diff --git a/tools/atree/Android.mk b/tools/atree/Android.mk
new file mode 100644
index 0000000..d895810
--- /dev/null
+++ b/tools/atree/Android.mk
@@ -0,0 +1,20 @@
+# Copyright 2007 The Android Open Source Project
+#
+# Copies files into the directory structure described by a manifest
+
+LOCAL_PATH:= $(call my-dir)
+include $(CLEAR_VARS)
+
+LOCAL_SRC_FILES := \
+	atree.cpp \
+	files.cpp \
+	fs.cpp
+
+LOCAL_STATIC_LIBRARIES := \
+	libhost
+LOCAL_C_INCLUDES := build/libs/host/include
+
+LOCAL_MODULE := atree
+
+include $(BUILD_HOST_EXECUTABLE)
+
diff --git a/tools/atree/atree.cpp b/tools/atree/atree.cpp
new file mode 100644
index 0000000..4d97d24
--- /dev/null
+++ b/tools/atree/atree.cpp
@@ -0,0 +1,274 @@
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+#include "options.h"
+#include "files.h"
+#include "fs.h"
+#include <set>
+
+using namespace std;
+
+bool g_debug = false;
+vector<string> g_listFiles;
+vector<string> g_inputBases;
+string g_outputBase;
+string g_dependency;
+bool g_useHardLinks = false;
+
+const char* USAGE =
+"\n"
+"Usage: atree OPTIONS\n"
+"\n"
+"Options:\n"
+"  -f FILELIST    Specify one or more files containing the\n"
+"                 list of files to copy.\n"
+"  -I INPUTDIR    Specify one or more base directories in\n"
+"                 which to look for the files\n"
+"  -o OUTPUTDIR   Specify the directory to copy all of the\n"
+"                 output files to.\n"
+"  -l             Use hard links instead of copying the files.\n"
+"  -m DEPENDENCY  Output a make-formatted file containing the list.\n"
+"                 of files included.  It sets the variable ATREE_FILES.\n"
+"\n"
+"FILELIST file format:\n"
+"  The FILELIST files contain the list of files that will end up\n"
+"  in the final OUTPUTDIR.  Atree will look for files in the INPUTDIR\n"
+"  directories in the order they are specified.\n"
+"\n"
+"  In a FILELIST file, comment lines start with a #.  Other lines\n"
+"  are of the format:\n"
+"\n"
+"    DEST\n"
+"    SRC DEST\n"
+"    -SRCPATTERN\n"
+"\n"
+"  DEST should be path relative to the output directory.\n"
+"  If SRC is supplied, the file names can be different.\n"
+"  SRCPATTERN is a pattern for the filenames.\n"
+"\n";
+
+int usage()
+{
+    fwrite(USAGE, strlen(USAGE), 1, stderr);
+    return 1;
+}
+
+int
+main(int argc, char* const* argv)
+{
+    int err;
+    bool done = false;
+    while (!done) {
+        int opt = getopt(argc, argv, "f:I:o:hlm:");
+        switch (opt)
+        {
+            case -1:
+                done = true;
+                break;
+            case 'f':
+                g_listFiles.push_back(string(optarg));
+                break;
+            case 'I':
+                g_inputBases.push_back(string(optarg));
+                break;
+            case 'o':
+                if (g_outputBase.length() != 0) {
+                    fprintf(stderr, "%s: -o may only be supplied once -- "
+                                "-o %s\n", argv[0], optarg);
+                    return usage();
+                }
+                g_outputBase = optarg;
+                break;
+            case 'l':
+                g_useHardLinks = true;
+                break;
+            case 'm':
+                if (g_dependency.length() != 0) {
+                    fprintf(stderr, "%s: -m may only be supplied once -- "
+                                "-m %s\n", argv[0], optarg);
+                    return usage();
+                }
+                g_dependency = optarg;
+                break;
+            default:
+            case '?':
+            case 'h':
+                return usage();
+        }
+    }
+    if (optind != argc) {
+        fprintf(stderr, "%s: invalid argument -- %s\n", argv[0], argv[optind]);
+        return usage();
+    }
+
+    if (g_listFiles.size() == 0) {
+        fprintf(stderr, "%s: At least one -f option must be supplied.\n",
