Training courses

Kernel and Embedded Linux

Bootlin training courses

Embedded Linux, kernel,
Yocto Project, Buildroot, real-time,
graphics, boot time, debugging...

Bootlin logo

Elixir Cross Referencer

  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
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
/*	$NetBSD: makeshell.c,v 1.9 2020/05/25 20:47:34 christos Exp $	*/


/**
 * \file makeshell.c
 *
 *  This module will interpret the options set in the tOptions
 *  structure and create a Bourne shell script capable of parsing them.
 *
 * @addtogroup autoopts
 * @{
 */
/*
 *  This file is part of AutoOpts, a companion to AutoGen.
 *  AutoOpts is free software.
 *  AutoOpts is Copyright (C) 1992-2015 by Bruce Korb - all rights reserved
 *
 *  AutoOpts is available under any one of two licenses.  The license
 *  in use must be one of these two and the choice is under the control
 *  of the user of the license.
 *
 *   The GNU Lesser General Public License, version 3 or later
 *      See the files "COPYING.lgplv3" and "COPYING.gplv3"
 *
 *   The Modified Berkeley Software Distribution License
 *      See the file "COPYING.mbsd"
 *
 *  These files have the following sha256 sums:
 *
 *  8584710e9b04216a394078dc156b781d0b47e1729104d666658aecef8ee32e95  COPYING.gplv3
 *  4379e7444a0e2ce2b12dd6f5a52a27a4d02d39d247901d3285c88cf0d37f477b  COPYING.lgplv3
 *  13aa749a5b0a454917a944ed8fffc530b784f5ead522b1aacaf4ec8aa55a6239  COPYING.mbsd
 */

 static inline unsigned char to_uchar (char ch) { return ch; }

#define UPPER(_c) (toupper(to_uchar(_c)))
#define LOWER(_c) (tolower(to_uchar(_c)))

/* = = = START-STATIC-FORWARD = = = */
static void
emit_var_text(char const * prog, char const * var, int fdin);

static void
text_to_var(tOptions * opts, teTextTo which, tOptDesc * od);

static void
emit_usage(tOptions * opts);

static void
emit_wrapup(tOptions * opts);

static void
emit_setup(tOptions * opts);

static void
emit_action(tOptions * opts, tOptDesc * od);

static void
emit_inaction(tOptions * opts, tOptDesc * od);

static void
emit_flag(tOptions * opts);

static void
emit_match_expr(char const * name, tOptDesc * cod, tOptions * opts);

static void
emit_long(tOptions * opts);

static char *
load_old_output(char const * fname, char const * pname);

static void
open_out(char const * fname, char const * pname);
/* = = = END-STATIC-FORWARD = = = */

LOCAL noreturn void
option_exits(int exit_code)
{
    if (print_exit)
        printf("\nexit %d\n", exit_code);
    exit(exit_code);
}

LOCAL noreturn void
ao_bug(char const * msg)
{
    fprintf(stderr, zao_bug_msg, msg);
    option_exits(EX_SOFTWARE);
}

LOCAL void
fserr_warn(char const * prog, char const * op, char const * fname)
{
    fprintf(stderr, zfserr_fmt, prog, errno, strerror(errno),
            op, fname);
}

LOCAL noreturn void
fserr_exit(char const * prog, char const * op, char const * fname)
{
    fserr_warn(prog, op, fname);
    option_exits(EXIT_FAILURE);
}

/*=export_func  optionParseShell
 * private:
 *
 * what:  Decipher a boolean value
 * arg:   + tOptions * + pOpts    + program options descriptor +
 *
 * doc:
 *  Emit a shell script that will parse the command line options.
=*/
void
optionParseShell(tOptions * opts)
{
    /*
     *  Check for our SHELL option now.
     *  IF the output file contains the "#!" magic marker,
     *  it will override anything we do here.
     */
    if (HAVE_GENSHELL_OPT(SHELL))
        shell_prog = GENSHELL_OPT_ARG(SHELL);

    else if (! ENABLED_GENSHELL_OPT(SHELL))
        shell_prog = NULL;

    else if ((shell_prog = getenv("SHELL")),
             shell_prog == NULL)

        shell_prog = POSIX_SHELL;

