summaryrefslogtreecommitdiff
path: root/backend/escl/escl.c
blob: c40fd985f661ac343897a9cc5840175b0ac280db (plain)
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
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
/* sane - Scanner Access Now Easy.

   Copyright (C) 2019 Touboul Nathane
   Copyright (C) 2019 Thierry HUCHARD <thierry@ordissimo.com>

   This file is part of the SANE package.

   SANE is free software; you can redistribute it and/or modify it under
   the terms of the GNU General Public License as published by the Free
   Software Foundation; either version 3 of the License, or (at your
   option) any later version.

   SANE is distributed in the hope that it will be useful, but WITHOUT
   ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
   FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
   for more details.

   You should have received a copy of the GNU General Public License
   along with sane; see the file COPYING.  If not, write to the Free
   Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

   This file implements a SANE backend for eSCL scanners.  */

#include "escl.h"

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include <setjmp.h>

#include <curl/curl.h>

#include "../include/sane/saneopts.h"
#include "../include/sane/sanei.h"
#include "../include/sane/sanei_backend.h"
#include "../include/sane/sanei_config.h"

#define min(A,B) (((A)<(B)) ? (A) : (B))
#define max(A,B) (((A)>(B)) ? (A) : (B))
#define INPUT_BUFFER_SIZE 4096

static const SANE_Device **devlist = NULL;
static ESCL_Device *list_devices_primary = NULL;
static int num_devices = 0;

typedef struct Handled {
    struct Handled *next;
    ESCL_Device *device;
    char *result;
    ESCL_ScanParam param;
    SANE_Option_Descriptor opt[NUM_OPTIONS];
    Option_Value val[NUM_OPTIONS];
    capabilities_t *scanner;
    SANE_Range x_range1;
    SANE_Range x_range2;
    SANE_Range y_range1;
    SANE_Range y_range2;
    SANE_Bool cancel;
    SANE_Bool write_scan_data;
    SANE_Bool decompress_scan_data;
    SANE_Bool end_read;
    SANE_Parameters ps;
} escl_sane_t;

static ESCL_Device *
escl_free_device(ESCL_Device *current)
{
    if (!current) return NULL;
    free((void*)current->ip_address);
    free((void*)current->model_name);
    free((void*)current->type);
    free(current->unix_socket);
    free(current);
    return NULL;
}

void
escl_free_handler(escl_sane_t *handler)
{
    if (handler == NULL)
        return;

    escl_free_device(handler->device);
    free(handler);
}

SANE_Status escl_parse_name(SANE_String_Const name, ESCL_Device *device);

static SANE_Status
escl_check_and_add_device(ESCL_Device *current)
{
    if(!current) {
      DBG (10, "ESCL_Device *current us null.\n");
      return (SANE_STATUS_NO_MEM);
    }
    if (!current->ip_address) {
      DBG (10, "Ip Address allocation failure.\n");
      return (SANE_STATUS_NO_MEM);
    }
    if (current->port_nb == 0) {
      DBG (10, "No port defined.\n");
      return (SANE_STATUS_NO_MEM);
    }
    if (!current->model_name) {
      DBG (10, "Modele Name allocation failure.\n");
      return (SANE_STATUS_NO_MEM);
    }
    if (!current->type) {
      DBG (10, "Scanner Type allocation failure.\n");
      return (SANE_STATUS_NO_MEM);
    }
    ++num_devices;
    current->next = list_devices_primary;
    list_devices_primary = current;
    return (SANE_STATUS_GOOD);
}

/**
 * \fn static SANE_Status escl_add_in_list(ESCL_Device *current)
 * \brief Function that adds all the element needed to my list :
 *        the port number, the model name, the ip address, and the type of url (http/https).
 *        Moreover, this function counts the number of devices found.
 *
 * \return SANE_STATUS_GOOD if everything is OK.
 */
static SANE_Status
escl_add_in_list(ESCL_Device *current)
{
    if(!current) {
      DBG (10, "ESCL_Device *current us null.\n");
      return (SANE_STATUS_NO_MEM);
    }

    if (SANE_STATUS_GOOD ==
        escl_check_and_add_device(current)) {
        list_devices_primary = current;
        return (SANE_STATUS_GOOD);
    }
    current = escl_free_device(current);
    return (SANE_STATUS_NO_MEM);
}

/**
 * \fn SANE_Status escl_device_add(int port_nb, const char *model_name, char *ip_address, char *type)
 * \brief Function that browses my list ('for' loop) and returns the "escl_add_in_list" function to
 *        adds all the element needed to my list :
 *        the port number, the model name, the ip address and the type of the url (http / https).
 *
 * \return escl_add_in_list(current)
 */
SANE_Status
escl_device_add(int port_nb, const char *model_name, char *ip_address, char *type)
{
    char tmp[PATH_MAX] = { 0 };
    char *model = NULL;
    ESCL_Device *current = NULL;
    DBG (10, "escl_device_add\n");
    for (current = list_devices_primary; current; current = current->next) {
	if (strcmp(current->ip_address, ip_address) == 0)
           {
	      if (strcmp(current->type, type))
                {
                  if(!strcmp(type, "_uscans._tcp") ||
                     !strcmp(type, "https"))
                    {
                       free (current->type);
                       current->type = strdup(type);
                       current->port_nb = port_nb;
                       current->https = SANE_TRUE;
                    }
	          return (SANE_STATUS_GOOD);
                }
              else if (current->port_nb == port_nb)
	        return (SANE_STATUS_GOOD);
           }
    }
    current = (ESCL_Device*)calloc(1, sizeof(*current));
    if (current == NULL) {
       DBG (10, "New device allocation failure.\n");
       return (SANE_STATUS_NO_MEM);
    }
    current->port_nb = port_nb;

    if (strcmp(type, "_uscan._tcp") != 0 && strcmp(type, "http") != 0) {
        snprintf(tmp, sizeof(tmp), "%s SSL", model_name);
        current->https = SANE_TRUE;
    } else {
        current->https = SANE_FALSE;
    }
    model = (char*)(tmp[0] != 0 ? tmp : model_name);
    current->model_name = strdup(model);
    current->ip_address = strdup(ip_address);
    current->type = strdup(type);
    return escl_add_in_list(current);
}

