1 /*
2  * Copyright (C) 2006-2017 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #include "logcat.h"
18 
19 #include <android-base/macros.h>
20 #include <arpa/inet.h>
21 #include <assert.h>
22 #include <ctype.h>
23 #include <dirent.h>
24 #include <errno.h>
25 #include <fcntl.h>
26 #include <getopt.h>
27 #include <math.h>
28 #include <pthread.h>
29 #include <sched.h>
30 #include <stdarg.h>
31 #include <stdio.h>
32 #include <stdlib.h>
33 #include <string.h>
34 #include <sys/cdefs.h>
35 #include <sys/ioctl.h>
36 #include <sys/resource.h>
37 #include <sys/socket.h>
38 #include <sys/stat.h>
39 #include <sys/types.h>
40 #include <time.h>
41 #include <unistd.h>
42 
43 #include <atomic>
44 #include <memory>
45 #include <regex>
46 #include <string>
47 #include <utility>
48 #include <vector>
49 
50 #include <android-base/file.h>
51 #include <android-base/properties.h>
52 #include <android-base/stringprintf.h>
53 #include <android-base/strings.h>
54 #include <cutils/sockets.h>
55 #include <log/event_tag_map.h>
56 #include <log/logprint.h>
57 #include <private/android_logger.h>
58 #include <processgroup/sched_policy.h>
59 #include <system/thread_defs.h>
60 
61 #define DEFAULT_MAX_ROTATED_LOGS 4
62 
63 struct log_device_t {
64     const char* device;
65     bool binary;
66     struct logger* logger;
67     struct logger_list* logger_list;
68     bool printed;
69 
70     log_device_t* next;
71 
log_device_tlog_device_t72     log_device_t(const char* d, bool b) {
73         device = d;
74         binary = b;
75         next = nullptr;
76         printed = false;
77         logger = nullptr;
78         logger_list = nullptr;
79     }
80 };
81 
82 struct android_logcat_context_internal {
83     // status
84     volatile std::atomic_int retval;  // valid if thread_stopped set
85     // Arguments passed in, or copies and storage thereof if a thread.
86     int argc;
87     char* const* argv;
88     char* const* envp;
89     std::vector<std::string> args;
90     std::vector<const char*> argv_hold;
91     std::vector<std::string> envs;
92     std::vector<const char*> envp_hold;
93     int output_fd;  // duplication of fileno(output) (below)
94     int error_fd;   // duplication of fileno(error) (below)
95 
96     // library
97     int fds[2];    // From popen call
98     FILE* output;  // everything writes to fileno(output), buffer unused
99     FILE* error;   // unless error == output.
100     pthread_t thr;
101     volatile std::atomic_bool stop;  // quick exit flag
102     volatile std::atomic_bool thread_stopped;
103     bool stderr_null;    // shell "2>/dev/null"
104     bool stderr_stdout;  // shell "2>&1"
105 
106     // global variables
107     AndroidLogFormat* logformat;
108     const char* outputFileName;
109     // 0 means "no log rotation"
110     size_t logRotateSizeKBytes;
111     // 0 means "unbounded"
112     size_t maxRotatedLogs;
113     size_t outByteCount;
114     int printBinary;
115     int devCount;  // >1 means multiple
116     std::unique_ptr<std::regex> regex;
117     log_device_t* devices;
118     EventTagMap* eventTagMap;
119     // 0 means "infinite"
120     size_t maxCount;
121     size_t printCount;
122 
123     bool printItAnyways;
124     bool debug;
125     bool hasOpenedEventTagMap;
126 };
127 
128 // Creates a context associated with this logcat instance
create_android_logcat()129 android_logcat_context create_android_logcat() {
130     android_logcat_context_internal* context;
131 
132     context = (android_logcat_context_internal*)calloc(
133         1, sizeof(android_logcat_context_internal));
134     if (!context) return nullptr;
135 
136     context->fds[0] = -1;
137     context->fds[1] = -1;
138     context->output_fd = -1;
139     context->error_fd = -1;
140     context->maxRotatedLogs = DEFAULT_MAX_ROTATED_LOGS;
141 
142     context->argv_hold.clear();
143     context->args.clear();
144     context->envp_hold.clear();
145     context->envs.clear();
146 
147     return (android_logcat_context)context;
148 }
149 
150 // logd prefixes records with a length field
151 #define RECORD_LENGTH_FIELD_SIZE_BYTES sizeof(uint32_t)
152 
153 namespace android {
154 
155 enum helpType { HELP_FALSE, HELP_TRUE, HELP_FORMAT };
156 
157 // if showHelp is set, newline required in fmt statement to transition to usage
158 static void logcat_panic(android_logcat_context_internal* context,
159                          enum helpType showHelp, const char* fmt, ...)
160     __printflike(3, 4);
161 
162 #ifndef F2FS_IOC_SET_PIN_FILE
163 #define F2FS_IOCTL_MAGIC       0xf5
164 #define F2FS_IOC_SET_PIN_FILE _IOW(F2FS_IOCTL_MAGIC, 13, __u32)
165 #endif
166 
openLogFile(const char * pathname,size_t sizeKB)167 static int openLogFile(const char* pathname, size_t sizeKB) {
168     int fd = open(pathname, O_WRONLY | O_APPEND | O_CREAT, S_IRUSR | S_IWUSR);
169     if (fd < 0) {
170         return fd;
171     }
172 
173     // no need to check errors
174     __u32 set = 1;
175     ioctl(fd, F2FS_IOC_SET_PIN_FILE, &set);
176     fallocate(fd, FALLOC_FL_KEEP_SIZE, 0, (sizeKB << 10));
177     return fd;
178 }
179 
close_output(android_logcat_context_internal * context)180 static void close_output(android_logcat_context_internal* context) {
181     // split output_from_error
182     if (context->error == context->output) {
183         context->output = nullptr;
184         context->output_fd = -1;
185     }
186     if (context->error && (context->output_fd == fileno(context->error))) {
187         context->output_fd = -1;
188     }
189     if (context->output_fd == context->error_fd) {
190         context->output_fd = -1;
191     }
192     // close output channel
193     if (context->output) {
194         if (context->output != stdout) {
195             if (context->output_fd == fileno(context->output)) {
196                 context->output_fd = -1;
197             }
198             if (context->fds[1] == fileno(context->output)) {
199                 context->fds[1] = -1;
200             }
201             fclose(context->output);
202         }
203         context->output = nullptr;
204     }
205     if (context->output_fd >= 0) {
206         if (context->output_fd != fileno(stdout)) {
207             if (context->fds[1] == context->output_fd) {
208                 context->fds[1] = -1;
209             }
210             posix_fadvise(context->output_fd, 0, 0, POSIX_FADV_DONTNEED);
211             close(context->output_fd);
212         }
213         context->output_fd = -1;
214     }
215 }
216 
close_error(android_logcat_context_internal * context)217 static void close_error(android_logcat_context_internal* context) {
218     // split error_from_output
219     if (context->output == context->error) {
220         context->error = nullptr;
221         context->error_fd = -1;
222     }
223     if (context->output && (context->error_fd == fileno(context->output))) {
224         context->error_fd = -1;
225     }
226     if (context->error_fd == context->output_fd) {
227         context->error_fd = -1;
228     }
229     // close error channel
230     if (context->error) {
231         if ((context->error != stderr) && (context->error != stdout)) {
232             if (context->error_fd == fileno(context->error)) {
233                 context->error_fd = -1;
234             }
235             if (context->fds[1] == fileno(context->error)) {
236                 context->fds[1] = -1;
237             }
238             fclose(context->error);
239         }
240         context->error = nullptr;
241     }
242     if (context->error_fd >= 0) {
243         if ((context->error_fd != fileno(stdout)) &&
244             (context->error_fd != fileno(stderr))) {
245             if (context->fds[1] == context->error_fd) context->fds[1] = -1;
246             close(context->error_fd);
247         }
248         context->error_fd = -1;
249     }
250 }
251 
rotateLogs(android_logcat_context_internal * context)252 static void rotateLogs(android_logcat_context_internal* context) {
253     int err;
254 
255     // Can't rotate logs if we're not outputting to a file
256     if (!context->outputFileName) return;
257 
258     close_output(context);
259 
260     // Compute the maximum number of digits needed to count up to
261     // maxRotatedLogs in decimal.  eg:
262     // maxRotatedLogs == 30
263     //   -> log10(30) == 1.477
264     //   -> maxRotationCountDigits == 2
265     int maxRotationCountDigits =
266         (context->maxRotatedLogs > 0)
267             ? (int)(floor(log10(context->maxRotatedLogs) + 1))
268             : 0;
269 
270     for (int i = context->maxRotatedLogs; i > 0; i--) {
271         std::string file1 = android::base::StringPrintf(
272             "%s.%.*d", context->outputFileName, maxRotationCountDigits, i);
