Modernize resetprop with fancy C++

This commit is contained in:
topjohnwu 2020-05-07 06:08:30 -07:00
parent c113f854a2
commit aa8b23105f
4 changed files with 129 additions and 134 deletions

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@ -3,9 +3,10 @@
#include <string> #include <string>
#include <functional> #include <functional>
int prop_exist(const char *name); bool prop_exist(const char *name);
int setprop(const char *name, const char *value, bool trigger = true); int setprop(const char *name, const char *value, bool trigger = true);
std::string getprop(const char *name, bool persist = false); std::string getprop(const char *name, bool persist = false);
void getprop(void (*callback)(const char *, const char *, void *), void *cookie, bool persist = false); void getprops(void (*callback)(const char *, const char *, void *),
void *cookie = nullptr, bool persist = false);
int delprop(const char *name, bool persist = false); int delprop(const char *name, bool persist = false);
void load_prop_file(const char *filename, bool trigger = true); void load_prop_file(const char *filename, bool trigger = true);

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@ -1,57 +1,49 @@
#pragma once #pragma once
#include <string> #include <string>
#include <map>
#include <logging.hpp> #include <logging.hpp>
#include <system_properties.h> #include <system_properties.h>
struct prop_t {
char *name;
char value[PROP_VALUE_MAX];
prop_t() : name(nullptr) {}
explicit prop_t(const char *name) {
this->name = strdup(name);
value[0] = '\0';
}
prop_t(const char *name, const char *value) {
this->name = strdup(name);
strcpy(this->value, value);
}
prop_t(prop_t &&prop): name(nullptr) {
operator=(std::move(prop));
}
bool operator<(const prop_t &prop) const {
return strcmp(name, prop.name) < 0;
}
prop_t& operator=(prop_t &&prop) {
if (this != &prop) {
free(name);
name = prop.name;
strcpy(value, prop.value);
prop.name = nullptr;
}
return *this;
};
~prop_t() {
free(name);
}
};
struct read_cb_t {
void (*cb)(const char *, const char *, void *);
void *arg;
explicit read_cb_t(void (*cb)(const char *, const char *, void *) = nullptr, void *arg = nullptr)
: cb(cb), arg(arg) {}
void exec(const char *name, const char *value) {
cb(name, value, arg);
}
};
#define PERSISTENT_PROPERTY_DIR "/data/property" #define PERSISTENT_PROPERTY_DIR "/data/property"
struct prop_cb {
virtual void exec(const char *name, const char *value) = 0;
};
template<class T>
struct prop_cb_impl : public prop_cb {
typedef void (*callback_type)(const char *, const char *, T&);
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wdangling-field" // Dangling field is expected
prop_cb_impl(T &arg, callback_type fn) : arg(arg), fn(fn) {}
#pragma GCC diagnostic pop
void exec(const char *name, const char *value) override {
fn(name, value, arg);
}
private:
T &arg;
callback_type fn;
};
extern bool use_pb; extern bool use_pb;
using prop_list = std::map<std::string_view, std::string>;
struct prop_collector : prop_cb_impl<prop_list> {
prop_collector(prop_list &list) :
prop_cb_impl<prop_list>(list, [](auto name, auto val, auto list){ list.emplace(name, val); }) {}
};
template <class T, class Func>
prop_cb_impl<T> make_prop_cb(T &arg, Func f) {
return prop_cb_impl<T>(arg, f);
}
std::string persist_getprop(const char *name); std::string persist_getprop(const char *name);
void persist_getprop(read_cb_t *read_cb); void persist_getprops(prop_cb *prop_cb);
bool persist_deleteprop(const char *name); bool persist_deleteprop(const char *name);
void collect_props(const char *name, const char *value, void *v_plist); void persist_cleanup();

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@ -88,8 +88,22 @@ const pb_field_t PersistentProperties_fields[2] = {