    /*
     *  Check for a specified output file
     */
    if (HAVE_GENSHELL_OPT(SCRIPT))
        open_out(GENSHELL_OPT_ARG(SCRIPT), opts->pzProgName);
    
    emit_usage(opts);
    emit_setup(opts);

    /*
     *  There are four modes of option processing.
     */
    switch (opts->fOptSet & (OPTPROC_LONGOPT|OPTPROC_SHORTOPT)) {
    case OPTPROC_LONGOPT:
        fputs(LOOP_STR,         stdout);

        fputs(LONG_OPT_MARK,    stdout);
        fputs(INIT_LOPT_STR,    stdout);
        emit_long(opts);
        printf(LOPT_ARG_FMT,    opts->pzPROGNAME);
        fputs(END_OPT_SEL_STR,  stdout);

        fputs(NOT_FOUND_STR,    stdout);
        break;

    case 0:
        fputs(ONLY_OPTS_LOOP,   stdout);
        fputs(INIT_LOPT_STR,    stdout);
        emit_long(opts);
        printf(LOPT_ARG_FMT,    opts->pzPROGNAME);
        break;

    case OPTPROC_SHORTOPT:
        fputs(LOOP_STR,         stdout);

        fputs(FLAG_OPT_MARK,    stdout);
        fputs(INIT_OPT_STR,     stdout);
        emit_flag(opts);
        printf(OPT_ARG_FMT,     opts->pzPROGNAME);
        fputs(END_OPT_SEL_STR,  stdout);

        fputs(NOT_FOUND_STR,    stdout);
        break;

    case OPTPROC_LONGOPT|OPTPROC_SHORTOPT:
        fputs(LOOP_STR,         stdout);

        fputs(LONG_OPT_MARK,    stdout);
        fputs(INIT_LOPT_STR,    stdout);
        emit_long(opts);
        printf(LOPT_ARG_FMT,    opts->pzPROGNAME);
        fputs(END_OPT_SEL_STR,  stdout);

        fputs(FLAG_OPT_MARK,    stdout);
        fputs(INIT_OPT_STR,     stdout);
        emit_flag(opts);
        printf(OPT_ARG_FMT,     opts->pzPROGNAME);
        fputs(END_OPT_SEL_STR,  stdout);

        fputs(NOT_FOUND_STR,    stdout);
        break;
    }

    emit_wrapup(opts);
    if ((script_trailer != NULL) && (*script_trailer != NUL))
        fputs(script_trailer, stdout);
    else if (ENABLED_GENSHELL_OPT(SHELL))
        printf(SHOW_PROG_ENV, opts->pzPROGNAME);

#ifdef HAVE_FCHMOD
    fchmod(STDOUT_FILENO, 0755);
#endif
    fclose(stdout);

    if (ferror(stdout))
        fserr_exit(opts->pzProgName, zwriting, zstdout_name);

    AGFREE(script_text);
    script_leader    = NULL;
    script_trailer   = NULL;
    script_text      = NULL;
}

#ifdef HAVE_WORKING_FORK
/**
 * Print the value of "var" to a file descriptor.
 * The "fdin" is the read end of a pipe to a forked process that
 * is writing usage text to it.  We read that text in and re-emit
 * to standard out, formatting it so that it is assigned to a
 * shell variable.
 *
 * @param[in] prog  The capitalized, c-variable-formatted program name
 * @param[in] var   a similarly formatted type name
 *                  (LONGUSAGE, USAGE or VERSION)
 * @param[in] fdin  the input end of a pipe
 */
static void
emit_var_text(char const * prog, char const * var, int fdin)
{
    FILE * fp   = fdopen(fdin, "r" FOPEN_BINARY_FLAG);
    int    nlct = 0; /* defer newlines and skip trailing ones */

    printf(SET_TEXT_FMT, prog, var);
    if (fp == NULL)
        goto skip_text;

    for (;;) {
        int  ch = fgetc(fp);
        switch (ch) {

        case NL:
            nlct++;
            break;

