liblog: convert to C++
Bug: 119867234
Test: liblog, logcat, logd unit tests
Change-Id: I2a33b6fc37f9860c0041e3573bfb59ea389f623c
diff --git a/liblog/logger_write.cpp b/liblog/logger_write.cpp
new file mode 100644
index 0000000..fbe6874
--- /dev/null
+++ b/liblog/logger_write.cpp
@@ -0,0 +1,709 @@
+/*
+ * Copyright (C) 2007-2016 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <errno.h>
+#include <stdatomic.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/time.h>
+
+#ifdef __BIONIC__
+#include <android/set_abort_message.h>
+#endif
+
+#include <log/event_tag_map.h>
+#include <log/log_transport.h>
+#include <private/android_filesystem_config.h>
+#include <private/android_logger.h>
+
+#include "config_read.h" /* __android_log_config_read_close() definition */
+#include "config_write.h"
+#include "log_portability.h"
+#include "logger.h"
+
+#define LOG_BUF_SIZE 1024
+
+static int __write_to_log_init(log_id_t, struct iovec* vec, size_t nr);
+static int (*write_to_log)(log_id_t, struct iovec* vec, size_t nr) = __write_to_log_init;
+
+/*
+ * This is used by the C++ code to decide if it should write logs through
+ * the C code. Basically, if /dev/socket/logd is available, we're running in
+ * the simulator rather than a desktop tool and want to use the device.
+ */
+static enum { kLogUninitialized, kLogNotAvailable, kLogAvailable } g_log_status = kLogUninitialized;
+
+static int check_log_uid_permissions() {
+#if defined(__ANDROID__)
+ uid_t uid = __android_log_uid();
+
+ /* Matches clientHasLogCredentials() in logd */
+ if ((uid != AID_SYSTEM) && (uid != AID_ROOT) && (uid != AID_LOG)) {
+ uid = geteuid();
+ if ((uid != AID_SYSTEM) && (uid != AID_ROOT) && (uid != AID_LOG)) {
+ gid_t gid = getgid();
+ if ((gid != AID_SYSTEM) && (gid != AID_ROOT) && (gid != AID_LOG)) {
+ gid = getegid();
+ if ((gid != AID_SYSTEM) && (gid != AID_ROOT) && (gid != AID_LOG)) {
+ int num_groups;
+ gid_t* groups;
+
+ num_groups = getgroups(0, NULL);
+ if (num_groups <= 0) {
+ return -EPERM;
+ }
+ groups = static_cast<gid_t*>(calloc(num_groups, sizeof(gid_t)));
+ if (!groups) {
+ return -ENOMEM;
+ }
+ num_groups = getgroups(num_groups, groups);
+ while (num_groups > 0) {
+ if (groups[num_groups - 1] == AID_LOG) {
+ break;
+ }
+ --num_groups;
+ }
+ free(groups);
+ if (num_groups <= 0) {
+ return -EPERM;
+ }
+ }
+ }
+ }
+ }
+#endif
+ return 0;
+}
+
+static void __android_log_cache_available(struct android_log_transport_write* node) {
+ uint32_t i;
+
+ if (node->logMask) {
+ return;
+ }
+
+ for (i = LOG_ID_MIN; i < LOG_ID_MAX; ++i) {
+ if (node->write && (i != LOG_ID_KERNEL) &&
+ ((i != LOG_ID_SECURITY) || (check_log_uid_permissions() == 0)) &&
+ (!node->available || ((*node->available)(static_cast<log_id_t>(i)) >= 0))) {
+ node->logMask |= 1 << i;
+ }
+ }
+}
+
+LIBLOG_ABI_PUBLIC extern "C" int __android_log_dev_available() {
+ struct android_log_transport_write* node;
+
+ if (list_empty(&__android_log_transport_write)) {
+ return kLogUninitialized;
+ }
+
+ write_transport_for_each(node, &__android_log_transport_write) {
+ __android_log_cache_available(node);
+ if (node->logMask) {
+ return kLogAvailable;
+ }
+ }
+ return kLogNotAvailable;
+}
+
+#if defined(__ANDROID__)
+static atomic_uintptr_t tagMap;
+#endif
+
+/*
+ * Release any logger resources. A new log write will immediately re-acquire.
