summaryrefslogtreecommitdiffstats
blob: 3bc9f5a676e19497dfc42e6a869702b664c02372 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
/*
**
** Copyright 2006-2014, 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.
*/

#define _GNU_SOURCE /* for asprintf */

#include <ctype.h>
#include <stdio.h>
#include <errno.h>
#include <stdlib.h>
#include <stdint.h>
#include <string.h>
#include <assert.h>
#include <arpa/inet.h>

#include <log/logd.h>
#include <log/logprint.h>

typedef struct FilterInfo_t {
    char *mTag;
    android_LogPriority mPri;
    struct FilterInfo_t *p_next;
} FilterInfo;

struct AndroidLogFormat_t {
    android_LogPriority global_pri;
    FilterInfo *filters;
    AndroidLogPrintFormat format;
};

static FilterInfo * filterinfo_new(const char * tag, android_LogPriority pri)
{
    FilterInfo *p_ret;

    p_ret = (FilterInfo *)calloc(1, sizeof(FilterInfo));
    p_ret->mTag = strdup(tag);
    p_ret->mPri = pri;

    return p_ret;
}

static void filterinfo_free(FilterInfo *p_info)
{
    if (p_info == NULL) {
        return;
    }

    free(p_info->mTag);
    p_info->mTag = NULL;
}

/*
 * Note: also accepts 0-9 priorities
 * returns ANDROID_LOG_UNKNOWN if the character is unrecognized
 */
static android_LogPriority filterCharToPri (char c)
{
    android_LogPriority pri;

    c = tolower(c);

    if (c >= '0' && c <= '9') {
        if (c >= ('0'+ANDROID_LOG_SILENT)) {
            pri = ANDROID_LOG_VERBOSE;
        } else {
            pri = (android_LogPriority)(c - '0');
        }
    } else if (c == 'v') {
        pri = ANDROID_LOG_VERBOSE;
    } else if (c == 'd') {
        pri = ANDROID_LOG_DEBUG;
    } else if (c == 'i') {
        pri = ANDROID_LOG_INFO;
    } else if (c == 'w') {
        pri = ANDROID_LOG_WARN;
    } else if (c == 'e') {
        pri = ANDROID_LOG_ERROR;
    } else if (c == 'f') {
        pri = ANDROID_LOG_FATAL;
    } else if (c == 's') {
        pri = ANDROID_LOG_SILENT;
    } else if (c == '*') {
        pri = ANDROID_LOG_DEFAULT;
    } else {
        pri = ANDROID_LOG_UNKNOWN;
    }

    return pri;
}

static char filterPriToChar (android_LogPriority pri)
{
    switch (pri) {
        case ANDROID_LOG_VERBOSE:       return 'V';
        case ANDROID_LOG_DEBUG:         return 'D';
        case ANDROID_LOG_INFO:          return 'I';
        case ANDROID_LOG_WARN:          return 'W';
        case ANDROID_LOG_ERROR:         return 'E';
        case ANDROID_LOG_FATAL:         return 'F';
        case ANDROID_LOG_SILENT:        return 'S';

        case ANDROID_LOG_DEFAULT:
        case ANDROID_LOG_UNKNOWN:
        default:                        return '?';
    }
}

static android_LogPriority filterPriForTag(
        AndroidLogFormat *p_format, const char *tag)
{
    FilterInfo *p_curFilter;

    for (p_curFilter = p_format->filters
            ; p_curFilter != NULL
            ; p_curFilter = p_curFilter->p_next
    ) {
        if (0 == strcmp(tag, p_curFilter->mTag)) {
            if (p_curFilter->mPri == ANDROID_LOG_DEFAULT) {
                return p_format->global_pri;
            } else {
                return p_curFilter->mPri;
            }
        }
    }

    return p_format->global_pri;
}

/** for debugging */
static void dumpFilters(AndroidLogFormat *p_format)
{
    FilterInfo *p_fi;

    for (p_fi = p_format->filters ; p_fi != NULL ; p_fi = p_fi->p_next) {
        char cPri = filterPriToChar(p_fi->mPri);
        if (p_fi->mPri == ANDROID_LOG_DEFAULT) {
            cPri = filterPriToChar(p_format->global_pri);
        }
        fprintf(stderr,"%s:%c\n", p_fi->mTag, cPri);
    }

    fprintf(stderr,"*:%c\n", filterPriToChar(p_format->global_pri));

