Initial import of sane-backends version 1.0.24-1.2

1 files changed, 1871 insertions, 0 deletions

diff --git a/frontend/tstbackend.c b/frontend/tstbackend.c
new file mode 100644
index 0000000..6dcd940
--- /dev/null
+++ b/frontend/tstbackend.c
@@ -0,0 +1,1871 @@
+/* 
+   tstbackend -- backend test utility
+
+   Uses the SANE library.
+   Copyright (C) 2002 Frank Zago (sane at zago dot net)
+   Copyright (C) 2013 Stéphane Voltz <stef.dev@free.fr> : sane_get_devices test
+
+   This file is part of the SANE package.
+
+   This program 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 2 of the
+   License, or (at your option) any later version.
+
+   This program 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 this program; if not, write to the Free Software
+   Foundation, Inc., 59 Temple Place - Suite 330, Boston,
+   MA 02111-1307, USA.
+*/
+
+#define BUILD 19				/* 2013-03-29 */
+
+#include "../include/sane/config.h"
+
+#include <assert.h>
+#include <getopt.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <stdarg.h>
+#include <time.h>
+
+#include <sys/types.h>
+#include <sys/stat.h>
+
+#include "../include/sane/sane.h"
+#include "../include/sane/sanei.h"
+#include "../include/sane/saneopts.h"
+
+static struct option basic_options[] = {
+	{"device-name", required_argument, NULL, 'd'},
+	{"level", required_argument, NULL, 'l'},
+	{"recursion", required_argument, NULL, 'r'},
+	{"get-devices", required_argument, NULL, 'g'},
+	{"help", 0, NULL, 'h'}
+};
+
+static void
+test_options (SANE_Device * device, int can_do_recursive);
+
+enum message_level {
+	MSG,						/* info message */
+	INF,						/* non-urgent warning */
+	WRN,						/* warning */
+	ERR,						/* error, test can continue */
+	FATAL,						/* error, test can't/mustn't continue */
+	BUG							/* bug in tstbackend */
+};
+
+int message_number_wrn = 0;
+int message_number_err = 0;
+#ifdef HAVE_LONG_LONG
+long long checks_done = 0;
+#else
+/* It may overflow, but it's no big deal. */
+long int checks_done = 0;
+#endif
+
+int test_level;
+int verbose_level;
+
+/* Maybe add that to sane.h */
+#define SANE_OPTION_IS_GETTABLE(cap)	(((cap) & (SANE_CAP_SOFT_DETECT | SANE_CAP_INACTIVE)) == SANE_CAP_SOFT_DETECT)
+
+/*--------------------------------------------------------------------------*/
+
+/* Display the message error statistics. */
+static void display_stats(void)
+{
+#ifdef HAVE_LONG_LONG
+	printf("warnings: %d  error: %d  checks: %lld\n", 
+		   message_number_wrn, message_number_err, checks_done);
+#else
+	printf("warnings: %d  error: %d  checks: %ld\n", 
+		   message_number_wrn, message_number_err, checks_done);
+#endif
+}
+
+/* 
+ * If the condition is false, display a message with some headers
+ * depending on the level.
+ *
+ * Returns the condition.
+ *
+ */
+#ifdef __GNUC__
+static int check(enum message_level, int condition, const char *format, ...) __attribute__ ((format (printf, 3, 4)));
+#endif
+static int check(enum message_level level, int condition, const char *format, ...)
+{
+	char str[1000];
+	va_list args;
+
+	if (level != MSG && level != INF) checks_done ++;
+	
+	if (condition != 0) 
+		return condition;
+
+	va_start(args, format);
+	vsprintf(str, format, args);
+	va_end(args);
+
+	switch(level) {
+	case MSG:
+		printf("          %s\n", str);
+		break;
+	case INF:					/* info */
+		printf("info    : %s\n", str);
+		break;
+	case WRN:					/* warning */
+		printf("warning : %s\n", str);
+		message_number_wrn ++;
+		break;
+	case ERR:					/* error */
+		printf("ERROR   : %s\n", str);
+		message_number_err ++;
+		break;
+	case FATAL:					/* fatal error */
+		printf("FATAL ERROR : %s\n", str);
+		message_number_err ++;
+		break;		
+	case BUG:					/* bug in tstbackend */
+		printf("tstbackend BUG : %s\n", str);
+		break;				
+	}
+
+	if (level == FATAL || level == BUG) {
+		/* Fatal error. Generate a core dump. */
+		display_stats();
+		abort();
+	}
+
+	fflush(stdout);
+
+	return(0);
+}
+
+/*--------------------------------------------------------------------------*/
+
+#define GUARDS_SIZE 4			/* 4 bytes */
+#define GUARD1 ((SANE_Word)0x5abf8ea5)
+#define GUARD2 ((SANE_Word)0xa58ebf5a)
+
+/* Allocate the requested memory plus enough room to store some guard bytes. */
+static void *guards_malloc(size_t size)
+{
+	unsigned char *ptr;
+
+	size += 2*GUARDS_SIZE;
+	ptr = malloc(size);
+
+	assert(ptr);
+
+	ptr += GUARDS_SIZE;
+
+	return(ptr);
+}
+
+/* Free some memory allocated by guards_malloc. */
+static void guards_free(void *ptr)
+{
+	unsigned char *p = ptr;
+
+	p -= GUARDS_SIZE;
+	free(p);
+}
+
+/* Set the guards */
+static void guards_set(void *ptr, size_t size)
+{
+	SANE_Word *p;
+
+	p = (SANE_Word *)(((unsigned char *)ptr) - GUARDS_SIZE);
+	*p = GUARD1;
+
+	p = (SANE_Word *)(((unsigned char *)ptr) + size);
+	*p = GUARD2;
+}
+
+/* Check that the guards have not been tampered with. */
+static void guards_check(void *ptr, size_t size)
+{
+	SANE_Word *p;
+
+	p = (SANE_Word *)(((unsigned char *)ptr) - GUARDS_SIZE);
+	check(FATAL, (*p == GUARD1),
+		  "guard before the block has been tampered");
+
+	p = (SANE_Word *)(((unsigned char *)ptr) + size);
+	check(FATAL, (*p == GUARD2),
+		  "guard after the block has been tampered");
+}
+
+/*--------------------------------------------------------------------------*/
+
+static void 
+test_parameters (SANE_Device * device, SANE_Parameters *params)
+{
+	SANE_Status status;
+	SANE_Parameters p;
+
+	status = sane_get_parameters (device, &p);
+	check(FATAL, (status == SANE_STATUS_GOOD), 
+		  "cannot get the parameters (error %s)", sane_strstatus(status));
+
+	check(FATAL, ((p.format == SANE_FRAME_GRAY) ||
+				  (p.format == SANE_FRAME_RGB) ||
+				  (p.format == SANE_FRAME_RED) ||
+				  (p.format == SANE_FRAME_GREEN) ||
+				  (p.format == SANE_FRAME_BLUE)),
+		  "parameter format is not a known SANE_FRAME_* (%d)", p.format);
+
+	check(FATAL, ((p.last_frame == SANE_FALSE) || 
+				  (p.last_frame == SANE_TRUE)),
+		  "parameter last_frame is neither SANE_FALSE or SANE_TRUE (%d)", p.last_frame);
+
+	check(FATAL, ((p.depth == 1) ||
+				  (p.depth == 8) ||
+				  (p.depth == 16)),
+		  "parameter depth is neither 1, 8 or 16 (%d)", p.depth);
+
+	if (params) {
+		*params = p;
+	}
+}
+
+/* Try to set every option in a word list. */
+static void
+test_options_word_list (SANE_Device * device, int option_num, 
+						const SANE_Option_Descriptor *opt,
+						int can_do_recursive)
+{
+	SANE_Status status;
+	int i;
+	SANE_Int val_int;
+	SANE_Int info;
+
+	check(FATAL, (opt->type == SANE_TYPE_INT || 
+			  opt->type == SANE_TYPE_FIXED),
+		  "type must be SANE_TYPE_INT or SANE_TYPE_FIXED (%d)", opt->type);
+
+	if (!SANE_OPTION_IS_SETTABLE(opt->cap)) return;
+
+	for (i=1; i<opt->constraint.word_list[0]; i++) {
+		
+		info = 0x1010;			/* garbage */
+
+		val_int = opt->constraint.word_list[i];
+		status = sane_control_option (device, option_num, 
+									  SANE_ACTION_SET_VALUE, &val_int, &info);
+		
+		check(FATAL, (status == SANE_STATUS_GOOD),
+			  "cannot set a settable option (status=%s)", sane_strstatus(status));
+
+		check(WRN, ((info & ~(SANE_INFO_RELOAD_OPTIONS | 
+							SANE_INFO_RELOAD_PARAMS)) == 0),
+			  "sane_control_option set an invalid info (%d)", info);
+
+		if ((info & SANE_INFO_RELOAD_OPTIONS) && can_do_recursive) {
+			test_options(device, can_do_recursive-1);
+		}
