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-rw-r--r--liblog/fake_log_device.c677
1 files changed, 677 insertions, 0 deletions
diff --git a/liblog/fake_log_device.c b/liblog/fake_log_device.c
new file mode 100644
index 0000000..d9d67b4
--- /dev/null
+++ b/liblog/fake_log_device.c
@@ -0,0 +1,677 @@
+/*
+ * Copyright (C) 2008 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.
+ */
+/*
+ * Intercepts log messages intended for the Android log device.
+ * When running in the context of the simulator, the messages are
+ * passed on to the underlying (fake) log device. When not in the
+ * simulator, messages are printed to stderr.
+ */
+#include "cutils/logd.h"
+
+#include <stdlib.h>
+#include <string.h>
+#include <ctype.h>
+#include <errno.h>
+#include <fcntl.h>
+
+#ifdef HAVE_PTHREADS
+#include <pthread.h>
+#endif
+
+#define kMaxTagLen 16 /* from the long-dead utils/Log.cpp */
+
+#define kTagSetSize 16 /* arbitrary */
+
+#if 0
+#define TRACE(...) printf("fake_log_device: " __VA_ARGS__)
+#else
+#define TRACE(...) ((void)0)
+#endif
+
+/* from the long-dead utils/Log.cpp */
+typedef enum {
+ FORMAT_OFF = 0,
+ FORMAT_BRIEF,
+ FORMAT_PROCESS,
+ FORMAT_TAG,
+ FORMAT_THREAD,
+ FORMAT_RAW,
+ FORMAT_TIME,
+ FORMAT_THREADTIME,
+ FORMAT_LONG
+} LogFormat;
+
+
+/*
+ * Log driver state.
+ */
+typedef struct LogState {
+ /* the fake fd that's seen by the user */
+ int fakeFd;
+
+ /* a printable name for this fake device */
+ char *debugName;
+
+ /* nonzero if this is a binary log */
+ int isBinary;
+
+ /* global minimum priority */
+ int globalMinPriority;
+
+ /* output format */
+ LogFormat outputFormat;
+
+ /* tags and priorities */
+ struct {
+ char tag[kMaxTagLen];
+ int minPriority;
+ } tagSet[kTagSetSize];
+} LogState;
+
+
+#ifdef HAVE_PTHREADS
+/*
+ * Locking. Since we're emulating a device, we need to be prepared
+ * to have multiple callers at the same time. This lock is used
+ * to both protect the fd list and to prevent LogStates from being
+ * freed out from under a user.
+ */
+static pthread_mutex_t fakeLogDeviceLock = PTHREAD_MUTEX_INITIALIZER;
+
+static void lock()
+{
+ pthread_mutex_lock(&fakeLogDeviceLock);
+}
+
+static void unlock()
+{
+ pthread_mutex_unlock(&fakeLogDeviceLock);
+}
+#else // !HAVE_PTHREADS
+#define lock() ((void)0)
+#define unlock() ((void)0)
+#endif // !HAVE_PTHREADS
+
+
+/*
+ * File descriptor management.
+ */
+#define FAKE_FD_BASE 10000
+#define MAX_OPEN_LOGS 16
+static LogState *openLogTable[MAX_OPEN_LOGS];
+
+/*
+ * Allocate an fd and associate a new LogState with it.
+ * The fd is available via the fakeFd field of the return value.
+ */
+static LogState *createLogState()
+{
+ size_t i;
+
+ for (i = 0; i < sizeof(openLogTable); i++) {
+ if (openLogTable[i] == NULL) {
+ openLogTable[i] = calloc(1, sizeof(LogState));
+ openLogTable[i]->fakeFd = FAKE_FD_BASE + i;
+ return openLogTable[i];
+ }
+ }
+ return NULL;
+}
+
+/*
+ * Translate an fd to a LogState.
+ */
+static LogState *fdToLogState(int fd)
+{
+ if (fd >= FAKE_FD_BASE && fd < FAKE_FD_BASE + MAX_OPEN_LOGS) {
+ return openLogTable[fd - FAKE_FD_BASE];
+ }
+ return NULL;
+}
+
+/*
+ * Unregister the fake fd and free the memory it pointed to.
