diff --git a/updater/install.c b/updater/install.c
new file mode 100644
index 0000000..2336f61
--- /dev/null
+++ b/updater/install.c
@@ -0,0 +1,370 @@
+/*
+ * Copyright (C) 2009 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <stdio.h>
+#include <errno.h>
+#include <stdarg.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/mount.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#include "edify/expr.h"
+#include "minzip/DirUtil.h"
+#include "mtdutils/mounts.h"
+#include "mtdutils/mtdutils.h"
+#include "updater.h"
+
+char* ErrorAbort(void* cookie, char* format, ...) {
+    char* buffer = malloc(4096);
+    va_list v;
+    va_start(v, format);
+    vsnprintf(buffer, 4096, format, v);
+    va_end(v);
+    SetError(buffer);
+    return NULL;
+}
+
+// mount(type, location, mount_point)
+//
+//   what:  type="MTD"   location="<partition>"            to mount a yaffs2 filesystem
+//          type="vfat"  location="/dev/block/<whatever>"  to mount a device
+char* MountFn(const char* name, void* cookie, int argc, Expr* argv[]) {
+    char* result = NULL;
+    if (argc != 3) {
+        return ErrorAbort(cookie, "%s() expects 3 args, got %d", name, argc);
+    }
+    char* type;
+    char* location;
+    char* mount_point;
+    if (ReadArgs(cookie, argv, 3, &type, &location, &mount_point) < 0) {
+        return NULL;
+    }
+
+    if (strlen(type) == 0) {
+        ErrorAbort(cookie, "type argument to %s() can't be empty", name);
+        goto done;
+    }
+    if (strlen(location) == 0) {
+        ErrorAbort(cookie, "location argument to %s() can't be empty", name);
+        goto done;
+    }
+    if (strlen(mount_point) == 0) {
+        ErrorAbort(cookie, "mount_point argument to %s() can't be empty", name);
+        goto done;
+    }
+
+    mkdir(mount_point, 0755);
+
+    if (strcmp(type, "MTD") == 0) {
+        mtd_scan_partitions();
+        const MtdPartition* mtd;
+        mtd = mtd_find_partition_by_name(location);
+        if (mtd == NULL) {
+            fprintf(stderr, "%s: no mtd partition named \"%s\"",
+                    name, location);
+            result = strdup("");
+            goto done;
+        }
+        if (mtd_mount_partition(mtd, mount_point, "yaffs2", 0 /* rw */) != 0) {
+            fprintf(stderr, "mtd mount of %s failed: %s\n",
+                    location, strerror(errno));
+            result = strdup("");
+            goto done;
+        }
+        result = mount_point;
+    } else {
+        if (mount(location, mount_point, type,
+                  MS_NOATIME | MS_NODEV | MS_NODIRATIME, "") < 0) {
+            result = strdup("");
+        } else {
+            result = mount_point;
+        }
+    }
+
+done:
+    free(type);
+    free(location);
+    if (result != mount_point) free(mount_point);
+    return result;
+}
+
+char* UnmountFn(const char* name, void* cookie, int argc, Expr* argv[]) {
+    char* result = NULL;
+    if (argc != 1) {
+        return ErrorAbort(cookie, "%s() expects 1 arg, got %d", name, argc);
+    }
+    char* mount_point;
+    if (ReadArgs(cookie, argv, 1, &mount_point) < 0) {
+        return NULL;
+    }
+    if (strlen(mount_point) == 0) {
+        ErrorAbort(cookie, "mount_point argument to unmount() can't be empty");
+        goto done;
+    }
+
+    scan_mounted_volumes();
+    const MountedVolume* vol = find_mounted_volume_by_mount_point(mount_point);
+    if (vol == NULL) {
+        fprintf(stderr, "unmount of %s failed; no such volume\n", mount_point);
+        result = strdup("");
+    } else {
+        unmount_mounted_volume(vol);
+        result = mount_point;
+    }
+
+done:
+    if (result != mount_point) free(mount_point);
+    return result;
+}
+// format(type, location)
+//
