commit 57de4d50cb0dfdc391386a7383a82dcfb47fbb38
parent e70905eea22e5bd5dd21607d73eeaaf3547aa677
Author: Boss Marco <bossm8@students.bfh.ch>
Date: Tue, 10 Dec 2019 16:28:46 +0100
commented code
Diffstat:
| M | src/main.c | | | 76 | +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++----------- |
1 file changed, 65 insertions(+), 11 deletions(-)
diff --git a/src/main.c b/src/main.c
@@ -24,7 +24,7 @@ along with
* @author Dominik Hofer
*
* TODO:
-* - comment code (Boss)
+* - comment code mdb incl. doxygen struct members (hofer)
*/
#include "config.h"
#include <stdio.h>
@@ -552,8 +552,19 @@ static char *framebuffer_device_filename;
*/
static char *framebuffer_backlight_filename;
+/**
+ * Global option '-i' to invert backlight on/off values
+ */
static int backlight_invert;
+
+/**
+ * Standard backlight on value
+ */
static char backlight_on = '1';
+
+/**
+ * Standard backlight off value
+ */
static char backlight_off = '0';
/**
@@ -689,12 +700,13 @@ show_qrcode (const char *uri)
return;
}
- /* +8 for 4-pixels border */
+ /* set QR-code border */
size = GNUNET_MIN (qrDisplay.var_info.xres,
qrDisplay.var_info.yres);
- unsigned int nwidth = qrc->width + 8; /* 4 pixel border */
+ unsigned int nwidth = qrc->width + 8; /* +8 for 4 pixel border */
xOff = 4 * size / nwidth;
yOff = 4 * size / nwidth;
+ /* calculate offset to show the code centered */
if (qrDisplay.var_info.xres < qrDisplay.var_info.yres)
yOff += (qrDisplay.var_info.yres - qrDisplay.var_info.xres) / 2;
else
@@ -708,6 +720,7 @@ show_qrcode (const char *uri)
if ( (xoff >= (unsigned) qrc->width) ||
(yoff >= (unsigned) qrc->width) )
continue;
+ /* set the pixels in the display memory */
qrDisplay.memory[(y + yOff) * qrDisplay.var_info.xres + (x + xOff)] =
(0 == (qrc->data[off] & 1)) ? 0xFFFF : 0x0000;
}
@@ -715,11 +728,11 @@ show_qrcode (const char *uri)
QRcode_free (qrc);
QRinput_free (qri);
+ /* turn on backlight if supported */
if (0 < qrDisplay.backlightfd)
(void) write (qrDisplay.backlightfd, &backlight_on, 1);
}
-
#endif
@@ -729,6 +742,7 @@ run_mdb_event_loop (void);
/**
* @brief Cleanup all the data when a order has succeeded or got cancelled
+ *
* @param pa the payment activity to clean up
*/
static void
@@ -873,13 +887,14 @@ shutdown_task (void *cls)
GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
"failed to reset originial display state\n");
}
- /* close device */
+ /* close the device */
close (qrDisplay.devicefd);
qrDisplay.devicefd = -1;
if (0 < qrDisplay.backlightfd)
close (qrDisplay.backlightfd);
qrDisplay.backlightfd = -1;
}
+ /* free the allocated productes read from config file */
if (NULL != products)
{
for (unsigned int i = 0; i < products_length; i++)
@@ -914,13 +929,16 @@ static void
wallet_transmit_uri (void *cls)
{
struct PaymentActivity *pa = cls;
+ /* response array for APDU response status word */
uint8_t response[] = { 0x00, 0x00 };
size_t slen = strlen (pa->taler_pay_uri);
uint8_t message[sizeof (put_data) + slen];
pa->delay_task = NULL;
+ /* append the pay uri to the put data command */
memcpy (message, put_data, sizeof (put_data));
memcpy (&message[sizeof (put_data)], pa->taler_pay_uri, slen);
+ /* send the put data command via nfc */
GNUNET_log (GNUNET_ERROR_TYPE_INFO,
"Sending 'PUT DATA' command for `%s' to wallet\n",
pa->taler_pay_uri);
@@ -937,6 +955,7 @@ wallet_transmit_uri (void *cls)
pa);
return;
}
+ /* check if the transmission succeeded */
if (0 != memcmp (response,
APDU_SUCCESS,
sizeof (response)))
@@ -953,6 +972,10 @@ wallet_transmit_uri (void *cls)
"'PUT DATA' command sent successfully via NFC\n");
pa->wallet_has_uri = GNUNET_YES;
/* FIXME: or just offer Internet service here? */
+
+ /* transmit the uri again later, there can be many external failures,
