feat: iterate usb devices and find compatible ones

README.md

@@ -6,7 +6,7 @@ A Linux tool for configuring Honeywell barcode scanners via USB.
 
 ## Why?
 
-I had obtained a used Honeywell Hyperion 1300G scanner, however it was locked down and secured with a password, and the password was unknown.
+I had obtained a used Honeywell barcode scanner, however it was locked down and secured with a password, and the password was unknown.
 
 There is a Windows-only configuration tool from Honeywell called "EZconfig" with which the barcode scanners can be configured via USB, even when locked down.
 
@@ -19,26 +19,22 @@ First of all, compile the program using `make`.  It depends only on `libusb-1.0`
 The configuration commands can be provided either as CLI arguments or via stdin; if CLI commands are present, stdin is ignrored.
 
 ```
-honeywell-config [-v vendor] [-p product] [-1] [-c] [-r] [-d] [-i infile] [-o outfile] [command1 [... commandN]]
-  -v vendor     USB vendor ID of the barcode scanner
-  -p product    USB product ID of the barcode scanner
-  -1            Print response on one line, rather than one token per line
+./honeywell-config [-v vendor] [-p product] [-1] [-c] [-r] [-d] [-i infile] [-o outfile] [command1 [... commandN]]
+  -v vendor     USB vendor ID of the barcode scanner to configure.
+  -p product    USB product ID of the barcode scanner to configure.
+  -s serial     USB serial number of the barcode scanner to configure.
+  -1            Print response on one line, rather than one token per line.
   -c            Print only received commands that contain an argument.  Useful for config backups.
-  -r            Reset device after configuration
-  -d            Debug mode (more verbose output)
-  -i infile     Read input from infile instead of stdin
-  -o outfile    Write output to outfile instead of stdout
-  -h            Show this help
-  -V            Show the version number
+  -r            Reset device after configuration.
+  -d            Debug mode (more verbose output).  Can be provided repeatedly to increase verbosity.
+  -i infile     Read input from infile instead of stdin.
+  -o outfile    Write output to outfile instead of stdout.
+  -h            Show this help and exit.
+  -V            Show the version number and exit.
 ```
 
-If no vendor ID or product ID is provided, the following set of IDs is tried:
-
-- `0c2e:0b01` (Honeywell 1300G, USB Kkeyboard mode PC)
-- `0c2e:0b02` (Honeywell 1300G, USB Keyboard Apple)
-- `0c2e:0b07` (Honeywell 1300G, USB HID POS mode)
-
-USB serial mode (`0c2e:0b0a`) is skipped because USB configuration does not seem to work for it (and it isn't found by EZconfig either).
+All USB devices on the host are iterated, and the first one with an EZConfig configuration endpoint is chosen.
+If there are multiple compatible devices on the host, you can control which device is selected by providing a vendor ID, product ID or serial number.
 
 For the actual configuration commands, please refer to your scanner's manual.  Here are some examples.
 
@@ -52,14 +48,7 @@ To only retrieve the config commands that have a value associated with them, use
 $ honeywell-config -c -o scanner.conf
 ```
 
-This configuration can be restored the the scanner by providing it as an input file using `-i`.  Each sent config command should be acknowledged
-- `0c2e:0b01` (Honeywell 1300G, USB Kkeyboard mode PC)
-- `0c2e:0b02` (Honeywell 1300G, USB Keyboard Apple)
-- `0c2e:0b07` (Honeywell 1300G, USB HID POS mode)
-
-USB serial mode (`0c2e:0b0a`) is skipped because USB configuration does not seem to work for it (and it isn't found by EZconfig either).
- by the scanner and printed to stdout:
-
+This configuration can be restored the the scanner by providing it as an input file using `-i`.  Each sent config command should be acknowledged by the scanner and printed to stdout:
 
 ```shell-session
 $ honeywell-config -i scanner.conf

honeywell-config.c

@@ -17,6 +17,7 @@
 
 #define ISSTATUS(c) (*c == S_ENQ || *c == S_ACK || *c == S_NAK)
 #define USBERR(msg, rc) { dprintf(2, "%s: %s\n", msg, libusb_strerror(rc)); }
+#define USBDEBUG2(msg, rc) { if (debug >= 3) { dprintf(2, "%s: %s\n", msg, libusb_strerror(rc)); } }
 #define DEBUG(...) { if (debug >= 1) { dprintf(2, __VA_ARGS__); } }
 #define DEBUG2(...) { if (debug >= 2) { dprintf(2, __VA_ARGS__); } }
 #define DEBUG3(...) { if (debug >= 3) { dprintf(2, __VA_ARGS__); } }
@@ -25,6 +26,7 @@
 
 uint16_t vendor_id = 0;
 uint16_t product_id = 0;
+char *serial_number = NULL;
 uint8_t reset = 0;
 uint8_t oneline = 0;
 uint8_t onlyargs = 0;
@@ -35,14 +37,8 @@ uint8_t explicit_in = 0;
 
 libusb_device_handle *devh = NULL;
 uint8_t endpoint = 0;
-
-
-uint32_t vidpid[] = {
-  0x0c2e0b01,
-  0x0c2e0b02,
-  0x0c2e0b07,
-};
-
+uint8_t ints[32] = { 0 };
+uint8_t inti = 0;
 
 struct tokenizer {
   char tokbuf[1024];
@@ -225,95 +221,61 @@ int config(int argc, char **args) {
 }
 
