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Date: Thu, 6 Dec 2012 18:06:04 +0100
From: Jan H. Schönherr <schnhrr@...tu-berlin.de>
To: Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
Kay Sievers <kay@...y.org>
Cc: linux-kernel@...r.kernel.org, Joe Perches <joe@...ches.com>,
Andrew Morton <akpm@...ux-foundation.org>,
Stephen Rothwell <sfr@...b.auug.org.au>,
Jan H. Schönherr <schnhrr@...tu-berlin.de>
Subject: [PATCH v2 07/14] printk: let cont_print_text() reuse existing code
The functionality of cont_print_text() also exists within
msg_print_text(). The major difference is that cont_print_text()
currently fails to print timestamps for multi-line strings from the
second line on.
In order to be able to use msg_print_text() from cont_print_text(),
create a more general version print_text() that can also be used with
the continuation buffer and has the ability to start at a specific
position within the message and to track that position.
Signed-off-by: Jan H. Schönherr <schnhrr@...tu-berlin.de>
---
v2:
- moved an already needed check from a later patch to this patch
- fixed a bug, where a single newline at the end of the buffer might get
skipped
- realized the utilization of msg_print_text() functionality completely
different: we now pass lots of parameters instead of restructuring
struct cont, which results in more readable code
---
kernel/printk.c | 82 ++++++++++++++++++++++++++++++++-------------------------
1 file changed, 46 insertions(+), 36 deletions(-)
diff --git a/kernel/printk.c b/kernel/printk.c
index 4f3c355..b6c4eae 100644
--- a/kernel/printk.c
+++ b/kernel/printk.c
@@ -853,10 +853,11 @@ static size_t print_time(u64 ts, char *buf)
(unsigned long)ts, rem_nsec / 1000);
}
-static size_t print_prefix(const struct log *msg, bool syslog, char *buf)
+static size_t print_prefix(u8 facility, u8 level, u64 ts_nsec, bool syslog,
+ char *buf)
{
size_t len = 0;
- unsigned int prefix = (msg->facility << 3) | msg->level;
+ unsigned int prefix = (facility << 3) | level;
if (syslog) {
if (buf) {
@@ -872,25 +873,33 @@ static size_t print_prefix(const struct log *msg, bool syslog, char *buf)
}
}
- len += print_time(msg->ts_nsec, buf ? buf + len : NULL);
+ len += print_time(ts_nsec, buf ? buf + len : NULL);
return len;
}
-static size_t msg_print_text(const struct log *msg, enum log_flags prev,
- bool syslog, char *buf, size_t size)
+static size_t print_text(const char *text, size_t text_size, size_t *offset,
+ enum log_flags flags, enum log_flags prev,
+ u8 facility, u8 level, u64 ts_nsec, bool syslog,
+ char *buf, size_t size)
{
- const char *text = log_text(msg);
- size_t text_size = msg->text_len;
bool prefix = true;
bool newline = true;
size_t len = 0;
+ size_t prefix_len = 0;
- if (!(prev & LOG_NEWLINE) && !(msg->flags & LOG_PREFIX))
+ if (!(prev & LOG_NEWLINE) && !(flags & LOG_PREFIX))
prefix = false;
- if (!(msg->flags & LOG_NEWLINE))
+ if (!(flags & LOG_NEWLINE))
newline = false;
+ if (offset) {
+ text += *offset;
+ text_size -= *offset;
+ if (*offset)
+ prefix = false;
+ }
+
if (!(prev & LOG_NEWLINE) && prefix) {
if (buf)
buf[len] = '\n';
@@ -909,22 +918,25 @@ static size_t msg_print_text(const struct log *msg, enum log_flags prev,
text_len = text_size;
}
+ if (prefix && !prefix_len)
+ prefix_len = print_prefix(facility, level, ts_nsec,
+ syslog, NULL);
if (buf) {
- if (print_prefix(msg, syslog, NULL) +
- text_len + 1 >= size - len)
+ if (prefix_len + text_len + 1 >= size - len)
break;
if (prefix)
- len += print_prefix(msg, syslog, buf + len);
+ len += print_prefix(facility, level, ts_nsec,
+ syslog, buf + len);
memcpy(buf + len, text, text_len);
len += text_len;
+ if (offset)
+ *offset += text_len + (next ? 1 : 0);
if (next || newline)
buf[len++] = '\n';
} else {
/* SYSLOG_ACTION_* buffer size only calculation */
- if (prefix)
- len += print_prefix(msg, syslog, NULL);
- len += text_len;
+ len += prefix_len + text_len;
if (next || newline)
len++;
}
@@ -936,6 +948,15 @@ static size_t msg_print_text(const struct log *msg, enum log_flags prev,
return len;
}
+static size_t msg_print_text(const struct log *msg,
+ enum log_flags prev,
+ bool syslog, char *buf, size_t size)
+{
+ return print_text(log_text(msg), msg->text_len, NULL, msg->flags, prev,
+ msg->facility, msg->level, msg->ts_nsec, syslog,
+ buf, size);
+}
+
static int syslog_print(char __user *buf, int size)
{
char *text;
@@ -1458,31 +1479,20 @@ static bool cont_add(int facility, int level, enum log_flags flags,
static size_t cont_print_text(char *text, size_t size)
{
size_t textlen = 0;
- size_t len;
- if (cont.cons == 0 && (console_prev & LOG_NEWLINE ||
- cont.flags & LOG_PREFIX)) {
- if (!(console_prev & LOG_NEWLINE))
- text[textlen++] = '\n';
- textlen += print_time(cont.ts_nsec, text + textlen);
- size -= textlen;
- }
-
- len = cont.len - cont.cons;
- if (len > 0) {
- if (len+1 > size)
- len = size-1;
- memcpy(text + textlen, cont.buf + cont.cons, len);
- textlen += len;
- cont.cons = cont.len;
+ if (cont.len == cont.cons) {
+ /* Not even a newline to print? */
+ if (!(cont.flags & LOG_NEWLINE))
+ goto out;
}
- if (cont.flushed) {
- if (cont.flags & LOG_NEWLINE)
- text[textlen++] = '\n';
- /* got everything, release buffer */
+ textlen = print_text(cont.buf, cont.len, &cont.cons, cont.flags,
+ console_prev, cont.facility, cont.level,
+ cont.ts_nsec, false, text, size);
+out:
+ if (cont.flushed)
cont.len = 0;
- }
+
return textlen;
}
--
1.8.0.1.20.g7c65b2e.dirty
--
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