+                 argv[0]);
+        return usage();
+    }
+
+    if (g_inputBases.size() == 0) {
+        fprintf(stderr, "%s: At least one -I option must be supplied.\n",
+                 argv[0]);
+        return usage();
+    }
+
+    if (g_outputBase.length() == 0) {
+        fprintf(stderr, "%s: -o option must be supplied.\n", argv[0]);
+        return usage();
+    }
+
+
+#if 0
+    for (vector<string>::iterator it=g_listFiles.begin();
+                                it!=g_listFiles.end(); it++) {
+        printf("-f \"%s\"\n", it->c_str());
+    }
+    for (vector<string>::iterator it=g_inputBases.begin();
+                                it!=g_inputBases.end(); it++) {
+        printf("-I \"%s\"\n", it->c_str());
+    }
+    printf("-o \"%s\"\n", g_outputBase.c_str());
+    if (g_useHardLinks) {
+        printf("-l\n");
+    }
+#endif
+
+    vector<FileRecord> files;
+    vector<FileRecord> more;
+    vector<string> excludes;
+    set<string> directories;
+    set<string> deleted;
+
+    // read file lists
+    for (vector<string>::iterator it=g_listFiles.begin();
+                                it!=g_listFiles.end(); it++) {
+        err = read_list_file(*it, &files, &excludes);
+        if (err != 0) {
+            return err;
+        }
+    }
+
+    // look for input files
+    err = 0;
+    for (vector<FileRecord>::iterator it=files.begin();
+                                it!=files.end(); it++) {
+        err |= locate(&(*it), g_inputBases);
+
+    }
+    
+    // expand the directories that we should copy into a list of files
+    for (vector<FileRecord>::iterator it=files.begin();
+                                it!=files.end(); it++) {
+        if (it->sourceIsDir) {
+            err |= list_dir(*it, excludes, &more);
+        }
+    }
+    for (vector<FileRecord>::iterator it=more.begin();
+                                it!=more.end(); it++) {
+        files.push_back(*it);
+    }
+
+    // get the name and modtime of the output files
+    for (vector<FileRecord>::iterator it=files.begin();
+                                it!=files.end(); it++) {
+        stat_out(g_outputBase, &(*it));
+    }
+
+    if (err != 0) {
+        return 1;
+    }
+
+    // gather directories
+    for (vector<FileRecord>::iterator it=files.begin();
+                                it!=files.end(); it++) {
+        if (it->sourceIsDir) {
+            directories.insert(it->outPath);
+        } else {
+            string s = dir_part(it->outPath);
+            if (s != ".") {
+                directories.insert(s);
+            }
+        }
+    }
+
+    // gather files that should become directores and directories that should
+    // become files
+    for (vector<FileRecord>::iterator it=files.begin();
+                                it!=files.end(); it++) {
+        if (it->outMod != 0 && it->sourceIsDir != it->outIsDir) {
+            deleted.insert(it->outPath);
+        }
+    }
+
+    // delete files
+    for (set<string>::iterator it=deleted.begin();
+                                it!=deleted.end(); it++) {
+        if (g_debug) {
+            printf("deleting %s\n", it->c_str());
+        }
+        err = remove_recursively(*it);
+        if (err != 0) {
+            return err;
+        }
+    }
+
+    // make directories
+    for (set<string>::iterator it=directories.begin();
+                                it!=directories.end(); it++) {
+        if (g_debug) {
+            printf("mkdir %s\n", it->c_str());
+        }
+        err = mkdir_recursively(*it);
+        if (err != 0) {
+            return err;
+        }
+    }
+
+    // copy (or link) files
+    for (vector<FileRecord>::iterator it=files.begin();
+                                it!=files.end(); it++) {
+        if (!it->sourceIsDir) {
+            if (g_debug) {
+                printf("copy %s(%ld) ==> %s(%ld)", it->sourcePath.c_str(),
