Merge branch 'release/experimental/1.0.29-1_experimental1'experimental/1.0.29-1_experimental1

11 files changed, 2643 insertions, 0 deletions

diff --git a/backend/escl/escl.c b/backend/escl/escl.c
new file mode 100644
index 0000000..8df6c5c
--- /dev/null
+++ b/backend/escl/escl.c
@@ -0,0 +1,777 @@
+/* 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;
+    SANE_String_Const name;
+    char *result;
+    ESCL_ScanParam param;
+    SANE_Option_Descriptor opt[NUM_OPTIONS];
+    Option_Value val[NUM_OPTIONS];
+    capabilities_t *scanner;
+    SANE_Range x_range;
+    SANE_Range y_range;
+    SANE_Bool cancel;
+    SANE_Bool write_scan_data;
+    SANE_Bool decompress_scan_data;
+    SANE_Bool end_read;
+    SANE_Parameters ps;
+} escl_sane_t;
+
+/**
+ * \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)
+{
+    ++num_devices;
+    current->next = list_devices_primary;
+    list_devices_primary = current;
+    return (SANE_STATUS_GOOD);
+}
+
+/**
+ * \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)
+{
+    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 && current->port_nb == port_nb
+            && strcmp(current->type, type) == 0)
+            return (SANE_STATUS_GOOD);
+    }
+    current = malloc(sizeof(*current));
+    if (current == NULL)
+        return (SANE_STATUS_NO_MEM);
+    memset(current, 0, sizeof(*current));
+    current->port_nb = port_nb;
+    current->model_name = strdup(model_name);
+    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);
+}
+
+/**
+ * \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)
+{
+    SANE_Device *sdev = (SANE_Device*) calloc(1, sizeof(SANE_Device));
+    char tmp[PATH_MAX] = { 0 };
+
+    if (strcmp(cdev->type, "_uscan._tcp") == 0 || strcmp(cdev->type, "http") == 0)
+        snprintf(tmp, sizeof(tmp), "http://%s:%d", cdev->ip_address, cdev->port_nb);
+    else
+        snprintf(tmp, sizeof(tmp), "https://%s:%d", cdev->ip_address, cdev->port_nb);
+    DBG( 1, "Escl add device : %s\n", tmp);
+    sdev->name = strdup(tmp);
+    sdev->model = strdup(cdev->model_name);
+    sdev->vendor = strdup("ESCL");
+    sdev->type = strdup("flatbed scanner");
+    return (sdev);
+}
+
+/**
+ * \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;
+    static int count = 0;
+    static ESCL_Device *escl_device = NULL;
+
+    if (strncmp(line, "[device]", 8) == 0) {
+        count = 0;
+        escl_device = (ESCL_Device*)calloc(1, sizeof(ESCL_Device));
+    }
+    if (strncmp(line, "ip", 2) == 0) {
+        const char *ip_space = sanei_config_skip_whitespace(line + 2);
+        if (escl_device != NULL && ip_space != NULL) {
+            count++;
+            escl_device->ip_address = strdup(ip_space);
+        }
+    }
+    if (sscanf(line, "port %i", &port) == 1 && port != 0) {
+        const char *port_space = sanei_config_skip_whitespace(line + 4);
+        if (escl_device != NULL && port_space != NULL) {
+            count++;
+            escl_device->port_nb = port;
+        }
+    }
+    if (strncmp(line, "model", 5) == 0) {
+        const char *model_space = sanei_config_skip_whitespace(line + 5);
+        if (escl_device != NULL && model_space != NULL) {
+            count++;
+            escl_device->model_name = strdup(model_space);
+        }
+    }
+    if (strncmp(line, "type", 4) == 0) {
+        const char *type_space = sanei_config_skip_whitespace(line + 4);
+        if (escl_device != NULL && type_space != NULL) {
+            count++;
+            escl_device->type = strdup(type_space);
+        }
+    }
+    if (count == 4)
+        return (escl_add_in_list(escl_device));
+    return (SANE_STATUS_GOOD);
+}
+
+/**
+ * \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;
+}
+
+/**
+ * \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, escl_sane_t *s)
+{
+    DBG (10, "escl init_options\n");
+    SANE_Status status = SANE_STATUS_GOOD;
+    int i = 0;
+
+    if (name == NULL)
+        return (SANE_STATUS_INVAL);
+    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_range.min = 0;
+    s->x_range.max = s->scanner->MaxWidth - s->scanner->MinWidth;
+    s->x_range.quant = 1;
+    s->y_range.min = 0;
+    s->y_range.max = s->scanner->MaxHeight - s->scanner->MinHeight;
+    s->y_range.quant = 1;
+    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->ColorModes;
+    s->val[OPT_MODE].s = (char *)strdup(s->scanner->ColorModes[0]);
+    s->opt[OPT_MODE].size = max_string_size(s->scanner->ColorModes);
+    s->scanner->default_color = (char *)strdup(s->scanner->ColorModes[0]);
+
+    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->SupportedResolutions;
+    s->val[OPT_RESOLUTION].w = s->scanner->SupportedResolutions[1];
+    s->scanner->default_resolution = s->scanner->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 = "";
+    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].unit = SANE_UNIT_PIXEL;
+    s->opt[OPT_TL_X].constraint_type = SANE_CONSTRAINT_RANGE;
+    s->opt[OPT_TL_X].constraint.range = &s->x_range;
+    s->val[OPT_TL_X].w = s->scanner->RiskyLeftMargin;
+
+    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].unit = SANE_UNIT_PIXEL;
+    s->opt[OPT_TL_Y].constraint_type = SANE_CONSTRAINT_RANGE;
+    s->opt[OPT_TL_Y].constraint.range = &s->y_range;
+    s->val[OPT_TL_Y].w = s->scanner->RiskyTopMargin;
+
+    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].unit = SANE_UNIT_PIXEL;
+    s->opt[OPT_BR_X].constraint_type = SANE_CONSTRAINT_RANGE;
+    s->opt[OPT_BR_X].constraint.range = &s->x_range;
+    s->val[OPT_BR_X].w = s->scanner->MaxWidth;
+
+    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].unit = SANE_UNIT_PIXEL;
+    s->opt[OPT_BR_Y].constraint_type = SANE_CONSTRAINT_RANGE;
+    s->opt[OPT_BR_Y].constraint.range = &s->y_range;
+    s->val[OPT_BR_Y].w = s->scanner->MaxHeight;
+    return (status);
+}
+
+/**
+ * \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);
+    status = escl_status(name);
+    if (status != SANE_STATUS_GOOD)
+        return (status);
+    handler = (escl_sane_t *)calloc(1, sizeof(escl_sane_t));
+    if (handler == NULL)
+        return (SANE_STATUS_NO_MEM);
+    handler->name = strdup(name);
+    handler->scanner = escl_capabilities(name, &status);
+    if (status != SANE_STATUS_GOOD)
+        return (status);
+    status = init_options(name, handler);
+    if (status != SANE_STATUS_GOOD)
+        return (status);
+    handler->ps.depth = 8;
+    handler->ps.last_frame = SANE_TRUE;
+    handler->ps.format = SANE_FRAME_RGB;
+    handler->ps.pixels_per_line = handler->val[OPT_BR_X].w;
+    handler->ps.lines = handler->val[OPT_BR_Y].w;
+    handler->ps.bytes_per_line = handler->ps.pixels_per_line * 3;
+    status = sane_get_parameters(handler, 0);
+    if (status != SANE_STATUS_GOOD)
+        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->cancel = SANE_TRUE;
+    escl_scanner(handler->name, handler->result);
+}
+
+/**
+ * \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) {
+        free(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_NUM_OPTS:
+        case OPT_RESOLUTION:
+        case OPT_TL_X:
+        case OPT_TL_Y:
+        case OPT_BR_X:
+        case OPT_BR_Y:
+        case OPT_PREVIEW:
+        case OPT_GRAY_PREVIEW:
+            *(SANE_Word *) v = handler->val[n].w;
+            break;
+        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_PREVIEW:
+        case OPT_GRAY_PREVIEW:
+            handler->val[n].w = *(SANE_Word *) v;
+            if (i && handler->val[n].w != *(SANE_Word *) v)
+                *i |= SANE_INFO_RELOAD_PARAMS | SANE_INFO_RELOAD_OPTIONS | SANE_INFO_INEXACT;
+            handler->val[n].w = *(SANE_Word *) v;
+            break;
+        case OPT_RESOLUTION:
+            handler->val[n].w = *(SANE_Word *) v;
+            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 (i)
+                *i |= SANE_INFO_RELOAD_PARAMS | SANE_INFO_RELOAD_OPTIONS | SANE_INFO_INEXACT;
+            break;
+        default:
+            break;
+        }
+    }
+    return (SANE_STATUS_GOOD);
+}
+
+/**
+ * \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->name == NULL)
+        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;
+    handler->scanner->height = handler->val[OPT_BR_Y].w;
+    handler->scanner->width = handler->val[OPT_BR_X].w;
+    handler->scanner->pos_x = handler->val[OPT_TL_X].w;
+    handler->scanner->pos_y = handler->val[OPT_TL_Y].w;
+    if(handler->scanner->default_color)
+       free(handler->scanner->default_color);
+    if (handler->val[OPT_PREVIEW].w == SANE_TRUE)
+    {
+       int i = 0, val = 9999;;
+       if (handler->val[OPT_GRAY_PREVIEW].w == SANE_TRUE ||
+           !strncasecmp(handler->val[OPT_MODE].s, SANE_VALUE_SCAN_MODE_GRAY, 3))
+          handler->scanner->default_color = strdup("Grayscale8");
+       else
+          handler->scanner->default_color = strdup("RGB24");
+       for (i = 1; i < handler->scanner->SupportedResolutionsSize; i++)
+       {
+          if (val > handler->scanner->SupportedResolutions[i])
+              val = handler->scanner->SupportedResolutions[i];
+       }
+       handler->scanner->default_resolution = val;
+    }
+    else
+    {
+    handler->scanner->default_resolution = handler->val[OPT_RESOLUTION].w;
+    if (!strncasecmp(handler->val[OPT_MODE].s, SANE_VALUE_SCAN_MODE_GRAY, 3))
+       handler->scanner->default_color = strdup("Grayscale8");
+    else
+       handler->scanner->default_color = strdup("RGB24");
+    }
+    handler->result = escl_newjob(handler->scanner, handler->name, &status);
+    if (status != SANE_STATUS_GOOD)
+        return (status);
+    status = escl_scan(handler->scanner, handler->name, handler->result);
+    if (status != SANE_STATUS_GOOD)
+        return (status);
+    if (!strcmp(handler->scanner->default_format, "image/jpeg"))
+    {
+       status = get_JPEG_data(handler->scanner, &w, &he, &bps);
+    }
+    else if (!strcmp(handler->scanner->default_format, "image/png"))
+    {
+       status = get_PNG_data(handler->scanner, &w, &he, &bps);
+    }
+    else if (!strcmp(handler->scanner->default_format, "image/tiff"))
+    {
+       status = get_TIFF_data(handler->scanner, &w, &he, &bps);
+    }
+    else
+      return SANE_STATUS_INVAL;
+
+    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;
+    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 = SANE_TRUE;
+        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 {
+        *len = 0;
+        free(handler->scanner->img_data);
+        handler->scanner->img_data = NULL;
+        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);
+}
diff --git a/backend/escl/escl.h b/backend/escl/escl.h
new file mode 100644
index 0000000..82910bd
--- /dev/null
+++ b/backend/escl/escl.h
@@ -0,0 +1,171 @@
+/* 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.  */
+
+
+#ifndef __ESCL_H__
+#define __ESCL_H__
+
+#include "../include/sane/config.h"
+
+#if !(HAVE_LIBCURL && defined(WITH_AVAHI) && defined(HAVE_LIBXML2))
+#error "The escl backend requires libcurl, libavahi and libxml2"
+#endif
+
+#ifndef HAVE_LIBJPEG
+/* FIXME: Make JPEG support optional.