+ */
+LIBLOG_ABI_PUBLIC void __android_log_close() {
+ struct android_log_transport_write* transport;
+#if defined(__ANDROID__)
+ EventTagMap* m;
+#endif
+
+ __android_log_lock();
+
+ write_to_log = __write_to_log_init;
+
+ /*
+ * Threads that are actively writing at this point are not held back
+ * by a lock and are at risk of dropping the messages with a return code
+ * -EBADF. Prefer to return error code than add the overhead of a lock to
+ * each log writing call to guarantee delivery. In addition, anyone
+ * calling this is doing so to release the logging resources and shut down,
+ * for them to do so with outstanding log requests in other threads is a
+ * disengenuous use of this function.
+ */
+
+ write_transport_for_each(transport, &__android_log_persist_write) {
+ if (transport->close) {
+ (*transport->close)();
+ }
+ }
+
+ write_transport_for_each(transport, &__android_log_transport_write) {
+ if (transport->close) {
+ (*transport->close)();
+ }
+ }
+
+ __android_log_config_write_close();
+
+#if defined(__ANDROID__)
+ /*
+ * Additional risk here somewhat mitigated by immediately unlock flushing
+ * the processor cache. The multi-threaded race that we choose to accept,
+ * to minimize locking, is an atomic_load in a writer picking up a value
+ * just prior to entering this routine. There will be an use after free.
+ *
+ * Again, anyone calling this is doing so to release the logging resources
+ * is most probably going to quiesce then shut down; or to restart after
+ * a fork so the risk should be non-existent. For this reason we
+ * choose a mitigation stance for efficiency instead of incuring the cost
+ * of a lock for every log write.
+ */
+ m = (EventTagMap*)atomic_exchange(&tagMap, (uintptr_t)0);
+#endif
+
+ __android_log_unlock();
+
+#if defined(__ANDROID__)
+ if (m != (EventTagMap*)(uintptr_t)-1LL) android_closeEventTagMap(m);
+#endif
+}
+
+/* log_init_lock assumed */
+static int __write_to_log_initialize() {
+ struct android_log_transport_write* transport;
+ struct listnode* n;
+ int i = 0, ret = 0;
+
+ __android_log_config_write();
+ write_transport_for_each_safe(transport, n, &__android_log_transport_write) {
+ __android_log_cache_available(transport);
+ if (!transport->logMask) {
+ list_remove(&transport->node);
+ continue;
+ }
+ if (!transport->open || ((*transport->open)() < 0)) {
+ if (transport->close) {
+ (*transport->close)();
+ }
+ list_remove(&transport->node);
+ continue;
+ }
+ ++ret;
+ }
+ write_transport_for_each_safe(transport, n, &__android_log_persist_write) {
+ __android_log_cache_available(transport);
+ if (!transport->logMask) {
+ list_remove(&transport->node);
+ continue;
+ }
+ if (!transport->open || ((*transport->open)() < 0)) {
+ if (transport->close) {
+ (*transport->close)();
+ }
+ list_remove(&transport->node);
+ continue;
+ }
+ ++i;
+ }
+ if (!ret && !i) {
+ return -ENODEV;
+ }
+
+ return ret;
+}
+
+/*
+ * Extract a 4-byte value from a byte stream. le32toh open coded
