[libbluray-devel] [PATCH 1/2] Get the correct java home on macOS

[Marvin Scholz]

On macOS apparently the only way to get the correct
path to the java home for the currently active SDK as
selected by the user is to use the /usr/libexec/java_home
tool.
---

Filip Roséen was able to figure out why it was not working, so this is an
actually working version of the previously submitted patch.
The second patch that loads libjli has no changes.

 src/libbluray/bdj/bdj.c | 64 +++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 64 insertions(+)

diff --git a/src/libbluray/bdj/bdj.c b/src/libbluray/bdj/bdj.c
index d3d4c43..9d0f475 100644
--- a/src/libbluray/bdj/bdj.c
+++ b/src/libbluray/bdj/bdj.c
@@ -38,6 +38,9 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <signal.h>
+#include <limits.h>
+#include <errno.h>
 
 #ifdef _WIN32
 #include <windows.h>
@@ -174,6 +177,53 @@ static inline char *_utf8_to_cp(const char *utf8)
 }
 #endif
 
+#if defined(__APPLE__) && !defined(HAVE_BDJ_J2ME)
+static char *_java_home_macos()
+{
+    FILE *fp;
+    int res = 0;
+    static char initialized = 0;
+    static char result[PATH_MAX];
+
+    if (initialized) {
+        return result;
+    }
+
+    struct sigaction oldsig;
+    sigaction(SIGCHLD, NULL, &oldsig);
+    signal(SIGCHLD, SIG_DFL);
+
+    fp = popen("/usr/libexec/java_home", "r");
+    if (fp == NULL) {
+        BD_DEBUG(DBG_BDJ | DBG_CRIT, "Failed to run 'java_home'\n");
+	goto out;
+    }
+
+    if (fgets(result, PATH_MAX, fp) == NULL) {
+        BD_DEBUG(DBG_BDJ | DBG_CRIT, "Failed to read result from 'java_home'\n");
+	goto out;
+    }
+
+    res = pclose(fp);
+    if (res) {
+        int errsv = errno;
+        BD_DEBUG(DBG_BDJ | DBG_CRIT, "Executing 'java_home' not succesfull. (%i)\n", res);
+        if (res == -1)
+            BD_DEBUG(DBG_BDJ | DBG_CRIT, "pclose() failed: errno %i\n", errsv);
+	goto out;
+    }
+    result[strcspn(result, "\n")] = '\0';
+
+    BD_DEBUG(DBG_BDJ, "Path returned from 'java_home': %s\n", result);
+
+    initialized = 1;
+
+out:
+  sigaction(SIGCHLD, &oldsig, NULL);
+  return initialized ? result : NULL;
+}
+#endif
+
 static void *_jvm_dlopen(const char *java_home, const char *jvm_dir, const char *jvm_lib)
 {
     if (java_home) {
@@ -210,6 +260,11 @@ static void *_load_jvm(const char **p_java_home)
     static const char  jvm_dir[]  = "jre\\bin\\server";
     static const char  jvm_lib[]  = "jvm";
 # else
+#  ifdef __APPLE__
+    static const char *jvm_path[] = {NULL, JDK_HOME};
+    static const char  jvm_dir[]  = "jre/lib/server";
+    static const char  jvm_lib[]  = "libjvm";
+#  else
     static const char *jvm_path[] = {NULL, JDK_HOME,
                                      "/usr/lib/jvm/default-java",
                                      "/usr/lib/jvm/default",
@@ -221,6 +276,7 @@ static void *_load_jvm(const char **p_java_home)
     };
     static const char  jvm_dir[]  = "jre/lib/" JAVA_ARCH "/server";
     static const char  jvm_lib[]  = "libjvm";
+#  endif
 # endif
 #endif
     const char *java_home = NULL;
@@ -241,6 +297,14 @@ static void *_load_jvm(const char **p_java_home)
     }
 #endif
 
+#if defined(__APPLE__) && !defined(HAVE_BDJ_J2ME)
+    java_home = _java_home_macos();
+    if (java_home) {
+        *p_java_home = java_home;
+        return _jvm_dlopen(java_home, jvm_dir, jvm_lib);
+    }
+#endif
+
     BD_DEBUG(DBG_BDJ, "JAVA_HOME not set, trying default locations\n");
 
     /* try our pre-defined locations */
-- 
2.9.3 (Apple Git-75)