* End of auto generated code * End of auto generated code
* ***************************/ * ***************************/
#ifdef APPLET_STUB_MAIN
struct {
void push_back(...){};
} allocs;
void persist_cleanup(){}
#else
static thread_local vector<void *> allocs;
void persist_cleanup() {
std::for_each(allocs.begin(), allocs.end(), [](auto p){ free(p); });
allocs.clear();
}
#endif
static bool name_decode(pb_istream_t *stream, const pb_field_t *field, void **arg) { static bool name_decode(pb_istream_t *stream, const pb_field_t *field, void **arg) {
auto name = new pb_byte_t[stream->bytes_left + 1]; auto name = (pb_byte_t *) malloc(stream->bytes_left + 1);
allocs.push_back(name); /* Record all mallocs to cleanup */
name[stream->bytes_left] = '\0'; name[stream->bytes_left] = '\0';
if (!pb_read(stream, name, stream->bytes_left)) if (!pb_read(stream, name, stream->bytes_left))
return false; return false;
@ -107,8 +121,7 @@ static bool prop_decode(pb_istream_t *stream, const pb_field_t *field, void **ar
prop.name.funcs.decode = name_decode; prop.name.funcs.decode = name_decode;
if (!pb_decode(stream, PersistentProperties_PersistentPropertyRecord_fields, &prop)) if (!pb_decode(stream, PersistentProperties_PersistentPropertyRecord_fields, &prop))
return false; return false;
((read_cb_t *) *arg)->exec((const char *) prop.name.arg, prop.value); reinterpret_cast<prop_cb*>(*arg)->exec((const char *) prop.name.arg, prop.value);
delete[] (pb_byte_t *) prop.name.arg;
return true; return true;
} }
@ -116,12 +129,12 @@ static bool prop_encode(pb_ostream_t *stream, const pb_field_t *field, void * co
PersistentProperties_PersistentPropertyRecord prop = {}; PersistentProperties_PersistentPropertyRecord prop = {};
prop.name.funcs.encode = name_encode; prop.name.funcs.encode = name_encode;
prop.has_value = true; prop.has_value = true;
auto &prop_list = *(vector<prop_t> *) *arg; auto &list = *(prop_list *) *arg;
for (auto &p : prop_list) { for (auto &p : list) {
if (!pb_encode_tag_for_field(stream, field)) if (!pb_encode_tag_for_field(stream, field))
return false; return false;
prop.name.arg = p.name; prop.name.arg = (void *) p.first.data();
strcpy(prop.value, p.value); strcpy(prop.value, p.second.data());
if (!pb_encode_submessage(stream, PersistentProperties_PersistentPropertyRecord_fields, &prop)) if (!pb_encode_submessage(stream, PersistentProperties_PersistentPropertyRecord_fields, &prop))
return false; return false;
} }
@ -144,17 +157,11 @@ static pb_ostream_t create_ostream(const char *filename) {
return o; return o;
} }
static void pb_getprop_cb(const char *name, const char *value, void *v) { static void pb_getprop(prop_cb *prop_cb) {
struct prop_t *prop = static_cast<prop_t *>(v);
if (prop->name && strcmp(name, prop->name) == 0)
strcpy(prop->value, value);
}
static void pb_getprop(read_cb_t *read_cb) {
LOGD("resetprop: decode with protobuf [" PERSISTENT_PROPERTY_DIR "/persistent_properties]\n"); LOGD("resetprop: decode with protobuf [" PERSISTENT_PROPERTY_DIR "/persistent_properties]\n");
PersistentProperties props = {}; PersistentProperties props = {};
props.properties.funcs.decode = prop_decode; props.properties.funcs.decode = prop_decode;
props.properties.arg = read_cb; props.properties.arg = prop_cb;
pb_byte_t *buf; pb_byte_t *buf;
size_t size; size_t size;
mmap_ro(PERSISTENT_PROPERTY_DIR "/persistent_properties", buf, size); mmap_ro(PERSISTENT_PROPERTY_DIR "/persistent_properties", buf, size);
@ -175,9 +182,9 @@ static bool file_getprop(const char *name, char *value) {
return value[0] != '\0'; return value[0] != '\0';
} }
void persist_getprop(read_cb_t *read_cb) { void persist_getprops(prop_cb *prop_cb) {
if (use_pb) { if (use_pb) {
pb_getprop(read_cb); pb_getprop(prop_cb);
} else { } else {