        case '\'':
            while (nlct > 0) {
                fputc(NL, stdout);
                nlct--;
            }
            fputs(apostrophe, stdout);
            break;

        case EOF:
            goto done;

        default:
            while (nlct > 0) {
                fputc(NL, stdout);
                nlct--;
            }
            fputc(ch, stdout);
            break;
        }
    } done:;

    fclose(fp);

 skip_text:

    fputs(END_SET_TEXT, stdout);
}
#endif

/**
 *  The purpose of this function is to assign "long usage", short usage
 *  and version information to a shell variable.  Rather than wind our
 *  way through all the logic necessary to emit the text directly, we
 *  fork(), have our child process emit the text the normal way and
 *  capture the output in the parent process.
 *
 * @param[in] opts  the program options
 * @param[in] which what to print: long usage, usage or version
 * @param[in] od    for TT_VERSION, it is the version option
 */
static void
text_to_var(tOptions * opts, teTextTo which, tOptDesc * od)
{
#   define _TT_(n) static char const z ## n [] = #n;
    TEXTTO_TABLE
#   undef _TT_
#   define _TT_(n) z ## n ,
      static char const * ttnames[] = { TEXTTO_TABLE };
#   undef _TT_

#if ! defined(HAVE_WORKING_FORK)
    printf(SET_NO_TEXT_FMT, opts->pzPROGNAME, ttnames[which]);
#else
    int  fdpair[2];

    fflush(stdout);
    fflush(stderr);

    if (pipe(fdpair) != 0)
        fserr_exit(opts->pzProgName, "pipe", zinter_proc_pipe);

    switch (fork()) {
    case -1:
        fserr_exit(opts->pzProgName, "fork", opts->pzProgName);
        /* NOTREACHED */

    case 0:
        /*
         * Send both stderr and stdout to the pipe.  No matter which
         * descriptor is used, we capture the output on the read end.
         */
        dup2(fdpair[1], STDERR_FILENO);
        dup2(fdpair[1], STDOUT_FILENO);
        close(fdpair[0]);

        switch (which) {
        case TT_LONGUSAGE:
            (*(opts->pUsageProc))(opts, EXIT_SUCCESS);
            /* NOTREACHED */

        case TT_USAGE:
            (*(opts->pUsageProc))(opts, EXIT_FAILURE);
            /* NOTREACHED */

        case TT_VERSION:
            if (od->fOptState & OPTST_ALLOC_ARG) {
                AGFREE(od->optArg.argString);
                od->fOptState &= ~OPTST_ALLOC_ARG;
            }
            od->optArg.argString = "c";
            optionPrintVersion(opts, od);
            /* NOTREACHED */

        default:
            option_exits(EXIT_FAILURE);
            /* NOTREACHED */
        }
        /* NOTREACHED */

    default:
        close(fdpair[1]);
    }

    emit_var_text(opts->pzPROGNAME, ttnames[which], fdpair[0]);
#endif
}

/**
 * capture usage text in shell variables.
 * 
 */
static void
emit_usage(tOptions * opts)
{
    char tm_nm_buf[AO_NAME_SIZE];

    /*
     *  First, switch stdout to the output file name.
     *  Then, change the program name to the one defined
     *  by the definitions (rather than the current
     *  executable name).  Down case the upper cased name.
     */
    if (script_leader != NULL)
        fputs(script_leader, stdout);

    {
        char const * out_nm;

        {
            time_t    c_tim = time(NULL);
            struct tm * ptm = localtime(&c_tim);
            strftime(tm_nm_buf, AO_NAME_SIZE, TIME_FMT, ptm );
        }

        if (HAVE_GENSHELL_OPT(SCRIPT))
             out_nm = GENSHELL_OPT_ARG(SCRIPT);
        else out_nm = STDOUT;

        if ((script_leader == NULL) && (shell_prog != NULL))
            printf(SHELL_MAGIC, shell_prog);

        printf(PREAMBLE_FMT, START_MARK, out_nm, tm_nm_buf);
    }

    printf(END_PRE_FMT, opts->pzPROGNAME);

