Improve error messages relative to libusb calls failures

[visomat-utils.git] / src / visomat-data-downloader.c

diff --git a/src/visomat-data-downloader.c b/src/visomat-data-downloader.c
index 0eca9c1..f93757d 100644 (file)
--- a/src/visomat-data-downloader.c
+++ b/src/visomat-data-downloader.c
@@ -21,19 +21,21 @@
 
 #include <stdio.h>
 #include <stdlib.h>
+#include <string.h>
 #include <errno.h>
 #include <unistd.h>
 #include <libusb.h>
 
+#define VISOMAT_DEVICE_VID    0x1247
+#define VISOMAT_DEVICE_PID    0x00f8
+#define VISOMAT_CONFIGURATION 1
+#define VISOMAT_INTERFACE     1
+#define VISOMAT_EP_IN         0x82
+#define VISOMAT_EP_OUT        0x03
+
 #define STX 0x02
 #define ETX 0x03
 
-#define DEVICE_VID 0x1247
-#define DEVICE_PID 0x00f8
-
-#define EP_IN 0x82
-#define EP_OUT 0x03
-
 #define BASE_YEAR 2000
 
 typedef enum {
@@ -63,6 +65,7 @@ struct datetime  {
 };
 
 struct pressure  {
+       unsigned int flag; /* XXX Maybe this means arrhythmia? */
        unsigned int systolic;
        unsigned int diastolic;
        unsigned int pulses;
@@ -102,16 +105,24 @@ static void print_record_csv_compat(struct datetime *d, struct pressure *p)
        pulse_pressure = p->systolic - p->diastolic;
        printf("%u;", pulse_pressure);
 
+       if (p->flag)
+               printf("x");
+
+#if 0
+       /* The original software does not seem to be doing that */
        if (p->pulses > 100)
                printf("tachycardia");
        else if (p->pulses < 60)
                printf("bradycardia");
+#endif
 
        printf("\n");
 }
 
 /* TODO separate better decoding data from printing it */
-static int decode_eeprom(unsigned char *buffer, unsigned int len)
+static int decode_eeprom(unsigned char *buffer,
+                        unsigned int len,
+                        unsigned int user_mask)
 {
        int ret;
        unsigned int n;
@@ -137,7 +148,6 @@ static int decode_eeprom(unsigned char *buffer, unsigned int len)
                        /* i tracks the bytes consumed */
                        i += 1;
 
-
                        ret = sscanf((char *)(buffer + i), "%1u%02u",
                                     &user_id, &num_records);
                        if (ret != 2)
@@ -146,8 +156,6 @@ static int decode_eeprom(unsigned char *buffer, unsigned int len)
                        /* user_id and num_records take 3 bytes */
                        i += 3;
 
-                       printf("# User: %d\n", user_id);
-
                        for (j = 0; j < num_records; j++) {
                                ret = extract_datetime(buffer + i, &d);
                                if (ret < 0)
@@ -157,17 +165,23 @@ static int decode_eeprom(unsigned char *buffer, unsigned int len)
                                i += 10;
 
                                ret = sscanf((char *)(buffer + i),
-                                            "%04u%03u%03u",
+                                            "%1u%03u%03u%03u",
+                                            &p.flag,
                                             &p.systolic,
                                             &p.diastolic,
                                             &p.pulses);
-                               if (ret != 3)
+                               if (ret != 4)
                                        return -EINVAL;
 
                                /* pressure data is 10 bytes */
                                i += 10;
 
-                               print_record_csv_compat(&d, &p);
+                               /* TODO: split out the printing part */
+                               if (user_id & user_mask) {
+                                       if (j == 0)
+                                               printf("# User: %d\n", user_id);
+                                       print_record_csv_compat(&d, &p);
+                               }
                        }
                }
        }
@@ -212,7 +226,7 @@ static int send_command(libusb_device_handle *dev, visomat_command cmd)
        request[4] = ETX;
 
