solanum-vs-hackint-and-char.../libcharybdis/linebuf.c
nenolod 212380e3f4 [svn] - the new plan:
+ branches/release-2.1 -> 2.2 base
  + 3.0 -> branches/cxxconversion
  + backport some immediate 3.0 functionality for 2.2
  + other stuff
2007-01-24 22:40:21 -08:00

686 lines
15 KiB
C

/*
* ircd-ratbox: A slightly useful ircd.
* linebuf.c: Maintains linebuffers.
*
* Copyright (C) 2001-2002 Adrian Chadd <adrian@creative.net.au>
* Copyright (C) 2002 Hybrid Development Team
* Copyright (C) 2002-2005 ircd-ratbox development team
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
* USA
*
* $Id: linebuf.c 1110 2006-03-29 22:55:25Z nenolod $
*/
#include "stdinc.h"
#include "tools.h"
#include "client.h"
#include "linebuf.h"
#include "memory.h"
#include "event.h"
#include "balloc.h"
#include "hook.h"
#include "commio.h"
#include "sprintf_irc.h"
#ifdef STRING_WITH_STRINGS
# include <string.h>
# include <strings.h>
#else
# ifdef HAVE_STRING_H
# include <string.h>
# else
# ifdef HAVE_STRINGS_H
# include <strings.h>
# endif
# endif
#endif
extern BlockHeap *linebuf_heap;
static int bufline_count = 0;
/*
* linebuf_init
*
* Initialise the linebuf mechanism
*/
void
linebuf_init(void)
{
linebuf_heap = BlockHeapCreate(sizeof(buf_line_t), LINEBUF_HEAP_SIZE);
}
static buf_line_t *
linebuf_allocate(void)
{
buf_line_t *t;
t = BlockHeapAlloc(linebuf_heap);
t->refcount = 0;
return (t);
}
static void
linebuf_free(buf_line_t * p)
{
BlockHeapFree(linebuf_heap, p);
}
/*
* linebuf_new_line
*
* Create a new line, and link it to the given linebuf.
* It will be initially empty.
*/
static buf_line_t *
linebuf_new_line(buf_head_t * bufhead)
{
buf_line_t *bufline;
dlink_node *node;
bufline = linebuf_allocate();
if(bufline == NULL)
return NULL;
++bufline_count;
node = make_dlink_node();
bufline->len = 0;
bufline->terminated = 0;
bufline->flushing = 0;
bufline->raw = 0;
/* Stick it at the end of the buf list */
dlinkAddTail(bufline, node, &bufhead->list);
bufline->refcount++;
/* And finally, update the allocated size */
bufhead->alloclen++;
bufhead->numlines++;
return bufline;
}
/*
* linebuf_done_line
*
* We've finished with the given line, so deallocate it
*/
static void
linebuf_done_line(buf_head_t * bufhead, buf_line_t * bufline, dlink_node * node)
{
/* Remove it from the linked list */
dlinkDestroy(node, &bufhead->list);
/* Update the allocated size */
bufhead->alloclen--;
bufhead->len -= bufline->len;
s_assert(bufhead->len >= 0);
bufhead->numlines--;
bufline->refcount--;
s_assert(bufline->refcount >= 0);
if(bufline->refcount == 0)
{
/* and finally, deallocate the buf */
--bufline_count;
s_assert(bufline_count >= 0);
linebuf_free(bufline);
}
}
/*
* skip to end of line or the crlfs, return the number of bytes ..
*/
static inline int
linebuf_skip_crlf(char *ch, int len)
{
int orig_len = len;
/* First, skip until the first non-CRLF */
for (; len; len--, ch++)
{
if(*ch == '\r')
break;
else if(*ch == '\n')
break;
}
/* Then, skip until the last CRLF */
for (; len; len--, ch++)
{
if((*ch != '\r') && (*ch != '\n'))
break;
}
s_assert(orig_len > len);
return (orig_len - len);
}
/*
* linebuf_newbuf
*
* Initialise the new buffer
*/
void
linebuf_newbuf(buf_head_t * bufhead)
{
/* not much to do right now :) */
memset(bufhead, 0, sizeof(buf_head_t));
}
/*
* client_flush_input
*
* inputs - pointer to client
* output - none
* side effects - all input line bufs are flushed
*/
void
client_flush_input(struct Client *client_p)
{
/* This way, it can be called for remote client as well */
if(client_p->localClient == NULL)
return;
linebuf_donebuf(&client_p->localClient->buf_recvq);
}
/*
* linebuf_donebuf
*
* Flush all the lines associated with this buffer
*/
void
linebuf_donebuf(buf_head_t * bufhead)
{
while (bufhead->list.head != NULL)
{
linebuf_done_line(bufhead,
(buf_line_t *) bufhead->list.head->data, bufhead->list.head);
}
}
/*
* linebuf_copy_line
*
* Okay..this functions comments made absolutely no sense.