+                    it->sourceMod, it->outPath.c_str(), it->outMod);
+                fflush(stdout);
+            }
+
+            if (it->outMod < it->sourceMod) {
+                err = copy_file(it->sourcePath, it->outPath);
+                if (g_debug) {
+                    printf(" done.\n");
+                }
+                if (err != 0) {
+                    return err;
+                }
+            } else {
+                if (g_debug) {
+                    printf(" skipping.\n");
+                }
+            }
+        }
+    }
+
+    // output the dependency file
+    if (g_dependency.length() != 0) {
+        FILE *f = fopen(g_dependency.c_str(), "w");
+        if (f != NULL) {
+            fprintf(f, "ATREE_FILES := $(ATREE_FILES) \\\n");
+            for (vector<FileRecord>::iterator it=files.begin();
+                                it!=files.end(); it++) {
+                if (!it->sourceIsDir) {
+                    fprintf(f, "%s \\\n", it->sourcePath.c_str());
+                }
+            }
+            fprintf(f, "\n");
+            fclose(f);
+        } else {
+            fprintf(stderr, "error opening manifest file for write: %s\n",
+                    g_dependency.c_str());
+        }
+    }
+
+    return 0;
+}
diff --git a/tools/atree/files.cpp b/tools/atree/files.cpp
new file mode 100644
index 0000000..5842378
--- /dev/null
+++ b/tools/atree/files.cpp
@@ -0,0 +1,357 @@
+#include "files.h"
+#include <stdio.h>
+#include <errno.h>
+#include <sys/stat.h>
+#include <unistd.h>
+#include <dirent.h>
+#include <fnmatch.h>
+
+static bool
+is_comment_line(const char* p)
+{
+    while (*p && isspace(*p)) {
+        p++;
+    }
+    return *p == '#';
+}
+
+static string
+path_append(const string& base, const string& leaf)
+{
+    string full = base;
+    if (base.length() > 0 && leaf.length() > 0) {
+        full += '/';
+    }
+    full += leaf;
+    return full;
+}
+
+static bool
+is_whitespace_line(const char* p)
+{
+    while (*p) {
+        if (!isspace(*p)) {
+            return false;
+        }
+        p++;
+    }
+    return true;
+}
+
+static bool
+is_exclude_line(const char* p) {
+    while (*p) {
+        if (*p == '-') {
+            return true;
+        }
+        else if (isspace(*p)) {
+            p++;
+        }
+        else {
+            return false;
+        }
+    }
+    return false;
+}
+
+void
+split_line(const char* p, vector<string>* out)
+{
+    const char* q = p;
+    enum { WHITE, TEXT } state = WHITE;
+    while (*p) {
+        if (*p == '#') {
+            break;
+        }
+
+        switch (state)
+        {
+            case WHITE:
+                if (!isspace(*p)) {
+                    q = p;
+                    state = TEXT;
+                }
+                break;
+            case TEXT:
+                if (isspace(*p)) {
+                    if (q != p) {
+                        out->push_back(string(q, p-q));
+                    }
+                    state = WHITE;
+                }
+                break;
+        }
+        p++;
+    }
+    if (state == TEXT) {
+        out->push_back(string(q, p-q));
+    }
+}
+
+static void
+add_file(vector<FileRecord>* files, const string& listFile, int listLine,
+            const string& sourceName, const string& outName)
+{
+    FileRecord rec;
+    rec.listFile = listFile;
+    rec.listLine = listLine;
+    rec.sourceName = sourceName;
+    rec.outName = outName;
+    files->push_back(rec);
+}
+
+int
+read_list_file(const string& filename, vector<FileRecord>* files,
+                    vector<string>* excludes)
+{
+    int err = 0;
+    FILE* f = NULL;
+    long size;
+    char* buf = NULL;
+    char *p, *q;
+    int i, lineCount;
+
+    f = fopen(filename.c_str(), "r");
+    if (f == NULL) {
+        fprintf(stderr, "Could not open list file (%s): %s\n",
+                    filename.c_str(), strerror(errno));
