Qsmtp  0.23svn
Defines | Functions | Variables
lib/netio.c File Reference

functions for network I/O More...

#include <sys/select.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <assert.h>
#include "netio.h"
#include "log.h"
#include "ssl_timeoutio.h"
#include "tls.h"

Defines

#define DEBUG_IN(l)   {}
#define DEBUG_OUT(s, l)   {}

Functions

int net_read (void)
int netwrite (const char *s)
int netnwrite (const char *s, const size_t l)
int net_writen (const char *const *s)
int net_write_multiline (const char *const *s)
size_t net_readbin (size_t num, char *buf)
size_t net_readline (size_t num, char *buf)
int data_pending (void)

Variables

char linein [1002]
size_t linelen
time_t timeout

Detailed Description

functions for network I/O


Function Documentation

int data_pending ( void  )

check if there is data ready to be read without blocking

Return values:
0if no data
1if data
-1on error
int net_read ( void  )

read one line from the network

Return values:
0on success
-1on error (errno is set)

does not return on timeout, programm will be cancelled

size_t net_readbin ( size_t  num,
char *  buf 
)

read a given number of bytes from network as binary data (i.e. without any mangling)

Parameters:
numnumber of bytes to read
bufbuffer to store data (must have enough space for (num + 1) bytes)
Returns:
number of bytes read
Return values:
-1on error
size_t net_readline ( size_t  num,
char *  buf 
)

read up to a given number of bytes from network but stop at the first CRLF

Parameters:
numnumber of bytes to read, must be < 1002 so everything behind the CRLF can be copied back to lineinn
bufbuffer to store data (must have enough space)
Returns:
number of bytes read
Return values:
-1on error

The trailing CRLF sequence is kept in the buffer. This function will return an error if it detects a bare CR or LF in the middle of the input data, but it cannot detect if the CR goes in one call and LF in the next, so it will allow the output to be just LF or to end in CR.

int net_write_multiline ( const char *const *  s)

write multiple lines to the network

Parameters:
sarray of strings to send
Return values:
0on success
-1on error (errno is set)

This combines all given strings into one buffer and send them out to the network. This allows the underlying network stack to use the least sensible number of packets, reducing network latency. If memory allocation fails for the intermediate buffer the lines may be send in smaller chunks, which is less efficient but is no other loss in functionality.

Does not return on timeout, programm will be cancelled.

If one part or multiple consecutive parts covers a whole SMTP line this line must conform to the SMTP line length limit (512 bytes).

int net_writen ( const char *const *  s)

write one line to the network, fold if needed

Parameters:
sarray of strings to send
Return values:
0on success
-1on error (errno is set)

does not return on timeout, programm will be cancelled

Warning:
s[0] must be short enough to fit completely into the buffer
every s[] must not have a sequence longer then 506 characters without a space (' ') in them
int netnwrite ( const char *  s,
const size_t  l 
)

write one line to the network

Parameters:
sline to be written (nothing else it written so it should contain CRLF)
llength of s
Return values:
0on success
-1on error (errno is set)

does not return on timeout, programm will be cancelled

int netwrite ( const char *  s)

write one line to the network

Parameters:
sline to be written (nothing else it written so it should contain CRLF)
Return values:
0on success
-1on error (errno is set)

-does not return on timeout, programm will be cancelled -same as net_write but expects that line is <= 512 characters and includes CRLF


Variable Documentation

char linein[1002]

buffer for the line to read: max 1000 chars including CRLF, leading extra '.', closing '\0'

size_t linelen

length of the line

time_t timeout

how long to wait for data