+ */
+static void deleteFakeFd(int fd)
+{
+ LogState *ls;
+
+ lock();
+
+ ls = fdToLogState(fd);
+ if (ls != NULL) {
+ openLogTable[fd - FAKE_FD_BASE] = NULL;
+ free(ls->debugName);
+ free(ls);
+ }
+
+ unlock();
+}
+
+/*
+ * Configure logging based on ANDROID_LOG_TAGS environment variable. We
+ * need to parse a string that looks like
+ *
+ * *:v jdwp:d dalvikvm:d dalvikvm-gc:i dalvikvmi:i
+ *
+ * The tag (or '*' for the global level) comes first, followed by a colon
+ * and a letter indicating the minimum priority level we're expected to log.
+ * This can be used to reveal or conceal logs with specific tags.
+ *
+ * We also want to check ANDROID_PRINTF_LOG to determine how the output
+ * will look.
+ */
+static void configureInitialState(const char* pathName, LogState* logState)
+{
+ static const int kDevLogLen = sizeof("/dev/log/") - 1;
+
+ logState->debugName = strdup(pathName);
+
+ /* identify binary logs */
+ if (strcmp(pathName + kDevLogLen, "events") == 0) {
+ logState->isBinary = 1;
+ }
+
+ /* global min priority defaults to "info" level */
+ logState->globalMinPriority = ANDROID_LOG_INFO;
+
+ /*
+ * This is based on the the long-dead utils/Log.cpp code.
+ */
+ const char* tags = getenv("ANDROID_LOG_TAGS");
+ TRACE("Found ANDROID_LOG_TAGS='%s'\n", tags);
+ if (tags != NULL) {
+ int entry = 0;
+
+ while (*tags != '\0') {
+ char tagName[kMaxTagLen];
+ int i, minPrio;
+
+ while (isspace(*tags))
+ tags++;
+
+ i = 0;
+ while (*tags != '\0' && !isspace(*tags) && *tags != ':' &&
+ i < kMaxTagLen)
+ {
+ tagName[i++] = *tags++;
+ }
+ if (i == kMaxTagLen) {
+ TRACE("ERROR: env tag too long (%d chars max)\n", kMaxTagLen-1);
+ return;
+ }
+ tagName[i] = '\0';
+
+ /* default priority, if there's no ":" part; also zero out '*' */
+ minPrio = ANDROID_LOG_VERBOSE;
+ if (tagName[0] == '*' && tagName[1] == '\0') {
+ minPrio = ANDROID_LOG_DEBUG;
+ tagName[0] = '\0';
+ }
+
+ if (*tags == ':') {
+ tags++;
+ if (*tags >= '0' && *tags <= '9') {
+ if (*tags >= ('0' + ANDROID_LOG_SILENT))
+ minPrio = ANDROID_LOG_VERBOSE;
+ else
+ minPrio = *tags - '\0';
+ } else {
+ switch (*tags) {
+ case 'v': minPrio = ANDROID_LOG_VERBOSE; break;
+ case 'd': minPrio = ANDROID_LOG_DEBUG; break;
+ case 'i': minPrio = ANDROID_LOG_INFO; break;
+ case 'w': minPrio = ANDROID_LOG_WARN; break;
+ case 'e': minPrio = ANDROID_LOG_ERROR; break;
+ case 'f': minPrio = ANDROID_LOG_FATAL; break;
+ case 's': minPrio = ANDROID_LOG_SILENT; break;
+ default: minPrio = ANDROID_LOG_DEFAULT; break;
+ }
+ }
+
+ tags++;
+ if (*tags != '\0' && !isspace(*tags)) {
+ TRACE("ERROR: garbage in tag env; expected whitespace\n");
+ TRACE(" env='%s'\n", tags);
+ return;
+ }
+ }
+
+ if (tagName[0] == 0) {
+ logState->globalMinPriority = minPrio;
+ TRACE("+++ global min prio %d\n", logState->globalMinPriority);
+ } else {
+ logState->tagSet[entry].minPriority = minPrio;
+ strcpy(logState->tagSet[entry].tag, tagName);
+ TRACE("+++ entry %d: %s:%d\n",
+ entry,
+ logState->tagSet[entry].tag,
+ logState->tagSet[entry].minPriority);
+ entry++;
+ }
+ }
+ }
+
+
+ /*
+ * Taken from the long-dead utils/Log.cpp
+ */
+ const char* fstr = getenv("ANDROID_PRINTF_LOG");
+ LogFormat format;
+ if (fstr == NULL) {
+ format = FORMAT_BRIEF;
+ } else {
+ if (strcmp(fstr, "brief") == 0)
+ format = FORMAT_BRIEF;
+ else if (strcmp(fstr, "process") == 0)
+ format = FORMAT_PROCESS;
+ else if (strcmp(fstr, "tag") == 0)
+ format = FORMAT_PROCESS;
+ else if (strcmp(fstr, "thread") == 0)
+ format = FORMAT_PROCESS;
+ else if (strcmp(fstr, "raw") == 0)
+ format = FORMAT_PROCESS;
+ else if (strcmp(fstr, "time") == 0)
+ format = FORMAT_PROCESS;
+ else if (strcmp(fstr, "long") == 0)
+ format = FORMAT_PROCESS;
+ else
+ format = (LogFormat) atoi(fstr); // really?!