    /*
     *  Get a copy of the original program name in lower case and
     *  fill in an approximation of the program name from it.
     */
    {
        char *       pzPN = tm_nm_buf;
        char const * pz   = opts->pzPROGNAME;
        char **      pp;

        /* Copy the program name into the time/name buffer */
        for (;;) {
            if ((*pzPN++ = (char)tolower((unsigned char)*pz++)) == NUL)
                break;
        }

        pp  = VOIDP(&(opts->pzProgPath));
        *pp = tm_nm_buf;
        pp  = VOIDP(&(opts->pzProgName));
        *pp = tm_nm_buf;
    }

    text_to_var(opts, TT_LONGUSAGE, NULL);
    text_to_var(opts, TT_USAGE,     NULL);

    {
        tOptDesc * pOptDesc = opts->pOptDesc;
        int        optionCt = opts->optCt;

        for (;;) {
            if (pOptDesc->pOptProc == optionPrintVersion) {
                text_to_var(opts, TT_VERSION, pOptDesc);
                break;
            }

            if (--optionCt <= 0)
                break;
            pOptDesc++;
        }
    }
}

static void
emit_wrapup(tOptions * opts)
{
    tOptDesc *   od     = opts->pOptDesc;
    int          opt_ct = opts->presetOptCt;
    char const * fmt;

    printf(FINISH_LOOP, opts->pzPROGNAME);
    for (;opt_ct > 0; od++, --opt_ct) {
        /*
         *  Options that are either usage documentation or are compiled out
         *  are not to be processed.
         */
        if (SKIP_OPT(od) || (od->pz_NAME == NULL))
            continue;

        /*
         *  do not presence check if there is no minimum/must-set
         */
        if ((od->optMinCt == 0) && ((od->fOptState & OPTST_MUST_SET) == 0))
            continue;

        if (od->optMaxCt > 1)
             fmt = CHK_MIN_COUNT;
        else fmt = CHK_ONE_REQUIRED;

        {
            int min = (od->optMinCt == 0) ? 1 : od->optMinCt;
            printf(fmt, opts->pzPROGNAME, od->pz_NAME, min);
        }
    }
    fputs(END_MARK, stdout);
}

static void
emit_setup(tOptions * opts)
{
    tOptDesc *   od     = opts->pOptDesc;
    int          opt_ct = opts->presetOptCt;
    char const * fmt;
    char const * def_val;

    for (;opt_ct > 0; od++, --opt_ct) {
        char int_val_buf[32];

        /*
         *  Options that are either usage documentation or are compiled out
         *  are not to be processed.
         */
        if (SKIP_OPT(od) || (od->pz_NAME == NULL))
            continue;

        if (od->optMaxCt > 1)
             fmt = MULTI_DEF_FMT;
        else fmt = SGL_DEF_FMT;

        /*
         *  IF this is an enumeration/bitmask option, then convert the value
         *  to a string before printing the default value.
         */
        switch (OPTST_GET_ARGTYPE(od->fOptState)) {
        case OPARG_TYPE_ENUMERATION:
            (*(od->pOptProc))(OPTPROC_EMIT_SHELL, od );
            def_val = od->optArg.argString;
            break;

        /*
         *  Numeric and membership bit options are just printed as a number.
         */
        case OPARG_TYPE_NUMERIC:
            snprintf(int_val_buf, sizeof(int_val_buf), "%d",
                     (int)od->optArg.argInt);
            def_val = int_val_buf;
            break;

        case OPARG_TYPE_MEMBERSHIP:
            snprintf(int_val_buf, sizeof(int_val_buf), "%lu",
                     (unsigned long)od->optArg.argIntptr);
            def_val = int_val_buf;
            break;

        case OPARG_TYPE_BOOLEAN:
            def_val = (od->optArg.argBool) ? TRUE_STR : FALSE_STR;
            break;

        default:
            if (od->optArg.argString == NULL) {
                if (fmt == SGL_DEF_FMT)
                    fmt = SGL_NO_DEF_FMT;
                def_val = NULL;
            }
            else
                def_val = od->optArg.argString;
        }

