[DO-971] ffmpeg recipe with requirements (!9)

Co-authored-by: aleksandr.vodyanov <aleksandr.vodyanov@avroid.tech>
Reviewed-on: https://git.avroid.tech/Conan/conan_build/pulls/9

recipes/libiconv/all/test_package/test_package.c

@@ -0,0 +1,50 @@
+#include <stddef.h>
+#include <stdio.h>
+#include <stdlib.h> //for EXIT_FAILURE
+#include <locale.h>
+
+#if _MSC_VER && _MSC_VER < 1600
+typedef unsigned __int32 uint32_t;
+#else
+#include <stdint.h>
+#endif
+
+#include "iconv.h"
+#include "libcharset.h"
+
+int main()
+{
+    // Test libiconv
+    char in_bytes[4] = {'c', 'i', 'a', 'o'};
+    char *in_buffer = (char *)&in_bytes;
+    size_t in_bytes_left = sizeof(char) * 4;
+    uint32_t ou_bytes[4] = {(uint32_t)-1, (uint32_t)-1, (uint32_t)-1, (uint32_t)-1};
+    size_t ou_bytes_left = sizeof(uint32_t) * 4;
+    char *ou_buffer = (char *)&ou_bytes;
+    iconv_t context;
+    size_t rv;
+
+    context = iconv_open("UCS-4-INTERNAL", "US-ASCII");
+    if ((iconv_t)(-1) == context)
+    {
+        fprintf(stderr, "iconv_open failed\n");
+        return EXIT_FAILURE;
+    }
+
+    rv = iconv(context, &in_buffer, &in_bytes_left, &ou_buffer, &ou_bytes_left);
+    if ((size_t)(-1) == rv)
+    {
+        fprintf(stderr, "icon failed\n");
+        return EXIT_FAILURE;
+    }
+
+    printf("retval libiconv: %lu %u %u %u %u\n", rv, ou_bytes[0], ou_bytes[1], ou_bytes[2], ou_bytes[3]);
+
+    iconv_close(context);
+
+    // Test libcharset
+    setlocale(LC_ALL, "");
+    printf("retval libcharset: %s\n", locale_charset());
+
+    return EXIT_SUCCESS;
+}