273 
274         std::string file0;
275         if (!(i - 1)) {
276             file0 = android::base::StringPrintf("%s", context->outputFileName);
277         } else {
278             file0 =
279                 android::base::StringPrintf("%s.%.*d", context->outputFileName,
280                                             maxRotationCountDigits, i - 1);
281         }
282 
283         if (!file0.length() || !file1.length()) {
284             perror("while rotating log files");
285             break;
286         }
287 
288         err = rename(file0.c_str(), file1.c_str());
289 
290         if (err < 0 && errno != ENOENT) {
291             perror("while rotating log files");
292         }
293     }
294 
295     context->output_fd = openLogFile(context->outputFileName, context->logRotateSizeKBytes);
296 
297     if (context->output_fd < 0) {
298         logcat_panic(context, HELP_FALSE, "couldn't open output file");
299         return;
300     }
301     context->output = fdopen(context->output_fd, "web");
302     if (!context->output) {
303         logcat_panic(context, HELP_FALSE, "couldn't fdopen output file");
304         return;
305     }
306     if (context->stderr_stdout) {
307         close_error(context);
308         context->error = context->output;
309         context->error_fd = context->output_fd;
310     }
311 
312     context->outByteCount = 0;
313 }
314 
printBinary(android_logcat_context_internal * context,struct log_msg * buf)315 void printBinary(android_logcat_context_internal* context, struct log_msg* buf) {
316     size_t size = buf->len();
317 
318     TEMP_FAILURE_RETRY(write(context->output_fd, buf, size));
319 }
320 
regexOk(android_logcat_context_internal * context,const AndroidLogEntry & entry)321 static bool regexOk(android_logcat_context_internal* context,
322                     const AndroidLogEntry& entry) {
323     if (!context->regex) return true;
324 
325     return std::regex_search(entry.message, entry.message + entry.messageLen, *context->regex);
326 }
327 
processBuffer(android_logcat_context_internal * context,log_device_t * dev,struct log_msg * buf)328 static void processBuffer(android_logcat_context_internal* context,
329                           log_device_t* dev, struct log_msg* buf) {
330     int bytesWritten = 0;
331     int err;
332     AndroidLogEntry entry;
333     char binaryMsgBuf[1024];
334 
335     if (dev->binary) {
336         if (!context->eventTagMap && !context->hasOpenedEventTagMap) {
337             context->eventTagMap = android_openEventTagMap(nullptr);
338             context->hasOpenedEventTagMap = true;
339         }
340         err = android_log_processBinaryLogBuffer(
341             &buf->entry_v1, &entry, context->eventTagMap, binaryMsgBuf,
342             sizeof(binaryMsgBuf));
343         // printf(">>> pri=%d len=%d msg='%s'\n",
344         //    entry.priority, entry.messageLen, entry.message);
345     } else {
346         err = android_log_processLogBuffer(&buf->entry_v1, &entry);
347     }
348     if ((err < 0) && !context->debug) return;
349 
350     if (android_log_shouldPrintLine(
351             context->logformat, std::string(entry.tag, entry.tagLen).c_str(),
352             entry.priority)) {
353         bool match = regexOk(context, entry);
354 
355         context->printCount += match;
356         if (match || context->printItAnyways) {
357             bytesWritten = android_log_printLogLine(context->logformat,
358                                                     context->output_fd, &entry);
359 
360             if (bytesWritten < 0) {
361                 logcat_panic(context, HELP_FALSE, "output error");
362                 return;
363             }
364         }
365     }
366 
367     context->outByteCount += bytesWritten;
368 
369     if (context->logRotateSizeKBytes > 0 &&
370         (context->outByteCount / 1024) >= context->logRotateSizeKBytes) {
371         rotateLogs(context);
372     }
373 }
374 
maybePrintStart(android_logcat_context_internal * context,log_device_t * dev,bool printDividers)375 static void maybePrintStart(android_logcat_context_internal* context,
376                             log_device_t* dev, bool printDividers) {
377     if (!dev->printed || printDividers) {
378         if (context->devCount > 1 && !context->printBinary) {
379             char buf[1024];
380             snprintf(buf, sizeof(buf), "--------- %s %s\n",
381                      dev->printed ? "switch to" : "beginning of", dev->device);
382             if (write(context->output_fd, buf, strlen(buf)) < 0) {
383                 logcat_panic(context, HELP_FALSE, "output error");
384                 return;
385             }
386         }
387         dev->printed = true;
388     }
389 }
390 
setupOutputAndSchedulingPolicy(android_logcat_context_internal * context,bool blocking)391 static void setupOutputAndSchedulingPolicy(
392     android_logcat_context_internal* context, bool blocking) {
393     if (!context->outputFileName) return;
394 
395     if (blocking) {
396         // Lower priority and set to batch scheduling if we are saving
397         // the logs into files and taking continuous content.
398         if ((set_sched_policy(0, SP_BACKGROUND) < 0) && context->error) {
399             fprintf(context->error,
400                     "failed to set background scheduling policy\n");
401         }
402 
403         struct sched_param param;
404         memset(&param, 0, sizeof(param));
405         if (sched_setscheduler((pid_t)0, SCHED_BATCH, &param) < 0) {
406             fprintf(stderr, "failed to set to batch scheduler\n");
407         }
408 
409         if ((setpriority(PRIO_PROCESS, 0, ANDROID_PRIORITY_BACKGROUND) < 0) &&
410             context->error) {
411             fprintf(context->error, "failed set to priority\n");
412         }
413     }
414 
415     close_output(context);
416 
417     context->output_fd = openLogFile(context->outputFileName, context->logRotateSizeKBytes);
418 
419     if (context->output_fd < 0) {
420         logcat_panic(context, HELP_FALSE, "couldn't open output file");
421         return;
422     }
423 
424     struct stat statbuf;
425     if (fstat(context->output_fd, &statbuf) == -1) {
426         close_output(context);
427         logcat_panic(context, HELP_FALSE, "couldn't get output file stat\n");
428         return;
429     }
430 
431     if ((size_t)statbuf.st_size > SIZE_MAX || statbuf.st_size < 0) {
432         close_output(context);
433         logcat_panic(context, HELP_FALSE, "invalid output file stat\n");
434         return;
435     }
436 
437     context->output = fdopen(context->output_fd, "web");
438 
439     context->outByteCount = statbuf.st_size;
440 }
441 
442 // clang-format off
show_help(android_logcat_context_internal * context)443 static void show_help(android_logcat_context_internal* context) {
444     if (!context->error) return;
445 
446     const char* cmd = strrchr(context->argv[0], '/');
447     cmd = cmd ? cmd + 1 : context->argv[0];
448 
449     fprintf(context->error, "Usage: %s [options] [filterspecs]\n", cmd);
450 
451     fprintf(context->error, "options include:\n"
452                     "  -s              Set default filter to silent. Equivalent to filterspec '*:S'\n"
453                     "  -f <file>, --file=<file>               Log to file. Default is stdout\n"
454                     "  -r <kbytes>, --rotate-kbytes=<kbytes>\n"
455                     "                  Rotate log every kbytes. Requires -f option\n"
456                     "  -n <count>, --rotate-count=<count>\n"
457                     "                  Sets max number of rotated logs to <count>, default 4\n"
458                     "  --id=<id>       If the signature id for logging to file changes, then clear\n"
459                     "                  the fileset and continue\n"
460                     "  -v <format>, --format=<format>\n"
461                     "                  Sets log print format verb and adverbs, where <format> is:\n"
462                     "                    brief help long process raw tag thread threadtime time\n"
463                     "                  and individually flagged modifying adverbs can be added:\n"
464                     "                    color descriptive epoch monotonic printable uid\n"
465                     "                    usec UTC year zone\n"
466                     "                  Multiple -v parameters or comma separated list of format and\n"
467                     "                  format modifiers are allowed.\n"
468                     // private and undocumented nsec, no signal, too much noise
469                     // useful for -T or -t <timestamp> accurate testing though.