+ }
+
+ logState->outputFormat = format;
+}
+
+/*
+ * Return a human-readable string for the priority level. Always returns
+ * a valid string.
+ */
+static const char* getPriorityString(int priority)
+{
+ /* the first character of each string should be unique */
+ static const char* priorityStrings[] = {
+ "Verbose", "Debug", "Info", "Warn", "Error", "Assert"
+ };
+ int idx;
+
+ idx = (int) priority - (int) ANDROID_LOG_VERBOSE;
+ if (idx < 0 ||
+ idx >= (int) (sizeof(priorityStrings) / sizeof(priorityStrings[0])))
+ return "?unknown?";
+ return priorityStrings[idx];
+}
+
+#ifndef HAVE_WRITEV
+/*
+ * Some platforms like WIN32 do not have writev().
+ * Make up something to replace it.
+ */
+static ssize_t fake_writev(int fd, const struct iovec *iov, int iovcnt) {
+ int result = 0;
+ struct iovec* end = iov + iovcnt;
+ for (; iov < end; iov++) {
+ int w = write(fd, iov->iov_base, iov->iov_len);
+ if (w != iov->iov_len) {
+ if (w < 0)
+ return w;
+ return result + w;
+ }
+ result += w;
+ }
+ return result;
+}
+
+#define writev fake_writev
+#endif
+
+
+/*
+ * Write a filtered log message to stderr.
+ *
+ * Log format parsing taken from the long-dead utils/Log.cpp.
+ */
+static void showLog(LogState *state,
+ int logPrio, const char* tag, const char* msg)
+{
+#if defined(HAVE_LOCALTIME_R)
+ struct tm tmBuf;
+#endif
+ struct tm* ptm;
+ char timeBuf[32];
+ char prefixBuf[128], suffixBuf[128];
+ char priChar;
+ time_t when;
+ pid_t pid, tid;
+
+ TRACE("LOG %d: %s %s", logPrio, tag, msg);
+
+ priChar = getPriorityString(logPrio)[0];
+ when = time(NULL);
+ pid = tid = getpid(); // find gettid()?
+
+ /*
+ * Get the current date/time in pretty form
+ *
+ * It's often useful when examining a log with "less" to jump to
+ * a specific point in the file by searching for the date/time stamp.
+ * For this reason it's very annoying to have regexp meta characters
+ * in the time stamp. Don't use forward slashes, parenthesis,
+ * brackets, asterisks, or other special chars here.
+ */
+#if defined(HAVE_LOCALTIME_R)
+ ptm = localtime_r(&when, &tmBuf);
+#else
+ ptm = localtime(&when);
+#endif
+ //strftime(timeBuf, sizeof(timeBuf), "%Y-%m-%d %H:%M:%S", ptm);
+ strftime(timeBuf, sizeof(timeBuf), "%m-%d %H:%M:%S", ptm);
+
+ /*
+ * Construct a buffer containing the log header and log message.
