} LineBreak;
struct StdoutStream {
@@ -238,7 +241,11 @@ fail:
return log_error_errno(r, "Failed to save stream data %s: %m", s->state_file);
}
-static int stdout_stream_log(StdoutStream *s, const char *p, LineBreak line_break) {
+static int stdout_stream_log(
+ StdoutStream *s,
+ const char *p,
+ LineBreak line_break) {
+
struct iovec *iovec;
int priority;
char syslog_priority[] = "PRIORITY=\0";
@@ -250,6 +257,9 @@ static int stdout_stream_log(StdoutStream *s, const char *p, LineBreak line_brea
assert(s);
assert(p);
+ assert(line_break >= 0);
+ assert(line_break < _LINE_BREAK_MAX);
+
if (s->context)
(void) client_context_maybe_refresh(s->server, s->context, NULL, NULL, 0, NULL, USEC_INFINITY);
else if (pid_is_valid(s->ucred.pid)) {
@@ -301,17 +311,20 @@ static int stdout_stream_log(StdoutStream *s, const char *p, LineBreak line_brea
iovec[n++] = IOVEC_MAKE_STRING(syslog_identifier);
}
- if (line_break != LINE_BREAK_NEWLINE) {
- const char *c;
+ static const char * const line_break_field_table[_LINE_BREAK_MAX] = {
+ [LINE_BREAK_NEWLINE] = NULL, /* Do not add field if traditional newline */
+ [LINE_BREAK_NUL] = "_LINE_BREAK=nul",
+ [LINE_BREAK_LINE_MAX] = "_LINE_BREAK=line-max",
+ [LINE_BREAK_EOF] = "_LINE_BREAK=eof",
+ [LINE_BREAK_PID_CHANGE] = "_LINE_BREAK=pid-change",
+ };
- /* If this log message was generated due to an uncommon line break then mention this in the log
- * entry */
+ const char *c = line_break_field_table[line_break];
- c = line_break == LINE_BREAK_NUL ? "_LINE_BREAK=nul" :
- line_break == LINE_BREAK_LINE_MAX ? "_LINE_BREAK=line-max" :
- "_LINE_BREAK=eof";
+ /* If this log message was generated due to an uncommon line break then mention this in the log
+ * entry */
+ if (c)
iovec[n++] = IOVEC_MAKE_STRING(c);
- }
message = strjoin("MESSAGE=", p);
if (message)
@@ -322,8 +335,8 @@ static int stdout_stream_log(StdoutStream *s, const char *p, LineBreak line_brea
}
static int stdout_stream_line(StdoutStream *s, char *p, LineBreak line_break) {
- int r;
char *orig;
+ int r;
assert(s);
assert(p);
@@ -332,10 +345,9 @@ static int stdout_stream_line(StdoutStream *s, char *p, LineBreak line_break) {
p = strstrip(p);
/* line breaks by NUL, line max length or EOF are not permissible during the negotiation part of the protocol */
- if (line_break != LINE_BREAK_NEWLINE && s->state != STDOUT_STREAM_RUNNING) {
- log_warning("Control protocol line not properly terminated.");
- return -EINVAL;
- }
+ if (line_break != LINE_BREAK_NEWLINE && s->state != STDOUT_STREAM_RUNNING)
+ return log_warning_errno(SYNTHETIC_ERRNO(EINVAL),
+ "Control protocol line not properly terminated.");
switch (s->state) {
@@ -425,21 +437,43 @@ static int stdout_stream_line(StdoutStream *s, char *p, LineBreak line_break) {
assert_not_reached("Unknown stream state");
}
-static int stdout_stream_scan(StdoutStream *s, bool force_flush) {
- char *p;
- size_t remaining;
+static int stdout_stream_found(
+ StdoutStream *s,
+ char *p,
+ size_t l,
+ LineBreak line_break) {
+
+ char saved;
int r;
assert(s);
+ assert(p);
- p = s->buffer;
- remaining = s->length;
+ /* Let's NUL terminate the specified buffer for this call, and revert back afterwards */
+ saved = p[l];
+ p[l] = 0;
+ r = stdout_stream_line(s, p, line_break);
+ p[l] = saved;
- /* XXX: This function does nothing if (s->length == 0) */
+ return r;
+}
+
+static int stdout_stream_scan(
+ StdoutStream *s,
+ char *p,