470                     "  -D, --dividers  Print dividers between each log buffer\n"
471                     "  -c, --clear     Clear (flush) the entire log and exit\n"
472                     "                  if Log to File specified, clear fileset instead\n"
473                     "  -d              Dump the log and then exit (don't block)\n"
474                     "  -e <expr>, --regex=<expr>\n"
475                     "                  Only print lines where the log message matches <expr>\n"
476                     "                  where <expr> is a regular expression\n"
477                     // Leave --head undocumented as alias for -m
478                     "  -m <count>, --max-count=<count>\n"
479                     "                  Quit after printing <count> lines. This is meant to be\n"
480                     "                  paired with --regex, but will work on its own.\n"
481                     "  --print         Paired with --regex and --max-count to let content bypass\n"
482                     "                  regex filter but still stop at number of matches.\n"
483                     // Leave --tail undocumented as alias for -t
484                     "  -t <count>      Print only the most recent <count> lines (implies -d)\n"
485                     "  -t '<time>'     Print most recent lines since specified time (implies -d)\n"
486                     "  -T <count>      Print only the most recent <count> lines (does not imply -d)\n"
487                     "  -T '<time>'     Print most recent lines since specified time (not imply -d)\n"
488                     "                  count is pure numerical, time is 'MM-DD hh:mm:ss.mmm...'\n"
489                     "                  'YYYY-MM-DD hh:mm:ss.mmm...' or 'sssss.mmm...' format\n"
490                     "  -g, --buffer-size                      Get the size of the ring buffer.\n"
491                     "  -G <size>, --buffer-size=<size>\n"
492                     "                  Set size of log ring buffer, may suffix with K or M.\n"
493                     "  -L, --last      Dump logs from prior to last reboot\n"
494                     "  -b <buffer>, --buffer=<buffer>         Request alternate ring buffer, 'main',\n"
495                     "                  'system', 'radio', 'events', 'crash', 'default' or 'all'.\n"
496                     "                  Additionally, 'kernel' for userdebug and eng builds, and\n"
497                     "                  'security' for Device Owner installations.\n"
498                     "                  Multiple -b parameters or comma separated list of buffers are\n"
499                     "                  allowed. Buffers interleaved.\n"
500                     "                  Default -b main,system,crash,kernel.\n"
501                     "  -B, --binary    Output the log in binary.\n"
502                     "  -S, --statistics                       Output statistics.\n"
503                     "  -p, --prune     Print prune white and ~black list. Service is specified as\n"
504                     "                  UID, UID/PID or /PID. Weighed for quicker pruning if prefix\n"
505                     "                  with ~, otherwise weighed for longevity if unadorned. All\n"
506                     "                  other pruning activity is oldest first. Special case ~!\n"
507                     "                  represents an automatic quicker pruning for the noisiest\n"
508                     "                  UID as determined by the current statistics.\n"
509                     "  -P '<list> ...', --prune='<list> ...'\n"
510                     "                  Set prune white and ~black list, using same format as\n"
511                     "                  listed above. Must be quoted.\n"
512                     "  --pid=<pid>     Only prints logs from the given pid.\n"
513                     // Check ANDROID_LOG_WRAP_DEFAULT_TIMEOUT value for match to 2 hours
514                     "  --wrap          Sleep for 2 hours or when buffer about to wrap whichever\n"
515                     "                  comes first. Improves efficiency of polling by providing\n"
516                     "                  an about-to-wrap wakeup.\n");
517 
518     fprintf(context->error, "\nfilterspecs are a series of \n"
519                    "  <tag>[:priority]\n\n"
520                    "where <tag> is a log component tag (or * for all) and priority is:\n"
521                    "  V    Verbose (default for <tag>)\n"
522                    "  D    Debug (default for '*')\n"
523                    "  I    Info\n"
524                    "  W    Warn\n"
525                    "  E    Error\n"
526                    "  F    Fatal\n"
527                    "  S    Silent (suppress all output)\n"
528                    "\n'*' by itself means '*:D' and <tag> by itself means <tag>:V.\n"
529                    "If no '*' filterspec or -s on command line, all filter defaults to '*:V'.\n"
530                    "eg: '*:S <tag>' prints only <tag>, '<tag>:S' suppresses all <tag> log messages.\n"
531                    "\nIf not specified on the command line, filterspec is set from ANDROID_LOG_TAGS.\n"
532                    "\nIf not specified with -v on command line, format is set from ANDROID_PRINTF_LOG\n"
533                    "or defaults to \"threadtime\"\n\n");
534 }
535 
show_format_help(android_logcat_context_internal * context)536 static void show_format_help(android_logcat_context_internal* context) {
537     if (!context->error) return;
538     fprintf(context->error,
539         "-v <format>, --format=<format> options:\n"
540         "  Sets log print format verb and adverbs, where <format> is:\n"
541         "    brief long process raw tag thread threadtime time\n"
542         "  and individually flagged modifying adverbs can be added:\n"
543         "    color descriptive epoch monotonic printable uid usec UTC year zone\n"
544         "\nSingle format verbs:\n"
545         "  brief      — Display priority/tag and PID of the process issuing the message.\n"
546         "  long       — Display all metadata fields, separate messages with blank lines.\n"
547         "  process    — Display PID only.\n"
548         "  raw        — Display the raw log message, with no other metadata fields.\n"
549         "  tag        — Display the priority/tag only.\n"
550         "  thread     — Display priority, PID and TID of process issuing the message.\n"
551         "  threadtime — Display the date, invocation time, priority, tag, and the PID\n"
552         "               and TID of the thread issuing the message. (the default format).\n"
553         "  time       — Display the date, invocation time, priority/tag, and PID of the\n"
554         "             process issuing the message.\n"
555         "\nAdverb modifiers can be used in combination:\n"
556         "  color       — Display in highlighted color to match priority. i.e. \x1B[38;5;231mVERBOSE\n"
557         "                \x1B[38;5;75mDEBUG \x1B[38;5;40mINFO \x1B[38;5;166mWARNING \x1B[38;5;196mERROR FATAL\x1B[0m\n"
558         "  descriptive — events logs only, descriptions from event-log-tags database.\n"
559         "  epoch       — Display time as seconds since Jan 1 1970.\n"
560         "  monotonic   — Display time as cpu seconds since last boot.\n"
561         "  printable   — Ensure that any binary logging content is escaped.\n"
562         "  uid         — If permitted, display the UID or Android ID of logged process.\n"
563         "  usec        — Display time down the microsecond precision.\n"
564         "  UTC         — Display time as UTC.\n"
565         "  year        — Add the year to the displayed time.\n"
566         "  zone        — Add the local timezone to the displayed time.\n"
567         "  \"<zone>\"    — Print using this public named timezone (experimental).\n\n"
568     );
569 }
570 // clang-format on
571 
setLogFormat(android_logcat_context_internal * context,const char * formatString)572 static int setLogFormat(android_logcat_context_internal* context,
573                         const char* formatString) {
574     AndroidLogPrintFormat format;
575 
576     format = android_log_formatFromString(formatString);
577 
578     // invalid string?