/**
 * \fn static inline size_t max_string_size(const SANE_String_Const strings[])
 * \brief Function that browses the string ('for' loop) and counts the number of character in the string.
 *        --> this allows to know the maximum size of the string.
 *
 * \return max_size + 1 (the size max)
 */
static inline size_t
max_string_size(const SANE_String_Const strings[])
{
    size_t max_size = 0;
    int i = 0;

    for (i = 0; strings[i]; ++i) {
	size_t size = strlen (strings[i]);
	if (size > max_size)
	    max_size = size;
    }
    return (max_size + 1);
}

static char *
get_vendor(char *search)
{
	if(strcasestr(search, "Epson"))
		return strdup("Epson");
	else if(strcasestr(search, "Fujitsu"))
		return strdup("Fujitsu");
	else if(strcasestr(search, "HP"))
		return strdup("HP");
	else if(strcasestr(search, "Canon"))
		return strdup("Canon");
	else if(strcasestr(search, "Lexmark"))
		return strdup("Lexmark");
	else if(strcasestr(search, "Samsung"))
		return strdup("Samsung");
	else if(strcasestr(search, "Xerox"))
		return strdup("Xerox");
	else if(strcasestr(search, "OKI"))
		return strdup("OKI");
	else if(strcasestr(search, "Hewlett Packard"))
		return strdup("Hewlett Packard");
	else if(strcasestr(search, "IBM"))
		return strdup("IBM");
	else if(strcasestr(search, "Mustek"))
		return strdup("Mustek");
	else if(strcasestr(search, "Ricoh"))
		return strdup("Ricoh");
	else if(strcasestr(search, "Sharp"))
		return strdup("Sharp");
	else if(strcasestr(search, "UMAX"))
		return strdup("UMAX");
	else if(strcasestr(search, "PINT"))
		return strdup("PINT");
	else if(strcasestr(search, "Brother"))
		return strdup("Brother");
	return NULL;
}

/**
 * \fn static SANE_Device *convertFromESCLDev(ESCL_Device *cdev)
 * \brief Function that checks if the url of the received scanner is secured or not (http / https).
 *        --> if the url is not secured, our own url will be composed like "http://'ip':'port'".
 *        --> else, our own url will be composed like "https://'ip':'port'".
 *        AND, it's in this function that we gather all the informations of the url (that were in our list) :
 *        the model_name, the port, the ip, and the type of url.
 *        SO, leaving this function, we have in memory the complete url.
 *
 * \return sdev (structure that contains the elements of the url)
 */
static SANE_Device *
convertFromESCLDev(ESCL_Device *cdev)
{
    char *tmp;
    int len, lv = 0;
    char unix_path[PATH_MAX+7] = { 0 };
    SANE_Device *sdev = (SANE_Device*) calloc(1, sizeof(SANE_Device));
    if (!sdev) {
       DBG (10, "Sane_Device allocation failure.\n");
       return NULL;
    }

    if (cdev->unix_socket && strlen(cdev->unix_socket)) {
        snprintf(unix_path, sizeof(unix_path), "unix:%s:", cdev->unix_socket);
    }
    len = snprintf(NULL, 0, "%shttp%s://%s:%d",
             unix_path, cdev->https ? "s" : "", cdev->ip_address, cdev->port_nb);
    len++;
    tmp = (char *)malloc(len);
    if (!tmp) {
        DBG (10, "Name allocation failure.\n");
        goto freedev;
    }
    snprintf(tmp, len, "%shttp%s://%s:%d",
             unix_path, cdev->https ? "s" : "", cdev->ip_address, cdev->port_nb);
    sdev->name = tmp;

    DBG( 1, "Escl add device : %s\n", tmp);
    sdev->vendor = get_vendor(cdev->model_name);

    if (!sdev->vendor)
       sdev->vendor = strdup("ESCL");
    else
       lv = strlen(sdev->vendor) + 1;
    if (!sdev->vendor) {
       DBG (10, "Vendor allocation failure.\n");
       goto freemodel;
    }
    sdev->model = strdup(lv + cdev->model_name);
    if (!sdev->model) {
       DBG (10, "Model allocation failure.\n");
       goto freename;
    }
    sdev->type = strdup("flatbed scanner");
    if (!sdev->type) {
       DBG (10, "Scanner Type allocation failure.\n");
       goto freevendor;
    }
    return (sdev);
freevendor:
    free((void*)sdev->vendor);
freemodel:
    free((void*)sdev->model);
freename:
    free((void*)sdev->name);
freedev:
    free((void*)sdev);
    return NULL;
}

/**
 * \fn SANE_Status sane_init(SANE_Int *version_code, SANE_Auth_Callback authorize)
 * \brief Function that's called before any other SANE function ; it's the first SANE function called.
 *        --> this function checks the SANE config. and can check the authentication of the user if
 *        'authorize' value is more than SANE_TRUE.
 *        In this case, it will be necessary to define an authentication method.
 *
 * \return SANE_STATUS_GOOD (everything is OK)
 */
SANE_Status
sane_init(SANE_Int *version_code, SANE_Auth_Callback __sane_unused__ authorize)
{
    DBG_INIT();
    DBG (10, "escl sane_init\n");
    SANE_Status status = SANE_STATUS_GOOD;
    curl_global_init(CURL_GLOBAL_ALL);
    if (version_code != NULL)
	*version_code = SANE_VERSION_CODE(1, 0, 0);
    if (status != SANE_STATUS_GOOD)
	return (status);
    return (SANE_STATUS_GOOD);
}

/**
 * \fn void sane_exit(void)
 * \brief Function that must be called to terminate use of a backend.
 *        This function will first close all device handles that still might be open.
 *        --> by freeing all the elements of my list.
 *        After this function, no function other than 'sane_init' may be called.
 */
void
sane_exit(void)
{
    DBG (10, "escl sane_exit\n");
    ESCL_Device *next = NULL;

    while (list_devices_primary != NULL) {
	next = list_devices_primary->next;
	free(list_devices_primary);
	list_devices_primary = next;
    }
    if (devlist)
	free (devlist);
    list_devices_primary = NULL;
    devlist = NULL;
    curl_global_cleanup();
}

/**
 * \fn static SANE_Status attach_one_config(SANEI_Config *config, const char *line)
 * \brief Function that implements a configuration file to the user :
 *        if the user can't detect some devices, he will be able to force their detection with this config' file to use them.
 *        Thus, this function parses the config' file to use the device of the user with the information below :
 *        the type of protocol (http/https), the ip, the port number, and the model name.
 *
 * \return escl_add_in_list(escl_device) if the parsing worked, SANE_STATUS_GOOD otherwise.
 */
static SANE_Status
attach_one_config(SANEI_Config __sane_unused__ *config, const char *line)
{
    int port = 0;
    SANE_Status status;
    static ESCL_Device *escl_device = NULL;

    if (strncmp(line, "device", 6) == 0) {
        char *name_str = NULL;
        char *opt_model = NULL;

        line = sanei_config_get_string(line + 6, &name_str);
        DBG (10, "New Escl_Device URL [%s].\n", (name_str ? name_str : "VIDE"));
        if (!name_str || !*name_str) {
            DBG (1, "Escl_Device URL missing.\n");
            return SANE_STATUS_INVAL;
        }
        if (*line) {
            line = sanei_config_get_string(line, &opt_model);
            DBG (10, "New Escl_Device model [%s].\n", opt_model);
        }

