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#include <stdio.h>
#include <dotconf.h>
#include <libpool.h>
/* vim:set ts=4:
vim:set shiftwidth=4:
*/
/*
this is a simple sample structure that we use to keep track
of the current context in the configfile when reading it.
It just has a field for the currently granted permissions.
Later, when the option-table is defined, we'll specify the
the needed permissions for each option.
*/
struct mycontext {
int permissions;
const char *current_end_token;
pool_t *pool;
};
enum permissions {
O_ROOT = 1,
O_SOMESECTION = 2,
O_OTHERSECTION = 4,
O_LAST = 8
};
static DOTCONF_CB(option_SomeSection_open);
static DOTCONF_CB(option_OtherSection_open);
static DOTCONF_CB(common_section_close);
static DOTCONF_CB(common_option);
/*
the constant Section End tokens. We define these separately
to be able to reuse pointers. We need this for our context
'sensitivity' system.
*/
static const char end_SomeSection[] = "</SomeSection>";
static const char end_OtherSection[] = "</OtherSection>";
/*
the last field is used to specify the permissions needed for
each option. These will be checked at runtime by our contextchecker
*/
static const configoption_t options[] = {
{"<SomeSection>", ARG_NONE, option_SomeSection_open, NULL, CTX_ALL},
{end_SomeSection, ARG_NONE, common_section_close, NULL, O_SOMESECTION},
{"<OtherSection>", ARG_NONE, option_OtherSection_open, NULL, CTX_ALL},
{end_OtherSection, ARG_NONE, common_section_close, NULL,
O_OTHERSECTION},
{"RootOption", ARG_NONE, common_option, NULL, CTX_ALL},
{"SomeOption", ARG_NONE, common_option, NULL, O_SOMESECTION},
{"OtherOption", ARG_NONE, common_option, NULL, O_OTHERSECTION},
{"Hybrid", ARG_NONE, common_option, NULL,
O_SOMESECTION | O_OTHERSECTION},
LAST_OPTION
};
const char *context_checker(command_t * cmd, unsigned long mask)
{
struct mycontext *context = cmd->context;
/*
* this test is quite simple: if the permissions needed for the
* to-be-called command are not granted, we'll deny service
*/
/* Root Context granted and Root Context given? */
if (!mask && !context->permissions)
return NULL;
if (!(context->permissions & mask)) {
return pool_strcat(context->pool, "Option '", cmd->name,
"' not allowed in <",
context->current_end_token ? context->
current_end_token + 2 : "global>",
" context", NULL);
}
return NULL;
}
FUNC_ERRORHANDLER(error_handler)
{
fprintf(stderr, "[error] %s\n", msg);
/* continue reading the configfile ; return 1 stop after first error found */
return 0;
}
int main(void)
{
configfile_t *configfile;
struct mycontext context;
context.current_end_token = 0;
context.permissions = 0;
context.pool = pool_new(NULL);
configfile =
dotconf_create("./context.conf", options, (void *)&context,
CASE_INSENSITIVE);
if (!configfile) {
fprintf(stderr, "Error opening configuration file\n");
return 1;
}
configfile->errorhandler = (dotconf_errorhandler_t) error_handler;
configfile->contextchecker = (dotconf_contextchecker_t) context_checker;
if (dotconf_command_loop(configfile) == 0)
fprintf(stderr, "Error reading configuration file\n");
dotconf_cleanup(configfile);
pool_free(context.pool);
return 0;
}
DOTCONF_CB(common_section_close)
{
struct mycontext *context = (struct mycontext *)ctx;
if (!context->current_end_token)
return pool_strcat(context->pool,
cmd->name, " without matching <",
cmd->name + 2, " section", NULL);
if (context->current_end_token != cmd->name)
return pool_strcat(context->pool, "Expected '",
context->current_end_token, "' but saw ",
cmd->name, NULL);
return context->current_end_token;
}
DOTCONF_CB(common_option)
{
printf("Option %s called\n", cmd->name);
return NULL;
}
DOTCONF_CB(option_SomeSection_open)
{
struct mycontext *context = (struct mycontext *)ctx;
const char *old_end_token = context->current_end_token;
int old_override = context->permissions;
const char *err = 0;
if (context->permissions & O_SOMESECTION)
return "<SomeSection> cannot be nested";
context->permissions |= O_SOMESECTION;
context->current_end_token = end_SomeSection;
while (!cmd->configfile->eof) {
err = dotconf_command_loop_until_error(cmd->configfile);
if (!err) {
err = "</SomeSection> is missing";
break;
}
if (err == context->current_end_token)
break;
dotconf_warning(cmd->configfile, DCLOG_ERR, 0, err);
}
context->current_end_token = old_end_token;
context->permissions = old_override;
if (err != end_SomeSection)
return err;
return NULL;
}
DOTCONF_CB(option_OtherSection_open)
{
struct mycontext *context = (struct mycontext *)ctx;
const char *old_end_token = context->current_end_token;
int old_override = context->permissions;
const char *err = 0;
if (context->permissions & O_OTHERSECTION)
return "<OtherSection> Cannot be nested";
context->permissions |= O_OTHERSECTION;
context->current_end_token = end_OtherSection;
while (!cmd->configfile->eof) {
err = dotconf_command_loop_until_error(cmd->configfile);
if (!err) {
err = "</SomeSection> is missing";
break;
}
if (err == context->current_end_token)
break;
dotconf_warning(cmd->configfile, DCLOG_ERR, 0, err);
}
context->current_end_token = old_end_token;
context->permissions = old_override;
if (err != end_OtherSection)
return err;
return NULL;
}
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