Fails to build with pocketsphinx 5

[Samuel Thibault]

Summary of the bug:
How to reproduce:
After having installed pocketsphinx version 5.0.2 (from ​https://github.com/cmusphinx/pocketsphinx/), ffmpeg fails to build:

src/libavfilter/af_asr.c:42:5: error: unknown type name 'cmd_ln_t'
   42 |     cmd_ln_t *config;
      |     ^~~~~~~~
src/libavfilter/af_asr.c: In function 'asr_init':
src/libavfilter/af_asr.c:110:17: error: implicit declaration of function 'cmd_ln_parse_r' [-Werror=implicit-function-declaration]
  110 |     s->config = cmd_ln_parse_r(NULL, ps_args(), 14, (char **)argv, 0);
      |                 ^~~~~~~~~~~~~~
src/libavfilter/af_asr.c:110:15: warning: assignment to 'int *' from 'int' makes pointer from integer without a cast [-Wint-conversion]
  110 |     s->config = cmd_ln_parse_r(NULL, ps_args(), 14, (char **)argv, 0);
      |               ^
src/libavfilter/af_asr.c:115:29: warning: passing argument 1 of 'ps_default_search_args' from incompatible pointer type [-Wincompatible-pointer-types]
  115 |     ps_default_search_args(s->config);
      |                            ~^~~~~~~~
      |                             |
      |                             int *
In file included from src/libavfilter/af_asr.c:21:
/usr/include/pocketsphinx.h:465:42: note: expected 'ps_config_t *' {aka 'struct cmd_ln_s *'} but argument is of type 'int *'
  465 | void ps_default_search_args(ps_config_t *config);
      |                             ~~~~~~~~~~~~~^~~~~~
src/libavfilter/af_asr.c:116:22: warning: passing argument 1 of 'ps_init' from incompatible pointer type [-Wincompatible-pointer-types]
  116 |     s->ps = ps_init(s->config);
      |                     ~^~~~~~~~
      |                      |
      |                      int *
/usr/include/pocketsphinx.h:498:36: note: expected 'ps_config_t *' {aka 'struct cmd_ln_s *'} but argument is of type 'int *'
  498 | ps_decoder_t *ps_init(ps_config_t *config);
      |                       ~~~~~~~~~~~~~^~~~~~
src/libavfilter/af_asr.c: In function 'asr_uninit':
src/libavfilter/af_asr.c:148:5: error: implicit declaration of function 'cmd_ln_free_r' [-Werror=implicit-function-declaration]
  148 |     cmd_ln_free_r(s->config);
      |     ^~~~~~~~~~~~~

This is apparently an intentional API break of pocketsphinx: from pocketsphinx.h:

 * @section faq_sec Frequently Asked Questions
 *
 * @subsection faq_api My code no longer compiles! Why?
 *
 * Some APIs were intentionally broken by the 5.0.0 release.  The most
 * likely culprit here is the configuration API, where the old
 * "options" which started with a `-` are now "parameters" which do
 * not, and instead of a `cmd_ln_t` it is now a `ps_config_t`.  There
 * is no backward compatibility, you have to change your code
 * manually.  This is straightforward for the most part.  For example,
 * instead of writing:
 *
 *     cmdln = cmd_ln_init(NULL, "-samprate", "16000", NULL);
 *     cmd_ln_set_int32_r(NULL, "-maxwpf", 40);
 *
 * You should write:
 *
 *     config = ps_config_init(NULL);
 *     ps_config_set_int(config, "samprate", 16000);
 *     ps_config_set_int(config, "maxwpf", 40);

So this needs to be done in ffmpeg.

[aredigg]

Here is a simple diff, but should be tested more

diff --git a/libavfilter/af_asr.c b/libavfilter/af_asr.c
index 8e8eeb19a7..bba793cfb5 100644
--- a/libavfilter/af_asr.c
+++ b/libavfilter/af_asr.c
@@ -41,7 +41,7 @@ typedef struct ASRContext {
     char *logfn;
 
     ps_decoder_t *ps;
-    cmd_ln_t *config;
+    ps_config_t *config;
 
     int utt_started;
 } ASRContext;
@@ -100,16 +100,16 @@ static av_cold int asr_init(AVFilterContext *ctx)
     ASRContext *s = ctx->priv;
     const float frate = s->rate;
     char *rate = av_asprintf("%f", frate);
-    const char *argv[] = { "-logfn",    s->logfn,
-                           "-hmm",      s->hmm,
-                           "-lm",       s->lm,
-                           "-lmctl",    s->lmctl,
-                           "-lmname",   s->lmname,
-                           "-dict",     s->dict,
-                           "-samprate", rate,
-                           NULL };
-
-    s->config = cmd_ln_parse_r(NULL, ps_args(), 14, (char **)argv, 0);
+
+    s->config = ps_config_init(NULL);
+    ps_config_set_str(s->config, "logfn", s->logfn);
+    ps_config_set_str(s->config, "hmm", s->hmm);
+    ps_config_set_str(s->config, "lm", s->lm);
+    ps_config_set_str(s->config, "lmctl", s->lmctl);
+    ps_config_set_str(s->config, "lmname", s->lmname);
+    ps_config_set_str(s->config, "dict", s->dict);
+    ps_config_set_str(s->config, "samprate", rate);
+
     av_free(rate);
     if (!s->config)
         return AVERROR(ENOMEM);
@@ -160,7 +160,7 @@ static av_cold void asr_uninit(AVFilterContext *ctx)
 
     ps_free(s->ps);
     s->ps = NULL;
-    cmd_ln_free_r(s->config);
+    ps_config_free(s->config);
     s->config = NULL;
 }