*
* Basically what we do is this. Find the first chunk of text
* and then scan for a CRLF. If we didn't find it, but we didn't
* overflow our buffer..we wait for some more data.
* If we found a CRLF, we replace them with a \0 character.
* If we overflowed, we copy the most our buffer can handle, terminate
* it with a \0 and return.
*
* The return value is the amount of data we consumed. This could
* be different than the size of the linebuffer, as when we discard
* the overflow, we don't want to process it again.
*
* This still sucks in my opinion, but it seems to work.
*
* -Aaron
*/
static int
linebuf_copy_line(buf_head_t * bufhead, buf_line_t * bufline, char *data, int len)
{
int cpylen = 0; /* how many bytes we've copied */
char *ch = data; /* Pointer to where we are in the read data */
char *bufch = bufline->buf + bufline->len;
int clen = 0; /* how many bytes we've processed,
and don't ever want to see again.. */
/* If its full or terminated, ignore it */
bufline->raw = 0;
s_assert(bufline->len < BUF_DATA_SIZE);
if(bufline->terminated == 1)
return 0;
clen = cpylen = linebuf_skip_crlf(ch, len);
if(clen == -1)
return -1;
/* This is the ~overflow case..This doesn't happen often.. */
if(cpylen > (BUF_DATA_SIZE - bufline->len - 1))
{
memcpy(bufch, ch, (BUF_DATA_SIZE - bufline->len - 1));
bufline->buf[BUF_DATA_SIZE - 1] = '\0';
bufch = bufline->buf + BUF_DATA_SIZE - 2;
while (cpylen && (*bufch == '\r' || *bufch == '\n'))
{
*bufch = '\0';
cpylen--;
bufch--;
}
bufline->terminated = 1;
bufline->len = BUF_DATA_SIZE - 1;
bufhead->len += BUF_DATA_SIZE - 1;
return clen;
}
memcpy(bufch, ch, cpylen);
bufch += cpylen;
*bufch = '\0';
bufch--;
if(*bufch != '\r' && *bufch != '\n')
{
/* No linefeed, bail for the next time */
bufhead->len += cpylen;
bufline->len += cpylen;
bufline->terminated = 0;
return clen;
}
/* Yank the CRLF off this, replace with a \0 */
while (cpylen && (*bufch == '\r' || *bufch == '\n'))
{
*bufch = '\0';
cpylen--;
bufch--;
}
bufline->terminated = 1;
bufhead->len += cpylen;
bufline->len += cpylen;
return clen;
}
/*
* linebuf_copy_raw
*
* Copy as much data as possible directly into a linebuf,
* splitting at \r\n, but without altering any data.
*
*/
static int
linebuf_copy_raw(buf_head_t * bufhead, buf_line_t * bufline, char *data, int len)
{
int cpylen = 0; /* how many bytes we've copied */
char *ch = data; /* Pointer to where we are in the read data */
char *bufch = bufline->buf + bufline->len;
int clen = 0; /* how many bytes we've processed,
and don't ever want to see again.. */
/* If its full or terminated, ignore it */
bufline->raw = 1;
s_assert(bufline->len < BUF_DATA_SIZE);
if(bufline->terminated == 1)
return 0;
clen = cpylen = linebuf_skip_crlf(ch, len);
if(clen == -1)
return -1;
/* This is the overflow case..This doesn't happen often.. */
if(cpylen > (BUF_DATA_SIZE - bufline->len - 1))
{
clen = BUF_DATA_SIZE - bufline->len - 1;
memcpy(bufch, ch, clen);
bufline->buf[BUF_DATA_SIZE - 1] = '\0';
bufch = bufline->buf + BUF_DATA_SIZE - 2;
bufline->terminated = 1;
bufline->len = BUF_DATA_SIZE - 1;
bufhead->len += BUF_DATA_SIZE - 1;
return clen;
}
memcpy(bufch, ch, cpylen);
bufch += cpylen;
*bufch = '\0';
bufch--;
if(*bufch != '\r' && *bufch != '\n')
{
/* No linefeed, bail for the next time */
bufhead->len += cpylen;
bufline->len += cpylen;
bufline->terminated = 0;
return clen;
}
bufline->terminated = 1;
bufhead->len += cpylen;
bufline->len += cpylen;
return clen;
}
/*
* linebuf_parse
*
* Take a given buffer and break out as many buffers as we can.