+ */
+ size_t prefixLen, suffixLen;
+
+ switch (state->outputFormat) {
+ case FORMAT_TAG:
+ prefixLen = snprintf(prefixBuf, sizeof(prefixBuf),
+ "%c/%-8s: ", priChar, tag);
+ strcpy(suffixBuf, "\n"); suffixLen = 1;
+ break;
+ case FORMAT_PROCESS:
+ prefixLen = snprintf(prefixBuf, sizeof(prefixBuf),
+ "%c(%5d) ", priChar, pid);
+ suffixLen = snprintf(suffixBuf, sizeof(suffixBuf),
+ " (%s)\n", tag);
+ break;
+ case FORMAT_THREAD:
+ prefixLen = snprintf(prefixBuf, sizeof(prefixBuf),
+ "%c(%5d:%p) ", priChar, pid, (void*)tid);
+ strcpy(suffixBuf, "\n"); suffixLen = 1;
+ break;
+ case FORMAT_RAW:
+ prefixBuf[0] = 0; prefixLen = 0;
+ strcpy(suffixBuf, "\n"); suffixLen = 1;
+ break;
+ case FORMAT_TIME:
+ prefixLen = snprintf(prefixBuf, sizeof(prefixBuf),
+ "%s %-8s\n\t", timeBuf, tag);
+ strcpy(suffixBuf, "\n"); suffixLen = 1;
+ break;
+ case FORMAT_THREADTIME:
+ prefixLen = snprintf(prefixBuf, sizeof(prefixBuf),
+ "%s %5d %5d %c %-8s \n\t", timeBuf, pid, tid, priChar, tag);
+ strcpy(suffixBuf, "\n"); suffixLen = 1;
+ break;
+ case FORMAT_LONG:
+ prefixLen = snprintf(prefixBuf, sizeof(prefixBuf),
+ "[ %s %5d:%p %c/%-8s ]\n",
+ timeBuf, pid, (void*)tid, priChar, tag);
+ strcpy(suffixBuf, "\n\n"); suffixLen = 2;
+ break;
+ default:
+ prefixLen = snprintf(prefixBuf, sizeof(prefixBuf),
+ "%c/%-8s(%5d): ", priChar, tag, pid);
+ strcpy(suffixBuf, "\n"); suffixLen = 1;
+ break;
+ }
+
+ /*
+ * Figure out how many lines there will be.
+ */
+ const char* end = msg + strlen(msg);
+ size_t numLines = 0;
+ const char* p = msg;
+ while (p < end) {
+ if (*p++ == '\n') numLines++;
+ }
+ if (p > msg && *(p-1) != '\n') numLines++;
+
+ /*
+ * Create an array of iovecs large enough to write all of
+ * the lines with a prefix and a suffix.
+ */
+ const size_t INLINE_VECS = 6;
+ struct iovec stackVec[INLINE_VECS];
+ struct iovec* vec = stackVec;
+
+ numLines *= 3; // 3 iovecs per line.
+ if (numLines > INLINE_VECS) {
+ vec = (struct iovec*)malloc(sizeof(struct iovec)*numLines);
+ if (vec == NULL) {
+ msg = "LOG: write failed, no memory";
+ numLines = 3;
+ }
+ }
+
+ /*
+ * Fill in the iovec pointers.
+ */
+ p = msg;
+ struct iovec* v = vec;
+ int totalLen = 0;
+ while (p < end) {
+ if (prefixLen > 0) {
+ v->iov_base = prefixBuf;
+ v->iov_len = prefixLen;
+ totalLen += prefixLen;
+ v++;
+ }
+ const char* start = p;
+ while (p < end && *p != '\n') p++;
+ if ((p-start) > 0) {
+ v->iov_base = (void*)start;
+ v->iov_len = p-start;
+ totalLen += p-start;
+ v++;
+ }
+ if (*p == '\n') p++;
+ if (suffixLen > 0) {
+ v->iov_base = suffixBuf;
+ v->iov_len = suffixLen;
+ totalLen += suffixLen;
+ v++;
+ }
+ }
+
+ /*
+ * Write the entire message to the log file with a single writev() call.
+ * We need to use this rather than a collection of printf()s on a FILE*
+ * because of multi-threading and multi-process issues.
+ *
+ * If the file was not opened with O_APPEND, this will produce interleaved
+ * output when called on the same file from multiple processes.
+ *
+ * If the file descriptor is actually a network socket, the writev()
+ * call may return with a partial write. Putting the writev() call in
+ * a loop can result in interleaved data. This can be alleviated
+ * somewhat by wrapping the writev call in the Mutex.
+ */
+
+ for(;;) {
+ int cc = writev(fileno(stderr), vec, v-vec);
+
+ if (cc == totalLen) break;
+
+ if (cc < 0) {
+ if(errno == EINTR) continue;
+
+ /* can't really log the failure; for now, throw out a stderr */
+ fprintf(stderr, "+++ LOG: write failed (errno=%d)\n", errno);
+ break;
+ } else {
+ /* shouldn't happen when writing to file or tty */
+ fprintf(stderr, "+++ LOG: write partial (%d of %d)\n", cc, totalLen);
+ break;
+ }
+ }
+
+ /* if we allocated storage for the iovecs, free it */
+ if (vec != stackVec)
+ free(vec);
+}
+
+
+/*
+ * Receive a log message. We happen to know that "vector" has three parts:
+ *
+ * priority (1 byte)
+ * tag (N bytes -- null-terminated ASCII string)
+ * message (N bytes -- null-terminated ASCII string)
+ */
+static ssize_t logWritev(int fd, const struct iovec* vector, int count)
+{
+ LogState* state;
+
+ /* Make sure that no-one frees the LogState while we're using it.
