Use WAV file sample rate unless user explicitly set samprate

Fixes issue where WAV file sample rates were ignored because the check
for 'samprate == 0' always failed (samprate defaults to 16000).

Now checks if -samprate was actually passed on the command line. If not,
uses the WAV file's sample rate. If user explicitly set it, respects
their choice.

This allows WAV files with any sample rate (8kHz, 24kHz, 32kHz, 48kHz,
etc.) to be processed correctly without requiring users to manually
specify -samprate.

Author: lenzo-ka

src/util/soundfiles.c

@@ -43,6 +43,7 @@
 #include <pocketsphinx.h>
 #include "util/byteorder.h"
 #include "util/ckd_alloc.h"
+#include "util/cmd_ln.h"
 
 #define TRY_FREAD(ptr, size, nmemb, stream)                             \
     if (fread(ptr, size, nmemb, stream) != (nmemb)) {                   \
@@ -51,6 +52,22 @@
         goto error_out;                                                 \
     }
 
+static int
+arg_was_set(ps_config_t *config, const char *name)
+{
+    uint32 i;
+    cmd_ln_t *cmdln = (cmd_ln_t *)config;
+    for (i = 0; i < cmdln->f_argc; i++) {
+        if (cmdln->f_argv[i] && cmdln->f_argv[i][0] == '-') {
+            const char *arg = cmdln->f_argv[i] + 1;
+            if (*arg == '-') arg++;
+            if (0 == strcmp(arg, name))
+                return 1;
+        }
+    }
+    return 0;
+}
+
 int
 ps_config_soundfile(ps_config_t *config, FILE *infh, const char *file)
 {
@@ -154,9 +171,9 @@ ps_config_wavfile(ps_config_t *config, FILE *infh, const char *file)
     /* Sampling rate (finally!) */
     TRY_FREAD(&intval, 4, 1, infh);
     SWAP_LE_32(&intval);
-    if (ps_config_int(config, "samprate") == 0)
+    if (!arg_was_set(config, "samprate")) {
         ps_config_set_int(config, "samprate", intval);
-    else if (ps_config_int(config, "samprate") != intval) {
+    } else if (ps_config_int(config, "samprate") != intval) {
         E_WARN("WAVE file sampling rate %d != samprate %d\n",
                intval, ps_config_int(config, "samprate"));
     }