minix/lib/syslib/ds.c
Ben Gras 3512a86b44 . DS understands publishing and subscribing where keys are in string
form. Subscriptions are regular expressions.
 . different types are stored per key; currently u32 and/or string.
   the same key can be referenced (publish, subscribe, check) as any type.
 . notify()s are sent when subscriptions are triggered (publishing or
   updating of matching keys); optionally, a subscribe flag sends
   updates for all matching keys at subscription time, instead of only
   after updates after subscribing
 . all interfacing to ds is in /usr/src/lib/syslib/ds.c.
 . subscribe is ds_subscribe
   publish functions are ds_publish_<type>
   retrieve functions are ds_retrieve_<type> (one-time retrieval of a value)
   check functions are ds_check_<type> (check for updated key caller
      subscribes to not yet checked for, or ESRCH for none)
 . ramdisk driver updated with new ds interface
2006-07-13 14:50:23 +00:00

260 lines
4.3 KiB
C

#include <minix/ds.h>
#include <string.h>
#include "syslib.h"
int
ds_subscribe(ds_name_regexp, type, flags)
char *ds_name_regexp;
int type;
int flags;
{
int r;
message m;
cp_grant_id_t g;
size_t len;
len = strlen(ds_name_regexp)+1;
g = cpf_grant_direct(DS_PROC_NR,
(vir_bytes) ds_name_regexp, len, CPF_READ);
if(!GRANT_VALID(g))
return -1;
flags &= DS_INITIAL;
m.DS_KEY_GRANT = (char *) g;
m.DS_KEY_LEN = len;
m.DS_FLAGS = flags | (type & DS_TYPE_MASK);
r = _taskcall(DS_PROC_NR, DS_SUBSCRIBE, &m);
cpf_revoke(g);
return r;
}
int ds_publish_u32(ds_name, value)
char *ds_name;
u32_t value;
{
int r;
message m;
cp_grant_id_t g;
size_t len;
len = strlen(ds_name)+1;
g = cpf_grant_direct(DS_PROC_NR,
(vir_bytes) ds_name, len, CPF_READ);
if(!GRANT_VALID(g))
return -1;
m.DS_KEY_GRANT = (char *) g;
m.DS_KEY_LEN = len;
m.DS_FLAGS = DS_TYPE_U32;
m.DS_VAL = value;
m.DS_VAL_LEN = sizeof(value);
r = _taskcall(DS_PROC_NR, DS_PUBLISH, &m);
cpf_revoke(g);
return r;
}
int ds_publish_str(ds_name, value)
char *ds_name;
char *value;
{
int r;
message m;
cp_grant_id_t g_key, g_str;
size_t len_key, len_str;
/* Grant for key. */
len_key = strlen(ds_name)+1;
g_key = cpf_grant_direct(DS_PROC_NR,
(vir_bytes) ds_name, len_key, CPF_READ);
if(!GRANT_VALID(g_key))
return -1;
/* Grant for value. */
len_str = strlen(value)+1;
g_str = cpf_grant_direct(DS_PROC_NR,
(vir_bytes) value, len_str, CPF_READ);
if(!GRANT_VALID(g_str)) {
cpf_revoke(g_key);
return -1;
}
m.DS_KEY_GRANT = (char *) g_key;
m.DS_KEY_LEN = len_key;
m.DS_FLAGS = DS_TYPE_STR;
m.DS_VAL = g_str;
m.DS_VAL_LEN = len_str;
r = _taskcall(DS_PROC_NR, DS_PUBLISH, &m);
cpf_revoke(g_key);
cpf_revoke(g_str);
return r;
}
int ds_retrieve_u32(ds_name, value)
char *ds_name;
u32_t *value;
{
int r;
message m;
cp_grant_id_t g_key;
size_t len_key;
/* Grant for key. */
len_key = strlen(ds_name)+1;
g_key = cpf_grant_direct(DS_PROC_NR,
(vir_bytes) ds_name, len_key, CPF_READ);
if(!GRANT_VALID(g_key))
return -1;
/* Do request. */
m.DS_KEY_GRANT = (char *) g_key;
m.DS_KEY_LEN = len_key;
m.DS_FLAGS = DS_TYPE_U32;
r = _taskcall(DS_PROC_NR, DS_RETRIEVE, &m);
cpf_revoke(g_key);
/* Assign u32 value. */
*value = m.DS_VAL;
return r;
}
int ds_retrieve_str(ds_name, value, len_str)
char *ds_name;
char *value;
size_t len_str;
{
int r;
message m;
cp_grant_id_t g_key, g_str;
size_t len_key;
/* Grant for key. */
len_key = strlen(ds_name)+1;
g_key = cpf_grant_direct(DS_PROC_NR,
(vir_bytes) ds_name, len_key, CPF_READ);
if(!GRANT_VALID(g_key))
return -1;
/* Grant for value. */
g_str = cpf_grant_direct(DS_PROC_NR,
(vir_bytes) value, len_str, CPF_WRITE);
if(!GRANT_VALID(g_str)) {
cpf_revoke(g_key);
return -1;
}
/* Do request. */
m.DS_KEY_GRANT = (char *) g_key;
m.DS_KEY_LEN = len_key;
m.DS_FLAGS = DS_TYPE_STR;
m.DS_VAL = g_str;
m.DS_VAL_LEN = len_str;
r = _taskcall(DS_PROC_NR, DS_RETRIEVE, &m);
cpf_revoke(g_key);
cpf_revoke(g_str);
return r;
}
int ds_check_str(ds_key, len_key, value, len_str)
char *ds_key;
size_t len_key;
char *value;
size_t len_str;
{
int r;
message m;
cp_grant_id_t g_key, g_str;
if(len_key < 1 || len_str < 1) return -1;
/* Grant for key. */
g_key = cpf_grant_direct(DS_PROC_NR,
(vir_bytes) ds_key, len_key, CPF_WRITE);
if(!GRANT_VALID(g_key))
return -1;
/* Grant for value. */
g_str = cpf_grant_direct(DS_PROC_NR,
(vir_bytes) value, len_str, CPF_WRITE);
if(!GRANT_VALID(g_str)) {
cpf_revoke(g_key);
return -1;
}
/* Do request. */
m.DS_KEY_GRANT = (char *) g_key;
m.DS_KEY_LEN = len_key;
m.DS_FLAGS = DS_TYPE_STR;
m.DS_VAL = g_str;
m.DS_VAL_LEN = len_str;
r = _taskcall(DS_PROC_NR, DS_CHECK, &m);
cpf_revoke(g_key);
cpf_revoke(g_str);
ds_key[len_key-1] = '\0';
value[len_str-1] = '\0';
return r;
}
int ds_check_u32(ds_key, len_key, value)
char *ds_key;
size_t len_key;
u32_t *value;
{
int r;
message m;
cp_grant_id_t g_key;
if(len_key < 1) return -1;
/* Grant for key. */
g_key = cpf_grant_direct(DS_PROC_NR,
(vir_bytes) ds_key, len_key, CPF_WRITE);
if(!GRANT_VALID(g_key))
return -1;
/* Do request. */
m.DS_KEY_GRANT = (char *) g_key;
m.DS_KEY_LEN = len_key;
m.DS_FLAGS = DS_TYPE_U32;
r = _taskcall(DS_PROC_NR, DS_CHECK, &m);
cpf_revoke(g_key);
ds_key[len_key-1] = '\0';
/* Assign u32 value. */
*value = m.DS_VAL;
return r;
}