579     if (format == FORMAT_OFF) return -1;
580 
581     return android_log_setPrintFormat(context->logformat, format);
582 }
583 
format_of_size(unsigned long value)584 static std::pair<unsigned long, const char*> format_of_size(unsigned long value) {
585     static const char multipliers[][3] = {{""}, {"Ki"}, {"Mi"}, {"Gi"}};
586     size_t i;
587     for (i = 0;
588          (i < sizeof(multipliers) / sizeof(multipliers[0])) && (value >= 1024);
589          value /= 1024, ++i)
590         ;
591     return std::make_pair(value, multipliers[i]);
592 }
593 
594 // String to unsigned int, returns -1 if it fails
getSizeTArg(const char * ptr,size_t * val,size_t min=0,size_t max=SIZE_MAX)595 static bool getSizeTArg(const char* ptr, size_t* val, size_t min = 0,
596                         size_t max = SIZE_MAX) {
597     if (!ptr) return false;
598 
599     char* endp;
600     errno = 0;
601     size_t ret = (size_t)strtoll(ptr, &endp, 0);
602 
603     if (endp[0] || errno) return false;
604 
605     if ((ret > max) || (ret < min)) return false;
606 
607     *val = ret;
608     return true;
609 }
610 
logcat_panic(android_logcat_context_internal * context,enum helpType showHelp,const char * fmt,...)611 static void logcat_panic(android_logcat_context_internal* context,
612                          enum helpType showHelp, const char* fmt, ...) {
613     context->retval = EXIT_FAILURE;
614     if (!context->error) {
615         context->stop = true;
616         return;
617     }
618 
619     va_list args;
620     va_start(args, fmt);
621     vfprintf(context->error, fmt, args);
622     va_end(args);
623 
624     switch (showHelp) {
625         case HELP_TRUE:
626             show_help(context);
627             break;
628         case HELP_FORMAT:
629             show_format_help(context);
630             break;
631         case HELP_FALSE:
632         default:
633             break;
634     }
635 
636     context->stop = true;
637 }
638 
parseTime(log_time & t,const char * cp)639 static char* parseTime(log_time& t, const char* cp) {
640     char* ep = t.strptime(cp, "%m-%d %H:%M:%S.%q");
641     if (ep) return ep;
642     ep = t.strptime(cp, "%Y-%m-%d %H:%M:%S.%q");
643     if (ep) return ep;
644     return t.strptime(cp, "%s.%q");
645 }
646 
647 // Find last logged line in <outputFileName>, or <outputFileName>.1
lastLogTime(const char * outputFileName)648 static log_time lastLogTime(const char* outputFileName) {
649     log_time retval(log_time::EPOCH);
650     if (!outputFileName) return retval;
651 
652     std::string directory;
653     const char* file = strrchr(outputFileName, '/');
654     if (!file) {
655         directory = ".";
656         file = outputFileName;
657     } else {
658         directory = std::string(outputFileName, file - outputFileName);
659         ++file;
660     }
661 
662     std::unique_ptr<DIR, int (*)(DIR*)> dir(opendir(directory.c_str()),
663                                             closedir);
664     if (!dir.get()) return retval;
665 
666     log_time now(android_log_clockid());
667 
668     size_t len = strlen(file);
669     log_time modulo(0, NS_PER_SEC);
670     struct dirent* dp;
671 
672     while (!!(dp = readdir(dir.get()))) {
673         if ((dp->d_type != DT_REG) || !!strncmp(dp->d_name, file, len) ||
674             (dp->d_name[len] && ((dp->d_name[len] != '.') ||
675                                  (strtoll(dp->d_name + 1, nullptr, 10) != 1)))) {
676             continue;
677         }
678 
679         std::string file_name = directory;
680         file_name += "/";
681         file_name += dp->d_name;
682         std::string file;
683         if (!android::base::ReadFileToString(file_name, &file)) continue;
684 
685         bool found = false;
686         for (const auto& line : android::base::Split(file, "\n")) {
687             log_time t(log_time::EPOCH);
688             char* ep = parseTime(t, line.c_str());
689             if (!ep || (*ep != ' ')) continue;
690             // determine the time precision of the logs (eg: msec or usec)
691             for (unsigned long mod = 1UL; mod < modulo.tv_nsec; mod *= 10) {
692                 if (t.tv_nsec % (mod * 10)) {
693                     modulo.tv_nsec = mod;
694                     break;
695                 }
696             }
697             // We filter any times later than current as we may not have the
698             // year stored with each log entry. Also, since it is possible for
699             // entries to be recorded out of order (very rare) we select the
700             // maximum we find just in case.
701             if ((t < now) && (t > retval)) {
702                 retval = t;
703                 found = true;
704             }
705         }
706         // We count on the basename file to be the definitive end, so stop here.
707         if (!dp->d_name[len] && found) break;
708     }
709     if (retval == log_time::EPOCH) return retval;
710     // tail_time prints matching or higher, round up by the modulo to prevent
711     // a replay of the last entry we have just checked.
712     retval += modulo;
713     return retval;
714 }
715 
getenv(android_logcat_context_internal * context,const char * name)716 const char* getenv(android_logcat_context_internal* context, const char* name) {
717     if (!context->envp || !name || !*name) return nullptr;
718 
719     for (size_t len = strlen(name), i = 0; context->envp[i]; ++i) {
720         if (strncmp(context->envp[i], name, len)) continue;
721         if (context->envp[i][len] == '=') return &context->envp[i][len + 1];
722     }
723     return nullptr;
724 }
725 
726 }  // namespace android
727 
reportErrorName(const char ** current,const char * name,bool blockSecurity)728 void reportErrorName(const char** current, const char* name,
729                      bool blockSecurity) {
730     if (*current) return;
731     if (!blockSecurity || (android_name_to_log_id(name) != LOG_ID_SECURITY)) {
732         *current = name;
733     }
734 }
735 
__logcat(android_logcat_context_internal * context)736 static int __logcat(android_logcat_context_internal* context) {
737     using namespace android;
738     int err;
739     bool hasSetLogFormat = false;
740     bool clearLog = false;
741     bool allSelected = false;
742     bool getLogSize = false;
743     bool getPruneList = false;
744     bool printStatistics = false;
745     bool printDividers = false;
746     unsigned long setLogSize = 0;
747     const char* setPruneList = nullptr;
748     const char* setId = nullptr;
749     int mode = ANDROID_LOG_RDONLY;
750     std::string forceFilters;
751     log_device_t* dev;
752     struct logger_list* logger_list;
753     size_t tail_lines = 0;
754     log_time tail_time(log_time::EPOCH);
755     size_t pid = 0;
756     bool got_t = false;
757 
758     // object instantiations before goto's can happen
759     log_device_t unexpected("unexpected", false);
760     const char* openDeviceFail = nullptr;
761     const char* clearFail = nullptr;
762     const char* setSizeFail = nullptr;
763     const char* getSizeFail = nullptr;
764     int argc = context->argc;
765     char* const* argv = context->argv;
766 
767     context->output = stdout;
768     context->error = stderr;
769 
770     for (int i = 0; i < argc; ++i) {
771         // Simulate shell stderr redirect parsing
772         if ((argv[i][0] != '2') || (argv[i][1] != '>')) continue;
773 
774         // Append to file not implemented, just open file
775         size_t skip = (argv[i][2] == '>') + 2;
776         if (!strcmp(&argv[i][skip], "/dev/null")) {
777             context->stderr_null = true;
778         } else if (!strcmp(&argv[i][skip], "&1")) {
779             context->stderr_stdout = true;
780         } else {
781             // stderr file redirections are not supported
782             fprintf(context->stderr_stdout ? stdout : stderr,
783                     "stderr redirection to file %s unsupported, skipping\n",
784                     &argv[i][skip]);
785         }
786         // Only the first one
787         break;
788     }
789 
790     const char* filename = nullptr;
791     for (int i = 0; i < argc; ++i) {
792         // Simulate shell stdout redirect parsing
793         if (argv[i][0] != '>') continue;
794 
795         // Append to file not implemented, just open file
796         filename = &argv[i][(argv[i][1] == '>') + 1];
797         // Only the first one
798         break;
799     }
800 
801     // Deal with setting up file descriptors and FILE pointers
802     if (context->error_fd >= 0) {  // Is an error file descriptor supplied?
803         if (context->error_fd == context->output_fd) {
804             context->stderr_stdout = true;
805         } else if (context->stderr_null) {  // redirection told us to close it
806             close(context->error_fd);
807             context->error_fd = -1;
808         } else {  // All Ok, convert error to a FILE pointer
809             context->error = fdopen(context->error_fd, "web");
810             if (!context->error) {
811                 context->retval = -errno;
812                 fprintf(context->stderr_stdout ? stdout : stderr,
813                         "Failed to fdopen(error_fd=%d) %s\n", context->error_fd,
814                         strerror(errno));
815                 goto exit;
816             }
817         }
818     }
819     if (context->output_fd >= 0) {  // Is an output file descriptor supplied?
820         if (filename) {  // redirect to file, close supplied file descriptor.
821             close(context->output_fd);
822             context->output_fd = -1;
823         } else {  // All Ok, convert output to a FILE pointer
824             context->output = fdopen(context->output_fd, "web");
825             if (!context->output) {
826                 context->retval = -errno;
827                 fprintf(context->stderr_stdout ? stdout : context->error,
828                         "Failed to fdopen(output_fd=%d) %s\n",
829                         context->output_fd, strerror(errno));
830                 goto exit;
831             }
832         }
833     }
834     if (filename) {  // We supplied an output file redirected in command line
835         context->output = fopen(filename, "web");
836     }
837     // Deal with 2>&1
838     if (context->stderr_stdout) context->error = context->output;
839     // Deal with 2>/dev/null
840     if (context->stderr_null) {
841         context->error_fd = -1;
842         context->error = nullptr;
843     }
844     // Only happens if output=stdout or output=filename
845     if ((context->output_fd < 0) && context->output) {
846         context->output_fd = fileno(context->output);
847     }
848     // Only happens if error=stdout || error=stderr
849     if ((context->error_fd < 0) && context->error) {
850         context->error_fd = fileno(context->error);
851     }
852 
853     context->logformat = android_log_format_new();
854 
855     if (argc == 2 && !strcmp(argv[1], "--help")) {
856         show_help(context);
857         context->retval = EXIT_SUCCESS;
858         goto exit;
859     }
860 
861     // meant to catch comma-delimited values, but cast a wider
862     // net for stability dealing with possible mistaken inputs.
