Add log configuration ensure watchdog (#1535)

daemon/src/main/cpp/logcat.cpp

@@ -1,17 +1,26 @@
+#include "logcat.h"
+
 #include <jni.h>
 #include <unistd.h>
 #include <string>
 #include <android/log.h>
 #include <array>
 #include <cinttypes>
-#include "logcat.h"
+#include <chrono>
+#include <thread>
 #include <sys/system_properties.h>
 
 using namespace std::string_view_literals;
+using namespace std::chrono_literals;
 
 constexpr size_t kMaxLogSize = 4 * 1024 * 1024;
+#ifdef NDEBUG
 constexpr size_t kLogBufferSize = 256 * 1024;
+#else
+constexpr size_t kLogBufferSize = 4 * 1024 * 1024;
+#endif
 
+namespace {
     constexpr std::array<char, ANDROID_LOG_SILENT + 1> kLogChar = {
             /*ANDROID_LOG_UNKNOWN*/'?',
             /*ANDROID_LOG_DEFAULT*/ '?',
@@ -24,6 +33,60 @@ constexpr std::array<char, ANDROID_LOG_SILENT + 1> kLogChar = {
             /*ANDROID_LOG_SILENT*/ 'S',
     };
 
+    size_t ParseUint(const char *s) {
+        if (s[0] == '\0') return -1;
+
+        while (isspace(*s)) {
+            s++;
+        }
+
+        if (s[0] == '-') {
+            return -1;
+        }
+
+        int base = (s[0] == '0' && (s[1] == 'x' || s[1] == 'X')) ? 16 : 10;
+        char *end;
+        auto result = strtoull(s, &end, base);
+        if (end == s) {
+            return -1;
+        }
+        if (*end != '\0') {
+            const char *suffixes = "bkmgtpe";
+            const char *suffix;
+            if ((suffix = strchr(suffixes, tolower(*end))) == nullptr ||
+                __builtin_mul_overflow(result, 1ULL << (10 * (suffix - suffixes)), &result)) {
+                return -1;
+            }
+        }
+        if (std::numeric_limits<size_t>::max() < result) {
+            return -1;
+        }
+        return static_cast<size_t>(result);
+    }
+
+    inline size_t GetByteProp(std::string_view prop, size_t def = -1) {
+        std::array<char, PROP_VALUE_MAX> buf{};
+        if (__system_property_get(prop.data(), buf.data()) < 0) return def;
+        return ParseUint(buf.data());
+    }
+
+    inline std::string GetStrProp(std::string_view prop, std::string def = {}) {
+        std::array<char, PROP_VALUE_MAX> buf{};
+        if (__system_property_get(prop.data(), buf.data()) < 0) return def;
+        return {buf.data()};
+    }
+
+    inline bool SetIntProp(std::string_view prop, int val) {
+        auto buf = std::to_string(val);
+        return __system_property_set(prop.data(), buf.data()) >= 0;
+    }
+
+    inline bool SetStrProp(std::string_view prop, std::string_view val) {
+        return __system_property_set(prop.data(), val.data()) >= 0;
+    }
+
+}  // namespace
+
 class UniqueFile : public std::unique_ptr<FILE, std::function<void(FILE *)>> {
     inline static deleter_type deleter = [](auto f) { f && f != stdout && fclose(f); };
 public:
@@ -52,6 +115,8 @@ private:
 
     static size_t PrintLogLine(const AndroidLogEntry &entry, FILE *out);
 
+    void EnsureLogWatchDog();
+
     JNIEnv *env_;
     jobject thiz_;
     jmethodID refresh_fd_method_;
@@ -73,7 +138,7 @@ size_t Logcat::PrintLogLine(const AndroidLogEntry &entry, FILE *out) {
     if (!out) return 0;
     constexpr static size_t kMaxTimeBuff = 64;
     struct tm tm{};
-    std::array<char, kMaxTimeBuff> time_buff;
+    std::array<char, kMaxTimeBuff> time_buff{};
 
     auto now = entry.tv_sec;
     auto nsec = entry.tv_nsec;
@@ -122,8 +187,12 @@ void Logcat::RefreshFd(bool is_verbose) {
 }
 
 inline void Logcat::Log(std::string_view str) {
-    if (verbose_) fprintf(verbose_file_.get(), "%.*s", static_cast<int>(str.size()), str.data());
+    if (verbose_) {
+        fprintf(verbose_file_.get(), "%.*s", static_cast<int>(str.size()), str.data());
+        fflush(verbose_file_.get());
+    }
     fprintf(modules_file_.get(), "%.*s", static_cast<int>(str.size()), str.data());
+    fflush(modules_file_.get());
 }
 
 void Logcat::OnCrash() {
@@ -142,7 +211,7 @@ void Logcat::OnCrash() {
         Log("\nLogd maybe crashed, retrying in 1s...\n");
     }
 
-    sleep(1);
+    std::this_thread::sleep_for(1s);
 }
 
 void Logcat::ProcessBuffer(struct log_msg *buf) {
@@ -178,11 +247,46 @@ void Logcat::ProcessBuffer(struct log_msg *buf) {
     }
 }
 
+void Logcat::EnsureLogWatchDog() {
+    constexpr static auto kLogdSizeProp = "persist.logd.size"sv;
+    constexpr static auto kLogdTagProp = "persist.log.tag"sv;
+    constexpr static auto kLogdMainSizeProp = "persist.logd.size.main"sv;
+    constexpr static auto kLogdCrashSizeProp = "persist.logd.size.crash"sv;
+    constexpr static size_t kErr = -1;
+    std::thread([this] {
+        while (true) {
+            auto logd_size = GetByteProp(kLogdSizeProp);
+            auto logd_tag = GetStrProp(kLogdTagProp);
+            auto logd_main_size = GetByteProp(kLogdMainSizeProp);
+            auto logd_crash_size = GetByteProp(kLogdCrashSizeProp);
+            if (!logd_tag.empty() ||
+                !((logd_main_size == kErr && logd_crash_size == kErr && logd_size != kErr &&
+                   logd_size >= kLogBufferSize) ||
+                  (logd_main_size != kErr && logd_main_size >= kLogBufferSize &&
+                   logd_crash_size != kErr &&
+                   logd_crash_size >= kLogBufferSize))) {
+                SetIntProp(kLogdSizeProp, kLogBufferSize);
+                SetIntProp(kLogdMainSizeProp, kLogBufferSize);
+                SetIntProp(kLogdCrashSizeProp, kLogBufferSize);
+                SetStrProp(kLogdTagProp, "");
+                SetStrProp("ctl.start", "logd-reinit");
+                Log("Reset log settings\n");
+            }
+            const auto *pi = __system_property_find(kLogdTagProp.data());
+            uint32_t serial;
+            if (!__system_property_wait(pi, 0, &serial, nullptr)) break;
+        }
+    }).detach();
+}
+
 void Logcat::Run() {
     constexpr size_t tail_after_crash = 10U;
     size_t tail = 0;
     RefreshFd(true);
     RefreshFd(false);
+
+    EnsureLogWatchDog();
+
     while (true) {
         std::unique_ptr<logger_list, decltype(&android_logger_list_free)> logger_list{
                 android_logger_list_alloc(0, tail, 0), &android_logger_list_free};