+ size_t remaining,
+ LineBreak force_flush,
+ size_t *ret_consumed) {
+
+ size_t consumed = 0;
+ int r;
+
+ assert(s);
+ assert(p);
for (;;) {
LineBreak line_break;
- size_t skip;
+ size_t skip, found;
char *end1, *end2;
end1 = memchr(p, '\n', remaining);
@@ -447,43 +481,40 @@ static int stdout_stream_scan(StdoutStream *s, bool force_flush) {
if (end2) {
/* We found a NUL terminator */
- skip = end2 - p + 1;
+ found = end2 - p;
+ skip = found + 1;
line_break = LINE_BREAK_NUL;
} else if (end1) {
/* We found a \n terminator */
- *end1 = 0;
- skip = end1 - p + 1;
+ found = end1 - p;
+ skip = found + 1;
line_break = LINE_BREAK_NEWLINE;
} else if (remaining >= s->server->line_max) {
/* Force a line break after the maximum line length */
- *(p + s->server->line_max) = 0;
- skip = remaining;
+ found = skip = s->server->line_max;
line_break = LINE_BREAK_LINE_MAX;
} else
break;
- r = stdout_stream_line(s, p, line_break);
+ r = stdout_stream_found(s, p, found, line_break);
if (r < 0)
return r;
- remaining -= skip;
p += skip;
+ consumed += skip;
+ remaining -= skip;
}
- if (force_flush && remaining > 0) {
- p[remaining] = 0;
- r = stdout_stream_line(s, p, LINE_BREAK_EOF);
+ if (force_flush >= 0 && remaining > 0) {
+ r = stdout_stream_found(s, p, remaining, force_flush);
if (r < 0)
return r;
- p += remaining;
- remaining = 0;
+ consumed += remaining;
}
- if (p > s->buffer) {
- memmove(s->buffer, p, remaining);
- s->length = remaining;
- }
+ if (ret_consumed)
+ *ret_consumed = consumed;
return 0;
}
@@ -491,10 +522,11 @@ static int stdout_stream_scan(StdoutStream *s, bool force_flush) {
static int stdout_stream_process(sd_event_source *es, int fd, uint32_t revents, void *userdata) {
CMSG_BUFFER_TYPE(CMSG_SPACE(sizeof(struct ucred))) control;
StdoutStream *s = userdata;
+ size_t limit, consumed;
struct ucred *ucred;
struct iovec iovec;
- size_t limit;
ssize_t l;
+ char *p;
int r;
struct msghdr msghdr = {
@@ -511,8 +543,8 @@ static int stdout_stream_process(sd_event_source *es, int fd, uint32_t revents,
goto terminate;
}
- /* If the buffer is full already (discounting the extra NUL we need), add room for another 1K */
- if (s->length + 1 >= s->allocated) {
+ /* If the buffer is almost full, add room for another 1K */
+ if (s->length + 512 >= s->allocated) {
if (!GREEDY_REALLOC(s->buffer, s->allocated, s->length + 1 + 1024)) {
log_oom();
goto terminate;
@@ -522,7 +554,7 @@ static int stdout_stream_process(sd_event_source *es, int fd, uint32_t revents,
/* Try to make use of the allocated buffer in full, but never read more than the configured line size. Also,
* always leave room for a terminating NUL we might need to add. */
limit = MIN(s->allocated - 1, s->server->line_max);
-
+ assert(s->length <= limit);
iovec = IOVEC_MAKE(s->buffer + s->length, limit - s->length);
l = recvmsg(s->fd, &msghdr, MSG_DONTWAIT|MSG_CMSG_CLOEXEC);
@@ -536,32 +568,42 @@ static int stdout_stream_process(sd_event_source *es, int fd, uint32_t revents,
cmsg_close_all(&msghdr);
if (l == 0) {
- stdout_stream_scan(s, true);
+ (void) stdout_stream_scan(s, s->buffer, s->length, /* force_flush = */ LINE_BREAK_EOF, NULL);
goto terminate;
}
- /* Invalidate the context if the pid of the sender changed. This happens when a forked process
- * inherits stdout / stderr from a parent. In this case getpeercred returns the ucred of the parent,
- * which can be invalid if the parent has exited in the meantime.