863     static const char delimiters[] = ",:; \t\n\r\f";
864 
865     optind = 0;
866     while (true) {
867         int option_index = 0;
868         // list of long-argument only strings for later comparison
869         static const char pid_str[] = "pid";
870         static const char debug_str[] = "debug";
871         static const char id_str[] = "id";
872         static const char wrap_str[] = "wrap";
873         static const char print_str[] = "print";
874         // clang-format off
875         static const struct option long_options[] = {
876           { "binary",        no_argument,       nullptr, 'B' },
877           { "buffer",        required_argument, nullptr, 'b' },
878           { "buffer-size",   optional_argument, nullptr, 'g' },
879           { "clear",         no_argument,       nullptr, 'c' },
880           { debug_str,       no_argument,       nullptr, 0 },
881           { "dividers",      no_argument,       nullptr, 'D' },
882           { "file",          required_argument, nullptr, 'f' },
883           { "format",        required_argument, nullptr, 'v' },
884           // hidden and undocumented reserved alias for --regex
885           { "grep",          required_argument, nullptr, 'e' },
886           // hidden and undocumented reserved alias for --max-count
887           { "head",          required_argument, nullptr, 'm' },
888           { "help",          no_argument,       nullptr, 'h' },
889           { id_str,          required_argument, nullptr, 0 },
890           { "last",          no_argument,       nullptr, 'L' },
891           { "max-count",     required_argument, nullptr, 'm' },
892           { pid_str,         required_argument, nullptr, 0 },
893           { print_str,       no_argument,       nullptr, 0 },
894           { "prune",         optional_argument, nullptr, 'p' },
895           { "regex",         required_argument, nullptr, 'e' },
896           { "rotate-count",  required_argument, nullptr, 'n' },
897           { "rotate-kbytes", required_argument, nullptr, 'r' },
898           { "statistics",    no_argument,       nullptr, 'S' },
899           // hidden and undocumented reserved alias for -t
900           { "tail",          required_argument, nullptr, 't' },
901           // support, but ignore and do not document, the optional argument
902           { wrap_str,        optional_argument, nullptr, 0 },
903           { nullptr,         0,                 nullptr, 0 }
904         };
905         // clang-format on
906 
907         int c = getopt_long(argc, argv, ":cdDhLt:T:gG:sQf:r:n:v:b:BSpP:m:e:", long_options,
908                             &option_index);
909         if (c == -1) break;
910 
911         switch (c) {
912             case 0:
913                 // only long options
914                 if (long_options[option_index].name == pid_str) {
915                     if (pid != 0) {
916                         logcat_panic(context, HELP_TRUE, "Only supports one PID argument.\n");
917                         goto exit;
918                     }
919 
920                     // ToDo: determine runtime PID_MAX?
921                     if (!getSizeTArg(optarg, &pid, 1)) {
922                         logcat_panic(context, HELP_TRUE, "%s %s out of range\n",
923                                      long_options[option_index].name, optarg);
924                         goto exit;
925                     }
926                     break;
927                 }
928                 if (long_options[option_index].name == wrap_str) {
929                     mode |= ANDROID_LOG_WRAP | ANDROID_LOG_RDONLY |
930                             ANDROID_LOG_NONBLOCK;
931                     // ToDo: implement API that supports setting a wrap timeout
932                     size_t dummy = ANDROID_LOG_WRAP_DEFAULT_TIMEOUT;
933                     if (optarg && !getSizeTArg(optarg, &dummy, 1)) {
934                         logcat_panic(context, HELP_TRUE, "%s %s out of range\n",
935                                      long_options[option_index].name, optarg);
936                         goto exit;
937                     }
938                     if ((dummy != ANDROID_LOG_WRAP_DEFAULT_TIMEOUT) &&
939                         context->error) {
940                         fprintf(context->error,
941                                 "WARNING: %s %u seconds, ignoring %zu\n",
942                                 long_options[option_index].name,
943                                 ANDROID_LOG_WRAP_DEFAULT_TIMEOUT, dummy);
944                     }
945                     break;
946                 }
947                 if (long_options[option_index].name == print_str) {
948                     context->printItAnyways = true;
949                     break;
950                 }
951                 if (long_options[option_index].name == debug_str) {
952                     context->debug = true;
953                     break;
954                 }
955                 if (long_options[option_index].name == id_str) {
956                     setId = (optarg && optarg[0]) ? optarg : nullptr;
957                 }
958                 break;
959 
960             case 's':
961                 // default to all silent
962                 android_log_addFilterRule(context->logformat, "*:s");
963                 break;
964 
965             case 'c':
966                 clearLog = true;
967                 mode |= ANDROID_LOG_WRONLY;
968                 break;
969 
970             case 'L':
971                 mode |= ANDROID_LOG_RDONLY | ANDROID_LOG_PSTORE |
972                         ANDROID_LOG_NONBLOCK;
973                 break;
974 
975             case 'd':
976                 mode |= ANDROID_LOG_RDONLY | ANDROID_LOG_NONBLOCK;
977                 break;
978 
979             case 't':
980                 got_t = true;
981                 mode |= ANDROID_LOG_RDONLY | ANDROID_LOG_NONBLOCK;
982                 FALLTHROUGH_INTENDED;
983             case 'T':
984                 if (strspn(optarg, "0123456789") != strlen(optarg)) {
985                     char* cp = parseTime(tail_time, optarg);
986                     if (!cp) {
987                         logcat_panic(context, HELP_FALSE, "-%c \"%s\" not in time format\n", c,
988                                      optarg);
989                         goto exit;
990                     }
991                     if (*cp) {
992                         char ch = *cp;
993                         *cp = '\0';
994                         if (context->error) {
995                             fprintf(context->error, "WARNING: -%c \"%s\"\"%c%s\" time truncated\n",
996                                     c, optarg, ch, cp + 1);
997                         }
998                         *cp = ch;
999                     }
1000                 } else {
1001                     if (!getSizeTArg(optarg, &tail_lines, 1)) {
1002                         if (context->error) {
1003                             fprintf(context->error, "WARNING: -%c %s invalid, setting to 1\n", c,
1004                                     optarg);
1005                         }
1006                         tail_lines = 1;
1007                     }
1008                 }
1009                 break;
1010 
1011             case 'D':
1012                 printDividers = true;
1013                 break;
1014 
1015             case 'e':
1016                 context->regex.reset(new std::regex(optarg));
1017                 break;
1018 
1019             case 'm': {
1020                 if (!getSizeTArg(optarg, &context->maxCount)) {
1021                     logcat_panic(context, HELP_FALSE,
1022                                  "-%c \"%s\" isn't an integer greater than zero\n", c, optarg);
1023                     goto exit;
1024                 }
1025             } break;
1026 
1027             case 'g':
1028                 if (!optarg) {
1029                     getLogSize = true;
1030                     break;
1031                 }
1032                 FALLTHROUGH_INTENDED;
1033 
1034             case 'G': {
1035                 char* cp;
1036                 if (strtoll(optarg, &cp, 0) > 0) {
1037                     setLogSize = strtoll(optarg, &cp, 0);
1038                 } else {
1039                     setLogSize = 0;
1040                 }
1041 
1042                 switch (*cp) {
1043                     case 'g':
1044                     case 'G':
1045                         setLogSize *= 1024;
1046                         FALLTHROUGH_INTENDED;
1047                     case 'm':
1048                     case 'M':
1049                         setLogSize *= 1024;
1050                         FALLTHROUGH_INTENDED;
1051                     case 'k':
1052                     case 'K':
1053                         setLogSize *= 1024;
1054                         FALLTHROUGH_INTENDED;
1055                     case '\0':
1056                         break;
1057 
1058                     default:
1059                         setLogSize = 0;
1060                 }
1061 
1062                 if (!setLogSize) {
1063                     logcat_panic(context, HELP_FALSE,
1064                                  "ERROR: -G <num><multiplier>\n");
1065                     goto exit;
1066                 }
1067             } break;
1068 
1069             case 'p':
1070                 if (!optarg) {
1071                     getPruneList = true;
1072                     break;
1073                 }
1074                 FALLTHROUGH_INTENDED;
1075 
1076             case 'P':
1077                 setPruneList = optarg;
1078                 break;
1079 
1080             case 'b': {
1081                 std::unique_ptr<char, void (*)(void*)> buffers(strdup(optarg), free);
1082                 char* arg = buffers.get();
1083                 unsigned idMask = 0;
1084                 char* sv = nullptr;  // protect against -ENOMEM above
1085                 while (!!(arg = strtok_r(arg, delimiters, &sv))) {
1086                     if (!strcmp(arg, "default")) {
1087                         idMask |= (1 << LOG_ID_MAIN) | (1 << LOG_ID_SYSTEM) |
1088                                   (1 << LOG_ID_CRASH);
1089                     } else if (!strcmp(arg, "all")) {
1090                         allSelected = true;
1091                         idMask = (unsigned)-1;
