GUAC-236: Add decoder search function.

src/guacenc/image-stream.c

@@ -23,6 +23,7 @@
 #include "config.h"
 #include "image-stream.h"
 #include "jpeg.h"
+#include "log.h"
 #include "png.h"
 
 #ifdef ENABLE_WEBP
@@ -30,6 +31,7 @@
 #endif
 
 #include <stdlib.h>
+#include <string.h>
 
 guacenc_decoder_mapping guacenc_decoder_map[] = {
     {"image/png",  &guacenc_png_decoder},
@@ -40,3 +42,24 @@ guacenc_decoder_mapping guacenc_decoder_map[] = {
     {NULL,         NULL}
 };
 
+guacenc_decoder* guacenc_get_decoder(const char* mimetype) {
+
+    /* Search through mapping for the decoder having given mimetype */
+    guacenc_decoder_mapping* current = guacenc_decoder_map;
+    while (current->mimetype != NULL) {
+
+        /* Return decoder if mimetype matches */
+        if (strcmp(current->mimetype, mimetype) == 0)
+            return current->decoder;
+
+        /* Next candidate decoder */
+        current++;
+
+    }
+
+    /* No such decoder */
+    guacenc_log(GUAC_LOG_WARNING, "Support for \"%s\" not present", mimetype);
+    return NULL;
+
+}
+

src/guacenc/image-stream.h

@@ -193,5 +193,18 @@ typedef struct guacenc_decoder_mapping {
  */
 extern guacenc_decoder_mapping guacenc_decoder_map[];
 
+/**
+ * Returns the decoder associated with the given mimetype. If no such decoder
+ * exists, NULL is returned.
+ *
+ * @param mimetype
+ *     The image mimetype to return the associated decoder of.
+ *
+ * @return
+ *     The decoder associated with the given mimetype, or NULL if no such
+ *     decoder exists.
+ */
+guacenc_decoder* guacenc_get_decoder(const char* mimetype);
+
 #endif