        escl_free_device(escl_device);
        escl_device = (ESCL_Device*)calloc(1, sizeof(ESCL_Device));
        if (!escl_device) {
           DBG (10, "New Escl_Device allocation failure.\n");
           free(name_str);
           return (SANE_STATUS_NO_MEM);
        }
        status = escl_parse_name(name_str, escl_device);
        free(name_str);
        if (status != SANE_STATUS_GOOD) {
            escl_free_device(escl_device);
            escl_device = NULL;
            return status;
        }
        escl_device->model_name = opt_model ? opt_model : strdup("Unknown model");
        escl_device->type = strdup("flatbed scanner");
    }

    if (strncmp(line, "[device]", 8) == 0) {
	escl_device = escl_free_device(escl_device);
	escl_device = (ESCL_Device*)calloc(1, sizeof(ESCL_Device));
	if (!escl_device) {
	   DBG (10, "New Escl_Device allocation failure.");
	   return (SANE_STATUS_NO_MEM);
	}
    }
    if (strncmp(line, "ip", 2) == 0) {
	const char *ip_space = sanei_config_skip_whitespace(line + 2);
	DBG (10, "New Escl_Device IP [%s].", (ip_space ? ip_space : "VIDE"));
	if (escl_device != NULL && ip_space != NULL) {
	    DBG (10, "New Escl_Device IP Affected.");
	    escl_device->ip_address = strdup(ip_space);
	}
    }
    if (sscanf(line, "port %i", &port) == 1 && port != 0) {
	DBG (10, "New Escl_Device PORT [%d].", port);
	if (escl_device != NULL) {
	    DBG (10, "New Escl_Device PORT Affected.");
	    escl_device->port_nb = port;
	}
    }
    if (strncmp(line, "model", 5) == 0) {
	const char *model_space = sanei_config_skip_whitespace(line + 5);
	DBG (10, "New Escl_Device MODEL [%s].", (model_space ? model_space : "VIDE"));
	if (escl_device != NULL && model_space != NULL) {
	    DBG (10, "New Escl_Device MODEL Affected.");
	    escl_device->model_name = strdup(model_space);
	}
    }
    if (strncmp(line, "type", 4) == 0) {
	const char *type_space = sanei_config_skip_whitespace(line + 4);
	DBG (10, "New Escl_Device TYPE [%s].", (type_space ? type_space : "VIDE"));
	if (escl_device != NULL && type_space != NULL) {
	    DBG (10, "New Escl_Device TYPE Affected.");
	    escl_device->type = strdup(type_space);
	}
    }
    status = escl_check_and_add_device(escl_device);
    if (status == SANE_STATUS_GOOD)
       escl_device = NULL;
    return status;
}

/**
 * \fn SANE_Status sane_get_devices(const SANE_Device ***device_list, SANE_Bool local_only)
 * \brief Function that searches for connected devices and places them in our 'device_list'. ('for' loop)
 *        If the attribute 'local_only' is worth SANE_FALSE, we only returns the connected devices locally.
 *
 * \return SANE_STATUS_GOOD if devlist != NULL ; SANE_STATUS_NO_MEM otherwise.
 */
SANE_Status
sane_get_devices(const SANE_Device ***device_list, SANE_Bool local_only)
{
    if (local_only)             /* eSCL is a network-only protocol */
	return (device_list ? SANE_STATUS_GOOD : SANE_STATUS_INVAL);

    DBG (10, "escl sane_get_devices\n");
    ESCL_Device *dev = NULL;
    static const SANE_Device **devlist = 0;
    SANE_Status status;

    if (device_list == NULL)
	return (SANE_STATUS_INVAL);
    status = sanei_configure_attach(ESCL_CONFIG_FILE, NULL, attach_one_config);
    if (status != SANE_STATUS_GOOD)
	return (status);
    escl_devices(&status);
    if (status != SANE_STATUS_GOOD)
	return (status);
    if (devlist)
	free(devlist);
    devlist = (const SANE_Device **) calloc (num_devices + 1, sizeof (devlist[0]));
    if (devlist == NULL)
	return (SANE_STATUS_NO_MEM);
    int i = 0;
    for (dev = list_devices_primary; i < num_devices; dev = dev->next) {
	SANE_Device *s_dev = convertFromESCLDev(dev);
	devlist[i] = s_dev;
	i++;
    }
    devlist[i] = 0;
    *device_list = devlist;
    return (devlist) ? SANE_STATUS_GOOD : SANE_STATUS_NO_MEM;
}

/* Returns the length of the longest string, including the terminating
 * character. */
static size_t
_source_size_max (SANE_String_Const * sources)
{
  size_t size = 0;

  while(*sources)
   {
      size_t t = strlen (*sources) + 1;
      if (t > size)
          size = t;
      sources++;
   }
  return size;
}

/**
 * \fn static SANE_Status init_options(SANE_String_Const name, escl_sane_t *s)
 * \brief Function thzt initializes all the needed options of the received scanner
 *        (the resolution / the color / the margins) thanks to the informations received with
 *        the 'escl_capabilities' function, called just before.
 *
 * \return status (if everything is OK, status = SANE_STATUS_GOOD)
 */
static SANE_Status
init_options(SANE_String_Const name_source, escl_sane_t *s)
{
    DBG (10, "escl init_options\n");

    SANE_Status status = SANE_STATUS_GOOD;
    int i = 0;
    if (!s->scanner) return SANE_STATUS_INVAL;
    if (name_source) {
	   int source = s->scanner->source;
	   DBG (10, "escl init_options name [%s]\n", name_source);
	   if (!strcmp(name_source, SANE_I18N ("ADF Duplex")))
	       s->scanner->source = ADFDUPLEX;
	   else if (!strncmp(name_source, "A", 1) ||
	            !strcmp(name_source, SANE_I18N ("ADF")))
	       s->scanner->source = ADFSIMPLEX;
	   else
	       s->scanner->source = PLATEN;
	   if (source == s->scanner->source) return status;
    }
    else
	   s->scanner->source = PLATEN;
    memset (s->opt, 0, sizeof (s->opt));
    memset (s->val, 0, sizeof (s->val));
    for (i = 0; i < NUM_OPTIONS; ++i) {
	   s->opt[i].size = sizeof (SANE_Word);
	   s->opt[i].cap = SANE_CAP_SOFT_SELECT | SANE_CAP_SOFT_DETECT;
    }
    s->x_range1.min = 0;
    s->x_range1.max =
	    PIXEL_TO_MM((s->scanner->caps[s->scanner->source].MaxWidth -
		         s->scanner->caps[s->scanner->source].MinWidth),
			300.0);
    s->x_range1.quant = 0;
    s->x_range2.min = PIXEL_TO_MM(s->scanner->caps[s->scanner->source].MinWidth, 300.0);
    s->x_range2.max = PIXEL_TO_MM(s->scanner->caps[s->scanner->source].MaxWidth, 300.0);
    s->x_range2.quant = 0;
    s->y_range1.min = 0;
    s->y_range1.max =
	    PIXEL_TO_MM((s->scanner->caps[s->scanner->source].MaxHeight -
	                 s->scanner->caps[s->scanner->source].MinHeight),
			300.0);
    s->y_range1.quant = 0;
    s->y_range2.min = PIXEL_TO_MM(s->scanner->caps[s->scanner->source].MinHeight, 300.0);
    s->y_range2.max = PIXEL_TO_MM(s->scanner->caps[s->scanner->source].MaxHeight, 300.0);
    s->y_range2.quant = 0;
    s->opt[OPT_NUM_OPTS].title = SANE_TITLE_NUM_OPTIONS;
    s->opt[OPT_NUM_OPTS].desc = SANE_DESC_NUM_OPTIONS;
    s->opt[OPT_NUM_OPTS].type = SANE_TYPE_INT;
    s->opt[OPT_NUM_OPTS].cap = SANE_CAP_SOFT_DETECT;
    s->val[OPT_NUM_OPTS].w = NUM_OPTIONS;

