setopt: use the handler table for protocol name to number conversions

This also returns error CURLE_UNSUPPORTED_PROTOCOL rather than
CURLE_BAD_FUNCTION_ARGUMENT when a listed protocol name is not found.

A new schemelen parameter is added to Curl_builtin_scheme() to support
this extended use.

Note that disabled protocols are not recognized anymore.

Tests adapted accordingly.

Closes #9472

tests/data/test1401

@@ -31,6 +31,11 @@ http
  <name>
 --libcurl for GET with various options
  </name>
+<features>
+http
+ftp
+file
+</features>
 <setenv>
 SSL_CERT_FILE=
 </setenv>

tests/libtest/lib1597.c

@@ -30,7 +30,7 @@
 
 struct pair {
   const char *in;
-  CURLcode exp;
+  CURLcode *exp;
 };
 
 int test(char *URL)
@@ -38,27 +38,34 @@ int test(char *URL)
   CURL *curl = NULL;
   int res = 0;
   CURLcode result = CURLE_OK;
+  CURLcode ok = CURLE_OK;
+  CURLcode bad = CURLE_BAD_FUNCTION_ARGUMENT;
+  CURLcode unsup = CURLE_UNSUPPORTED_PROTOCOL;
+  CURLcode httpcode = CURLE_UNSUPPORTED_PROTOCOL;
+  CURLcode httpscode = CURLE_UNSUPPORTED_PROTOCOL;
+  curl_version_info_data *curlinfo;
+  const char *const *proto;
+  char protolist[1024];
+  int n;
   int i;
 
   struct pair prots[] = {
-    {"goobar", CURLE_BAD_FUNCTION_ARGUMENT},
-    {"http ", CURLE_BAD_FUNCTION_ARGUMENT},
-    {" http", CURLE_BAD_FUNCTION_ARGUMENT},
-    {"http", CURLE_OK},
-    {"http,", CURLE_OK},
-    {"https,", CURLE_OK},
-    {"https,http", CURLE_OK},
-    {"http,http", CURLE_OK},
-    {"HTTP,HTTP", CURLE_OK},
-    {",HTTP,HTTP", CURLE_OK},
-    {"http,http,ft", CURLE_BAD_FUNCTION_ARGUMENT},
-    {"", CURLE_BAD_FUNCTION_ARGUMENT},
-    {",,", CURLE_BAD_FUNCTION_ARGUMENT},
-    {"DICT,FILE,FTP,FTPS,GOPHER,GOPHERS,HTTP,HTTPS,IMAP,IMAPS,LDAP,LDAPS,"
-     "POP3,POP3S,RTMP,RTMPE,RTMPS,RTMPT,RTMPTE,RTMPTS,RTSP,SCP,SFTP,SMB,"
-     "SMBS,SMTP,SMTPS,TELNET,TFTP", CURLE_OK},
-    {"all", CURLE_OK},
-    {NULL, CURLE_OK},
+    {"goobar", &unsup},
+    {"http ", &unsup},
+    {" http", &unsup},
+    {"http", &httpcode},
+    {"http,", &httpcode},
+    {"https,", &httpscode},
+    {"https,http", &httpscode},
+    {"http,http", &httpcode},
+    {"HTTP,HTTP", &httpcode},
+    {",HTTP,HTTP", &httpcode},
+    {"http,http,ft", &unsup},
+    {"", &bad},
+    {",,", &bad},
+    {protolist, &ok},
+    {"all", &ok},
+    {NULL, NULL},
   };
   (void)URL;
 
@@ -66,9 +73,32 @@ int test(char *URL)
 
   easy_init(curl);
 
+  /* Get enabled protocols.*/
+  curlinfo = curl_version_info(CURLVERSION_NOW);
+  if(!curlinfo) {
+    fputs("curl_version_info failed\n", stderr);
+    res = (int) TEST_ERR_FAILURE;
+    goto test_cleanup;
+  }
+
+  n = 0;
+  for(proto = curlinfo->protocols; *proto; proto++) {
+    if((size_t) n >= sizeof(protolist)) {
+      puts("protolist buffer too small\n");
+      res = (int) TEST_ERR_FAILURE;
+      goto test_cleanup;
+    }
+    n += msnprintf(protolist + n, sizeof(protolist) - n, ",%s", *proto);
+    if(curl_strequal(*proto, "http"))
+      httpcode = CURLE_OK;
+    if(curl_strequal(*proto, "https"))
+      httpscode = CURLE_OK;
+  }
+
+  /* Run the tests. */
   for(i = 0; prots[i].in; i++) {
     result = curl_easy_setopt(curl, CURLOPT_PROTOCOLS_STR, prots[i].in);
-    if(result != prots[i].exp) {
+    if(result != *prots[i].exp) {
       printf("unexpectedly '%s' returned %u\n",
              prots[i].in, result);
       break;

tests/libtest/lib1911.c

@@ -79,6 +79,7 @@ int test(char *URL)
       case CURLE_BAD_FUNCTION_ARGUMENT: /* the most normal */
       case CURLE_UNKNOWN_OPTION: /* left out from the build */
       case CURLE_NOT_BUILT_IN: /* not supported */
+      case CURLE_UNSUPPORTED_PROTOCOL: /* detected by protocol2num() */
         break;
       default:
         /* all other return codes are unexpected */