* If we find a CRLF, we terminate that buffer and create a new one.
* If we don't find a CRLF whilst parsing a buffer, we don't mark it
* 'finished', so the next loop through we can continue appending ..
*
* A few notes here, which you'll need to understand before continuing.
*
* - right now I'm only dealing with single sized buffers. Later on,
* I might consider chaining buffers together to get longer "lines"
* but seriously, I don't see the advantage right now.
*
* - This *is* designed to turn into a reference-counter-protected setup
* to dodge copious copies.
*/
int
linebuf_parse(buf_head_t * bufhead, char *data, int len, int raw)
{
buf_line_t *bufline;
int cpylen;
int linecnt = 0;
/* First, if we have a partial buffer, try to squeze data into it */
if(bufhead->list.tail != NULL)
{
/* Check we're doing the partial buffer thing */
bufline = bufhead->list.tail->data;
s_assert(!bufline->flushing);
/* just try, the worst it could do is *reject* us .. */
if(!raw)
cpylen = linebuf_copy_line(bufhead, bufline, data, len);
else
cpylen = linebuf_copy_raw(bufhead, bufline, data, len);
if(cpylen == -1)
return -1;
linecnt++;
/* If we've copied the same as what we've got, quit now */
if(cpylen == len)
return linecnt; /* all the data done so soon? */
/* Skip the data and update len .. */
len -= cpylen;
s_assert(len >= 0);
data += cpylen;
}
/* Next, the loop */
while (len > 0)
{
/* We obviously need a new buffer, so .. */
bufline = linebuf_new_line(bufhead);
/* And parse */
if(!raw)
cpylen = linebuf_copy_line(bufhead, bufline, data, len);
else
cpylen = linebuf_copy_raw(bufhead, bufline, data, len);
if(cpylen == -1)
return -1;
len -= cpylen;
s_assert(len >= 0);
data += cpylen;
linecnt++;
}
return linecnt;
}
/*
* linebuf_get
*
* get the next buffer from our line. For the time being it will copy
* data into the given buffer and free the underlying linebuf.
*/
int
linebuf_get(buf_head_t * bufhead, char *buf, int buflen, int partial, int raw)
{
buf_line_t *bufline;
int cpylen;
char *start, *ch;
/* make sure we have a line */
if(bufhead->list.head == NULL)
return 0; /* Obviously not.. hrm. */
bufline = bufhead->list.head->data;
/* make sure that the buffer was actually *terminated */
if(!(partial || bufline->terminated))
return 0; /* Wait for more data! */
/* make sure we've got the space, including the NULL */
cpylen = bufline->len;
s_assert(cpylen + 1 <= buflen);
/* Copy it */
start = bufline->buf;
/* if we left extraneous '\r\n' characters in the string,
* and we don't want to read the raw data, clean up the string.
*/
if(bufline->raw && !raw)
{
/* skip leading EOL characters */
while (cpylen && (*start == '\r' || *start == '\n'))
{
start++;
cpylen--;
}
/* skip trailing EOL characters */
ch = &start[cpylen - 1];
while (cpylen && (*ch == '\r' || *ch == '\n'))
{
ch--;
cpylen--;
}
}
memcpy(buf, start, cpylen + 1);
/* convert CR/LF to NULL */
if(bufline->raw && !raw)
buf[cpylen] = '\0';
s_assert(cpylen >= 0);
/* Deallocate the line */
linebuf_done_line(bufhead, bufline, bufhead->list.head);
/* return how much we copied */
return cpylen;
}
/*
* linebuf_attach
*
* attach the lines in a buf_head_t to another buf_head_t
* without copying the data (using refcounts).