DIR *dir = opendir(PERSISTENT_PROPERTY_DIR); DIR *dir = opendir(PERSISTENT_PROPERTY_DIR);
struct dirent *entry; struct dirent *entry;
@ -186,16 +193,25 @@ void persist_getprop(read_cb_t *read_cb) {
continue; continue;
char value[PROP_VALUE_MAX]; char value[PROP_VALUE_MAX];
if (file_getprop(entry->d_name, value)) if (file_getprop(entry->d_name, value))
read_cb->exec(entry->d_name, value); prop_cb->exec(entry->d_name, value);
} }
} }
} }
string persist_getprop(const char *name) { string persist_getprop(const char *name) {
prop_t prop(name);
if (use_pb) { if (use_pb) {
read_cb_t read_cb(pb_getprop_cb, &prop); run_finally f([]{ persist_cleanup(); });
pb_getprop(&read_cb); struct {
const char *name;
char value[PROP_VALUE_MAX];
} prop;
prop.name = name;
prop.value[0] = '\0';
auto reader = make_prop_cb(prop, [](auto name, auto value, auto prop) {
if (strcmp(name, prop.name) == 0)
strcpy(prop.value, value);
});
pb_getprop(&reader);
if (prop.value[0]) if (prop.value[0])
return prop.value; return prop.value;
} else { } else {
@ -209,19 +225,20 @@ string persist_getprop(const char *name) {
bool persist_deleteprop(const char *name) { bool persist_deleteprop(const char *name) {
if (use_pb) { if (use_pb) {
vector<prop_t> prop_list; run_finally f([]{ persist_cleanup(); });
read_cb_t read_cb(collect_props, &prop_list); prop_list list;
persist_getprop(&read_cb); prop_collector collector(list);
persist_getprops(&collector);
for (auto it = prop_list.begin(); it != prop_list.end(); ++it) { for (auto it = list.begin(); it != list.end(); ++it) {
if (strcmp(it->name, name) == 0) { if (it->first == name) {
prop_list.erase(it); list.erase(it);
// Dump the props back // Dump the props back
PersistentProperties props = PersistentProperties_init_zero; PersistentProperties props = PersistentProperties_init_zero;
pb_ostream_t ostream = create_ostream(PERSISTENT_PROPERTY_DIR pb_ostream_t ostream = create_ostream(PERSISTENT_PROPERTY_DIR
"/persistent_properties.tmp"); "/persistent_properties.tmp");
props.properties.funcs.encode = prop_encode; props.properties.funcs.encode = prop_encode;
props.properties.arg = &prop_list; props.properties.arg = &list;
LOGD("resetprop: encode with protobuf [" PERSISTENT_PROPERTY_DIR LOGD("resetprop: encode with protobuf [" PERSISTENT_PROPERTY_DIR
"/persistent_properties.tmp]\n"); "/persistent_properties.tmp]\n");
if (!pb_encode(&ostream, PersistentProperties_fields, &props)) if (!pb_encode(&ostream, PersistentProperties_fields, &props))
@ -233,7 +250,6 @@ bool persist_deleteprop(const char *name) {
return true; return true;
} }
} }
return false; return false;
} else { } else {
char path[PATH_MAX]; char path[PATH_MAX];

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@ -7,7 +7,7 @@
#include <dirent.h> #include <dirent.h>
#include <sys/types.h> #include <sys/types.h>
#include <vector> #include <vector>
#include <algorithm> #include <map>
#include <logging.hpp> #include <logging.hpp>
#include <resetprop.hpp> #include <resetprop.hpp>
@ -55,48 +55,34 @@ illegal:
[[noreturn]] static void usage(char* arg0) { [[noreturn]] static void usage(char* arg0) {
fprintf(stderr, fprintf(stderr,
NAME_WITH_VER(resetprop) " - System Props Modification Tool\n\n" NAME_WITH_VER(resetprop) R"EOF(" - System Props Modification Tool
"Usage: %s [flags] [options...]\n"
"\n"
"Options:\n"
" -h, --help show this message\n"
" (no arguments) print all properties\n"
" NAME get property\n"
" NAME VALUE set property entry NAME with VALUE\n"
" --file FILE load props from FILE\n"
" --delete NAME delete property\n"
"\n"
"Flags:\n"
" -v print verbose output to stderr\n"
" -n set properties without init triggers\n"
" only affects setprop\n"
" -p access actual persist storage\n"
" only affects getprop and delprop\n"
"\n"
, arg0); Usage: %s [flags] [options...]