+ * Also guarantees that only one thread is in showLog() at a given
+ * time (if it matters).
+ */
+ lock();
+
+ state = fdToLogState(fd);
+ if (state == NULL) {
+ errno = EBADF;
+ goto error;
+ }
+
+ if (state->isBinary) {
+ TRACE("%s: ignoring binary log\n", state->debugName);
+ goto bail;
+ }
+
+ if (count != 3) {
+ TRACE("%s: writevLog with count=%d not expected\n",
+ state->debugName, count);
+ goto error;
+ }
+
+ /* pull out the three fields */
+ int logPrio = *(const char*)vector[0].iov_base;
+ const char* tag = (const char*) vector[1].iov_base;
+ const char* msg = (const char*) vector[2].iov_base;
+
+ /* see if this log tag is configured */
+ int i;
+ int minPrio = state->globalMinPriority;
+ for (i = 0; i < kTagSetSize; i++) {
+ if (state->tagSet[i].minPriority == ANDROID_LOG_UNKNOWN)
+ break; /* reached end of configured values */
+
+ if (strcmp(state->tagSet[i].tag, tag) == 0) {
+ //TRACE("MATCH tag '%s'\n", tag);
+ minPrio = state->tagSet[i].minPriority;
+ break;
+ }
+ }
+
+ if (logPrio >= minPrio) {
+ showLog(state, logPrio, tag, msg);
+ } else {
+ //TRACE("+++ NOLOG(%d): %s %s", logPrio, tag, msg);
+ }
+
+bail:
+ unlock();
+ return vector[0].iov_len + vector[1].iov_len + vector[2].iov_len;
+error:
+ unlock();
+ return -1;
+}
+
+/*
+ * Free up our state and close the fake descriptor.
+ */
+static int logClose(int fd)
+{
+ deleteFakeFd(fd);
+ return 0;
+}
+
+/*
+ * Open a log output device and return a fake fd.
+ */
+static int logOpen(const char* pathName, int flags)
+{
+ LogState *logState;
+ int fd = -1;
+
+ lock();
+
+ logState = createLogState();
+ if (logState != NULL) {
+ configureInitialState(pathName, logState);
+ fd = logState->fakeFd;
+ } else {
+ errno = ENFILE;
+ }
+
+ unlock();
+
+ return fd;
+}
+
+
+/*
+ * Runtime redirection. If this binary is running in the simulator,
+ * just pass log messages to the emulated device. If it's running
+ * outside of the simulator, write the log messages to stderr.
+ */
+
+static int (*redirectOpen)(const char *pathName, int flags) = NULL;
+static int (*redirectClose)(int fd) = NULL;
+static ssize_t (*redirectWritev)(int fd, const struct iovec* vector, int count)
+ = NULL;
+
+static void setRedirects()
+{
+ const char *ws;
+
+ /* Wrapsim sets this environment variable on children that it's
+ * created using its LD_PRELOAD wrapper.
+ */
+ ws = getenv("ANDROID_WRAPSIM");
+ if (ws != NULL && strcmp(ws, "1") == 0) {
+ /* We're running inside wrapsim, so we can just write to the device. */
+ redirectOpen = (int (*)(const char *pathName, int flags))open;
+ redirectClose = close;
+ redirectWritev = writev;
+ } else {
+ /* There's no device to delegate to; handle the logging ourselves. */
+ redirectOpen = logOpen;
+ redirectClose = logClose;
+ redirectWritev = logWritev;
+ }
+}
+
+int fakeLogOpen(const char *pathName, int flags)
+{
+ if (redirectOpen == NULL) {
+ setRedirects();
+ }
+ return redirectOpen(pathName, flags);
+}
+
+int fakeLogClose(int fd)
+{
+ /* Assume that open() was called first. */
+ return redirectClose(fd);
+}
+
+ssize_t fakeLogWritev(int fd, const struct iovec* vector, int count)
+{
+ /* Assume that open() was called first. */
+ return redirectWritev(fd, vector, count);
+}
generated by cgit v1.1 at 2024-10-31 00:16:09 +0000