+		if (info & SANE_INFO_RELOAD_PARAMS) {
+			test_parameters(device, NULL);
+		}
+
+		/* The option might have become inactive or unsettable. Skip it. */
+		if (!SANE_OPTION_IS_ACTIVE(opt->cap) || 
+			!SANE_OPTION_IS_SETTABLE(opt->cap)) 
+			return;
+
+	}
+}
+
+/* Try to set every option in a string list. */
+static void
+test_options_string_list (SANE_Device * device, int option_num, 
+						  const SANE_Option_Descriptor *opt,
+						  int can_do_recursive)
+{
+	SANE_Int info;
+	SANE_Status status;
+	SANE_String val_string;
+	int i;
+
+	check(FATAL, (opt->type == SANE_TYPE_STRING),
+		  "type must be SANE_TYPE_STRING (%d)", opt->type);
+
+	if (!SANE_OPTION_IS_SETTABLE(opt->cap)) return;
+
+	for (i=0; opt->constraint.string_list[i] != NULL; i++) {
+
+		val_string = strdup(opt->constraint.string_list[i]);
+		assert(val_string);
+
+		check(WRN, (strlen(val_string) < (size_t)opt->size),
+			  "string [%s] is longer than the max size (%d)",
+			  val_string, opt->size);
+
+		info = 0xE1000;			/* garbage */
+		status = sane_control_option (device, option_num, 
+									  SANE_ACTION_SET_VALUE, val_string, &info);
+
+		check(FATAL, (status == SANE_STATUS_GOOD),
+			  "cannot set a settable option (status=%s)", sane_strstatus(status));
+
+		check(WRN, ((info & ~(SANE_INFO_RELOAD_OPTIONS | 
+							SANE_INFO_RELOAD_PARAMS)) == 0),
+			  "sane_control_option set an invalid info (%d)", info);
+
+		free(val_string);
+
+		if ((info & SANE_INFO_RELOAD_OPTIONS) && can_do_recursive) {
+			test_options(device, can_do_recursive-1);
+		}
+		if (info & SANE_INFO_RELOAD_PARAMS) {
+			test_parameters(device, NULL);
+		}
+
+		/* The option might have become inactive or unsettable. Skip it. */
+		if (!SANE_OPTION_IS_ACTIVE(opt->cap) || 
+			!SANE_OPTION_IS_SETTABLE(opt->cap)) 
+			return;
+	}
+}
+
+/* Test the consistency of the options. */
+static void
+test_options (SANE_Device * device, int can_do_recursive)
+{
+	SANE_Word info;
+	SANE_Int num_dev_options;
+	SANE_Status status;
+	const SANE_Option_Descriptor *opt;
+	int option_num;
+	void *optval;				/* value for the option */
+	size_t optsize;				/* size of the optval buffer */
+
+	/* 
+	 * Test option 0 
+	 */
+	opt = sane_get_option_descriptor (device, 0);
+	check(FATAL, (opt != NULL),
+		  "cannot get option descriptor for option 0 (it must exist)");
+	check(INF, (opt->cap == SANE_CAP_SOFT_DETECT),
+		  "invalid capabilities for option 0 (%d)", opt->cap);
+	check(ERR, (opt->type == SANE_TYPE_INT),
+		  "option 0 type must be SANE_TYPE_INT");
+
+	/* Get the number of options. */
+	status = sane_control_option (device, 0, SANE_ACTION_GET_VALUE, &num_dev_options, 0);
+	check(FATAL, (status == SANE_STATUS_GOOD),
+		  "cannot get option 0 value");
+
+	/* Try to change the number of options. */
+	status = sane_control_option (device, 0, SANE_ACTION_SET_VALUE,
+								  &num_dev_options, &info);
+	check(WRN, (status != SANE_STATUS_GOOD),
+		  "the option 0 value can be set");
+
+	/* 
+	 * Test all options
+	 */
+	option_num = 0;
+	for (option_num = 0; option_num < num_dev_options; option_num++) {
+
+		/* Get the option descriptor */
+		opt = sane_get_option_descriptor (device, option_num);
+		check(FATAL, (opt != NULL),
+			  "cannot get option descriptor for option %d", option_num);
+		check(WRN, ((opt->cap & ~(SANE_CAP_SOFT_SELECT |
+					SANE_CAP_HARD_SELECT |
+					SANE_CAP_SOFT_DETECT |
+					SANE_CAP_EMULATED |
+					SANE_CAP_AUTOMATIC |
+					SANE_CAP_INACTIVE |
+					SANE_CAP_ADVANCED)) == 0),
+			  "invalid capabilities for option [%d, %s] (%x)", option_num, opt->name, opt->cap);
+		check(WRN, (opt->title != NULL),
+			  "option [%d, %s] must have a title", option_num, opt->name);
+		check(WRN, (opt->desc != NULL),
+			  "option [%d, %s] must have a description", option_num, opt->name);
+
+		if (!SANE_OPTION_IS_ACTIVE (opt->cap)) {
+			/* Option not active. Skip the remaining tests. */
+			continue;
+		}
+
+		if(verbose_level) {
+			printf("checking option ""%s""\n",opt->title);
+		}
+
+		if (opt->type == SANE_TYPE_GROUP) {
+			check(INF, (opt->name == NULL || *opt->name == 0),
+				  "option [%d, %s] has a name", option_num, opt->name);
+			check(ERR, (!SANE_OPTION_IS_SETTABLE (opt->cap)),
+				  "option [%d, %s], group option is settable", option_num, opt->name);
+		} else {
+			if (option_num == 0) {
+				check(ERR, (opt->name != NULL && *opt->name ==0),
+					  "option 0 must have an empty name (ie. \"\")");
+			} else {
+				check(ERR, (opt->name != NULL && *opt->name !=0),
+					  "option %d must have a name", option_num);
+			}
+		}
+
+		/* The option name must contain only "a".."z",
+		   "0".."9" and "-" and must start with "a".."z". */
+		if (opt->name && opt->name[0]) {
+			const char *p = opt->name;
+
+			check(ERR, (*p >= 'a' && *p <= 'z'),
+				  "name for option [%d, %s] must start with in letter in [a..z]",
+				  option_num, opt->name);
+
+			p++;
+
+			while(*p) {
+				check(ERR, ((*p >= 'a' && *p <= 'z') ||
+							(*p == '-') ||
+							(*p >= '0' && *p <= '9')),
+					  "name for option [%d, %s] must only have the letters [-a..z0..9]",
+					  option_num, opt->name);
+				p++;
+			}
+		}
+
+		optval = NULL;
+		optsize = 0;
+
+		switch(opt->type) {
+		case SANE_TYPE_BOOL:
+			check(WRN, (opt->size == sizeof(SANE_Word)),
+				  "size of option %s is incorrect", opt->name);
+			optval = guards_malloc(opt->size);
+			optsize = opt->size;
+			check(WRN, (opt->constraint_type == SANE_CONSTRAINT_NONE),
+				  "invalid constraint type for option [%d, %s] (%d)", option_num, opt->name, opt->constraint_type);
+			break;
+			
+		case SANE_TYPE_INT:
+		case SANE_TYPE_FIXED:
+			check(WRN, (opt->size > 0 && (opt->size % sizeof(SANE_Word) == 0)),
+				  "invalid size for option %s", opt->name);
+			optval = guards_malloc(opt->size);
+			optsize = opt->size;
+			check(WRN, (opt->constraint_type == SANE_CONSTRAINT_NONE ||
+						opt->constraint_type == SANE_CONSTRAINT_RANGE ||
+						opt->constraint_type == SANE_CONSTRAINT_WORD_LIST),
+				  "invalid constraint type for option [%d, %s] (%d)", option_num, opt->name, opt->constraint_type);
+			break;
+
+		case SANE_TYPE_STRING:	
+			check(WRN, (opt->size >= 1),
+				  "size of option [%d, %s] must be at least 1 for the NUL terminator", option_num, opt->name);
+			check(INF, (opt->unit == SANE_UNIT_NONE),
+				  "unit of option [%d, %s] is not SANE_UNIT_NONE", option_num, opt->name);
+			check(WRN, (opt->constraint_type == SANE_CONSTRAINT_STRING_LIST ||
+					  opt->constraint_type == SANE_CONSTRAINT_NONE),
+				  "invalid constraint type for option [%d, %s] (%d)", option_num, opt->name, opt->constraint_type);
+			optval = guards_malloc(opt->size);
+			optsize = opt->size;
+			break;
+
+		case SANE_TYPE_BUTTON:  
+		case SANE_TYPE_GROUP:
+			check(INF, (opt->unit == SANE_UNIT_NONE),
+				  "option [%d, %s], unit is not SANE_UNIT_NONE", option_num, opt->name);
+			check(INF, (opt->size == 0),
+				  "option [%d, %s], size is not 0", option_num, opt->name);
+			check(WRN, (opt->constraint_type == SANE_CONSTRAINT_NONE),
+				  "invalid constraint type for option [%d, %s] (%d)", option_num, opt->name, opt->constraint_type);
+			break;
+
+		default:
+			check(ERR, 0,
+				  "invalid type %d for option %s", 
+				  opt->type, opt->name);
+			break;
+		}
+		
+		if (optval) {
+			/* This is an option with a value */
+
+			/* get with NULL info.
