curl: add --remove-on-error

If a transfer returns an error, using this option makes curl remove the
leftover downloded (partial) local file before exiting.

Added test 376 to verify

Closes #8503

src/tool_cfgable.h

@@ -294,6 +294,8 @@ struct OperationConfig {
   struct OperationConfig *prev;
   struct OperationConfig *next;   /* Always last in the struct */
   struct State state;             /* for create_transfer() */
+  bool rm_partial;                /* on error, remove partially written output
+                                     files */
 };
 
 struct GlobalConfig {

src/tool_getparam.c

@@ -284,6 +284,7 @@ static const struct LongShort aliases[]= {
   {"fb", "styled-output",            ARG_BOOL},
   {"fc", "mail-rcpt-allowfails",     ARG_BOOL},
   {"fd", "fail-with-body",           ARG_BOOL},
+  {"fe", "remove-on-error",          ARG_BOOL},
   {"F",  "form",                     ARG_STRING},
   {"Fs", "form-string",              ARG_STRING},
   {"g",  "globoff",                  ARG_BOOL},
@@ -1830,7 +1831,10 @@ ParameterError getparameter(const char *flag, /* f or -long-flag */
       case 'd': /* --fail-with-body */
         config->failwithbody = toggle;
         break;
-      default: /* --fail (hard on errors)  */
+      case 'e': /* --remove-on-error */
+        config->rm_partial = toggle;
+        break;
+       default: /* --fail (hard on errors)  */
         config->failonerror = toggle;
         break;
       }

src/tool_listhelp.c

@@ -574,6 +574,9 @@ const struct helptxt helptext[] = {
   {"-R, --remote-time",
    "Set the remote file's time on the local output",
    CURLHELP_OUTPUT},
+  {"    --remove-on-error",
+   "Remove output file on errors",
+   CURLHELP_CURL},
   {"-X, --request <method>",
    "Specify request method to use",
    CURLHELP_CONNECTION},

src/tool_operate.c

@@ -595,6 +595,10 @@ static CURLcode post_per_transfer(struct GlobalConfig *global,
       if(global->showerror)
         fprintf(global->errors, "curl: (%d) Failed writing body\n", result);
     }
+    if(result && config->rm_partial) {
+      notef(global, "Removing output file: %s", per->outfile);
+      unlink(per->outfile);
+    }
   }
 
   /* File time can only be set _after_ the file has been closed */