+   Support for PNG and PDF is to be added later but currently only
+   JPEG is supported.  Absence of JPEG support makes the backend a
+   no-op at present.
+ */
+#error "The escl backend currently requires libjpeg"
+#endif
+
+#include "../include/sane/sane.h"
+
+#include <stdio.h>
+
+#ifndef BACKEND_NAME
+#define BACKEND_NAME escl
+#endif
+
+#define DEBUG_NOT_STATIC
+#include "../include/sane/sanei_debug.h"
+
+#ifndef DBG_LEVEL
+#define DBG_LEVEL       PASTE(sanei_debug_, BACKEND_NAME)
+#endif
+#ifndef NDEBUG
+# define DBGDUMP(level, buf, size) \
+    do { if (DBG_LEVEL >= (level)) sanei_escl_dbgdump(buf, size); } while (0)
+#else
+# define DBGDUMP(level, buf, size)
+#endif
+
+#define ESCL_CONFIG_FILE "escl.conf"
+
+typedef struct {
+    int             p1_0;
+    int             p2_0;
+    int             p3_3;
+    int             DocumentType;
+    int             p4_0;
+    int             p5_0;
+    int             p6_1;
+    int             reserve[11];
+} ESCL_SCANOPTS;
+
+
+typedef struct ESCL_Device {
+    struct ESCL_Device *next;
+
+    char    *model_name;
+    int             port_nb;
+    char      *ip_address;
+    char *type;
+} ESCL_Device;
+
+typedef struct capabilities
+{
+    int height;
+    int width;
+    int pos_x;
+    int pos_y;
+    SANE_String default_color;
+    SANE_String default_format;
+    SANE_Int default_resolution;
+    int MinWidth;
+    int MaxWidth;
+    int MinHeight;
+    int MaxHeight;
+    int MaxScanRegions;
+    SANE_String_Const *ColorModes;
+    int ColorModesSize;
+    SANE_String_Const *ContentTypes;
+    int ContentTypesSize;
+    SANE_String_Const *DocumentFormats;
+    int DocumentFormatsSize;
+    SANE_Int *SupportedResolutions;
+    int SupportedResolutionsSize;
+    SANE_String_Const *SupportedIntents;
+    int SupportedIntentsSize;
+    SANE_String_Const SupportedIntentDefault;
+    int MaxOpticalXResolution;
+    int RiskyLeftMargin;
+    int RiskyRightMargin;
+    int RiskyTopMargin;
+    int RiskyBottomMargin;
+    FILE *tmp;
+    unsigned char *img_data;
+    long img_size;
+    long img_read;
+    int format_ext;
+} capabilities_t;
+
+typedef struct {
+    int                             XRes;
+    int                             YRes;
+    int                             Left;
+    int                             Top;
+    int                             Right;
+    int                             Bottom;
+    int                             ScanMode;
+    int                             ScanMethod;
+    ESCL_SCANOPTS  opts;
+} ESCL_ScanParam;
+
+
+enum
+{
+    OPT_NUM_OPTS = 0,
+    OPT_MODE_GROUP,
+    OPT_MODE,
+    OPT_RESOLUTION,
+    OPT_PREVIEW,
+    OPT_GRAY_PREVIEW,
+
+    OPT_GEOMETRY_GROUP,
+    OPT_TL_X,
+    OPT_TL_Y,
+    OPT_BR_X,
+    OPT_BR_Y,
+    NUM_OPTIONS
+};
+
+ESCL_Device *escl_devices(SANE_Status *status);
+SANE_Status escl_device_add(int port_nb, const char *model_name, char *ip_address, char *type);
+SANE_Status escl_status(SANE_String_Const name);
+capabilities_t *escl_capabilities(SANE_String_Const name, SANE_Status *status);
+char *escl_newjob(capabilities_t *scanner, SANE_String_Const name, SANE_Status *status);
+SANE_Status escl_scan(capabilities_t *scanner, SANE_String_Const name, char *result);
+void escl_scanner(SANE_String_Const name, char *result);
+
+// JPEG
+SANE_Status get_JPEG_data(capabilities_t *scanner, int *w, int *h, int *bps);
+
+// PNG
+SANE_Status get_PNG_data(capabilities_t *scanner, int *w, int *h, int *bps);
+
+// TIFF
+SANE_Status get_TIFF_data(capabilities_t *scanner, int *w, int *h, int *bps);
+
+#endif
diff --git a/backend/escl/escl_capabilities.c b/backend/escl/escl_capabilities.c
new file mode 100644
index 0000000..690ff1e
--- /dev/null
+++ b/backend/escl/escl_capabilities.c
@@ -0,0 +1,377 @@
+/* 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.  */
+
+#define DEBUG_DECLARE_ONLY
+#include "../include/sane/config.h"
+
+#include "escl.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <curl/curl.h>
+#include <libxml/parser.h>
+
+#include "../include/sane/saneopts.h"
+
+struct cap
+{
+    char *memory;
+    size_t size;
+};
+
+/**
+ * \fn static SANE_String_Const convert_elements(SANE_String_Const str)
+ * \brief Function that converts the 'color modes' of the scanner (color/gray) to be understood by SANE.
+ *
+ * \return SANE_VALUE_SCAN_MODE_GRAY / SANE_VALUE_SCAN_MODE_COLOR ; NULL otherwise
+ */
+static SANE_String_Const
+convert_elements(SANE_String_Const str)
+{
+    if (strcmp(str, "Grayscale8") == 0)
+        return (SANE_VALUE_SCAN_MODE_GRAY);
+    else if (strcmp(str, "RGB24") == 0)
+        return (SANE_VALUE_SCAN_MODE_COLOR);
+    return (NULL);
+}
+
+/**
+ * \fn static SANE_String_Const *char_to_array(SANE_String_Const *tab, int *tabsize, SANE_String_Const mode, int good_array)
+ * \brief Function that creates the character arrays to put inside :
+ *        the 'color modes', the 'content types', the 'document formats' and the 'supported intents'.
+ *
+ * \return board (the allocated array)
+ */
+static SANE_String_Const *
+char_to_array(SANE_String_Const *tab, int *tabsize, SANE_String_Const mode, int good_array)
+{
+    SANE_String_Const *board = NULL;
+    int i = 0;
+    SANE_String_Const convert = NULL;
+
+    if (mode == NULL)
+        return (tab);
+    if (good_array != 0) {
+        convert = convert_elements(mode);
+        if (convert == NULL)
+            return (tab);
+    }
+    else
+        convert = mode;
+    for (i = 0; i < (*tabsize); i++) {
+        if (strcmp(tab[i], convert) == 0)
+            return (tab);
+    }
+    (*tabsize)++;
+    if (*tabsize == 1)
+        board = (SANE_String_Const *)malloc(sizeof(SANE_String_Const) * (*tabsize) + 1);
+    else
+        board = (SANE_String_Const *)realloc(tab, sizeof(SANE_String_Const) * (*tabsize) + 1);
+    board[*tabsize - 1] = (SANE_String_Const)strdup(convert);
+    board[*tabsize] = NULL;
+    return (board);
+}
+
+/**
+ * \fn static SANE_Int *int_to_array(SANE_Int *tab, int *tabsize, int cont)
+ * \brief Function that creates the integer array to put inside the 'supported resolutions'.