        printf(fmt, opts->pzPROGNAME, od->pz_NAME, def_val);
    }
}

static void
emit_action(tOptions * opts, tOptDesc * od)
{
    if (od->pOptProc == optionPrintVersion)
        printf(ECHO_N_EXIT, opts->pzPROGNAME, VER_STR);

    else if (od->pOptProc == optionPagedUsage)
        printf(PAGE_USAGE_TEXT, opts->pzPROGNAME);

    else if (od->pOptProc == optionLoadOpt) {
        printf(LVL3_CMD, NO_LOAD_WARN);
        printf(LVL3_CMD, YES_NEED_OPT_ARG);

    } else if (od->pz_NAME == NULL) {

        if (od->pOptProc == NULL) {
            printf(LVL3_CMD, NO_SAVE_OPTS);
            printf(LVL3_CMD, OK_NEED_OPT_ARG);
        } else
            printf(ECHO_N_EXIT, opts->pzPROGNAME, LONG_USE_STR);

    } else {
        if (od->optMaxCt == 1)
            printf(SGL_ARG_FMT, opts->pzPROGNAME, od->pz_NAME);
        else {
            if ((unsigned)od->optMaxCt < NOLIMIT)
                printf(CHK_MAX_COUNT, opts->pzPROGNAME,
                       od->pz_NAME, od->optMaxCt);

            printf(MULTI_ARG_FMT, opts->pzPROGNAME, od->pz_NAME);
        }

        /*
         *  Fix up the args.
         */
        if (OPTST_GET_ARGTYPE(od->fOptState) == OPARG_TYPE_NONE) {
            printf(SET_MULTI_ARG, opts->pzPROGNAME, od->pz_NAME);
            printf(LVL3_CMD, NO_ARG_NEEDED);

        } else if (od->fOptState & OPTST_ARG_OPTIONAL) {
            printf(SET_MULTI_ARG,  opts->pzPROGNAME, od->pz_NAME);
            printf(LVL3_CMD, OK_NEED_OPT_ARG);

        } else {
            printf(LVL3_CMD, YES_NEED_OPT_ARG);
        }
    }
    fputs(zOptionEndSelect, stdout);
}

static void
emit_inaction(tOptions * opts, tOptDesc * od)
{
    if (od->pOptProc == optionLoadOpt) {
        printf(LVL3_CMD, NO_SUPPRESS_LOAD);

    } else if (od->optMaxCt == 1)
        printf(NO_SGL_ARG_FMT, opts->pzPROGNAME,
               od->pz_NAME, od->pz_DisablePfx);
    else
        printf(NO_MULTI_ARG_FMT, opts->pzPROGNAME,
               od->pz_NAME, od->pz_DisablePfx);

    printf(LVL3_CMD, NO_ARG_NEEDED);
    fputs(zOptionEndSelect, stdout);
}

/**
 * recognize flag options.  These go at the end.
 * At the end, emit code to handle options we don't recognize.
 *
 * @param[in] opts  the program options
 */
static void
emit_flag(tOptions * opts)
{
    tOptDesc * od = opts->pOptDesc;
    int        opt_ct = opts->optCt;

    fputs(zOptionCase, stdout);

    for (;opt_ct > 0; od++, --opt_ct) {

        if (SKIP_OPT(od) || ! IS_GRAPHIC_CHAR(od->optValue))
            continue;

        printf(zOptionFlag, od->optValue);
        emit_action(opts, od);
    }
    printf(UNK_OPT_FMT, FLAG_STR, opts->pzPROGNAME);
}

/**
 *  Emit the match text for a long option.  The passed in \a name may be
 *  either the enablement name or the disablement name.
 *
 * @param[in] name  The current name to check.
 * @param[in] cod   current option descriptor
 * @param[in] opts  the program options
 */
static void
emit_match_expr(char const * name, tOptDesc * cod, tOptions * opts)
{
    char name_bf[32];
    unsigned int    min_match_ct = 2;
    unsigned int    max_match_ct = strlen(name) - 1;

    if (max_match_ct >= sizeof(name_bf) - 1)
        goto leave;
    