+			 *
+			 * The SANE standard is not explicit on that subject. I
+			 * consider that an inactive option shouldn't be read by a
+			 * frontend because its value is meaningless. I think
+			 * that, in that case, SANE_STATUS_INVAL is an appropriate
+			 * return.  
+			 */
+			guards_set(optval, optsize);
+			status = sane_control_option (device, option_num,
+										  SANE_ACTION_GET_VALUE, optval, NULL);
+			guards_check(optval, optsize);
+
+			if (SANE_OPTION_IS_GETTABLE (opt->cap)) {
+				check(ERR, (status == SANE_STATUS_GOOD),
+					  "cannot get option [%d, %s] value, although it is active (%s)", option_num, opt->name, sane_strstatus(status));
+			} else {
+				check(ERR, (status == SANE_STATUS_INVAL),
+					  "was able to get option [%d, %s] value, although it is not active", option_num, opt->name);
+			}
+
+			/* set with NULL info */
+			guards_set(optval, optsize);
+			status = sane_control_option (device, option_num, 
+										  SANE_ACTION_SET_VALUE, optval, NULL);
+			guards_check(optval, optsize);
+			if (SANE_OPTION_IS_SETTABLE (opt->cap) && SANE_OPTION_IS_ACTIVE (opt->cap)) {
+				check(ERR, (status == SANE_STATUS_GOOD),
+					  "cannot set option [%d, %s] value, although it is active and settable (%s)", option_num, opt->name, sane_strstatus(status));
+			} else {
+				check(ERR, (status == SANE_STATUS_INVAL),
+					  "was able to set option [%d, %s] value, although it is not active or settable", option_num, opt->name);
+			}  
+			
+			/* Get with invalid info. Since if is a get, info should be either
+			 * ignored or set to 0. */
+			info = 0xdeadbeef;
+			guards_set(optval, optsize);
+			status = sane_control_option (device, option_num, SANE_ACTION_GET_VALUE, 
+										  optval, &info);
+			guards_check(optval, optsize);
+			if (SANE_OPTION_IS_GETTABLE (opt->cap)) {
+				check(ERR, (status == SANE_STATUS_GOOD),
+					  "cannot get option [%d, %s] value, although it is active (%s)", option_num, opt->name, sane_strstatus(status));
+			} else {
+				check(ERR, (status == SANE_STATUS_INVAL),
+					  "was able to get option [%d, %s] value, although it is not active", option_num, opt->name);
+			}
+			check(ERR, ((info == (SANE_Int)0xdeadbeef) || (info == 0)),
+				  "when getting option [%d, %s], info was set to %x", option_num, opt->name, info);
+			
+			/* Set with invalid info. Info should be reset by the backend. */
+			info = 0x10000;
+			guards_set(optval, optsize);
+			status = sane_control_option (device, option_num, 
+										  SANE_ACTION_SET_VALUE, optval, &info);
+			guards_check(optval, optsize);
+			if (SANE_OPTION_IS_SETTABLE (opt->cap) && SANE_OPTION_IS_ACTIVE (opt->cap)) {
+				check(ERR, (status == SANE_STATUS_GOOD),
+					  "cannot set option [%d, %s] value, although it is active and settable (%s)", option_num, opt->name, sane_strstatus(status));
+
+				check(ERR, ((info & ~(SANE_INFO_INEXACT | 
+									  SANE_INFO_RELOAD_OPTIONS | 
+									  SANE_INFO_RELOAD_PARAMS)) == 0),
+					  "sane_control_option set some wrong bit in info (%d)", info);
+
+				if (info & SANE_INFO_RELOAD_PARAMS) {
+					test_parameters(device, NULL);
+				}
+			} else {
+				check(ERR, (status == SANE_STATUS_INVAL),
+					  "was able to set option [%d, %s] value, although it is not active or settable", option_num, opt->name);
+			}
+
+			/* Ask the backend to set the option automatically. */
+			guards_set(optval, optsize);
+			status = sane_control_option (device, option_num, 
+										  SANE_ACTION_SET_AUTO, optval, &info);
+			guards_check(optval, optsize);
+			if (SANE_OPTION_IS_SETTABLE (opt->cap) && 
+				SANE_OPTION_IS_ACTIVE (opt->cap) &&
+				(opt->cap & SANE_CAP_AUTOMATIC)) {
+				check(ERR, (status == SANE_STATUS_GOOD),
+					  "cannot set the option [%d, %s] automatically.", option_num, opt->name);
+			} else {
+				check(ERR, (status != SANE_STATUS_GOOD),
+					  "was able to automatically set option [%d, %s], although it is not active or settable or automatically settable", option_num, opt->name);
+			}
+			if (info & SANE_INFO_RELOAD_PARAMS) {
+				test_parameters(device, NULL);
+			}
+		}
+
+		if (optval) {
+			guards_free(optval);
+			optval = NULL; 
+		}
+
+		/* Some capabilities checks. */
+		check(ERR, ((opt->cap & (SANE_CAP_HARD_SELECT | SANE_CAP_SOFT_SELECT)) !=
+					(SANE_CAP_HARD_SELECT | SANE_CAP_SOFT_SELECT)),
+			  "option [%d, %s], SANE_CAP_HARD_SELECT and SANE_CAP_SOFT_SELECT are mutually exclusive", option_num, opt->name);
+		if (opt->cap & SANE_CAP_SOFT_SELECT) {
+			check(ERR, ((opt->cap & SANE_CAP_SOFT_DETECT) != 0),
+				  "option [%d, %s], SANE_CAP_SOFT_DETECT must be set if SANE_CAP_SOFT_SELECT is set", option_num, opt->name);
+		}
+		if ((opt->cap & (SANE_CAP_SOFT_SELECT | 
+						 SANE_CAP_HARD_SELECT | 
+						 SANE_CAP_SOFT_DETECT)) == SANE_CAP_SOFT_DETECT) {
+			check(ERR, (!SANE_OPTION_IS_SETTABLE (opt->cap)),
+				  "option [%d, %s], must not be settable", option_num, opt->name);
+		}
+		
+		if (!SANE_OPTION_IS_SETTABLE (opt->cap)) {
+			/* Unsettable option. Ignore the rest of the test. */
+			continue;
+		}
+	
+		/* Check that will sane_control_option copy the string
+		 * parameter and not just store a pointer to it. */
+		if (opt->type == SANE_TYPE_STRING) {
+			SANE_String val_string2;
+			char *optstr;
+
+			optstr = guards_malloc(opt->size);
+			val_string2 = guards_malloc(opt->size);				
+
+			/* Poison the current value. */
+			strncpy(optstr, "-pOiSoN-", opt->size-1);
+			optstr[opt->size-1] = 0;
+
+			/* Get the value */
+			guards_set(optstr, opt->size);
+			status = sane_control_option (device, option_num, SANE_ACTION_GET_VALUE, 
+										  optstr, NULL);
+			guards_check(optstr, opt->size);
+			check(FATAL, (status == SANE_STATUS_GOOD),
+				  "cannot get option [%d, %s] value", option_num, opt->name);
+			check(FATAL, (strcmp(optstr, "-pOiSoN-") != 0),
+				  "sane_control_option did not set a value");
+
+			/* Set the value */
+			guards_set(optstr, opt->size);
+			status = sane_control_option (device, option_num, 
+										  SANE_ACTION_SET_VALUE, optstr, NULL);
+			guards_check(optstr, opt->size);
+			check(ERR, (status == SANE_STATUS_GOOD),
+				  "cannot set option [%d, %s] value", option_num, opt->name);
+
+			/* Poison the returned value. */
+			strncpy(optstr, "-pOiSoN-", opt->size-1);
+			optstr[opt->size-1] = 0;
+
+			/* Read again the value and compare. */
+			guards_set(val_string2, opt->size);			
+			status = sane_control_option (device, option_num, SANE_ACTION_GET_VALUE, 
+										  val_string2, NULL);
+			guards_check(val_string2, opt->size);
+			check(ERR, (status == SANE_STATUS_GOOD),
+				  "cannot get option [%d, %s] value", option_num, opt->name);
+			
+			check(FATAL, (strcmp(optstr, val_string2) != 0),
+				  "sane_control_option did not copy the string parameter for option [%d, %s]", option_num, opt->name);
+
+			guards_free(optstr);
+			guards_free(val_string2);
+		}
+
+		/* Try both boolean options. */
+		if (opt->type == SANE_TYPE_BOOL) {
+			SANE_Bool org_v;
+			SANE_Bool v;
+			
+			status = sane_control_option (device, option_num, SANE_ACTION_GET_VALUE, 
+										  &org_v, &info);
+			check(ERR, (status == SANE_STATUS_GOOD),
+				  "cannot get boolean option [%d, %s] value (%s)", option_num, opt->name, sane_strstatus(status));
+			/* Invert the condition. */
+			switch(org_v) {
+			case SANE_FALSE:
+				v = SANE_TRUE;
+				break;
+			case SANE_TRUE:
+				v = SANE_FALSE;
+				break;
+			default:
+				check(ERR, 0,
+					  "invalid boolean value %d for option [%d, %s]", 
+					  org_v, option_num, opt->name);
+			}
+			
+			/* Set the opposite of the current value. */
