liblog: simplify logd 'command' functions and struct logger
There are a set of functions, such as android_logger_get_log_size()
and android_logger_get_prune_list() that talk to the logd command
socket to perform their activities. There's a transport abstraction
layer that handles these symbols to optionally route them to other
transports, originally designed for pstore or local logger; however
these functions fundamentally only make sense for logd.
Ideally, these functions would be removed and new functions would be
added that do not depend on struct logger_list or struct logger and
more clearly indicate that they only work with logd. For example:
android_logger_get_size(struct logger*) could be
logd_get_buffer_size(log_id_t log_id). We would remove the need to
'open' the struct logger and make it clear that it only operates on
logd.
Since liblog is an llndk library however, we cannot change or remove
these symbols. Since these symbols are not frequently used, it seems
acceptable to keep them as is and not introduce improved versions.
We, however, do want to simplify the code that handles them and this
change removes the transport abstraction layer that handles them.
They retain the behavior that unless the struct logger_list was opened
for logd, that the functions return -EINVAL.
The one exception to this is android_logger_clear(). If the struct
logger provided to this function was opened from a struct logger_list
that used pstore for its mode argument, this function will clear the
entire pstore log. This function does not respect the 'logId'
parameter of the struct logger, since that would not be possible.
This change removes this android_logger_clear() behavior and makes it
strictly for logd, for symmetry with the rest of the functions and due
to the lack of clarity regarding the 'logId' parameter of its input.
The only caller of this function, logcat, will clear pstore directly.
struct logger was built to encapsulate the information needed to
connect to a logger device from the old kernel logger. Now that we
only support reading from pstore and from logd, there is much less
information needed to be captured. Specifically, we only need to know
the log_id and whether or not it was opened as part of a pstore or
logd 'list'.
Test: liblog-unit-test
Test: logcat -c/-g/-G/-p/-P/-S work
Test: logcat -c works with -L
Test: logcat -g/-G/-p/-P/-S continue to fail with -L
Change-Id: I2c549b6f8539de94510e223949ab209ecc40e2d0
diff --git a/liblog/logger_read.cpp b/liblog/logger_read.cpp
index 5e10ada..79b40a9 100644
--- a/liblog/logger_read.cpp
+++ b/liblog/logger_read.cpp
@@ -21,6 +21,7 @@
#include <pthread.h>
#include <sched.h>
#include <stddef.h>
+#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
@@ -32,211 +33,53 @@
#include "log_portability.h"
#include "logger.h"
-/* android_logger_alloc unimplemented, no use case */
-/* android_logger_free not exported */
-static void android_logger_free(struct logger* logger) {
- if (!logger) {
- return;
- }
-
- list_remove(&logger->node);
-
- free(logger);
-}
-
-/* android_logger_alloc unimplemented, no use case */
-
/* method for getting the associated sublog id */
log_id_t android_logger_get_id(struct logger* logger) {
- return ((struct logger*)logger)->logId;
+ return static_cast<log_id_t>(reinterpret_cast<uintptr_t>(logger) & LOGGER_LOG_ID_MASK);
}
-static int init_transport_context(struct logger_list* logger_list) {
+static struct logger_list* android_logger_list_alloc_internal(int mode, unsigned int tail,
+ log_time start, pid_t pid) {
+ auto* logger_list = static_cast<struct logger_list*>(calloc(1, sizeof(struct logger_list)));
