Reboot when trampoline can't mount /data on second boot

* On second boot, we have secondary ROM's kernel running and don't
  want to boot the primary ROM with it.

lib/mrom_data.c

@@ -42,3 +42,48 @@ const char *mrom_dir(void)
 {
     return multirom_dir;
 }
+
+int mrom_is_second_boot(void)
+{
+    int i;
+    int res = 0;
+    FILE *f = NULL;
+    char buff[2048];
+
+    static const char *kmsg_paths[] = {
+        "/proc/last_kmsg",
+        "/sys/fs/pstore/console-ramoops",
+        NULL,
+    };
+
+    f = fopen("/proc/cmdline", "re");
+    if(f)
+    {
+        if(fgets(buff, sizeof(buff), f) && strstr(buff, "mrom_kexecd=1"))
+        {
+            res = 1;
+            goto exit;
+        }
+
+        fclose(f);
+    }
+
+    for(i = 0; !f && kmsg_paths[i]; ++i)
+        f = fopen(kmsg_paths[i], "re");
+
+    if(!f)
+        return 0;
+
+    while(fgets(buff, sizeof(buff), f))
+    {
+        if(strstr(buff, SECOND_BOOT_KMESG))
+        {
+            res = 1;
+            goto exit;
+        }
+    }
+
+exit:
+    fclose(f);
+    return res;
+}

lib/mrom_data.h

@@ -18,10 +18,13 @@
 #ifndef MROM_DATA_H
 #define MROM_DATA_H
 
+#define SECOND_BOOT_KMESG "MultiromSaysNextBootShouldBeSecondMagic108\n"
+
 void mrom_set_dir(const char *mrom_dir);
 void mrom_set_log_tag(const char *tag);
 
 const char *mrom_log_tag(void);
 const char *mrom_dir(void);
+int mrom_is_second_boot(void);
 
 #endif

multirom.c

@@ -60,7 +60,6 @@
 #define INTERNAL_ROM_NAME "Internal"
 #define MAX_ROM_NAME_LEN 26
 #define LAYOUT_VERSION "/data/.layout_version"
-#define SECOND_BOOT_KMESG "MultiromSaysNextBootShouldBeSecondMagic108\n"
 
 #define BATTERY_CAP "/sys/class/power_supply/battery/capacity"
 
@@ -473,6 +472,9 @@ int multirom_load_status(struct multirom_status *s)
 
     multirom_default_status(s);
 
+    if(mrom_is_second_boot())
+        s->is_second_boot = 1;
+
     char arg[256];
     sprintf(arg, "%s/multirom.ini", mrom_dir());
 
@@ -490,19 +492,6 @@ int multirom_load_status(struct multirom_status *s)
     char name[64];
     char *pch;
 
-    if(multirom_search_last_kmsg(SECOND_BOOT_KMESG) == 0)
-        s->is_second_boot = 1;
-    else
-    {
-        FILE *cmdline = fopen("/proc/cmdline", "re");
-        if(cmdline)
-        {
-            if(fgets(line, sizeof(line), cmdline) && strstr(line, "mrom_kexecd=1"))
-                s->is_second_boot = 1;
-            fclose(cmdline);
-        }
-    }
-
     while((fgets(line, sizeof(line), f)))
     {
         pch = strtok (line, "=\n");
@@ -2438,38 +2427,6 @@ struct usb_partition *multirom_get_partition(struct multirom_status *s, char *uu
     return NULL;
 }
 