+ *
+ * \return board (the allocated array)
+ */
+static SANE_Int *
+int_to_array(SANE_Int *tab, int *tabsize, int cont)
+{
+    SANE_Int *board = NULL;
+    int i = 0;
+
+    for (i = 0; i < (*tabsize); i++) {
+        if (tab[i] == cont)
+            return (tab);
+    }
+    (*tabsize)++;
+    if (*tabsize == 1) {
+        (*tabsize)++;
+        board = malloc(sizeof(SANE_Int *) * (*tabsize) + 1);
+    }
+    else
+        board = realloc(tab, sizeof(SANE_Int *) * (*tabsize) + 1);
+    board[0] = *tabsize - 1;
+    board[*tabsize - 1] = cont;
+    board[*tabsize] = -1;
+    return (board);
+}
+
+/**
+ * \fn static size_t memory_callback_c(void *contents, size_t size, size_t nmemb, void *userp)
+ * \brief Callback function that stocks in memory the content of the scanner capabilities.
+ *
+ * \return realsize (size of the content needed -> the scanner capabilities)
+ */
+static size_t
+memory_callback_c(void *contents, size_t size, size_t nmemb, void *userp)
+{
+    size_t realsize = size * nmemb;
+    struct cap *mem = (struct cap *)userp;
+
+    char *str = realloc(mem->memory, mem->size + realsize + 1);
+    if (str == NULL) {
+        fprintf(stderr, "not enough memory (realloc returned NULL)\n");
+        return (0);
+    }
+    mem->memory = str;
+    memcpy(&(mem->memory[mem->size]), contents, realsize);
+    mem->size = mem->size + realsize;
+    mem->memory[mem->size] = 0;
+    return (realsize);
+}
+
+/**
+ * \fn static int find_nodes_c(xmlNode *node)
+ * \brief Function that browses the xml file and parses it, to find the xml children node.
+ *        --> to recover the scanner capabilities.
+ *
+ * \return 0 if a xml child node is found, 1 otherwise
+ */
+static int
+find_nodes_c(xmlNode *node)
+{
+    xmlNode *child = node->children;
+
+    while (child) {
+        if (child->type == XML_ELEMENT_NODE)
+            return (0);
+        child = child->next;
+    }
+    return (1);
+}
+
+/**
+ * \fn static int find_valor_of_array_variables(xmlNode *node, capabilities_t *scanner)
+ * \brief Function that searchs in the xml file if a scanner capabilitie stocked
+ *        in one of the created array (character/integer array) is found.
+ *
+ * \return 0
+ */
+static int
+find_valor_of_array_variables(xmlNode *node, capabilities_t *scanner)
+{
+    const char *name = (const char *)node->name;
+    if (strcmp(name, "ColorMode") == 0)
+        scanner->ColorModes = char_to_array(scanner->ColorModes, &scanner->ColorModesSize, (SANE_String_Const)xmlNodeGetContent(node), 1);
+    else if (strcmp(name, "ContentType") == 0)
+        scanner->ContentTypes = char_to_array(scanner->ContentTypes, &scanner->ContentTypesSize, (SANE_String_Const)xmlNodeGetContent(node), 0);
+    else if (strcmp(name, "DocumentFormat") == 0)
+     {
+        int i = 0;
+        scanner->DocumentFormats = char_to_array(scanner->DocumentFormats, &scanner->DocumentFormatsSize, (SANE_String_Const)xmlNodeGetContent(node), 0);
+        for(; i < scanner->DocumentFormatsSize; i++)
+         {
+            if (scanner->default_format == NULL && !strcmp(scanner->DocumentFormats[i], "image/jpeg"))
+            {
+               scanner->default_format = strdup("image/jpeg");
+            }
+#if(defined HAVE_LIBPNG)
+            else if(!strcmp(scanner->DocumentFormats[i], "image/png") && (scanner->default_format == NULL || strcmp(scanner->default_format, "image/tiff")))
+            {
+               if (scanner->default_format)
+                  free(scanner->default_format);
+               scanner->default_format = strdup("image/png");
+            }
+#endif
+#if(defined HAVE_TIFFIO_H)
+            else if(!strcmp(scanner->DocumentFormats[i], "image/tiff"))
+            {
+               if (scanner->default_format)
+                  free(scanner->default_format);
+               scanner->default_format = strdup("image/tiff");
+            }
+#endif
+         }
+         fprintf(stderr, "Capability : [%s]\n", scanner->default_format);
+     }
+    else if (strcmp(name, "DocumentFormatExt") == 0)
+        scanner->format_ext = 1;
+    else if (strcmp(name, "Intent") == 0)
+        scanner->SupportedIntents = char_to_array(scanner->SupportedIntents, &scanner->SupportedIntentsSize, (SANE_String_Const)xmlNodeGetContent(node), 0);
+    else if (strcmp(name, "XResolution") == 0)
+        scanner->SupportedResolutions = int_to_array(scanner->SupportedResolutions, &scanner->SupportedResolutionsSize, atoi((const char *)xmlNodeGetContent(node)));
+    return (0);
+}
+
+/**
+ * \fn static int find_value_of_int_variables(xmlNode *node, capabilities_t *scanner)
+ * \brief Function that searchs in the xml file if a integer scanner capabilitie is found.
+ *        The integer scanner capabilities that are interesting are :
+ *        MinWidth, MaxWidth, MaxHeight, MinHeight, MaxScanRegions, MaxOpticalXResolution,
+ *        RiskyLeftMargin, RiskyRightMargin, RiskyTopMargin, RiskyBottomMargin.
+ *
+ * \return 0
+ */
+static int
+find_value_of_int_variables(xmlNode *node, capabilities_t *scanner)
+{
+    int MaxWidth = 0;
+    int MaxHeight = 0;
+    const char *name = (const char *)node->name;
+
+    if (strcmp(name, "MinWidth") == 0)
+        scanner->MinWidth = atoi((const char*)xmlNodeGetContent(node));
+    else if (strcmp(name, "MaxWidth") == 0) {
+        MaxWidth = atoi((const char*)xmlNodeGetContent(node));
+        if (scanner->MaxWidth == 0 || MaxWidth < scanner->MaxWidth)
+            scanner->MaxWidth = atoi((const char *)xmlNodeGetContent(node));
+    }
+    else if (strcmp(name, "MinHeight") == 0)
+        scanner->MinHeight = atoi((const char*)xmlNodeGetContent(node));
+    else if (strcmp(name, "MaxHeight") == 0) {
+        MaxHeight = atoi((const char*)xmlNodeGetContent(node));
+        if (scanner->MaxHeight == 0 || MaxHeight < scanner->MaxHeight)
+            scanner->MaxHeight = atoi((const char *)xmlNodeGetContent(node));
+    }
+    else if (strcmp(name, "MaxScanRegions") == 0)
+        scanner->MaxScanRegions = atoi((const char *)xmlNodeGetContent(node));
+    else if (strcmp(name, "MaxOpticalXResolution") == 0)
+        scanner->MaxOpticalXResolution = atoi((const char *)xmlNodeGetContent(node));
+    else if (strcmp(name, "RiskyLeftMargin") == 0)
+        scanner->RiskyLeftMargin = atoi((const char *)xmlNodeGetContent(node));
+    else if (strcmp(name, "RiskyRightMargin") == 0)
+        scanner->RiskyRightMargin = atoi((const char *)xmlNodeGetContent(node));
+    else if (strcmp(name, "RiskyTopMargin") == 0)
+        scanner->RiskyTopMargin = atoi((const char *)xmlNodeGetContent(node));
+    else if (strcmp(name, "RiskyBottomMargin") == 0)
+        scanner->RiskyBottomMargin = atoi((const char *)xmlNodeGetContent(node));
+    find_valor_of_array_variables(node, scanner);
+    return (0);
+}
+
+/**
+ * \fn static int find_true_variables(xmlNode *node, capabilities_t *scanner)
+ * \brief Function that searchs in the xml file if we find a scanner capabilitie stocked
+ *        in one of the created array (character/integer array),
+ *        or, if we find a integer scanner capabilitie.
+ *
+ * \return 0
+ */
+static int
+find_true_variables(xmlNode *node, capabilities_t *scanner)
+{
+    const char *name = (const char *)node->name;
+    if (strcmp(name, "MinWidth") == 0 ||
+        strcmp(name, "MaxWidth") == 0 ||
+        strcmp(name, "MinHeight") == 0 ||
+        strcmp(name, "MaxHeight") == 0 ||
+        strcmp(name, "MaxScanRegions") == 0 ||
+        strcmp(name, "ColorMode") == 0 ||
+        strcmp(name, "ContentType") == 0 ||
+        strcmp(name, "DocumentFormat") == 0 ||
+        strcmp(name, "XResolution") == 0 ||
+        strcmp(name, "Intent") == 0 ||
+        strcmp(name, "MaxOpticalXResolution") == 0 ||
+        strcmp(name, "RiskyLeftMargin") == 0 ||
+        strcmp(name, "RiskyRightMargin") == 0 ||
+        strcmp(name, "RiskyTopMargin") == 0 ||
+        strcmp(name, "RiskyBottomMargin") == 0 ||
+        strcmp(name, "DocumentFormatExt") == 0)
+            find_value_of_int_variables(node, scanner);
+    return (0);
+}
+
+/**
+ * \fn static int print_xml_c(xmlNode *node, capabilities_t *scanner)
+ * \brief Function that browses the xml file, node by node.
+ *
+ * \return 0
+ */
+static int
+print_xml_c(xmlNode *node, capabilities_t *scanner)
+{
+    while (node) {
+        if (node->type == XML_ELEMENT_NODE) {
+            if (find_nodes_c(node))
+                find_true_variables(node, scanner);
+        }
+        print_xml_c(node->children, scanner);
+        node = node->next;
+    }
+    return (0);
+}
+
+/**
+ * \fn capabilities_t *escl_capabilities(SANE_String_Const name, SANE_Status *status)
+ * \brief Function that finally recovers all the capabilities of the scanner, using curl.
