Support specifying VID/PID for scanning + steamline scanning in tools

CMakeLists.txt

@@ -130,6 +130,7 @@ include(CheckSymbolExists)
 check_symbol_exists(strdup "string.h" HAS_STRDUP)
 check_symbol_exists(strndup "string.h" HAS_STRNDUP)
 check_symbol_exists(strerror_r "string.h" HAS_STRERROR_R)
+check_symbol_exists(strtok_r "string.h" HAS_STRTOK_R)
 check_symbol_exists(newlocale "locale.h" HAS_NEWLOCALE)
 
 option(ENABLE_IPV6 "Define if you want to enable IPv6 support" ON)

iio-config.h.cmakein

@@ -28,6 +28,7 @@
 #cmakedefine HAS_PIPE2
 #cmakedefine HAS_STRDUP
 #cmakedefine HAS_STRNDUP
+#cmakedefine HAS_STRTOK_R
 #cmakedefine HAS_STRERROR_R
 #cmakedefine HAS_NEWLOCALE
 #cmakedefine HAS_PTHREAD_SETNAME_NP

iio-private.h

@@ -249,7 +249,7 @@ struct iio_context * serial_create_context_from_uri(const char *uri);
 
 int local_context_scan(struct iio_scan_result *scan_result);
 
-int usb_context_scan(struct iio_scan_result *scan_result);
+int usb_context_scan(struct iio_scan_result *scan_result, const char *args);
 
 int dnssd_context_scan(struct iio_scan_result *scan_result);
 
@@ -260,6 +260,8 @@ void iio_channel_init_finalize(struct iio_channel *chn);
 unsigned int find_channel_modifier(const char *s, size_t *len_p);
 
 char *iio_strdup(const char *str);
+char *iio_strndup(const char *str, size_t n);
+char *iio_strtok_r(char *str, const char *delim, char **saveptr);
 size_t iio_strlcpy(char * __restrict dst, const char * __restrict src, size_t dsize);
 char * iio_getenv (char * envvar);
 

iio.h

@@ -236,13 +236,22 @@ enum iio_event_direction {
 
 
 /** @brief Create a scan context
- * @param backend A NULL-terminated string containing the backend(s) to use for
- * scanning (example: pre version 0.20 :  "local", "ip", or "usb"; post version
- * 0.20 can handle multiple, including "local:usb:", "ip:usb:", "local:usb:ip:").
- * If NULL, all the available backends are used.
+ * @param backend A NULL-terminated string containing a comma-separated
+ * list of the backend(s) to use for scanning.
  * @param flags Unused for now. Set to 0.
  * @return on success, a pointer to a iio_scan_context structure
- * @return On failure, NULL is returned and errno is set appropriately */
+ * @return On failure, NULL is returned and errno is set appropriately
+ *
+ * <b>NOTE:</b> Libiio version 0.20 and above can handle multiple
+ * strings, for instance "local:usb:", "ip:usb:", "local:usb:ip:", and
+ * require a colon as the delimiter.
+ * Libiio version 0.24 and above prefer a comma instead of colon as the
+ * delimiter, and handle specifying backend-specific information. For
+ * instance, "local,usb=0456:*" will scan the local backend and limit
+ * scans on USB to vendor ID 0x0456, and accept all product IDs. The
+ * "usb=0456:b673" string would limit the scan to the device with this
+ * particular VID/PID. Both IDs are expected in hexadecimal, no 0x
+ * prefix needed. */
 __api __check_ret struct iio_scan_context * iio_create_scan_context(
 		const char *backend, unsigned int flags);
 

libiio.rules.cmakein

@@ -1 +1 @@
-SUBSYSTEM=="usb", PROGRAM=="/bin/sh -c '@CMAKE_INSTALL_FULL_BINDIR@/iio_info -S usb | grep %s{idVendor}:%s{idProduct}'", RESULT!="", MODE="666"
+SUBSYSTEM=="usb", PROGRAM=="/bin/sh -c '@CMAKE_INSTALL_FULL_BINDIR@/iio_info -S usb=%s{idVendor}:%s{idProduct} | grep %s{idVendor}:%s{idProduct}'", RESULT!="", MODE="666"

man/iio_attr.1.in

@@ -83,8 +83,11 @@ Read and Write IIO Context attributes
 .B \-D \-\-debug-attr
 Read and Write IIO Debug attributes
 .TP
-.B \-S, \-\-Scan
-Scan for available IIO contexts, optional arg of specific backend(s) 'ip', 'usb' or 'ip:usb'. If no argument is given, it checks all that are availble.
+.B \-S, \-\-scan
+Scan for available IIO contexts, optional arg of specific backend(s) 'ip', 'usb' or 'ip,usb'.
+Specific options for USB include Vendor ID, Product ID to limit scanning to specific devices 'usb=0456:b673'.
+vid,pid are hexadecimal numbers (no prefix needed), "*" (match any for pid only)
+If no argument is given, it checks all that are availble.
 .TP
 .B \-h, \-\-help
 Tells

man/iio_info.1.in

@@ -79,7 +79,10 @@ with no address part
 .RE
 .TP
 .B \-S, \-\-scan
-Scan for available backends
+Scan for available IIO contexts, optional arg of specific backend(s) 'ip', 'usb' or 'ip,usb'.
+Specific options for USB include Vendor ID, Product ID to limit scanning to specific devices 'usb=0456:b673'.
+vid,pid are hexadecimal numbers (no prefix needed), "*" (match any for pid only)
+If no argument is given, it checks all that are availble.
 .TP
 .B \-a, \-\-auto
 Scan for available contexts and if only one is available use it.

