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: Crestez Dan Leonard <leonard.cres...@intel.com> --- Changes since v2: Initialize data to NULL to prevent crash on free. tools/iio/generic_buffer.c | 172 ++++++++++++++++++++++++++++----------------- 1 file changed, 108 insertions(+), 64 deletions(-) diff --git a/tools/iio/generic_buffer.c b/tools/iio/generic_buffer.c index 2429c78..972f400 100644 --- a/tools/iio/generic_buffer.c +++ b/tools/iio/generic_buffer.c @@ -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(trigger_name); free(dev_dir_name); return ret; -- 2.5.5