+ *        This function is called in the 'sane_open' function and it's the equivalent of
+ *        the following curl command : "curl http(s)://'ip':'port'/eSCL/ScannerCapabilities".
+ *
+ * \return scanner (the structure that stocks all the capabilities elements)
+ */
+capabilities_t *
+escl_capabilities(SANE_String_Const name, SANE_Status *status)
+{
+    capabilities_t *scanner = (capabilities_t*)calloc(1, sizeof(capabilities_t));
+    CURL *curl_handle = NULL;
+    struct cap *var = NULL;
+    xmlDoc *data = NULL;
+    xmlNode *node = NULL;
+    const char *scanner_capabilities = "/eSCL/ScannerCapabilities";
+    char tmp[PATH_MAX] = { 0 };
+
+    *status = SANE_STATUS_GOOD;
+    if (name == NULL)
+        *status = SANE_STATUS_NO_MEM;
+    var = (struct cap *)calloc(1, sizeof(struct cap));
+    if (var == NULL)
+        *status = SANE_STATUS_NO_MEM;
+    var->memory = malloc(1);
+    var->size = 0;
+    curl_handle = curl_easy_init();
+    strcpy(tmp, name);
+    strcat(tmp, scanner_capabilities);
+    DBG( 1, "Get Capabilities : %s\n", tmp);
+    curl_easy_setopt(curl_handle, CURLOPT_URL, tmp);
+    if (strncmp(name, "https", 5) == 0) {
+        DBG( 1, "Ignoring safety certificates, use https\n");
+        curl_easy_setopt(curl_handle, CURLOPT_SSL_VERIFYPEER, 0L);
+        curl_easy_setopt(curl_handle, CURLOPT_SSL_VERIFYHOST, 0L);
+    }
+    curl_easy_setopt(curl_handle, CURLOPT_WRITEFUNCTION, memory_callback_c);
+    curl_easy_setopt(curl_handle, CURLOPT_WRITEDATA, (void *)var);
+    if (curl_easy_perform(curl_handle) != CURLE_OK) {
+        DBG( 1, "The scanner didn't respond.\n");
+        *status = SANE_STATUS_INVAL;
+    }
+    data = xmlReadMemory(var->memory, var->size, "file.xml", NULL, 0);
+    if (data == NULL)
+        *status = SANE_STATUS_NO_MEM;
+    node = xmlDocGetRootElement(data);
+    if (node == NULL)
+        *status = SANE_STATUS_NO_MEM;
+    print_xml_c(node, scanner);
+    xmlFreeDoc(data);
+    xmlCleanupParser();
+    xmlMemoryDump();
+    curl_easy_cleanup(curl_handle);
+    free(var->memory);
+    return (scanner);
+}
diff --git a/backend/escl/escl_devices.c b/backend/escl/escl_devices.c
new file mode 100644
index 0000000..7ecbe31
--- /dev/null
+++ b/backend/escl/escl_devices.c
@@ -0,0 +1,185 @@
+/* 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.  */
+
+#define DEBUG_DECLARE_ONLY
+#include "../include/sane/config.h"
+
+#include "escl.h"
+
+#include <assert.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <avahi-client/lookup.h>
+#include <avahi-common/error.h>
+#include <avahi-common/simple-watch.h>
+
+#include "../include/sane/sanei.h"
+
+static AvahiSimplePoll *simple_poll = NULL;
+
+/**
+ * \fn static void resolve_callback(AvahiServiceResolver *r, AVAHI_GCC_UNUSED
+ * AvahiIfIndex interface, AVAHI_GCC_UNUSED AvahiProtocol protocol,
+ * AvahiResolverEvent event, const char *name,
+ *                            const char *type, const char *domain, const char *host_name,
+ *                            const AvahiAddress *address, uint16_t port,
+ *                            AvahiStringList *txt, AvahiLookupResultFlags flags,
+ *                            void *userdata)
+ * \brief Callback function that will check if the selected scanner follows the escl
+ *  protocol or not.
+ */
+static void
+resolve_callback(AvahiServiceResolver *r, AVAHI_GCC_UNUSED AvahiIfIndex interface,
+                            AVAHI_GCC_UNUSED AvahiProtocol protocol,
+                            AvahiResolverEvent event, const char *name,
+                            const char __sane_unused__ *type,
+                            const char __sane_unused__ *domain,
+                            const char __sane_unused__ *host_name,
+                            const AvahiAddress *address, uint16_t port, AvahiStringList *txt,
+                            AvahiLookupResultFlags __sane_unused__ flags,
+                            void __sane_unused__ *userdata)
+{
+    char a[AVAHI_ADDRESS_STR_MAX], *t;
+    assert(r);
+    switch (event) {
+    case AVAHI_RESOLVER_FAILURE:
+        break;
+    case AVAHI_RESOLVER_FOUND:
+        avahi_address_snprint(a, sizeof(a), address);
+        t = avahi_string_list_to_string(txt);
+        if (strstr(t, "\"rs=eSCL\"") || strstr(t, "\"rs=/eSCL\""))
+            escl_device_add(port, name, a, (char*)type);
+    }
+}
+
+/**
+ * \fn static void browse_callback(AvahiServiceBrowser *b, AvahiIfIndex interface,
+ * AvahiProtocol protocol, AvahiBrowserEvent event, const char *name,
+ * const char *type, const char *domain,
+ *                           AVAHI_GCC_UNUSED AvahiLookupResultFlags flags, void* userdata)
+ * \brief Callback function that will browse tanks to 'avahi' the scanners
+ * connected in network.
+ */
+static void
+browse_callback(AvahiServiceBrowser *b, AvahiIfIndex interface,
+                            AvahiProtocol protocol, AvahiBrowserEvent event,
+                            const char *name, const char *type,
+                            const char *domain,
+                            AVAHI_GCC_UNUSED AvahiLookupResultFlags flags,
+                            void* userdata)
+{
+    AvahiClient *c = userdata;
+    assert(b);
+    switch (event) {
+    case AVAHI_BROWSER_FAILURE:
+        avahi_simple_poll_quit(simple_poll);
+        return;
+    case AVAHI_BROWSER_NEW:
+        if (!(avahi_service_resolver_new(c, interface, protocol, name,
+                                                               type, domain,
+                                                               AVAHI_PROTO_UNSPEC, 0,
+                                                               resolve_callback, c)))
+            break;
+    case AVAHI_BROWSER_REMOVE:
+        break;
+    case AVAHI_BROWSER_ALL_FOR_NOW:
+    case AVAHI_BROWSER_CACHE_EXHAUSTED:
+        if (event != AVAHI_BROWSER_CACHE_EXHAUSTED)
+            avahi_simple_poll_quit(simple_poll);
+        break;
+    }
+}
+
+/**
+ * \fn static void client_callback(AvahiClient *c, AvahiClientState state,
+ * AVAHI_GCC_UNUSED void *userdata)
+ * \brief Callback Function that quit if it doesn't find a connected scanner,
+ * possible thanks the "Hello Protocol".
+ *        --> Waiting for a answer by the scanner to continue the avahi process.
+ */
+static void
+client_callback(AvahiClient *c, AvahiClientState state,
+                         AVAHI_GCC_UNUSED void *userdata)
+{
+    assert(c);
+    if (state == AVAHI_CLIENT_FAILURE)
+        avahi_simple_poll_quit(simple_poll);
+}
+
+/**
+ * \fn ESCL_Device *escl_devices(SANE_Status *status)
+ * \brief Function that calls all the avahi functions and then, recovers the
+ * connected eSCL devices.
+ *        This function is called in the 'sane_get_devices' function.
+ *
+ * \return NULL (the eSCL devices found)
+ */
+ESCL_Device *
+escl_devices(SANE_Status *status)
+{
+    AvahiClient *client = NULL;
+    AvahiServiceBrowser *sb = NULL;
+    int error;
+
+    *status = SANE_STATUS_GOOD;
+    if (!(simple_poll = avahi_simple_poll_new())) {
+        DBG( 1, "Failed to create simple poll object.\n");
+        *status = SANE_STATUS_INVAL;
+        goto fail;
+    }
+    client = avahi_client_new(avahi_simple_poll_get(simple_poll), 0,
+                                               client_callback, NULL, &error);
+    if (!client) {
+        DBG( 1, "Failed to create client: %s\n", avahi_strerror(error));
+        *status = SANE_STATUS_INVAL;
+        goto fail;
+    }
+    if (!(sb = avahi_service_browser_new(client, AVAHI_IF_UNSPEC,
+                                                                   AVAHI_PROTO_UNSPEC, "_uscan._tcp",
+                                                                   NULL, 0, browse_callback, client))) {
+        DBG( 1, "Failed to create service browser: %s\n",
+                              avahi_strerror(avahi_client_errno(client)));
+        *status = SANE_STATUS_INVAL;
+        goto fail;
+    }
+    if (!(sb = avahi_service_browser_new(client, AVAHI_IF_UNSPEC,
+                                                                   AVAHI_PROTO_UNSPEC,
+                                                                   "_uscans._tcp", NULL, 0,
+                                                                   browse_callback, client))) {
+        DBG( 1, "Failed to create service browser: %s\n",
+                                avahi_strerror(avahi_client_errno(client)));
+        *status = SANE_STATUS_INVAL;
+        goto fail;
+    }
+    avahi_simple_poll_loop(simple_poll);
+fail:
+    if (sb)
+        avahi_service_browser_free(sb);
+    if (client)
+        avahi_client_free(client);
+    if (simple_poll)
+        avahi_simple_poll_free(simple_poll);
+    return (NULL);
+}
diff --git a/backend/escl/escl_jpeg.c b/backend/escl/escl_jpeg.c
new file mode 100644
index 0000000..d6287ef
--- /dev/null
+++ b/backend/escl/escl_jpeg.c
@@ -0,0 +1,230 @@
+/* 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.  */
+
+#define DEBUG_DECLARE_ONLY
+#include "../include/sane/config.h"
+
+#include  "escl.h"
+
+#include "../include/sane/sanei.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#if(defined HAVE_LIBJPEG)
+#  include <jpeglib.h>
+#endif
+
+#include <setjmp.h>
+
+#define INPUT_BUFFER_SIZE 4096
+
+#if(defined HAVE_LIBJPEG)
+struct my_error_mgr
+{
+    struct jpeg_error_mgr errmgr;
+    jmp_buf escape;
+};
+
+typedef struct
+{
+    struct jpeg_source_mgr pub;
+    FILE *ctx;
+    unsigned char buffer[INPUT_BUFFER_SIZE];
+} my_source_mgr;
+
+/**
+ * \fn static boolean fill_input_buffer(j_decompress_ptr cinfo)
+ * \brief Called in the "skip_input_data" function.
