\hypertarget{group__log}{}\section{Logging}
\label{group__log}\index{Logging@{Logging}}
\subsection*{Enumerations}
\begin{DoxyCompactItemize}
\item 
enum {\bfseries lws\+\_\+log\+\_\+levels} \{ \\*
{\bfseries L\+L\+L\+\_\+\+E\+RR} = 1 $<$$<$ 0, 
{\bfseries L\+L\+L\+\_\+\+W\+A\+RN} = 1 $<$$<$ 1, 
{\bfseries L\+L\+L\+\_\+\+N\+O\+T\+I\+CE} = 1 $<$$<$ 2, 
{\bfseries L\+L\+L\+\_\+\+I\+N\+FO} = 1 $<$$<$ 3, 
\\*
{\bfseries L\+L\+L\+\_\+\+D\+E\+B\+UG} = 1 $<$$<$ 4, 
{\bfseries L\+L\+L\+\_\+\+P\+A\+R\+S\+ER} = 1 $<$$<$ 5, 
{\bfseries L\+L\+L\+\_\+\+H\+E\+A\+D\+ER} = 1 $<$$<$ 6, 
{\bfseries L\+L\+L\+\_\+\+E\+XT} = 1 $<$$<$ 7, 
\\*
{\bfseries L\+L\+L\+\_\+\+C\+L\+I\+E\+NT} = 1 $<$$<$ 8, 
{\bfseries L\+L\+L\+\_\+\+L\+A\+T\+E\+N\+CY} = 1 $<$$<$ 9, 
{\bfseries L\+L\+L\+\_\+\+C\+O\+U\+NT} = 10
 \}\hypertarget{group__log_ga14542b84d2c76efa7814124bb10f9c5f}{}\label{group__log_ga14542b84d2c76efa7814124bb10f9c5f}

\end{DoxyCompactItemize}
\subsection*{Functions}
\begin{DoxyCompactItemize}
\item 
L\+W\+S\+\_\+\+V\+I\+S\+I\+B\+LE L\+W\+S\+\_\+\+E\+X\+T\+E\+RN void {\bfseries \+\_\+lws\+\_\+log} (int filter, const char $\ast$format,...)\hypertarget{group__log_gaf5f07837692b2f231a79da8a058288aa}{}\label{group__log_gaf5f07837692b2f231a79da8a058288aa}

\item 
L\+W\+S\+\_\+\+V\+I\+S\+I\+B\+LE L\+W\+S\+\_\+\+E\+X\+T\+E\+RN void {\bfseries \+\_\+lws\+\_\+logv} (int filter, const char $\ast$format, va\+\_\+list vl)\hypertarget{group__log_ga74eb146969f0595e12ea835851b4588e}{}\label{group__log_ga74eb146969f0595e12ea835851b4588e}

\item 
L\+W\+S\+\_\+\+V\+I\+S\+I\+B\+LE L\+W\+S\+\_\+\+E\+X\+T\+E\+RN int \hyperlink{group__log_ga42e39775c6b69b7251bdbf5a2cdd5dcd}{lwsl\+\_\+timestamp} (int level, char $\ast$p, int len)
\item 
L\+W\+S\+\_\+\+V\+I\+S\+I\+B\+LE L\+W\+S\+\_\+\+E\+X\+T\+E\+RN void \hyperlink{group__log_ga898b1f03872ad019f507d4e35bbefa90}{lwsl\+\_\+hexdump} (void $\ast$buf, size\+\_\+t len)
\item 
L\+W\+S\+\_\+\+V\+I\+S\+I\+B\+LE L\+W\+S\+\_\+\+E\+X\+T\+E\+RN void \hyperlink{group__log_ga244647f9e1bf0097ccdde66d74f41e26}{lws\+\_\+set\+\_\+log\+\_\+level} (int level, void($\ast$log\+\_\+emit\+\_\+function)(int level, const char $\ast$line))
\item 
L\+W\+S\+\_\+\+V\+I\+S\+I\+B\+LE L\+W\+S\+\_\+\+E\+X\+T\+E\+RN void \hyperlink{group__log_gab7c0fc936cc9f1eb58e2bb234c15147c}{lwsl\+\_\+emit\+\_\+syslog} (int level, const char $\ast$line)
\end{DoxyCompactItemize}


\subsection{Detailed Description}
\subsubsection*{Logging}

Lws provides flexible and filterable logging facilities, which can be used inside lws and in user code.

Log categories may be individually filtered bitwise, and directed to built-\/in sinks for syslog-\/compatible logging, or a user-\/defined function. 

\subsection{Function Documentation}
\index{Logging@{Logging}!lws\+\_\+set\+\_\+log\+\_\+level@{lws\+\_\+set\+\_\+log\+\_\+level}}
\index{lws\+\_\+set\+\_\+log\+\_\+level@{lws\+\_\+set\+\_\+log\+\_\+level}!Logging@{Logging}}
\subsubsection[{\texorpdfstring{lws\+\_\+set\+\_\+log\+\_\+level(int level, void($\ast$log\+\_\+emit\+\_\+function)(int level, const char $\ast$line))}{lws\_set\_log\_level(int level, void(*log\_emit\_function)(int level, const char *line))}}]{\setlength{\rightskip}{0pt plus 5cm}L\+W\+S\+\_\+\+V\+I\+S\+I\+B\+LE L\+W\+S\+\_\+\+E\+X\+T\+E\+RN void lws\+\_\+set\+\_\+log\+\_\+level (
\begin{DoxyParamCaption}
\item[{int}]{level, }
\item[{void($\ast$)(int level, const char $\ast$line)}]{log\+\_\+emit\+\_\+function}
\end{DoxyParamCaption}
)}\hypertarget{group__log_ga244647f9e1bf0097ccdde66d74f41e26}{}\label{group__log_ga244647f9e1bf0097ccdde66d74f41e26}


