Magisk/native/jni/resetprop/persist_properties.cpp
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2020-12-30 22:11:24 -08:00

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#include <pb.h>
#include <pb_decode.h>
#include <pb_encode.h>
#include <utils.hpp>
#include "_resetprop.hpp"
using namespace std;
/* ***********************************************************************
* Auto generated header and field definitions compiled from
* https://android.googlesource.com/platform/system/core/+/master/init/persistent_properties.proto
* Generated with Nanopb: https://github.com/nanopb/nanopb
* ***********************************************************************/
/* Automatically generated nanopb header */
/* Generated by nanopb-0.4.3 */
#if PB_PROTO_HEADER_VERSION != 40
#error Regenerate this file with the current version of nanopb generator.
#endif
/* Struct definitions */
struct PersistentProperties {
pb_callback_t properties;
};
struct PersistentProperties_PersistentPropertyRecord {
pb_callback_t name;
bool has_value;
char value[92];
};
/* Initializer values for message structs */
#define PersistentProperties_init_default {{{NULL}, NULL}}
#define PersistentProperties_PersistentPropertyRecord_init_default {{{NULL}, NULL}, false, ""}
#define PersistentProperties_init_zero {{{NULL}, NULL}}
#define PersistentProperties_PersistentPropertyRecord_init_zero {{{NULL}, NULL}, false, ""}
/* Field tags (for use in manual encoding/decoding) */
#define PersistentProperties_properties_tag 1
#define PersistentProperties_PersistentPropertyRecord_name_tag 1
#define PersistentProperties_PersistentPropertyRecord_value_tag 2
/* Struct field encoding specification for nanopb */
#define PersistentProperties_FIELDLIST(X, a) \
X(a, CALLBACK, REPEATED, MESSAGE, properties, 1)
#define PersistentProperties_CALLBACK pb_default_field_callback
#define PersistentProperties_DEFAULT NULL
#define PersistentProperties_properties_MSGTYPE PersistentProperties_PersistentPropertyRecord
#define PersistentProperties_PersistentPropertyRecord_FIELDLIST(X, a) \
X(a, CALLBACK, OPTIONAL, STRING, name, 1) \
X(a, STATIC, OPTIONAL, STRING, value, 2)
#define PersistentProperties_PersistentPropertyRecord_CALLBACK pb_default_field_callback
#define PersistentProperties_PersistentPropertyRecord_DEFAULT NULL
extern const pb_msgdesc_t PersistentProperties_msg;
extern const pb_msgdesc_t PersistentProperties_PersistentPropertyRecord_msg;
/* Defines for backwards compatibility with code written before nanopb-0.4.0 */
#define PersistentProperties_fields &PersistentProperties_msg
#define PersistentProperties_PersistentPropertyRecord_fields &PersistentProperties_PersistentPropertyRecord_msg
/* Maximum encoded size of messages (where known) */
/* PersistentProperties_size depends on runtime parameters */
/* PersistentProperties_PersistentPropertyRecord_size depends on runtime parameters */
PB_BIND(PersistentProperties, PersistentProperties, AUTO)
PB_BIND(PersistentProperties_PersistentPropertyRecord, PersistentProperties_PersistentPropertyRecord, AUTO)
/* ***************************
* End of auto generated code
* ***************************/
bool use_pb = false;
static bool name_decode(pb_istream_t *stream, const pb_field_t *field, void **arg) {
string &name = *static_cast<string *>(*arg);
name.resize(stream->bytes_left);
return pb_read(stream, (pb_byte_t *)(name.data()), stream->bytes_left);
}
static bool name_encode(pb_ostream_t *stream, const pb_field_t *field, void * const *arg) {
return pb_encode_tag_for_field(stream, field) &&
pb_encode_string(stream, (const pb_byte_t *) *arg, strlen((const char *) *arg));
}
static bool prop_decode(pb_istream_t *stream, const pb_field_t *field, void **arg) {
PersistentProperties_PersistentPropertyRecord prop{};
string name;
prop.name.funcs.decode = name_decode;
prop.name.arg = &name;
if (!pb_decode(stream, &PersistentProperties_PersistentPropertyRecord_msg, &prop))
return false;