1092                     } else {
1093                         log_id_t log_id = android_name_to_log_id(arg);
1094                         const char* name = android_log_id_to_name(log_id);
1095 
1096                         if (!!strcmp(name, arg)) {
1097                             logcat_panic(context, HELP_TRUE,
1098                                          "unknown buffer %s\n", arg);
1099                             goto exit;
1100                         }
1101                         if (log_id == LOG_ID_SECURITY) allSelected = false;
1102                         idMask |= (1 << log_id);
1103                     }
1104                     arg = nullptr;
1105                 }
1106 
1107                 for (int i = LOG_ID_MIN; i < LOG_ID_MAX; ++i) {
1108                     const char* name = android_log_id_to_name((log_id_t)i);
1109                     log_id_t log_id = android_name_to_log_id(name);
1110 
1111                     if (log_id != (log_id_t)i) continue;
1112                     if (!(idMask & (1 << i))) continue;
1113 
1114                     bool found = false;
1115                     for (dev = context->devices; dev; dev = dev->next) {
1116                         if (!strcmp(name, dev->device)) {
1117                             found = true;
1118                             break;
1119                         }
1120                         if (!dev->next) break;
1121                     }
1122                     if (found) continue;
1123 
1124                     bool binary = !strcmp(name, "events") ||
1125                                   !strcmp(name, "security") ||
1126                                   !strcmp(name, "stats");
1127                     log_device_t* d = new log_device_t(name, binary);
1128 
1129                     if (dev) {
1130                         dev->next = d;
1131                         dev = d;
1132                     } else {
1133                         context->devices = dev = d;
1134                     }
1135                     context->devCount++;
1136                 }
1137             } break;
1138 
1139             case 'B':
1140                 context->printBinary = 1;
1141                 break;
1142 
1143             case 'f':
1144                 if ((tail_time == log_time::EPOCH) && !tail_lines) {
1145                     tail_time = lastLogTime(optarg);
1146                 }
1147                 // redirect output to a file
1148                 context->outputFileName = optarg;
1149                 break;
1150 
1151             case 'r':
1152                 if (!getSizeTArg(optarg, &context->logRotateSizeKBytes, 1)) {
1153                     logcat_panic(context, HELP_TRUE, "Invalid parameter \"%s\" to -r\n", optarg);
1154                     goto exit;
1155                 }
1156                 break;
1157 
1158             case 'n':
1159                 if (!getSizeTArg(optarg, &context->maxRotatedLogs, 1)) {
1160                     logcat_panic(context, HELP_TRUE, "Invalid parameter \"%s\" to -n\n", optarg);
1161                     goto exit;
1162                 }
1163                 break;
1164 
1165             case 'v': {
1166                 if (!strcmp(optarg, "help") || !strcmp(optarg, "--help")) {
1167                     show_format_help(context);
1168                     context->retval = EXIT_SUCCESS;
1169                     goto exit;
1170                 }
1171                 std::unique_ptr<char, void (*)(void*)> formats(strdup(optarg), free);
1172                 char* arg = formats.get();
1173                 char* sv = nullptr;  // protect against -ENOMEM above
1174                 while (!!(arg = strtok_r(arg, delimiters, &sv))) {
1175                     err = setLogFormat(context, arg);
1176                     if (err < 0) {
1177                         logcat_panic(context, HELP_FORMAT,
1178                                      "Invalid parameter \"%s\" to -v\n", arg);
1179                         goto exit;
1180                     }
1181                     arg = nullptr;
1182                     if (err) hasSetLogFormat = true;
1183                 }
1184             } break;
1185 
1186             case 'Q':
1187 #define LOGCAT_FILTER "androidboot.logcat="
1188 #define CONSOLE_PIPE_OPTION "androidboot.consolepipe="
1189 #define CONSOLE_OPTION "androidboot.console="
1190 #define QEMU_PROPERTY "ro.kernel.qemu"
1191 #define QEMU_CMDLINE "qemu.cmdline"
1192                 // This is a *hidden* option used to start a version of logcat
1193                 // in an emulated device only.  It basically looks for
1194                 // androidboot.logcat= on the kernel command line.  If
1195                 // something is found, it extracts a log filter and uses it to
1196                 // run the program. The logcat output will go to consolepipe if
1197                 // androiboot.consolepipe (e.g. qemu_pipe) is given, otherwise,
1198                 // it goes to androidboot.console (e.g. tty)
1199                 {
1200                     // if not in emulator, exit quietly
1201                     if (false == android::base::GetBoolProperty(QEMU_PROPERTY, false)) {
1202                         context->retval = EXIT_SUCCESS;
1203                         goto exit;
1204                     }
1205 
1206                     std::string cmdline = android::base::GetProperty(QEMU_CMDLINE, "");
1207                     if (cmdline.empty()) {
1208                         android::base::ReadFileToString("/proc/cmdline", &cmdline);
1209                     }
1210 
1211                     const char* logcatFilter = strstr(cmdline.c_str(), LOGCAT_FILTER);
1212                     // if nothing found or invalid filters, exit quietly
1213                     if (!logcatFilter) {
1214                         context->retval = EXIT_SUCCESS;
1215                         goto exit;
1216                     }
1217 
1218                     const char* p = logcatFilter + strlen(LOGCAT_FILTER);
1219                     const char* q = strpbrk(p, " \t\n\r");
1220                     if (!q) q = p + strlen(p);
1221                     forceFilters = std::string(p, q);
1222 
1223                     // redirect our output to the emulator console pipe or console
1224                     const char* consolePipe =
1225                         strstr(cmdline.c_str(), CONSOLE_PIPE_OPTION);
1226                     const char* console =
1227                         strstr(cmdline.c_str(), CONSOLE_OPTION);
1228 
1229                     if (consolePipe) {
1230                         p = consolePipe + strlen(CONSOLE_PIPE_OPTION);
1231                     } else if (console) {
1232                         p = console + strlen(CONSOLE_OPTION);
1233                     } else {
1234                         context->retval = EXIT_FAILURE;
1235                         goto exit;
1236                     }
1237 
1238                     q = strpbrk(p, " \t\n\r");
1239                     int len = q ? q - p : strlen(p);
1240                     std::string devname = "/dev/" + std::string(p, len);
1241                     std::string pipePurpose("pipe:logcat");
1242                     if (consolePipe) {
1243                         // example: "qemu_pipe,pipe:logcat"
1244                         // upon opening of /dev/qemu_pipe, the "pipe:logcat"
1245                         // string with trailing '\0' should be written to the fd
1246                         size_t pos = devname.find(',');
1247                         if (pos != std::string::npos) {
1248                             pipePurpose = devname.substr(pos + 1);
1249                             devname = devname.substr(0, pos);
1250                         }
1251                     }
1252                     cmdline.erase();
1253 
1254                     if (context->error) {
1255                         fprintf(context->error, "logcat using %s\n",
1256                                 devname.c_str());
1257                     }
1258 
1259                     FILE* fp = fopen(devname.c_str(), "web");
1260                     devname.erase();
1261                     if (!fp) break;
1262 
1263                     if (consolePipe) {
1264                         // need the trailing '\0'
1265                         if(!android::base::WriteFully(fileno(fp), pipePurpose.c_str(),
1266                                     pipePurpose.size() + 1)) {
1267                             fclose(fp);
1268                             context->retval = EXIT_FAILURE;
1269                             goto exit;
1270                         }
1271                     }
1272 
1273                     // close output and error channels, replace with console
1274                     android::close_output(context);
1275                     android::close_error(context);
1276                     context->stderr_stdout = true;
1277                     context->output = fp;
1278                     context->output_fd = fileno(fp);
1279                     if (context->stderr_null) break;
1280                     context->stderr_stdout = true;
1281                     context->error = fp;
1282                     context->error_fd = fileno(fp);
1283                 }
1284                 break;
1285 
1286             case 'S':
1287                 printStatistics = true;
1288                 break;
1289 
1290             case ':':
1291                 logcat_panic(context, HELP_TRUE, "Option -%c needs an argument\n", optopt);
1292                 goto exit;
1293 
1294             case 'h':
1295                 show_help(context);
1296                 show_format_help(context);
1297                 goto exit;
1298 
1299             default:
1300                 logcat_panic(context, HELP_TRUE, "Unrecognized Option %c\n", optopt);
1301                 goto exit;
1302         }
1303     }
1304 
1305     if (context->maxCount && got_t) {
1306         logcat_panic(context, HELP_TRUE,
1307                      "Cannot use -m (--max-count) and -t together\n");
1308         goto exit;
1309     }
1310     if (context->printItAnyways && (!context->regex || !context->maxCount)) {
1311         // One day it would be nice if --print -v color and --regex <expr>
1312         // could play with each other and show regex highlighted content.