}

/**
 * returns 1 if this log line should be printed based on its priority
 * and tag, and 0 if it should not
 */
int android_log_shouldPrintLine (
        AndroidLogFormat *p_format, const char *tag, android_LogPriority pri)
{
    return pri >= filterPriForTag(p_format, tag);
}

AndroidLogFormat *android_log_format_new()
{
    AndroidLogFormat *p_ret;

    p_ret = calloc(1, sizeof(AndroidLogFormat));

    p_ret->global_pri = ANDROID_LOG_VERBOSE;
    p_ret->format = FORMAT_BRIEF;

    return p_ret;
}

void android_log_format_free(AndroidLogFormat *p_format)
{
    FilterInfo *p_info, *p_info_old;

    p_info = p_format->filters;

    while (p_info != NULL) {
        p_info_old = p_info;
        p_info = p_info->p_next;

        free(p_info_old);
    }

    free(p_format);
}



void android_log_setPrintFormat(AndroidLogFormat *p_format,
        AndroidLogPrintFormat format)
{
    p_format->format=format;
}

/**
 * Returns FORMAT_OFF on invalid string
 */
AndroidLogPrintFormat android_log_formatFromString(const char * formatString)
{
    static AndroidLogPrintFormat format;

    if (strcmp(formatString, "brief") == 0) format = FORMAT_BRIEF;
    else if (strcmp(formatString, "process") == 0) format = FORMAT_PROCESS;
    else if (strcmp(formatString, "tag") == 0) format = FORMAT_TAG;
    else if (strcmp(formatString, "thread") == 0) format = FORMAT_THREAD;
    else if (strcmp(formatString, "raw") == 0) format = FORMAT_RAW;
    else if (strcmp(formatString, "time") == 0) format = FORMAT_TIME;
    else if (strcmp(formatString, "threadtime") == 0) format = FORMAT_THREADTIME;
    else if (strcmp(formatString, "long") == 0) format = FORMAT_LONG;
    else format = FORMAT_OFF;

    return format;
}

/**
 * filterExpression: a single filter expression
 * eg "AT:d"
 *
 * returns 0 on success and -1 on invalid expression
 *
 * Assumes single threaded execution
 */

int android_log_addFilterRule(AndroidLogFormat *p_format,
        const char *filterExpression)
{
    size_t i=0;
    size_t tagNameLength;
    android_LogPriority pri = ANDROID_LOG_DEFAULT;

    tagNameLength = strcspn(filterExpression, ":");

    if (tagNameLength == 0) {
        goto error;
    }

    if(filterExpression[tagNameLength] == ':') {
        pri = filterCharToPri(filterExpression[tagNameLength+1]);

        if (pri == ANDROID_LOG_UNKNOWN) {
            goto error;
        }
    }

    if(0 == strncmp("*", filterExpression, tagNameLength)) {
        // This filter expression refers to the global filter
        // The default level for this is DEBUG if the priority
        // is unspecified
        if (pri == ANDROID_LOG_DEFAULT) {
            pri = ANDROID_LOG_DEBUG;
        }

        p_format->global_pri = pri;
    } else {
        // for filter expressions that don't refer to the global
        // filter, the default is verbose if the priority is unspecified
        if (pri == ANDROID_LOG_DEFAULT) {
            pri = ANDROID_LOG_VERBOSE;
        }

        char *tagName;

// Presently HAVE_STRNDUP is never defined, so the second case is always taken
// Darwin doesn't have strnup, everything else does
#ifdef HAVE_STRNDUP
        tagName = strndup(filterExpression, tagNameLength);
#else
        //a few extra bytes copied...
        tagName = strdup(filterExpression);
        tagName[tagNameLength] = '\0';
#endif /*HAVE_STRNDUP*/

        FilterInfo *p_fi = filterinfo_new(tagName, pri);
        free(tagName);

        p_fi->p_next = p_format->filters;
        p_format->filters = p_fi;
    }

    return 0;
error:
    return -1;
}


/**
 * filterString: a comma/whitespace-separated set of filter expressions
 *
 * eg "AT:d *:i"
 *
 * returns 0 on success and -1 on invalid expression
 *
 * Assumes single threaded execution
 *
 */

int android_log_addFilterString(AndroidLogFormat *p_format,
        const char *filterString)
{
    char *filterStringCopy = strdup (filterString);
    char *p_cur = filterStringCopy;
    char *p_ret;
    int err;