        transferred = 0;
-       ret = libusb_bulk_transfer(dev, EP_OUT, request, sizeof(request), &transferred, 0);
+       ret = libusb_bulk_transfer(dev, VISOMAT_EP_OUT, request, sizeof(request), &transferred, 0);
        if (ret != 0 || transferred != sizeof(request)) {
                fprintf(stderr, "Error: sending request: %d (%s)\ttransferred: %d (expected %zu)\n",
                        ret, libusb_error_name(ret), transferred, sizeof(request));
@@ -235,7 +249,7 @@ static int get_response(libusb_device_handle *dev,
                unsigned int j;
 
                transferred = 0;
-               ret = libusb_bulk_transfer(dev, EP_IN, response, sizeof(response), &transferred, 5000);
+               ret = libusb_bulk_transfer(dev, VISOMAT_EP_IN, response, sizeof(response), &transferred, 5000);
                if (ret != 0) {
                        fprintf(stderr, "Error getting response: %d (%s)\ttransferred: %d (expected %zu)\n",
                                ret, libusb_error_name(ret), transferred, sizeof(response));
@@ -258,7 +272,7 @@ static int get_response(libusb_device_handle *dev,
 
 /* Candidates for a future public API, if a shared library will ever be made */
 #define visomat_device libusb_device_handle
-static int visomat_dump_eeprom(visomat_device *dev)
+static int visomat_dump_eeprom(visomat_device *dev, unsigned int user_mask)
 {
        /* Assuming an EEPROM of 1 KiB  */
        unsigned char buffer[1024] = { 0 };
@@ -272,7 +286,7 @@ static int visomat_dump_eeprom(visomat_device *dev)
        if (ret < 0)
                return ret;
 
-       ret = decode_eeprom(buffer, ret);
+       ret = decode_eeprom(buffer, ret, user_mask);
        if (ret < 0)
                return ret;
 
@@ -304,29 +318,58 @@ int main(void)
        int ret;
        libusb_device_handle *dev;
 
-       libusb_init(NULL);
+       ret = libusb_init(NULL);
+       if (ret < 0) {
+               fprintf(stderr, "libusb_init failed: %s\n", libusb_error_name(ret));
+               goto out;
+       }
+
        libusb_set_debug(NULL, LIBUSB_LOG_LEVEL_INFO);
 
-       dev = libusb_open_device_with_vid_pid(NULL, DEVICE_VID, DEVICE_PID);
+       dev = libusb_open_device_with_vid_pid(NULL,
+                                             VISOMAT_DEVICE_VID,
+                                             VISOMAT_DEVICE_PID);
        if (dev == NULL) {
-               fprintf(stderr, "Couldn't open device.\n");
-               ret = -ENODEV;
+               fprintf(stderr, "libusb_open failed: %s\n", strerror(errno));
+               ret = -errno;
                goto out_libusb_exit;
        }
 
-       libusb_set_configuration(dev, 1);
-       libusb_claim_interface(dev, 1);
-       libusb_detach_kernel_driver(dev, 1);
+       ret = libusb_set_configuration(dev, VISOMAT_CONFIGURATION);
+       if (ret < 0) {
+               fprintf(stderr, "libusb_set_configuration failed: %s\n",
+                       libusb_error_name(ret));
+               fprintf(stderr, "Cannot set configuration %hhu\n",
+                       VISOMAT_CONFIGURATION);
+               goto out_libusb_close;
+       }
+
+       libusb_set_auto_detach_kernel_driver(dev, 1);
+
+       ret = libusb_claim_interface(dev, VISOMAT_INTERFACE);
+       if (ret < 0) {
+               fprintf(stderr, "libusb_claim_interface failed: %s\n",
+                       libusb_error_name(ret));
+               fprintf(stderr, "Cannot claim interface %hhu\n",
+                       VISOMAT_INTERFACE);
+               goto out_libusb_close;
+       }
 
        ret = visomat_get_datetime(dev);
        if (ret < 0)
-               goto out;
+               goto out_libusb_release_interface;
 
-       ret = visomat_dump_eeprom(dev);
+       ret = visomat_dump_eeprom(dev, 0x01 | 0x02);
+       if (ret < 0)
+               goto out_libusb_release_interface;
 
-out:
+out_libusb_release_interface:
+       libusb_release_interface(dev, VISOMAT_INTERFACE);
+out_libusb_close:
        libusb_close(dev);
+       dev = NULL;
 out_libusb_exit:
        libusb_exit(NULL);
+out:
        return ret;
 }