examples/acq.c: add better limits checking

A few hard limits were imposed to avoid segmentation faults due to very large integers.

examples/acq.c: add better limits checking
A few hard limits were imposed to avoid segmentation faults due to very large integers.
2f8a4450 · Lucas Russo · 38d1b030 · 2f8a4450
Commit 2f8a4450 authored Jul 11, 2014 by Lucas Russo
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Showing with 23 additions and 6 deletions

acq.c examples/acq.c +23 -6

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--- a/examples/acq.c
+++ b/examples/acq.c
@@ -13,6 +13,10 @@
 #define DFLT_BIND_FOLDER            "/tmp/bpm"

 #define DEFAULT_NUM_SAMPLES         4096
+#define DEFAULT_CHAN_NUM            0
+/* Arbitrary hard limits */
+#define MAX_NUM_SAMPLES             (1 << 28)
+#define MAX_NUM_CHANS               (1 << 8)

 typedef struct _acq_chan_t {
    uint32_t chan;
@@ -78,7 +82,7 @@ int main (int argc, char *argv [])
    char *chan_str = NULL;
    char **str_p = NULL;

-    if (argc < 2) {
+    if (argc < 3) {
        print_help (argv[0]);
        exit (1);
    }
@@ -122,22 +126,35 @@ int main (int argc, char *argv [])
    /* Set default number samples */
    uint32_t num_samples;
    if (num_samples_str == NULL) {
-        fprintf (stderr, "[client:acq]: Set default value to 'num_samples'\n");
+        fprintf (stderr, "[client:acq]: Setting default value to number of samples: %u\n",
+                DEFAULT_NUM_SAMPLES);
        num_samples = DEFAULT_NUM_SAMPLES;
    }
    else {
-        num_samples = (uint32_t) atoi(num_samples_str);
+        num_samples = strtoul (num_samples_str, NULL, 10);
+
+        if (num_samples > MAX_NUM_SAMPLES) {
+            fprintf (stderr, "[client:acq]: Number of samples too big! Defaulting to: %u\n",
+                    MAX_NUM_SAMPLES);
+            num_samples = MAX_NUM_SAMPLES;
+        }
    }
    fprintf (stdout, "[client:acq]: num_samples = %u\n", num_samples);

    /* Set default channel */
    uint32_t chan;
    if (chan_str == NULL) {
-        fprintf (stderr, "[client:acq]: Set default value to 'chan'\n");
-        chan = 0;
+        fprintf (stderr, "[client:acq]: Setting default value to 'chan'\n");
+        chan = DEFAULT_CHAN_NUM;
    }
    else {
-        chan = (uint32_t) atoi(chan_str);
+        chan = strtoul (chan_str, NULL, 10);
+
+        if (chan > MAX_NUM_CHANS) {
+            fprintf (stderr, "[client:acq]: Channel number too big! Defaulting to: %u\n",
+                    MAX_NUM_CHANS);
+            chan = MAX_NUM_CHANS;
+        }
    }
    fprintf (stdout, "[client:acq]: chan = %u\n", chan);