Add API call to determine if format capability structure is "empty".

Empty here means that there are no formats in the format_cap structure
or the only format in it is the "none" format.

I've added calls to check the emptiness of a format_cap in a few places
in order to short-circuit operations that would otherwise be pointless
as well as to prevent some assertions from being triggered in cases
where channels with no formats are used.

git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/13@423414 65c4cc65-6c06-0410-ace0-fbb531ad65f3

diff --git a/include/asterisk/format_cap.h b/include/asterisk/format_cap.h
index f7d33fccda72e1d6f1d1ce29dcf3257153938726..94e81f869e9b1d6c00ebc41d3e151ebedf65c016 100644 (file)
--- a/include/asterisk/format_cap.h
+++ b/include/asterisk/format_cap.h
@@ -321,4 +321,13 @@ int ast_format_cap_has_type(const struct ast_format_cap *cap, enum ast_media_typ
  */
 const char *ast_format_cap_get_names(struct ast_format_cap *cap, struct ast_str **buf);
 
+/*!
+ * \brief Determine if a format cap has no formats in it.
+ *
+ * \param cap The format cap to check for emptiness
+ * \retval 1 The format cap has zero formats or only ast_format_none
+ * \retval 0 The format cap has at least one format
+ */
+int ast_format_cap_empty(struct ast_format_cap *cap);
+
 #endif /* _AST_FORMAT_CAP_H */

diff --git a/main/channel.c b/main/channel.c
index 4595b5944c0c1fca65ac59399165bf4aebded545..477bc815b25cf7c4057547de283edc36caa7a1b9 100644 (file)
--- a/main/channel.c
+++ b/main/channel.c
@@ -5327,6 +5327,11 @@ static int set_format(struct ast_channel *chan, struct ast_format_cap *cap_set,
        ast_assert(rawformat != NULL);
 
        cap_native = ast_channel_nativeformats(chan);
+       if (ast_format_cap_empty(cap_native)) {
+               ast_log(LOG_ERROR, "Unable to set format because channel %s supports no formats\n",
+                               ast_channel_name(chan));
+               return -1;
+       }
 
        /* Find a translation path from the native format to one of the desired formats */
        if (!direction) {

diff --git a/main/format_cap.c b/main/format_cap.c
index 65e469fc16a123037357498a412f6418dda8a510..364c924bfd116f7bcf2edb88b13854e3befc8c9d 100644 (file)
--- a/main/format_cap.c
+++ b/main/format_cap.c
@@ -700,3 +700,18 @@ const char *ast_format_cap_get_names(struct ast_format_cap *cap, struct ast_str
 
        return ast_str_buffer(*buf);
 }
+
+int ast_format_cap_empty(struct ast_format_cap *cap)
+{
+       int count = ast_format_cap_count(cap);
+
+       if (count > 1) {
+               return 0;
+       }
+
+       if (count == 0 || AST_VECTOR_GET(&cap->preference_order, 0)->format == ast_format_none) {
+               return 1;
+       }
+
+       return 0;
+}

diff --git a/main/translate.c b/main/translate.c
index 0696f5d836d6a1154ec43a903e1ab9b4fad3209c..2778ebccf6b493e34bdb0d3337bbceeecc0b7886 100644 (file)
--- a/main/translate.c
+++ b/main/translate.c
@@ -1276,6 +1276,11 @@ int ast_translator_best_choice(struct ast_format_cap *dst_cap,
        int i;
        int j;
 
+       if (ast_format_cap_empty(dst_cap) || ast_format_cap_empty(src_cap)) {
+               ast_log(LOG_ERROR, "Cannot determine best translation path since one capability supports no formats\n");
+               return -1;
+       }
+
        if (!(joint_cap = ast_format_cap_alloc(AST_FORMAT_CAP_FLAG_DEFAULT))) {
                return -1;
        }