Functions
int	dlog_print (log_priority prio, const char tag, const char fmt,...)
	Send log with priority and tag.
int	dlog_vprint (log_priority prio, const char tag, const char fmt, va_list ap)
	Send log with priority, tag and va_list.

The Dlog API provides functions for sending log output.

Required Header

#include <dlog.h>

Overview

Sending log message to circular buffer. dlog APIs include Priority and Tag. By using priority and Tag, we can easily filtered messages what we want to see.

priority

priority level indicates the urgency of log message

Priority	Description
DLOG_DEBUG	Debug messasge. - Log message which developer want to check.
DLOG_INFO	Information message - Normal operational messages. above of this priority will always be logged.
DLOG_WARN	Warning messages - Not an error, but indication that an error will occur if action is not taken.
DLOG_ERROR	Error message - Indicate error.

Marco example for useful usage

The dlog APIs can be used by defining own macros. The macros can be defined like below examples. Thus, developers can use appropriate method as a matter of convenience.

#undef LOG_TAG
#define LOG_TAG "APP_TAG"

#define LOGI(fmt, arg...) \
    ({ do { \
        dlog_print(DLOG_INFO, LOG_TAG, "%s: %s(%d) > " fmt, __MODULE__, __func__, __LINE__, ##arg); \
    } while (0); })
#define LOGW(fmt, arg...) \
        ({ do { \
            dlog_print(DLOG_WARN, LOG_TAG, "%s: %s(%d) > " fmt, __MODULE__, __func__, __LINE__, ##arg); \
        } while (0); })
#define LOGE(fmt, arg...) \
        ({ do { \
            dlog_print(DLOG_ERROR, LOG_TAG, "%s: %s(%d) > " fmt, __MODULE__, __func__, __LINE__, ##arg); \
        } while (0); })

dlogutil

Introduction

You can use dlogutil command to view and follow the contents of the log buffers. The general usage is :

dlogutil [<option>] ... [<filter-spec>] ...

Filtering log output

Every log message has a tag and a priority associated with it. Filter expression follows this format tag:priority where tag indicates the tag of interest and priority indicates the minimum level of priority to report for that tag. You can add any number of tag:priority specifications in a single filter expression. The tag of a log message is a short indicating the system component from which the message originates The priority is one of the following character values, orderd from lowest to highest priority:
D - debug
I - info
W - warning
E - Error

for example, if you want to see MY_APP tag and above of debug priority,

# dlogutil MY_APP:D

if you want to see all log message above of info priority.

# dlogutil *:I

List of logutil command options

Option	Description
-b <buffer>	Alternate log buffer. The main buffer is used by default buffer.
-c	Clears the entire log and exits
-d	Dumps the log and exits.
-f <filename>	Writes log to filename. The default is stdout
-g	Print the size of the specified log buffer and exits.
-n <count>	Sets the maximum number of rotated logs to count. The default value is 4. Requires the -r option
-r <Kbytes>	Rotates the log file every Kbytes of output. The default value is 16. Requires the -f option.
-s	Sets the default filter spec to silent.
-v <format>	Sets the output format for log messages. The default is brief format.

>>>>>>> mobile

Enumeration Type Documentation

enum dlog_error_e

Enumeration for Dlog Error.

Since :: 2.3

Enumerator:

DLOG_ERROR_NONE	Successful
DLOG_ERROR_INVALID_PARAMETER	Invalid parameter
DLOG_ERROR_NOT_PERMITTED	Operation not permitted

enum log_priority

log priority values, in ascending priority order.

Since :: 2.3

Enumerator:

DLOG_UNKNOWN	Keep this always at the start
DLOG_DEFAULT	Default
DLOG_VERBOSE	Verbose
DLOG_DEBUG	Debug
DLOG_INFO	Info
DLOG_WARN	Warning
DLOG_ERROR	Error
DLOG_FATAL	Fatal
DLOG_SILENT	Silent
DLOG_PRIO_MAX	Keep this always at the end.

Function Documentation

int dlog_print	(	log_priority	prio,
		const char *	tag,
		const char *	fmt,
			...
	)

Send log with priority and tag.

for application

Since :: 2.3

Parameters:

[in]	prio	log_priority
[in]	tag	tag
[in]	fmt	format string

Returns:: On success, the function returns the number of bytes written. On error, a negative errno-style error code

Return values:

DLOG_ERROR_INVALID_PARAMETER	Invalid parameter
DLOG_ERROR_NOT_PERMITTED	Operation not permitted

Precondition:: none

Postcondition:: none

See also:

dlog_vprint

#include<dlog.h>
int main(void)
{
    int integer = 21;
    char string[] = "test dlog";

    dlog_print(DLOG_INFO, "USR_TAG", "test dlog");
    dlog_print(DLOG_INFO, "USR_TAG", "%s, %d", string, integer);
    return 0;
}

int dlog_vprint	(	log_priority	prio,
		const char *	tag,
		const char *	fmt,
		va_list	ap
	)

Send log with priority, tag and va_list.