There are users which print time and date represented by content of
struct rtc_time in human readable format.
Instead of open coding that each time introduce %ptR[dt][rv] specifier.
Note, users have to select PRINTK_PEXT_TIMEDATE option in a Kconfig.
Cc: Arnd Bergmann <arnd@xxxxxxxx>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@xxxxxxxxxxx>
Cc: Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx>
Cc: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>
Cc: Guan Xuetao <gxt@xxxxxxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Jason Wessel <jason.wessel@xxxxxxxxxxxxx>
Cc: Jonathan Corbet <corbet@xxxxxxx>
Cc: Jonathan Hunter <jonathanh@xxxxxxxxxx>
Cc: Krzysztof Kozlowski <krzk@xxxxxxxxxx>
Cc: "Rafael J. Wysocki" <rjw@xxxxxxxxxxxxx>
Cc: Thierry Reding <thierry.reding@xxxxxxxxx>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
---
Documentation/core-api/printk-formats.rst | 31 +++++++
lib/Kconfig | 8 ++
lib/test_printf.c | 6 ++
lib/vsprintf.c | 145 ++++++++++++++++++++++++++++++
4 files changed, 190 insertions(+)
diff --git a/Documentation/core-api/printk-formats.rst b/Documentation/core-api/printk-formats.rst
index 934559b3c130..9aaf0858ddd4 100644
--- a/Documentation/core-api/printk-formats.rst
+++ b/Documentation/core-api/printk-formats.rst
@@ -412,6 +412,37 @@ Examples::
Passed by reference.
+Time and date
+-------------
+
+::
+
+ %pt[R] YYYY-mm-dd HH:MM:SS
+ %pt[R]d YYYY-mm-dd
+ %pt[R]t HH:MM:SS
+ %pt[R][dt]
+
+ R for struct rtc_time
+
+Note, users have to select PRINTK_PEXT_TIMEDATE option in a Kconfig.
+
+struct rtc_time
+~~~~~~~~~~~~~~~
+
+::
+
+ %ptR[dt][rv]
+
+For printing date and time as represented by struct rtc_time structure in
+human readable format.
+
+By default year will be incremented by 1900 and month by 1. Use %ptRr (raw)
+to suppress this behaviour. On the other hand when %ptRv is applied
+validation mechanism will be in use, i.e. numbers out of range will be
+replaced by ** or ****.
+
+Passed by reference.
+
struct clk
----------
diff --git a/lib/Kconfig b/lib/Kconfig
index e96089499371..e48cb7ba7beb 100644
--- a/lib/Kconfig
+++ b/lib/Kconfig
@@ -605,3 +605,11 @@ config GENERIC_CMPDI2
config GENERIC_UCMPDI2
bool
+
+#
+# %p optional extensions for vsnprintf().
+# Should be selected by users.
+#
+
+config PRINTK_PEXT_TIMEDATE
+ bool
diff --git a/lib/test_printf.c b/lib/test_printf.c
index cea592f402ed..54f8960ea531 100644
--- a/lib/test_printf.c
+++ b/lib/test_printf.c
@@ -398,6 +398,11 @@ struct_va_format(void)
{
}
+static void __init
+struct_rtc_time(void)
+{
+}
+
static void __init
struct_clk(void)
{
@@ -509,6 +514,7 @@ test_pointer(void)
uuid();
dentry();
struct_va_format();
+ struct_rtc_time();
struct_clk();
bitmap();
netdev_features();
diff --git a/lib/vsprintf.c b/lib/vsprintf.c
index 28d7aca6a805..90ea28aefc26 100644
--- a/lib/vsprintf.c
+++ b/lib/vsprintf.c
@@ -30,6 +30,7 @@
#include <linux/ioport.h>
#include <linux/dcache.h>
#include <linux/cred.h>
+#include <linux/rtc.h>
#include <linux/uuid.h>
#include <linux/of.h>
#include <net/addrconf.h>
@@ -709,6 +710,20 @@ static const struct printf_spec default_dec_spec = {
.precision = -1,
};
+static const struct printf_spec default_dec02_spec = {
+ .base = 10,
+ .field_width = 2,
+ .precision = -1,
+ .flags = ZEROPAD,
+};
+
+static const struct printf_spec default_dec04_spec = {
+ .base = 10,
+ .field_width = 4,
+ .precision = -1,
+ .flags = ZEROPAD,
+};
+
static noinline_for_stack
char *resource_string(char *buf, char *end, struct resource *res,
struct printf_spec spec, const char *fmt)
@@ -1443,6 +1458,132 @@ char *address_val(char *buf, char *end, const void *addr, const char *fmt)
return special_hex_number(buf, end, num, size);
