* SUCH DAMAGE.
*/
#include <stdio.h>
+#include <stdint.h>
#include <stdlib.h>
#include <unistd.h>
#include <stddef.h>
#include <sys/atomics.h>
+struct prop_area {
+ unsigned volatile count;
+ unsigned volatile serial;
+ unsigned magic;
+ unsigned version;
+ unsigned reserved[4];
+ unsigned toc[1];
+};
+
+typedef struct prop_area prop_area;
+
+struct prop_info {
+ char name[PROP_NAME_MAX];
+ unsigned volatile serial;
+ char value[PROP_VALUE_MAX];
+};
+
+typedef struct prop_info prop_info;
+
static const char property_service_socket[] = "/dev/socket/" PROP_SERVICE_NAME;
static unsigned dummy_props = 0;
return atoi(env);
}
+void __system_property_area_init(void *data)
+{
+ prop_area *pa = data;
+ memset(pa, 0, PA_SIZE);
+ pa->magic = PROP_AREA_MAGIC;
+ pa->version = PROP_AREA_VERSION;
+
+ /* plug into the lib property services */
+ __system_property_area__ = pa;
+}
+
int __system_properties_init(void)
{
bool fromFile = true;
unsigned len = strlen(name);
prop_info *pi;
+ if (len >= PROP_NAME_MAX)
+ return 0;
+ if (len < 1)
+ return 0;
+
while(count--) {
unsigned entry = *toc++;
if(TOC_NAME_LEN(entry) != len) continue;
}
return 0;
}
+
+int __system_property_update(prop_info *pi, const char *value, unsigned int len)
+{
+ prop_area *pa = __system_property_area__;
+
+ if (len >= PROP_VALUE_MAX)
+ return -1;
+
+ pi->serial = pi->serial | 1;
+ memcpy(pi->value, value, len + 1);
+ pi->serial = (len << 24) | ((pi->serial + 1) & 0xffffff);
+ __futex_wake(&pi->serial, INT32_MAX);
+
+ pa->serial++;
+ __futex_wake(&pa->serial, INT32_MAX);
+
+ return 0;
+}
+
+int __system_property_add(const char *name, unsigned int namelen,
+ const char *value, unsigned int valuelen)
+{
+ prop_area *pa = __system_property_area__;
+ prop_info *pa_info_array = (void*) (((char*) pa) + PA_INFO_START);
+ prop_info *pi;
+
+ if (pa->count == PA_COUNT_MAX)
+ return -1;
+ if (namelen >= PROP_NAME_MAX)
+ return -1;
+ if (valuelen >= PROP_VALUE_MAX)
+ return -1;
+ if (namelen < 1)
+ return -1;
+
+ pi = pa_info_array + pa->count;
+ pi->serial = (valuelen << 24);
+ memcpy(pi->name, name, namelen + 1);
+ memcpy(pi->value, value, valuelen + 1);
+
+ pa->toc[pa->count] =
+ (namelen << 24) | (((unsigned) pi) - ((unsigned) pa));
+
+ pa->count++;
+ pa->serial++;
+ __futex_wake(&pa->serial, INT32_MAX);
+
+ return 0;
+}
+
+unsigned int __system_property_serial(const prop_info *pi)
+{
+ return pi->serial;
+}
+
+unsigned int __system_property_wait_any(unsigned int serial)
+{
+ prop_area *pa = __system_property_area__;
+
+ do {
+ __futex_wait(&pa->serial, serial, 0);
+ } while(pa->serial == serial);
+
+ return pa->serial;
+}
#else
#include <sys/system_properties.h>
-typedef struct prop_area prop_area;
typedef struct prop_msg prop_msg;
#define PROP_AREA_MAGIC 0x504f5250
#define PROP_SERVICE_NAME "property_service"
#define PROP_FILENAME "/dev/__properties__"
-/* #define PROP_MAX_ENTRIES 247 */
-/* 247 -> 32620 bytes (<32768) */
+/* (8 header words + 247 toc words) = 1020 bytes */
+/* 1024 bytes header and toc + 247 prop_infos @ 128 bytes = 32640 bytes */
+
+#define PA_COUNT_MAX 247
+#define PA_INFO_START 1024
+#define PA_SIZE 32768
#define TOC_NAME_LEN(toc) ((toc) >> 24)
#define TOC_TO_INFO(area, toc) ((prop_info*) (((char*) area) + ((toc) & 0xFFFFFF)))
-struct prop_area {
- unsigned volatile count;
- unsigned volatile serial;
- unsigned magic;
- unsigned version;
- unsigned reserved[4];
- unsigned toc[1];
-};
-
#define SERIAL_VALUE_LEN(serial) ((serial) >> 24)
#define SERIAL_DIRTY(serial) ((serial) & 1)
-struct prop_info {
- char name[PROP_NAME_MAX];
- unsigned volatile serial;
- char value[PROP_VALUE_MAX];
-};
+__BEGIN_DECLS
struct prop_msg
{
#define PROP_PATH_LOCAL_OVERRIDE "/data/local.prop"
#define PROP_PATH_FACTORY "/factory/factory.prop"
+/*
+** Initialize the area to be used to store properties. Can
+** only be done by a single process that has write access to
+** the property area.
+*/
+void __system_property_area_init(void *data);
+
+/* Add a new system property. Can only be done by a single
+** process that has write access to the property area, and
+** that process must handle sequencing to ensure the property
+** does not already exist and that only one property is added
+** or updated at a time.
+**
+** Returns 0 on success, -1 if the property area is full.
+*/
+int __system_property_add(const char *name, unsigned int namelen,
+ const char *value, unsigned int valuelen);
+
+/* Update the value of a system property returned by
+** __system_property_find. Can only be done by a single process
+** that has write access to the property area, and that process
+** must handle sequencing to ensure that only one property is
+** updated at a time.
+**
+** Returns 0 on success, -1 if the parameters are incorrect.
+*/
+int __system_property_update(prop_info *pi, const char *value, unsigned int len);
+
+/* Read the serial number of a system property returned by
+** __system_property_find.
+**
+** Returns the serial number on success, -1 on error.
+*/
+unsigned int __system_property_serial(const prop_info *pi);
+
+/* Wait for any system property to be updated. Caller must pass
+** in 0 the first time, and the previous return value on each
+** successive call. */
+unsigned int __system_property_wait_any(unsigned int serial);
+
+__END_DECLS
+
#endif
#endif
rt->_serial = 0;
rt->_pi = (struct prop_info*) __system_property_find("net.change");
if (rt->_pi) {
- rt->_serial = rt->_pi->serial;
+ rt->_serial = __system_property_serial(rt->_pi);
}
memset(rt->_rstatic, 0, sizeof rt->_rstatic);
}
return rt;
}
}
- if (rt->_serial == rt->_pi->serial) {
+ if (rt->_serial == __system_property_serial(rt->_pi)) {
/* Nothing changed, so return the current state */
D("%s: tid=%d rt=%p nothing changed, returning",
__FUNCTION__, gettid(), rt);
return rt;
}
/* Update the recorded serial number, and go reset the state */
- rt->_serial = rt->_pi->serial;
+ rt->_serial = __system_property_serial(rt->_pi);
goto RESET_STATE;
}
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