Commit 4f20d592 authored by Crestez Dan Leonard's avatar Crestez Dan Leonard Committed by Jonathan Cameron
Browse files

iio: iio_generic_buffer: Cleanup when receiving signals 



This will clean (disable buffer/trigger/channels) when doing
something like a CTRL-C. Otherwise restarting generic_buffer requires a
manual echo 0 > buffer/enable

This also cleanup up all the code freeing string buffers at
the end of main. We initialize all pointers to NULL so that cleanup can
all be done under a single error label.

Signed-off-by: default avatarCrestez Dan Leonard <leonard.crestez@intel.com>
Signed-off-by: default avatarJonathan Cameron <jic23@kernel.org>
parent 90e9a950

tools/iio/iio_generic_buffer.c

+108 −64
Original line number Diff line number Diff line
@@ -32,6 +32,8 @@ 
#include <endian.h>

#include <getopt.h>

#include <inttypes.h>

#include <stdbool.h>

#include <signal.h>

#include "iio_utils.h"



/**
@@ -254,6 +256,65 @@ void print_usage(void) 
		"  -w <n>     Set delay between reads in us (event-less mode)\n");

}



enum autochan autochannels = AUTOCHANNELS_DISABLED;

char *dev_dir_name = NULL;

char *buf_dir_name = NULL;

bool current_trigger_set = false;



void cleanup(void)

{

	int ret;



	/* Disable trigger */

	if (dev_dir_name && current_trigger_set) {

		/* Disconnect the trigger - just write a dummy name. */

		ret = write_sysfs_string("trigger/current_trigger",

					 dev_dir_name, "NULL");

		if (ret < 0)

			fprintf(stderr, "Failed to disable trigger: %s\n",

				strerror(-ret));

		current_trigger_set = false;

	}



	/* Disable buffer */

	if (buf_dir_name) {

		ret = write_sysfs_int("enable", buf_dir_name, 0);

		if (ret < 0)

			fprintf(stderr, "Failed to disable buffer: %s\n",

				strerror(-ret));

	}



	/* Disable channels if auto-enabled */

	if (dev_dir_name && autochannels == AUTOCHANNELS_ACTIVE) {

		ret = enable_disable_all_channels(dev_dir_name, 0);

		if (ret)

			fprintf(stderr, "Failed to disable all channels\n");

		autochannels = AUTOCHANNELS_DISABLED;

	}

}



void sig_handler(int signum)

{

	fprintf(stderr, "Caught signal %d\n", signum);

	cleanup();

	exit(-signum);

}



void register_cleanup(void)

{

	struct sigaction sa = { .sa_handler = sig_handler };

	const int signums[] = { SIGINT, SIGTERM, SIGABRT };

	int ret, i;



	for (i = 0; i < ARRAY_SIZE(signums); ++i) {

		ret = sigaction(signums[i], &sa, NULL);

		if (ret) {

			perror("Failed to register signal handler");

			exit(-1);

		}

	}

}



int main(int argc, char **argv)

{

	unsigned long num_loops = 2;
@@ -261,25 +322,24 @@ int main(int argc, char **argv) 
	unsigned long buf_len = 128;



	int ret, c, i, j, toread;

	int fp;

	int fp = -1;



	int num_channels;

	int num_channels = 0;

	char *trigger_name = NULL, *device_name = NULL;

	char *dev_dir_name, *buf_dir_name;



	int datardytrigger = 1;

	char *data;

	char *data = NULL;

	ssize_t read_size;

	int dev_num, trig_num;

	char *buffer_access;

	char *buffer_access = NULL;

	int scan_size;

	int noevents = 0;

	int notrigger = 0;

	enum autochan autochannels = AUTOCHANNELS_DISABLED;

	char *dummy;



	struct iio_channel_info *channels;



	register_cleanup();



	while ((c = getopt(argc, argv, "ac:egl:n:t:w:")) != -1) {

		switch (c) {

		case 'a':
@@ -288,8 +348,10 @@ int main(int argc, char **argv) 
		case 'c':

			errno = 0;

			num_loops = strtoul(optarg, &dummy, 10);

			if (errno)

				return -errno;

			if (errno) {

				ret = -errno;

				goto error;

			}



			break;

		case 'e':
@@ -301,26 +363,30 @@ int main(int argc, char **argv) 
		case 'l':

			errno = 0;

			buf_len = strtoul(optarg, &dummy, 10);

			if (errno)

				return -errno;

			if (errno) {

				ret = -errno;

				goto error;

			}



			break;

		case 'n':

			device_name = optarg;

			break;

		case 't':

			trigger_name = optarg;

			datardytrigger = 0;

			trigger_name = strdup(optarg);

			break;

		case 'w':

			errno = 0;

			timedelay = strtoul(optarg, &dummy, 10);

			if (errno)

				return -errno;

			if (errno) {

				ret = -errno;

				goto error;

			}

			break;

		case '?':

			print_usage();

			return -1;

			ret = -1;

			goto error;

		}

	}
@@ -334,14 +400,17 @@ int main(int argc, char **argv) 
	dev_num = find_type_by_name(device_name, "iio:device");

	if (dev_num < 0) {

		fprintf(stderr, "Failed to find the %s\n", device_name);

		return dev_num;

		ret = dev_num;

		goto error;

	}



	printf("iio device number being used is %d\n", dev_num);



	ret = asprintf(&dev_dir_name, "%siio:device%d", iio_dir, dev_num);

	if (ret < 0)

		return -ENOMEM;

	if (ret < 0) {

		ret = -ENOMEM;

		goto error;