    // Yes, I'm using strsep
    while (NULL != (p_ret = strsep(&p_cur, " \t,"))) {
        // ignore whitespace-only entries
        if(p_ret[0] != '\0') {
            err = android_log_addFilterRule(p_format, p_ret);

            if (err < 0) {
                goto error;
            }
        }
    }

    free (filterStringCopy);
    return 0;
error:
    free (filterStringCopy);
    return -1;
}

static inline char * strip_end(char *str)
{
    char *end = str + strlen(str) - 1;

    while (end >= str && isspace(*end))
        *end-- = '\0';
    return str;
}

/**
 * Splits a wire-format buffer into an AndroidLogEntry
 * entry allocated by caller. Pointers will point directly into buf
 *
 * Returns 0 on success and -1 on invalid wire format (entry will be
 * in unspecified state)
 */
int android_log_processLogBuffer(struct logger_entry *buf,
                                 AndroidLogEntry *entry)
{
    entry->tv_sec = buf->sec;
    entry->tv_nsec = buf->nsec;
    entry->pid = buf->pid;
    entry->tid = buf->tid;

    /*
     * format: <priority:1><tag:N>\0<message:N>\0
     *
     * tag str
     *   starts at buf->msg+1
     * msg
     *   starts at buf->msg+1+len(tag)+1
     *
     * The message may have been truncated by the kernel log driver.
     * When that happens, we must null-terminate the message ourselves.
     */
    if (buf->len < 3) {
        // An well-formed entry must consist of at least a priority
        // and two null characters
        fprintf(stderr, "+++ LOG: entry too small\n");
        return -1;
    }

    int msgStart = -1;
    int msgEnd = -1;

    int i;
    char *msg = buf->msg;
    struct logger_entry_v2 *buf2 = (struct logger_entry_v2 *)buf;
    if (buf2->hdr_size) {
        msg = ((char *)buf2) + buf2->hdr_size;
    }
    for (i = 1; i < buf->len; i++) {
        if (msg[i] == '\0') {
            if (msgStart == -1) {
                msgStart = i + 1;
            } else {
                msgEnd = i;
                break;
            }
        }
    }

    if (msgStart == -1) {
        fprintf(stderr, "+++ LOG: malformed log message\n");
        return -1;
    }
    if (msgEnd == -1) {
        // incoming message not null-terminated; force it
        msgEnd = buf->len - 1;
        msg[msgEnd] = '\0';
    }

    entry->priority = msg[0];
    entry->tag = msg + 1;
    entry->message = msg + msgStart;
    entry->messageLen = msgEnd - msgStart;

    return 0;
}

/*
 * Extract a 4-byte value from a byte stream.
 */
static inline uint32_t get4LE(const uint8_t* src)
{
    return src[0] | (src[1] << 8) | (src[2] << 16) | (src[3] << 24);
}

/*
 * Extract an 8-byte value from a byte stream.
 */
static inline uint64_t get8LE(const uint8_t* src)
{
    uint32_t low, high;

    low = src[0] | (src[1] << 8) | (src[2] << 16) | (src[3] << 24);
    high = src[4] | (src[5] << 8) | (src[6] << 16) | (src[7] << 24);
    return ((long long) high << 32) | (long long) low;
}


/*
 * Recursively convert binary log data to printable form.
 *
 * This needs to be recursive because you can have lists of lists.
 *
 * If we run out of room, we stop processing immediately.  It's important
 * for us to check for space on every output element to avoid producing
 * garbled output.
 *
 * Returns 0 on success, 1 on buffer full, -1 on failure.
 */
static int android_log_printBinaryEvent(const unsigned char** pEventData,
    size_t* pEventDataLen, char** pOutBuf, size_t* pOutBufLen)
{
    const unsigned char* eventData = *pEventData;
    size_t eventDataLen = *pEventDataLen;
    char* outBuf = *pOutBuf;
    size_t outBufLen = *pOutBufLen;
    unsigned char type;
    size_t outCount;
    int result = 0;

    if (eventDataLen < 1)
        return -1;
    type = *eventData++;
    eventDataLen--;