+ */
+static inline uint32_t get4LE(const uint8_t* src) {
+ return src[0] | (src[1] << 8) | (src[2] << 16) | (src[3] << 24);
+}
+
+static int __write_to_log_daemon(log_id_t log_id, struct iovec* vec, size_t nr) {
+ struct android_log_transport_write* node;
+ int ret, save_errno;
+ struct timespec ts;
+ size_t len, i;
+
+ for (len = i = 0; i < nr; ++i) {
+ len += vec[i].iov_len;
+ }
+ if (!len) {
+ return -EINVAL;
+ }
+
+ save_errno = errno;
+#if defined(__ANDROID__)
+ clock_gettime(android_log_clockid(), &ts);
+
+ if (log_id == LOG_ID_SECURITY) {
+ if (vec[0].iov_len < 4) {
+ errno = save_errno;
+ return -EINVAL;
+ }
+
+ ret = check_log_uid_permissions();
+ if (ret < 0) {
+ errno = save_errno;
+ return ret;
+ }
+ if (!__android_log_security()) {
+ /* If only we could reset downstream logd counter */
+ errno = save_errno;
+ return -EPERM;
+ }
+ } else if (log_id == LOG_ID_EVENTS || log_id == LOG_ID_STATS) {
+ const char* tag;
+ size_t len;
+ EventTagMap *m, *f;
+
+ if (vec[0].iov_len < 4) {
+ errno = save_errno;
+ return -EINVAL;
+ }
+
+ tag = NULL;
+ len = 0;
+ f = NULL;
+ m = (EventTagMap*)atomic_load(&tagMap);
+
+ if (!m) {
+ ret = __android_log_trylock();
+ m = (EventTagMap*)atomic_load(&tagMap); /* trylock flush cache */
+ if (!m) {
+ m = android_openEventTagMap(NULL);
+ if (ret) { /* trylock failed, use local copy, mark for close */
+ f = m;
+ } else {
+ if (!m) { /* One chance to open map file */
+ m = (EventTagMap*)(uintptr_t)-1LL;
+ }
+ atomic_store(&tagMap, (uintptr_t)m);
+ }
+ }
+ if (!ret) { /* trylock succeeded, unlock */
+ __android_log_unlock();
+ }
+ }
+ if (m && (m != (EventTagMap*)(uintptr_t)-1LL)) {
+ tag = android_lookupEventTag_len(m, &len, get4LE(static_cast<uint8_t*>(vec[0].iov_base)));
+ }
+ ret = __android_log_is_loggable_len(ANDROID_LOG_INFO, tag, len, ANDROID_LOG_VERBOSE);
+ if (f) { /* local copy marked for close */
+ android_closeEventTagMap(f);
+ }
+ if (!ret) {
+ errno = save_errno;
+ return -EPERM;
+ }
+ } else {
+ /* Validate the incoming tag, tag content can not split across iovec */
+ char prio = ANDROID_LOG_VERBOSE;
+ const char* tag = static_cast<const char*>(vec[0].iov_base);
+ size_t len = vec[0].iov_len;
+ if (!tag) {
+ len = 0;
+ }
+ if (len > 0) {
+ prio = *tag;
+ if (len > 1) {
+ --len;
+ ++tag;
+ } else {
+ len = vec[1].iov_len;
+ tag = ((const char*)vec[1].iov_base);
+ if (!tag) {
+ len = 0;
+ }
+ }
+ }
+ /* tag must be nul terminated */
+ if (tag && strnlen(tag, len) >= len) {
+ tag = NULL;
+ }
+
+ if (!__android_log_is_loggable_len(prio, tag, len - 1, ANDROID_LOG_VERBOSE)) {
+ errno = save_errno;
+ return -EPERM;
+ }
+ }
+#else
+ /* simulate clock_gettime(CLOCK_REALTIME, &ts); */
+ {
+ struct timeval tv;
+ gettimeofday(&tv, NULL);
+ ts.tv_sec = tv.tv_sec;
+ ts.tv_nsec = tv.tv_usec * 1000;
+ }
+#endif
+
+ ret = 0;
+ i = 1 << log_id;
+ write_transport_for_each(node, &__android_log_transport_write) {
+ if (node->logMask & i) {
+ ssize_t retval;