    s->opt[OPT_MODE_GROUP].title = SANE_TITLE_SCAN_MODE;
    s->opt[OPT_MODE_GROUP].desc = "";
    s->opt[OPT_MODE_GROUP].type = SANE_TYPE_GROUP;
    s->opt[OPT_MODE_GROUP].cap = 0;
    s->opt[OPT_MODE_GROUP].constraint_type = SANE_CONSTRAINT_NONE;

    s->opt[OPT_MODE].name = SANE_NAME_SCAN_MODE;
    s->opt[OPT_MODE].title = SANE_TITLE_SCAN_MODE;
    s->opt[OPT_MODE].desc = SANE_DESC_SCAN_MODE;
    s->opt[OPT_MODE].type = SANE_TYPE_STRING;
    s->opt[OPT_MODE].unit = SANE_UNIT_NONE;
    s->opt[OPT_MODE].constraint_type = SANE_CONSTRAINT_STRING_LIST;
    s->opt[OPT_MODE].constraint.string_list = s->scanner->caps[s->scanner->source].ColorModes;
    s->val[OPT_MODE].s = (char *)strdup(s->scanner->caps[s->scanner->source].ColorModes[0]);
    if (!s->val[OPT_MODE].s) {
       DBG (10, "Color Mode Default allocation failure.\n");
       return (SANE_STATUS_NO_MEM);
    }
    s->opt[OPT_MODE].size = max_string_size(s->scanner->caps[s->scanner->source].ColorModes);
    s->scanner->caps[s->scanner->source].default_color = (char *)strdup(s->scanner->caps[s->scanner->source].ColorModes[0]);
    if (!s->scanner->caps[s->scanner->source].default_color) {
       DBG (10, "Color Mode Default allocation failure.\n");
       return (SANE_STATUS_NO_MEM);
    }

    s->opt[OPT_RESOLUTION].name = SANE_NAME_SCAN_RESOLUTION;
    s->opt[OPT_RESOLUTION].title = SANE_TITLE_SCAN_RESOLUTION;
    s->opt[OPT_RESOLUTION].desc = SANE_DESC_SCAN_RESOLUTION;
    s->opt[OPT_RESOLUTION].type = SANE_TYPE_INT;
    s->opt[OPT_RESOLUTION].unit = SANE_UNIT_DPI;
    s->opt[OPT_RESOLUTION].constraint_type = SANE_CONSTRAINT_WORD_LIST;
    s->opt[OPT_RESOLUTION].constraint.word_list = s->scanner->caps[s->scanner->source].SupportedResolutions;
    s->val[OPT_RESOLUTION].w = s->scanner->caps[s->scanner->source].SupportedResolutions[1];
    s->scanner->caps[s->scanner->source].default_resolution = s->scanner->caps[s->scanner->source].SupportedResolutions[1];

    s->opt[OPT_PREVIEW].name = SANE_NAME_PREVIEW;
    s->opt[OPT_PREVIEW].title = SANE_TITLE_PREVIEW;
    s->opt[OPT_PREVIEW].desc = SANE_DESC_PREVIEW;
    s->opt[OPT_PREVIEW].cap = SANE_CAP_SOFT_DETECT | SANE_CAP_SOFT_SELECT;
    s->opt[OPT_PREVIEW].type = SANE_TYPE_BOOL;
    s->val[OPT_PREVIEW].w = SANE_FALSE;

    s->opt[OPT_GRAY_PREVIEW].name = SANE_NAME_GRAY_PREVIEW;
    s->opt[OPT_GRAY_PREVIEW].title = SANE_TITLE_GRAY_PREVIEW;
    s->opt[OPT_GRAY_PREVIEW].desc = SANE_DESC_GRAY_PREVIEW;
    s->opt[OPT_GRAY_PREVIEW].type = SANE_TYPE_BOOL;
    s->val[OPT_GRAY_PREVIEW].w = SANE_FALSE;

    s->opt[OPT_GEOMETRY_GROUP].title = SANE_TITLE_GEOMETRY;
    s->opt[OPT_GEOMETRY_GROUP].desc = SANE_DESC_GEOMETRY;
    s->opt[OPT_GEOMETRY_GROUP].type = SANE_TYPE_GROUP;
    s->opt[OPT_GEOMETRY_GROUP].cap = SANE_CAP_ADVANCED;
    s->opt[OPT_GEOMETRY_GROUP].constraint_type = SANE_CONSTRAINT_NONE;

    s->opt[OPT_TL_X].name = SANE_NAME_SCAN_TL_X;
    s->opt[OPT_TL_X].title = SANE_TITLE_SCAN_TL_X;
    s->opt[OPT_TL_X].desc = SANE_DESC_SCAN_TL_X;
    s->opt[OPT_TL_X].type = SANE_TYPE_FIXED;
    s->opt[OPT_TL_X].size = sizeof(SANE_Fixed);
    s->opt[OPT_TL_X].cap = SANE_CAP_SOFT_SELECT | SANE_CAP_SOFT_DETECT;
    s->opt[OPT_TL_X].unit = SANE_UNIT_MM;
    s->opt[OPT_TL_X].constraint_type = SANE_CONSTRAINT_RANGE;
    s->opt[OPT_TL_X].constraint.range = &s->x_range1;
    s->val[OPT_TL_X].w = s->x_range1.min;

