Check for presence of NetDisk and Marinetti, and bail out if they're missing.

diskbrowser.c

@@ -14,6 +14,8 @@
 #include <gsos.h>
 #include <orca.h>
 #include <finder.h>
+#include <tcpip.h>
+#include "mounturl.h"
 
 static char menuTitle[] = "\pArchive.org Disk Browser\xC9";
 static char windowTitle[] = "\p  Archive.org Disk Browser  ";
@@ -59,6 +61,8 @@ struct diskListEntry {
 
 struct diskListEntry diskList[DISK_LIST_LENGTH];
 
+static struct MountURLRec mountURLRec = {sizeof(struct MountURLRec)};
+
 /* Record about our system window, to support processing by Desk Manager. */
 /* See Prog. Ref. for System 6.0, page 20. */
 static NDASysWindRecord sysWindRecord;
@@ -365,6 +369,21 @@ static pascal Word requestProc(Word reqCode, Long dataIn, void *dataOut) {
 #pragma toolparms 0
 #pragma databank 0
 
+boolean NetDiskPresent(void)
+{
+    mountURLRec.result = NETDISK_NOT_PRESENT;
+    mountURLRec.url = "";
+    mountURLRec.flags = flgUseCache;
+
+    SendRequest(MountURL, sendToName|stopAfterOne, (Long)NETDISK_REQUEST_NAME,
+                (Long)&mountURLRec, NULL);
+
+    if (mountURLRec.result == NETDISK_NOT_PRESENT) {
+        return false;
+    }
+
+    return true;
+}
 
 int main(void) {
     myUserID = MMStartUp(); //userid() & 0xF0FF;
@@ -373,5 +392,10 @@ int main(void) {
     ResourceStartUp(myUserID);
     SetCurResourceApp(origResourceApp);
 
+    /* Bail out if NetDisk or Marinetti is not present */
+    if (!NetDiskPresent() || !TCPIPStatus() || toolerror()) {
+        return 1;
+    }
+
     AcceptRequests(diskbrowserRequestName, myUserID, &requestProc);
 }

mounturl.h

@@ -0,0 +1,31 @@
+#ifndef MOUNTURL_H
+#define MOUNTURL_H
+
+#include "netdiskerror.h"
+
+/* Custom DControl code and request code for MountURL operation */
+#define MountURL 0x8080
+
+#define NETDISK_REQUEST_NAME "\pSTH~NetDisk~"
+
+/* Bits in flags */
+#define flgUseCache 0x0001
+
+enum DiskImageFormat {
+    formatAutoDetect = 0,
+    format2mg,
+    formatRaw,
+    formatDOSOrder,
+    formatDiskCopy42
+};
+
+struct MountURLRec {
+    Word byteCount;
+    enum NetDiskError result; /* output value */
+    char *url; /* C-string; will be modified */
+    Word flags;
+    enum DiskImageFormat format; /* input/output value */
+    Word devNum; /* output value: device number */
+};
+
+#endif

netdiskerror.h

@@ -0,0 +1,53 @@
+#ifndef NETDISKERROR_H
+#define NETDISKERROR_H
+
+enum NetDiskError {
+    OPERATION_SUCCESSFUL = 0,
+    
+    NETDISK_NOT_PRESENT = 100,
+    DISK_ALREADY_MOUNTED,
+    NO_DIBS_AVAILABLE,
+    OUT_OF_MEMORY,
+
+    /* SetURL errors */
+    URL_TOO_LONG = 200,
+    INVALID_CHARACTER_IN_URL,
+    BAD_URL_SYNTAX,
+    UNSUPPORTED_URL_SCHEME,
+    AUTHENTICATION_NOT_SUPPORTED,
+    FRAGMENT_NOT_SUPPORTED,
+    INVALID_PORT_NUMBER,
+    NO_HOST_SPECIFIED,
+    IPV6_NOT_SUPPORTED,
+    HOSTNAME_TOO_LONG,
+    NAME_LOOKUP_FAILED,
+    
+    /* StartTCPConnection and DoHTTPRequest errors */
+    NETWORK_ERROR = 300,
+    NO_RESPONSE,
+    INVALID_RESPONSE,
+    EXCESSIVE_REDIRECTS,
+    UNSUPPORTED_RESPONSE,
+    UNSUPPORTED_HEADER_VALUE,
+    REDIRECT_ERROR,
+    NOT_DESIRED_CONTENT,
+    DIFFERENT_LENGTH,
+    
+    /* Error values of 4xx and 5xx mean we got the corresponding HTTP error */
+    HTTP_ERROR = 400,
+    
+    /* File format errors */
+    UNSUPPORTED_2IMG_FILE = 600,
+    NOT_MULTIPLE_OF_BLOCK_SIZE,
+    NOT_SPECIFIED_IMAGE_TYPE
+    
+};
+
+
+/*
+ * Return a string describing the error.  It may contain the substitution
+ * string "*0", which should be replaced by the error number.
+ */
+char *ErrorString(enum NetDiskError err);
+
+#endif