    //fprintf(stderr, "--- type=%d (rem len=%d)\n", type, eventDataLen);

    switch (type) {
    case EVENT_TYPE_INT:
        /* 32-bit signed int */
        {
            int ival;

            if (eventDataLen < 4)
                return -1;
            ival = get4LE(eventData);
            eventData += 4;
            eventDataLen -= 4;

            outCount = snprintf(outBuf, outBufLen, "%d", ival);
            if (outCount < outBufLen) {
                outBuf += outCount;
                outBufLen -= outCount;
            } else {
                /* halt output */
                goto no_room;
            }
        }
        break;
    case EVENT_TYPE_LONG:
        /* 64-bit signed long */
        {
            long long lval;

            if (eventDataLen < 8)
                return -1;
            lval = get8LE(eventData);
            eventData += 8;
            eventDataLen -= 8;

            outCount = snprintf(outBuf, outBufLen, "%lld", lval);
            if (outCount < outBufLen) {
                outBuf += outCount;
                outBufLen -= outCount;
            } else {
                /* halt output */
                goto no_room;
            }
        }
        break;
    case EVENT_TYPE_STRING:
        /* UTF-8 chars, not NULL-terminated */
        {
            unsigned int strLen;

            if (eventDataLen < 4)
                return -1;
            strLen = get4LE(eventData);
            eventData += 4;
            eventDataLen -= 4;

            if (eventDataLen < strLen)
                return -1;

            if (strLen < outBufLen) {
                memcpy(outBuf, eventData, strLen);
                outBuf += strLen;
                outBufLen -= strLen;
            } else if (outBufLen > 0) {
                /* copy what we can */
                memcpy(outBuf, eventData, outBufLen);
                outBuf += outBufLen;
                outBufLen -= outBufLen;
                goto no_room;
            }
            eventData += strLen;
            eventDataLen -= strLen;
            break;
        }
    case EVENT_TYPE_LIST:
        /* N items, all different types */
        {
            unsigned char count;
            int i;

            if (eventDataLen < 1)
                return -1;

            count = *eventData++;
            eventDataLen--;

            if (outBufLen > 0) {
                *outBuf++ = '[';
                outBufLen--;
            } else {
                goto no_room;
            }

            for (i = 0; i < count; i++) {
                result = android_log_printBinaryEvent(&eventData, &eventDataLen,
                        &outBuf, &outBufLen);
                if (result != 0)
                    goto bail;

                if (i < count-1) {
                    if (outBufLen > 0) {
                        *outBuf++ = ',';
                        outBufLen--;
                    } else {
                        goto no_room;
                    }
                }
            }

            if (outBufLen > 0) {
                *outBuf++ = ']';
                outBufLen--;
            } else {
                goto no_room;
            }
        }
        break;
    default:
        fprintf(stderr, "Unknown binary event type %d\n", type);
        return -1;
    }

bail:
    *pEventData = eventData;
    *pEventDataLen = eventDataLen;
    *pOutBuf = outBuf;
    *pOutBufLen = outBufLen;
    return result;

no_room:
    result = 1;
    goto bail;
}

/**
 * Convert a binary log entry to ASCII form.
 *
 * For convenience we mimic the processLogBuffer API.  There is no
 * pre-defined output length for the binary data, since we're free to format
 * it however we choose, which means we can't really use a fixed-size buffer
 * here.
 */
int android_log_processBinaryLogBuffer(struct logger_entry *buf,
    AndroidLogEntry *entry, const EventTagMap* map, char* messageBuf,
    int messageBufLen)
{
    size_t inCount;
    unsigned int tagIndex;
    const unsigned char* eventData;

    entry->tv_sec = buf->sec;
    entry->tv_nsec = buf->nsec;
    entry->priority = ANDROID_LOG_INFO;
    entry->pid = buf->pid;
    entry->tid = buf->tid;

    /*
     * Pull the tag out.
     */
    eventData = (const unsigned char*) buf->msg;
    struct logger_entry_v2 *buf2 = (struct logger_entry_v2 *)buf;
    if (buf2->hdr_size) {
        eventData = ((unsigned char *)buf2) + buf2->hdr_size;
    }
    inCount = buf->len;
    if (inCount < 4)
        return -1;
    tagIndex = get4LE(eventData);
    eventData += 4;
    inCount -= 4;

    if (map != NULL) {
        entry->tag = android_lookupEventTag(map, tagIndex);
    } else {
        entry->tag = NULL;
    }