+ retval = (*node->write)(log_id, &ts, vec, nr);
+ if (ret >= 0) {
+ ret = retval;
+ }
+ }
+ }
+
+ write_transport_for_each(node, &__android_log_persist_write) {
+ if (node->logMask & i) {
+ (void)(*node->write)(log_id, &ts, vec, nr);
+ }
+ }
+
+ errno = save_errno;
+ return ret;
+}
+
+static int __write_to_log_init(log_id_t log_id, struct iovec* vec, size_t nr) {
+ int ret, save_errno = errno;
+
+ __android_log_lock();
+
+ if (write_to_log == __write_to_log_init) {
+ ret = __write_to_log_initialize();
+ if (ret < 0) {
+ __android_log_unlock();
+ if (!list_empty(&__android_log_persist_write)) {
+ __write_to_log_daemon(log_id, vec, nr);
+ }
+ errno = save_errno;
+ return ret;
+ }
+
+ write_to_log = __write_to_log_daemon;
+ }
+
+ __android_log_unlock();
+
+ ret = write_to_log(log_id, vec, nr);
+ errno = save_errno;
+ return ret;
+}
+
+LIBLOG_ABI_PUBLIC int __android_log_write(int prio, const char* tag, const char* msg) {
+ return __android_log_buf_write(LOG_ID_MAIN, prio, tag, msg);
+}
+
+LIBLOG_ABI_PUBLIC int __android_log_buf_write(int bufID, int prio, const char* tag,
+ const char* msg) {
+ struct iovec vec[3];
+ char tmp_tag[32];
+
+ if (!tag) tag = "";
+
+ /* XXX: This needs to go! */
+ if (bufID != LOG_ID_RADIO) {
+ switch (tag[0]) {
+ case 'H':
+ if (strcmp(tag + 1, "HTC_RIL" + 1)) break;
+ goto inform;
+ case 'R':
+ /* Any log tag with "RIL" as the prefix */
+ if (strncmp(tag + 1, "RIL" + 1, strlen("RIL") - 1)) break;
+ goto inform;
+ case 'Q':
+ /* Any log tag with "QC_RIL" as the prefix */
+ if (strncmp(tag + 1, "QC_RIL" + 1, strlen("QC_RIL") - 1)) break;
+ goto inform;
+ case 'I':
+ /* Any log tag with "IMS" as the prefix */
+ if (strncmp(tag + 1, "IMS" + 1, strlen("IMS") - 1)) break;
+ goto inform;
+ case 'A':
+ if (strcmp(tag + 1, "AT" + 1)) break;
+ goto inform;
+ case 'G':
+ if (strcmp(tag + 1, "GSM" + 1)) break;
+ goto inform;
+ case 'S':
+ if (strcmp(tag + 1, "STK" + 1) && strcmp(tag + 1, "SMS" + 1)) break;
+ goto inform;
+ case 'C':
+ if (strcmp(tag + 1, "CDMA" + 1)) break;
+ goto inform;
+ case 'P':
+ if (strcmp(tag + 1, "PHONE" + 1)) break;
+ /* FALLTHRU */
+ inform:
+ bufID = LOG_ID_RADIO;
+ snprintf(tmp_tag, sizeof(tmp_tag), "use-Rlog/RLOG-%s", tag);
+ tag = tmp_tag;
+ [[fallthrough]];
+ default:
+ break;
+ }
+ }
+
+#if __BIONIC__
+ if (prio == ANDROID_LOG_FATAL) {
+ android_set_abort_message(msg);
+ }
+#endif
+
+ vec[0].iov_base = (unsigned char*)&prio;
+ vec[0].iov_len = 1;
+ vec[1].iov_base = (void*)tag;
+ vec[1].iov_len = strlen(tag) + 1;
+ vec[2].iov_base = (void*)msg;
+ vec[2].iov_len = strlen(msg) + 1;
+
+ return write_to_log(static_cast<log_id_t>(bufID), vec, 3);
+}
+
+LIBLOG_ABI_PUBLIC int __android_log_vprint(int prio, const char* tag, const char* fmt, va_list ap) {
+ char buf[LOG_BUF_SIZE];
+
+ vsnprintf(buf, LOG_BUF_SIZE, fmt, ap);
+
+ return __android_log_write(prio, tag, buf);
+}
+
+LIBLOG_ABI_PUBLIC int __android_log_print(int prio, const char* tag, const char* fmt, ...) {