Options:
-h, --help show this message
(no arguments) print all properties
NAME get property
NAME VALUE set property entry NAME with VALUE
--file FILE load props from FILE
--delete NAME delete property
Flags:
-v print verbose output to stderr
-n set properties without going through init
affects setprop and prop file loading
-p also access props directly from persist storage
affects getprop and delprop
)EOF", arg0);
exit(1); exit(1);
} }
static void read_props(const prop_info *pi, void *read_cb) { static void read_props(const prop_info *pi, void *cb) {
__system_property_read_callback( __system_property_read_callback(
pi, [](auto cb, auto name, auto value, auto) { pi, [](auto cb, auto name, auto value, auto) {
((read_cb_t *) cb)->exec(name, value); reinterpret_cast<prop_cb*>(cb)->exec(name, value);
}, read_cb); }, cb);
}
void collect_props(const char *name, const char *value, void *v_plist) {
auto prop_list = static_cast<vector<prop_t> *>(v_plist);
prop_list->emplace_back(name, value);
}
static void collect_unique_props(const char *name, const char *value, void *v_plist) {
auto &prop_list = *static_cast<vector<prop_t> *>(v_plist);
for (auto &prop : prop_list) {
if (strcmp(name, prop.name) == 0)
return;
}
collect_props(name, value, v_plist);
} }
static int init_resetprop() { static int init_resetprop() {
@ -109,11 +95,9 @@ static int init_resetprop() {
} }
static void print_props(bool persist) { static void print_props(bool persist) {
vector<prop_t> prop_list; getprops([](auto name, auto value, auto) {
getprop(collect_props, &prop_list, persist); printf("[%s]: [%s]\n", name, value);
sort(prop_list.begin(), prop_list.end()); }, nullptr, persist);
for (auto &prop : prop_list)
printf("[%s]: [%s]\n", prop.name, prop.value);
} }
/* ************************************************** /* **************************************************
@ -122,8 +106,8 @@ static void print_props(bool persist) {
#define ENSURE_INIT(ret) if (init_resetprop()) return ret #define ENSURE_INIT(ret) if (init_resetprop()) return ret
int prop_exist(const char *name) { bool prop_exist(const char *name) {
ENSURE_INIT(0); ENSURE_INIT(false);
return __system_property_find(name) != nullptr; return __system_property_find(name) != nullptr;
} }
@ -137,29 +121,31 @@ string getprop(const char *name, bool persist) {
if (persist && strncmp(name, "persist.", 8) == 0) { if (persist && strncmp(name, "persist.", 8) == 0) {
auto value = persist_getprop(name); auto value = persist_getprop(name);
if (value.empty()) if (value.empty())
LOGD("resetprop: prop [%s] does not exist\n", name); goto not_found;
return value; return value;
} }
not_found:
LOGD("resetprop: prop [%s] does not exist\n", name);
return string(); return string();
} else { } else {
char value[PROP_VALUE_MAX]; char buf[PROP_VALUE_MAX];
read_cb_t read_cb; auto reader = make_prop_cb(buf, [](auto, auto value, auto buf) { strcpy(buf, value); });
read_cb.cb = [](auto, auto value, auto dst) -> void { strcpy((char *) dst, value); }; read_props(pi, &reader);
read_cb.arg = value; LOGD("resetprop: getprop [%s]: [%s]\n", name, buf);
read_props(pi, &read_cb); return buf;
LOGD("resetprop: getprop [%s]: [%s]\n", name, value);
return value;
} }
} }
void getprop(void (*callback)(const char *, const char *, void *), void *cookie, bool persist) { void getprops(void (*callback)(const char *, const char *, void *), void *cookie, bool persist) {
ENSURE_INIT(); ENSURE_INIT();
read_cb_t read_cb(callback, cookie); prop_list list;
__system_property_foreach(read_props, &read_cb); prop_collector collector(list);
if (persist) { __system_property_foreach(read_props, &collector);
read_cb.cb = collect_unique_props; if (persist)
persist_getprop(&read_cb); persist_getprops(&collector);
} for (auto &[key, val] : list)
callback(key.data(), val.data(), cookie);
persist_cleanup();
} }
int setprop(const char *name, const char *value, bool trigger) { int setprop(const char *name, const char *value, bool trigger) {