if (!logger_list) {
- return -EINVAL;
+ return nullptr;
}
- if (list_empty(&logger_list->logger)) {
- return -EINVAL;
- }
-
- if (logger_list->transport_initialized) {
- return 0;
- }
+ logger_list->mode = mode;
+ logger_list->start = start;
+ logger_list->tail = tail;
+ logger_list->pid = pid;
#if (FAKE_LOG_DEVICE == 0)
extern struct android_log_transport_read logdLoggerRead;
extern struct android_log_transport_read pmsgLoggerRead;
- struct android_log_transport_read* transport;
- transport = (logger_list->mode & ANDROID_LOG_PSTORE) ? &pmsgLoggerRead : &logdLoggerRead;
-
- struct logger* logger;
- unsigned logMask = 0;
-
- logger_for_each(logger, logger_list) {
- log_id_t logId = logger->logId;
-
- if (logId == LOG_ID_SECURITY && __android_log_uid() != AID_SYSTEM) {
- continue;
- }
- if (transport->read && (!transport->available || transport->available(logId) >= 0)) {
- logMask |= 1 << logId;
- }
- }
- if (!logMask) {
- return -ENODEV;
- }
-
- logger_list->transport_context.transport = transport;
- logger_list->transport_context.logMask = logMask;
+ logger_list->transport_context.transport =
+ (mode & ANDROID_LOG_PSTORE) ? &pmsgLoggerRead : &logdLoggerRead;
#endif
- return 0;
-}
-#define LOGGER_FUNCTION(logger, def, func, args...) \
- ssize_t ret = -EINVAL; \
- \
- if (!logger) { \
- return ret; \
- } \
- ret = init_transport_context(logger->parent); \
- if (ret < 0) { \
- return ret; \
- } \
- \
- ret = (def); \
- android_log_transport_context* transport_context = &logger->parent->transport_context; \
- if (transport_context->logMask & (1 << logger->logId) && transport_context->transport && \
- transport_context->transport->func) { \
- ssize_t retval = (transport_context->transport->func)(logger, transport_context, ##args); \
- if (ret >= 0 || ret == (def)) { \
- ret = retval; \
- } \
- } \
- return ret
-
-int android_logger_clear(struct logger* logger) {
- LOGGER_FUNCTION(logger, -ENODEV, clear);
-}
-
-/* returns the total size of the log's ring buffer */
-long android_logger_get_log_size(struct logger* logger) {
- LOGGER_FUNCTION(logger, -ENODEV, getSize);
-}
-
-int android_logger_set_log_size(struct logger* logger, unsigned long size) {
- LOGGER_FUNCTION(logger, -ENODEV, setSize, size);
-}
-
-/*
- * returns the readable size of the log's ring buffer (that is, amount of the
- * log consumed)
- */
-long android_logger_get_log_readable_size(struct logger* logger) {
- LOGGER_FUNCTION(logger, -ENODEV, getReadableSize);
-}
-
-/*
- * returns the logger version
- */
-int android_logger_get_log_version(struct logger* logger) {
- LOGGER_FUNCTION(logger, 4, version);
-}
-
-#define LOGGER_LIST_FUNCTION(logger_list, def, func, args...) \
- ssize_t ret = init_transport_context(logger_list); \
- if (ret < 0) { \
- return ret; \
- } \
- \
- ret = (def); \
- android_log_transport_context* transport_context = &logger_list->transport_context; \
- if (transport_context->transport && transport_context->transport->func) { \
- ssize_t retval = (transport_context->transport->func)(logger_list, transport_context, ##args); \
- if (ret >= 0 || ret == (def)) { \
- ret = retval; \
- } \
- } \
- return ret
-
-/*
- * returns statistics
- */
-ssize_t android_logger_get_statistics(struct logger_list* logger_list, char* buf, size_t len) {
- LOGGER_LIST_FUNCTION(logger_list, -ENODEV, getStats, buf, len);
-}
-
-ssize_t android_logger_get_prune_list(struct logger_list* logger_list, char* buf, size_t len) {
- LOGGER_LIST_FUNCTION(logger_list, -ENODEV, getPrune, buf, len);
-}
-
-int android_logger_set_prune_list(struct logger_list* logger_list, char* buf, size_t len) {
- LOGGER_LIST_FUNCTION(logger_list, -ENODEV, setPrune, buf, len);