+//    type="MTD"  location=partition
+char* FormatFn(const char* name, void* cookie, int argc, Expr* argv[]) {
+    char* result = NULL;
+    if (argc != 2) {
+        return ErrorAbort(cookie, "%s() expects 2 args, got %d", name, argc);
+    }
+    char* type;
+    char* location;
+    if (ReadArgs(cookie, argv, 2, &type, &location) < 0) {
+        return NULL;
+    }
+
+    if (strlen(type) == 0) {
+        ErrorAbort(cookie, "type argument to %s() can't be empty", name);
+        goto done;
+    }
+    if (strlen(location) == 0) {
+        ErrorAbort(cookie, "location argument to %s() can't be empty", name);
+        goto done;
+    }
+
+    if (strcmp(type, "MTD") == 0) {
+        mtd_scan_partitions();
+        const MtdPartition* mtd = mtd_find_partition_by_name(location);
+        if (mtd == NULL) {
+            fprintf(stderr, "%s: no mtd partition named \"%s\"",
+                    name, location);
+            result = strdup("");
+            goto done;
+        }
+        MtdWriteContext* ctx = mtd_write_partition(mtd);
+        if (ctx == NULL) {
+            fprintf(stderr, "%s: can't write \"%s\"", name, location);
+            result = strdup("");
+            goto done;
+        }
+        if (mtd_erase_blocks(ctx, -1) == -1) {
+            mtd_write_close(ctx);
+            fprintf(stderr, "%s: failed to erase \"%s\"", name, location);
+            result = strdup("");
+            goto done;
+        }
+        if (mtd_write_close(ctx) != 0) {
+            fprintf(stderr, "%s: failed to close \"%s\"", name, location);
+            result = strdup("");
+            goto done;
+        }
+        result = location;
+    } else {
+        fprintf(stderr, "%s: unsupported type \"%s\"", name, type);
+    }
+
+done:
+    free(type);
+    if (result != location) free(location);
+    return result;
+}
+
+char* DeleteFn(const char* name, void* cookie, int argc, Expr* argv[]) {
+    char** paths = malloc(argc * sizeof(char*));
+    int i;
+    for (i = 0; i < argc; ++i) {
+        paths[i] = Evaluate(cookie, argv[i]);
+        if (paths[i] == NULL) {
+            int j;
+            for (j = 0; j < i; ++i) {
+                free(paths[j]);
+            }
+            free(paths);
+            return NULL;
+        }
+    }
+
+    bool recursive = (strcmp(name, "delete_recursive") == 0);
+
+    int success = 0;
+    for (i = 0; i < argc; ++i) {
+        if ((recursive ? dirUnlinkHierarchy(paths[i]) : unlink(paths[i])) == 0)
+            ++success;
+        free(paths[i]);
+    }
+    free(paths);
+
+    char buffer[10];
+    sprintf(buffer, "%d", success);
+    return strdup(buffer);
+}
+
+char* ShowProgressFn(const char* name, void* cookie, int argc, Expr* argv[]) {
+    if (argc != 2) {
+        return ErrorAbort(cookie, "%s() expects 2 args, got %d", name, argc);
+    }
+    char* frac_str;
+    char* sec_str;
+    if (ReadArgs(cookie, argv, 2, &frac_str, &sec_str) < 0) {
+        return NULL;
+    }
+
+    double frac = strtod(frac_str, NULL);
+    int sec = strtol(sec_str, NULL, 10);
+
+    UpdaterInfo* ui = (UpdaterInfo*)cookie;
+    fprintf(ui->cmd_pipe, "progress %f %d\n", frac, sec);
+
+    free(frac_str);
+    free(sec_str);
+    return strdup("");
+}
+
+// package_extract package_path destination_path
+char* PackageExtractFn(const char* name, void* cookie, int argc, Expr* argv[]) {
+    if (argc != 2) {
+        return ErrorAbort(cookie, "%s() expects 2 args, got %d", name, argc);
+    }
+    char* zip_path;
+    char* dest_path;
+    if (ReadArgs(cookie, argv, 2, &zip_path, &dest_path) < 0) return NULL;
+
+    ZipArchive* za = ((UpdaterInfo*)cookie)->package_zip;
+
+    // To create a consistent system image, never use the clock for timestamps.