+			status = sane_control_option (device, option_num, 
+										  SANE_ACTION_SET_VALUE, &v, &info);
+			check(ERR, (status == SANE_STATUS_GOOD),
+				  "cannot set boolean option [%d, %s] value (%s)", option_num, opt->name, sane_strstatus(status));
+			check(ERR, (v != org_v),
+				  "boolean values should be different");
+
+			if (info & SANE_INFO_RELOAD_PARAMS) {
+				test_parameters(device, NULL);
+			}
+
+			/* Set the initial value. */
+			v = org_v;
+			status = sane_control_option (device, option_num, 
+										  SANE_ACTION_SET_VALUE, &v, &info);
+			check(ERR, (status == SANE_STATUS_GOOD),
+				  "cannot set boolean option [%d, %s] value (%s)", option_num, opt->name, sane_strstatus(status));
+			check(ERR, (v == org_v),
+				  "boolean values should be the same");
+
+			if (info & SANE_INFO_RELOAD_PARAMS) {
+				test_parameters(device, NULL);
+			}			
+		}
+		
+		/* Try to set an invalid option. */
+		switch(opt->type) {
+		case SANE_TYPE_BOOL: {
+			SANE_Word v;	/* should be SANE_Bool instead */
+				
+			v = -1;				/* invalid value. must be SANE_FALSE or SANE_TRUE */
+			status = sane_control_option (device, option_num, 
+										  SANE_ACTION_SET_VALUE, &v, NULL);
+			check(ERR, (status != SANE_STATUS_GOOD),
+				  "was able to set an invalid value for boolean option [%d, %s]", option_num, opt->name);
+
+			v = 2;				/* invalid value. must be SANE_FALSE or SANE_TRUE */
+			status = sane_control_option (device, option_num, 
+										  SANE_ACTION_SET_VALUE, &v, NULL);
+			check(ERR, (status != SANE_STATUS_GOOD),
+				  "was able to set an invalid value for boolean option [%d, %s]", option_num, opt->name);
+		}
+		break;
+
+		case SANE_TYPE_FIXED:
+		case SANE_TYPE_INT: {
+			SANE_Int *v;
+			unsigned int i;
+
+			v = guards_malloc(opt->size);
+
+			/* I can only think of a test for
+			 * SANE_CONSTRAINT_RANGE. This tests the behaviour of
+			 * sanei_constrain_value(). */
+			if (opt->constraint_type == SANE_CONSTRAINT_RANGE) {
+				for(i=0; i<opt->size / sizeof(SANE_Int); i++)
+					v[i] = opt->constraint.range->min - 1;	/* invalid range */
+
+				guards_set(v, opt->size);
+				status = sane_control_option (device, option_num, 
+											  SANE_ACTION_SET_VALUE, v, &info);
+				guards_check(v, opt->size);
+				check(ERR, (status == SANE_STATUS_GOOD && (info & SANE_INFO_INEXACT) ),
+					  "incorrect return when setting an invalid range value for option [%d, %s] (status %s, info %x)", option_num, opt->name, sane_strstatus(status), info);
+
+				/* Set the corrected value. */
+				guards_set(v, opt->size);
+				status = sane_control_option (device, option_num, 
+											  SANE_ACTION_SET_VALUE, v, &info);
+				guards_check(v, opt->size);
+				check(ERR, (status == SANE_STATUS_GOOD && !(info & SANE_INFO_INEXACT) ),
+					  "incorrect return when setting an invalid range value for option [%d, %s] (status %s, info %x)", option_num, opt->name, sane_strstatus(status), info);
+
+
+				for(i=0; i<opt->size / sizeof(SANE_Int); i++)
+					v[i] = opt->constraint.range->max + 1; /* invalid range */
+
+				guards_set(v, opt->size);
+				status = sane_control_option (device, option_num, 
+											  SANE_ACTION_SET_VALUE, v, &info);
+				guards_check(v, opt->size);
+				check(ERR, (status == SANE_STATUS_GOOD && (info & SANE_INFO_INEXACT) ),
+					  "incorrect return when setting an invalid range value for option [%d, %s] (status %s, info %x)", option_num, opt->name, sane_strstatus(status), info);
+
+				/* Set the corrected value. */
+				guards_set(v, opt->size);
+				status = sane_control_option (device, option_num, 
+											  SANE_ACTION_SET_VALUE, v, &info);
+				guards_check(v, opt->size);
+				check(ERR, (status == SANE_STATUS_GOOD && !(info & SANE_INFO_INEXACT) ),
+					  "incorrect return when setting a valid range value for option [%d, %s] (status %s, info %x)", option_num, opt->name, sane_strstatus(status), info);
+			}
+
+			guards_free(v);
+		}
+		break;
+
+		default:
+			break;
+		}
+		
+		/* TODO: button */
+		
+		/* 
+		 * Here starts all the recursive stuff. After the test, it is
+		 * possible that the value is not settable nor active
+		 * anymore. 
+		 */
+		
+		/* Try to set every option in a list */
+		switch(opt->constraint_type) {
+		case SANE_CONSTRAINT_WORD_LIST:
+			check(FATAL, (opt->constraint.word_list != NULL),
+				  "no constraint list for option [%d, %s]", option_num, opt->name);
+			test_options_word_list (device, option_num, opt, can_do_recursive);
+			break;
+
+		case SANE_CONSTRAINT_STRING_LIST:
+			check(FATAL, (opt->constraint.string_list != NULL),
+				  "no constraint list for option [%d, %s]", option_num, opt->name);
+			test_options_string_list (device, option_num, opt, can_do_recursive);
+			break;
+			
+		case SANE_CONSTRAINT_RANGE:
+			check(FATAL, (opt->constraint.range != NULL),
+				  "no constraint range for option [%d, %s]", option_num, opt->name);
+			check(FATAL, (opt->constraint.range->max >= opt->constraint.range->min),
+				  "incorrect range for option [%d, %s] (min=%d > max=%d)", 
+				  option_num, opt->name, opt->constraint.range->min, opt->constraint.range->max);
+			/* Recurse. */
+			if (can_do_recursive) {
+				test_options(device, can_do_recursive-1);
+			}
+			break;
+
+		case SANE_CONSTRAINT_NONE:
+			check(INF, (opt->constraint.range == NULL),
+				  "option [%d, %s] has some constraint value set", option_num, opt->name);
+
+			/* Recurse. */
+			if (can_do_recursive) {
+				test_options(device, can_do_recursive-1);
+			}
+			break;
+		}
+
+		/* End of the test for that option. */
+	}		
+
+	/* test random non-existing options. */
+	opt = sane_get_option_descriptor (device, -1);
+	check(ERR, (opt == NULL),
+		  "was able to get option descriptor for option -1");
+
+	opt = sane_get_option_descriptor (device, num_dev_options+1);
+	check(ERR, (opt == NULL),
+		  "was able to get option descriptor for option %d", num_dev_options+1);
+
+	opt = sane_get_option_descriptor (device, num_dev_options+2);
+	check(ERR, (opt == NULL),
+		  "was able to get option descriptor for option %d", num_dev_options+2);
+	
+	opt = sane_get_option_descriptor (device, num_dev_options+50);
+	check(ERR, (opt == NULL),
+		  "was able to get option descriptor for option %d", num_dev_options+50);
+}
+
+/* Get an option descriptor by the name of the option. */
+static const SANE_Option_Descriptor *get_optdesc_by_name(SANE_Handle device, const char *name, int *option_num)
+{
+	const SANE_Option_Descriptor *opt;
+	SANE_Int num_dev_options;
+	SANE_Status status;	
+	
+	/* Get the number of options. */
+	status = sane_control_option (device, 0, SANE_ACTION_GET_VALUE, &num_dev_options, 0);
+	check(FATAL, (status == SANE_STATUS_GOOD),
+		  "cannot get option 0 value (%s)", sane_strstatus(status));
+
+	for (*option_num = 0; *option_num < num_dev_options; (*option_num)++) {
+
+		/* Get the option descriptor */
+		opt = sane_get_option_descriptor (device, *option_num);
+		check(FATAL, (opt != NULL),
+			  "cannot get option descriptor for option %d", *option_num);
+	
+		if (opt->name && strcmp(opt->name, name) == 0) {
+			return(opt);
+		}
+	}
+	return(NULL);
+}
+
+/* Set the first value for an option. That equates to the minimum for a
+ * range or the first element in a list. */
+static void set_min_value(SANE_Handle device, int option_num, 
+						  const SANE_Option_Descriptor *opt)
+{
+	SANE_Status status;	
+	SANE_String val_string;
+	SANE_Int val_int;
+	int rc;
+
+	check(BUG, (SANE_OPTION_IS_SETTABLE(opt->cap)),
+		  "option is not settable");
+
+	switch(opt->constraint_type) {
+	case SANE_CONSTRAINT_WORD_LIST:
+		rc = check(ERR, (opt->constraint.word_list[0] > 0),
