ossp-pkg/l2/l2_ch_prefix.c
1.9
/*
** L2 - OSSP Logging Library
** Copyright (c) 2001 The OSSP Project (http://www.ossp.org/)
** Copyright (c) 2001 Cable & Wireless Deutschland (http://www.cw.com/de/)
**
** This file is part of OSSP L2, a flexible logging library which
** can be found at http://www.ossp.org/pkg/l2/.
**
** Permission to use, copy, modify, and distribute this software for
** any purpose with or without fee is hereby granted, provided that
** the above copyright notice and this permission notice appear in all
** copies.
**
** THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
** WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
** MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
** IN NO EVENT SHALL THE AUTHORS AND COPYRIGHT HOLDERS AND THEIR
** CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
** USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
** ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
** OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
** OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
** SUCH DAMAGE.
**
** l2_ch_prefix.c: prefixing channel implementation
*/
#include <time.h>
#include "l2.h"
/* declare private channel configuration */
typedef struct {
char *timefmt;
char *timezone;
char timebuf[1024];
} l2_ch_prefix_t;
/* create channel */
static l2_result_t hook_create(l2_context_t *ctx, l2_channel_t *ch)
{
l2_ch_prefix_t *cfg;
/* allocate private channel configuration */
if ((cfg = (l2_ch_prefix_t *)malloc(sizeof(l2_ch_prefix_t))) == NULL)
return L2_ERR_MEM;
/* initialize configuration with reasonable defaults */
cfg->timefmt = NULL;
cfg->timezone = strdup("local");
/* link private channel configuration into channel context */
ctx->vp = cfg;
return L2_OK;
}
/* configure channel */
static l2_result_t hook_configure(l2_context_t *ctx, l2_channel_t *ch, const char *fmt, va_list ap)
{
l2_ch_prefix_t *cfg = (l2_ch_prefix_t *)ctx->vp;
l2_param_t pa[3];
l2_result_t rv;
/* feed and call generic parameter parsing engine */
L2_PARAM_SET(pa[0], timefmt, STRING, &cfg->timefmt);
L2_PARAM_SET(pa[1], timezone, STRING, &cfg->timezone);
L2_PARAM_END(pa[2]);
rv = l2_util_setparams(pa, fmt, ap);
/* argument consistency check */
if (rv == L2_OK) {
if (cfg->timezone == NULL)
return L2_ERR_ARG;
if (!( strcmp(cfg->timezone, "local") == 0
|| strcmp(cfg->timezone, "utc") == 0))
return L2_ERR_ARG;
}
return rv;
}
/* write to channel */
static l2_result_t hook_write(l2_context_t *ctx, l2_channel_t *ch,
const char *buf, size_t buf_size)
{
l2_ch_prefix_t *cfg;
l2_channel_t *downstream;
time_t t;
struct tm *tm;
size_t n;
l2_result_t rv;
/* get environment */
cfg = (l2_ch_prefix_t *)ctx->vp;
downstream = l2_channel_downstream(ch);
/* optionally provide prefix */
if (cfg->timefmt != NULL) {
t = time(NULL);
if (strcmp(cfg->timezone, "local") == 0)
tm = localtime(&t);
else if (strcmp(cfg->timezone, "utc") == 0)
tm = gmtime(&t);
else
return L2_ERR_ARG;
if ((n = strftime(cfg->timebuf, sizeof(cfg->timebuf), cfg->timefmt, tm)) == 0)
return L2_ERR_SYS;
if ((rv = l2_channel_write(downstream, cfg->timebuf, n)) != L2_OK)
return rv;
}
/* write to downstream channel */
if ((rv = l2_channel_write(downstream, buf, buf_size)) != L2_OK)
return rv;
return L2_OK;
}
/* destroy channel */
static l2_result_t hook_destroy(l2_context_t *ctx, l2_channel_t *ch)
{
l2_ch_prefix_t *cfg = (l2_ch_prefix_t *)ctx->vp;
if (cfg->timefmt != NULL)
free(cfg->timefmt);
if (cfg->timezone != NULL)
free(cfg->timezone);
free(cfg);
ctx->vp = NULL;
return L2_OK;
}
/* exported channel handler structure */
l2_handler_t l2_handler_prefix = {
L2_CHANNEL_FILTER,
hook_create,
hook_configure,
NULL,
hook_write,
NULL,
NULL,
hook_destroy
};