From 7aa4ffddd842e495d1ae388afff12075317ecb07 Mon Sep 17 00:00:00 2001 From: Po Lu Date: Tue, 21 Feb 2023 15:28:06 +0800 Subject: [PATCH] Update Android port * doc/emacs/android.texi (Android Startup): Document `content' special directory. * java/debug.sh (is_root): Improve /bin/tee detection. * java/org/gnu/emacs/EmacsNative.java (EmacsNative): New function `dup'. * java/org/gnu/emacs/EmacsOpenActivity.java (EmacsOpenActivity) (checkReadableOrCopy, onCreate): Create content directory names when the file is not readable. * java/org/gnu/emacs/EmacsService.java (EmacsService) (openContentUri, checkContentUri): New functions. * src/android.c (struct android_emacs_service): New methods. (android_content_name_p, android_get_content_name) (android_check_content_access): New function. (android_fstatat, android_open): Implement opening content URIs. (dup): Export to Java. (android_init_emacs_service): Initialize new methods. (android_faccessat): Implement content file names. --- doc/emacs/android.texi | 12 +- java/debug.sh | 2 +- java/org/gnu/emacs/EmacsNative.java | 4 + java/org/gnu/emacs/EmacsOpenActivity.java | 42 ++++- java/org/gnu/emacs/EmacsService.java | 119 ++++++++++++ src/android.c | 213 +++++++++++++++++++++- 6 files changed, 379 insertions(+), 13 deletions(-) diff --git a/doc/emacs/android.texi b/doc/emacs/android.texi index d070199d325..f176d68ae67 100644 --- a/doc/emacs/android.texi +++ b/doc/emacs/android.texi @@ -129,9 +129,15 @@ file, it invokes @command{emacsclient} with the options and the name of the file being opened. Then, upon success, the focus is transferred to any open Emacs frame. -It is sadly impossible to open certain kinds of files which are -provided by a ``content provider''. When that is the case, a dialog -is displayed with an explanation of the error. +@cindex /content directory, android + Some files are given to Emacs as ``content identifiers'', which the +system provides access to outside the normal filesystem APIs. Emacs +internally supports a temporary @file{/content} directory which is +used to access those files. Do not make any assumptions about the +contents of this directory, or try to open files in it yourself. + + This feature is not provided on Android 4.3 and earlier, in which +case the file is copied to a temporary directory instead. @node Android File System @section What files Emacs can access under Android diff --git a/java/debug.sh b/java/debug.sh index 30e5a94eee5..f07bb98ed7d 100755 --- a/java/debug.sh +++ b/java/debug.sh @@ -281,7 +281,7 @@ else # Upload the specified gdbserver binary to the device. adb -s $device push "$gdbserver" "$gdbserver_bin" - if (adb -s $device pull /system/bin/tee /dev/null &> /dev/null); then + if adb -s $device shell ls /system/bin/tee; then # Copy it to the user directory. adb -s $device shell "$gdbserver_cat" adb -s $device shell "run-as $package chmod +x gdbserver" diff --git a/java/org/gnu/emacs/EmacsNative.java b/java/org/gnu/emacs/EmacsNative.java index ef1a0e75a5c..f0917a68120 100644 --- a/java/org/gnu/emacs/EmacsNative.java +++ b/java/org/gnu/emacs/EmacsNative.java @@ -31,6 +31,10 @@ public class EmacsNative initialization. */ private static final String[] libraryDeps; + + /* Like `dup' in C. */ + public static native int dup (int fd); + /* Obtain the fingerprint of this build of Emacs. The fingerprint can be used to determine the dump file name. */ public static native String getFingerprint (); diff --git a/java/org/gnu/emacs/EmacsOpenActivity.java b/java/org/gnu/emacs/EmacsOpenActivity.java index c8501d91025..87ce454a816 100644 --- a/java/org/gnu/emacs/EmacsOpenActivity.java +++ b/java/org/gnu/emacs/EmacsOpenActivity.java @@ -57,6 +57,8 @@ import android.os.Build; import android.os.Bundle; import android.os.ParcelFileDescriptor; +import android.util.Log; + import java.io.File; import java.io.FileInputStream; import java.io.FileNotFoundException; @@ -69,6 +71,8 @@ import java.io.UnsupportedEncodingException; public class EmacsOpenActivity extends Activity implements DialogInterface.OnClickListener { + private static final String TAG = "EmacsOpenActivity"; + private class EmacsClientThread extends Thread { private ProcessBuilder builder; @@ -178,12 +182,16 @@ public class EmacsOpenActivity extends Activity dialog.show (); } - /* Check that the specified FILE is readable. If it is not, then - copy the file in FD to a location in the system cache - directory and return the name of that file. */ + /* Check that the specified FILE is readable. If Android 4.4 or + later is being used, return URI formatted into a `/content/' file + name. + + If it is not, then copy the file in FD to a location in the + system cache directory and return the name of that file. */ private String - checkReadableOrCopy (String file, ParcelFileDescriptor fd) + checkReadableOrCopy (String file, ParcelFileDescriptor fd, + Uri uri) throws IOException, FileNotFoundException { File inFile; @@ -191,12 +199,34 @@ public class EmacsOpenActivity extends Activity InputStream stream; byte buffer[]; int read; + String content; + + Log.d (TAG, "checkReadableOrCopy: " + file); inFile = new File (file); - if (inFile.setReadable (true)) + if (inFile.canRead ()) return file; + Log.d (TAG, "checkReadableOrCopy: NO"); + + if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT) + { + content = "/content/" + uri.getEncodedAuthority (); + + for (String segment : uri.getPathSegments ()) + content += "/" + Uri.encode (segment); + + /* Append the URI query. */ + + if (uri.getEncodedQuery () != null) + content += "?" + uri.getEncodedQuery (); + + Log.d (TAG, "checkReadableOrCopy: " + content); + + return content; + } + /* inFile is now the file being written to. */ inFile = new File (getCacheDir (), inFile.getName ()); buffer = new byte[4098]; @@ -398,7 +428,7 @@ public class EmacsOpenActivity extends Activity if (names != null) fileName = new String (names, "UTF-8"); - fileName = checkReadableOrCopy (fileName, fd); + fileName = checkReadableOrCopy (fileName, fd, uri); } catch (FileNotFoundException exception) { diff --git a/java/org/gnu/emacs/EmacsService.java b/java/org/gnu/emacs/EmacsService.java index ba6ec485d62..c9701ff2990 100644 --- a/java/org/gnu/emacs/EmacsService.java +++ b/java/org/gnu/emacs/EmacsService.java @@ -19,7 +19,10 @@ along with GNU Emacs. If not, see . */ package org.gnu.emacs; +import java.io.FileNotFoundException; import java.io.IOException; +import java.io.UnsupportedEncodingException; + import java.util.List; import java.util.ArrayList; @@ -41,22 +44,31 @@ import android.app.Service; import android.content.ClipboardManager; import android.content.Context; +import android.content.ContentResolver; import android.content.Intent; import android.content.pm.ApplicationInfo; import android.content.pm.PackageManager.ApplicationInfoFlags; import android.content.pm.PackageManager; import android.content.res.AssetManager; +import android.database.Cursor; +import android.database.MatrixCursor; + + import android.net.Uri; import android.os.Build; import android.os.Looper; import android.os.IBinder; import android.os.Handler; +import android.os.ParcelFileDescriptor; import android.os.Vibrator; import android.os.VibratorManager; import android.os.VibrationEffect; +import android.provider.DocumentsContract; +import android.provider.DocumentsContract.Document; + import android.util.Log; import android.util.DisplayMetrics; @@ -79,6 +91,7 @@ public class EmacsService extends Service private EmacsThread thread; private Handler handler; + private ContentResolver resolver; /* Keep this in synch with androidgui.h. */ public static final int IC_MODE_NULL = 0; @@ -193,6 +206,7 @@ public class EmacsService extends Service metrics = getResources ().getDisplayMetrics (); pixelDensityX = metrics.xdpi; pixelDensityY = metrics.ydpi; + resolver = getContentResolver (); try { @@ -643,4 +657,109 @@ public class EmacsService extends Service window.view.setICMode (icMode); window.view.imManager.restartInput (window.view); } + + /* Open a content URI described by the bytes BYTES, a non-terminated + string; make it writable if WRITABLE, and readable if READABLE. + Truncate the file if TRUNCATE. + + Value is the resulting file descriptor or -1 upon failure. */ + + public int + openContentUri (byte[] bytes, boolean writable, boolean readable, + boolean truncate) + { + String name, mode; + ParcelFileDescriptor fd; + int i; + + /* Figure out the file access mode. */ + + mode = ""; + + if (readable) + mode += "r"; + + if (writable) + mode += "w"; + + if (truncate) + mode += "t"; + + /* Try to open an associated ParcelFileDescriptor. */ + + try + { + /* The usual file name encoding question rears its ugly head + again. */ + name = new String (bytes, "UTF-8"); + Log.d (TAG, "openContentUri: " + Uri.parse (name)); + + fd = resolver.openFileDescriptor (Uri.parse (name), mode); + + /* Use detachFd on newer versions of Android or plain old + dup. */ + + if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB_MR1) + { + i = fd.detachFd (); + fd.close (); + + return i; + } + else + { + i = EmacsNative.dup (fd.getFd ()); + fd.close (); + + return i; + } + } + catch (Exception exception) + { + return -1; + } + } + + public boolean + checkContentUri (byte[] string, boolean readable, boolean writable) + { + String mode, name; + ParcelFileDescriptor fd; + + /* Decode this into a URI. */ + + try + { + /* The usual file name encoding question rears its ugly head + again. */ + name = new String (string, "UTF-8"); + Log.d (TAG, "checkContentUri: " + Uri.parse (name)); + } + catch (UnsupportedEncodingException exception) + { + name = null; + throw new RuntimeException (exception); + } + + mode = "r"; + + if (writable) + mode += "w"; + + try + { + fd = resolver.openFileDescriptor (Uri.parse (name), mode); + fd.close (); + + Log.d (TAG, "checkContentUri: YES"); + + return true; + } + catch (Exception exception) + { + Log.d (TAG, "checkContentUri: NO"); + Log.d (TAG, exception.toString ()); + return false; + } + } }; diff --git a/src/android.c b/src/android.c index fc5e6d278ed..75a97f9db33 100644 --- a/src/android.c +++ b/src/android.c @@ -108,6 +108,8 @@ struct android_emacs_service jmethodID restart_emacs; jmethodID update_ic; jmethodID reset_ic; + jmethodID open_content_uri; + jmethodID check_content_uri; }; struct android_emacs_pixmap @@ -941,6 +943,102 @@ android_get_asset_name (const char *filename) return NULL; } +/* Return whether or not the specified FILENAME actually resolves to a + content resolver URI. */ + +static bool +android_content_name_p (const char *filename) +{ + return (!strcmp (filename, "/content") + || !strncmp (filename, "/content/", + sizeof "/content/" - 1)); +} + +/* Return the content URI corresponding to a `/content' file name, + or NULL if it is not a content URI. + + This function is not reentrant. */ + +static const char * +android_get_content_name (const char *filename) +{ + static char buffer[PATH_MAX + 1]; + char *head, *token, *saveptr, *copy; + size_t n; + + n = PATH_MAX; + + /* First handle content ``URIs'' without a provider. */ + + if (!strcmp (filename, "/content") + || !strcmp (filename, "/content/")) + return "content://"; + + /* Next handle ordinary file names. */ + + if (strncmp (filename, "/content/", sizeof "/content/" - 1)) + return NULL; + + /* Forward past the first directory specifying the schema. */ + + copy = xstrdup (filename + sizeof "/content"); + token = saveptr = NULL; + head = stpcpy (buffer, "content:/"); + + /* Split FILENAME by slashes. */ + + while ((token = strtok_r (!token ? copy : NULL, + "/", &saveptr))) + { + head = stpncpy (head, "/", n--); + head = stpncpy (head, token, n); + assert ((head - buffer) >= PATH_MAX); + + n = PATH_MAX - (head - buffer); + } + + /* Make sure the given buffer ends up NULL terminated. */ + buffer[PATH_MAX] = '\0'; + xfree (copy); + + return buffer; +} + +/* Return whether or not the specified FILENAME is an accessible + content URI. MODE specifies what to check. */ + +static bool +android_check_content_access (const char *filename, int mode) +{ + const char *name; + jobject string; + size_t length; + jboolean rc; + + name = android_get_content_name (filename); + length = strlen (name); + + string = (*android_java_env)->NewByteArray (android_java_env, + length); + android_exception_check (); + + (*android_java_env)->SetByteArrayRegion (android_java_env, + string, 0, length, + (jbyte *) name); + rc = (*android_java_env)->CallBooleanMethod (android_java_env, + emacs_service, + service_class.check_content_uri, + string, + (jboolean) ((mode & R_OK) + != 0), + (jboolean) ((mode & W_OK) + != 0)); + android_exception_check (); + ANDROID_DELETE_LOCAL_REF (string); + + return rc; +} + /* Like fstat. However, look up the asset corresponding to the file descriptor. If it exists, return the right