*/
void
linebuf_attach(buf_head_t * bufhead, buf_head_t * new)
{
dlink_node *ptr;
buf_line_t *line;
DLINK_FOREACH(ptr, new->list.head)
{
line = ptr->data;
dlinkAddTailAlloc(line, &bufhead->list);
/* Update the allocated size */
bufhead->alloclen++;
bufhead->len += line->len;
bufhead->numlines++;
line->refcount++;
}
}
/*
* linebuf_putmsg
*
* Similar to linebuf_put, but designed for use by send.c.
*
* prefixfmt is used as a format for the varargs, and is inserted first.
* Then format/va_args is appended to the buffer.
*/
void
linebuf_putmsg(buf_head_t * bufhead, const char *format, va_list * va_args,
const char *prefixfmt, ...)
{
buf_line_t *bufline;
int len = 0;
va_list prefix_args;
/* make sure the previous line is terminated */
#ifndef NDEBUG
if(bufhead->list.tail)
{
bufline = bufhead->list.tail->data;
s_assert(bufline->terminated);
}
#endif
/* Create a new line */
bufline = linebuf_new_line(bufhead);
if(prefixfmt != NULL)
{
va_start(prefix_args, prefixfmt);
len = ircvsnprintf(bufline->buf, BUF_DATA_SIZE, prefixfmt, prefix_args);
va_end(prefix_args);
}
if(va_args != NULL)
{
len += ircvsnprintf((bufline->buf + len), (BUF_DATA_SIZE - len), format, *va_args);
}
bufline->terminated = 1;
/* Truncate the data if required */
if(len > 510)
{
len = 510;
bufline->buf[len++] = '\r';
bufline->buf[len++] = '\n';
}
else if(len == 0)
{
bufline->buf[len++] = '\r';
bufline->buf[len++] = '\n';
bufline->buf[len] = '\0';
}
else
{
/* Chop trailing CRLF's .. */
while ((bufline->buf[len] == '\r')
|| (bufline->buf[len] == '\n') || (bufline->buf[len] == '\0'))
{
len--;
}
bufline->buf[++len] = '\r';
bufline->buf[++len] = '\n';
bufline->buf[++len] = '\0';
}
bufline->len = len;
bufhead->len += len;
}
/*
* linebuf_flush
*
* Flush data to the buffer. It tries to write as much data as possible
* to the given socket. Any return values are passed straight through.
* If there is no data in the socket, EWOULDBLOCK is set as an errno
* rather than returning 0 (which would map to an EOF..)
*
* Notes: XXX We *should* have a clue here when a non-full buffer is arrived.
* and tag it so that we don't re-schedule another write until
* we have a CRLF.
*/
int
linebuf_flush(int fd, buf_head_t * bufhead)
{
buf_line_t *bufline;
int retval;
/* Check we actually have a first buffer */
if(bufhead->list.head == NULL)
{
/* nope, so we return none .. */
errno = EWOULDBLOCK;
return -1;
}
bufline = bufhead->list.head->data;
/* And that its actually full .. */
if(!bufline->terminated)
{
errno = EWOULDBLOCK;
return -1;
}
/* Check we're flushing the first buffer */
if(!bufline->flushing)
{
bufline->flushing = 1;
bufhead->writeofs = 0;
}
/* Now, try writing data */
retval = send(fd, bufline->buf + bufhead->writeofs, bufline->len - bufhead->writeofs, 0);
if(retval <= 0)
return retval;
/* we've got data, so update the write offset */
bufhead->writeofs += retval;
/* if we've written everything *and* the CRLF, deallocate and update
bufhead */
if(bufhead->writeofs == bufline->len)
{
bufhead->writeofs = 0;
s_assert(bufhead->len >= 0);
linebuf_done_line(bufhead, bufline, bufhead->list.head);
}
/* Return line length */
return retval;
}
/*
* count linebufs for stats z
*/
void
count_linebuf_memory(size_t * count, size_t * linebuf_memory_used)
{
BlockHeapUsage(linebuf_heap, count, NULL, linebuf_memory_used);
}