+ return logger_list;
}
struct logger_list* android_logger_list_alloc(int mode, unsigned int tail, pid_t pid) {
- struct logger_list* logger_list;
-
- logger_list = static_cast<struct logger_list*>(calloc(1, sizeof(*logger_list)));
- if (!logger_list) {
- return NULL;
- }
-
- list_init(&logger_list->logger);
- logger_list->mode = mode;
- logger_list->tail = tail;
- logger_list->pid = pid;
-
- return logger_list;
+ return android_logger_list_alloc_internal(mode, tail, log_time(0, 0), pid);
}
struct logger_list* android_logger_list_alloc_time(int mode, log_time start, pid_t pid) {
- struct logger_list* logger_list;
-
- logger_list = static_cast<struct logger_list*>(calloc(1, sizeof(*logger_list)));
- if (!logger_list) {
- return NULL;
- }
-
- list_init(&logger_list->logger);
- logger_list->mode = mode;
- logger_list->start = start;
- logger_list->pid = pid;
-
- return logger_list;
+ return android_logger_list_alloc_internal(mode, 0, start, pid);
}
-/* android_logger_list_register unimplemented, no use case */
-/* android_logger_list_unregister unimplemented, no use case */
-
/* Open the named log and add it to the logger list */
struct logger* android_logger_open(struct logger_list* logger_list, log_id_t logId) {
- struct logger* logger;
-
if (!logger_list || (logId >= LOG_ID_MAX)) {
return nullptr;
}
- logger_for_each(logger, logger_list) {
- if (logger->logId == logId) {
- return reinterpret_cast<struct logger*>(logger);
- }
- }
+ logger_list->log_mask |= 1 << logId;
- logger = static_cast<struct logger*>(calloc(1, sizeof(*logger)));
- if (!logger) {
- return nullptr;
- }
-
- logger->logId = logId;
- list_add_tail(&logger_list->logger, &logger->node);
- logger->parent = logger_list;
-
- // Reset known transport to re-evaluate, since we added a new logger.
- logger_list->transport_initialized = false;
-
- return logger;
+ uintptr_t logger = logId;
+ logger |= (logger_list->mode & ANDROID_LOG_PSTORE) ? LOGGER_PMSG : LOGGER_LOGD;
+ return reinterpret_cast<struct logger*>(logger);
}
/* Open the single named log and make it part of a new logger list */
@@ -256,10 +99,14 @@
return logger_list;
}
-/* Validate log_msg packet, read function has already been null checked */
-static int android_transport_read(struct logger_list* logger_list,
- struct android_log_transport_context* transp,
- struct log_msg* log_msg) {
+int android_logger_list_read(struct logger_list* logger_list, struct log_msg* log_msg) {
+ if (logger_list == nullptr || logger_list->transport_context.transport == nullptr ||
+ logger_list->log_mask == 0) {
+ return -EINVAL;
+ }
+
+ android_log_transport_context* transp = &logger_list->transport_context;
+
int ret = (*transp->transport->read)(logger_list, transp, log_msg);
if (ret < 0) {
@@ -285,17 +132,6 @@
return ret;
}
-/* Read from the selected logs */
-int android_logger_list_read(struct logger_list* logger_list, struct log_msg* log_msg) {
- int ret = init_transport_context(logger_list);
- if (ret < 0) {
- return ret;
- }
-
- android_log_transport_context* transport_context = &logger_list->transport_context;
- return android_transport_read(logger_list, transport_context, log_msg);
-}
-
/* Close all the logs */
void android_logger_list_free(struct logger_list* logger_list) {
if (logger_list == NULL) {
@@ -308,11 +144,5 @@
(*transport_context->transport->close)(logger_list, transport_context);
}
- while (!list_empty(&logger_list->logger)) {
- struct listnode* node = list_head(&logger_list->logger);
- struct logger* logger = node_to_item(node, struct logger, node);
- android_logger_free((struct logger*)logger);
- }
-
free(logger_list);
}