auto cb = static_cast<prop_cb*>(*arg);
cb->exec(std::move(name), prop.value);
return true;
}
static bool prop_encode(pb_ostream_t *stream, const pb_field_t *field, void * const *arg) {
PersistentProperties_PersistentPropertyRecord prop{};
prop.name.funcs.encode = name_encode;
prop.has_value = true;
auto &list = *static_cast<prop_list *>(*arg);
for (auto &p : list) {
if (!pb_encode_tag_for_field(stream, field))
return false;
prop.name.arg = (void *) p.first.data();
strcpy(prop.value, p.second.data());
if (!pb_encode_submessage(stream, &PersistentProperties_PersistentPropertyRecord_msg, &prop))
return false;
}
return true;
}
static bool write_callback(pb_ostream_t *stream, const uint8_t *buf, size_t count) {
int fd = (intptr_t)stream->state;
return xwrite(fd, buf, count) == count;
}
static pb_ostream_t create_ostream(const char *filename) {
int fd = creat(filename, 0644);
pb_ostream_t o = {
.callback = write_callback,
.state = (void*)(intptr_t)fd,
.max_size = SIZE_MAX,
.bytes_written = 0,
};
return o;
}
static void pb_getprop(prop_cb *prop_cb) {
LOGD("resetprop: decode with protobuf [" PERSISTENT_PROPERTY_DIR "/persistent_properties]\n");
PersistentProperties props = {};
props.properties.funcs.decode = prop_decode;
props.properties.arg = prop_cb;
pb_byte_t *buf;
size_t size;
mmap_ro(PERSISTENT_PROPERTY_DIR "/persistent_properties", buf, size);
pb_istream_t stream = pb_istream_from_buffer(buf, size);
pb_decode(&stream, &PersistentProperties_msg, &props);
munmap(buf, size);
}
static bool file_getprop(const char *name, char *value) {
char path[4096];
snprintf(path, sizeof(path), PERSISTENT_PROPERTY_DIR "/%s", name);
int fd = open(path, O_RDONLY | O_CLOEXEC);
if (fd < 0)
return false;
LOGD("resetprop: read prop from [%s]\n", path);
value[read(fd, value, PROP_VALUE_MAX - 1)] = '\0'; // Null terminate the read value
close(fd);
return value[0] != '\0';
}
void persist_getprops(prop_cb *prop_cb) {
if (use_pb) {
pb_getprop(prop_cb);
} else {
auto dir = open_dir(PERSISTENT_PROPERTY_DIR);
if (!dir) return;
for (dirent *entry; (entry = xreaddir(dir.get()));) {
char value[PROP_VALUE_MAX];
if (file_getprop(entry->d_name, value))
prop_cb->exec(entry->d_name, value);
}
}
}
struct match_prop_name : prop_cb {
explicit match_prop_name(const char *name) : _name(name) { value[0] = '\0'; }
void exec(string &&name, const char *val) override {
if (name == _name)
strcpy(value, val);
}
char value[PROP_VALUE_MAX];
private:
const char *_name;
};
string persist_getprop(const char *name) {
if (use_pb) {
auto prop = match_prop_name(name);
pb_getprop(&prop);
if (prop.value[0]) {
LOGD("resetprop: getprop (persist) [%s]: [%s]\n", name, prop.value);
return prop.value;
}
} else {
// Try to read from file
char value[PROP_VALUE_MAX];
if (file_getprop(name, value)) {
LOGD("resetprop: getprop (persist) [%s]: [%s]\n", name, value);
return value;
}
}
return string();
}
bool persist_deleteprop(const char *name) {
if (use_pb) {
prop_list list;
prop_collector collector(list);
persist_getprops(&collector);
for (auto it = list.begin(); it != list.end(); ++it) {
if (it->first == name) {
list.erase(it);
// Dump the props back
PersistentProperties props{};
pb_ostream_t ostream = create_ostream(PERSISTENT_PROPERTY_DIR
"/persistent_properties.tmp");
props.properties.funcs.encode = prop_encode;
props.properties.arg = &list;
LOGD("resetprop: encode with protobuf [" PERSISTENT_PROPERTY_DIR
"/persistent_properties.tmp]\n");
if (!pb_encode(&ostream, &PersistentProperties_msg, &props))
return false;
clone_attr(PERSISTENT_PROPERTY_DIR "/persistent_properties",
PERSISTENT_PROPERTY_DIR "/persistent_properties.tmp");
rename(PERSISTENT_PROPERTY_DIR "/persistent_properties.tmp",
PERSISTENT_PROPERTY_DIR "/persistent_properties");
return true;
}
}
return false;
} else {
char path[4096];
snprintf(path, sizeof(path), PERSISTENT_PROPERTY_DIR "/%s", name);
if (unlink(path) == 0) {
LOGD("resetprop: unlink [%s]\n", path);
return true;
}
}
return false;
}