1 /* sane - Scanner Access Now Easy.
2
3 Copyright (C) 2019 Touboul Nathane
4 Copyright (C) 2019 Thierry HUCHARD <thierry@ordissimo.com>
5
6 This file is part of the SANE package.
7
8 SANE is free software; you can redistribute it and/or modify it under
9 the terms of the GNU General Public License as published by the Free
10 Software Foundation; either version 3 of the License, or (at your
11 option) any later version.
12
13 SANE is distributed in the hope that it will be useful, but WITHOUT
14 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
15 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
16 for more details.
17
18 You should have received a copy of the GNU General Public License
19 along with sane; see the file COPYING.
20 If not, see <https://www.gnu.org/licenses/>.
21
22 This file implements a SANE backend for eSCL scanners. */
23
24 #define DEBUG_DECLARE_ONLY
25 #include "../include/sane/config.h"
26
27 #include "escl.h"
28
29 #include <stdio.h>
30 #include <stdlib.h>
31 #include <string.h>
32
33 #include "../include/sane/sanei.h"
34
35 /**
36 * \fn static size_t write_callback(void *str, size_t size, size_t nmemb, void *userp)
37 * \brief Callback function that writes the image scanned into the temporary file.
38 *
39 * \return to_write (the result of the fwrite function)
40 */
41 static size_t
write_callback(void *str, size_t size, size_t nmemb, void *userp)42 write_callback(void *str, size_t size, size_t nmemb, void *userp)
43 {
44 capabilities_t *scanner = (capabilities_t *)userp;
45 size_t to_write = fwrite(str, size, nmemb, scanner->tmp);
46 scanner->real_read += to_write;
47 return (to_write);
48 }
49
50 /**
51 * \fn SANE_Status escl_scan(capabilities_t *scanner, const ESCL_Device *device, char *result)
52 * \brief Function that, after recovering the 'new job', scans the image writed in the
53 * temporary file, using curl.
54 * This function is called in the 'sane_start' function and it's the equivalent of
55 * the following curl command : "curl -s http(s)://'ip:'port'/eSCL/ScanJobs/'new job'/NextDocument > image.jpg".
56 *
57 * \return status (if everything is OK, status = SANE_STATUS_GOOD, otherwise, SANE_STATUS_NO_MEM/SANE_STATUS_INVAL)
58 */
59 SANE_Status
escl_scan(capabilities_t *scanner, const ESCL_Device *device, char *scanJob, char *result)60 escl_scan(capabilities_t *scanner, const ESCL_Device *device, char *scanJob, char *result)
61 {
62 CURL *curl_handle = NULL;
63 const char *scan_jobs = "/eSCL/";
64 const char *scanner_start = "/NextDocument";
65 char scan_cmd[PATH_MAX] = { 0 };
66 SANE_Status status = SANE_STATUS_GOOD;
67
68 if (device == NULL)
69 return (SANE_STATUS_NO_MEM);
70 scanner->real_read = 0;
71 curl_handle = curl_easy_init();
72 if (curl_handle != NULL) {
73 snprintf(scan_cmd, sizeof(scan_cmd), "%s%s%s%s",
74 scan_jobs, scanJob, result, scanner_start);
75 escl_curl_url(curl_handle, device, scan_cmd);
76 curl_easy_setopt(curl_handle, CURLOPT_WRITEFUNCTION, write_callback);
77 curl_easy_setopt(curl_handle, CURLOPT_FOLLOWLOCATION, 1L);
78 curl_easy_setopt(curl_handle, CURLOPT_MAXREDIRS, 3L);
79 if (scanner->tmp)
80 fclose(scanner->tmp);
81 scanner->tmp = tmpfile();
82 if (scanner->tmp != NULL) {
83 curl_easy_setopt(curl_handle, CURLOPT_WRITEDATA, scanner);
84 CURLcode res = curl_easy_perform(curl_handle);
85 if (res != CURLE_OK) {
86 DBG( 1, "Unable to scan: %s\n", curl_easy_strerror(res));
87 scanner->real_read = 0;
88 fclose(scanner->tmp);
89 scanner->tmp = NULL;
90 status = SANE_STATUS_INVAL;
91 goto cleanup;
92 }
93 fseek(scanner->tmp, 0, SEEK_SET);
94 }
95 else
96 status = SANE_STATUS_NO_MEM;
97 cleanup:
98 curl_easy_cleanup(curl_handle);
99 }
100 DBG(10, "eSCL scan : [%s]\treal read (%ld)\n", sane_strstatus(status), scanner->real_read);
101 if (scanner->real_read == 0)
102 {
103 fclose(scanner->tmp);
104 scanner->tmp = NULL;
105 return SANE_STATUS_NO_DOCS;
106 }
107 return (status);
108 }
109