+ *
+ * \return TRUE (everything is OK)
+ */
+static boolean
+fill_input_buffer(j_decompress_ptr cinfo)
+{
+    my_source_mgr *src = (my_source_mgr *) cinfo->src;
+    int nbytes = 0;
+
+    nbytes = fread(src->buffer, 1, INPUT_BUFFER_SIZE, src->ctx);
+    if (nbytes <= 0) {
+        src->buffer[0] = (unsigned char) 0xFF;
+        src->buffer[1] = (unsigned char) JPEG_EOI;
+        nbytes = 2;
+    }
+    src->pub.next_input_byte = src->buffer;
+    src->pub.bytes_in_buffer = nbytes;
+    return (TRUE);
+}
+
+/**
+ * \fn static void skip_input_data(j_decompress_ptr cinfo, long num_bytes)
+ * \brief Called in the "jpeg_RW_src" function.
+ */
+static void
+skip_input_data(j_decompress_ptr cinfo, long num_bytes)
+{
+    my_source_mgr *src = (my_source_mgr *) cinfo->src;
+
+    if (num_bytes > 0) {
+        while (num_bytes > (long) src->pub.bytes_in_buffer) {
+            num_bytes -= (long) src->pub.bytes_in_buffer;
+            (void) src->pub.fill_input_buffer(cinfo);
+        }
+        src->pub.next_input_byte += (size_t) num_bytes;
+        src->pub.bytes_in_buffer -= (size_t) num_bytes;
+    }
+}
+
+static void
+term_source(j_decompress_ptr __sane_unused__ cinfo)
+{
+    return;
+}
+
+static void
+init_source(j_decompress_ptr __sane_unused__ cinfo)
+{
+    return;
+}
+
+/**
+ * \fn static void jpeg_RW_src(j_decompress_ptr cinfo, FILE *ctx)
+ * \brief Called in the "escl_sane_decompressor" function.
+ */
+static void
+jpeg_RW_src(j_decompress_ptr cinfo, FILE *ctx)
+{
+    my_source_mgr *src;
+
+    if (cinfo->src == NULL) {
+        cinfo->src = (struct jpeg_source_mgr *)(*cinfo->mem->alloc_small)
+            ((j_common_ptr) cinfo, JPOOL_PERMANENT, sizeof(my_source_mgr));
+        src = (my_source_mgr *) cinfo->src;
+    }
+    src = (my_source_mgr *) cinfo->src;
+    src->pub.init_source = init_source;
+    src->pub.fill_input_buffer = fill_input_buffer;
+    src->pub.skip_input_data = skip_input_data;
+    src->pub.resync_to_restart = jpeg_resync_to_restart;
+    src->pub.term_source = term_source;
+    src->ctx = ctx;
+    src->pub.bytes_in_buffer = 0;
+    src->pub.next_input_byte = NULL;
+}
+
+static void
+my_error_exit(j_common_ptr cinfo)
+{
+    struct my_error_mgr *err = (struct my_error_mgr *)cinfo->err;
+
+    longjmp(err->escape, 1);
+}
+
+static void
+output_no_message(j_common_ptr __sane_unused__ cinfo)
+{
+}
+
+/**
+ * \fn SANE_Status escl_sane_decompressor(escl_sane_t *handler)
+ * \brief Function that aims to decompress the jpeg image to SANE be able to read the image.
+ *        This function is called in the "sane_read" function.
+ *
+ * \return SANE_STATUS_GOOD (if everything is OK, otherwise, SANE_STATUS_NO_MEM/SANE_STATUS_INVAL)
+ */
+SANE_Status
+get_JPEG_data(capabilities_t *scanner, int *w, int *h, int *bps)
+{
+    int start = 0;
+    struct jpeg_decompress_struct cinfo;
+    JSAMPROW rowptr[1];
+    unsigned char *surface = NULL;
+    struct my_error_mgr jerr;
+    int lineSize = 0;
+
+    if (scanner->tmp == NULL)
+        return (SANE_STATUS_INVAL);
+    fseek(scanner->tmp, SEEK_SET, 0);
+    start = ftell(scanner->tmp);
+    cinfo.err = jpeg_std_error(&jerr.errmgr);
+    jerr.errmgr.error_exit = my_error_exit;
+    jerr.errmgr.output_message = output_no_message;
+    if (setjmp(jerr.escape)) {
+        jpeg_destroy_decompress(&cinfo);
+        if (surface != NULL)
+            free(surface);
+        DBG( 1, "Escl Jpeg : Error reading jpeg\n");
+        if (scanner->tmp) {
+           fclose(scanner->tmp);
+           scanner->tmp = NULL;
+        }
+        return (SANE_STATUS_INVAL);
+    }
+    jpeg_create_decompress(&cinfo);
+    jpeg_RW_src(&cinfo, scanner->tmp);
+    jpeg_read_header(&cinfo, TRUE);
+    cinfo.out_color_space = JCS_RGB;
+    cinfo.quantize_colors = FALSE;
+    jpeg_calc_output_dimensions(&cinfo);
+    surface = malloc(cinfo.output_width * cinfo.output_height * cinfo.output_components);
+    if (surface == NULL) {
+        jpeg_destroy_decompress(&cinfo);
+        fseek(scanner->tmp, start, SEEK_SET);
+        DBG( 1, "Escl Jpeg : Memory allocation problem\n");
+        if (scanner->tmp) {
+           fclose(scanner->tmp);
+           scanner->tmp = NULL;
+        }
+        return (SANE_STATUS_NO_MEM);
+    }
+    lineSize = cinfo.output_width * cinfo.output_components;
+    jpeg_start_decompress(&cinfo);
+    while (cinfo.output_scanline < cinfo.output_height) {
+        rowptr[0] = (JSAMPROW)surface + (lineSize * cinfo.output_scanline);
+        jpeg_read_scanlines(&cinfo, rowptr, (JDIMENSION) 1);
+    }
+    scanner->img_data = surface;
+    scanner->img_size = lineSize * cinfo.output_height;
+    scanner->img_read = 0;
+    *w = cinfo.output_width;
+    *h = cinfo.output_height;
+    *bps = cinfo.output_components;
+    jpeg_finish_decompress(&cinfo);
+    jpeg_destroy_decompress(&cinfo);
+    fclose(scanner->tmp);
+    scanner->tmp = NULL;
+    return (SANE_STATUS_GOOD);
+}
+#else
+
+SANE_Status
+get_JPEG_data(capabilities_t __sane_unused__ *scanner,
+              int __sane_unused__ *w,
+              int __sane_unused__ *h,
+              int __sane_unused__ *bps)
+{
+    return (SANE_STATUS_INVAL);
+}
+
+#endif
diff --git a/backend/escl/escl_newjob.c b/backend/escl/escl_newjob.c
new file mode 100644
index 0000000..279b9df
--- /dev/null
+++ b/backend/escl/escl_newjob.c
@@ -0,0 +1,241 @@
+/* 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.  */
+
+#define DEBUG_DECLARE_ONLY
+#include "../include/sane/config.h"
+
+#include "escl.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <curl/curl.h>
+
+#ifdef PATH_MAX
+# undef PATH_MAX
+#endif
+
+#define PATH_MAX 4096
+
+struct uploading
+{
+    const char *read_data;
+    size_t size;
+};
+
+struct downloading
+{
+    char *memory;
+    size_t size;
+};
+
+static const char settings[] =
+    "<?xml version=\"1.0\" encoding=\"UTF-8\"?>"                        \
+    "<scan:ScanSettings xmlns:pwg=\"http://www.pwg.org/schemas/2010/12/sm\" xmlns:scan=\"http://schemas.hp.com/imaging/escl/2011/05/03\">" \
+    "   <pwg:Version>2.0</pwg:Version>" \
+    "   <pwg:ScanRegions>" \
+    "      <pwg:ScanRegion>" \
+    "          <pwg:ContentRegionUnits>escl:ThreeHundredthsOfInches</pwg:ContentRegionUnits>" \
+    "          <pwg:Height>%d</pwg:Height>" \
+    "          <pwg:Width>%d</pwg:Width>" \
+    "          <pwg:XOffset>%d</pwg:XOffset>" \
+    "          <pwg:YOffset>%d</pwg:YOffset>" \
+    "      </pwg:ScanRegion>" \
+    "   </pwg:ScanRegions>" \
+    "   <pwg:DocumentFormat>%s</pwg:DocumentFormat>" \
+    "%s" \
+    "   <scan:ColorMode>%s</scan:ColorMode>" \
+    "   <scan:XResolution>%d</scan:XResolution>" \
+    "   <scan:YResolution>%d</scan:YResolution>" \
+    "   <pwg:InputSource>Platen</pwg:InputSource>" \
+    "</scan:ScanSettings>";
+
+static char formatExtJPEG[] =
+    "   <scan:DocumentFormatExt>image/jpeg</scan:DocumentFormatExt>";
+
+static char formatExtPNG[] =
+    "   <scan:DocumentFormatExt>image/png</scan:DocumentFormatExt>";
+
+static char formatExtTIFF[] =
+    "   <scan:DocumentFormatExt>image/tiff</scan:DocumentFormatExt>";
+
+/**
+ * \fn static size_t download_callback(void *str, size_t size, size_t nmemb, void *userp)
+ * \brief Callback function that stocks in memory the content of the 'job'. Example below :
+ *        "Trying 192.168.14.150...