+ va_list ap;
+ char buf[LOG_BUF_SIZE];
+
+ va_start(ap, fmt);
+ vsnprintf(buf, LOG_BUF_SIZE, fmt, ap);
+ va_end(ap);
+
+ return __android_log_write(prio, tag, buf);
+}
+
+LIBLOG_ABI_PUBLIC int __android_log_buf_print(int bufID, int prio, const char* tag, const char* fmt,
+ ...) {
+ va_list ap;
+ char buf[LOG_BUF_SIZE];
+
+ va_start(ap, fmt);
+ vsnprintf(buf, LOG_BUF_SIZE, fmt, ap);
+ va_end(ap);
+
+ return __android_log_buf_write(bufID, prio, tag, buf);
+}
+
+LIBLOG_ABI_PUBLIC void __android_log_assert(const char* cond, const char* tag, const char* fmt,
+ ...) {
+ char buf[LOG_BUF_SIZE];
+
+ if (fmt) {
+ va_list ap;
+ va_start(ap, fmt);
+ vsnprintf(buf, LOG_BUF_SIZE, fmt, ap);
+ va_end(ap);
+ } else {
+ /* Msg not provided, log condition. N.B. Do not use cond directly as
+ * format string as it could contain spurious '%' syntax (e.g.
+ * "%d" in "blocks%devs == 0").
+ */
+ if (cond)
+ snprintf(buf, LOG_BUF_SIZE, "Assertion failed: %s", cond);
+ else
+ strcpy(buf, "Unspecified assertion failed");
+ }
+
+ // Log assertion failures to stderr for the benefit of "adb shell" users
+ // and gtests (http://b/23675822).
+ struct iovec iov[2] = {
+ {buf, strlen(buf)},
+ {(char*)"\n", 1},
+ };
+ TEMP_FAILURE_RETRY(writev(2, iov, 2));
+
+ __android_log_write(ANDROID_LOG_FATAL, tag, buf);
+ abort(); /* abort so we have a chance to debug the situation */
+ /* NOTREACHED */
+}
+
+LIBLOG_ABI_PUBLIC int __android_log_bwrite(int32_t tag, const void* payload, size_t len) {
+ struct iovec vec[2];
+
+ vec[0].iov_base = &tag;
+ vec[0].iov_len = sizeof(tag);
+ vec[1].iov_base = (void*)payload;
+ vec[1].iov_len = len;
+
+ return write_to_log(LOG_ID_EVENTS, vec, 2);
+}
+
+LIBLOG_ABI_PUBLIC int __android_log_stats_bwrite(int32_t tag, const void* payload, size_t len) {
+ struct iovec vec[2];
+
+ vec[0].iov_base = &tag;
+ vec[0].iov_len = sizeof(tag);
+ vec[1].iov_base = (void*)payload;
+ vec[1].iov_len = len;
+
+ return write_to_log(LOG_ID_STATS, vec, 2);
+}
+
+LIBLOG_ABI_PUBLIC int __android_log_security_bwrite(int32_t tag, const void* payload, size_t len) {
+ struct iovec vec[2];
+
+ vec[0].iov_base = &tag;
+ vec[0].iov_len = sizeof(tag);
+ vec[1].iov_base = (void*)payload;
+ vec[1].iov_len = len;
+
+ return write_to_log(LOG_ID_SECURITY, vec, 2);
+}
+
+/*
+ * Like __android_log_bwrite, but takes the type as well. Doesn't work
+ * for the general case where we're generating lists of stuff, but very
+ * handy if we just want to dump an integer into the log.
+ */
+LIBLOG_ABI_PUBLIC int __android_log_btwrite(int32_t tag, char type, const void* payload,
+ size_t len) {
+ struct iovec vec[3];
+
+ vec[0].iov_base = &tag;
+ vec[0].iov_len = sizeof(tag);
+ vec[1].iov_base = &type;
+ vec[1].iov_len = sizeof(type);
+ vec[2].iov_base = (void*)payload;
+ vec[2].iov_len = len;
+
+ return write_to_log(LOG_ID_EVENTS, vec, 3);
+}
+
+/*
+ * Like __android_log_bwrite, but used for writing strings to the
+ * event log.
