utils.c File Reference

Utilities and helpers. More...

#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#include <errno.h>
#include <fcntl.h>
#include <sys/file.h>
#include <sys/types.h>
#include <unistd.h>
#include "utils.h"
#include "debug.h"

Include dependency graph for utils.c:

Functions
gint64	janus_get_monotonic_time (void)
	Helper to retrieve the system monotonic time, as Glib's g_get_monotonic_time may not be available (only since 2.28) More...
gint64	janus_get_real_time (void)
	Helper to retrieve the system real time, as Glib's g_get_real_time may not be available (only since 2.28) More...
gboolean	janus_is_true (const char *value)
	Helper to parse yes/no|true/false configuration values. More...
gboolean	janus_strcmp_const_time (const void *str1, const void *str2)
	Helper to compare strings in constant time. More...
guint32	janus_random_uint32 (void)
	Helper to generate random 32-bit unsigned integers (useful for SSRCs, etc.) More...
guint64	janus_random_uint64 (void)
	Helper to generate random 64-bit unsigned integers (useful for Janus IDs) More...
guint64 *	janus_uint64_dup (guint64 num)
	Helper to generate an allocated copy of a guint64 number. More...
void	janus_flags_reset (janus_flags *flags)
	Janus flags reset method. More...
void	janus_flags_set (janus_flags *flags, uint32_t flag)
	Janus flags set method. More...
void	janus_flags_clear (janus_flags *flags, uint32_t flag)
	Janus flags clear method. More...
gboolean	janus_flags_is_set (janus_flags *flags, uint32_t flag)
	Janus flags check method. More...
char *	janus_string_replace (char *message, const char *old_string, const char *new_string)
	Helper to replace strings. More...
int	janus_mkdir (const char *dir, mode_t mode)
	Helper to create a new directory, and recursively create parent directories if needed. More...
int	janus_get_codec_pt (const char *sdp, const char *codec)
	Ugly and dirty helper to quickly get the payload type associated with a codec in an SDP. More...
const char *	janus_get_codec_from_pt (const char *sdp, int pt)
	Ugly and dirty helper to quickly get the codec associated with a payload type in an SDP. More...
int	janus_pidfile_create (const char *file)
	Create and lock a PID file. More...
int	janus_pidfile_remove (void)
	Unlock and remove a previously created PID file. More...
void	janus_get_json_type_name (int jtype, unsigned int flags, char *type_name)
	Creates a string describing the JSON type and constraint. More...
gboolean	janus_json_is_valid (json_t *val, json_type jtype, unsigned int flags)
	Checks whether the JSON value matches the type and constraint. More...

Detailed Description

Utilities and helpers.

Author

Lorenzo Miniero loren.nosp@m.zo@m.nosp@m.eetec.nosp@m.ho.c.nosp@m.om

Copyright

GNU General Public License v3

Implementations of a few methods that may be of use here and there in the code.

Core

Function Documentation

janus_flags_clear()

void janus_flags_clear	(	janus_flags *	flags,
		uint32_t	flag
	)

Janus flags clear method.

Parameters

[in]	flags	The janus_flags instance to update
[in]	flag	The flag to clear

janus_flags_is_set()

gboolean janus_flags_is_set	(	janus_flags *	flags,
		uint32_t	flag
	)

Janus flags check method.

Parameters

[in]	flags	The janus_flags instance to check
[in]	flag	The flag to check

Returns

true if the flag is set, false otherwise

janus_flags_reset()

void janus_flags_reset

(

janus_flags *

flags

)

Janus flags reset method.

Parameters

[in]

flags

The janus_flags instance to reset

janus_flags_set()

void janus_flags_set	(	janus_flags *	flags,
		uint32_t	flag
	)

Janus flags set method.

Parameters

[in]	flags	The janus_flags instance to update
[in]	flag	The flag to set

janus_get_codec_from_pt()

const char* janus_get_codec_from_pt	(	const char *	sdp,
		int	pt
	)

Ugly and dirty helper to quickly get the codec associated with a payload type in an SDP.