+ *         TCP_NODELAY set
+ *         Connected to 192.168.14.150 (192.168.14.150) port 80
+ *         POST /eSCL/ScanJobs HTTP/1.1
+ *         Host: 192.168.14.150
+ *         User-Agent: curl/7.55.1
+ *         Accept: /
+ *         Content-Length: 605
+ *         Content-Type: application/x-www-form-urlencoded
+ *         upload completely sent off: 605 out of 605 bytes
+ *         < HTTP/1.1 201 Created
+ *         < MIME-Version: 1.0
+ *         < Location: http://192.168.14.150/eSCL/ScanJobs/22b54fd0-027b-1000-9bd0-f4a99726e2fa
+ *         < Content-Length: 0
+ *         < Connection: close
+ *         <
+ *         Closing connection 0"
+ *
+ * \return realsize (size of the content needed -> the 'job')
+ */
+static size_t
+download_callback(void *str, size_t size, size_t nmemb, void *userp)
+{
+    struct downloading *download = (struct downloading *)userp;
+    size_t realsize = size * nmemb;
+    char *content = realloc(download->memory, download->size + realsize + 1);
+
+    if (content == NULL) {
+        DBG( 1, "Not enough memory (realloc returned NULL)\n");
+        return (0);
+    }
+    download->memory = content;
+    memcpy(&(download->memory[download->size]), str, realsize);
+    download->size = download->size + realsize;
+    download->memory[download->size] = 0;
+    return (realsize);
+}
+
+/**
+ * \fn char *escl_newjob (capabilities_t *scanner, SANE_String_Const name, SANE_Status *status)
+ * \brief Function that, using curl, uploads the data (composed by the scanner capabilities) to the
+ *        server to download the 'job' and recover the 'new job' (char *result), in LOCATION.
+ *        This function is called in the 'sane_start' function and it's the equivalent of the
+ *        following curl command : "curl -v POST -d cap.xml http(s)://'ip':'port'/eSCL/ScanJobs".
+ *
+ * \return result (the 'new job', situated in LOCATION)
+ */
+char *
+escl_newjob (capabilities_t *scanner, SANE_String_Const name, SANE_Status *status)
+{
+    CURL *curl_handle = NULL;
+    struct uploading *upload = NULL;
+    struct downloading *download = NULL;
+    const char *scan_jobs = "/eSCL/ScanJobs";
+    char cap_data[PATH_MAX] = { 0 };
+    char job_cmd[PATH_MAX] = { 0 };
+    char *location = NULL;
+    char *result = NULL;
+    char *temporary = NULL;
+    char *f_ext = "";
+    char *format_ext = NULL;
+
+    *status = SANE_STATUS_GOOD;
+    if (name == NULL || scanner == NULL) {
+        *status = SANE_STATUS_NO_MEM;
+        DBG( 1, "Create NewJob : the name or the scan are invalid.\n");
+        return (NULL);
+    }
+    upload = (struct uploading *)calloc(1, sizeof(struct uploading));
+    if (upload == NULL) {
+        *status = SANE_STATUS_NO_MEM;
+        DBG( 1, "Create NewJob : memory allocation failure\n");
+        return (NULL);
+    }
+    download = (struct downloading *)calloc(1, sizeof(struct downloading));
+    if (download == NULL) {
+        free(upload);
+        DBG( 1, "Create NewJob : memory allocation failure\n");
+        *status = SANE_STATUS_NO_MEM;
+        return (NULL);
+    }
+    curl_handle = curl_easy_init();
+    if (scanner->format_ext == 1)
+    {
+       if (!strcmp(scanner->default_format, "image/jpeg"))
+          format_ext = formatExtJPEG;
+       else if (!strcmp(scanner->default_format, "image/png"))
+          format_ext = formatExtPNG;
+       else if (!strcmp(scanner->default_format, "image/tiff"))
+          format_ext = formatExtTIFF;
+       else
+          format_ext = f_ext;
+    }
+    else
+      format_ext = f_ext;
+    DBG( 1, "Create NewJob : %s\n", scanner->default_format);
+    if (curl_handle != NULL) {
+        snprintf(cap_data, sizeof(cap_data), settings, scanner->height, scanner->width, 0, 0, scanner->default_format,
+                 format_ext,
+                 scanner->default_color, scanner->default_resolution, scanner->default_resolution);
+        DBG( 1, "Create NewJob : %s\n", cap_data);
+        upload->read_data = strdup(cap_data);
+        upload->size = strlen(cap_data);
+        download->memory = malloc(1);
+        download->size = 0;
+        strcpy(job_cmd, name);
+        strcat(job_cmd, scan_jobs);
+        curl_easy_setopt(curl_handle, CURLOPT_URL, job_cmd);
+        if (strncmp(name, "https", 5) == 0) {
+            curl_easy_setopt(curl_handle, CURLOPT_SSL_VERIFYPEER, 0L);
+            curl_easy_setopt(curl_handle, CURLOPT_SSL_VERIFYHOST, 0L);
+        }
+        curl_easy_setopt(curl_handle, CURLOPT_POST, 1L);
+        curl_easy_setopt(curl_handle, CURLOPT_POSTFIELDS, upload->read_data);
+        curl_easy_setopt(curl_handle, CURLOPT_POSTFIELDSIZE, upload->size);
+        curl_easy_setopt(curl_handle, CURLOPT_HEADERFUNCTION, download_callback);
+        curl_easy_setopt(curl_handle, CURLOPT_HEADERDATA, (void *)download);
+        if (curl_easy_perform(curl_handle) != CURLE_OK) {
+            DBG( 1, "Create NewJob : the scanner responded incorrectly.\n");
+            *status = SANE_STATUS_INVAL;
+        }
+        else {
+            if (download->memory != NULL) {
+                if (strstr(download->memory, "Location:")) {
+                    temporary = strrchr(download->memory, '/');
+                    if (temporary != NULL) {
+                        location = strchr(temporary, '\r');
+                        if (location == NULL)
+                            location = strchr(temporary, '\n');
+                        else {
+                            *location = '\0';
+                            result = strdup(temporary);
+                        }
+                       DBG( 1, "Create NewJob : %s\n", result);
+                    }
+                    free(download->memory);
+                }
+                else {
+                    DBG( 1, "Create NewJob : The creation of the failed job\n");
+                    *status = SANE_STATUS_INVAL;
+                }
+            }
+            else {
+                *status = SANE_STATUS_NO_MEM;
+                DBG( 1, "Create NewJob : The creation of the failed job\n");
+                return (NULL);
+            }
+        }
+        curl_easy_cleanup(curl_handle);
+    }
+    if (upload != NULL)
+        free(upload);
+    if (download != NULL)
+        free(download);
+    return (result);
+}
diff --git a/backend/escl/escl_png.c b/backend/escl/escl_png.c
new file mode 100644
index 0000000..18f6f35
--- /dev/null
+++ b/backend/escl/escl_png.c
@@ -0,0 +1,193 @@
+/* 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.  */
+
+#define DEBUG_DECLARE_ONLY
+#include "../include/sane/config.h"
+
+#include "escl.h"
+
+#include "../include/sane/sanei.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#if(defined HAVE_LIBPNG)
+#include <png.h>
+#endif
+
+#include <setjmp.h>
+
+
+#if(defined HAVE_LIBPNG)
+
+/**
+ * \fn SANE_Status escl_sane_decompressor(escl_sane_t *handler)
+ * \brief Function that aims to decompress the png image to SANE be able to read the image.
+ *        This function is called in the "sane_read" function.
