/*
* atheme-services: A collection of minimalist IRC services
* confparse.c: Initialization and startup of the services system
*
* Copyright (c) 2005-2007 Atheme Project (http://www.atheme.org)
*
* Permission to use, copy, modify, and/or 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 BY THE AUTHOR ``AS IS'' AND ANY EXPRESS 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 AUTHOR 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.
*/
/*
* Description of config files parsed by this:
*
* configfile = *WS *configentry
* configentry = value [1*WS value] [1*WS "{" *(configentry 1*WS) "}" ] *WS ";"
* value = 1*achar / DQUOTE *qchar DQUOTE
* achar = <any CHAR except WS or DQUOTE>
* qchar = <any CHAR except DQUOTE or \> / "\\" / "\" DQUOTE
* comment = "/" "*" <anything except * /> "*" "/" /
* "#" *CHAR %0x0A /
* "//" *CHAR %0x0A
* WS = %x09 / %x0A / %x0D / SPACE / "=" / comment
*
* A value of "include" for toplevel configentries causes a file to be
* included. The included file is logically appended to the current file,
* no matter where the include directive is. Include files must have balanced
* braces.
*/
/*
* Original idea from the csircd config parser written by Fred Jacobs
* and Chris Behrens.
*/
#include "atheme.h"
#include <sys/stat.h>
#include <limits.h>
#define MAX_INCLUDE_NESTING 16
static config_file_t *config_parse(const char *filename, char *confdata);
static void config_entry_free(config_entry_t *ceptr);
static config_file_t *config_load_internal(config_file_t *parent, const char *filename);
#define CF_ERRORED(cf) ((cf)->cf_curline <= 0)
static void config_error(config_file_t *cf, const char *format, ...)
{
va_list ap;
char buffer[1024];
char *ptr;
va_start(ap, format);
vsnprintf(buffer, 1024, format, ap);
va_end(ap);
if ((ptr = strchr(buffer, '\n')) != NULL)
*ptr = '\0';
if (cf != NULL)
{
if (cf->cf_curline < 0)
cf->cf_curline = -cf->cf_curline;
slog(LG_ERROR, "%s:%d: %s",
cf->cf_filename, cf->cf_curline, buffer);
/* mark config parse as failed */
cf->cf_curline = -cf->cf_curline;
}
else
slog(LG_ERROR, "config_parse(): %s",
buffer);
}
static void skip_ws(char ** restrict pos, config_file_t * restrict cf)
{
int startline;
for (;;)
{
switch (**pos)
{
case ' ':
case '\t':
case '\r':
case '=': /* XXX */
break;
case '\n':
cf->cf_curline++;
break;
case '/':
if ((*pos)[1] == '*')
{
startline = cf->cf_curline;
(*pos)++;
(*pos)++;
while (**pos != '\0' && (**pos != '*' || (*pos)[1] != '/'))
{
if (**pos == '\n')
cf->cf_curline++;
(*pos)++;
}
if (**pos == '\0')
config_error(cf, "File ends inside comment starting at line %d", startline);
else
(*pos)++; /* skip '*' */
}
else if ((*pos)[1] == '/')
{
while (**pos != '\0' && **pos != '\n' && **pos != '\r')
(*pos)++;
continue;
}
else
return;
break;
case '#':
while (**pos != '\0' && **pos != '\n' && **pos != '\r')
(*pos)++;
continue;
default:
return;
}
if (**pos == '\0')
return;
(*pos)++;
}
}
static char *get_value(char **pos, config_file_t *cf, char * restrict skipped)
{
char *p = *pos;
char *q;
char *start;
*skipped = '\0';
if (*p == '"')
{
p++;
start = p;
q = p;
while (*p != '\0' && *p != '\r' && *p != '\n' && *p != '"')
{
if (*p == '\\' && (p[1] == '"' || p[1] == '\\'))
p++;
*q++ = *p++;
}
if (*p == '\0')
{
config_error(cf, "File ends inside quoted string");
return NULL;
}
if (*p == '\r' || *p == '\n')
{
config_error(cf, "Newline inside quoted string");
return NULL;
}
if (*p != '"')
{
config_error(cf, "Weird character terminating quoted string (BUG)");
return NULL;
}
p++;
*q = '\0';
*pos = p;
skip_ws(pos, cf);
return start;
}
else
{
start = p;
while (*p != '\0' && *p != '\t' && *p != '\r' && *p != '\n' &&
*p != ' ' && *p != '/' && *p != '#' &&
*p != ';' && *p != '{' && *p != '}')
p++;
if (p == start)
return NULL;
*pos = p;
skip_ws(pos, cf);
if (p == *pos)
*skipped = *p;
*p = '\0';
if (p == *pos)
(*pos)++;
return start;
}
}
static config_file_t *config_parse(const char *filename, char *confdata)
{
config_file_t *cf, *subcf, *lastcf;
config_entry_t **pprevce, *ce, *upce;
char *p, *val;
char c;
cf = smalloc(sizeof *cf);
cf->cf_filename = sstrdup(filename);
cf->cf_curline = 1;
cf->cf_mem = confdata;
lastcf = cf;
pprevce = &cf->cf_entries;
upce = NULL;
p = confdata;
while (*p != '\0')
{
skip_ws(&p, cf);