+ */
+LIBLOG_ABI_PUBLIC int __android_log_bswrite(int32_t tag, const char* payload) {
+ struct iovec vec[4];
+ char type = EVENT_TYPE_STRING;
+ uint32_t len = strlen(payload);
+
+ vec[0].iov_base = &tag;
+ vec[0].iov_len = sizeof(tag);
+ vec[1].iov_base = &type;
+ vec[1].iov_len = sizeof(type);
+ vec[2].iov_base = &len;
+ vec[2].iov_len = sizeof(len);
+ vec[3].iov_base = (void*)payload;
+ vec[3].iov_len = len;
+
+ return write_to_log(LOG_ID_EVENTS, vec, 4);
+}
+
+/*
+ * Like __android_log_security_bwrite, but used for writing strings to the
+ * security log.
+ */
+LIBLOG_ABI_PUBLIC int __android_log_security_bswrite(int32_t tag, const char* payload) {
+ struct iovec vec[4];
+ char type = EVENT_TYPE_STRING;
+ uint32_t len = strlen(payload);
+
+ vec[0].iov_base = &tag;
+ vec[0].iov_len = sizeof(tag);
+ vec[1].iov_base = &type;
+ vec[1].iov_len = sizeof(type);
+ vec[2].iov_base = &len;
+ vec[2].iov_len = sizeof(len);
+ vec[3].iov_base = (void*)payload;
+ vec[3].iov_len = len;
+
+ return write_to_log(LOG_ID_SECURITY, vec, 4);
+}
+
+static int __write_to_log_null(log_id_t log_id, struct iovec* vec, size_t nr) {
+ size_t len, i;
+
+ if ((log_id < LOG_ID_MIN) || (log_id >= LOG_ID_MAX)) {
+ return -EINVAL;
+ }
+
+ for (len = i = 0; i < nr; ++i) {
+ len += vec[i].iov_len;
+ }
+ if (!len) {
+ return -EINVAL;
+ }
+ return len;
+}
+
+/* Following functions need access to our internal write_to_log status */
+
+LIBLOG_HIDDEN int __android_log_transport;
+
+LIBLOG_ABI_PUBLIC int android_set_log_transport(int transport_flag) {
+ int retval;
+
+ if (transport_flag < 0) {
+ return -EINVAL;
+ }
+
+ retval = LOGGER_NULL;
+
+ __android_log_lock();
+
+ if (transport_flag & LOGGER_NULL) {
+ write_to_log = __write_to_log_null;
+
+ __android_log_unlock();
+
+ return retval;
+ }
+
+ __android_log_transport &= LOGGER_LOGD | LOGGER_STDERR;
+
+ transport_flag &= LOGGER_LOGD | LOGGER_STDERR;
+
+ if (__android_log_transport != transport_flag) {
+ __android_log_transport = transport_flag;
+ __android_log_config_write_close();
+ __android_log_config_read_close();
+
+ write_to_log = __write_to_log_init;
+ /* generically we only expect these two values for write_to_log */
+ } else if ((write_to_log != __write_to_log_init) && (write_to_log != __write_to_log_daemon)) {
+ write_to_log = __write_to_log_init;
+ }
+
+ retval = __android_log_transport;
+
+ __android_log_unlock();
+
+ return retval;
+}
+
+LIBLOG_ABI_PUBLIC int android_get_log_transport() {
+ int ret = LOGGER_DEFAULT;
+
+ __android_log_lock();
+ if (write_to_log == __write_to_log_null) {
+ ret = LOGGER_NULL;
+ } else {
+ __android_log_transport &= LOGGER_LOGD | LOGGER_STDERR;
+ ret = __android_log_transport;
+ if ((write_to_log != __write_to_log_init) && (write_to_log != __write_to_log_daemon)) {
+ ret = -EINVAL;
+ }
+ }
+ __android_log_unlock();
+
+ return ret;
+}