+ *
+ * \return SANE_STATUS_GOOD (if everything is OK, otherwise, SANE_STATUS_NO_MEM/SANE_STATUS_INVAL)
+ */
+SANE_Status
+get_PNG_data(capabilities_t *scanner, int *w, int *h, int *components)
+{
+	unsigned int  width = 0;           /* largeur */
+	unsigned int  height = 0;          /* hauteur */
+	int           bps = 3;  /* composantes d'un texel */
+	unsigned char *texels = NULL;         /* données de l'image */
+        unsigned int i = 0;
+	png_byte magic[8];
+
+	// read magic number
+	fread (magic, 1, sizeof (magic), scanner->tmp);
+	// check for valid magic number
+	if (!png_check_sig (magic, sizeof (magic)))
+	{
+		DBG( 1, "Escl Png : PNG error is not a valid PNG image!\n");
+                if (scanner->tmp) {
+                   fclose(scanner->tmp);
+                   scanner->tmp = NULL;
+                }
+		return (SANE_STATUS_INVAL);
+	}
+	// create a png read struct
+	png_structp png_ptr = png_create_read_struct
+		(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
+	if (!png_ptr)
+	{
+		DBG( 1, "Escl Png : PNG error create a png read struct\n");
+                if (scanner->tmp)
+                if (scanner->tmp) {
+                   fclose(scanner->tmp);
+                   scanner->tmp = NULL;
+                }
+		return (SANE_STATUS_INVAL);
+	}
+	// create a png info struct
+	png_infop info_ptr = png_create_info_struct (png_ptr);
+	if (!info_ptr)
+	{
+		DBG( 1, "Escl Png : PNG error create a png info struct\n");
+		png_destroy_read_struct (&png_ptr, NULL, NULL);
+                if (scanner->tmp) {
+                   fclose(scanner->tmp);
+                   scanner->tmp = NULL;
+                }
+		return (SANE_STATUS_INVAL);
+	}
+	// initialize the setjmp for returning properly after a libpng
+	//   error occured
+	if (setjmp (png_jmpbuf (png_ptr)))
+	{
+		png_destroy_read_struct (&png_ptr, &info_ptr, NULL);
+		if (texels)
+		  free (texels);
+        fprintf(stderr,"PNG read error.\n");
+                if (scanner->tmp) {
+                   fclose(scanner->tmp);
+                   scanner->tmp = NULL;
+                }
+		DBG( 1, "Escl Png : PNG read error.\n");
+		return (SANE_STATUS_INVAL);
+	}
+	// setup libpng for using standard C fread() function
+	//   with our FILE pointer
+	png_init_io (png_ptr, scanner->tmp);
+	// tell libpng that we have already read the magic number
+	png_set_sig_bytes (png_ptr, sizeof (magic));
+
+	// read png info
+	png_read_info (png_ptr, info_ptr);
+
+	int bit_depth, color_type;
+	// get some usefull information from header
+	bit_depth = png_get_bit_depth (png_ptr, info_ptr);
+	color_type = png_get_color_type (png_ptr, info_ptr);
+	// convert index color images to RGB images
+	if (color_type == PNG_COLOR_TYPE_PALETTE)
+		png_set_palette_to_rgb (png_ptr);
+	else if (color_type != PNG_COLOR_TYPE_RGB && color_type != PNG_COLOR_TYPE_RGB_ALPHA)
+	{
+        fprintf(stderr,"PNG format not supported.\n");
+                if (scanner->tmp) {
+                   fclose(scanner->tmp);
+                   scanner->tmp = NULL;
+                }
+		return (SANE_STATUS_INVAL);
+	}
+    if (color_type ==  PNG_COLOR_TYPE_RGB_ALPHA)
+        bps = 4;
+    else
+	    bps = 3;
+	if (png_get_valid (png_ptr, info_ptr, PNG_INFO_tRNS))
+		png_set_tRNS_to_alpha (png_ptr);
+	if (bit_depth == 16)
+		png_set_strip_16 (png_ptr);
+	else if (bit_depth < 8)
+		png_set_packing (png_ptr);
+	// update info structure to apply transformations
+	png_read_update_info (png_ptr, info_ptr);
+	// retrieve updated information
+	png_get_IHDR (png_ptr, info_ptr,
+			(png_uint_32*)(&width),
+			(png_uint_32*)(&height),
+			&bit_depth, &color_type,
+			NULL, NULL, NULL);
+
+    *w = (int)width;
+    *h = (int)height;
+    *components = bps;
+	// we can now allocate memory for storing pixel data
+	texels = (unsigned char *)malloc (sizeof (unsigned char) * width
+			* height * bps);
+	png_bytep *row_pointers;
+	// setup a pointer array.  Each one points at the begening of a row.
+	row_pointers = (png_bytep *)malloc (sizeof (png_bytep) * height);
+	for (i = 0; i < height; ++i)
+	{
+		row_pointers[i] = (png_bytep)(texels +
+				((height - (i + 1)) * width * bps));
+	}
+	// read pixel data using row pointers
+	png_read_image (png_ptr, row_pointers);
+	// we don't need row pointers anymore
+	scanner->img_data = texels;
+    scanner->img_size = (int)(width * height * bps);
+    scanner->img_read = 0;
+	free (row_pointers);
+    fclose(scanner->tmp);
+    scanner->tmp = NULL;
+    return (SANE_STATUS_GOOD);
+}
+#else
+
+SANE_Status
+get_PNG_data(capabilities_t __sane_unused__ *scanner,
+              int __sane_unused__ *w,
+              int __sane_unused__ *h,
+              int __sane_unused__ *bps)
+{
+    return (SANE_STATUS_INVAL);
+}
+
+#endif
diff --git a/backend/escl/escl_reset.c b/backend/escl/escl_reset.c
new file mode 100644
index 0000000..7722d89
--- /dev/null
+++ b/backend/escl/escl_reset.c
@@ -0,0 +1,75 @@
+/* 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.  */
+
+#define DEBUG_DECLARE_ONLY
+#include "../include/sane/config.h"
+
+#include "escl.h"
+
+#include <stdlib.h>
+#include <string.h>
+
+#include <curl/curl.h>
+
+/**
+ * \fn void escl_scanner(SANE_String_Const name, char *result)
+ * \brief Function that resets the scanner after each scan, using curl.
+ *        This function is called in the 'sane_cancel' function.
+ */
+void
+escl_scanner(SANE_String_Const name, char *result)
+{
+    CURL *curl_handle = NULL;
+    const char *scan_jobs = "/eSCL/ScanJobs";
+    const char *scanner_start = "/NextDocument";
+    char scan_cmd[PATH_MAX] = { 0 };
+    int i = 0;
+    long answer = 0;
+
+    if (name == NULL || result == NULL)
+        return;
+CURL_CALL:
+    curl_handle = curl_easy_init();
+    if (curl_handle != NULL) {
+        strcpy(scan_cmd, name);
+        strcat(scan_cmd, scan_jobs);
+        strcat(scan_cmd, result);
+        strcat(scan_cmd, scanner_start);
+        curl_easy_setopt(curl_handle, CURLOPT_URL, scan_cmd);
+        DBG( 1, "Reset Job : %s.\n", scan_cmd);
+        if (strncmp(name, "https", 5) == 0) {
+            DBG( 1, "Ignoring safety certificates, use https\n");
+            curl_easy_setopt(curl_handle, CURLOPT_SSL_VERIFYPEER, 0L);
+            curl_easy_setopt(curl_handle, CURLOPT_SSL_VERIFYHOST, 0L);
+        }
+        if (curl_easy_perform(curl_handle) == CURLE_OK) {
+            curl_easy_getinfo(curl_handle, CURLINFO_RESPONSE_CODE, &answer);
+            if (i < 3 && answer == 503) {
+                curl_easy_cleanup(curl_handle);
+                i++;
+                goto CURL_CALL;
+            }
+        }
+        curl_easy_cleanup(curl_handle);
+    }
+}
diff --git a/backend/escl/escl_scan.c b/backend/escl/escl_scan.c
new file mode 100644
index 0000000..8f077a1
--- /dev/null
+++ b/backend/escl/escl_scan.c
@@ -0,0 +1,99 @@
+/* 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.  */
+
+#define DEBUG_DECLARE_ONLY
+#include "../include/sane/config.h"
+
+#include "escl.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <curl/curl.h>
+
+#include "../include/sane/sanei.h"
+
+/**
+ * \fn static size_t write_callback(void *str, size_t size, size_t nmemb, void *userp)
+ * \brief Callback function that writes the image scanned into the temporary file.
+ *
+ * \return to_write (the result of the fwrite fonction)
+ */
+static size_t
+write_callback(void *str, size_t size, size_t nmemb, void *userp)
+{
+    size_t to_write = fwrite(str, size, nmemb, (FILE *)userp);
+
+    return (to_write);
+}
+
+/**
+ * \fn SANE_Status escl_scan(capabilities_t *scanner, SANE_String_Const name, char *result)
+ * \brief Function that, after recovering the 'new job', scans the image writed in the
+ *        temporary file, using curl.
+ *        This function is called in the 'sane_start' function and it's the equivalent of
+ *        the following curl command : "curl -s http(s)://'ip:'port'/eSCL/ScanJobs/'new job'/NextDocument > image.jpg".
+ *
+ * \return status (if everything is OK, status = SANE_STATUS_GOOD, otherwise, SANE_STATUS_NO_MEM/SANE_STATUS_INVAL)
+ */
+SANE_Status
+escl_scan(capabilities_t __sane_unused__ *scanner, SANE_String_Const name, char *result)
+{
+    CURL *curl_handle = NULL;
+    const char *scan_jobs = "/eSCL/ScanJobs";
+    const char *scanner_start = "/NextDocument";
+    char scan_cmd[PATH_MAX] = { 0 };
+    SANE_Status status = SANE_STATUS_GOOD;
+
+    if (name == NULL)
+        return (SANE_STATUS_NO_MEM);
+    curl_handle = curl_easy_init();
+    if (curl_handle != NULL) {
+        strcpy(scan_cmd, name);
+        strcat(scan_cmd, scan_jobs);
+        strcat(scan_cmd, result);
+        strcat(scan_cmd, scanner_start);
+        curl_easy_setopt(curl_handle, CURLOPT_URL, scan_cmd);
+        DBG( 1, "Scan : %s.\n", scan_cmd);
+	if (strncmp(name, "https", 5) == 0) {
+            DBG( 1, "Ignoring safety certificates, use https\n");
+            curl_easy_setopt(curl_handle, CURLOPT_SSL_VERIFYPEER, 0L);
+            curl_easy_setopt(curl_handle, CURLOPT_SSL_VERIFYHOST, 0L);
+        }
+        curl_easy_setopt(curl_handle, CURLOPT_WRITEFUNCTION, write_callback);
+        scanner->tmp = tmpfile();
+        if (scanner->tmp != NULL) {
+            curl_easy_setopt(curl_handle, CURLOPT_WRITEDATA, scanner->tmp);
+            if (curl_easy_perform(curl_handle) != CURLE_OK) {
+                status = SANE_STATUS_INVAL;
+            }
+            else
+                curl_easy_cleanup(curl_handle);
+            fseek(scanner->tmp, 0, SEEK_SET);
+        }
+        else
+            status = SANE_STATUS_NO_MEM;
+    }
+    return (status);
+}
diff --git a/backend/escl/escl_status.c b/backend/escl/escl_status.c
new file mode 100644
index 0000000..68b51dc
--- /dev/null
+++ b/backend/escl/escl_status.c
@@ -0,0 +1,176 @@
+/* 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.  */
+
+#define DEBUG_DECLARE_ONLY
+#include "../include/sane/config.h"
+
+#include "escl.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <curl/curl.h>
+#include <libxml/parser.h>
+
+struct idle
+{
+    char *memory;
+    size_t size;
+};
+
+/**
+ * \fn static size_t memory_callback_s(void *contents, size_t size, size_t nmemb, void *userp)
+ * \brief Callback function that stocks in memory the content of the scanner status.