+        err = errno;
+        goto cleanup;
+    }
+
+    err = fseek(f, 0, SEEK_END);
+    if (err != 0) {
+        fprintf(stderr, "Could not seek to the end of file %s. (%s)\n",
+                    filename.c_str(), strerror(errno));
+        err = errno;
+        goto cleanup;
+    }
+    
+    size = ftell(f);
+
+    err = fseek(f, 0, SEEK_SET);
+    if (err != 0) {
+        fprintf(stderr, "Could not seek to the beginning of file %s. (%s)\n",
+                    filename.c_str(), strerror(errno));
+        err = errno;
+        goto cleanup;
+    }
+
+    buf = (char*)malloc(size+1);
+    if (buf == NULL) {
+        // (potentially large)
+        fprintf(stderr, "out of memory (%ld)\n", size);
+        err = ENOMEM;
+        goto cleanup;
+    }
+
+    if (1 != fread(buf, size, 1, f)) {
+        fprintf(stderr, "error reading file %s. (%s)\n",
+                    filename.c_str(), strerror(errno));
+        err = errno;
+        goto cleanup;
+    }
+
+    // split on lines
+    p = buf;
+    q = buf+size;
+    lineCount = 0;
+    while (p<q) {
+        if (*p == '\r' || *p == '\n') {
+            *p = '\0';
+            lineCount++;
+        }
+        p++;
+    }
+
+    // read lines
+    p = buf;
+    for (i=0; i<lineCount; i++) {
+        int len = strlen(p);
+        q = p + len + 1;
+        if (is_whitespace_line(p) || is_comment_line(p)) {
+            ;
+        }
+        else if (is_exclude_line(p)) {
+            while (*p != '-') p++;
+            p++;
+            excludes->push_back(string(p));
+        }
+        else {
+            vector<string> words;
+
+            split_line(p, &words);
+
+#if 0
+            printf("[ ");
+            for (size_t k=0; k<words.size(); k++) {
+                printf("'%s' ", words[k].c_str());
+            }
+            printf("]\n");
+#endif
+            
+            if (words.size() == 1) {
+                // pattern: DEST
+                add_file(files, filename, i+1, words[0], words[0]);
+            }
+            else if (words.size() == 2) {
+                // pattern: SRC DEST
+                add_file(files, filename, i+1, words[0], words[1]);
+            }
+            else {
+                fprintf(stderr, "%s:%d: bad format: %s\n", filename.c_str(),
+                        i+1, p);
+                err = 1;
+            }
+        }
+        p = q;
+    }
+
+cleanup:
+    if (buf != NULL) {
+        free(buf);
+    }
+    if (f != NULL) {
+        fclose(f);
+    }
+    return err;
+}
+
+
+int
+locate(FileRecord* rec, const vector<string>& search)
+{
+    int err;
+
+    for (vector<string>::const_iterator it=search.begin();
+                it!=search.end(); it++) {
+        string full = path_append(*it, rec->sourceName);
+        struct stat st;
+        err = stat(full.c_str(), &st);
+        if (err == 0) {
+            rec->sourceBase = *it;
+            rec->sourcePath = full;
+            rec->sourceMod = st.st_mtime;
+            rec->sourceIsDir = S_ISDIR(st.st_mode);
+            return 0;
+        }
+    }
+
+    fprintf(stderr, "%s:%d: couldn't locate source file: %s\n",
+                rec->listFile.c_str(), rec->listLine, rec->sourceName.c_str());
+    return 1;
+}
+
+void
+stat_out(const string& base, FileRecord* rec)
+{
+    rec->outPath = path_append(base, rec->outName);
+
+    int err;
+    struct stat st;
+    err = stat(rec->outPath.c_str(), &st);
+    if (err == 0) {
+        rec->outMod = st.st_mtime;
+        rec->outIsDir = S_ISDIR(st.st_mode);
+    } else {
+        rec->outMod = 0;
+        rec->outIsDir = false;
+    }
+}
+
+string
+dir_part(const string& filename)
+{
+    int pos = filename.rfind('/');
+    if (pos <= 0) {
+        return ".";
+    }
+    return filename.substr(0, pos);
+}
+
+static void
+add_more(const string& entry, bool isDir,
+         const FileRecord& rec, vector<FileRecord>*more)
+{
