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Diffstat (limited to 'binding/radio_impl_rtlsdr.c')
-rw-r--r--binding/radio_impl_rtlsdr.c78
1 files changed, 46 insertions, 32 deletions
diff --git a/binding/radio_impl_rtlsdr.c b/binding/radio_impl_rtlsdr.c
index 9a1c492..503748e 100644
--- a/binding/radio_impl_rtlsdr.c
+++ b/binding/radio_impl_rtlsdr.c
@@ -32,6 +32,9 @@
#define HELPER_NAME "rtl_fm_helper"
#define HELPER_MAX PATH_MAX + 64
+#define HELPER_CMD_MAXLEN 64
+#define HELPER_RSP_MAXLEN 128
+
// Structure to describe FM band plans, all values in Hz.
typedef struct {
char *name;
@@ -215,8 +218,8 @@ static uint32_t rtlsdr_get_frequency(void)
static void rtlsdr_set_frequency(uint32_t frequency)
{
- char cmd[64];
- char output[128];
+ char cmd[HELPER_CMD_MAXLEN];
+ char output[HELPER_RSP_MAXLEN];
bool found = false;
ssize_t rc;
uint32_t n;
@@ -232,7 +235,7 @@ static void rtlsdr_set_frequency(uint32_t frequency)
rtlsdr_scan_stop();
current_frequency = frequency;
- sprintf(cmd, "F=%u\n", frequency);
+ snprintf(cmd, sizeof(cmd), "F=%u\n", frequency);
pthread_mutex_lock(&helper_mutex);
rc = write(helper_in, cmd, strlen(cmd));
if(rc < 0) {
@@ -240,11 +243,9 @@ static void rtlsdr_set_frequency(uint32_t frequency)
return;
}
while(!found) {
- rc = read(helper_out, output, 128);
+ rc = read(helper_out, output, sizeof(output)-1);
if(rc <= 0)
break;
- if(rc == 128)
- rc = 127;
output[rc] = '\0';
if(output[0] == 'F') {
if(sscanf(output, "F=%u\n", &n) == 1) {
@@ -314,34 +315,43 @@ static void rtlsdr_start(void)
if(!present)
return;
- if(!active) {
- ssize_t rc;
- char cmd[64];
+ if(active)
+ return;
- sprintf(cmd, "START\n");
- pthread_mutex_lock(&helper_mutex);
- rc = write(helper_in, cmd, strlen(cmd));
- pthread_mutex_unlock(&helper_mutex);
- if(rc < 0)
- return;
- active = true;
+ ssize_t rc;
+ char cmd[HELPER_CMD_MAXLEN];
+
+ snprintf(cmd, sizeof(cmd), "START\n");
+ pthread_mutex_lock(&helper_mutex);
+ rc = write(helper_in, cmd, strlen(cmd));
+ pthread_mutex_unlock(&helper_mutex);
+ if (rc < 0) {
+ AFB_ERROR("Failed to ask \"%s\" to start", HELPER_NAME);
+ return;
}
+ active = true;
}
static void rtlsdr_stop(void)
{
+ ssize_t rc;
if(!present)
return;
- if(active) {
- char cmd[64];
+ if (!active)
+ return;
- active = false;
- sprintf(cmd, "STOP\n");
- pthread_mutex_lock(&helper_mutex);
- write(helper_in, cmd, strlen(cmd));
- pthread_mutex_unlock(&helper_mutex);
+ char cmd[HELPER_CMD_MAXLEN];
+
+ snprintf(cmd, sizeof(cmd), "STOP\n");
+ pthread_mutex_lock(&helper_mutex);
+ rc = write(helper_in, cmd, strlen(cmd));
+ pthread_mutex_unlock(&helper_mutex);
+ if (rc < 0) {
+ AFB_ERROR("Failed to ask \"%s\" to stop", HELPER_NAME);
+ return;
}
+ active = false;
}
static void rtlsdr_scan_start(radio_scan_direction_t direction,
@@ -349,8 +359,8 @@ static void rtlsdr_scan_start(radio_scan_direction_t direction,
void *data)
{
ssize_t rc;
- char cmd[64];
- char output[128];
+ char cmd[HELPER_CMD_MAXLEN];
+ char output[HELPER_RSP_MAXLEN];
bool found = false;
uint32_t n;
@@ -358,7 +368,9 @@ static void rtlsdr_scan_start(radio_scan_direction_t direction,
return;
scanning = true;
- sprintf(cmd, "S=%s\n", direction == SCAN_FORWARD ? "UP" : "DOWN");
+ snprintf(cmd,
+ sizeof(cmd),
+ "S=%s\n", direction == SCAN_FORWARD ? "UP" : "DOWN");
pthread_mutex_lock(&helper_mutex);
if(!scanning) {
pthread_mutex_unlock(&helper_mutex);
@@ -374,12 +386,11 @@ static void rtlsdr_scan_start(radio_scan_direction_t direction,
pthread_mutex_unlock(&helper_mutex);
break;
}
- rc = read(helper_out, output, 128);
+ rc = read(helper_out, output, sizeof(output)-1);
pthread_mutex_unlock(&helper_mutex);
if(rc <= 0)
break;
- if(rc == 128)
- rc = 127;
+
output[rc] = '\0';
if(output[0] == 'F') {
if(sscanf(output, "F=%u\n", &n) == 1) {
@@ -401,13 +412,16 @@ static void rtlsdr_scan_start(radio_scan_direction_t direction,
static void rtlsdr_scan_stop(void)
{
- char cmd[64];
+ char cmd[HELPER_CMD_MAXLEN];
+ ssize_t rc;
- sprintf(cmd, "S=STOP\n");
+ snprintf(cmd, sizeof(cmd), "S=STOP\n");
pthread_mutex_lock(&helper_mutex);
scanning = false;
- write(helper_in, cmd, strlen(cmd));
+ rc = write(helper_in, cmd, strlen(cmd));
pthread_mutex_unlock(&helper_mutex);
+ if (rc < 0)
+ AFB_ERROR("Failed to ask \"%s\" to stop scan", HELPER_NAME);
}
static radio_stereo_mode_t rtlsdr_get_stereo_mode(void)