Added auto resolve of symbolic links (for homebrew)

Author: cpurdy

javatools_launcher/build/exe/macos_launcher

@@ -30,7 +30,7 @@ int main(int argc, const char* argv[])
     const char* execPath = findLauncherPath();
 
     // next, load the optional config for the executable
-    const char* execDir  = extractDir(execPath);
+    const char* execDir  = extractDir(resolveLinks(execPath));
     const char* execFile = removeExtension(extractFile(execPath));
     const char* cfgPath  = buildPath(execDir, withExtension(execFile, ".cfg"));
     const char* cfg      = readFile(cfgPath);
@@ -54,6 +54,9 @@ static int   garbageCount = 0;
  */
 static void init()
     {
+    // for any debug output, stdout must not be buffered
+    setbuf(stdout, NULL);
+
     memset(garbage, 0, MAX_GARBAGE * sizeof(void*));
     }
 

javatools_launcher/src/main/c/launcher.c

@@ -23,6 +23,15 @@
  */
 extern const char* findLauncherPath();
 
+/**
+ * If the file is a link, follow the link until a real file is found.
+ *
+ * @param path  the path to a file that may be a link
+ *
+ * @return the file at the end of the linked list of links
+ */
+extern const char* resolveLinks(const char* path);
+
 /**
  * Execute the JVM against the specified JAR.
  *

javatools_launcher/src/main/c/os_specific.h

@@ -1,3 +1,4 @@
+#include <limits.h>
 #include <stdio.h>
 #include <string.h>
 #include <stdlib.h>
@@ -9,6 +10,23 @@
 
 // shared code for Linux and macos implementations
 
+const char* resolveLinks(const char* path)
+    {
+    char ach[PATH_MAX];
+    if (!realpath(path, ach))
+        {
+        abortLaunch("Unresolvable link");
+        }
+
+    if (strcmp(path, ach) == 0)
+        {
+        return path;
+        }
+
+    char* result = allocBuffer(strlen(ach)+1);
+    strcpy(result, ach);
+    return result;
+    }
 
 void execJava(const char* javaPath,
               const char* javaOpts,