arch/all-android/bootstrap/kickstart.c

   1 /*
   2     Copyright © 1995-2016, The AROS Development Team. All rights reserved.
   3     $Id$
   4 */
   5
   6 #include <sys/wait.h>
   7
   8 #include <errno.h>
   9 #include <signal.h>
  10 #include <stdio.h>
  11 #include <stdlib.h>
  12 #include <unistd.h>
  13
  14 /* These macros are defined in both UNIX and AROS headers. Get rid of warnings. */
  15 #undef __pure
  16 #undef __const
  17 #undef __pure2
  18 #undef __deprecated
  19
  20 #include <aros/kernel.h>
  21 #include <runtime.h>
  22
  23 #include "android.h"
  24 #include "kickstart.h"
  25 #include "platform.h"
  26
  27 #define D(x) x
  28
  29 /*
  30  * This is Android-hosted kicker.
  31  * Android environment is the most alien one to AROS. It's proved to be impossible
  32  * to run AROS inside JNI because AROS task switching is no friend to threads.
  33  * However it's possible to run AROS as a separate process. This way it will be
  34  * completely detached and live on its own.
  35  *
  36  * The bootstrap itself still runs in JVM context, this makes it easier to
  37  * implement DisplayError().
  38  */
  39
  40 /* Interface with the display driver */
  41 int DisplayPipe;
  42 int InputPipe;
  43
  44 /* This is where we remember our data */
  45 static int (*EntryPoint)() = NULL;
  46 static struct TagItem *BootMsg = NULL;
  47 static pid_t AROS_pid = -1;
  48
  49 /*
  50  * Our SIGCHLD handler.
  51  * It will notify Java side when AROS process exits. Additionally it will free allocated memory
  52  * before performing a cold reboot.
  53  */
  54 static void childHandler(int sig)
  55 {
  56     int i;
  57
  58     wait(&i);
  59
  60     if (WIFEXITED(i))
  61     {
  62         int code = WEXITSTATUS(i);
  63
  64         D(kprintf("[Bootstrap] AROS process exited with code 0x%08X\n", code));
  65
  66         /*
  67          * If the requested action is not a warm reboot, free all the RAM.
  68          * On cold reboot we will reload the kickstart from scratch.
  69          */
  70         if (code != STATUS_WARM_REBOOT)
  71             Host_FreeMem();
  72
  73         /* Let the Java part to do the work */
  74         (*Java_Env)->CallVoidMethod(Java_Env, Java_Object, HandleExit_mid, WEXITSTATUS(i));
  75     }
  76     else
  77     {
  78         DisplayError("AROS process terminated, status 0x%08X\n", i);
  79     }
  80 }
  81
  82 /*
  83  * Just remember arguments and return with zero returncode.
  84  * This will signal to Java side that preparation (Load() method)
  85  * completed successfully. Next Java side can execute Kick() method
  86  * in order to actually run AROS.
  87  * This separation helps to implement warm restart. Kick() can be executed
  88  * multiple times.
  89  */
  90 int kick(int (*addr)(), struct TagItem *msg)
  91 {
  92     EntryPoint = addr;
  93     BootMsg    = msg;
  94
  95     return 0;
  96 }
  97
  98 /*
  99  * The actual kicker.
 100  * Similar to generic UNIX one, but uses SIGCHILD handler instead of waitpid()
 101  * in order to detect when AROS exits.
 102  * When this method successfully exits, a display pipe server is run on Java side.
 103  */
 104 int Java_org_aros_bootstrap_AROSBootstrap_Kick(JNIEnv* env, jobject this, jobject readfd, jobject writefd)
 105 {
 106     struct sigaction sa;
 107     int displaypipe[2];
 108     int inputpipe[2];
 109     int i;
 110     jclass *class_fdesc = (*env)->GetObjectClass(env, readfd);
 111     /*
 112      * In Sun JVM this is 'fd' field, in Android it's 'descriptor'.
 113      * This is the only place which can be considered a hack. I hope Android guys
 114      * won't change this.
 115      */
 116     jfieldID field_fd = (*env)->GetFieldID(env, class_fdesc, "descriptor", "I");
 117
 118     if (!field_fd)
 119     {
 120         DisplayError("Failed to set up pipe descriptor objects");
 121         return -1;
 122     }
 123
 124     sigemptyset(&sa.sa_mask);
 125     sa.sa_flags    = SA_RESTART;
 126     sa.sa_restorer = NULL;
 127     sa.sa_handler  = childHandler;
 128
 129     sigaction(SIGCHLD, &sa, NULL);
 130
 131     if (pipe(displaypipe))
 132     {
 133         DisplayError("Failed to create display pipe: %s", strerror(errno));
 134         return -1;
 135     }
 136
 137     if (pipe(inputpipe))
 138     {
 139         close(displaypipe[0]);
 140         close(displaypipe[1]);
 141
 142         DisplayError("Failed to create input pipe: %s", strerror(errno));
 143         return -1;
 144     }
 145
 146     D(kprintf("[Bootstrap] Launching kickstart...\n"));
 147     AROS_pid = fork();
 148
 149     switch (AROS_pid)
 150     {
 151     case -1:
 152         close(displaypipe[0]);
 153         close(displaypipe[1]);
 154         close(inputpipe[0]);
 155         close(inputpipe[1]);
 156
 157         DisplayError("Failed to run kickstart!");
 158         return -1;
 159
 160     case 0:
 161         /* Set up client side of pipes */
 162         DisplayPipe = displaypipe[1];
 163         InputPipe   = inputpipe[0];
 164         close(displaypipe[0]);
 165         close(inputpipe[1]);
 166
 167         D(kprintf("[Bootstrap] entering kernel at %p...\n", EntryPoint));
 168         i = EntryPoint(BootMsg, AROS_BOOT_MAGIC);
 169         exit(i);
 170     }
 171
 172     D(kprintf("[Bootstrap] AROS PID %d, bootstrap PID %d\n", AROS_pid, getpid()));
 173
 174     /* Set up server side of pipes */
 175     (*env)->SetIntField(env, readfd, field_fd, displaypipe[0]);
 176     (*env)->SetIntField(env, writefd, field_fd, inputpipe[1]);
 177     close(displaypipe[1]);
 178     close(inputpipe[0]);
 179
 180     /* Return to JVM with success indication */
 181     return 0;
 182 }
 183
 184 /* A small method which allows display server to send signals to AROS process */
 185 int Java_org_aros_bootstrap_AROSBootstrap_Kill(JNIEnv* env, jobject this, jint signal)
 186 {
 187     int res = kill(AROS_pid, signal);
 188
 189     D(kprintf("[Bootstrap] kill(%d, %d) returned %d, errno %d\n", AROS_pid, signal, res, errno));
 190     return res;
 191 }