+ for example the taler wallet app was not opened and thus did not receive
+ the data */
pa->delay_task = GNUNET_SCHEDULER_add_delayed (MAX_HTTP_RETRY_FREQ,
&wallet_transmit_uri,
pa);
@@ -960,7 +983,9 @@ wallet_transmit_uri (void *cls)
/**
- * @brief Select the taler wallet app via NFC
+ * @brief Select the taler wallet app via NFC on the target selected with
+ * @e connect_target()
+ * (check if it is installed on the smartphone)
*
* @param cls closure
*/
@@ -968,13 +993,16 @@ static void
wallet_select_aid (void *cls)
{
struct PaymentActivity *pa = cls;
+ /* response array for APDU response status word */
uint8_t response[] = { 0x00, 0x00 };
uint8_t message[sizeof(select_file) + sizeof(taler_aid)];
pa->task = NULL;
+ /* append the taler wallet aid to the select file command */
memcpy (message, select_file, sizeof (select_file));
memcpy (&message[sizeof (select_file)], taler_aid, sizeof (taler_aid));
+ /* send the select file command via nfc */
GNUNET_log (GNUNET_ERROR_TYPE_INFO,
"Trying to find Taler wallet on NFC\n");
if (0 > nfc_initiator_transceive_bytes (pa->pnd,
@@ -990,6 +1018,7 @@ wallet_select_aid (void *cls)
pa);
return;
}
+ /* check if the transmission succeeded */
if (0 == memcmp (response,
APDU_SUCCESS,
sizeof (response)))
@@ -1000,6 +1029,7 @@ wallet_select_aid (void *cls)
pa);
return;
}
+ /* if the transmission was not successful chack if the app is available at all */
if (0 == memcmp (response,
APDU_NOT_FOUND,
sizeof (response)))
@@ -1010,10 +1040,12 @@ wallet_select_aid (void *cls)
pa);
return;
}
+ /* If the upper cases did not match, there was an unknown APDU status returned */
GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
"AID selection failure, return code: %x%x, trying to find another NFC client\n",
response[0],
response[1]);
+ /* start the selection again */
pa->task = GNUNET_SCHEDULER_add_delayed (NFC_FAILURE_RETRY_FREQ,
&connect_target,
pa);
@@ -1029,13 +1061,16 @@ static void
connect_target (void *cls)
{
struct PaymentActivity *pa = cls;
+ /* nfc modulation used */
const nfc_modulation nmMifare = {
.nmt = NMT_ISO14443A,
.nbr = NBR_212,
};
pa->task = NULL;
+ /* set the uid len to zero (maybe it is still set from earlier selections) */
pa->nt.nti.nai.szUidLen = 0;
+ /* poll for a fitting nfc target (we use the shortest time possible to not block the scheduler) */
GNUNET_log (GNUNET_ERROR_TYPE_INFO,
"Trying to find NFC client\n");
if (0 > nfc_initiator_poll_target (pa->pnd,
@@ -1048,6 +1083,7 @@ connect_target (void *cls)
GNUNET_log (GNUNET_ERROR_TYPE_INFO,
"Failed to connect to NFC target\n");
}
+ /* if the uid lenght are out of bound abort */
else if ( (pa->nt.nti.nai.szUidLen > UID_LEN_UPPER) ||
(pa->nt.nti.nai.szUidLen < UID_LEN_LOWER) )
{
@@ -1056,12 +1092,15 @@ connect_target (void *cls)
}
else
{
+ /* the target was successfully selected,
+ now we have to check if the taler wallet is installed on it */
GNUNET_log (GNUNET_ERROR_TYPE_INFO,
"Found NFC client\n");
pa->task = GNUNET_SCHEDULER_add_now (&wallet_select_aid,
pa);
return;
}
+ /* if no target was found try again */
pa->task = GNUNET_SCHEDULER_add_delayed (NFC_FAILURE_RETRY_FREQ,
&connect_target,
pa);
@@ -1079,6 +1118,7 @@ open_nfc_reader (void *cls)
struct PaymentActivity *pa = cls;
pa->task = NULL;
+ /* open the nfc reader via libnfc's open */
GNUNET_log (GNUNET_ERROR_TYPE_INFO,
"Trying to open NFC device\n");
pa->pnd = nfc_open (context, NULL);
@@ -1091,6 +1131,7 @@ open_nfc_reader (void *cls)
pa);
return;
}
+ /* initialize the reader as initiator */
if (0 > nfc_initiator_init (pa->pnd))
{
GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
@@ -1105,6 +1146,7 @@ open_nfc_reader (void *cls)