+				   "no value in the list for option %s", opt->name);
+		if (!rc) return;
+		val_int = opt->constraint.word_list[1];
+		status = sane_control_option (device, option_num,
+									  SANE_ACTION_SET_VALUE, &val_int, NULL);
+		check(ERR, (status == SANE_STATUS_GOOD),
+			  "cannot set option %s to %d (%s)", opt->name, val_int, sane_strstatus(status));
+		break;
+
+	case SANE_CONSTRAINT_STRING_LIST:
+		rc = check(ERR, (opt->constraint.string_list[0] != NULL),
+				   "no value in the list for option %s", opt->name);
+		if (!rc) return;
+		val_string = strdup(opt->constraint.string_list[0]);
+		assert(val_string);
+		status = sane_control_option (device, option_num, 
+									  SANE_ACTION_SET_VALUE, val_string, NULL);
+		check(ERR, (status == SANE_STATUS_GOOD),
+			  "cannot set option %s to [%s] (%s)", opt->name, val_string, sane_strstatus(status));
+		free(val_string);
+		break;
+
+	case SANE_CONSTRAINT_RANGE:
+		val_int = opt->constraint.range->min;
+		status = sane_control_option (device, option_num,
+									  SANE_ACTION_SET_VALUE, &val_int, NULL);
+		check(ERR, (status == SANE_STATUS_GOOD),
+			  "cannot set option %s to %d (%s)", opt->name, val_int, sane_strstatus(status));
+		break;
+		
+	default:
+		abort();
+	}
+}
+
+/* Set the last value for an option. That equates to the maximum for a
+ * range or the last element in a list. */
+static void set_max_value(SANE_Handle device, int option_num, 
+						  const SANE_Option_Descriptor *opt)
+{
+	SANE_Status status;	
+	SANE_String val_string;
+	SANE_Int val_int;
+	int i;
+	int rc;
+
+	check(BUG, (SANE_OPTION_IS_SETTABLE(opt->cap)),
+		  "option is not settable");
+
+	switch(opt->constraint_type) {
+	case SANE_CONSTRAINT_WORD_LIST:
+		rc = check(ERR, (opt->constraint.word_list[0] > 0),
+				   "no value in the list for option %s", opt->name);
+		if (!rc) return;
+		val_int = opt->constraint.word_list[opt->constraint.word_list[0]];
+		status = sane_control_option (device, option_num,
+									  SANE_ACTION_SET_VALUE, &val_int, NULL);
+		check(ERR, (status == SANE_STATUS_GOOD),
+			  "cannot set option %s to %d (%s)", opt->name, val_int, sane_strstatus(status));
+		break;
+
+	case SANE_CONSTRAINT_STRING_LIST:
+		rc = check(ERR, (opt->constraint.string_list[0] != NULL),
+				   "no value in the list for option %s", opt->name);
+		if (!rc) return;
+		for (i=1; opt->constraint.string_list[i] != NULL; i++);
+		val_string = strdup(opt->constraint.string_list[i-1]);
+		assert(val_string);
+		status = sane_control_option (device, option_num, 
+									  SANE_ACTION_SET_VALUE, val_string, NULL);
+		check(ERR, (status == SANE_STATUS_GOOD),
+			  "cannot set option %s to [%s] (%s)", opt->name, val_string, sane_strstatus(status));
+		free(val_string);
+		break;
+
+	case SANE_CONSTRAINT_RANGE:
+		val_int = opt->constraint.range->max;
+		status = sane_control_option (device, option_num,
+									  SANE_ACTION_SET_VALUE, &val_int, NULL);
+		check(ERR, (status == SANE_STATUS_GOOD),
+			  "cannot set option %s to %d (%s)", opt->name, val_int, sane_strstatus(status));
+		break;
+		
+	default:
+		abort();
+	}
+}
+
+/* Set a random value for an option amongst the possible values. */
+static void set_random_value(SANE_Handle device, int option_num, 
+							 const SANE_Option_Descriptor *opt)
+{
+	SANE_Status status;	
+	SANE_String val_string;
+	SANE_Int val_int;
+	int i;
+	int rc;
+
+	check(BUG, (SANE_OPTION_IS_SETTABLE(opt->cap)),
+		  "option is not settable");
+
+	switch(opt->constraint_type) {
+	case SANE_CONSTRAINT_WORD_LIST:
+		rc = check(ERR, (opt->constraint.word_list[0] > 0),
+				   "no value in the list for option %s", opt->name);
+		if (!rc) return;
+		i=1+(rand() % opt->constraint.word_list[0]);
+		val_int = opt->constraint.word_list[i];
+		status = sane_control_option (device, option_num,
+									  SANE_ACTION_SET_VALUE, &val_int, NULL);
+		check(ERR, (status == SANE_STATUS_GOOD),
+			  "cannot set option %s to %d (%s)", opt->name, val_int, sane_strstatus(status));
+		break;
+
+	case SANE_CONSTRAINT_STRING_LIST:
+		rc = check(ERR, (opt->constraint.string_list[0] != NULL),
+				   "no value in the list for option %s", opt->name);
+		if (!rc) return;
+		for (i=0; opt->constraint.string_list[i] != NULL; i++);
+		i = rand() % i;
+		val_string = strdup(opt->constraint.string_list[0]);
+		assert(val_string);
+		status = sane_control_option (device, option_num, 
+									  SANE_ACTION_SET_VALUE, val_string, NULL);
+		check(ERR, (status == SANE_STATUS_GOOD),
+			  "cannot set option %s to [%s] (%s)", opt->name, val_string, sane_strstatus(status));
+		free(val_string);
+		break;
+
+	case SANE_CONSTRAINT_RANGE:
+		i = opt->constraint.range->max - opt->constraint.range->min;
+		i = rand() % i;
+		val_int = opt->constraint.range->min + i;
+		status = sane_control_option (device, option_num,
+									  SANE_ACTION_SET_VALUE, &val_int, NULL);
+		check(ERR, (status == SANE_STATUS_GOOD),
+			  "cannot set option %s to %d (%s)", opt->name, val_int, sane_strstatus(status));
+		break;
+		
+	default:
+		abort();
+	}
+}
+
+/*--------------------------------------------------------------------------*/
+
+/* Returns a string with the value of an option. */
+static char *get_option_value(SANE_Handle device, const char *option_name)
+{
+	const SANE_Option_Descriptor *opt;
+	void *optval;				/* value for the option */
+	int optnum;
+	static char str[100];
+	SANE_Status status;	
+
+	opt = get_optdesc_by_name(device, option_name, &optnum);
+	if (opt) {
+		
+		optval = guards_malloc(opt->size);
+		status = sane_control_option (device, optnum,
+									  SANE_ACTION_GET_VALUE, optval, NULL);
+		
+		if (status == SANE_STATUS_GOOD) {
+			switch(opt->type) {
+				
+			case SANE_TYPE_BOOL:
+				if (*(SANE_Word*) optval == SANE_FALSE) {
+					strcpy(str, "FALSE");
+				} else {
+					strcpy(str, "TRUE");
+				}
+				break;
+			
+			case SANE_TYPE_INT:
+				sprintf(str, "%d", *(SANE_Word*) optval);
+				break;
+				
+			case SANE_TYPE_FIXED: {
+				int i;
+				i = SANE_UNFIX(*(SANE_Word*) optval);
+				sprintf(str, "%d", i);
+			}
+			break;
+				
+			case SANE_TYPE_STRING:
+				strcpy(str, optval);
+				break;
+				
+			default:
+				str[0] = 0;
+			}
+		} else {
+			/* Shouldn't happen. */
+			strcpy(str, "backend default");
+		}
+
+		guards_free(optval);
+
+	} else {
+		/* The option does not exists. */
+		strcpy(str, "backend default");
+	}
+
+	return(str);
+}
+
+/* Display the parameters that used for a scan. */
+static char *display_scan_parameters(SANE_Handle device)
+{
+	static char str[150];
+	char *p = str;
+
+	*p = 0;
+	
+	p += sprintf(p, "scan mode=[%s] ", get_option_value(device, SANE_NAME_SCAN_MODE));
+	p += sprintf(p, "resolution=[%s] ", get_option_value(device, SANE_NAME_SCAN_RESOLUTION));
+
+	p += sprintf(p, "tl_x=[%s] ", get_option_value(device, SANE_NAME_SCAN_TL_X));
+	p += sprintf(p, "tl_y=[%s] ", get_option_value(device, SANE_NAME_SCAN_TL_Y));
+	p += sprintf(p, "br_x=[%s] ", get_option_value(device, SANE_NAME_SCAN_BR_X));
+	p += sprintf(p, "br_y=[%s] ", get_option_value(device, SANE_NAME_SCAN_BR_Y));
+
+	return(str);
+}
+
+/* Do a scan to test the correctness of the backend. */
+static void test_scan(SANE_Handle device)
+{
+	const SANE_Option_Descriptor *opt;
+	SANE_Status status;	
+	int option_num;
+	SANE_Int val_int;
+	unsigned char *image = NULL;
+	SANE_Parameters params;
+	size_t to_read;
+	SANE_Int len;
+	int ask_len;
+	int rc;
+	int fd;
+
+	/* Set the largest scan possible.  
+	 *
+	 * For that test, the corner
+	 * position must exists and be SANE_CONSTRAINT_RANGE (this is not
+	 * a SANE requirement though).