man/iio_readdev.1.in

@@ -76,7 +76,12 @@ Buffer timeout in milliseconds. 0 = no timeout. Default is 0.
 .TP
 .B \-a, \-\-auto
 Scan for available contexts and if only one is available use it.
-
+.TP
+.B \-S, \-\-scan
+Scan for available IIO contexts, optional arg of specific backend(s) 'ip', 'usb' or 'ip,usb'.
+Specific options for USB include Vendor ID, Product ID to limit scanning to specific devices 'usb=0456:b673'.
+vid,pid are hexadecimal numbers (no prefix needed), "*" (match any for pid only)
+If no argument is given, it checks all that are availble.
 .SH RETURN VALUE
 If the specified device is not found, a non-zero exit code is returned.
 

man/iio_writedev.1.in

@@ -60,6 +60,12 @@ normally returned from
 .IP serial:[port]
 .IP local
 with no address part
+.TP
+.B \-S, \-\-scan
+Scan for available IIO contexts, optional arg of specific backend(s) 'ip', 'usb' or 'ip,usb'.
+Specific options for USB include Vendor ID, Product ID to limit scanning to specific devices 'usb=0456:b673'.
+vid,pid are hexadecimal numbers (no prefix needed), "*" (match any for pid only)
+If no argument is given, it checks all that are availble.
 .RE
 .TP
 .B \-t \-\-trigger

scan.c

@@ -8,15 +8,14 @@
 
 #include "iio-config.h"
 #include "iio-private.h"
+#include "sort.h"
 
 #include <errno.h>
 #include <stdbool.h>
 #include <string.h>
 
 struct iio_scan_context {
-	bool scan_usb;
-	bool scan_network;
-	bool scan_local;
+	char *backendopts;
 };
 
 const char * iio_context_info_get_description(
@@ -35,52 +34,80 @@ ssize_t iio_scan_context_get_info_list(struct iio_scan_context *ctx,
 		struct iio_context_info ***info)
 {
 	struct iio_scan_result scan_result = { 0, NULL };
-
-	if (WITH_LOCAL_BACKEND && ctx->scan_local) {
-		int ret = local_context_scan(&scan_result);
-		if (ret < 0) {
-			if (scan_result.info)
-				iio_context_info_list_free(scan_result.info);
-			return ret;
+	struct iio_context_info *out;
+	char *token, *rest=NULL;
+	size_t i, j = 0;
+	ssize_t ret;
+
+	for (token = iio_strtok_r(ctx->backendopts, ",", &rest);
+			token; token = iio_strtok_r(NULL, ",", &rest)) {
+
+		/* Since tokens are all null terminated, it's safe to use strcmp on them */
+		if (WITH_LOCAL_BACKEND && !strcmp(token, "local")) {
+			ret = local_context_scan(&scan_result);
+		} else if (WITH_USB_BACKEND && (!strcmp(token, "usb") ||
+						!strncmp(token, "usb=", sizeof("usb=") - 1))) {
+			token = token[3] == '=' ? token + 4 : NULL;
+			ret = usb_context_scan(&scan_result, token);
+		} else if (HAVE_DNS_SD && !strcmp(token, "ip")) {
+			ret = dnssd_context_scan(&scan_result);
+		} else {
+			ret = -ENODEV;
 		}
+		if (ret < 0)
+			goto err_free_scan_result_info;
 	}
 
-	if (WITH_USB_BACKEND && ctx->scan_usb) {
-		int ret = usb_context_scan(&scan_result);
-		if (ret < 0) {
-			if (scan_result.info)
-				iio_context_info_list_free(scan_result.info);
-			return ret;
-		}
-	}
+	*info = scan_result.info;
 
-	if (HAVE_DNS_SD && ctx->scan_network) {
-		int ret = dnssd_context_scan(&scan_result);
-		if (ret < 0) {
-			if (scan_result.info)
-				iio_context_info_list_free(scan_result.info);
-			return ret;
+	if (scan_result.size > 1) {
+		qsort(scan_result.info, scan_result.size,
+		      sizeof(struct iio_context_info *),
+		      iio_context_info_compare);
+
+		/* there might be duplicates */
+		for (i = 1; i < scan_result.size; i++) {
+			/* ipv6 and ipv4 can have the same uri, but have different descriptions,
+			 * so check both if necessary
+			 */
+			if ((!strcmp(scan_result.info[i - 1]->uri,
+				     scan_result.info[i]->uri)) &&
+			    (!strcmp(scan_result.info[i - 1]->description,
+				     scan_result.info[i]->description))) {
+				out = scan_result.info[i - 1];
+				j++;
+				free(out->description);
+				free(out->uri);
+				out->description = NULL;
+				out->uri = NULL;
+			}
+		}
+		if (j) {
+			/* Force all the nulls to the end */
+			qsort(scan_result.info, scan_result.size,
+					sizeof(struct iio_context_info *),
+					iio_context_info_compare);
+			return (ssize_t) scan_result.size - j;
 		}
 	}
 