+    FileRecord r;
+    r.listFile = rec.listFile;
+    r.listLine = rec.listLine;
+    r.sourceName = path_append(rec.sourceName, entry);
+    r.sourcePath = path_append(rec.sourceBase, r.sourceName);
+    struct stat st;
+    int err = stat(r.sourcePath.c_str(), &st);
+    if (err == 0) {
+        r.sourceMod = st.st_mtime;
+    }
+    r.sourceIsDir = isDir;
+    r.outName = path_append(rec.outName, entry);
+    more->push_back(r);
+}
+
+static bool
+matches_excludes(const char* file, const vector<string>& excludes)
+{
+    for (vector<string>::const_iterator it=excludes.begin();
+            it!=excludes.end(); it++) {
+        if (0 == fnmatch(it->c_str(), file, FNM_PERIOD)) {
+            return true;
+        }
+    }
+    return false;
+}
+
+static int
+list_dir(const string& path, const FileRecord& rec,
+                const vector<string>& excludes,
+                vector<FileRecord>* more)
+{
+    int err;
+
+    string full = path_append(rec.sourceBase, rec.sourceName);
+    full = path_append(full, path);
+
+    DIR *d = opendir(full.c_str());
+    if (d == NULL) {
+        return errno;
+    }
+
+    vector<string> dirs;
+
+    struct dirent *ent;
+    while (NULL != (ent = readdir(d))) {
+        if (0 == strcmp(".", ent->d_name)
+                || 0 == strcmp("..", ent->d_name)) {
+            continue;
+        }
+        if (matches_excludes(ent->d_name, excludes)) {
+            continue;
+        }
+        string entry = path_append(path, ent->d_name);
+#ifdef HAVE_DIRENT_D_TYPE
+		bool is_directory = (ent->d_type == DT_DIR);
+#else
+	    // If dirent.d_type is missing, then use stat instead
+		struct stat stat_buf;
+		stat(entry.c_str(), &stat_buf);
+		bool is_directory = S_ISDIR(stat_buf.st_mode);
+#endif
+        add_more(entry, is_directory, rec, more);
+        if (is_directory) {
+            dirs.push_back(entry);
+        }
+    }
+    closedir(d);
+
+    for (vector<string>::iterator it=dirs.begin(); it!=dirs.end(); it++) {
+        list_dir(*it, rec, excludes, more);
+    }
+
+    return 0;
+}
+
+int
+list_dir(const FileRecord& rec, const vector<string>& excludes,
+            vector<FileRecord>* files)
+{
+    return list_dir("", rec, excludes, files);
+}
diff --git a/tools/atree/files.h b/tools/atree/files.h
new file mode 100644
index 0000000..b8f0431
--- /dev/null
+++ b/tools/atree/files.h
@@ -0,0 +1,36 @@
+#ifndef FILES_H
+#define FILES_H
+
+#include <string>
+#include <vector>
+#include <sys/types.h>
+
+using namespace std;
+
+struct FileRecord
+{
+    string listFile;
+    int listLine;
+
+    string sourceBase;
+    string sourceName;
+    string sourcePath;
+    bool sourceIsDir;
+    time_t sourceMod;
+
+    string outName;
+    string outPath;
+    time_t outMod;
+    bool outIsDir;
+    unsigned int mode;
+};
+
+int read_list_file(const string& filename, vector<FileRecord>* files,
+                    vector<string>* excludes);
+int locate(FileRecord* rec, const vector<string>& search);
+void stat_out(const string& base, FileRecord* rec);
+string dir_part(const string& filename);
+int list_dir(const FileRecord& rec, const vector<string>& excludes,
+                    vector<FileRecord>* files);
+
+#endif // FILES_H
diff --git a/tools/atree/fs.cpp b/tools/atree/fs.cpp
new file mode 100644
index 0000000..15d6092
--- /dev/null
+++ b/tools/atree/fs.cpp
@@ -0,0 +1,142 @@
+#include "fs.h"
+#include "files.h"
+#include <unistd.h>
+#include <sys/types.h>
+#include <dirent.h>
+#include <string>
+#include <vector>
+#include <stdio.h>
+#include <errno.h>
+#include <sys/stat.h>
+#include <unistd.h>
+#include <host/CopyFile.h>
+
+using namespace std;
+
+static bool
+is_dir(const string& path)
+{
+    int err;
+    struct stat st;
+    err = stat(path.c_str(), &st);
+    return err != 0 || S_ISDIR(st.st_mode);
+}
+
+static int
+remove_file(const string& path)
+{
+    int err = unlink(path.c_str());
