input/trace32_ad: silence format match logging, improve robustness

There is not much point in log messages about format mismatch in the
auto detect phase, where each module gets queried in turn and most are
supposed to not match.

Do not print non-printable characters in log messages. Those could occur
in the format detection phase, or in the regular processing of input
files that either are unexpected or invalid (or is there a binary header
format variant even?).

diff --git a/src/input/trace32_ad.c b/src/input/trace32_ad.c
index 046cb53bef64cf2f258b71776118e623952b1ede..1f69028887b09a297bec438174430a205d94aa5c 100644 (file)
--- a/src/input/trace32_ad.c
+++ b/src/input/trace32_ad.c
@@ -98,6 +98,29 @@ struct context {
 static int process_header(GString *buf, struct context *inc);
 static void create_channels(struct sr_input *in);
 
+/* Transform non-printable chars to '\xNN' presentation. */
+static char *printable_name(const char *name)
+{
+       size_t l, i;
+       char *s, *p;
+
+       if (!name)
+               return NULL;
+       l = strlen(name);
+       s = g_malloc0(l * strlen("\\x00") + 1);
+       for (p = s, i = 0; i < l; i++) {
+               if (g_ascii_isprint(name[i])) {
+                       *p++ = name[i];
+               } else {
+                       snprintf(p, 5, "\\x%05x", name[i]);
+                       p += strlen("\\x00");
+               }
+       }
+       *p = '\0';
+
+       return s;
+}
+
 static char get_pod_name_from_id(int id)
 {
        switch (id) {
@@ -174,6 +197,7 @@ static int format_match(GHashTable *metadata, unsigned int *confidence)
 static int process_header(GString *buf, struct context *inc)
 {
        char *format_name, *format_name_sig;
+       char *p;
        int i, record_size, device_id;
 
        /*
@@ -195,7 +219,13 @@ static int process_header(GString *buf, struct context *inc)
         * 78-79 (0x4E-4F) ??
         */
 
-       /* Note: inc is off-limits until we check whether it's a valid pointer. */
+       /*
+        * Note: The routine is called from different contexts. Either
+        * to auto-detect the file format (format_match(), 'inc' is NULL),
+        * or to process the data during acquisition (receive(), 'inc'
+        * is a valid pointer). This header parse routine shall gracefully
+        * deal with unexpected or incorrect input data.
+        */
 
        format_name = g_strndup(buf->str, 32);
 
@@ -221,20 +251,18 @@ static int process_header(GString *buf, struct context *inc)
                g_free(format_name);
                if (inc)
                        sr_err("This format isn't implemented yet, aborting.");
-               else
-                       sr_dbg("Not a supported trace32 input file.");
                return SR_ERR;
        } else {
                g_free(format_name_sig);
                g_free(format_name);
                if (inc)
                        sr_err("Don't know this file format, aborting.");
-               else
-                       sr_dbg("Not a trace32 input file.");
                return SR_ERR;
        }
 
-       sr_dbg("File says it's \"%s\"", format_name);
+       p = printable_name(format_name);
+       sr_dbg("File says it's \"%s\"", p);
+       g_free(p);
 
        record_size = R8(buf->str + 56);
        device_id = 0;