colin/iio-sensor-proxy
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

iio-buffer-utils: Correctly disable sensors when exiting

Browse Source 
The enable_sensors() function has an error preventing sensor
disabling: it checks if the sensor is already enabled and does nothing
even if we need to disable it.

Also, there is lack of error handling in the _write_sysfs_int()
function: the result of fprintf() is not checked. If some error occurs
during writing to the sysfs attribute, it is ignored.

Fix these errors and change the order of sysfs attribute writing during
device releasing to avoid "Device or resource busy" errors (a buffer
should be disabled before scan elements).
This commit is contained in:
Yauhen Kharuzhy
2024-01-01 23:17:01 +02:00
parent 408f75ff29
commit 1f5069d13f
1 changed files with 34 additions and 17 deletions
Download Patch File Download Diff File Expand all files Collapse all files

51
src/iio-buffer-utils.c
View File

@@ -356,27 +356,38 @@ _write_sysfs_int (const char *filename,
int ret = 0;
g_autoptr(FILE) sysfsfp = NULL;
int test;
char *temp;
g_autofree char *temp = NULL;
temp = g_build_filename (basedir, filename, NULL);
sysfsfp = fopen(temp, "w");
if (sysfsfp == NULL) {
g_warning ("Could not open for write '%s'", temp);
ret = -errno;
goto error_free;
return -errno;
}
setvbuf(sysfsfp, NULL, _IONBF, 0);
if (type)
fprintf(sysfsfp, "%d %d", val, val2);
ret = fprintf(sysfsfp, "%d %d", val, val2);
else
fprintf(sysfsfp, "%d", val);
ret = fprintf(sysfsfp, "%d", val);
g_clear_pointer (&sysfsfp, fclose);
if (ret < 0) {
g_warning ("Could not write to '%s': %s", temp, g_strerror(-ret));
return ret;
}
ret = 0;
if (verify) {
sysfsfp = fopen(temp, "r");
if (sysfsfp == NULL) {
g_warning ("Could not open for read '%s'", temp);
ret = -errno;
goto error_free;
return -errno;
}
if (fscanf(sysfsfp, "%d", &test) != 1 ||
test != val) {
g_warning ("Possible failure in int write %d to %s",
@@ -384,8 +395,7 @@ _write_sysfs_int (const char *filename,
ret = -1;
}
}
error_free:
g_free (temp);
return ret;
}
@@ -673,6 +683,9 @@ enable_sensors (GUdevDevice *dev,
gboolean ret = FALSE;
g_autoptr(GError) error = NULL;
g_debug ("%s sensors for device '%s'", enable ? "Enabling" : "Disabling",
g_udev_device_get_sysfs_path (dev));
device_dir = g_build_filename (g_udev_device_get_sysfs_path (dev), "scan_elements", NULL);
dir = g_dir_open (device_dir, 0, &error);
if (!dir) {
@@ -689,7 +702,7 @@ enable_sensors (GUdevDevice *dev,
/* Already enabled? */
path = g_strdup_printf ("scan_elements/%s", name);
if (g_udev_device_get_sysfs_attr_as_boolean (dev, path)) {
if (enable && g_udev_device_get_sysfs_attr_as_boolean (dev, path)) {
g_debug ("Already enabled sensor %s/%s", device_dir, name);
ret = TRUE;
g_free (path);
@@ -699,18 +712,21 @@ enable_sensors (GUdevDevice *dev,
/* Enable */
if (write_sysfs_int (name, device_dir, enable) < 0) {
g_warning ("Could not enable sensor %s/%s", device_dir, name);
g_warning ("Could not write %d to %s/%s",
enable, device_dir, name);
continue;
}
ret = TRUE;
g_debug ("Enabled sensor %s/%s", device_dir, name);
g_debug ("%s sensor %s/%s", enable ? "Enabled" : "Disabled",
device_dir, name);
}
g_dir_close (dir);
g_free (device_dir);
if (!ret) {
g_warning ("Failed to enable any sensors for device '%s'",
g_warning ("Failed to %s any sensors for device '%s'",
enable ? "enable" : "disable",
g_udev_device_get_sysfs_path (dev));
}
@@ -785,13 +801,14 @@ buffer_drv_data_free (BufferDrvData *buffer_data)
if (buffer_data == NULL)
return;
/* A buffer should be disabled before scan elements to avoid a
* "Device or resource busy" error */
disable_ring_buffer (buffer_data);
g_free (buffer_data->trigger_name);
enable_sensors (buffer_data->device, 0);
g_clear_object (&buffer_data->device);
disable_ring_buffer (buffer_data);
g_free (buffer_data->trigger_name);
for (i = 0; i < buffer_data->channels_count; i++)
channel_info_free (buffer_data->channels[i]);
g_free (buffer_data->channels);