osutil: fix bugs on locking sdcard in Windows

* Remove 'pid' on filename of sdcard lock. It makes that only a single emulator
  can attach the same sdcard image.
* Check whether sdcard is already attached or not when try to attach sdcard
* Check whether sdcard is attached and same when try to detach sdcard
* Refactoring
** Just CloseHandle() when detach sdcard. It is sufficient to remove the
   lock file
** Remove redundant memory allocation

Change-Id: Ib6611dceffa5b9e6dfaf10fb450b9c7b218687b7
Signed-off-by: Sangho Park <sangho.p@samsung.com>

1 files changed, 57 insertions, 49 deletions

diff --git a/tizen/src/util/osutil-win32.c b/tizen/src/util/osutil-win32.c
index f1e3f80d7c..388d7dfa05 100644
--- a/tizen/src/util/osutil-win32.c
+++ b/tizen/src/util/osutil-win32.c
@@ -51,8 +51,10 @@ DECLARE_DEBUG_CHANNEL(osutil);
 static char *lock_filename;
 static HANDLE lock_file = INVALID_HANDLE_VALUE;
 
-static char g_sdcard[256] = {0,};
-static sdcard_info info;
+static sdcard_info info = {
+    .handle = INVALID_HANDLE_VALUE,
+    .lock_file = NULL,
+};
 
 static void remove_vm_lock_os(void)
 {
@@ -181,61 +183,67 @@ void print_system_info_os(void)
 
 bool make_sdcard_lock_os(char *sdcard)
 {
-    char *lock_file = g_strdup_printf("%s-%d.lck", sdcard, getpid());
-
-    HANDLE hFile = CreateFile(lock_file, GENERIC_READ,
-            FILE_SHARE_READ | FILE_SHARE_DELETE,
-            0,
-            CREATE_ALWAYS,
-            FILE_ATTRIBUTE_NORMAL | FILE_FLAG_DELETE_ON_CLOSE,
-            NULL);
-
-    if (hFile == INVALID_HANDLE_VALUE) {
-        if (GetLastError() == ERROR_SHARING_VIOLATION) {
-            if (strcmp(g_sdcard, sdcard) == 0) {
-                LOG_INFO("try to mount same sdcard!\n");
-            }
-            return false;
-        }
-        return true;
+    HANDLE  h;
+    char    *fname;
+
+    if (info.handle != INVALID_HANDLE_VALUE) {
+        g_assert(info.lock_file != NULL);
+        LOG_INFO("sdcard(%s) is already attached\n", info.lock_file);
+        return false;
+    }
+
+    fname = g_strdup_printf("%s.lck", sdcard);
+    h = CreateFile(fname,
+                   GENERIC_READ,
+                   0,               // No share
+                   NULL,
+                   CREATE_ALWAYS,
+                   FILE_ATTRIBUTE_NORMAL | FILE_FLAG_DELETE_ON_CLOSE,
+                   NULL);
+
+    if (h == INVALID_HANDLE_VALUE) {
+        LOG_WARNING("Failed to CreateFile a sdcard lock file: %d\n",
+                 (DWORD)GetLastError());
+        g_free(fname);
+        return false;
+    }
+
+    /* If the lock file exists and CreateFile() succeeded, just go on.
+     * If other emulator locks the sdcard, CreateFile failed owing to
+     * ERROR_SHARING_VIOLATION. Therefore, no emulator opened the lock file
+     * and just go on attaching sdcard.
+     */
+    if (GetLastError() != ERROR_ALREADY_EXISTS) {
+        LOG_WARNING("The lock file exists but CreateFile succeeded. Just go on\n");
     }
-    LOG_INFO("Get file lock: %s\n", lock_file);
-    strncpy(g_sdcard, sdcard, strlen(sdcard));
-    info.handle = hFile;
+
+    info.handle = h;
+    info.lock_file = fname;
+    LOG_INFO("Locked sdcard: %s\n", fname);
     return true;
 
 }
 
 int remove_sdcard_lock_os(char *sdcard)
 {
-    char *lock_file = g_strdup_printf("%s-%d.lck", sdcard, getpid());
-    HANDLE hFile2;
-    hFile2 = CreateFile(lock_file, GENERIC_READ,
-            0,
-            NULL,
-            OPEN_EXISTING,
-            FILE_ATTRIBUTE_NORMAL,
-            NULL);
-    /* to check if previous lock exists */
-    if (hFile2 == INVALID_HANDLE_VALUE) {
-        if (GetLastError() == ERROR_SHARING_VIOLATION) {
-            if (strncmp(g_sdcard, sdcard, strlen(sdcard)) != 0) {
-                LOG_INFO("not same sdcard!!!\n");
-                return ERR_UNLCK;
-            }
-
-            LOG_INFO("unlock success: %s\n", lock_file);
-            g_sdcard[0] = '\0';
-            CloseHandle(info.handle);
-            return ERR_SUCCESS;
-        } else {
-            return ERR_UNLCK;
-        }
-    } else {
-        LOG_TRACE("lockfile exists but, it is not locked.\n");
-        CloseHandle(hFile2);
-        return ERR_UNLCK;
+    /* check whether the sdcard is attached or not */
+    if (info.handle == INVALID_HANDLE_VALUE) {
+        LOG_INFO("No attached sdcard\n");
+        return ERR_NODEV;
     }
+
+    if (memcmp(sdcard, info.lock_file, strlen(sdcard)) != 0) {
+        LOG_INFO("%s is already attached\n", info.lock_file);
+        return ERR_NOENT;
+    }
+
+    /* CloseHandle(info.handle) will remove the lock file */
+    LOG_INFO("Unlocked sdcard\n");
+    CloseHandle(info.handle);
+    info.handle = INVALID_HANDLE_VALUE;
+    g_free(info.lock_file);
+    info.lock_file = NULL;
+    return ERR_SUCCESS;
 }
 
 /* Gets the JavaHome path from the windows registry.