+	 */
+	opt = get_optdesc_by_name(device, SANE_NAME_SCAN_TL_X, &option_num);
+	if (opt) set_min_value(device, option_num, opt);
+
+	opt = get_optdesc_by_name(device, SANE_NAME_SCAN_TL_Y, &option_num);
+	if (opt) set_min_value(device, option_num, opt);
+
+	opt = get_optdesc_by_name(device, SANE_NAME_SCAN_BR_X, &option_num);
+	if (opt) set_max_value(device, option_num, opt);
+
+	opt = get_optdesc_by_name(device, SANE_NAME_SCAN_BR_Y, &option_num);
+	if (opt) set_max_value(device, option_num, opt);
+
+#define IMAGE_SIZE (512 * 1024)
+	image = guards_malloc(IMAGE_SIZE);
+
+	/* Try a read outside of a scan. */
+	status = sane_read (device, image, len, &len);
+	check(ERR, (status != SANE_STATUS_GOOD),
+		  "it is possible to sane_read outside of a scan");
+
+	/* Try to set the I/O mode outside of a scan. */
+	status = sane_set_io_mode (device, SANE_FALSE);
+	check(ERR, (status == SANE_STATUS_INVAL),
+		  "it is possible to sane_set_io_mode outside of a scan");	
+	status = sane_set_io_mode (device, SANE_TRUE);
+	check(ERR, (status == SANE_STATUS_INVAL ||
+				status == SANE_STATUS_UNSUPPORTED),
+		  "it is possible to sane_set_io_mode outside of a scan");	
+
+	/* Test sane_get_select_fd outside of a scan. */
+	status = sane_get_select_fd(device, &fd);
+	check(ERR, (status == SANE_STATUS_INVAL || 
+				status == SANE_STATUS_UNSUPPORTED),
+		  "sane_get_select_fd outside of a scan returned an invalid status (%s)", 
+		  sane_strstatus (status));
+
+	if (test_level > 2) {
+		/* Do a scan, reading byte per byte */
+		check(MSG, 0, "TEST: scan byte per byte - %s", display_scan_parameters(device));
+
+		test_parameters(device, &params);
+		status = sane_start (device);
+		rc = check(ERR, (status == SANE_STATUS_GOOD),
+				   "cannot start the scan (%s)", sane_strstatus (status));
+		if (!rc) goto the_end;
+
+		/* sane_set_io_mode with SANE_FALSE is always supported. */
+		status = sane_set_io_mode (device, SANE_FALSE);
+		check(ERR, (status == SANE_STATUS_GOOD),
+			  "sane_set_io_mode with SANE_FALSE must return SANE_STATUS_GOOD");
+
+		/* test sane_set_io_mode with SANE_TRUE. */	
+		status = sane_set_io_mode (device, SANE_TRUE);
+		check(ERR, (status == SANE_STATUS_GOOD || 
+					status == SANE_STATUS_UNSUPPORTED),
+			  "sane_set_io_mode with SANE_TRUE returned an invalid status (%s)", 
+			  sane_strstatus (status));
+
+		/* Put the backend back into blocking mode. */
+		status = sane_set_io_mode (device, SANE_FALSE);
+		check(ERR, (status == SANE_STATUS_GOOD),
+			  "sane_set_io_mode with SANE_FALSE must return SANE_STATUS_GOOD");
+
+		/* Test sane_get_select_fd */
+		fd = 0x76575;				/* won't exists */
+		status = sane_get_select_fd(device, &fd);
+		check(ERR, (status == SANE_STATUS_GOOD || 
+					status == SANE_STATUS_UNSUPPORTED),
+			  "sane_get_select_fd returned an invalid status (%s)", 
+			  sane_strstatus (status));
+		if (status == SANE_STATUS_GOOD) {
+			check(ERR, (fd != 0x76575),
+				  "sane_get_select_fd didn't set the fd although it should have");
+			check(ERR, (fd >= 0),
+				  "sane_get_select_fd returned an invalid fd");
+		}
+	
+		/* Check that it is not possible to set an option. It is probably
+		 * a requirement stated indirectly in the section 4.4 on code
+		 * flow.  
+		 */
+		status = sane_control_option (device, option_num, 
+									  SANE_ACTION_SET_VALUE, 
+									  &val_int , NULL);
+		check(WRN, (status != SANE_STATUS_GOOD),
+			  "it is possible to set a value during a scan");
+
+		test_parameters(device, &params);
+
+		if (params.bytes_per_line != 0 && params.lines != 0) {
+		
+			to_read = params.bytes_per_line * params.lines;
+			while(SANE_TRUE) {
+				len = 76457645;		/* garbage */
+				guards_set(image, 1);
+				status = sane_read (device, image, 1, &len);
+				guards_check(image, 1);
+
+				if (status == SANE_STATUS_EOF) {
+					/* End of scan */
+					check(ERR, (len == 0),
+						  "the length returned is not 0");
+					break;
+				}
+
+				rc = check(ERR, (status == SANE_STATUS_GOOD),
+						   "scan stopped - status is %s", sane_strstatus (status));
+				if (!rc) {
+					check(ERR, (len == 0),
+						  "the length returned is not 0");
+					break;
+				}
+
+				/* The scanner can only return 1. If it returns 0, we may
+				 * loop forever. */
+				rc = check(ERR, (len == 1),
+						   "backend returned 0 bytes - skipping test");
+				if (!rc) {
+					break;
+				}
+
+				to_read -= len;
+			}
+
+			if (params.lines != -1) {
+				check(ERR, (to_read == 0),
+					  "scan ended, but data was truncated");
+			}
+		}
+
+		sane_cancel(device);
+	}
+
+	/* Try a read outside a scan. */
+	ask_len = 1;
+	guards_set(image, ask_len);
+	status = sane_read (device, image, ask_len, &len);
+	guards_check(image, ask_len);
+	check(ERR, (status != SANE_STATUS_GOOD),
+		  "it is possible to sane_read outside a scan");
+
+
+	/* 
+	 * Do a partial scan 
+	 */
+	check(MSG, 0, "TEST: partial scan - %s", display_scan_parameters(device));
+
+	status = sane_start (device);
+	rc = check(ERR, (status == SANE_STATUS_GOOD),
+			   "cannot start the scan (%s)", sane_strstatus (status));
+	if (!rc) goto the_end;
+
+	test_parameters(device, &params);
+
+	if (params.bytes_per_line != 0 && params.lines != 0) {
+		
+		len = 10;
+
+		guards_set(image, 1);
+		status = sane_read (device, image, 1, &len);
+		guards_check(image, 1);
+
+		check(ERR, (len == 1),
+			  "sane_read() didn't return 1 byte as requested");
+	}
+		
+	sane_cancel(device);
+
+
+	/* 
+	 * Do a scan, reading random length. 