    {
        tOptDesc *  od = opts->pOptDesc;
        int         ct = opts->optCt;

        for (; ct-- > 0; od++) {
            unsigned int match_ct = 0;

            /*
             *  Omit the current option, Doc opts and compiled out opts.
             */
            if ((od == cod) || SKIP_OPT(od))
                continue;

            /*
             *  Check each character of the name case insensitively.
             *  They must not be the same.  They cannot be, because it would
             *  not compile correctly if they were.
             */
            while (UPPER(od->pz_Name[match_ct]) == UPPER(name[match_ct]))
                match_ct++;

            if (match_ct > min_match_ct)
                min_match_ct = match_ct;

            /*
             *  Check the disablement name, too.
             */
            if (od->pz_DisableName == NULL)
                continue;

            match_ct = 0;
            while (  toupper((unsigned char)od->pz_DisableName[match_ct])
                  == toupper((unsigned char)name[match_ct]))
                match_ct++;
            if (match_ct > min_match_ct)
                min_match_ct = match_ct;
        }
    }

    /*
     *  Don't bother emitting partial matches if there is only one possible
     *  partial match.
     */
    if (min_match_ct < max_match_ct) {
        char *  pz    = name_bf + min_match_ct;
        int     nm_ix = min_match_ct;

        memcpy(name_bf, name, min_match_ct);

        for (;;) {
            *pz = NUL;
            printf(zOptionPartName, name_bf);
            *pz++ = name[nm_ix++];
            if (name[nm_ix] == NUL) {
                *pz = NUL;
                break;
            }
        }
    }

leave:
    printf(zOptionFullName, name);
}

/**
 *  Emit GNU-standard long option handling code.
 *
 * @param[in] opts  the program options
 */
static void
emit_long(tOptions * opts)
{
    tOptDesc * od = opts->pOptDesc;
    int        ct  = opts->optCt;

    fputs(zOptionCase, stdout);

    /*
     *  do each option, ...
     */
    do  {
        /*
         *  Documentation & compiled-out options
         */
        if (SKIP_OPT(od))
            continue;

        emit_match_expr(od->pz_Name, od, opts);
        emit_action(opts, od);

        /*
         *  Now, do the same thing for the disablement version of the option.
         */
        if (od->pz_DisableName != NULL) {
            emit_match_expr(od->pz_DisableName, od, opts);
            emit_inaction(opts, od);
        }
    } while (od++, --ct > 0);

    printf(UNK_OPT_FMT, OPTION_STR, opts->pzPROGNAME);
}

/**
 * Load the previous shell script output file.  We need to preserve any
 * hand-edited additions outside of the START_MARK and END_MARKs.
 *
 * @param[in] fname  the output file name
 */
static char *
load_old_output(char const * fname, char const * pname)
{
    /*
     *  IF we cannot stat the file,
     *  THEN assume we are creating a new file.
     *       Skip the loading of the old data.
     */
    FILE * fp = fopen(fname, "r" FOPEN_BINARY_FLAG);
    struct stat stbf;
    char * text;
    char * scan;

    if (fp == NULL)
        return NULL;

    /*
     * If we opened it, we should be able to stat it and it needs
     * to be a regular file
     */
    if ((fstat(fileno(fp), &stbf) != 0) || (! S_ISREG(stbf.st_mode)))
        fserr_exit(pname, "fstat", fname);

    scan = text = AGALOC(stbf.st_size + 1, "f data");

    /*
     *  Read in all the data as fast as our OS will let us.
     */
    for (;;) {
        size_t inct = fread(VOIDP(scan), 1, (size_t)stbf.st_size, fp);
        if (inct == 0)
            break;

        stbf.st_size -= (ssize_t)inct;

        if (stbf.st_size == 0)
            break;

        scan += inct;
    }

    *scan = NUL;
    fclose(fp);

    return text;
}

/**
 * Open the specified output file.  If it already exists, load its
 * contents and save the non-generated (hand edited) portions.
 * If a "start mark" is found, everything before it is preserved leader.
 * If not, the entire thing is a trailer.  Assuming the start is found,
 * then everything after the end marker is the trailer.  If the end
 * mark is not found, the file is actually corrupt, but we take the
 * remainder to be the trailer.
 *
 * @param[in] fname  the output file name
 */
static void
open_out(char const * fname, char const * pname)
{

    do  {
        char * txt = script_text = load_old_output(fname, pname);
        char * scn;

        if (txt == NULL)
            break;

        scn = strstr(txt, START_MARK);
        if (scn == NULL) {
            script_trailer = txt;
            break;
        }