    /*
     * If we don't have a map, or didn't find the tag number in the map,
     * stuff a generated tag value into the start of the output buffer and
     * shift the buffer pointers down.
     */
    if (entry->tag == NULL) {
        int tagLen;

        tagLen = snprintf(messageBuf, messageBufLen, "[%d]", tagIndex);
        entry->tag = messageBuf;
        messageBuf += tagLen+1;
        messageBufLen -= tagLen+1;
    }

    /*
     * Format the event log data into the buffer.
     */
    char* outBuf = messageBuf;
    size_t outRemaining = messageBufLen-1;      /* leave one for nul byte */
    int result;
    result = android_log_printBinaryEvent(&eventData, &inCount, &outBuf,
                &outRemaining);
    if (result < 0) {
        fprintf(stderr, "Binary log entry conversion failed\n");
        return -1;
    } else if (result == 1) {
        if (outBuf > messageBuf) {
            /* leave an indicator */
            *(outBuf-1) = '!';
        } else {
            /* no room to output anything at all */
            *outBuf++ = '!';
            outRemaining--;
        }
        /* pretend we ate all the data */
        inCount = 0;
    }

    /* eat the silly terminating '\n' */
    if (inCount == 1 && *eventData == '\n') {
        eventData++;
        inCount--;
    }

    if (inCount != 0) {
        fprintf(stderr,
            "Warning: leftover binary log data (%zu bytes)\n", inCount);
    }

    /*
     * Terminate the buffer.  The NUL byte does not count as part of
     * entry->messageLen.
     */
    *outBuf = '\0';
    entry->messageLen = outBuf - messageBuf;
    assert(entry->messageLen == (messageBufLen-1) - outRemaining);

    entry->message = messageBuf;

    return 0;
}

/**
 * Formats a log message into a buffer
 *
 * Uses defaultBuffer if it can, otherwise malloc()'s a new buffer
 * If return value != defaultBuffer, caller must call free()
 * Returns NULL on malloc error
 */

char *android_log_formatLogLine (
    AndroidLogFormat *p_format,
    char *defaultBuffer,
    size_t defaultBufferSize,
    const AndroidLogEntry *entry,
    size_t *p_outLength)
{
#if defined(HAVE_LOCALTIME_R)
    struct tm tmBuf;
#endif
    struct tm* ptm;
    char timeBuf[32];
    char headerBuf[128];
    char prefixBuf[128], suffixBuf[128];
    char priChar;
    int prefixSuffixIsHeaderFooter = 0;
    char * ret = NULL;

    priChar = filterPriToChar(entry->priority);

    /*
     * 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(&(entry->tv_sec), &tmBuf);
#else
    ptm = localtime(&(entry->tv_sec));
#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 (p_format->format) {
        case FORMAT_TAG:
            prefixLen = snprintf(prefixBuf, sizeof(prefixBuf),
                "%c/%-8s: ", priChar, entry->tag);
            strcpy(suffixBuf, "\n"); suffixLen = 1;
            break;
        case FORMAT_PROCESS:
            prefixLen = snprintf(prefixBuf, sizeof(prefixBuf),
                "%c(%5d) ", priChar, entry->pid);
            suffixLen = snprintf(suffixBuf, sizeof(suffixBuf),
                "  (%s)\n", entry->tag);
            break;
        case FORMAT_THREAD:
            prefixLen = snprintf(prefixBuf, sizeof(prefixBuf),
                "%c(%5d:%5d) ", priChar, entry->pid, entry->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.%03ld %c/%-8s(%5d): ", timeBuf, entry->tv_nsec / 1000000,
                priChar, entry->tag, entry->pid);
            strcpy(suffixBuf, "\n");
            suffixLen = 1;
            break;
        case FORMAT_THREADTIME:
            prefixLen = snprintf(prefixBuf, sizeof(prefixBuf),
                "%s.%03ld %5d %5d %c %-8s: ", timeBuf, entry->tv_nsec / 1000000,
                entry->pid, entry->tid, priChar, entry->tag);
            strcpy(suffixBuf, "\n");
            suffixLen = 1;
            break;
        case FORMAT_LONG:
            prefixLen = snprintf(prefixBuf, sizeof(prefixBuf),
                "[ %s.%03ld %5d:%5d %c/%-8s ]\n",
                timeBuf, entry->tv_nsec / 1000000, entry->pid,
                entry->tid, priChar, entry->tag);
            strcpy(suffixBuf, "\n\n");
            suffixLen = 2;
            prefixSuffixIsHeaderFooter = 1;
            break;
        case FORMAT_BRIEF:
        default:
            prefixLen = snprintf(prefixBuf, sizeof(prefixBuf),
                "%c/%-8s(%5d): ", priChar, entry->tag, entry->pid);
            strcpy(suffixBuf, "\n");
            suffixLen = 1;
            break;
    }
    /* snprintf has a weird return value.   It returns what would have been
     * written given a large enough buffer.  In the case that the prefix is
     * longer then our buffer(128), it messes up the calculations below
     * possibly causing heap corruption.  To avoid this we double check and
     * set the length at the maximum (size minus null byte)
     */
    if(prefixLen >= sizeof(prefixBuf))
        prefixLen = sizeof(prefixBuf) - 1;
    if(suffixLen >= sizeof(suffixBuf))
        suffixLen = sizeof(suffixBuf) - 1;