+    struct utimbuf timestamp = { 1217592000, 1217592000 };  // 8/1/2008 default
+
+    bool success = mzExtractRecursive(za, zip_path, dest_path,
+                                      MZ_EXTRACT_FILES_ONLY, &timestamp,
+                                      NULL, NULL);
+    free(zip_path);
+    free(dest_path);
+    return strdup(success ? "t" : "");
+}
+
+// symlink target src1 src2 ...
+char* SymlinkFn(const char* name, void* cookie, int argc, Expr* argv[]) {
+    if (argc == 0) {
+        return ErrorAbort(cookie, "%s() expects 1+ args, got %d", name, argc);
+    }
+    char* target;
+    target = Evaluate(cookie, argv[0]);
+    if (target == NULL) return NULL;
+
+    char** srcs = ReadVarArgs(cookie, argc-1, argv+1);
+    if (srcs == NULL) {
+        free(target);
+        return NULL;
+    }
+
+    int i;
+    for (i = 0; i < argc-1; ++i) {
+        symlink(target, srcs[i]);
+        free(srcs[i]);
+    }
+    free(srcs);
+    return strdup("");
+}
+
+char* SetPermFn(const char* name, void* cookie, int argc, Expr* argv[]) {
+    char* result = NULL;
+    bool recursive = (strcmp(name, "set_perm_recursive") == 0);
+
+    int min_args = 4 + (recursive ? 1 : 0);
+    if (argc < min_args) {
+        return ErrorAbort(cookie, "%s() expects %d+ args, got %d", name, argc);
+    }
+
+    char** args = ReadVarArgs(cookie, argc, argv);
+    if (args == NULL) return NULL;
+
+    char* end;
+    int i;
+
+    int uid = strtoul(args[0], &end, 0);
+    if (*end != '\0' || args[0][0] == 0) {
+        ErrorAbort(cookie, "%s: \"%s\" not a valid uid", name, args[0]);
+        goto done;
+    }
+
+    int gid = strtoul(args[1], &end, 0);
+    if (*end != '\0' || args[1][0] == 0) {
+        ErrorAbort(cookie, "%s: \"%s\" not a valid gid", name, args[1]);
+        goto done;
+    }
+
+    if (recursive) {
+        int dir_mode = strtoul(args[2], &end, 0);
+        if (*end != '\0' || args[2][0] == 0) {
+            ErrorAbort(cookie, "%s: \"%s\" not a valid dirmode", name, args[2]);
+            goto done;
+        }
+
+        int file_mode = strtoul(args[3], &end, 0);
+        if (*end != '\0' || args[3][0] == 0) {
+            ErrorAbort(cookie, "%s: \"%s\" not a valid filemode",
+                       name, args[3]);
+            goto done;
+        }
+
+        for (i = 4; i < argc; ++i) {
+            dirSetHierarchyPermissions(args[i], uid, gid, dir_mode, file_mode);
+        }
+    } else {
+        int mode = strtoul(args[2], &end, 0);
+        if (*end != '\0' || args[2][0] == 0) {
+            ErrorAbort(cookie, "%s: \"%s\" not a valid mode", name, args[2]);
+            goto done;
+        }
+
+        for (i = 4; i < argc; ++i) {
+            chown(args[i], uid, gid);
+            chmod(args[i], mode);
+        }
+    }
+    result = strdup("");
+
+done:
+    for (i = 0; i < argc; ++i) {
+        free(args[i]);
+    }
+    free(args);
+
+    return result;
+}
+
+void RegisterInstallFunctions() {
+    RegisterFunction("mount", MountFn);
+    RegisterFunction("unmount", UnmountFn);
+    RegisterFunction("format", FormatFn);
+    RegisterFunction("show_progress", ShowProgressFn);
+    RegisterFunction("delete", DeleteFn);
+    RegisterFunction("delete_recursive", DeleteFn);
+    RegisterFunction("package_extract", PackageExtractFn);
+    RegisterFunction("symlink", SymlinkFn);
+    RegisterFunction("set_perm", SetPermFn);
+    RegisterFunction("set_perm_recursive", SetPermFn);
+}