 
-int usb(int argc, char **args) {
-  libusb_context *ctx = NULL;
-  libusb_device *dev = NULL;
+int check_device(libusb_device *dev) {
   struct libusb_device_descriptor devd = { 0 };
   struct libusb_config_descriptor *devc = NULL;
   const struct libusb_interface *devi = NULL;
   const struct libusb_interface_descriptor *devid = NULL;
   const struct libusb_endpoint_descriptor *deved = NULL;
   char devdesc[256] = { 0 };
-  int rc = 0, fail = 0;
 
-  uint8_t ints[32] = { 0 };
-  uint8_t inti = 0;
-
-  //
-  // Find and open the device
-  //
-  rc = libusb_init(&ctx);
-  if (!ctx) {
-    USBERR("failed to initialize libusb", rc);
-    fail = 1;
-    goto fail;
-  }
-
-  if (vendor_id || product_id) {
-    devh = libusb_open_device_with_vid_pid(ctx, vendor_id, product_id);
-    if (!devh) {
-      dprintf(2, "device %04x:%04x not found\n", vendor_id, product_id);
-      fail = 1;
-      goto fail;
-    }
-  } else {
-    devh = NULL;
-    for (uint8_t i = 0; i < sizeof(vidpid)/sizeof(vidpid[0]) && !devh; ++i) {
-      devh = libusb_open_device_with_vid_pid(ctx, vidpid[i] >> 16, vidpid[i] & 0xffff);
-    }
-    if (!devh) {
-      dprintf(2, "default devices not found, please provide vendor and product id\n");
-      fail = 1;
-      goto fail;
-    }
-  }
-
-  // Get endpoint infos
-  dev = libusb_get_device(devh);
-  rc = libusb_get_device_descriptor(dev, &devd);
+  // Top-level checks against VID, PID and Serial
+  int rc = libusb_get_device_descriptor(dev, &devd);
   if (rc) {
-    USBERR("failed to get device descriptor", rc);
-    fail = 1;
-    goto fail;
+    USBDEBUG2("failed to get device descriptor", rc);
+    return rc;
   }
-
-  // Print device info
-  rc = libusb_get_string_descriptor_ascii(devh, devd.iManufacturer, (uint8_t *) devdesc, 256);
+  if (vendor_id && vendor_id != devd.idVendor) {
+    return 1;
+  }
+  if (product_id && product_id != devd.idProduct) {
+    return 1;
+  }
+  rc = libusb_open(dev, &devh);
   if (rc < 0) {
-    USBERR("failed to get manufacturer string descriptor", rc);
-    fail = 1;
-    goto fail;
+    USBDEBUG2("failed to open device", rc);
+    return rc;
   }
-  DEBUG("Manufacturer: %s\n", devdesc);
-  rc = libusb_get_string_descriptor_ascii(devh, devd.iProduct, (uint8_t *) devdesc, 256);
-  if (rc < 0) {
-    USBERR("failed to get product string descriptor", rc);
-    fail = 1;
-    goto fail;
+  if (serial_number) {
+    rc = libusb_get_string_descriptor_ascii(devh, devd.iSerialNumber, (uint8_t *) devdesc, 256);
+    if (rc < 0) {
+      libusb_close(devh);
+      devh = NULL;
+      USBDEBUG2("failed to get serial id string descriptor", rc);
+      return rc;
+    }
+    if (strncmp(serial_number, devdesc, strlen(serial_number))) {
+      libusb_close(devh);
+      devh = NULL;
+      return 1;
+    }
   }
-  DEBUG("Product: %s\n", devdesc);
-  rc = libusb_get_string_descriptor_ascii(devh, devd.iSerialNumber, (uint8_t *) devdesc, 256);
-  if (rc < 0) {
-    USBERR("failed to get serial number string descriptor", rc);
-    fail = 1;
-    goto fail;
-  }
-  DEBUG("Serial Number: %s\n", devdesc);
 