-	*info = scan_result.info;
 
 	return (ssize_t) scan_result.size;
+
+err_free_scan_result_info:
+	if (scan_result.info)
+		iio_context_info_list_free(scan_result.info);
+	return ret;
 }
 
 void iio_context_info_list_free(struct iio_context_info **list)
 {
-	struct iio_context_info **it;
-
-	if (!list)
-		return;
+	unsigned int i;
 
-	for (it = list; *it; it++) {
-		struct iio_context_info *info = *it;
-
-		free(info->description);
-		free(info->uri);
-		free(info);
+	for (i = 0; list && list[i]; i++) {
+		free(list[i]->description);
+		free(list[i]->uri);
+		free(list[i]);
 	}
 
 	free(list);
@@ -113,6 +140,8 @@ struct iio_scan_context * iio_create_scan_context(
 		const char *backend, unsigned int flags)
 {
 	struct iio_scan_context *ctx;
+	char *ptr, *ptr2;
+	unsigned int i, len;
 
 	/* "flags" must be zero for now */
 	if (flags != 0) {
@@ -126,20 +155,39 @@ struct iio_scan_context * iio_create_scan_context(
 		return NULL;
 	}
 
-	if (!backend || strstr(backend, "local"))
-		ctx->scan_local = true;
-
-	if (!backend || strstr(backend, "usb"))
-		ctx->scan_usb = true;
+	ctx->backendopts = iio_strndup(backend ? backend : "local,usb,ip", PATH_MAX);
+	if (!ctx->backendopts) {
+		free(ctx);
+		errno = ENOMEM;
+		return NULL;
+	}
 
-	if (!backend || strstr(backend, "ip"))
-		ctx->scan_network = true;
+	if (backend) {
+		/* Replace the colon separator with a comma. */
+		len = strlen(ctx->backendopts);
+		for (i = 0; i < len; i++)
+			if (ctx->backendopts[i] == ':')
+				ctx->backendopts[i] = ',';
+
+		/* The only place where a colon is accepted is in the usb arguments:
+		 * usb=vid:pid */
+		for (ptr = strstr(ctx->backendopts, "usb="); ptr;
+		     ptr = strstr(ptr, "usb=")) {
+			ptr += sizeof("usb=");
+			strtoul(ptr, &ptr2, 16);
+
+			/* The USB backend will take care of errors */
+			if (ptr2 != ptr && *ptr2 == ',')
+				*ptr2 = ':';
+		}
+	}
 
 	return ctx;
 }
 
 void iio_scan_context_destroy(struct iio_scan_context *ctx)
 {
+	free(ctx->backendopts);
 	free(ctx);
 }
 

sort.c

@@ -81,3 +81,20 @@ int iio_buffer_attr_compare(const void *p1, const void *p2)
 	return strcmp(tmp1, tmp2);
 }
 
+int iio_context_info_compare(const void *p1, const void *p2)
+{
+	int ret;
+	const struct iio_context_info *tmp1 = *(struct iio_context_info **)p1;
+	const struct iio_context_info *tmp2 = *(struct iio_context_info **)p2;
+
+	if(!tmp1->uri)
+		return 1;
+	if (!tmp2->uri)
+		return 0;
+
+	ret = strcmp(tmp1->uri, tmp2->uri);
+	if (ret)
+		return ret;
+
+	return strcmp(tmp1->description, tmp2->description);
+}

sort.h

@@ -14,5 +14,6 @@ int iio_channel_attr_compare(const void *p1, const void *p2);
 int iio_device_compare(const void *p1, const void *p2);
 int iio_device_attr_compare(const void *p1, const void *p2);
 int iio_buffer_attr_compare(const void *p1, const void *p2);
+int iio_context_info_compare(const void *p1, const void *p2);
 
 #endif /* __IIO_QSORT_H__ */

tests/iio_adi_xflow_check.c

@@ -168,6 +168,7 @@ int main(int argc, char **argv)
 	char unit;
 	int ret;
 	struct option *opts;
+	bool do_scan = false;
 
 	argw = dup_argv(MY_NAME, argc, argv);
 
@@ -188,6 +189,8 @@ int main(int argc, char **argv)
 		case 'T':
 			break;
 		case 'S':
+			do_scan = true;
+			/* FALLTHROUGH */
 		case 'a':
 			if (!optarg && argc > optind && argv[optind] != NULL
 					&& argv[optind][0] != '-')
@@ -215,6 +218,9 @@ int main(int argc, char **argv)
 	}
 	free(opts);
 
+	if (do_scan)
+		return EXIT_SUCCESS;
+
 	if (optind + 1 != argc) {
 		fprintf(stderr, "Incorrect number of arguments.\n\n");
 		usage(MY_NAME, options, options_descriptions);