        *(scn++) = NUL;
        scn = strstr(scn, END_MARK);
        if (scn == NULL) {
            /*
             * The file is corrupt.  Set the trailer to be everything
             * after the start mark. The user will need to fix it up.
             */
            script_trailer = txt + strlen(txt) + START_MARK_LEN + 1;
            break;
        }

        /*
         *  Check to see if the data contains our marker.
         *  If it does, then we will skip over it
         */
        script_trailer = scn + END_MARK_LEN;
        script_leader  = txt;
    } while (false);

    if (freopen(fname, "w" FOPEN_BINARY_FLAG, stdout) != stdout)
        fserr_exit(pname, "freopen", fname);
}

/*=export_func genshelloptUsage
 * private:
 * what: The usage function for the genshellopt generated program
 *
 * arg:  + tOptions * + opts    + program options descriptor +
 * arg:  + int        + exit_cd + usage text type to produce +
 *
 * doc:
 *  This function is used to create the usage strings for the option
 *  processing shell script code.  Two child processes are spawned
 *  each emitting the usage text in either the short (error exit)
 *  style or the long style.  The generated program will capture this
 *  and create shell script variables containing the two types of text.
=*/
void
genshelloptUsage(tOptions * opts, int exit_cd)
{
#if ! defined(HAVE_WORKING_FORK)
    optionUsage(opts, exit_cd);
#else
    /*
     *  IF not EXIT_SUCCESS,
     *  THEN emit the short form of usage.
     */
    if (exit_cd != EXIT_SUCCESS)
        optionUsage(opts, exit_cd);
    fflush(stderr);
    fflush(stdout);
    if (ferror(stdout) || ferror(stderr))
        option_exits(EXIT_FAILURE);

    option_usage_fp = stdout;

    /*
     *  First, print our usage
     */
    switch (fork()) {
    case -1:
        optionUsage(opts, EXIT_FAILURE);
        /* NOTREACHED */

    case 0:
        pagerState = PAGER_STATE_CHILD;
        optionUsage(opts, EXIT_SUCCESS);
        /* NOTREACHED */
        _exit(EXIT_FAILURE);

    default:
    {
        int  sts;
        wait(&sts);
    }
    }

    /*
     *  Generate the pzProgName, since optionProcess() normally
     *  gets it from the command line
     */
    {
        char *  pz;
        char ** pp = VOIDP(&(optionParseShellOptions->pzProgName));
        AGDUPSTR(pz, optionParseShellOptions->pzPROGNAME, "prog name");
        *pp = pz;
        while (*pz != NUL) {
            *pz = (char)LOWER(*pz);
            pz++;
        }
    }

    /*
     *  Separate the makeshell usage from the client usage
     */
    fprintf(option_usage_fp, zGenshell, optionParseShellOptions->pzProgName);
    fflush(option_usage_fp);

    /*
     *  Now, print the client usage.
     */
    switch (fork()) {
    case 0:
        pagerState = PAGER_STATE_CHILD;
        /*FALLTHROUGH*/
    case -1:
        optionUsage(optionParseShellOptions, EXIT_FAILURE);

    default:
    {
        int  sts;
        wait(&sts);
    }
    }

    fflush(stdout);
    if (ferror(stdout))
        fserr_exit(opts->pzProgName, zwriting, zstdout_name);

    option_exits(EXIT_SUCCESS);
#endif
}

/** @}
 *
 * Local Variables:
 * mode: C
 * c-file-style: "stroustrup"
 * indent-tabs-mode: nil
 * End:
 * end of autoopts/makeshell.c */