1313         // clang-format off
1314         if (context->error) {
1315             fprintf(context->error, "WARNING: "
1316                             "--print ignored, to be used in combination with\n"
1317                                 "         "
1318                             "--regex <expr> and --max-count <N>\n");
1319         }
1320         context->printItAnyways = false;
1321     }
1322 
1323     if (!context->devices) {
1324         dev = context->devices = new log_device_t("main", false);
1325         context->devCount = 1;
1326         if (android_name_to_log_id("system") == LOG_ID_SYSTEM) {
1327             dev = dev->next = new log_device_t("system", false);
1328             context->devCount++;
1329         }
1330         if (android_name_to_log_id("crash") == LOG_ID_CRASH) {
1331             dev = dev->next = new log_device_t("crash", false);
1332             context->devCount++;
1333         }
1334         if (android_name_to_log_id("kernel") == LOG_ID_KERNEL) {
1335             dev = dev->next = new log_device_t("kernel", false);
1336             context->devCount++;
1337         }
1338     }
1339 
1340     if (!!context->logRotateSizeKBytes && !context->outputFileName) {
1341         logcat_panic(context, HELP_TRUE, "-r requires -f as well\n");
1342         goto exit;
1343     }
1344 
1345     if (!!setId) {
1346         if (!context->outputFileName) {
1347             logcat_panic(context, HELP_TRUE,
1348                          "--id='%s' requires -f as well\n", setId);
1349             goto exit;
1350         }
1351 
1352         std::string file_name = android::base::StringPrintf(
1353                                         "%s.id", context->outputFileName);
1354         std::string file;
1355         bool file_ok = android::base::ReadFileToString(file_name, &file);
1356         android::base::WriteStringToFile(setId, file_name, S_IRUSR | S_IWUSR,
1357                                          getuid(), getgid());
1358         if (!file_ok || !file.compare(setId)) setId = nullptr;
1359     }
1360 
1361     if (!hasSetLogFormat) {
1362         const char* logFormat = android::getenv(context, "ANDROID_PRINTF_LOG");
1363 
1364         if (!!logFormat) {
1365             std::unique_ptr<char, void (*)(void*)> formats(strdup(logFormat),
1366                                                            free);
1367             char* sv = nullptr;  // protect against -ENOMEM above
1368             char* arg = formats.get();
1369             while (!!(arg = strtok_r(arg, delimiters, &sv))) {
1370                 err = setLogFormat(context, arg);
1371                 // environment should not cause crash of logcat
1372                 if ((err < 0) && context->error) {
1373                     fprintf(context->error,
1374                             "invalid format in ANDROID_PRINTF_LOG '%s'\n", arg);
1375                 }
1376                 arg = nullptr;
1377                 if (err > 0) hasSetLogFormat = true;
1378             }
1379         }
1380         if (!hasSetLogFormat) {
1381             setLogFormat(context, "threadtime");
1382         }
1383     }
1384 
1385     if (forceFilters.size()) {
1386         err = android_log_addFilterString(context->logformat,
1387                                           forceFilters.c_str());
1388         if (err < 0) {
1389             logcat_panic(context, HELP_FALSE,
1390                          "Invalid filter expression in logcat args\n");
1391             goto exit;
1392         }
1393     } else if (argc == optind) {
1394         // Add from environment variable
1395         const char* env_tags_orig = android::getenv(context, "ANDROID_LOG_TAGS");
1396 
1397         if (!!env_tags_orig) {
1398             err = android_log_addFilterString(context->logformat,
1399                                               env_tags_orig);
1400 
1401             if (err < 0) {
1402                 logcat_panic(context, HELP_TRUE,
1403                             "Invalid filter expression in ANDROID_LOG_TAGS\n");
1404                 goto exit;
1405             }
1406         }
1407     } else {
1408         // Add from commandline
1409         for (int i = optind ; i < argc ; i++) {
1410             // skip stderr redirections of _all_ kinds
1411             if ((argv[i][0] == '2') && (argv[i][1] == '>')) continue;
1412             // skip stdout redirections of _all_ kinds
1413             if (argv[i][0] == '>') continue;
1414 
1415             err = android_log_addFilterString(context->logformat, argv[i]);
1416             if (err < 0) {
1417                 logcat_panic(context, HELP_TRUE,
1418                              "Invalid filter expression '%s'\n", argv[i]);
1419                 goto exit;
1420             }
1421         }
1422     }
1423 
1424     dev = context->devices;
1425     if (tail_time != log_time::EPOCH) {
1426         logger_list = android_logger_list_alloc_time(mode, tail_time, pid);
1427     } else {
1428         logger_list = android_logger_list_alloc(mode, tail_lines, pid);
1429     }
1430     // We have three orthogonal actions below to clear, set log size and
1431     // get log size. All sharing the same iteration loop.
1432     while (dev) {
1433         dev->logger_list = logger_list;
1434         dev->logger = android_logger_open(logger_list,
1435                                           android_name_to_log_id(dev->device));
1436         if (!dev->logger) {
1437             reportErrorName(&openDeviceFail, dev->device, allSelected);
1438             dev = dev->next;
1439             continue;
1440         }
1441 
1442         if (clearLog || setId) {
1443             if (context->outputFileName) {
1444                 int maxRotationCountDigits =
1445                     (context->maxRotatedLogs > 0) ?