   // Iterate all configurations, interfaces and endpoints to find the REM/EZConfig endpoint
   for (uint8_t c = 0; c < devd.bNumConfigurations; ++c) {
     libusb_free_config_descriptor(devc);
     rc = libusb_get_config_descriptor(dev, c, &devc);
     if (rc) {
-      USBERR("failed to get config descriptor", rc);
+      USBDEBUG2("failed to get config descriptor", rc);
       continue;
     }
     rc = libusb_get_string_descriptor_ascii(devh, devc->iConfiguration, (uint8_t *) devdesc, 256);
     if (rc < 0) {
-      USBERR("failed to get config string descriptor", rc);
+      USBDEBUG2("failed to get config string descriptor", rc);
       continue;
     }
     DEBUG2("- configuration %d: %s\n", c, devdesc);
+    inti = 0;
     for (uint8_t i = 0; i < devc->bNumInterfaces; ++i) {
       DEBUG2("  - interface %d\n", i);
       devi = &(devc->interface[i]);
@@ -321,7 +283,7 @@ int usb(int argc, char **args) {
 	devid = &(devi->altsetting[a]);
 	rc = libusb_get_string_descriptor_ascii(devh, devid->iInterface, (uint8_t *) devdesc, 256);
 	if (rc < 0) {
-	  USBERR("failed to get interface string descriptor", rc);
+	  USBDEBUG2("failed to get interface string descriptor", rc);
 	  continue;
 	}
 	DEBUG2("    - altsetting %d: interface=%d, desc=%s class=%d subclass=%d protocol=%d\n",
@@ -339,13 +301,79 @@ int usb(int argc, char **args) {
 	      && !strncmp("REM", devdesc, 3)  // human readable description of the interface must be "REM" (Honeywell "Remote MasterMind" control interface)
 	      ) {
 	    endpoint = deved->bEndpointAddress;
+	    // Print device info
+	    rc = libusb_get_string_descriptor_ascii(devh, devd.iManufacturer, (uint8_t *) devdesc, 256);
+	    if (rc < 0) {
+	      USBDEBUG2("failed to get manufacturer string descriptor", rc);
+	      libusb_close(devh);
+	      devh = NULL;
+	      return 1;
+	    }
+	    DEBUG("Manufacturer: %s\n", devdesc);
+	    rc = libusb_get_string_descriptor_ascii(devh, devd.iProduct, (uint8_t *) devdesc, 256);
+	    if (rc < 0) {
+	      USBDEBUG2("failed to get product string descriptor", rc);
+	      libusb_close(devh);
+	      devh = NULL;
+	      return 1;
+	    }
+	    DEBUG("Product: %s\n", devdesc);
+	    rc = libusb_get_string_descriptor_ascii(devh, devd.iSerialNumber, (uint8_t *) devdesc, 256);
+	    if (rc < 0) {
+	      USBDEBUG2("failed to get serial number string descriptor", rc);
+	      libusb_close(devh);
+	      devh = NULL;
+	      return 1;
+	    }
+	    DEBUG("Serial Number: %s\n", devdesc);
+	    DEBUG2("chose endpoint %x\n", endpoint);
+	    return 0;
 	  }
 	}
       }
     }
   }
+  libusb_close(devh);
+  devh = NULL;
+  return 1;
+}
 
-  DEBUG2("chose endpoint %x\n", endpoint);
+
+int usb(int argc, char **args) {
+  libusb_context *ctx = NULL;
+  libusb_device **list = NULL;
+  int rc = 0, fail = 0;
+
+  //
+  // Find and open the device
+  //
+  rc = libusb_init(&ctx);
+  if (!ctx) {
+    USBERR("failed to initialize libusb", rc);
+    fail = 1;
+    goto fail;
+  }
+
+  //
+  // Iterate list of USB devices
+  //
+  ssize_t ndev = libusb_get_device_list(ctx, &list);
+  if (ndev < 0) {
+    USBERR("failed to list usb devices", ndev);
+    fail = 1;
+    goto fail;
+  }
+  for (size_t i = 0; i < ndev; ++i) {
+    rc = check_device(list[i]);
+    if (!rc) {
+      break;
+    }
+  }
+  if (!devh) {
+    dprintf(2, "failed to find compatible device\n");
+    fail = 1;
+    goto fail;
+  }
 
   //
   // Disconnect usbhid driver from both device interfaces
@@ -405,6 +433,9 @@ int usb(int argc, char **args) {
     }
     libusb_close(devh);
   }
+  if (list) {
+    libusb_free_device_list(list, 1);
+  }
   if (ctx) {
     libusb_exit(ctx);
   }
@@ -416,7 +447,7 @@ int main(int argc, char **argv) {
   int opt;
   char *end;
   long parsed;
-  while ((opt = getopt(argc, argv, "v:p:1crdi:o:hV")) != -1) {
+  while ((opt = getopt(argc, argv, "v:p:s:1crdi:o:hV")) != -1) {
     switch (opt) {
     case 'v':
       end = optarg;
@@ -444,6 +475,9 @@ int main(int argc, char **argv) {
       }
       product_id = (uint16_t) parsed;
       break;
+    case 's':
+      serial_number = strdup(optarg);
+      break;
     case 'r':
       reset = 1;
       break;
@@ -487,6 +521,7 @@ int main(int argc, char **argv) {
       printf("%s [-v vendor] [-p product] [-1] [-c] [-r] [-d] [-i infile] [-o outfile] [command1 [... commandN]]\n", argv[0]);
       puts("  -v vendor\tUSB vendor ID of the barcode scanner to configure.");
       puts("  -p product\tUSB product ID of the barcode scanner to configure.");
+      puts("  -s serial\tUSB serial number of the barcode scanner to configure.");
       puts("  -1\t\tPrint response on one line, rather than one token per line.");
       puts("  -c\t\tPrint only received commands that contain an argument.  Useful for config backups.");
       puts("  -r\t\tReset device after configuration.");