+ *
+ * \return realsize (size of the content needed -> the scanner status)
+ */
+static size_t
+memory_callback_s(void *contents, size_t size, size_t nmemb, void *userp)
+{
+    size_t realsize = size * nmemb;
+    struct idle *mem = (struct idle *)userp;
+
+    char *str = realloc(mem->memory, mem->size + realsize + 1);
+    if (str == NULL) {
+        DBG(1, "not enough memory (realloc returned NULL)\n");
+        return (0);
+    }
+    mem->memory = str;
+    memcpy(&(mem->memory[mem->size]), contents, realsize);
+    mem->size = mem->size + realsize;
+    mem->memory[mem->size] = 0;
+    return (realsize);
+}
+
+/**
+ * \fn static int find_nodes_s(xmlNode *node)
+ * \brief Function that browses the xml file and parses it, to find the xml children node.
+ *        --> to recover the scanner status.
+ *
+ * \return 0 if a xml child node is found, 1 otherwise
+ */
+static int
+find_nodes_s(xmlNode *node)
+{
+    xmlNode *child = node->children;
+
+    while (child) {
+        if (child->type == XML_ELEMENT_NODE)
+            return (0);
+        child = child->next;
+    }
+    return (1);
+}
+
+/**
+ * \fn static void print_xml_s(xmlNode *node, SANE_Status *status)
+ * \brief Function that browses the xml file, node by node.
+ *        If the node 'State' is found, we are expecting to found in this node the 'Idle'
+ *        content (if the scanner is ready to use) and then 'status' = SANE_STATUS_GOOD.
+ *        Otherwise, this means that the scanner isn't ready to use.
+ */
+static void
+print_xml_s(xmlNode *node, SANE_Status *status)
+{
+    int x = 0;
+
+    while (node) {
+        if (node->type == XML_ELEMENT_NODE) {
+            if (find_nodes_s(node)) {
+                if (strcmp((const char *)node->name, "State") == 0)
+                    x = 1;
+            }
+            if (x == 1 && strcmp((const char *)xmlNodeGetContent(node), "Idle") == 0)
+                *status = SANE_STATUS_GOOD;
+        }
+        print_xml_s(node->children, status);
+        node = node->next;
+    }
+}
+
+/**
+ * \fn SANE_Status escl_status(SANE_String_Const name)
+ * \brief Function that finally recovers the scanner status ('Idle', or not), using curl.
+ *        This function is called in the 'sane_open' function and it's the equivalent of
+ *        the following curl command : "curl http(s)://'ip':'port'/eSCL/ScannerStatus".
+ *
+ * \return status (if everything is OK, status = SANE_STATUS_GOOD, otherwise, SANE_STATUS_NO_MEM/SANE_STATUS_INVAL)
+ */
+SANE_Status
+escl_status(SANE_String_Const name)
+{
+    SANE_Status status;
+    CURL *curl_handle = NULL;
+    struct idle *var = NULL;
+    xmlDoc *data = NULL;
+    xmlNode *node = NULL;
+    const char *scanner_status = "/eSCL/ScannerStatus";
+    char tmp[PATH_MAX] = { 0 };
+
+    if (name == NULL)
+        return (SANE_STATUS_NO_MEM);
+    var = (struct idle*)calloc(1, sizeof(struct idle));
+    if (var == NULL)
+        return (SANE_STATUS_NO_MEM);
+    var->memory = malloc(1);
+    var->size = 0;
+    curl_handle = curl_easy_init();
+    strcpy(tmp, name);
+    strcat(tmp, scanner_status);
+    curl_easy_setopt(curl_handle, CURLOPT_URL, tmp);
+    DBG( 1, "Get Status : %s.\n", tmp);
+    if (strncmp(name, "https", 5) == 0) {
+        DBG( 1, "Ignoring safety certificates, use https\n");
+        curl_easy_setopt(curl_handle, CURLOPT_SSL_VERIFYPEER, 0L);
+        curl_easy_setopt(curl_handle, CURLOPT_SSL_VERIFYHOST, 0L);
+    }
+    curl_easy_setopt(curl_handle, CURLOPT_WRITEFUNCTION, memory_callback_s);
+    curl_easy_setopt(curl_handle, CURLOPT_WRITEDATA, (void *)var);
+    if (curl_easy_perform(curl_handle) != CURLE_OK) {
+        DBG( 1, "The scanner didn't respond.\n");
+        status = SANE_STATUS_INVAL;
+        goto clean_data;
+    }
+    data = xmlReadMemory(var->memory, var->size, "file.xml", NULL, 0);
+    if (data == NULL) {
+        status = SANE_STATUS_NO_MEM;
+        goto clean_data;
+    }
+    node = xmlDocGetRootElement(data);
+    if (node == NULL) {
+        status = SANE_STATUS_NO_MEM;
+        goto clean;
+    }
+    status = SANE_STATUS_DEVICE_BUSY;
+    print_xml_s(node, &status);
+clean:
+    xmlFreeDoc(data);
+clean_data:
+    xmlCleanupParser();
+    xmlMemoryDump();
+    curl_easy_cleanup(curl_handle);
+    free(var->memory);
+    free(var);
+    return (status);
+}
diff --git a/backend/escl/escl_tiff.c b/backend/escl/escl_tiff.c
new file mode 100644
index 0000000..52aec20
--- /dev/null
+++ b/backend/escl/escl_tiff.c
@@ -0,0 +1,119 @@
+/* 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.  */
+
+#define DEBUG_DECLARE_ONLY
+#include "../include/sane/config.h"
+
+#include "escl.h"
+
+#include "../include/sane/sanei.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#if(defined HAVE_TIFFIO_H)
+#include <tiffio.h>
+#endif
+
+#include <setjmp.h>
+
+
+#if(defined HAVE_TIFFIO_H)
+
+/**
+ * \fn SANE_Status escl_sane_decompressor(escl_sane_t *handler)
+ * \brief Function that aims to decompress the png image to SANE be able to read the image.
+ *        This function is called in the "sane_read" function.
+ *
+ * \return SANE_STATUS_GOOD (if everything is OK, otherwise, SANE_STATUS_NO_MEM/SANE_STATUS_INVAL)
+ */
+SANE_Status
+get_TIFF_data(capabilities_t *scanner, int *w, int *h, int *components)
+{
+    TIFF* tif = NULL;
+    uint32  width = 0;           /* largeur */
+    uint32  height = 0;          /* hauteur */
+    unsigned char *raster = NULL;         /* données de l'image */
+    int bps = 4;
+    uint32 npixels = 0;
+
+    lseek(fileno(scanner->tmp), 0, SEEK_SET);
+    tif = TIFFFdOpen(fileno(scanner->tmp), "temp", "r");
+    if (!tif) {
+        DBG( 1, "Escl Tiff : Can not open, or not a TIFF file.\n");
+        if (scanner->tmp) {
+           fclose(scanner->tmp);
+           scanner->tmp = NULL;
+        }
+        return (SANE_STATUS_INVAL);
+    }
+
+    TIFFGetField(tif, TIFFTAG_IMAGEWIDTH, &width);
+    TIFFGetField(tif, TIFFTAG_IMAGELENGTH, &height);
+    npixels = width * height;
+    raster = (unsigned char*) malloc(npixels * sizeof (uint32));
+    if (raster != NULL)
+    {
+        DBG( 1, "Escl Tiff : Memory allocation problem.\n");
+        if (scanner->tmp) {
+           fclose(scanner->tmp);
+           scanner->tmp = NULL;
+        }
+        return (SANE_STATUS_INVAL);
+    }
+
+    if (!TIFFReadRGBAImage(tif, width, height, (uint32 *)raster, 0))
+    {
+        DBG( 1, "Escl Tiff : Problem reading image data.\n");
+        if (scanner->tmp) {
+           fclose(scanner->tmp);
+           scanner->tmp = NULL;
+        }
+        return (SANE_STATUS_INVAL);
+    }
+    *w = (int)width;
+    *h = (int)height;
+    *components = bps;
+    // we don't need row pointers anymore
+    scanner->img_data = raster;
+    scanner->img_size = (int)(width * height * bps);
+    scanner->img_read = 0;
+    TIFFClose(tif);
+    fclose(scanner->tmp);
+    scanner->tmp = NULL;
+    return (SANE_STATUS_GOOD);
+}
+#else
+
+SANE_Status
+get_TIFF_data(capabilities_t __sane_unused__ *scanner,
+              int __sane_unused__ *w,
+              int __sane_unused__ *h,
+              int __sane_unused__ *bps)
+{
+    return (SANE_STATUS_INVAL);
+}
+
+#endif