+	 */
+	check(MSG, 0, "TEST: scan random length - %s", display_scan_parameters(device));
+
+	test_parameters(device, &params);
+
+	/* Try a read outside a scan. */
+	ask_len = 20;
+	guards_set(image, ask_len);
+	status = sane_read (device, image, ask_len, &len);
+	guards_check(image, ask_len);
+	check(ERR, (status != SANE_STATUS_GOOD),
+		  "it is possible to sane_read outside a scan");
+
+	status = sane_start (device);
+	rc = check(ERR, (status == SANE_STATUS_GOOD),
+			   "cannot start the scan (%s)", sane_strstatus (status));
+	if (!rc) goto the_end;
+
+	/* Check that it is not possible to set an option. */
+	status = sane_control_option (device, option_num, 
+								  SANE_ACTION_SET_VALUE, 
+								  &val_int , NULL);
+	check(WRN, (status != SANE_STATUS_GOOD),
+		  "it is possible to set a value during a scan");
+
+	test_parameters(device, &params);
+
+	if (params.bytes_per_line != 0 && params.lines != 0) {
+		
+		to_read = params.bytes_per_line * params.lines;
+		srandom(time(NULL));
+		
+		while (SANE_TRUE) {
+
+			ask_len = rand() & 0x7ffff;	/* 0 to 512K-1 */
+			if (ask_len == 0) len = 1;
+			len = ask_len + 4978; /* garbage */
+
+			guards_set(image, ask_len);
+			status = sane_read (device, image, ask_len, &len);
+			guards_check(image, ask_len);
+
+			if (status == SANE_STATUS_EOF) {
+				/* End of scan */
+				check(ERR, (len == 0),
+					  "the length returned is not 0");
+				break;
+			}
+
+			rc = check(ERR, (status == SANE_STATUS_GOOD),
+					   "scan stopped - status is %s", sane_strstatus (status));
+			if (!rc) {
+				check(ERR, (len == 0),
+					  "the length returned is not 0");
+				break;
+			}
+
+			/* The scanner cannot return 0. If it returns 0, we may
+			 * loop forever. */
+			rc = check(ERR, (len > 0),
+					   "backend didn't return any data - skipping test");
+			if (!rc) {
+				break;
+			}
+			rc = check(ERR, (len <= ask_len),
+					   "backend returned too much data (%d / %d) - skipping test",
+					   len, ask_len);
+			if (!rc) {
+				break;
+			}
+			
+			to_read -= len;
+		}
+
+		if (params.lines != -1) {
+			check(ERR, (to_read == 0),
+				  "scan ended, but data was truncated");
+		}
+	}
+
+	sane_cancel(device);
+
+	/* Try a read outside a scan. */
+	ask_len = 30;
+	guards_set(image, ask_len);
+	status = sane_read (device, image, ask_len, &len);
+	guards_check(image, ask_len);
+	check(ERR, (status != SANE_STATUS_GOOD),
+		  "it is possible to sane_read outside a scan");
+
+	/*
+	 * Do a scan with a fixed size and a big buffer
+	 */
+	check(MSG, 0, "TEST: scan with a big max_len - %s", display_scan_parameters(device));
+
+	test_parameters(device, &params);
+
+	status = sane_start (device);
+	rc = check(ERR, (status == SANE_STATUS_GOOD),
+			   "cannot start the scan (%s)", sane_strstatus (status));
+	if (!rc) goto the_end;
+
+	test_parameters(device, &params);
+
+	if (params.bytes_per_line != 0 && params.lines != 0) {
+		
+		to_read = params.bytes_per_line * params.lines;
+		while(SANE_TRUE) {
+			ask_len = IMAGE_SIZE;
+			len = rand();		/* garbage */
+
+			guards_set(image, ask_len);
+			status = sane_read (device, image, ask_len, &len);
+			guards_check(image, ask_len);
+
+			if (status == SANE_STATUS_EOF) {
+				/* End of scan */
+				check(ERR, (len == 0),
+					  "the length returned is not 0");
+				break;
+			}
+
+			rc = check(ERR, (status == SANE_STATUS_GOOD),
+					   "scan stopped - status is %s", sane_strstatus (status));
+			if (!rc) {
+				check(ERR, (len == 0),
+					  "the length returned is not 0");
+				break;
+			}
+
+			/* If the scanner return 0, we may loop forever. */
+			rc = check(ERR, (len > 0),
+					   "backend didn't return any data - skipping test");
+			if (!rc) {
+				break;
+			}
+
+			rc = check(ERR, (len <= ask_len),
+					   "backend returned too much data (%d / %d) - skipping test",
+					   len, ask_len);
+			if (!rc) {
+				break;
+			}
+
+			to_read -= len;
+		}
+
+		if (params.lines != -1) {
+			check(ERR, (to_read == 0),
+				  "scan ended, but data was truncated");
+		}
+	}
+
+	sane_cancel(device);
+
+ the_end:
+	if (image) guards_free(image);
+}
+
+/* Do several scans at different scan mode and resolution. */
+static void test_scans(SANE_Device * device)
+{
+	const SANE_Option_Descriptor *scan_mode_opt;
+	const SANE_Option_Descriptor *resolution_mode_opt;
+	SANE_Status status;	
+	int scan_mode_optnum;
+	int resolution_mode_optnum;
+	SANE_String val_string;
+	int i;
+	int rc;
+
+	/* For that test, the requirements are:
+	 *   SANE_NAME_SCAN_MODE exists and is a SANE_CONSTRAINT_STRING_LIST
+	 *   SANE_NAME_SCAN_RESOLUTION exists and is either a SANE_CONSTRAINT_WORD_LIST or a SANE_CONSTRAINT_RANGE.
+	 *
+	 * These are not a SANE requirement, though.
+	 */
+
+	scan_mode_opt = get_optdesc_by_name(device, SANE_NAME_SCAN_MODE, &scan_mode_optnum);
+	if (scan_mode_opt) {
+
+		rc = check(INF, (scan_mode_opt->type == SANE_TYPE_STRING),
+				   "option [%s] is not a SANE_TYPE_STRING - skipping test", SANE_NAME_SCAN_MODE);
+		if (!rc) return;
+		rc = check(INF, (scan_mode_opt->constraint_type == SANE_CONSTRAINT_STRING_LIST),
+				   "constraint for option [%s] is not SANE_CONSTRAINT_STRING_LIST - skipping test", SANE_NAME_SCAN_MODE);
+		if (!rc) return;
+		rc = check(INF, (SANE_OPTION_IS_SETTABLE(scan_mode_opt->cap)),
+				   "option [%s] is not settable - skipping test", SANE_NAME_SCAN_MODE);
+		if (!rc) return;
+	}
+
+	resolution_mode_opt = get_optdesc_by_name(device, SANE_NAME_SCAN_RESOLUTION, &resolution_mode_optnum);
+	if (resolution_mode_opt) {
+		rc = check(INF, (SANE_OPTION_IS_SETTABLE(resolution_mode_opt->cap)),
+				   "option [%s] is not settable - skipping test", SANE_NAME_SCAN_RESOLUTION);
+		if (!rc) return;
+	}
+
+	if (scan_mode_opt) {
+		/* Do several scans, with several resolution. */
+		for (i=0; scan_mode_opt->constraint.string_list[i] != NULL; i++) {
+		
+			val_string = strdup(scan_mode_opt->constraint.string_list[i]);
+			assert(val_string);
+		
+			status = sane_control_option (device, scan_mode_optnum, 
+										  SANE_ACTION_SET_VALUE, val_string, NULL);
+			check(FATAL, (status == SANE_STATUS_GOOD),
+				  "cannot set a settable option (status=%s)", sane_strstatus(status));
+		
+			free(val_string);
+
+			if (resolution_mode_opt) {
+				set_min_value(device, resolution_mode_optnum, 
+							  resolution_mode_opt);			
+				test_scan(device);
+
+				set_max_value(device, resolution_mode_optnum, 
+							  resolution_mode_opt);
+				test_scan(device);
+
+				set_random_value(device, resolution_mode_optnum, 
+								 resolution_mode_opt);
+				test_scan(device);
+			} else {
+				test_scan(device);
+			}
+		}
+	} else {
+		if (resolution_mode_opt) {
+			set_min_value(device, resolution_mode_optnum, 
+						  resolution_mode_opt);			
+			test_scan(device);
+
+			set_max_value(device, resolution_mode_optnum, 
+						  resolution_mode_opt);
+			test_scan(device);
+
+			set_random_value(device, resolution_mode_optnum, 
+							 resolution_mode_opt);
+			test_scan(device);
+		} else {
+			test_scan(device);
+		}
+	}
+}
+
+/** test sane_get_devices
+ * test sane_get_device function, if time is greter than 0,
+ * loop to let tester plug/unplug device to check for correct
+ * hotplug detection
+ * @param device_list device list to fill
+ * @param time time to loop
+ * @return 0 on success
+ */
+static int test_get_devices(const SANE_Device ***device_list, int time)
+{
+int loop=0;
+int i;
+const SANE_Device *dev;
+SANE_Status status;
+
+	status = sane_get_devices (device_list, SANE_TRUE);
+	check(FATAL, (status == SANE_STATUS_GOOD),
+		  "sane_get_devices() failed (%s)", sane_strstatus (status));
+
+	/* Verify that the SANE doc (or tstbackend) is up to date */
+	for (i=0; (*device_list)[i] != NULL; i++) {
+
+		dev = (*device_list)[i];
+
+		check(FATAL, (dev->name != NULL), "device name is NULL");
+		check(FATAL, (dev->vendor != NULL), "device vendor is NULL");
+		check(FATAL, (dev->type != NULL), "device type is NULL");
+		check(FATAL, (dev->model != NULL), "device model is NULL");
+		
+		check(INF, ((strcmp(dev->type, "flatbed scanner") == 0) ||
+					(strcmp(dev->type, "frame grabber") == 0) ||
+					(strcmp(dev->type, "handheld scanner") == 0) ||
+					(strcmp(dev->type, "still camera") == 0) ||
+					(strcmp(dev->type, "video camera") == 0) ||