+    if (err != 0) {
+        fprintf(stderr, "error deleting file %s (%s)\n", path.c_str(),
+                strerror(errno));
+        return errno;
+    }
+    return 0;
+}
+
+int
+remove_recursively(const string& path)
+{
+    int err;
+
+    if (is_dir(path)) {
+        DIR *d = opendir(path.c_str());
+        if (d == NULL) {
+            fprintf(stderr, "error getting directory contents %s (%s)\n",
+                    path.c_str(), strerror(errno));
+            return errno;
+        }
+
+        vector<string> files;
+        vector<string> dirs;
+
+        struct dirent *ent;
+        while (NULL != (ent = readdir(d))) {
+            if (0 == strcmp(".", ent->d_name)
+                    || 0 == strcmp("..", ent->d_name)) {
+                continue;
+            }
+            string full = path;
+            full += '/';
+            full += ent->d_name;
+#ifdef HAVE_DIRENT_D_TYPE
+            bool is_directory = (ent->d_type == DT_DIR);
+#else
+	    	// If dirent.d_type is missing, then use stat instead
+			struct stat stat_buf;
+			stat(full.c_str(), &stat_buf);
+			bool is_directory = S_ISDIR(stat_buf.st_mode);
+#endif
+            if (is_directory) {
+                dirs.push_back(full);
+            } else {
+                files.push_back(full);
+            }
+        }
+        closedir(d);
+
+        for (vector<string>::iterator it=files.begin(); it!=files.end(); it++) {
+            err = remove_file(*it);
+            if (err != 0) {
+                return err;
+            }
+        }
+
+        for (vector<string>::iterator it=dirs.begin(); it!=dirs.end(); it++) {
+            err = remove_recursively(*it);
+            if (err != 0) {
+                return err;
+            }
+        }
+
+        err = rmdir(path.c_str());
+        if (err != 0) {
+            fprintf(stderr, "error deleting directory %s (%s)\n", path.c_str(),
+                    strerror(errno));
+            return errno;
+        }
+        return 0;
+    } else {
+        return remove_file(path);
+    }
+}
+
+int
+mkdir_recursively(const string& path)
+{
+    int err;
+    size_t pos = 0;
+    while (true) {
+        pos = path.find('/', pos);
+        string p = path.substr(0, pos);
+        struct stat st;
+        err = stat(p.c_str(), &st);
+        if (err != 0) {
+            err = mkdir(p.c_str(), 0770);
+            if (err != 0) {
+                fprintf(stderr, "can't create directory %s (%s)\n",
+                        path.c_str(), strerror(errno));
+                return errno;
+            }
+        }
+        else if (!S_ISDIR(st.st_mode)) {
+            fprintf(stderr, "can't create directory %s because %s is a file.\n",
+                        path.c_str(), p.c_str());
+            return 1;
+        }
+        pos++;
+        if (p == path) {
+            return 0;
+        }
+    }
+}
+
+int
+copy_file(const string& src, const string& dst)
+{
+    int err;
+
+    err = copyFile(src.c_str(), dst.c_str(),
+                    COPY_NO_DEREFERENCE | COPY_FORCE | COPY_PERMISSIONS);
+    return err;
+}
diff --git a/tools/atree/fs.h b/tools/atree/fs.h
new file mode 100644
index 0000000..4080880
--- /dev/null
+++ b/tools/atree/fs.h
@@ -0,0 +1,12 @@
+#ifndef FS_H
+#define FS_H
+
+#include <string>
+
+using namespace std;
+
+int remove_recursively(const string& path);
+int mkdir_recursively(const string& path);
+int copy_file(const string& src, const string& dst);
+
+#endif // FS_H
diff --git a/tools/atree/options.h b/tools/atree/options.h
new file mode 100644
index 0000000..a227d0f
--- /dev/null
+++ b/tools/atree/options.h
@@ -0,0 +1,14 @@
+#ifndef OPTIONS_H
+#define OPTIONS_H
+
+#include <string>
+#include <vector>
+
+using namespace std;
+
+extern vector<string> g_listFiles;
+extern vector<string> g_inputBases;
+extern string g_outputBase;
+extern bool g_useHardLinks;
+
+#endif // OPTIONS_H