}
+static noinline_for_stack
+char *date_str(char *buf, char *end, const struct rtc_time *tm, bool v, bool r)
+{
+ int year = tm->tm_year + (r ? 0 : 1900);
+ int mon = tm->tm_mon + (r ? 0 : 1);
+
+ if (unlikely(v && (unsigned int)tm->tm_year > 200))
+ buf = string(buf, end, "****", default_str_spec);
+ else
+ buf = number(buf, end, year, default_dec04_spec);
+
+ if (buf < end)
+ *buf = '-';
+ buf++;
+
+ if (unlikely(v && (unsigned int)tm->tm_mon > 11))
+ buf = string(buf, end, "**", default_str_spec);
+ else
+ buf = number(buf, end, mon, default_dec02_spec);
+
+ if (buf < end)
+ *buf = '-';
+ buf++;
+
+ if (unlikely(v && (unsigned int)tm->tm_mday > 31))
+ buf = string(buf, end, "**", default_str_spec);
+ else
+ buf = number(buf, end, tm->tm_mday, default_dec02_spec);
+
+ return buf;
+}
+
+static noinline_for_stack
+char *time_str(char *buf, char *end, const struct rtc_time *tm, bool v, bool r)
+{
+ if (unlikely(v && (unsigned int)tm->tm_hour > 24))
+ buf = string(buf, end, "**", default_str_spec);
+ else
+ buf = number(buf, end, tm->tm_hour, default_dec02_spec);
+
+ if (buf < end)
+ *buf = ':';
+ buf++;
+
+ if (unlikely(v && (unsigned int)tm->tm_min > 59))
+ buf = string(buf, end, "**", default_str_spec);
+ else
+ buf = number(buf, end, tm->tm_min, default_dec02_spec);
+
+ if (buf < end)
+ *buf = ':';
+ buf++;
+
+ if (unlikely(v && (unsigned int)tm->tm_sec > 59))
+ buf = string(buf, end, "**", default_str_spec);
+ else
+ buf = number(buf, end, tm->tm_sec, default_dec02_spec);
+
+ return buf;
+}
+
+static noinline_for_stack
+char *rtc_str(char *buf, char *end, const struct rtc_time *tm, const char *fmt)
+{
+ bool have_t = true, have_d = true;
+ bool validate = false;
+ bool raw = false;
+ int count = 1;
+ bool found;
+
+ switch (fmt[++count]) {
+ case 'd':
+ have_t = false;
+ break;
+ case 't':
+ have_d = false;
+ break;
+ }
+
+ /* No %pt[dt] supplied */
+ if (have_d && have_t)
+ --count;
+
+ found = true;
+ do {
+ switch (fmt[++count]) {
+ case 'r':
+ raw = true;
+ break;
+ case 'v':
+ validate = true;
+ break;
+ default:
+ found = false;
+ break;
+ }
+ } while (found);
+
+ if (have_d)
+ buf = date_str(buf, end, tm, validate, raw);
+ if (have_d && have_t) {
+ if (buf < end)
+ *buf = ' ';
+ buf++;
+ }
+ if (have_t)
+ buf = time_str(buf, end, tm, validate, raw);
+
+ return buf;
+}
+
+static noinline_for_stack
+char *timeanddate(char *buf, char *end, void *ptr, const char *fmt)
+{
+ if (!IS_ENABLED(CONFIG_PRINTK_PEXT_TIMEDATE))
+ return string(buf, end, NULL, default_str_spec);
+
+ switch (fmt[1]) {
+ case 'R':
+ return rtc_str(buf, end, (const struct rtc_time *)ptr, fmt);
+ default:
+ break;
+ }
+ return special_hex_number(buf, end, (unsigned long)ptr, sizeof(void *));
+}
+
static noinline_for_stack
char *clock(char *buf, char *end, struct clk *clk, struct printf_spec spec,
const char *fmt)
@@ -1776,6 +1917,8 @@ static char *ptr_to_id(char *buf, char *end, void *ptr, struct printf_spec spec)
* - 'd[234]' For a dentry name (optionally 2-4 last components)
* - 'D[234]' Same as 'd' but for a struct file
* - 'g' For block_device name (gendisk + partition number)
+ * - 't[R][dt][rv]' For time and date as represented:
+ * R struct rtc_time
* - 'C' For a clock, it prints the name (Common Clock Framework) or address
* (legacy clock framework) of the clock
* - 'Cn' For a clock, it prints the name (Common Clock Framework) or address
@@ -1906,6 +2049,8 @@ char *pointer(const char *fmt, char *buf, char *end, void *ptr,
return address_val(buf, end, ptr, fmt);
case 'd':
return dentry_name(buf, end, ptr, spec, fmt);
+ case 't':
+ return timeanddate(buf, end, ptr, fmt);
case 'C':
return clock(buf, end, ptr, spec, fmt);
case 'D':
--
2.15.1