Parameters

sdp	The SDP to parse
pt	The payload type to look for

Returns

The codec name, if found, NULL otherwise

janus_get_codec_pt()

int janus_get_codec_pt	(	const char *	sdp,
		const char *	codec
	)

Ugly and dirty helper to quickly get the payload type associated with a codec in an SDP.

Parameters

sdp	The SDP to parse
codec	The codec to look for

Returns

The payload type, if found, -1 otherwise

janus_get_json_type_name()

void janus_get_json_type_name	(	int	jtype,
		unsigned int	flags,
		char *	type_name
	)

Creates a string describing the JSON type and constraint.

Parameters

	jtype	The JSON type, e.g., JSON_STRING
	flags	Indicates constraints for the described type
[out]	type_name	The type description, e.g., "a positive integer"; required size is 19 characters

Returns

0 if successful, a negative integer otherwise

janus_get_monotonic_time()

gint64 janus_get_monotonic_time

(

void

)

Helper to retrieve the system monotonic time, as Glib's g_get_monotonic_time may not be available (only since 2.28)

Returns

The system monotonic time

janus_get_real_time()

gint64 janus_get_real_time

(

void

)

Helper to retrieve the system real time, as Glib's g_get_real_time may not be available (only since 2.28)

Returns

The system real time

janus_is_true()

gboolean janus_is_true

(

const char *

value

)

Helper to parse yes/no|true/false configuration values.

Parameters

value

The configuration value to parse

Returns

true if the value contains a "yes", "YES", "true", TRUE", "1", false otherwise

janus_json_is_valid()

gboolean janus_json_is_valid	(	json_t *	val,
		json_type	jtype,
		unsigned int	flags
	)

Checks whether the JSON value matches the type and constraint.

Parameters

val	The JSON value to be checked
jtype	The JSON type, e.g., JSON_STRING
flags	Indicates constraints for the described type

Returns

TRUE if the value is valid

janus_mkdir()

int janus_mkdir	(	const char *	dir,
		mode_t	mode
	)

Helper to create a new directory, and recursively create parent directories if needed.

Parameters

dir	Path to the new folder to create
mode	File permissions for the new directory file

Returns

An integer like the regular mkdir does

Note

A failure may indicate that creating any of the subdirectories failed: some may still have been created

janus_pidfile_create()

int janus_pidfile_create

(

const char *

file

)

Create and lock a PID file.

Parameters

file	Path to the PID file to use

Returns

0 if successful, a negative integer otherwise

janus_pidfile_remove()

int janus_pidfile_remove

(

void

)

Unlock and remove a previously created PID file.

Returns

0 if successful, a negative integer otherwise

janus_random_uint32()

guint32 janus_random_uint32

(

void

)

Helper to generate random 32-bit unsigned integers (useful for SSRCs, etc.)

Note

Currently just wraps g_random_int()

Returns

A random 32-bit unsigned integer

janus_random_uint64()

guint64 janus_random_uint64

(

void

)

Helper to generate random 64-bit unsigned integers (useful for Janus IDs)

Returns

A random 64-bit unsigned integer

janus_strcmp_const_time()

gboolean janus_strcmp_const_time	(	const void *	str1,
		const void *	str2
	)

Helper to compare strings in constant time.

Parameters

str1	The first string to compare
str2	The second string to compare

Returns

true if the strings are the same, false otherwise

janus_string_replace()

char* janus_string_replace	(	char *	message,
		const char *	old_string,
		const char *	new_string
	)

Helper to replace strings.

Parameters

message	The string that contains the text to replace, which may be freed if it is too short
old_string	The old text to replace
new_string	The new text

Returns

A pointer to the updated text string (re-allocated or just updated)

janus_uint64_dup()

guint64* janus_uint64_dup

(

guint64

num

)

Helper to generate an allocated copy of a guint64 number.

Note

While apparently silly, this is needed in order to make sure guint64 values used as keys in GHashTable operations are not lost: using temporary guint64 numbers in a g_hash_table_insert, for instance, will cause the key to contain garbage as soon as the temporary variable is lost, and all opererations on the key to fail

Parameters

num	The guint64 number to duplicate

Returns

A pointer to a guint64 number, if successful, NULL otherwise