    s->opt[OPT_TL_Y].name = SANE_NAME_SCAN_TL_Y;
    s->opt[OPT_TL_Y].title = SANE_TITLE_SCAN_TL_Y;
    s->opt[OPT_TL_Y].desc = SANE_DESC_SCAN_TL_Y;
    s->opt[OPT_TL_Y].type = SANE_TYPE_FIXED;
    s->opt[OPT_TL_Y].size = sizeof(SANE_Fixed);
    s->opt[OPT_TL_Y].cap = SANE_CAP_SOFT_SELECT | SANE_CAP_SOFT_DETECT;
    s->opt[OPT_TL_Y].unit = SANE_UNIT_MM;
    s->opt[OPT_TL_Y].constraint_type = SANE_CONSTRAINT_RANGE;
    s->opt[OPT_TL_Y].constraint.range = &s->y_range1;
    s->val[OPT_TL_Y].w = s->y_range1.min;

    s->opt[OPT_BR_X].name = SANE_NAME_SCAN_BR_X;
    s->opt[OPT_BR_X].title = SANE_TITLE_SCAN_BR_X;
    s->opt[OPT_BR_X].desc = SANE_DESC_SCAN_BR_X;
    s->opt[OPT_BR_X].type = SANE_TYPE_FIXED;
    s->opt[OPT_BR_X].size = sizeof(SANE_Fixed);
    s->opt[OPT_BR_X].cap = SANE_CAP_SOFT_SELECT | SANE_CAP_SOFT_DETECT;
    s->opt[OPT_BR_X].unit = SANE_UNIT_MM;
    s->opt[OPT_BR_X].constraint_type = SANE_CONSTRAINT_RANGE;
    s->opt[OPT_BR_X].constraint.range = &s->x_range2;
    s->val[OPT_BR_X].w = s->x_range2.max;

    s->opt[OPT_BR_Y].name = SANE_NAME_SCAN_BR_Y;
    s->opt[OPT_BR_Y].title = SANE_TITLE_SCAN_BR_Y;
    s->opt[OPT_BR_Y].desc = SANE_DESC_SCAN_BR_Y;
    s->opt[OPT_BR_Y].type = SANE_TYPE_FIXED;
    s->opt[OPT_BR_Y].size = sizeof(SANE_Fixed);
    s->opt[OPT_BR_Y].cap = SANE_CAP_SOFT_SELECT | SANE_CAP_SOFT_DETECT;
    s->opt[OPT_BR_Y].unit = SANE_UNIT_MM;
    s->opt[OPT_BR_Y].constraint_type = SANE_CONSTRAINT_RANGE;
    s->opt[OPT_BR_Y].constraint.range = &s->y_range2;
    s->val[OPT_BR_Y].w = s->y_range2.max;

	/* OPT_SCAN_SOURCE */
    s->opt[OPT_SCAN_SOURCE].name = SANE_NAME_SCAN_SOURCE;
    s->opt[OPT_SCAN_SOURCE].title = SANE_TITLE_SCAN_SOURCE;
    s->opt[OPT_SCAN_SOURCE].desc = SANE_DESC_SCAN_SOURCE;
    s->opt[OPT_SCAN_SOURCE].type = SANE_TYPE_STRING;
    s->opt[OPT_SCAN_SOURCE].size = _source_size_max(s->scanner->Sources);
    s->opt[OPT_SCAN_SOURCE].cap = SANE_CAP_SOFT_SELECT | SANE_CAP_SOFT_DETECT;
    s->opt[OPT_SCAN_SOURCE].constraint_type = SANE_CONSTRAINT_STRING_LIST;
    s->opt[OPT_SCAN_SOURCE].constraint.string_list = s->scanner->Sources;
    if (s->val[OPT_SCAN_SOURCE].s)
       free (s->val[OPT_SCAN_SOURCE].s);
    s->val[OPT_SCAN_SOURCE].s = strdup (s->scanner->Sources[s->scanner->source]);
    return (status);
}

SANE_Status
escl_parse_name(SANE_String_Const name, ESCL_Device *device)
{
    SANE_String_Const host = NULL;
    SANE_String_Const port_str = NULL;
    DBG(10, "escl_parse_name\n");
    if (name == NULL || device == NULL) {
        return SANE_STATUS_INVAL;
    }

    if (strncmp(name, "unix:", 5) == 0) {
        SANE_String_Const socket = name + 5;
        name = strchr(socket, ':');
        if (name == NULL)
            return SANE_STATUS_INVAL;
        device->unix_socket = strndup(socket, name - socket);
        name++;
    }

    if (strncmp(name, "https://", 8) == 0) {
        device->https = SANE_TRUE;
        host = name + 8;
    } else if (strncmp(name, "http://", 7) == 0) {
        device->https = SANE_FALSE;
        host = name + 7;
    } else {
        DBG(1, "Unknown URL scheme in %s", name);
        return SANE_STATUS_INVAL;
    }

    port_str = strchr(host, ':');
    if (port_str == NULL) {
        DBG(1, "Port missing from URL: %s", name);
        return SANE_STATUS_INVAL;
    }
    port_str++;
    device->port_nb = atoi(port_str);
    if (device->port_nb < 1 || device->port_nb > 65535) {
        DBG(1, "Invalid port number in URL: %s", name);
        return SANE_STATUS_INVAL;
    }

    device->ip_address = strndup(host, port_str - host - 1);
    return SANE_STATUS_GOOD;
}

/**
 * \fn SANE_Status sane_open(SANE_String_Const name, SANE_Handle *h)
 * \brief Function that establishes a connection with the device named by 'name',
 *        and returns a 'handler' using 'SANE_Handle *h', representing it.
 *        Thus, it's this function that calls the 'escl_status' function firstly,
 *        then the 'escl_capabilities' function, and, after, the 'init_options' function.
 *
 * \return status (if everything is OK, status = SANE_STATUS_GOOD, otherwise, SANE_STATUS_NO_MEM/SANE_STATUS_INVAL)
 */
SANE_Status
sane_open(SANE_String_Const name, SANE_Handle *h)
{
    DBG (10, "escl sane_open\n");
    SANE_Status status;
    escl_sane_t *handler = NULL;

    if (name == NULL)
        return (SANE_STATUS_INVAL);