1446                         (int)(floor(log10(context->maxRotatedLogs) + 1)) :
1447                         0;
1448 
1449                 for (int i = context->maxRotatedLogs ; i >= 0 ; --i) {
1450                     std::string file;
1451 
1452                     if (!i) {
1453                         file = android::base::StringPrintf(
1454                             "%s", context->outputFileName);
1455                     } else {
1456                         file = android::base::StringPrintf("%s.%.*d",
1457                             context->outputFileName, maxRotationCountDigits, i);
1458                     }
1459 
1460                     if (!file.length()) {
1461                         perror("while clearing log files");
1462                         reportErrorName(&clearFail, dev->device, allSelected);
1463                         break;
1464                     }
1465 
1466                     err = unlink(file.c_str());
1467 
1468                     if (err < 0 && errno != ENOENT && !clearFail) {
1469                         perror("while clearing log files");
1470                         reportErrorName(&clearFail, dev->device, allSelected);
1471                     }
1472                 }
1473             } else if (android_logger_clear(dev->logger)) {
1474                 reportErrorName(&clearFail, dev->device, allSelected);
1475             }
1476         }
1477 
1478         if (setLogSize) {
1479             if (android_logger_set_log_size(dev->logger, setLogSize)) {
1480                 reportErrorName(&setSizeFail, dev->device, allSelected);
1481             }
1482         }
1483 
1484         if (getLogSize) {
1485             long size = android_logger_get_log_size(dev->logger);
1486             long readable = android_logger_get_log_readable_size(dev->logger);
1487 
1488             if ((size < 0) || (readable < 0)) {
1489                 reportErrorName(&getSizeFail, dev->device, allSelected);
1490             } else {
1491                 auto size_format = format_of_size(size);
1492                 auto readable_format = format_of_size(readable);
1493                 std::string str = android::base::StringPrintf(
1494                        "%s: ring buffer is %lu %sB (%lu %sB consumed),"
1495                          " max entry is %d B, max payload is %d B\n",
1496                        dev->device,
1497                        size_format.first, size_format.second,
1498                        readable_format.first, readable_format.second,
1499                        (int)LOGGER_ENTRY_MAX_LEN,
1500                        (int)LOGGER_ENTRY_MAX_PAYLOAD);
1501                 TEMP_FAILURE_RETRY(write(context->output_fd,
1502                                          str.data(), str.length()));
1503             }
1504         }
1505 
1506         dev = dev->next;
1507     }
1508 
1509     context->retval = EXIT_SUCCESS;
1510 
1511     // report any errors in the above loop and exit
1512     if (openDeviceFail) {
1513         logcat_panic(context, HELP_FALSE,
1514                      "Unable to open log device '%s'\n", openDeviceFail);
1515         goto close;
1516     }
1517     if (clearFail) {
1518         logcat_panic(context, HELP_FALSE,
1519                      "failed to clear the '%s' log\n", clearFail);
1520         goto close;
1521     }
1522     if (setSizeFail) {
1523         logcat_panic(context, HELP_FALSE,
1524                      "failed to set the '%s' log size\n", setSizeFail);
1525         goto close;
1526     }
1527     if (getSizeFail) {
1528         logcat_panic(context, HELP_FALSE,
1529                      "failed to get the readable '%s' log size", getSizeFail);
1530         goto close;
1531     }
1532 
1533     if (setPruneList) {
1534         size_t len = strlen(setPruneList);
1535         // extra 32 bytes are needed by android_logger_set_prune_list
1536         size_t bLen = len + 32;
1537         char* buf = nullptr;
1538         if (asprintf(&buf, "%-*s", (int)(bLen - 1), setPruneList) > 0) {
1539             buf[len] = '\0';
1540             if (android_logger_set_prune_list(logger_list, buf, bLen)) {
1541                 logcat_panic(context, HELP_FALSE,
1542                              "failed to set the prune list");
1543             }
1544             free(buf);
1545         } else {
1546             logcat_panic(context, HELP_FALSE,
1547                          "failed to set the prune list (alloc)");
1548         }
1549         goto close;
1550     }
1551 
1552     if (printStatistics || getPruneList) {
1553         size_t len = 8192;
1554         char* buf;
1555 
1556         for (int retry = 32; (retry >= 0) && ((buf = new char[len]));
1557              delete[] buf, buf = nullptr, --retry) {
1558             if (getPruneList) {
1559                 android_logger_get_prune_list(logger_list, buf, len);
1560             } else {
1561                 android_logger_get_statistics(logger_list, buf, len);
1562             }
1563             buf[len - 1] = '\0';
1564             if (atol(buf) < 3) {
1565                 delete[] buf;
1566                 buf = nullptr;
1567                 break;
1568             }
1569             size_t ret = atol(buf) + 1;
1570             if (ret <= len) {
1571                 len = ret;
1572                 break;
1573             }
1574             len = ret;
1575         }
1576 
1577         if (!buf) {
1578             logcat_panic(context, HELP_FALSE, "failed to read data");
1579             goto close;
1580         }
1581 
1582         // remove trailing FF
1583         char* cp = buf + len - 1;
1584         *cp = '\0';
1585         bool truncated = *--cp != '\f';
1586         if (!truncated) *cp = '\0';
1587 
1588         // squash out the byte count
1589         cp = buf;
1590         if (!truncated) {
1591             while (isdigit(*cp)) ++cp;
1592             if (*cp == '\n') ++cp;
1593         }
1594 
1595         len = strlen(cp);
1596         TEMP_FAILURE_RETRY(write(context->output_fd, cp, len));
1597         delete[] buf;
1598         goto close;
1599     }
1600 
1601     if (getLogSize || setLogSize || clearLog) goto close;
1602 
1603     setupOutputAndSchedulingPolicy(context, !(mode & ANDROID_LOG_NONBLOCK));
1604     if (context->stop) goto close;
1605 
1606     // LOG_EVENT_INT(10, 12345);
1607     // LOG_EVENT_LONG(11, 0x1122334455667788LL);
1608     // LOG_EVENT_STRING(0, "whassup, doc?");
1609 
1610     dev = nullptr;
1611 
1612     while (!context->stop &&
1613            (!context->maxCount || (context->printCount < context->maxCount))) {
1614         struct log_msg log_msg;
1615         int ret = android_logger_list_read(logger_list, &log_msg);
1616         if (!ret) {
1617             logcat_panic(context, HELP_FALSE, "read: unexpected EOF!\n");
1618             break;
1619         }
1620 
1621         if (ret < 0) {
1622             if (ret == -EAGAIN) break;
1623 
1624             if (ret == -EIO) {
1625                 logcat_panic(context, HELP_FALSE, "read: unexpected EOF!\n");
1626                 break;
1627             }
1628             if (ret == -EINVAL) {
1629                 logcat_panic(context, HELP_FALSE, "read: unexpected length.\n");
1630                 break;
1631             }
1632             logcat_panic(context, HELP_FALSE, "logcat read failure\n");
1633             break;
1634         }
1635 
1636         log_device_t* d;
1637         for (d = context->devices; d; d = d->next) {
1638             if (android_name_to_log_id(d->device) == log_msg.id()) break;
1639         }
1640         if (!d) {
1641             context->devCount = 2; // set to Multiple
1642             d = &unexpected;
1643             d->binary = log_msg.id() == LOG_ID_EVENTS;
1644         }
1645 
1646         if (dev != d) {
1647             dev = d;
1648             maybePrintStart(context, dev, printDividers);
1649             if (context->stop) break;
1650         }
1651         if (context->printBinary) {
1652             printBinary(context, &log_msg);
1653         } else {
1654             processBuffer(context, dev, &log_msg);
1655         }
1656     }
1657 
1658 close:
1659     // Short and sweet. Implemented generic version in android_logcat_destroy.
1660     while (!!(dev = context->devices)) {
1661         context->devices = dev->next;
1662         delete dev;
1663     }
1664     android_logger_list_free(logger_list);
1665 
1666 exit:
1667     // close write end of pipe to help things along
1668     if (context->output_fd == context->fds[1]) {
1669         android::close_output(context);
1670     }
1671     if (context->error_fd == context->fds[1]) {
1672         android::close_error(context);
1673     }
1674     if (context->fds[1] >= 0) {
1675         // NB: should be closed by the above
1676         int save_errno = errno;
1677         close(context->fds[1]);
1678         errno = save_errno;
1679         context->fds[1] = -1;
1680     }
1681     context->thread_stopped = true;
1682     return context->retval;
1683 }
1684 
1685 // Can block
android_logcat_run_command(android_logcat_context ctx,int output,int error,int argc,char * const * argv,char * const * envp)1686 int android_logcat_run_command(android_logcat_context ctx,
1687                                int output, int error,
1688                                int argc, char* const* argv,
1689                                char* const* envp) {
1690     android_logcat_context_internal* context = ctx;
1691 
1692     context->output_fd = output;
1693     context->error_fd = error;
1694     context->argc = argc;
1695     context->argv = argv;
1696     context->envp = envp;
1697     context->stop = false;
1698     context->thread_stopped = false;
1699     return __logcat(context);
1700 }
1701 
1702 // Finished with context
android_logcat_destroy(android_logcat_context * ctx)1703 int android_logcat_destroy(android_logcat_context* ctx) {
1704     android_logcat_context_internal* context = *ctx;
1705 
1706     if (!context) return -EBADF;
1707 
1708     *ctx = nullptr;
1709 
1710     context->stop = true;
1711 
1712     while (context->thread_stopped == false) {
1713         // Makes me sad, replace thread_stopped with semaphore.  Short lived.
1714         sched_yield();
1715     }
1716 
1717     context->argv_hold.clear();
1718     context->args.clear();
1719     context->envp_hold.clear();
1720     context->envs.clear();
1721     if (context->fds[0] >= 0) {
1722         close(context->fds[0]);
1723         context->fds[0] = -1;
1724     }
1725     android::close_output(context);
1726     android::close_error(context);
1727 
1728     if (context->fds[1] >= 0) {
1729         // NB: this should be closed by close_output, but just in case...
1730         close(context->fds[1]);
1731         context->fds[1] = -1;
1732     }
1733 
1734     android_closeEventTagMap(context->eventTagMap);
1735 
1736     // generic cleanup of devices list to handle all possible dirty cases
1737     log_device_t* dev;
1738     while (!!(dev = context->devices)) {
1739         struct logger_list* logger_list = dev->logger_list;
1740         if (logger_list) {
1741             for (log_device_t* d = dev; d; d = d->next) {
1742                 if (d->logger_list == logger_list) d->logger_list = nullptr;
1743             }
1744             android_logger_list_free(logger_list);
1745         }
1746         context->devices = dev->next;
1747         delete dev;
1748     }
1749 
1750     int retval = context->retval;
1751 
1752     free(context);
1753 
1754     return retval;
1755 }
1756