- */
+ /* Invalidate the context if the PID of the sender changed. This happens when a forked process
+ * inherits stdout/stderr from a parent. In this case getpeercred() returns the ucred of the parent,
+ * which can be invalid if the parent has exited in the meantime. */
ucred = CMSG_FIND_DATA(&msghdr, SOL_SOCKET, SCM_CREDENTIALS, struct ucred);
if (ucred && ucred->pid != s->ucred.pid) {
- /* force out any previously half-written lines from a different process, before we switch to
+ /* Force out any previously half-written lines from a different process, before we switch to
* the new ucred structure for everything we just added */
- r = stdout_stream_scan(s, true);
+ r = stdout_stream_scan(s, s->buffer, s->length, /* force_flush = */ LINE_BREAK_PID_CHANGE, NULL);
if (r < 0)
goto terminate;
- s->ucred = *ucred;
- client_context_release(s->server, s->context);
- s->context = NULL;
+ s->context = client_context_release(s->server, s->context);
+
+ p = s->buffer + s->length;
+ } else {
+ p = s->buffer;
+ l += s->length;
}
- s->length += l;
- r = stdout_stream_scan(s, false);
+ /* Always copy in the new credentials */
+ if (ucred)
+ s->ucred = *ucred;
+
+ r = stdout_stream_scan(s, p, l, _LINE_BREAK_INVALID, &consumed);
if (r < 0)
goto terminate;
+ /* Move what wasn't consumed to the front of the buffer */
+ assert(consumed <= (size_t) l);
+ s->length = l - consumed;
+ memmove(s->buffer, p + consumed, s->length);
+
return 1;
terminate:
diff --git a/test/units/testsuite-04.sh b/test/units/testsuite-04.sh
index 6e7627313c..3dce73b778 100755
--- a/test/units/testsuite-04.sh
+++ b/test/units/testsuite-04.sh
@@ -87,6 +87,18 @@ journalctl -b -o export -t "$ID" --output-fields=_PID | grep '^_PID=' >/output
grep -q "^_PID=$PID" /output
grep -vq "^_PID=$PID" /output
+# https://github.com/systemd/systemd/issues/15654
+ID=$(journalctl --new-id128 | sed -n 2p)
+printf "This will\nusually fail\nand be truncated\n">/expected
+systemd-cat -t "$ID" /bin/sh -c 'env echo -n "This will";echo;env echo -n "usually fail";echo;env echo -n "and be truncated";echo;'
+journalctl --sync
+journalctl -b -o cat -t "$ID" >/output
+cmp /expected /output
+[[ $(journalctl -b -o cat -t "$ID" --output-fields=_TRANSPORT | grep -Pc "^stdout$") -eq 3 ]]
+[[ $(journalctl -b -o cat -t "$ID" --output-fields=_LINE_BREAK | grep -Pc "^pid-change$") -eq 3 ]]
+[[ $(journalctl -b -o cat -t "$ID" --output-fields=_PID | sort -u | grep -c "^.*$") -eq 3 ]]
+[[ $(journalctl -b -o cat -t "$ID" --output-fields=MESSAGE | grep -Pc "^(This will|usually fail|and be truncated)$") -eq 3 ]]
+
# Add new tests before here, the journald restarts below
# may make tests flappy.