    ESCL_Device *device = calloc(1, sizeof(ESCL_Device));
    if (device == NULL) {
        DBG (10, "Handle device allocation failure.\n");
        return SANE_STATUS_NO_MEM;
    }
    status = escl_parse_name(name, device);
    if (status != SANE_STATUS_GOOD) {
        escl_free_device(device);
        return status;
    }

    handler = (escl_sane_t *)calloc(1, sizeof(escl_sane_t));
    if (handler == NULL) {
        escl_free_device(device);
        return (SANE_STATUS_NO_MEM);
    }
    handler->device = device;  // Handler owns device now.
    handler->scanner = escl_capabilities(device, &status);
    if (status != SANE_STATUS_GOOD) {
        escl_free_handler(handler);
        return (status);
    }
    status = init_options(NULL, handler);
    if (status != SANE_STATUS_GOOD) {
        escl_free_handler(handler);
        return (status);
    }
    handler->ps.depth = 8;
    handler->ps.last_frame = SANE_TRUE;
    handler->ps.format = SANE_FRAME_RGB;
    handler->ps.pixels_per_line = MM_TO_PIXEL(handler->val[OPT_BR_X].w, 300.0);
    handler->ps.lines = MM_TO_PIXEL(handler->val[OPT_BR_Y].w, 300.0);
    handler->ps.bytes_per_line = handler->ps.pixels_per_line * 3;
    status = sane_get_parameters(handler, 0);
    if (status != SANE_STATUS_GOOD) {
        escl_free_handler(handler);
        return (status);
    }
    handler->cancel = SANE_FALSE;
    handler->write_scan_data = SANE_FALSE;
    handler->decompress_scan_data = SANE_FALSE;
    handler->end_read = SANE_FALSE;
    *h = handler;
    return (status);
}

/**
 * \fn void sane_cancel(SANE_Handle h)
 * \brief Function that's used to, immediately or as quickly as possible, cancel the currently
 *        pending operation of the device represented by 'SANE_Handle h'.
 *        This functions calls the 'escl_scanner' functions, that resets the scan operations.
 */
void
sane_cancel(SANE_Handle h)
{
    DBG (10, "escl sane_cancel\n");
    escl_sane_t *handler = h;
    if (handler->scanner->tmp)
    {
      fclose(handler->scanner->tmp);
      handler->scanner->tmp = NULL;
    }
    handler->scanner->work = SANE_FALSE;
    handler->cancel = SANE_TRUE;
    escl_scanner(handler->device, handler->result);
    free(handler->result);
    handler->result = NULL;
}

/**
 * \fn void sane_close(SANE_Handle h)
 * \brief Function that closes the communication with the device represented by 'SANE_Handle h'.
 *        This function must release the resources that were allocated to the opening of 'h'.
 */
void
sane_close(SANE_Handle h)
{
    DBG (10, "escl sane_close\n");
    if (h != NULL) {
        escl_free_handler(h);
        h = NULL;
    }
}

/**
 * \fn const SANE_Option_Descriptor *sane_get_option_descriptor(SANE_Handle h, SANE_Int n)
 * \brief Function that retrieves a descriptor from the n number option of the scanner
 *        represented by 'h'.
 *        The descriptor remains valid until the machine is closed.
 *
 * \return s->opt + n
 */
const SANE_Option_Descriptor *
sane_get_option_descriptor(SANE_Handle h, SANE_Int n)
{
    DBG (10, "escl sane_get_option_descriptor\n");
    escl_sane_t *s = h;

    if ((unsigned) n >= NUM_OPTIONS || n < 0)
	return (0);
    return (&s->opt[n]);
}

/**
 * \fn SANE_Status sane_control_option(SANE_Handle h, SANE_Int n, SANE_Action a, void *v, SANE_Int *i)
 * \brief Function that defines the actions to perform for the 'n' option of the machine,
 *        represented by 'h', if the action is 'a'.
 *        There are 3 types of possible actions :
 *        --> SANE_ACTION_GET_VALUE: 'v' must be used to provide the value of the option.
 *        --> SANE_ACTION_SET_VALUE: The option must take the 'v' value.
 *        --> SANE_ACTION_SET_AUTO: The backend or machine must affect the option with an appropriate value.
 *        Moreover, the parameter 'i' is used to provide additional information about the state of
 *        'n' option if SANE_ACTION_SET_VALUE has been performed.
 *
 * \return SANE_STATUS_GOOD if everything is OK, otherwise, SANE_STATUS_NO_MEM/SANE_STATUS_INVAL
 */
SANE_Status
sane_control_option(SANE_Handle h, SANE_Int n, SANE_Action a, void *v, SANE_Int *i)
{
    DBG (10, "escl sane_control_option\n");
    escl_sane_t *handler = h;

    if (i)
	*i = 0;
    if (n >= NUM_OPTIONS || n < 0)
	return (SANE_STATUS_INVAL);
    if (a == SANE_ACTION_GET_VALUE) {
	switch (n) {
	case OPT_TL_X:
	case OPT_TL_Y:
	case OPT_BR_X:
	case OPT_BR_Y:
	case OPT_NUM_OPTS:
	case OPT_RESOLUTION:
	case OPT_PREVIEW:
	case OPT_GRAY_PREVIEW:
	    *(SANE_Word *) v = handler->val[n].w;
	    break;
	case OPT_SCAN_SOURCE:
	case OPT_MODE:
	    strcpy (v, handler->val[n].s);
	    break;
	case OPT_MODE_GROUP:
	default:
	    break;
	}
	return (SANE_STATUS_GOOD);
    }
    if (a == SANE_ACTION_SET_VALUE) {
	switch (n) {
	case OPT_TL_X:
	case OPT_TL_Y:
	case OPT_BR_X:
	case OPT_BR_Y:
	case OPT_NUM_OPTS:
	case OPT_RESOLUTION:
	case OPT_PREVIEW:
	case OPT_GRAY_PREVIEW:
	    handler->val[n].w = *(SANE_Word *) v;
	    if (i)
		*i |= SANE_INFO_RELOAD_PARAMS | SANE_INFO_RELOAD_OPTIONS | SANE_INFO_INEXACT;
	    break;
	case OPT_SCAN_SOURCE:
	    DBG(10, "SET OPT_SCAN_SOURCE(%s)\n", (SANE_String_Const)v);
	    init_options((SANE_String_Const)v, handler);
	    if (i)
		*i |= SANE_INFO_RELOAD_PARAMS | SANE_INFO_RELOAD_OPTIONS | SANE_INFO_INEXACT;
	    break;
	case OPT_MODE:
	    if (handler->val[n].s)
		free (handler->val[n].s);
	    handler->val[n].s = strdup (v);
	    if (!handler->val[n].s) {
	      DBG (10, "OPT_MODE allocation failure.\n");
	      return (SANE_STATUS_NO_MEM);
	    }
	    if (i)
		*i |= SANE_INFO_RELOAD_PARAMS | SANE_INFO_RELOAD_OPTIONS | SANE_INFO_INEXACT;
	    break;
	default:
	    break;
	}
    }
    return (SANE_STATUS_GOOD);
}

static SANE_Bool
_go_next_page(SANE_Status status,
              SANE_Status job)
{
   // Thank's Alexander Pevzner (pzz@apevzner.com)
   SANE_Status st = SANE_STATUS_NO_DOCS;
   switch (status) {
      case SANE_STATUS_GOOD:
      case SANE_STATUS_UNSUPPORTED:
      case SANE_STATUS_DEVICE_BUSY: {
         DBG(10, "eSCL : Test next page\n");
         if (job != SANE_STATUS_GOOD) {
            DBG(10, "eSCL : Go next page\n");
            st = SANE_STATUS_GOOD;
         }
         break;
      }
      default:
         DBG(10, "eSCL : No next page\n");
   }
   return st;
}