+					(strcmp(dev->type, "virtual device") == 0) ||
+					(strcmp(dev->type, "film scanner") == 0) ||
+					(strcmp(dev->type, "multi-function peripheral") == 0) ||
+					(strcmp(dev->type, "sheetfed scanner") == 0)),
+					"unknown device type [%s]. Update SANE doc section \"Type Strings\"", dev->type);
+
+		check(INF, (
+					(strcmp(dev->vendor, "AGFA") == 0) ||
+					(strcmp(dev->vendor, "Abaton") == 0) ||
+					(strcmp(dev->vendor, "Acer") == 0) ||
+					(strcmp(dev->vendor, "Apple") == 0) ||
+					(strcmp(dev->vendor, "Artec") == 0) ||
+					(strcmp(dev->vendor, "Avision") == 0) ||
+					(strcmp(dev->vendor, "CANON") == 0) ||
+					(strcmp(dev->vendor, "Connectix") == 0) ||
+					(strcmp(dev->vendor, "Epson") == 0) ||
+					(strcmp(dev->vendor, "Fujitsu") == 0) ||
+					(strcmp(dev->vendor, "Gphoto2") == 0) ||
+					(strcmp(dev->vendor, "Hewlett-Packard") == 0) ||
+					(strcmp(dev->vendor, "IBM") == 0) ||
+					(strcmp(dev->vendor, "Kodak") == 0) ||
+                                        (strcmp(dev->vendor, "Lexmark") == 0) ||
+					(strcmp(dev->vendor, "Logitech") == 0) ||
+					(strcmp(dev->vendor, "Microtek") == 0) ||
+					(strcmp(dev->vendor, "Minolta") == 0) ||
+					(strcmp(dev->vendor, "Mitsubishi") == 0) ||
+					(strcmp(dev->vendor, "Mustek") == 0) ||
+					(strcmp(dev->vendor, "NEC") == 0) ||
+					(strcmp(dev->vendor, "Nikon") == 0) ||
+					(strcmp(dev->vendor, "Noname") == 0) ||
+					(strcmp(dev->vendor, "Plustek") == 0) ||
+					(strcmp(dev->vendor, "Polaroid") == 0) ||
+					(strcmp(dev->vendor, "Relisys") == 0) ||
+					(strcmp(dev->vendor, "Ricoh") == 0) ||
+					(strcmp(dev->vendor, "Sharp") == 0) ||
+					(strcmp(dev->vendor, "Siemens") == 0) ||
+					(strcmp(dev->vendor, "Tamarack") == 0) ||
+					(strcmp(dev->vendor, "UMAX") == 0)),
+			  "unknown device vendor [%s]. Update SANE doc section \"Vendor Strings\"", dev->vendor);
+	}
+
+	/* loop on detecting device to let time to plug/unplug scanners */
+	while(loop<time) {
+		/* print and free detected device list */
+		check(MSG, 0, "DETECTED DEVICES:");
+		for (i=0; (*device_list)[i] != NULL; i++) {
+			dev = (*device_list)[i];
+			check(MSG, 0, "\t%s:%s %s:%s", dev->vendor, dev->name, dev->type, dev->model);
+		}
+		if(i==0) {
+			check(MSG, 0, "\tnone...");
+		}
+		sleep(1);
+		(*device_list) = NULL;
+		status = sane_get_devices (device_list, SANE_TRUE);
+		check(FATAL, (status == SANE_STATUS_GOOD),
+		  "sane_get_devices() failed (%s)", sane_strstatus (status));
+		loop++;
+	}
+	return 0;
+}
+
+static void usage(const char *execname)
+{
+	printf("Usage: %s [-d backend_name] [-l test_level] [-r recursion_level] [-g time (s)]\n", execname);
+	printf("\t-v\tverbose level\n");
+	printf("\t-d\tbackend name\n");
+	printf("\t-l\tlevel of testing (0=some, 1=0+options, 2=1+scans, 3=longest tests)\n");
+	printf("\t-r\trecursion level for option testing (the higher, the longer)\n");
+	printf("\t-g\ttime to loop on sane_get_devices function to test scannet hotplug detection (time is in seconds).\n");
+}
+
+int
+main (int argc, char **argv)
+{
+	char *devname = NULL;
+	SANE_Status status;
+	SANE_Int version_code;
+	SANE_Handle device;
+	int ch;
+	int index;
+	int i;
+	const SANE_Device **device_list;
+	int rc;
+	int recursion_level;
+	int time;
+
+	printf("tstbackend, Copyright (C) 2002 Frank Zago\n");
+	printf("tstbackend comes with ABSOLUTELY NO WARRANTY\n");
+	printf("This is free software, and you are welcome to redistribute it\n");
+	printf("under certain conditions. See COPYING file for details\n\n");
+	printf("This is tstbackend build %d\n\n", BUILD);
+
+	/* Read the command line options. */
+	opterr = 0;
+	recursion_level = 5;		/* 5 levels or recursion should be enough */
+	test_level = 0;			/* basic tests only */
+	time = 0;			/* no get devices loop */
+
+	while ((ch = getopt_long (argc, argv, "-v:d:l:r:g:h", basic_options,
+							  &index)) != EOF) {
+		switch(ch) {
+		case 'v':
+			verbose_level = atoi(optarg);
+			break;
+
+		case 'd':
+			devname = strdup(optarg);
+			break;
+
+		case 'l':
+			test_level = atoi(optarg);
+			if (test_level < 0 || test_level > 4) {
+				fprintf(stderr, "invalid test_level\n");
+				return(1);
+			}
+			break;
+
+		case 'r':
+			recursion_level = atoi(optarg);
+			break;
+
+		case 'g':
+			time = atoi(optarg);
+			break;
+
+		case 'h':
+			usage(argv[0]);
+			return(0);
+
+		case '?':
+			fprintf(stderr, "invalid option\n");
+			return(1);
+
+		default:
+			fprintf(stderr, "bug in tstbackend\n");
+			return(1);
+		}
+	}
+
+	/* First test */
+	check(MSG, 0, "TEST: init/exit");
+	for (i=0; i<10; i++) {
+		/* Test 1. init/exit with a version code */
+		status = sane_init(&version_code, NULL);
+		check(FATAL, (status == SANE_STATUS_GOOD),
+			  "sane_init failed with %s", sane_strstatus (status));
+		check(FATAL, (SANE_VERSION_MAJOR(version_code) == 1),
+			  "invalid SANE version linked");
+		sane_exit();
+
+		/* Test 2. init/exit without a version code */
+		status = sane_init(NULL, NULL);
+		check(FATAL, (status == SANE_STATUS_GOOD),
+			  "sane_init failed with %s", sane_strstatus (status));
+		sane_exit();
+
+		/* Test 3. Init/get_devices/open invalid/exit */
+		status = sane_init(NULL, NULL);
+		check(FATAL, (status == SANE_STATUS_GOOD),
+			  "sane_init failed with %s", sane_strstatus (status));
+
+		status = sane_get_devices (&device_list, SANE_TRUE);
+		check(FATAL, (status == SANE_STATUS_GOOD),
+			  "sane_get_devices() failed (%s)", sane_strstatus (status));
+
+		status = sane_open ("opihndvses75bvt6fg", &device);
+		check(WRN, (status == SANE_STATUS_INVAL),
+			  "sane_open() failed (%s)", sane_strstatus (status));
+		
+		if (status == SANE_STATUS_GOOD)
+			sane_close(device);
+
+		sane_exit();
+
+		/* Test 4. Init/get_devices/open default/exit */
+		status = sane_init(NULL, NULL);
+		check(FATAL, (status == SANE_STATUS_GOOD),
+			  "sane_init failed with %s", sane_strstatus (status));
+
+		status = sane_get_devices (&device_list, SANE_TRUE);
+		check(FATAL, (status == SANE_STATUS_GOOD),
+			  "sane_get_devices() failed (%s)", sane_strstatus (status));
+
+		status = sane_open ("", &device);
+		if (status == SANE_STATUS_GOOD)
+			sane_close(device);
+
+		sane_exit();
+	}
+
+	status = sane_init (&version_code, NULL);
+	check(FATAL, (status == SANE_STATUS_GOOD),
+		  "sane_init failed with %s", sane_strstatus (status));
+  
+	/* Check the device list */
+	rc = test_get_devices(&device_list, time);
+	if (rc) goto the_exit;
+
+	if (!devname) {
+		/* If no device name was specified explicitly, we look at the
+		   environment variable SANE_DEFAULT_DEVICE.  If this variable
+		   is not set, we open the first device we find (if any): */
+		devname = getenv ("SANE_DEFAULT_DEVICE");
+		if (devname) devname = strdup(devname);
+	}
+
+	if (!devname) {
+		if (device_list[0]) {
+			devname = strdup(device_list[0]->name);
+		}
+	}
+
+	rc = check(ERR, (devname != NULL),
+			   "no SANE devices found");
+	if (!rc) goto the_exit;
+
+	check(MSG, 0, "using device %s", devname);
+	
+	/* Test open close */
+	check(MSG, 0, "TEST: open/close");
+	for (i=0; i<10; i++) {
+		status = sane_open (devname, &device);
+		rc = check(ERR, (status == SANE_STATUS_GOOD),
+				   "sane_open failed with %s for device %s", sane_strstatus (status), devname);
+		if (!rc) goto the_exit;
+		sane_close (device);
+	}
+
+	if (test_level < 1) {
+		sane_exit();
+		goto the_exit;
+	}
+
+
+	/* Test options */
+	check(MSG, 0, "TEST: options consistency");
+	status = sane_open (devname, &device);
+	check(FATAL, (status == SANE_STATUS_GOOD),
+		  "sane_open failed with %s for device %s", sane_strstatus (status), devname);
+
+	test_parameters(device, NULL);
+	test_options(device, recursion_level);
+	sane_close (device);
+	sane_exit();
+
+	if (test_level < 2) {
+		goto the_exit;
+	}
+
+
+	/* Test scans */
+	check(MSG, 0, "TEST: scan test");
+	status = sane_init (&version_code, NULL);
+	check(FATAL, (status == SANE_STATUS_GOOD),
+		  "sane_init failed with %s", sane_strstatus (status));
+	status = sane_open (devname, &device);
+	check(FATAL, (status == SANE_STATUS_GOOD),
+		  "sane_open failed with %s for device %s", sane_strstatus (status), devname);
+	test_scans(device);
+	sane_close (device);
+	sane_exit();
+
+ the_exit:
+	if (devname) free(devname);
+	display_stats();
+	return(0);
+}
+
+
+