"NFC in operation %s / %s\n",
nfc_device_get_name (pa->pnd),
nfc_device_get_connstring (pa->pnd));
+ /* the nfc reader was opened successfully, now try to find a mobile device as a target */
pa->task = GNUNET_SCHEDULER_add_now (&connect_target,
pa);
}
@@ -1319,6 +1361,7 @@ launch_payment (const struct Product *product)
}
pa = GNUNET_new (struct PaymentActivity);
pa->amount = product->price;
+ /* put the order on the merchant's backend */
pa->po = TALER_MERCHANT_order_put (ctx,
backendBaseUrl,
orderReq,
@@ -2051,7 +2094,7 @@ run_mdb_event_loop ()
/**
* @brief Read the products from the configuration file
*
- * @param cls closure
+ * @param cls closure in this case the name of the configuration file to read from
* @param section section of the config file to read from
*/
static void
@@ -2061,10 +2104,12 @@ read_products (void *cls,
struct Product tmpProduct;
char *tmpKey;
+ /* if the current section is not a product skip it */
if (0 != strncmp (section,
"product-",
strlen ("product-")))
return;
+ /* the current section is a product, parse its specifications and store it in a temporary product */
if (GNUNET_OK !=
GNUNET_CONFIGURATION_get_value_string (cls,
section,
@@ -2124,6 +2169,7 @@ read_products (void *cls,
GNUNET_free (tmpProduct.description);
return;
}
+ /* append the temporary product to the existing products */
GNUNET_array_append (products,
products_length,
tmpProduct);
@@ -2218,6 +2264,7 @@ run (void *cls,
(void) args;
(void) cfgfile;
+ /* parse the configuration file */
if (GNUNET_OK !=
GNUNET_CONFIGURATION_get_value_string (cfg,
"taler",
@@ -2230,6 +2277,7 @@ run (void *cls,
global_ret = EXIT_FAILURE;
return;
}
+ /* parse the devices, if no config entry is found, a standard is used */
if (GNUNET_OK !=
GNUNET_CONFIGURATION_get_value_filename (cfg,
"taler-mdb",
@@ -2264,6 +2312,7 @@ run (void *cls,
framebuffer_backlight_filename = GNUNET_strdup (
"/sys/class/backlight/soc:backlight/brightness");
}
+ /* parse the taler configurations */
if (GNUNET_OK !=
GNUNET_CONFIGURATION_get_value_string (cfg,
"taler-mdb",
@@ -2290,6 +2339,7 @@ run (void *cls,
global_ret = EXIT_FAILURE;
return;
}
+ /* concat the authorization e.g. Authorization: ApiKey sandbox */
GNUNET_asprintf (&authorization,
"%s: %s",
MHD_HTTP_HEADER_AUTHORIZATION,
@@ -2320,6 +2370,7 @@ run (void *cls,
global_ret = EXIT_FAILURE;
return;
}
+ /* parse the products */
GNUNET_CONFIGURATION_iterate_sections (cfg,
&read_products,
(void *) cfg);
@@ -2402,20 +2453,20 @@ run (void *cls,
PROT_READ | PROT_WRITE, MAP_SHARED,
qrDisplay.devicefd,
0);
-
- /* open backlight file to turn display backlight on and off */
- if (0 > qrDisplay.devicefd)
+ if (0 > qrDisplay.memory)
{
GNUNET_log_strerror (GNUNET_ERROR_TYPE_WARNING,
"mmap");
return;
}
+ /* set the screen to white */
memset (qrDisplay.memory,
0xFF,
qrDisplay.var_info.xres * qrDisplay.var_info.yres
* sizeof (uint16_t));
+ /* open backlight file to turn display backlight on and off */
qrDisplay.backlightfd = open (
framebuffer_backlight_filename, O_WRONLY);
if (0 > qrDisplay.backlightfd)
@@ -2426,11 +2477,13 @@ run (void *cls,
}
else
{
+ /* if '-i' flag was set, invert the on and off values */
if (backlight_invert)
{
backlight_on = '0';
backlight_off = '1';
}
+ /* turn off the backlight */
(void) write (qrDisplay.backlightfd, &backlight_off, 1);
}
}
@@ -2506,7 +2559,9 @@ main (int argc,
char*const*argv)
{
struct termios tty_opts_backup, tty_opts_raw;
+ int have_tty;
int ret;
+
/* the available command line options */
struct GNUNET_GETOPT_CommandLineOption options[] = {
GNUNET_GETOPT_option_flag ('d',
@@ -2523,7 +2578,6 @@ main (int argc,
&backlight_invert),
GNUNET_GETOPT_OPTION_END
};
- int have_tty;
if (! disable_tty)
{