/**
 * \fn SANE_Status sane_start(SANE_Handle h)
 * \brief Function that initiates aquisition of an image from the device represented by handle 'h'.
 *        This function calls the "escl_newjob" function and the "escl_scan" function.
 *
 * \return status (if everything is OK, status = SANE_STATUS_GOOD, otherwise, SANE_STATUS_NO_MEM/SANE_STATUS_INVAL)
 */
SANE_Status
sane_start(SANE_Handle h)
{
    DBG (10, "escl sane_start\n");
    SANE_Status status = SANE_STATUS_GOOD;
    escl_sane_t *handler = h;
    int w = 0;
    int he = 0;
    int bps = 0;

    if (handler->device == NULL) {
        DBG(1, "Missing handler device.\n");
        return (SANE_STATUS_INVAL);
    }
    handler->cancel = SANE_FALSE;
    handler->write_scan_data = SANE_FALSE;
    handler->decompress_scan_data = SANE_FALSE;
    handler->end_read = SANE_FALSE;
    if (handler->scanner->work == SANE_FALSE) {
       SANE_Status st = escl_status(handler->device,
                                    handler->scanner->source,
                                    NULL,
                                    NULL);
       if (st != SANE_STATUS_GOOD)
          return st;
       if(handler->scanner->caps[handler->scanner->source].default_color)
          free(handler->scanner->caps[handler->scanner->source].default_color);
       if (handler->val[OPT_PREVIEW].w == SANE_TRUE)
       {
          int i = 0, val = 9999;;
          if (handler->val[OPT_GRAY_PREVIEW].w == SANE_TRUE ||
	      !strcasecmp(handler->val[OPT_MODE].s, SANE_VALUE_SCAN_MODE_GRAY))
	     handler->scanner->caps[handler->scanner->source].default_color =
	          strdup("Grayscale8");
          else
	     handler->scanner->caps[handler->scanner->source].default_color =
	          strdup("RGB24");
          if (!handler->scanner->caps[handler->scanner->source].default_color) {
	     DBG (10, "Default Color allocation failure.\n");
	     return (SANE_STATUS_NO_MEM);
	  }
          for (i = 1; i < handler->scanner->caps[handler->scanner->source].SupportedResolutionsSize; i++)
          {
	     if (val > handler->scanner->caps[handler->scanner->source].SupportedResolutions[i])
	         val = handler->scanner->caps[handler->scanner->source].SupportedResolutions[i];
          }
          handler->scanner->caps[handler->scanner->source].default_resolution = val;
       }
       else
       {
          handler->scanner->caps[handler->scanner->source].default_resolution =
	     handler->val[OPT_RESOLUTION].w;
          if (!strcasecmp(handler->val[OPT_MODE].s, SANE_VALUE_SCAN_MODE_GRAY))
	     handler->scanner->caps[handler->scanner->source].default_color = strdup("Grayscale8");
          else if (!strcasecmp(handler->val[OPT_MODE].s, SANE_VALUE_SCAN_MODE_LINEART))
	     handler->scanner->caps[handler->scanner->source].default_color =
	         strdup("BlackAndWhite1");
          else
	     handler->scanner->caps[handler->scanner->source].default_color =
	         strdup("RGB24");
       }
       handler->scanner->caps[handler->scanner->source].height =
            MM_TO_PIXEL(handler->val[OPT_BR_Y].w, 300.0);
       handler->scanner->caps[handler->scanner->source].width =
            MM_TO_PIXEL(handler->val[OPT_BR_X].w, 300.0);;
       if (handler->x_range1.min == handler->val[OPT_TL_X].w)
           handler->scanner->caps[handler->scanner->source].pos_x = 0;
       else
           handler->scanner->caps[handler->scanner->source].pos_x =
               MM_TO_PIXEL((handler->val[OPT_TL_X].w - handler->x_range1.min),
               300.0);
       if (handler->y_range1.min == handler->val[OPT_TL_X].w)
           handler->scanner->caps[handler->scanner->source].pos_y = 0;
       else
           handler->scanner->caps[handler->scanner->source].pos_y =
               MM_TO_PIXEL((handler->val[OPT_TL_Y].w - handler->y_range1.min),
               300.0);
       DBG(10, "Calculate Size Image [%dx%d|%dx%d]\n",
	        handler->scanner->caps[handler->scanner->source].pos_x,
	        handler->scanner->caps[handler->scanner->source].pos_y,
	        handler->scanner->caps[handler->scanner->source].width,
	        handler->scanner->caps[handler->scanner->source].height);
       if (!handler->scanner->caps[handler->scanner->source].default_color) {
          DBG (10, "Default Color allocation failure.\n");
          return (SANE_STATUS_NO_MEM);
       }
       handler->result = escl_newjob(handler->scanner, handler->device, &status);
       if (status != SANE_STATUS_GOOD)
          return (status);
    }
    else
    {
       SANE_Status job = SANE_STATUS_UNSUPPORTED;
       SANE_Status st = escl_status(handler->device,
                                       handler->scanner->source,
                                       handler->result,
                                       &job);
       DBG(10, "eSCL : command returned status %s\n", sane_strstatus(st));
       if (_go_next_page(st, job) != SANE_STATUS_GOOD)
       {
         handler->scanner->work = SANE_FALSE;
         return SANE_STATUS_NO_DOCS;
       }
    }
    status = escl_scan(handler->scanner, handler->device, handler->result);
    if (status != SANE_STATUS_GOOD)
       return (status);
    if (!strcmp(handler->scanner->caps[handler->scanner->source].default_format, "image/jpeg"))
    {
       status = get_JPEG_data(handler->scanner, &w, &he, &bps);
    }
    else if (!strcmp(handler->scanner->caps[handler->scanner->source].default_format, "image/png"))
    {
       status = get_PNG_data(handler->scanner, &w, &he, &bps);
    }
    else if (!strcmp(handler->scanner->caps[handler->scanner->source].default_format, "image/tiff"))
    {
       status = get_TIFF_data(handler->scanner, &w, &he, &bps);
    }
    else if (!strcmp(handler->scanner->caps[handler->scanner->source].default_format, "application/pdf"))
    {
       status = get_PDF_data(handler->scanner, &w, &he, &bps);
    }
    else {
       DBG(10, "Unknow image format\n");
       return SANE_STATUS_INVAL;
    }