	}



	if (!notrigger) {

		if (!trigger_name) {
@@ -354,7 +423,7 @@ int main(int argc, char **argv) 
				       "%s-dev%d", device_name, dev_num);

			if (ret < 0) {

				ret = -ENOMEM;

				goto error_free_dev_dir_name;

				goto error;

			}

		}
@@ -367,7 +436,7 @@ int main(int argc, char **argv) 
				       "%s-trigger", device_name);

			if (ret < 0) {

				ret = -ENOMEM;

				goto error_free_dev_dir_name;

				goto error;

			}

		}
@@ -376,7 +445,7 @@ int main(int argc, char **argv) 
			fprintf(stderr, "Failed to find the trigger %s\n",

				trigger_name);

			ret = trig_num;

			goto error_free_triggername;

			goto error;

		}



		printf("iio trigger number being used is %d\n", trig_num);
@@ -392,7 +461,7 @@ int main(int argc, char **argv) 
	if (ret) {

		fprintf(stderr, "Problem reading scan element information\n"

			"diag %s\n", dev_dir_name);

		goto error_free_triggername;

		goto error;

	}

	if (num_channels && autochannels == AUTOCHANNELS_ENABLED) {

		fprintf(stderr, "Auto-channels selected but some channels "
@@ -407,7 +476,7 @@ int main(int argc, char **argv) 
		ret = enable_disable_all_channels(dev_dir_name, 1);

		if (ret) {

			fprintf(stderr, "Failed to enable all channels\n");

			goto error_free_triggername;

			goto error;

		}



		/* This flags that we need to disable the channels again */
@@ -419,12 +488,12 @@ int main(int argc, char **argv) 
			fprintf(stderr, "Problem reading scan element "

				"information\n"

				"diag %s\n", dev_dir_name);

			goto error_disable_channels;

			goto error;

		}

		if (!num_channels) {

			fprintf(stderr, "Still no channels after "

				"auto-enabling, giving up\n");

			goto error_disable_channels;

			goto error;

		}

	}
@@ -436,7 +505,7 @@ int main(int argc, char **argv) 
			"/*_en or pass -a to autoenable channels and "

			"try again.\n", dev_dir_name);

		ret = -ENOENT;

		goto error_free_triggername;

		goto error;

	}



	/*
@@ -448,7 +517,7 @@ int main(int argc, char **argv) 
		       "%siio:device%d/buffer", iio_dir, dev_num);

	if (ret < 0) {

		ret = -ENOMEM;

		goto error_free_channels;

		goto error;

	}



	if (!notrigger) {
@@ -463,34 +532,34 @@ int main(int argc, char **argv) 
		if (ret < 0) {

			fprintf(stderr,

				"Failed to write current_trigger file\n");

			goto error_free_buf_dir_name;

			goto error;

		}

	}



	/* Setup ring buffer parameters */

	ret = write_sysfs_int("length", buf_dir_name, buf_len);

	if (ret < 0)

		goto error_free_buf_dir_name;

		goto error;



	/* Enable the buffer */

	ret = write_sysfs_int("enable", buf_dir_name, 1);

	if (ret < 0) {

		fprintf(stderr,

			"Failed to enable buffer: %s\n", strerror(-ret));

		goto error_free_buf_dir_name;

		goto error;

	}



	scan_size = size_from_channelarray(channels, num_channels);

	data = malloc(scan_size * buf_len);

	if (!data) {

		ret = -ENOMEM;

		goto error_free_buf_dir_name;

		goto error;

	}



	ret = asprintf(&buffer_access, "/dev/iio:device%d", dev_num);

	if (ret < 0) {

		ret = -ENOMEM;

		goto error_free_data;

		goto error;

	}



	/* Attempt to open non blocking the access dev */
@@ -498,7 +567,7 @@ int main(int argc, char **argv) 
	if (fp == -1) { /* TODO: If it isn't there make the node */

		ret = -errno;

		fprintf(stderr, "Failed to open %s\n", buffer_access);

		goto error_free_buffer_access;

		goto error;

	}



	for (j = 0; j < num_loops; j++) {
@@ -511,7 +580,7 @@ int main(int argc, char **argv) 
			ret = poll(&pfd, 1, -1);

			if (ret < 0) {

				ret = -errno;

				goto error_close_buffer_access;

				goto error;

			} else if (ret == 0) {

				continue;

			}
@@ -536,45 +605,20 @@ int main(int argc, char **argv) 
				     num_channels);

	}



	/* Stop the buffer */

	ret = write_sysfs_int("enable", buf_dir_name, 0);

	if (ret < 0)

		goto error_close_buffer_access;



	if (!notrigger)

		/* Disconnect the trigger - just write a dummy name. */

		ret = write_sysfs_string("trigger/current_trigger",

					 dev_dir_name, "NULL");

		if (ret < 0)

			fprintf(stderr, "Failed to write to %s\n",

				dev_dir_name);

error:

	cleanup();



error_close_buffer_access:

	if (close(fp) == -1)

	if (fp >= 0 && close(fp) == -1)

		perror("Failed to close buffer");



error_free_buffer_access:

	free(buffer_access);

error_free_data:

	free(data);

error_free_buf_dir_name:

	free(buf_dir_name);

error_free_channels:

	for (i = num_channels - 1; i >= 0; i--) {

		free(channels[i].name);

		free(channels[i].generic_name);

	}

	free(channels);

error_free_triggername:

	if (datardytrigger)

	free(trigger_name);

error_disable_channels:

	if (autochannels == AUTOCHANNELS_ACTIVE) {

		ret = enable_disable_all_channels(dev_dir_name, 0);

		if (ret)

			fprintf(stderr, "Failed to disable all channels\n");

	}

error_free_dev_dir_name:

	free(dev_dir_name);



	return ret;

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