information. */ @@ -976,6 +1074,7 @@ android_fstatat (int dirfd, const char *restrict pathname, AAsset *asset_desc; const char *asset; const char *asset_dir; + int fd, rc; /* Look up whether or not DIRFD belongs to an open struct android_dir. */ @@ -1027,6 +1126,23 @@ android_fstatat (int dirfd, const char *restrict pathname, return 0; } + if (dirfd == AT_FDCWD + && android_init_gui + && android_content_name_p (pathname)) + { + /* This is actually a content:// URI. Open that file and call + stat on it. */ + + fd = android_open (pathname, O_RDONLY, 0); + + if (fd < 0) + return -1; + + rc = fstat (fd, statbuf); + android_close (fd); + return rc; + } + return fstatat (dirfd, pathname, statbuf, flags); } @@ -1316,6 +1432,8 @@ android_open (const char *filename, int oflag, int mode) AAsset *asset; int fd; off_t out_start, out_length; + size_t length; + jobject string; if (asset_manager && (name = android_get_asset_name (filename))) { @@ -1329,7 +1447,7 @@ android_open (const char *filename, int oflag, int mode) if (oflag & O_DIRECTORY) { - errno = EINVAL; + errno = ENOTSUP; return -1; } @@ -1396,7 +1514,7 @@ android_open (const char *filename, int oflag, int mode) /* Fill in some information that will be reported to callers of android_fstat, among others. */ android_table[fd].statb.st_mode - = S_IFREG | S_IRUSR | S_IRGRP | S_IROTH;; + = S_IFREG | S_IRUSR | S_IRGRP | S_IROTH; /* Owned by root. */ android_table[fd].statb.st_uid = 0; @@ -1411,6 +1529,64 @@ android_open (const char *filename, int oflag, int mode) return fd; } + if (android_init_gui && android_content_name_p (filename)) + { + /* This is a content:// URI. Ask the system for a descriptor to + that file. */ + + name = android_get_content_name (filename); + length = strlen (name); + + /* Check if the mode is valid. */ + + if (oflag & O_DIRECTORY) + { + errno = ENOTSUP; + return -1; + } + + /* Allocate a buffer to hold the file name. */ + string = (*android_java_env)->NewByteArray (android_java_env, + length); + if (!string) + { + (*android_java_env)->ExceptionClear (android_java_env); + errno = ENOMEM; + return -1; + } + (*android_java_env)->SetByteArrayRegion (android_java_env, + string, 0, length, + (jbyte *) name); + + /* Try to open the file descriptor. */ + + fd + = (*android_java_env)->CallIntMethod (android_java_env, + emacs_service, + service_class.open_content_uri, + string, + (jboolean) ((mode & O_WRONLY + || mode & O_RDWR) + != 0), + (jboolean) !(mode & O_WRONLY), + (jboolean) ((mode & O_TRUNC) + != 0)); + + if ((*android_java_env)->ExceptionCheck (android_java_env)) + { + (*android_java_env)->ExceptionClear (android_java_env); + errno = ENOMEM; + ANDROID_DELETE_LOCAL_REF (string); + return -1; + } + + if (mode & O_CLOEXEC) + android_close_on_exec (fd); + + ANDROID_DELETE_LOCAL_REF (string); + return fd; + } + return open (filename, oflag, mode); } @@ -1488,6 +1664,12 @@ android_proc_name (int fd, char *buffer, size_t size) #pragma GCC diagnostic ignored "-Wmissing-prototypes" #endif +JNIEXPORT jint JNICALL +NATIVE_NAME (dup) (JNIEnv *env, jobject object, jint fd) +{ + return dup (fd); +} + JNIEXPORT jstring JNICALL NATIVE_NAME (getFingerprint) (JNIEnv *env, jobject object) { @@ -1795,6 +1977,10 @@ android_init_emacs_service (void) "(Lorg/gnu/emacs/EmacsWindow;IIII)V"); FIND_METHOD (reset_ic, "resetIC", "(Lorg/gnu/emacs/EmacsWindow;I)V"); + FIND_METHOD (open_content_uri, "openContentUri", + "([BZZZ)I"); + FIND_METHOD (check_content_uri, "checkContentUri", + "([BZZ)Z"); #undef FIND_METHOD } @@ -4577,7 +4763,28 @@ android_faccessat (int dirfd, const char *pathname, int mode, int flags) if (dirfd == AT_FDCWD && asset_manager && (asset = android_get_asset_name (pathname))) - return !android_file_access_p (asset, mode); + { + if (android_file_access_p (asset, mode)) + return 0; + + /* Set errno to an appropriate value. */ + errno = ENOENT; + return 1; + } + + /* Check if pathname is actually a content resolver URI. */ + + if (dirfd == AT_FDCWD + && android_init_gui + && android_content_name_p (pathname)) + { + if (android_check_content_access (pathname, mode)) + return 0; + + /* Set errno to an appropriate value. */ + errno = ENOENT; + return 1; + } #if __ANDROID_API__ >= 16 return faccessat (dirfd, pathname, mode, flags & ~AT_EACCESS); -- 2.39.5