-int multirom_search_last_kmsg(const char *expr)
-{
-    int i;
-    int res = -1;
-    FILE *f = NULL;
-    char buff[2048];
-
-    static const char *kmsg_paths[] = {
-        "/proc/last_kmsg",
-        "/sys/fs/pstore/console-ramoops",
-        NULL,
-    };
-
-    for(i = 0; !f && kmsg_paths[i]; ++i)
-        f = fopen(kmsg_paths[i], "re");
-
-    if(!f)
-        return -1;
-
-    while(fgets(buff, sizeof(buff), f))
-    {
-        if(strstr(buff, expr))
-        {
-            res = 0;
-            break;
-        }
-    }
-
-    fclose(f);
-    return res;
-}
-
 int multirom_get_battery(void)
 {
     char buff[4];

multirom.h

@@ -155,7 +155,6 @@ int multirom_copy_log(char *klog, const char *dest_path_relative);
 int multirom_scan_partition_for_roms(struct multirom_status *s, struct usb_partition *p);
 struct usb_partition *multirom_get_partition(struct multirom_status *s, char *uuid);
 int multirom_path_exists(char *base, char *filename);
-int multirom_search_last_kmsg(const char *expr);
 struct rom_info *multirom_parse_rom_info(struct multirom_status *s, struct multirom_rom *rom);
 void multirom_destroy_rom_info(struct rom_info *info);
 char **multirom_get_rom_info_str(struct rom_info *info, char *key);

trampoline/trampoline.c

@@ -24,6 +24,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <dirent.h>
+#include <cutils/android_reboot.h>
 
 #include "devices.h"
 #include "../lib/log.h"
@@ -146,19 +147,23 @@ static int try_mount_all_entries(struct fstab *fstab, struct fstab_part *first_d
     return -1;
 }
 
-static void mount_and_run(struct fstab *fstab)
+static int mount_and_run(struct fstab *fstab)
 {
     struct fstab_part *datap = fstab_find_first_by_path(fstab, "/data");
     if(!datap)
     {
         ERROR("Failed to find /data partition in fstab\n");
-        return;
+        return -1;
     }
 
-    if(wait_for_file(datap->device, 5) < 0)
+    if(access(datap->device, R_OK) < 0)
     {
-        ERROR("Waiting too long for dev %s\n", datap->device);
-        return;
+        INFO("Waiting for %s\n", datap->device);
+        if(wait_for_file(datap->device, 5) < 0)
+        {
+            ERROR("Waiting too long for dev %s\n", datap->device);
+            return -1;
+        }
     }
 
     mkdir(REALDATA, 0755);
@@ -167,23 +172,23 @@ static void mount_and_run(struct fstab *fstab)
     {
 #ifndef MR_ENCRYPTION
         ERROR("Failed to mount /data with all possible filesystems!\n");
-        return;
+        return -1;
 #else
         INFO("Failed to mount /data, trying encryption...\n");
         switch(encryption_before_mount(fstab))
         {
             case ENC_RES_ERR:
                 ERROR("/data decryption failed!\n");
-                return;
+                return -1;
             case ENC_RES_BOOT_INTERNAL:
-                return;
+                return 0;
             default:
             case ENC_RES_OK:
             {
                 if(try_mount_all_entries(fstab, datap) < 0)
                 {
                     ERROR("Failed to mount decrypted /data with all possible filesystems!\n");
-                    return;
+                    return -1;
                 }
                 break;
             }
@@ -194,12 +199,13 @@ static void mount_and_run(struct fstab *fstab)
     if(find_multirom() == -1)
     {
         ERROR("Could not find multirom folder!\n");
-        return;
+        return -1;
     }
 
     adb_init(path_multirom);
     run_multirom();
     adb_quit();
+    return 0;
 }
 
 static int is_charger_mode(void)
@@ -339,7 +345,14 @@ int main(int argc, char *argv[])
 #endif
 
     // mount and run multirom from sdcard
-    mount_and_run(fstab);
+    if(mount_and_run(fstab) < 0 && mrom_is_second_boot())
+    {
+        ERROR("This is second boot and we couldn't mount /data, reboot!\n");
+        sync();
+        android_reboot(ANDROID_RB_RESTART, 0, 0);
+        while(1)
+            sleep(1);
+    }
 
 exit:
     if(fstab)