{\ttfamily \#include $<$\hyperlink{libwebsockets_8h}{lib/libwebsockets.\+h}$>$}

\hyperlink{group__log_ga244647f9e1bf0097ccdde66d74f41e26}{lws\+\_\+set\+\_\+log\+\_\+level()} -\/ Set the logging bitfield 
\begin{DoxyParams}{Parameters}
{\em level} & OR together the L\+L\+L\+\_\+ debug contexts you want output from \\
\hline
{\em log\+\_\+emit\+\_\+function} & N\+U\+LL to leave it as it is, or a user-\/supplied function to perform log string emission instead of the default stderr one.\\
\hline
\end{DoxyParams}
log level defaults to \char`\"{}err\char`\"{}, \char`\"{}warn\char`\"{} and \char`\"{}notice\char`\"{} contexts enabled and emission on stderr. \index{Logging@{Logging}!lwsl\+\_\+emit\+\_\+syslog@{lwsl\+\_\+emit\+\_\+syslog}}
\index{lwsl\+\_\+emit\+\_\+syslog@{lwsl\+\_\+emit\+\_\+syslog}!Logging@{Logging}}
\subsubsection[{\texorpdfstring{lwsl\+\_\+emit\+\_\+syslog(int level, const char $\ast$line)}{lwsl\_emit\_syslog(int level, const char *line)}}]{\setlength{\rightskip}{0pt plus 5cm}L\+W\+S\+\_\+\+V\+I\+S\+I\+B\+LE L\+W\+S\+\_\+\+E\+X\+T\+E\+RN void lwsl\+\_\+emit\+\_\+syslog (
\begin{DoxyParamCaption}
\item[{int}]{level, }
\item[{const char $\ast$}]{line}
\end{DoxyParamCaption}
)}\hypertarget{group__log_gab7c0fc936cc9f1eb58e2bb234c15147c}{}\label{group__log_gab7c0fc936cc9f1eb58e2bb234c15147c}


{\ttfamily \#include $<$\hyperlink{libwebsockets_8h}{lib/libwebsockets.\+h}$>$}

\hyperlink{group__log_gab7c0fc936cc9f1eb58e2bb234c15147c}{lwsl\+\_\+emit\+\_\+syslog()} -\/ helper log emit function writes to system log


\begin{DoxyParams}{Parameters}
{\em level} & one of L\+L\+L\+\_\+ log level indexes \\
\hline
{\em line} & log string\\
\hline
\end{DoxyParams}
You use this by passing the function pointer to \hyperlink{group__log_ga244647f9e1bf0097ccdde66d74f41e26}{lws\+\_\+set\+\_\+log\+\_\+level()}, to set it as the log emit function, it is not called directly. \index{Logging@{Logging}!lwsl\+\_\+hexdump@{lwsl\+\_\+hexdump}}
\index{lwsl\+\_\+hexdump@{lwsl\+\_\+hexdump}!Logging@{Logging}}
\subsubsection[{\texorpdfstring{lwsl\+\_\+hexdump(void $\ast$buf, size\+\_\+t len)}{lwsl\_hexdump(void *buf, size\_t len)}}]{\setlength{\rightskip}{0pt plus 5cm}L\+W\+S\+\_\+\+V\+I\+S\+I\+B\+LE L\+W\+S\+\_\+\+E\+X\+T\+E\+RN void lwsl\+\_\+hexdump (
\begin{DoxyParamCaption}
\item[{void $\ast$}]{buf, }
\item[{size\+\_\+t}]{len}
\end{DoxyParamCaption}
)}\hypertarget{group__log_ga898b1f03872ad019f507d4e35bbefa90}{}\label{group__log_ga898b1f03872ad019f507d4e35bbefa90}


{\ttfamily \#include $<$\hyperlink{libwebsockets_8h}{lib/libwebsockets.\+h}$>$}

\hyperlink{group__log_ga898b1f03872ad019f507d4e35bbefa90}{lwsl\+\_\+hexdump()} -\/ helper to hexdump a buffer (D\+E\+B\+UG builds only)


\begin{DoxyParams}{Parameters}
{\em buf} & buffer start to dump \\
\hline
{\em len} & length of buffer to dump \\
\hline
\end{DoxyParams}
\index{Logging@{Logging}!lwsl\+\_\+timestamp@{lwsl\+\_\+timestamp}}
\index{lwsl\+\_\+timestamp@{lwsl\+\_\+timestamp}!Logging@{Logging}}
\subsubsection[{\texorpdfstring{lwsl\+\_\+timestamp(int level, char $\ast$p, int len)}{lwsl\_timestamp(int level, char *p, int len)}}]{\setlength{\rightskip}{0pt plus 5cm}L\+W\+S\+\_\+\+V\+I\+S\+I\+B\+LE L\+W\+S\+\_\+\+E\+X\+T\+E\+RN int lwsl\+\_\+timestamp (
\begin{DoxyParamCaption}
\item[{int}]{level, }
\item[{char $\ast$}]{p, }
\item[{int}]{len}
\end{DoxyParamCaption}
)}\hypertarget{group__log_ga42e39775c6b69b7251bdbf5a2cdd5dcd}{}\label{group__log_ga42e39775c6b69b7251bdbf5a2cdd5dcd}


{\ttfamily \#include $<$\hyperlink{libwebsockets_8h}{lib/libwebsockets.\+h}$>$}

lwsl\+\_\+timestamp\+: generate logging timestamp string


\begin{DoxyParams}{Parameters}
{\em level} & logging level \\
\hline
{\em p} & char $\ast$ buffer to take timestamp \\
\hline
{\em len} & length of p\\
\hline
\end{DoxyParams}
returns length written in p