    DBG(10, "2-Size Image (%ld)[%dx%d|%dx%d]\n", handler->scanner->img_size, 0, 0, w, he);

    if (status != SANE_STATUS_GOOD)
       return (status);
    handler->ps.depth = 8;
    handler->ps.pixels_per_line = w;
    handler->ps.lines = he;
    handler->ps.bytes_per_line = w * bps;
    handler->ps.last_frame = SANE_TRUE;
    handler->ps.format = SANE_FRAME_RGB;
    handler->scanner->work = SANE_FALSE;
//    DBG(10, "NEXT Frame [%s]\n", (handler->ps.last_frame ? "Non" : "Oui"));
    DBG(10, "Real Size Image [%dx%d|%dx%d]\n", 0, 0, w, he);
    return (status);
}

/**
 * \fn SANE_Status sane_get_parameters(SANE_Handle h, SANE_Parameters *p)
 * \brief Function that retrieves the device parameters represented by 'h' and stores them in 'p'.
 *        This function is normally used after "sane_start".
 *        It's in this function that we choose to assign the default color. (Color or Monochrome)
 *
 * \return status (if everything is OK, status = SANE_STATUS_GOOD, otherwise, SANE_STATUS_NO_MEM/SANE_STATUS_INVAL)
 */
SANE_Status
sane_get_parameters(SANE_Handle h, SANE_Parameters *p)
{
    DBG (10, "escl sane_get_parameters\n");
    SANE_Status status = SANE_STATUS_GOOD;
    escl_sane_t *handler = h;

    if (status != SANE_STATUS_GOOD)
        return (status);
    if (p != NULL) {
        p->depth = 8;
        p->last_frame = handler->ps.last_frame;
        p->format = SANE_FRAME_RGB;
        p->pixels_per_line = handler->ps.pixels_per_line;
        p->lines = handler->ps.lines;
        p->bytes_per_line = handler->ps.bytes_per_line;
    }
    return (status);
}


/**
 * \fn SANE_Status sane_read(SANE_Handle h, SANE_Byte *buf, SANE_Int maxlen, SANE_Int *len)
 * \brief Function that's used to read image data from the device represented by handle 'h'.
 *        The argument 'buf' is a pointer to a memory area that is at least 'maxlen' bytes long.
 *        The number of bytes returned is stored in '*len'.
 *        --> When the call succeeds, the number of bytes returned can be anywhere in the range from 0 to 'maxlen' bytes.
 *
 * \return SANE_STATUS_GOOD (if everything is OK, otherwise, SANE_STATUS_NO_MEM/SANE_STATUS_INVAL)
 */
SANE_Status
sane_read(SANE_Handle h, SANE_Byte *buf, SANE_Int maxlen, SANE_Int *len)
{
    DBG (10, "escl sane_read\n");
    escl_sane_t *handler = h;
    SANE_Status status = SANE_STATUS_GOOD;
    long readbyte;

    if (!handler | !buf | !len)
        return (SANE_STATUS_INVAL);

    if (handler->cancel)
        return (SANE_STATUS_CANCELLED);
    if (!handler->write_scan_data)
        handler->write_scan_data = SANE_TRUE;
    if (!handler->decompress_scan_data) {
        if (status != SANE_STATUS_GOOD)
            return (status);
        handler->decompress_scan_data = SANE_TRUE;
    }
    if (handler->scanner->img_data == NULL)
        return (SANE_STATUS_INVAL);
    if (!handler->end_read) {
        readbyte = min((handler->scanner->img_size - handler->scanner->img_read), maxlen);
        memcpy(buf, handler->scanner->img_data + handler->scanner->img_read, readbyte);
        handler->scanner->img_read = handler->scanner->img_read + readbyte;
        *len = readbyte;
        if (handler->scanner->img_read == handler->scanner->img_size)
            handler->end_read = SANE_TRUE;
        else if (handler->scanner->img_read > handler->scanner->img_size) {
            *len = 0;
            handler->end_read = SANE_TRUE;
            free(handler->scanner->img_data);
            handler->scanner->img_data = NULL;
            return (SANE_STATUS_INVAL);
        }
    }
    else {
        SANE_Status job = SANE_STATUS_UNSUPPORTED;
        *len = 0;
        free(handler->scanner->img_data);
        handler->scanner->img_data = NULL;
        if (handler->scanner->source != PLATEN) {
	      SANE_Bool next_page = SANE_FALSE;
          SANE_Status st = escl_status(handler->device,
                                       handler->scanner->source,
                                       handler->result,
                                       &job);
          DBG(10, "eSCL : command returned status %s\n", sane_strstatus(st));
          if (_go_next_page(st, job) == SANE_STATUS_GOOD)
	     next_page = SANE_TRUE;
          handler->scanner->work = SANE_TRUE;
          handler->ps.last_frame = !next_page;
        }
        return SANE_STATUS_EOF;
    }
    return (SANE_STATUS_GOOD);
}

SANE_Status
sane_get_select_fd(SANE_Handle __sane_unused__ h, SANE_Int __sane_unused__ *fd)
{
    return (SANE_STATUS_UNSUPPORTED);
}

SANE_Status
sane_set_io_mode(SANE_Handle __sane_unused__ handle, SANE_Bool __sane_unused__ non_blocking)
{
    return (SANE_STATUS_UNSUPPORTED);
}

/**
 * \fn void escl_curl_url(CURL *handle, const ESCL_Device *device, SANE_String_Const path)
 * \brief Uses the device info in 'device' and the path from 'path' to construct
 *        a full URL.  Sets this URL and any necessary connection options into
 *        'handle'.
 */
void
escl_curl_url(CURL *handle, const ESCL_Device *device, SANE_String_Const path)
{
    int url_len;
    char *url;

    url_len = snprintf(NULL, 0, "%s://%s:%d%s",
                       (device->https ? "https" : "http"), device->ip_address,
                       device->port_nb, path);
    url_len++;
    url = (char *)malloc(url_len);
    snprintf(url, url_len, "%s://%s:%d%s",
             (device->https ? "https" : "http"), device->ip_address,
             device->port_nb, path);

    DBG( 1, "escl_curl_url: URL: %s\n", url );
    curl_easy_setopt(handle, CURLOPT_URL, url);
    free(url);
    if (device->https) {
        DBG( 1, "Ignoring safety certificates, use https\n");
        curl_easy_setopt(handle, CURLOPT_SSL_VERIFYPEER, 0L);
        curl_easy_setopt(handle, CURLOPT_SSL_VERIFYHOST, 0L);
    }
    if (device->unix_socket != NULL) {
        DBG( 1, "Using local socket %s\n", device->unix_socket );
        curl_easy_setopt(handle, CURLOPT_UNIX_SOCKET_PATH,
                         device->unix_socket);
    }
}