if (*p == '\0' || CF_ERRORED(cf))
break;
if (*p == '}')
{
if (upce == NULL)
{
config_error(cf, "Extraneous closing brace");
break;
}
ce = upce;
ce->ce_sectlinenum = cf->cf_curline;
pprevce = &ce->ce_next;
upce = ce->ce_prevlevel;
p++;
skip_ws(&p, cf);
if (CF_ERRORED(cf))
break;
if (*p != ';')
{
config_error(cf, "Missing semicolon after closing brace for section ending at line %d", ce->ce_sectlinenum);
break;
}
ce = NULL;
p++;
continue;
}
val = get_value(&p, cf, &c);
if (CF_ERRORED(cf))
break;
if (val == NULL)
{
config_error(cf, "Unexpected character trying to read variable name");
break;
}
ce = smalloc(sizeof *ce);
ce->ce_fileptr = cf;
ce->ce_varlinenum = cf->cf_curline;
ce->ce_varname = val;
ce->ce_prevlevel = upce;
*pprevce = ce;
pprevce = &ce->ce_next;
if (c == '\0' && (*p == '{' || *p == ';'))
c = *p++;
if (c == '{')
{
pprevce = &ce->ce_entries;
upce = ce;
ce = NULL;
}
else if (c == ';')
{
ce = NULL;
}
else if (c != '\0')
{
config_error(cf, "Unexpected characters after unquoted string %s", ce->ce_varname);
break;
}
else
{
val = get_value(&p, cf, &c);
if (CF_ERRORED(cf))
break;
if (val == NULL)
{
config_error(cf, "Unexpected character trying to read value for %s", ce->ce_varname);
break;
}
ce->ce_vardata = val;
if (c == '\0' && (*p == '{' || *p == ';'))
c = *p++;
if (c == '{')
{
pprevce = &ce->ce_entries;
upce = ce;
ce = NULL;
}
else if (c == ';')
{
if (upce == NULL && !strcasecmp(ce->ce_varname, "include"))
{
subcf = config_load_internal(cf, ce->ce_vardata);
if (subcf == NULL)
{
config_error(cf, "Error in file included from here");
break;
}
lastcf->cf_next = subcf;
while (lastcf->cf_next != NULL)
lastcf = lastcf->cf_next;
}
ce = NULL;
}
else
{
config_error(cf, "Unexpected characters after value %s %s", ce->ce_varname, ce->ce_vardata);
break;
}
}
}
if (!CF_ERRORED(cf) && upce != NULL)
{
config_error(cf, "One or more sections not closed");
ce = upce;
while (ce->ce_prevlevel != NULL)
ce = ce->ce_prevlevel;
if (ce->ce_vardata != NULL)
config_error(cf, "First unclosed section is %s %s at line %d",
ce->ce_varname, ce->ce_vardata, ce->ce_varlinenum);
else
config_error(cf, "First unclosed section is %s at line %d",
ce->ce_varname, ce->ce_varlinenum);
}
if (CF_ERRORED(cf))
{
config_free(cf);
cf = NULL;
}
return cf;
}
static void config_entry_free(config_entry_t *ceptr)
{
config_entry_t *nptr;
for (; ceptr; ceptr = nptr)
{
nptr = ceptr->ce_next;
if (ceptr->ce_entries)
config_entry_free(ceptr->ce_entries);
/* ce_varname and ce_vardata are inside cf_mem */
free(ceptr);
}
}
void config_free(config_file_t *cfptr)
{
config_file_t *nptr;
for (; cfptr; cfptr = nptr)
{
nptr = cfptr->cf_next;
if (cfptr->cf_entries)
config_entry_free(cfptr->cf_entries);
free(cfptr->cf_filename);
free(cfptr->cf_mem);
free(cfptr);
}
}
static config_file_t *config_load_internal(config_file_t *parent, const char *filename)
{
struct stat sb;
FILE *fp;
size_t ret;
char *buf = NULL;
config_file_t *cfptr;
static int nestcnt;
if (nestcnt > MAX_INCLUDE_NESTING)
{
config_error(parent, "Includes nested too deep \"%s\"\n", filename);
return NULL;
}
fp = fopen(filename, "rb");
if (!fp)
{
config_error(parent, "Couldn't open \"%s\": %s\n", filename, strerror(errno));
return NULL;
}
if (stat(filename, &sb) == -1)
{
config_error(parent, "Couldn't fstat \"%s\": %s\n", filename, strerror(errno));
fclose(fp);
return NULL;
}
if (!S_ISREG(sb.st_mode))
{
config_error(parent, "Not a regular file: \"%s\"\n", filename);
fclose(fp);
return NULL;
}
if (sb.st_size > SSIZE_MAX - 1)
{
config_error(parent, "File too large: \"%s\"\n", filename);
fclose(fp);
return NULL;
}
buf = (char *)smalloc(sb.st_size + 1);
if (sb.st_size)
{
errno = 0;
ret = fread(buf, 1, sb.st_size, fp);
if (ret != (size_t)sb.st_size)
{
config_error(parent, "Error reading \"%s\": %s\n", filename, strerror(errno ? errno : EFAULT));
free(buf);
fclose(fp);
return NULL;
}
}
else
ret = 0;
buf[ret] = '\0';
fclose(fp);
nestcnt++;
cfptr = config_parse(filename, buf);
nestcnt--;
/* buf is owned by cfptr or freed now */
return cfptr;
}
config_file_t *config_load(const char *filename)
{
return config_load_internal(NULL, filename);
}
/* vim:cinoptions=>s,e0,n0,f0,{0,}0,^0,=s,ps,t0,c3,+s,(2s,us,)20,*30,gs,hs
* vim:ts=8
* vim:sw=8
* vim:noexpandtab
*/