    /* the following code is tragically unreadable */

    size_t numLines;
    size_t i;
    char *p;
    size_t bufferSize;
    const char *pm;

    if (prefixSuffixIsHeaderFooter) {
        // we're just wrapping message with a header/footer
        numLines = 1;
    } else {
        pm = entry->message;
        numLines = 0;

        // The line-end finding here must match the line-end finding
        // in for ( ... numLines...) loop below
        while (pm < (entry->message + entry->messageLen)) {
            if (*pm++ == '\n') numLines++;
        }
        // plus one line for anything not newline-terminated at the end
        if (pm > entry->message && *(pm-1) != '\n') numLines++;
    }

    // this is an upper bound--newlines in message may be counted
    // extraneously
    bufferSize = (numLines * (prefixLen + suffixLen)) + entry->messageLen + 1;

    if (defaultBufferSize >= bufferSize) {
        ret = defaultBuffer;
    } else {
        ret = (char *)malloc(bufferSize);

        if (ret == NULL) {
            return ret;
        }
    }

    ret[0] = '\0';       /* to start strcat off */

    p = ret;
    pm = entry->message;

    if (prefixSuffixIsHeaderFooter) {
        strcat(p, prefixBuf);
        p += prefixLen;
        strncat(p, entry->message, entry->messageLen);
        p += entry->messageLen;
        strcat(p, suffixBuf);
        p += suffixLen;
    } else {
        while(pm < (entry->message + entry->messageLen)) {
            const char *lineStart;
            size_t lineLen;
            lineStart = pm;

            // Find the next end-of-line in message
            while (pm < (entry->message + entry->messageLen)
                    && *pm != '\n') pm++;
            lineLen = pm - lineStart;

            strcat(p, prefixBuf);
            p += prefixLen;
            strncat(p, lineStart, lineLen);
            p += lineLen;
            strcat(p, suffixBuf);
            p += suffixLen;

            if (*pm == '\n') pm++;
        }
    }

    if (p_outLength != NULL) {
        *p_outLength = p - ret;
    }

    return ret;
}

/**
 * Either print or do not print log line, based on filter
 *
 * Returns count bytes written
 */

int android_log_printLogLine(
    AndroidLogFormat *p_format,
    int fd,
    const AndroidLogEntry *entry)
{
    int ret;
    char defaultBuffer[512];
    char *outBuffer = NULL;
    size_t totalLen;

    outBuffer = android_log_formatLogLine(p_format, defaultBuffer,
            sizeof(defaultBuffer), entry, &totalLen);

    if (!outBuffer)
        return -1;

    do {
        ret = write(fd, outBuffer, totalLen);
    } while (ret < 0 && errno == EINTR);

    if (ret < 0) {
        fprintf(stderr, "+++ LOG: write failed (errno=%d)\n", errno);
        ret = 0;
        goto done;
    }

    if (((size_t)ret) < totalLen) {
        fprintf(stderr, "+++ LOG: write partial (%d of %d)\n", ret,
                (int)totalLen);
        goto done;
    }

done:
    if (outBuffer != defaultBuffer) {
        free(outBuffer);
    }

    return ret;
}